2 Bundle of old SSLeay documentation files [OBSOLETE!]
4 *** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! ***
6 OBSOLETE means that nothing in this document should be trusted. This
7 document is provided mostly for historical purposes (it wasn't even up
8 to date at the time SSLeay 0.8.1 was released) and as inspiration. If
9 you copy some snippet of code from this document, please _check_ that
10 it really is correct from all points of view. For example, you can
11 check with the other documents in this directory tree, or by comparing
12 with relevant parts of the include files.
14 People have done the mistake of trusting what's written here. Please
17 *** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! ***
20 ==== readme ========================================================
22 This is the old 0.6.6 docuementation. Most of the cipher stuff is still
23 relevent but I'm working (very slowly) on new documentation.
24 The current version can be found online at
26 http://www.cryptsoft.com/ssleay/doc
28 ==== API.doc ========================================================
30 SSL - SSLv2/v3/v23 etc.
32 BIO - methods and how they plug together
34 MEM - memory allocation callback
36 CRYPTO - locking for threads
38 EVP - Ciphers/Digests/signatures
42 X509 - certificate retrieval
46 X509 - X509v3 extensions
48 Objects - adding object identifiers
54 ==== ssl/readme =====================================================
57 This file belongs in ../apps, but I'll leave it here because it deals
58 with SSL :-) It is rather dated but it gives you an idea of how
63 I have been changing things quite a bit and have not fully updated
64 this file, so take what you read with a grain of salt
67 The s_client and s_server programs can be used to test SSL capable
68 IP/port addresses and the verification of the X509 certificates in use
69 by these services. I strongly advise having a look at the code to get
70 an idea of how to use the authentication under SSLeay. Any feedback
71 on changes and improvements would be greatly accepted.
73 This file will probably be gibberish unless you have read
74 rfc1421, rfc1422, rfc1423 and rfc1424 which describe PEM
77 A Brief outline (and examples) how to use them to do so.
80 The environment variable SSL_CIPER is used to specify the prefered
81 cipher to use, play around with setting it's value to combinations of
82 RC4-MD5, EXP-RC4-MD5, CBC-DES-MD5, CBC3-DES-MD5, CFB-DES-NULL
83 in a : separated list.
85 This directory contains 3 X509 certificates which can be used by these programs.
86 client.pem: a file containing a certificate and private key to be used
88 server.pem :a file containing a certificate and private key to be used
90 eay1024.pem:the certificate used to sign client.pem and server.pem.
91 This would be your CA's certificate. There is also a link
92 from the file a8556381.0 to eay1024.PEM. The value a8556381
93 is returned by 'x509 -hash -noout <eay1024.pem' and is the
94 value used by X509 verification routines to 'find' this
95 certificte when search a directory for it.
96 [the above is not true any more, the CA cert is
97 ../certs/testca.pem which is signed by ../certs/mincomca.pem]
99 When testing the s_server, you may get
100 bind: Address already in use
101 errors. These indicate the port is still being held by the unix
102 kernel and you are going to have to wait for it to let go of it. If
103 this is the case, remember to use the port commands on the s_server and
104 s_client to talk on an alternative port.
108 This program can be used to connect to any IP/hostname:port that is
109 talking SSL. Once connected, it will attempt to authenticate the
110 certificate it was passed and if everything works as expected, a 2
111 directional channel will be open. Any text typed will be sent to the
112 other end. type Q<cr> to exit. Flags are as follows.
113 -host arg : Arg is the host or IP address to connect to.
114 -port arg : Arg is the port to connect to (https is 443).
115 -verify arg : Turn on authentication of the server certificate.
116 : Arg specifies the 'depth', this will covered below.
117 -cert arg : The optional certificate to use. This certificate
118 : will be returned to the server if the server
119 : requests it for client authentication.
120 -key arg : The private key that matches the certificate
121 : specified by the -cert option. If this is not
122 : specified (but -cert is), the -cert file will be
123 : searched for the Private key. Both files are
124 : assumed to be in PEM format.
125 -CApath arg : When to look for certificates when 'verifying' the
126 : certificate from the server.
127 -CAfile arg : A file containing certificates to be used for
128 : 'verifying' the server certificate.
129 -reconnect : Once a connection has been made, drop it and
130 : reconnect with same session-id. This is for testing :-).
132 The '-verify n' parameter specifies not only to verify the servers
133 certificate but to also only take notice of 'n' levels. The best way
134 to explain is to show via examples.
136 s_server -cert server.PEM is running.
140 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
141 issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
142 verify error:num=1:unable to get issuer certificate
144 CIPHER is CBC-DES-MD5
145 What has happened is that the 'SSLeay demo server' certificate's
146 issuer ('CA') could not be found but because verify is not on, we
147 don't care and the connection has been made anyway. It is now 'up'
148 using CBC-DES-MD5 mode. This is an unauthenticate secure channel.
149 You may not be talking to the right person but the data going to them
154 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
155 issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
156 verify error:num=1:unable to get issuer certificate
158 CIPHER is CBC-DES-MD5
159 We are 'verifying' but only to depth 0, so since the 'SSLeay demo server'
160 certificate passed the date and checksum, we are happy to proceed.
164 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
165 issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
166 verify error:num=1:unable to get issuer certificate
169 verify error:unable to get issuer certificate
170 In this case we failed to make the connection because we could not
171 authenticate the certificate because we could not find the
174 s_client -verify 1 -CAfile eay1024.PEM
176 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
178 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
180 CIPHER is CBC-DES-MD5
181 We loaded the certificates from the file eay1024.PEM. Everything
182 checked out and so we made the connection.
184 s_client -verify 1 -CApath .
186 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
188 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
190 CIPHER is CBC-DES-MD5
191 We looked in out local directory for issuer certificates and 'found'
192 a8556381.0 and so everything is ok.
194 It is worth noting that 'CA' is a self certified certificate. If you
195 are passed one of these, it will fail to 'verify' at depth 0 because
196 we need to lookup the certifier of a certificate from some information
197 that we trust and keep locally.
199 SSL_CIPHER=CBC3-DES-MD5:RC4-MD5
201 s_client -verify 10 -CApath . -reconnect
203 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
205 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
207 drop the connection and reconnect with the same session id
208 CIPHER is CBC3-DES-MD5
209 This has done a full connection and then re-estabished it with the
210 same session id but a new socket. No RSA stuff occures on the second
211 connection. Note that we said we would prefer to use CBC3-DES-MD5
212 encryption and so, since the server supports it, we are.
216 This program accepts SSL connections on a specified port
217 Once connected, it will estabish an SSL connection and optionaly
218 attempt to authenticate the client. A 2 directional channel will be
219 open. Any text typed will be sent to the other end. Type Q<cr> to exit.
220 Flags are as follows.
221 -port arg : Arg is the port to listen on.
222 -verify arg : Turn on authentication of the client if they have a
223 : certificate. Arg specifies the 'depth'.
224 -Verify arg : Turn on authentication of the client. If they don't
225 : have a valid certificate, drop the connection.
226 -cert arg : The certificate to use. This certificate
227 : will be passed to the client. If it is not
228 : specified, it will default to server.PEM
229 -key arg : The private key that matches the certificate
230 : specified by the -cert option. If this is not
231 : specified (but -cert is), the -cert file will be
232 : searched for the Private key. Both files are
233 : assumed to be in PEM format. Default is server.PEM
234 -CApath arg : When to look for certificates when 'verifying' the
235 : certificate from the client.
236 -CAfile arg : A file containing certificates to be used for
237 : 'verifying' the client certificate.
239 For the following 'demo' I will specify the s_server command and
240 the s_client command and then list the output from the s_server.
244 CIPHER is CBC-DES-MD5
245 Everything up and running
250 CIPHER is CBC-DES-MD5
251 Ok since no certificate was returned and we don't care.
254 ./s_client -cert client.PEM
256 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
257 issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
258 verify error:num=1:unable to get issuer certificate
260 CIPHER is CBC-DES-MD5
261 Ok since we were only verifying to level 0
264 s_client -cert client.PEM
266 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
267 issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
268 verify error:num=1:unable to get issuer certificate
271 verify error:unable to get issuer certificate
272 Bad because we could not authenticate the returned certificate.
274 s_server -verify 4 -CApath .
275 s_client -cert client.PEM
277 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
279 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
281 CIPHER is CBC-DES-MD5
282 Ok because we could authenticate the returned certificate :-).
284 s_server -Verify 0 -CApath .
288 SSL error:function is:REQUEST_CERTIFICATE
289 :error is :client end did not return a certificate
290 Error because no certificate returned.
292 s_server -Verify 4 -CApath .
293 s_client -cert client.PEM
295 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
297 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
299 CIPHER is CBC-DES-MD5
300 Full authentication of the client.
302 So in summary to do full authentication of both ends
303 s_server -Verify 9 -CApath .
304 s_client -cert client.PEM -CApath . -verify 9
307 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
309 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
311 CIPHER is CBC-DES-MD5
314 depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
316 depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
318 CIPHER is CBC-DES-MD5
320 For general probing of the 'internet https' servers for the
321 distribution area, run
322 s_client -host www.netscape.com -port 443 -verify 4 -CApath ../rsa/hash
325 and you should be talking to the https server on that host.
327 www.rsa.com was refusing to respond to connections on 443 when I was
334 ==== a_verify.doc ========================================================
336 From eay@mincom.com Fri Oct 4 18:29:06 1996
337 Received: by orb.mincom.oz.au id AA29080
338 (5.65c/IDA-1.4.4 for eay); Fri, 4 Oct 1996 08:29:07 +1000
339 Date: Fri, 4 Oct 1996 08:29:06 +1000 (EST)
340 From: Eric Young <eay@mincom.oz.au>
342 To: wplatzer <wplatzer@iaik.tu-graz.ac.at>
343 Cc: Eric Young <eay@mincom.oz.au>, SSL Mailing List <ssl-users@mincom.com>
344 Subject: Re: Netscape's Public Key
345 In-Reply-To: <19961003134837.NTM0049@iaik.tu-graz.ac.at>
346 Message-Id: <Pine.SOL.3.91.961004081346.8018K-100000@orb>
348 Content-Type: TEXT/PLAIN; charset=US-ASCII
352 On Thu, 3 Oct 1996, wplatzer wrote:
353 > I get Public Key from Netscape (Gold 3.0b4), but cannot do anything
354 > with it... It looks like (asn1parse):
356 > 0:d=0 hl=3 l=180 cons: SEQUENCE
357 > 3:d=1 hl=2 l= 96 cons: SEQUENCE
358 > 5:d=2 hl=2 l= 92 cons: SEQUENCE
359 > 7:d=3 hl=2 l= 13 cons: SEQUENCE
360 > 9:d=4 hl=2 l= 9 prim: OBJECT :rsaEncryption
361 > 20:d=4 hl=2 l= 0 prim: NULL
362 > 22:d=3 hl=2 l= 75 prim: BIT STRING
363 > 99:d=2 hl=2 l= 0 prim: IA5STRING :
364 > 101:d=1 hl=2 l= 13 cons: SEQUENCE
365 > 103:d=2 hl=2 l= 9 prim: OBJECT :md5withRSAEncryption
366 > 114:d=2 hl=2 l= 0 prim: NULL
367 > 116:d=1 hl=2 l= 65 prim: BIT STRING
369 > The first BIT STRING is the public key and the second BIT STRING is
371 > But a public key consists of the public exponent and the modulus. Are
372 > both numbers in the first BIT STRING?
373 > Is there a document simply describing this coding stuff (checking
374 > signature, get the public key, etc.)?
376 Minimal in SSLeay. If you want to see what the modulus and exponent are,
377 try asn1parse -offset 25 -length 75 <key.pem
378 asn1parse will currently stuff up on the 'length 75' part (fixed in next
379 release) but it will print the stuff. If you are after more
380 documentation on ASN.1, have a look at www.rsa.com and get their PKCS
381 documents, most of my initial work on SSLeay was done using them.
384 util/crypto.num and util/ssl.num are lists of all exported functions in
385 the library (but not macros :-(.
387 The ones for extracting public keys from certificates and certificate
388 requests are EVP_PKEY * X509_REQ_extract_key(X509_REQ *req);
389 EVP_PKEY * X509_extract_key(X509 *x509);
391 To verify a signature on a signed ASN.1 object
392 int X509_verify(X509 *a,EVP_PKEY *key);
393 int X509_REQ_verify(X509_REQ *a,EVP_PKEY *key);
394 int X509_CRL_verify(X509_CRL *a,EVP_PKEY *key);
395 int NETSCAPE_SPKI_verify(NETSCAPE_SPKI *a,EVP_PKEY *key);
397 I should mention that EVP_PKEY can be used to hold a public or a private key,
398 since for things like RSA and DSS, a public key is just a subset of what
399 is stored for the private key.
401 To sign any of the above structures
403 int X509_sign(X509 *a,EVP_PKEY *key,EVP_MD *md);
404 int X509_REQ_sign(X509_REQ *a,EVP_PKEY *key,EVP_MD *md);
405 int X509_CRL_sign(X509_CRL *a,EVP_PKEY *key,EVP_MD *md);
406 int NETSCAPE_SPKI_sign(NETSCAPE_SPKI *a,EVP_PKEY *key,EVP_MD *md);
408 where md is the message digest to sign with.
410 There are all defined in x509.h and all the _sign and _verify functions are
411 actually macros to the ASN1_sign() and ASN1_verify() functions.
412 These functions will put the correct algorithm identifiers in the correct
413 places in the structures.
417 Eric Young | BOOL is tri-state according to Bill Gates.
418 AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage().
420 ==== x509 =======================================================
426 X509_get_serialNumber()
434 X509_set_serialNumber()
441 X509_get_extensions()
442 X509_set_extensions()
444 X509_EXTENSIONS_clear()
445 X509_EXTENSIONS_retrieve()
446 X509_EXTENSIONS_add()
447 X509_EXTENSIONS_delete()
449 ==== x509 attribute ================================================
452 STACK of X509_ATTRIBUTES
461 get_obj_by_nid(STACK , nid)
462 get_num_by_nid(STACK , nid)
463 get_data_by_nid(STACK , nid, index)
465 X509_ATTRIBUTE *X509_ATTRIBUTE_new(void );
466 void X509_ATTRIBUTE_free(X509_ATTRIBUTE *a);
468 X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_NID(X509_ATTRIBUTE **ex,
469 int nid, STACK *value);
471 X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_OBJ(X509_ATTRIBUTE **ex,
472 int nid, STACK *value);
474 int X509_ATTRIBUTE_set_object(X509_ATTRIBUTE *ex,ASN1_OBJECT *obj);
475 int X509_ATTRIBUTE_add_data(X509_ATTRIBUTE *ex, int index,
478 ASN1_OBJECT * X509_ATTRIBUTE_get_object(X509_ATTRIBUTE *ex);
479 int X509_ATTRIBUTE_get_num(X509_ATTRIBUTE *ne);
480 ASN1_TYPE * X509_ATTRIBUTE_get_data(X509_ATTRIBUTE *ne,int index);
482 ASN1_TYPE * X509_ATTRIBUTE_get_data_by_NID(X509_ATTRIBUTE *ne,
485 X509_ATTRIBUTE *PKCS7_get_s_att_by_NID(PKCS7 *p7,int nid);
486 X509_ATTRIBUTE *PKCS7_get_u_att_by_NID(PKCS7 *p7,int nid);
488 ==== x509 v3 ========================================================
492 The X509_EXTENSION_METHOD includes extensions and attributes and/or names.
493 Basically everthing that can be added to an X509 with an OID identifying it.
495 It operates via 2 methods per object id.
496 int a2i_XXX(X509 *x,char *str,int len);
497 int i2a_XXX(BIO *bp,X509 *x);
499 The a2i_XXX function will add the object with a value converted from the
500 string into the X509. Len can be -1 in which case the length is calculated
501 via strlen(str). Applications can always use direct knowledge to load and
502 unload the relevent objects themselves.
504 i2a_XXX will print to the passed BIO, a text representation of the
505 relevet object. Use a memory BIO if you want it printed to a buffer :-).
507 X509_add_by_NID(X509 *x,int nid,char *str,int len);
508 X509_add_by_OBJ(X509 *x,ASN1_OBJECT *obj,char *str,int len);
510 X509_print_by_name(BIO *bp,X509 *x);
511 X509_print_by_NID(BIO *bp,X509 *x);
512 X509_print_by_OBJ(BIO *bp,X509 *x);
514 ==== verify ========================================================
516 X509_verify_cert_chain(
517 CERT_STORE *cert_store,
518 STACK /* X509 */ *certs,
520 int (*verify_error_callback)()
521 char *argument_to_callback, /* SSL */
524 char *app_verify_arg, /* from SSL_CTX */
525 STACK /* X509 */ *certs,
527 int (*verify_error_callback)()
530 int X509_verify_cert(
531 CERT_STORE *cert_store,
534 int (*verify_error_callback)(),
537 ==== apps.doc ========================================================
541 Ok, where to begin....
542 In the begining, when SSLeay was small (April 1995), there
543 were but few applications, they did happily cohabit in
544 the one bin directory. Then over time, they did multiply and grow,
545 and they started to look like microsoft software; 500k to print 'hello world'.
546 A new approach was needed. They were coalessed into one 'Monolithic'
547 application, ssleay. This one program is composed of many programs that
548 can all be compiled independantly.
550 ssleay has 3 modes of operation.
551 1) If the ssleay binary has the name of one of its component programs, it
552 executes that program and then exits. This can be achieved by using hard or
553 symbolic links, or failing that, just renaming the binary.
554 2) If the first argument to ssleay is the name of one of the component
555 programs, that program runs that program and then exits.
556 3) If there are no arguments, ssleay enters a 'command' mode. Each line is
557 interpreted as a program name plus arguments. After each 'program' is run,
558 ssleay returns to the comand line.
560 dgst - message digests
561 enc - encryption and base64 encoding
563 ans1parse - 'pulls' appart ASN.1 encoded objects like certificates.
565 dh - Diffle-Hellman parameter manipulation.
566 rsa - RSA manipulations.
567 crl - Certificate revokion list manipulations
568 x509 - X509 cert fiddles, including signing.
569 pkcs7 - pkcs7 manipulation, only DER versions right now.
571 genrsa - generate an RSA private key.
572 gendh - Generate a set of Diffle-Hellman parameters.
573 req - Generate a PKCS#10 object, a certificate request.
575 s_client - SSL client program
576 s_server - SSL server program
577 s_time - A SSL protocol timing program
578 s_mult - Another SSL server, but it multiplexes
580 s_filter - under development
582 errstr - Convert SSLeay error numbers to strings.
583 ca - Sign certificate requests, and generate
584 certificate revokion lists
585 crl2pkcs7 - put a crl and certifcates into a pkcs7 object.
586 speed - Benchmark the ciphers.
587 verify - Check certificates
588 hashdir - under development
590 [ there a now a few more options, play with the program to see what they
593 ==== asn1.doc ========================================================
597 ASN.1 is a specification for how to encode structured 'data' in binary form.
598 The approach I have take to the manipulation of structures and their encoding
599 into ASN.1 is as follows.
601 For each distinct structure there are 4 function of the following form
602 TYPE *TYPE_new(void);
603 void TYPE_free(TYPE *);
604 TYPE *d2i_TYPE(TYPE **a,unsigned char **pp,long length);
605 long i2d_TYPE(TYPE *a,unsigned char **pp); /* CHECK RETURN VALUE */
607 where TYPE is the type of the 'object'. The TYPE that have these functions
608 can be in one of 2 forms, either the internal C malloc()ed data structure
609 or in the DER (a variant of ASN.1 encoding) binary encoding which is just
610 an array of unsigned bytes. The 'i2d' functions converts from the internal
611 form to the DER form and the 'd2i' functions convert from the DER form to
614 The 'new' function returns a malloc()ed version of the structure with all
615 substructures either created or left as NULL pointers. For 'optional'
616 fields, they are normally left as NULL to indicate no value. For variable
617 size sub structures (often 'SET OF' or 'SEQUENCE OF' in ASN.1 syntax) the
618 STACK data type is used to hold the values. Have a read of stack.doc
619 and have a look at the relevant header files to see what I mean. If there
620 is an error while malloc()ing the structure, NULL is returned.
622 The 'free' function will free() all the sub components of a particular
623 structure. If any of those sub components have been 'removed', replace
624 them with NULL pointers, the 'free' functions are tolerant of NULL fields.
626 The 'd2i' function copies a binary representation into a C structure. It
627 operates as follows. 'a' is a pointer to a pointer to
628 the structure to populate, 'pp' is a pointer to a pointer to where the DER
629 byte string is located and 'length' is the length of the '*pp' data.
630 If there are no errors, a pointer to the populated structure is returned.
631 If there is an error, NULL is returned. Errors can occur because of
632 malloc() failures but normally they will be due to syntax errors in the DER
633 encoded data being parsed. It is also an error if there was an
634 attempt to read more that 'length' bytes from '*p'. If
635 everything works correctly, the value in '*p' is updated
636 to point at the location just beyond where the DER
637 structure was read from. In this way, chained calls to 'd2i' type
638 functions can be made, with the pointer into the 'data' array being
639 'walked' along the input byte array.
640 Depending on the value passed for 'a', different things will be done. If
641 'a' is NULL, a new structure will be malloc()ed and returned. If '*a' is
642 NULL, a new structure will be malloc()ed and put into '*a' and returned.
643 If '*a' is not NULL, the structure in '*a' will be populated, or in the
644 case of an error, free()ed and then returned.
645 Having these semantics means that a structure
646 can call a 'd2i' function to populate a field and if the field is currently
647 NULL, the structure will be created.
649 The 'i2d' function type is used to copy a C structure to a byte array.
650 The parameter 'a' is the structure to convert and '*p' is where to put it.
651 As for the 'd2i' type structure, 'p' is updated to point after the last
652 byte written. If p is NULL, no data is written. The function also returns
653 the number of bytes written. Where this becomes useful is that if the
654 function is called with a NULL 'p' value, the length is returned. This can
655 then be used to malloc() an array of bytes and then the same function can
656 be recalled passing the malloced array to be written to. e.g.
659 unsigned char *bytes,*p;
660 len=i2d_X509(x,NULL); /* get the size of the ASN1 encoding of 'x' */
661 if ((bytes=(unsigned char *)malloc(len)) == NULL)
666 Please note that a new variable, 'p' was passed to i2d_X509. After the
667 call to i2d_X509 p has been incremented by len bytes.
669 Now the reason for this functional organisation is that it allows nested
670 structures to be built up by calling these functions as required. There
671 are various macros used to help write the general 'i2d', 'd2i', 'new' and
672 'free' functions. They are discussed in another file and would only be
673 used by some-one wanting to add new structures to the library. As you
674 might be able to guess, the process of writing ASN.1 files can be a bit CPU
675 expensive for complex structures. I'm willing to live with this since the
676 simpler library code make my life easier and hopefully most programs using
677 these routines will have their execution profiles dominated by cipher or
678 message digest routines.
679 What follows is a list of 'TYPE' values and the corresponding ASN.1
680 structure and where it is used.
684 ASN1_BIT_STRING BIT STRING
685 ASN1_OCTET_STRING OCTET STRING
686 ASN1_OBJECT OBJECT IDENTIFIER
687 ASN1_PRINTABLESTRING PrintableString
688 ASN1_T61STRING T61String
689 ASN1_IA5STRING IA5String
691 ASN1_TYPE Any of the above mentioned types plus SEQUENCE and SET
693 Most of the above mentioned types are actualled stored in the
694 ASN1_BIT_STRING type and macros are used to differentiate between them.
697 typedef struct asn1_object_st
699 /* both null if a dynamic ASN1_OBJECT, one is
700 * defined if a 'static' ASN1_OBJECT */
706 This is used to store ASN1 OBJECTS. Read 'objects.doc' for details ono
707 routines to manipulate this structure. 'sn' and 'ln' are used to hold text
708 strings that represent the object (short name and long or lower case name).
709 These are used by the 'OBJ' library. 'nid' is a number used by the OBJ
710 library to uniquely identify objects. The ASN1 routines will populate the
711 'length' and 'data' fields which will contain the bit string representing
714 typedef struct asn1_bit_string_st
720 This structure is used to hold all the other base ASN1 types except for
721 ASN1_UTCTIME (which is really just a 'char *'). Length is the number of
722 bytes held in data and type is the ASN1 type of the object (there is a list
725 typedef struct asn1_type_st
730 ASN1_INTEGER * integer;
731 ASN1_BIT_STRING * bit_string;
732 ASN1_OCTET_STRING * octet_string;
733 ASN1_OBJECT * object;
734 ASN1_PRINTABLESTRING * printablestring;
735 ASN1_T61STRING * t61string;
736 ASN1_IA5STRING * ia5string;
737 ASN1_UTCTIME * utctime;
738 ASN1_BIT_STRING * set;
739 ASN1_BIT_STRING * sequence;
742 This structure is used in a few places when 'any' type of object can be
746 X509_CINF CertificateInfo
747 X509_ALGOR AlgorithmIdentifier
749 X509_NAME_ENTRY A single sub component of the name.
751 X509_PUBKEY SubjectPublicKeyInfo
752 The above mentioned types are declared in x509.h. They are all quite
753 straight forward except for the X509_NAME/X509_NAME_ENTRY pair.
754 A X509_NAME is a STACK (see stack.doc) of X509_NAME_ENTRY's.
755 typedef struct X509_name_entry_st
758 ASN1_BIT_STRING *value;
760 int size; /* temp variable */
762 The size is a temporary variable used by i2d_NAME and set is the set number
763 for the particular NAME_ENTRY. A X509_NAME is encoded as a sequence of
764 sequence of sets. Normally each set contains only a single item.
765 Sometimes it contains more. Normally throughout this library there will be
766 only one item per set. The set field contains the 'set' that this entry is
767 a member of. So if you have just created a X509_NAME structure and
768 populated it with X509_NAME_ENTRYs, you should then traverse the X509_NAME
769 (which is just a STACK) and set the 'set/' field to incrementing numbers.
770 For more details on why this is done, read the ASN.1 spec for Distinguished
773 X509_REQ CertificateRequest
774 X509_REQ_INFO CertificateRequestInfo
775 These are used to hold certificate requests.
777 X509_CRL CertificateRevocationList
778 These are used to hold a certificate revocation list
780 RSAPrivateKey PrivateKeyInfo
781 RSAPublicKey PublicKeyInfo
782 Both these 'function groups' operate on 'RSA' structures (see rsa.doc).
783 The difference is that the RSAPublicKey operations only manipulate the m
784 and e fields in the RSA structure.
786 DSAPrivateKey DSS private key
787 DSAPublicKey DSS public key
788 Both these 'function groups' operate on 'DSS' structures (see dsa.doc).
789 The difference is that the RSAPublicKey operations only manipulate the
790 XXX fields in the DSA structure.
793 This is used to hold the p and g value for The Diffie-Hellman operation.
794 The function deal with the 'DH' strucure (see dh.doc).
796 Now all of these function types can be used with several other functions to give
797 quite useful set of general manipulation routines. Normally one would
798 not uses these functions directly but use them via macros.
800 char *ASN1_dup(int (*i2d)(),char *(*d2i)(),char *x);
801 'x' is the input structure case to a 'char *', 'i2d' is the 'i2d_TYPE'
802 function for the type that 'x' is and d2i is the 'd2i_TYPE' function for the
803 type that 'x' is. As is obvious from the parameters, this function
804 duplicates the strucutre by transforming it into the DER form and then
805 re-loading it into a new strucutre and returning the new strucutre. This
806 is obviously a bit cpu intensive but when faced with a complex dynamic
807 structure this is the simplest programming approach. There are macros for
808 duplicating the major data types but is simple to add extras.
810 char *ASN1_d2i_fp(char *(*new)(),char *(*d2i)(),FILE *fp,unsigned char **x);
811 'x' is a pointer to a pointer of the 'desired type'. new and d2i are the
812 corresponding 'TYPE_new' and 'd2i_TYPE' functions for the type and 'fp' is
813 an open file pointer to read from. This function reads from 'fp' as much
814 data as it can and then uses 'd2i' to parse the bytes to load and return
815 the parsed strucutre in 'x' (if it was non-NULL) and to actually return the
816 strucutre. The behavior of 'x' is as per all the other d2i functions.
818 char *ASN1_d2i_bio(char *(*new)(),char *(*d2i)(),BIO *fp,unsigned char **x);
819 The 'BIO' is the new IO type being used in SSLeay (see bio.doc). This
820 function is the same as ASN1_d2i_fp() except for the BIO argument.
821 ASN1_d2i_fp() actually calls this function.
823 int ASN1_i2d_fp(int (*i2d)(),FILE *out,unsigned char *x);
824 'x' is converted to bytes by 'i2d' and then written to 'out'. ASN1_i2d_fp
825 and ASN1_d2i_fp are not really symetric since ASN1_i2d_fp will read all
826 available data from the file pointer before parsing a single item while
827 ASN1_i2d_fp can be used to write a sequence of data objects. To read a
828 series of objects from a file I would sugest loading the file into a buffer
829 and calling the relevent 'd2i' functions.
831 char *ASN1_d2i_bio(char *(*new)(),char *(*d2i)(),BIO *fp,unsigned char **x);
832 This function is the same as ASN1_i2d_fp() except for the BIO argument.
833 ASN1_i2d_fp() actually calls this function.
835 char * PEM_ASN1_read(char *(*d2i)(),char *name,FILE *fp,char **x,int (*cb)());
836 This function will read the next PEM encoded (base64) object of the same
837 type as 'x' (loaded by the d2i function). 'name' is the name that is in
838 the '-----BEGIN name-----' that designates the start of that object type.
839 If the data is encrypted, 'cb' will be called to prompt for a password. If
840 it is NULL a default function will be used to prompt from the password.
841 'x' is delt with as per the standard 'd2i' function interface. This
842 function can be used to read a series of objects from a file. While any
843 data type can be encrypted (see PEM_ASN1_write) only RSA private keys tend
846 char * PEM_ASN1_read_bio(char *(*d2i)(),char *name,BIO *fp,
847 char **x,int (*cb)());
848 Same as PEM_ASN1_read() except using a BIO. This is called by
851 int PEM_ASN1_write(int (*i2d)(),char *name,FILE *fp,char *x,EVP_CIPHER *enc,
852 unsigned char *kstr,int klen,int (*callback)());
854 int PEM_ASN1_write_bio(int (*i2d)(),char *name,BIO *fp,
855 char *x,EVP_CIPHER *enc,unsigned char *kstr,int klen,
858 int ASN1_sign(int (*i2d)(), X509_ALGOR *algor1, X509_ALGOR *algor2,
859 ASN1_BIT_STRING *signature, char *data, RSA *rsa, EVP_MD *type);
860 int ASN1_verify(int (*i2d)(), X509_ALGOR *algor1,
861 ASN1_BIT_STRING *signature,char *data, RSA *rsa);
863 int ASN1_BIT_STRING_cmp(ASN1_BIT_STRING *a, ASN1_BIT_STRING *b);
864 ASN1_BIT_STRING *ASN1_BIT_STRING_type_new(int type );
866 int ASN1_UTCTIME_check(ASN1_UTCTIME *a);
867 void ASN1_UTCTIME_print(BIO *fp,ASN1_UTCTIME *a);
868 ASN1_UTCTIME *ASN1_UTCTIME_dup(ASN1_UTCTIME *a);
870 ASN1_BIT_STRING *d2i_asn1_print_type(ASN1_BIT_STRING **a,unsigned char **pp,
871 long length,int type);
873 int i2d_ASN1_SET(STACK *a, unsigned char **pp,
874 int (*func)(), int ex_tag, int ex_class);
875 STACK * d2i_ASN1_SET(STACK **a, unsigned char **pp, long length,
876 char *(*func)(), int ex_tag, int ex_class);
878 int i2a_ASN1_OBJECT(BIO *bp,ASN1_OBJECT *object);
879 int i2a_ASN1_INTEGER(BIO *bp, ASN1_INTEGER *a);
880 int a2i_ASN1_INTEGER(BIO *bp,ASN1_INTEGER *bs,char *buf,int size);
882 int ASN1_INTEGER_set(ASN1_INTEGER *a, long v);
883 long ASN1_INTEGER_get(ASN1_INTEGER *a);
884 ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai);
885 BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai,BIGNUM *bn);
887 /* given a string, return the correct type. Max is the maximum number
888 * of bytes to parse. It stops parsing when 'max' bytes have been
889 * processed or a '\0' is hit */
890 int ASN1_PRINTABLE_type(unsigned char *s,int max);
892 void ASN1_parse(BIO *fp,unsigned char *pp,long len);
894 int i2d_ASN1_bytes(ASN1_BIT_STRING *a, unsigned char **pp, int tag, int class);
895 ASN1_BIT_STRING *d2i_ASN1_bytes(ASN1_OCTET_STRING **a, unsigned char **pp,
896 long length, int Ptag, int Pclass);
899 int asn1_Finish(ASN1_CTX *c);
902 int ASN1_get_object(unsigned char **pp, long *plength, int *ptag,
903 int *pclass, long omax);
904 int ASN1_check_infinite_end(unsigned char **p,long len);
905 void ASN1_put_object(unsigned char **pp, int constructed, int length,
907 int ASN1_object_size(int constructed, int length, int tag);
909 X509 * X509_get_cert(CERTIFICATE_CTX *ctx,X509_NAME * name,X509 *tmp_x509);
910 int X509_add_cert(CERTIFICATE_CTX *ctx,X509 *);
912 char * X509_cert_verify_error_string(int n);
913 int X509_add_cert_file(CERTIFICATE_CTX *c,char *file, int type);
914 char * X509_gmtime (char *s, long adj);
915 int X509_add_cert_dir (CERTIFICATE_CTX *c,char *dir, int type);
916 int X509_load_verify_locations (CERTIFICATE_CTX *ctx,
917 char *file_env, char *dir_env);
918 int X509_set_default_verify_paths(CERTIFICATE_CTX *cts);
919 X509 * X509_new_D2i_X509(int len, unsigned char *p);
920 char * X509_get_default_cert_area(void );
921 char * X509_get_default_cert_dir(void );
922 char * X509_get_default_cert_file(void );
923 char * X509_get_default_cert_dir_env(void );
924 char * X509_get_default_cert_file_env(void );
925 char * X509_get_default_private_dir(void );
926 X509_REQ *X509_X509_TO_req(X509 *x, RSA *rsa);
927 int X509_cert_verify(CERTIFICATE_CTX *ctx,X509 *xs, int (*cb)());
929 CERTIFICATE_CTX *CERTIFICATE_CTX_new();
930 void CERTIFICATE_CTX_free(CERTIFICATE_CTX *c);
932 void X509_NAME_print(BIO *fp, X509_NAME *name, int obase);
933 int X509_print_fp(FILE *fp,X509 *x);
934 int X509_print(BIO *fp,X509 *x);
936 X509_INFO * X509_INFO_new(void);
937 void X509_INFO_free(X509_INFO *a);
939 char * X509_NAME_oneline(X509_NAME *a);
941 #define X509_verify(x,rsa)
942 #define X509_REQ_verify(x,rsa)
943 #define X509_CRL_verify(x,rsa)
945 #define X509_sign(x,rsa,md)
946 #define X509_REQ_sign(x,rsa,md)
947 #define X509_CRL_sign(x,rsa,md)
949 #define X509_dup(x509)
950 #define d2i_X509_fp(fp,x509)
951 #define i2d_X509_fp(fp,x509)
952 #define d2i_X509_bio(bp,x509)
953 #define i2d_X509_bio(bp,x509)
955 #define X509_CRL_dup(crl)
956 #define d2i_X509_CRL_fp(fp,crl)
957 #define i2d_X509_CRL_fp(fp,crl)
958 #define d2i_X509_CRL_bio(bp,crl)
959 #define i2d_X509_CRL_bio(bp,crl)
961 #define X509_REQ_dup(req)
962 #define d2i_X509_REQ_fp(fp,req)
963 #define i2d_X509_REQ_fp(fp,req)
964 #define d2i_X509_REQ_bio(bp,req)
965 #define i2d_X509_REQ_bio(bp,req)
967 #define RSAPrivateKey_dup(rsa)
968 #define d2i_RSAPrivateKey_fp(fp,rsa)
969 #define i2d_RSAPrivateKey_fp(fp,rsa)
970 #define d2i_RSAPrivateKey_bio(bp,rsa)
971 #define i2d_RSAPrivateKey_bio(bp,rsa)
973 #define X509_NAME_dup(xn)
974 #define X509_NAME_ENTRY_dup(ne)
976 void X509_REQ_print_fp(FILE *fp,X509_REQ *req);
977 void X509_REQ_print(BIO *fp,X509_REQ *req);
979 RSA *X509_REQ_extract_key(X509_REQ *req);
980 RSA *X509_extract_key(X509 *x509);
982 int X509_issuer_and_serial_cmp(X509 *a, X509 *b);
983 unsigned long X509_issuer_and_serial_hash(X509 *a);
985 X509_NAME * X509_get_issuer_name(X509 *a);
986 int X509_issuer_name_cmp(X509 *a, X509 *b);
987 unsigned long X509_issuer_name_hash(X509 *a);
989 X509_NAME * X509_get_subject_name(X509 *a);
990 int X509_subject_name_cmp(X509 *a,X509 *b);
991 unsigned long X509_subject_name_hash(X509 *x);
993 int X509_NAME_cmp (X509_NAME *a, X509_NAME *b);
994 unsigned long X509_NAME_hash(X509_NAME *x);
997 ==== bio.doc ========================================================
1001 This documentation is rather sparse, you are probably best
1002 off looking at the code for specific details.
1004 The BIO library is a IO abstraction that was originally
1005 inspired by the need to have callbacks to perform IO to FILE
1006 pointers when using Windows 3.1 DLLs. There are two types
1007 of BIO; a source/sink type and a filter type.
1008 The source/sink methods are as follows:
1009 - BIO_s_mem() memory buffer - a read/write byte array that
1010 grows until memory runs out :-).
1011 - BIO_s_file() FILE pointer - A wrapper around the normal
1012 'FILE *' commands, good for use with stdin/stdout.
1013 - BIO_s_fd() File descriptor - A wrapper around file
1014 descriptors, often used with pipes.
1015 - BIO_s_socket() Socket - Used around sockets. It is
1016 mostly in the Microsoft world that sockets are different
1017 from file descriptors and there are all those ugly winsock
1019 - BIO_s_null() Null - read nothing and write nothing.; a
1020 useful endpoint for filter type BIO's specifically things
1021 like the message digest BIO.
1023 The filter types are
1024 - BIO_f_buffer() IO buffering - does output buffering into
1025 larger chunks and performs input buffering to allow gets()
1027 - BIO_f_md() Message digest - a transparent filter that can
1028 be asked to return a message digest for the data that has
1030 - BIO_f_cipher() Encrypt or decrypt all data passing
1032 - BIO_f_base64() Base64 decode on read and encode on write.
1033 - BIO_f_ssl() A filter that performs SSL encryption on the
1034 data sent through it.
1037 The BIO library has a set of base functions that are
1038 implemented for each particular type. Filter BIOs will
1039 normally call the equivalent function on the source/sink BIO
1040 that they are layered on top of after they have performed
1041 some modification to the data stream. Multiple filter BIOs
1042 can be 'push' into a stack of modifers, so to read from a
1043 file, unbase64 it, then decrypt it, a BIO_f_cipher,
1044 BIO_f_base64 and a BIO_s_file would probably be used. If a
1045 sha-1 and md5 message digest needed to be generated, a stack
1046 two BIO_f_md() BIOs and a BIO_s_null() BIO could be used.
1047 The base functions are
1048 - BIO *BIO_new(BIO_METHOD *type); Create a new BIO of type 'type'.
1049 - int BIO_free(BIO *a); Free a BIO structure. Depending on
1050 the configuration, this will free the underlying data
1051 object for a source/sink BIO.
1052 - int BIO_read(BIO *b, char *data, int len); Read upto 'len'
1054 - int BIO_gets(BIO *bp,char *buf, int size); Depending on
1055 the BIO, this can either be a 'get special' or a get one
1056 line of data, as per fgets();
1057 - int BIO_write(BIO *b, char *data, int len); Write 'len'
1058 bytes from 'data' to the 'b' BIO.
1059 - int BIO_puts(BIO *bp,char *buf); Either a 'put special' or
1060 a write null terminated string as per fputs().
1061 - long BIO_ctrl(BIO *bp,int cmd,long larg,char *parg); A
1062 control function which is used to manipulate the BIO
1063 structure and modify it's state and or report on it. This
1064 function is just about never used directly, rather it
1065 should be used in conjunction with BIO_METHOD specific
1067 - BIO *BIO_push(BIO *new_top, BIO *old); new_top is apped to the
1068 top of the 'old' BIO list. new_top should be a filter BIO.
1069 All writes will go through 'new_top' first and last on read.
1071 - BIO *BIO_pop(BIO *bio); the new topmost BIO is returned, NULL if
1074 If a particular low level BIO method is not supported
1075 (normally BIO_gets()), -2 will be returned if that method is
1076 called. Otherwise the IO methods (read, write, gets, puts)
1077 will return the number of bytes read or written, and 0 or -1
1078 for error (or end of input). For the -1 case,
1079 BIO_should_retry(bio) can be called to determine if it was a
1080 genuine error or a temporary problem. -2 will also be
1081 returned if the BIO has not been initalised yet, in all
1082 cases, the correct error codes are set (accessible via the
1086 The following functions are convenience functions:
1087 - int BIO_printf(BIO *bio, char * format, ..); printf but
1089 - long BIO_ctrl_int(BIO *bp,int cmd,long larg,int iarg); a
1090 convenience function to allow a different argument types
1091 to be passed to BIO_ctrl().
1092 - int BIO_dump(BIO *b,char *bytes,int len); output 'len'
1093 bytes from 'bytes' in a hex dump debug format.
1094 - long BIO_debug_callback(BIO *bio, int cmd, char *argp, int
1095 argi, long argl, long ret) - a default debug BIO callback,
1096 this is mentioned below. To use this one normally has to
1097 use the BIO_set_callback_arg() function to assign an
1098 output BIO for the callback to use.
1099 - BIO *BIO_find_type(BIO *bio,int type); when there is a 'stack'
1100 of BIOs, this function scan the list and returns the first
1101 that is of type 'type', as listed in buffer.h under BIO_TYPE_XXX.
1102 - void BIO_free_all(BIO *bio); Free the bio and all other BIOs
1103 in the list. It walks the bio->next_bio list.
1107 Extra commands are normally implemented as macros calling BIO_ctrl().
1108 - BIO_number_read(BIO *bio) - the number of bytes processed
1110 - BIO_number_written(BIO *bio) - the number of bytes written
1111 by BIO_write(bio,.).
1112 - BIO_reset(BIO *bio) - 'reset' the BIO.
1113 - BIO_eof(BIO *bio) - non zero if we are at the current end
1115 - BIO_set_close(BIO *bio, int close_flag) - set the close flag.
1116 - BIO_get_close(BIO *bio) - return the close flag.
1117 BIO_pending(BIO *bio) - return the number of bytes waiting
1118 to be read (normally buffered internally).
1119 - BIO_flush(BIO *bio) - output any data waiting to be output.
1120 - BIO_should_retry(BIO *io) - after a BIO_read/BIO_write
1121 operation returns 0 or -1, a call to this function will
1122 return non zero if you should retry the call later (this
1123 is for non-blocking IO).
1124 - BIO_should_read(BIO *io) - we should retry when data can
1126 - BIO_should_write(BIO *io) - we should retry when data can
1128 - BIO_method_name(BIO *io) - return a string for the method name.
1129 - BIO_method_type(BIO *io) - return the unique ID of the BIO method.
1130 - BIO_set_callback(BIO *io, long (*callback)(BIO *io, int
1131 cmd, char *argp, int argi, long argl, long ret); - sets
1133 - BIO_get_callback(BIO *io) - return the assigned function
1135 - BIO_set_callback_arg(BIO *io, char *arg) - assign some
1136 data against the BIO. This is normally used by the debug
1137 callback but could in reality be used for anything. To
1138 get an idea of how all this works, have a look at the code
1139 in the default debug callback mentioned above. The
1140 callback can modify the return values.
1142 Details of the BIO_METHOD structure.
1143 typedef struct bio_method_st
1156 The 'type' is the numeric type of the BIO, these are listed in buffer.h;
1157 'Name' is a textual representation of the BIO 'type'.
1158 The 7 function pointers point to the respective function
1159 methods, some of which can be NULL if not implemented.
1161 typedef struct bio_st
1164 long (*callback)(BIO * bio, int mode, char *argp, int
1165 argi, long argl, long ret);
1166 char *cb_arg; /* first argument for the callback */
1169 int flags; /* extra storage */
1172 struct bio_st *next_bio; /* used by filter BIOs */
1174 unsigned long num_read;
1175 unsigned long num_write;
1178 - 'Method' is the BIO method.
1179 - 'callback', when configured, is called before and after
1180 each BIO method is called for that particular BIO. This
1181 is intended primarily for debugging and of informational feedback.
1182 - 'init' is 0 when the BIO can be used for operation.
1183 Often, after a BIO is created, a number of operations may
1184 need to be performed before it is available for use. An
1185 example is for BIO_s_sock(). A socket needs to be
1186 assigned to the BIO before it can be used.
1187 - 'shutdown', this flag indicates if the underlying
1188 communication primitive being used should be closed/freed
1189 when the BIO is closed.
1190 - 'flags' is used to hold extra state. It is primarily used
1191 to hold information about why a non-blocking operation
1192 failed and to record startup protocol information for the
1194 - 'num' and 'ptr' are used to hold instance specific state
1195 like file descriptors or local data structures.
1196 - 'next_bio' is used by filter BIOs to hold the pointer of the
1197 next BIO in the chain. written data is sent to this BIO and
1198 data read is taken from it.
1199 - 'references' is used to indicate the number of pointers to
1200 this structure. This needs to be '1' before a call to
1201 BIO_free() is made if the BIO_free() function is to
1202 actually free() the structure, otherwise the reference
1203 count is just decreased. The actual BIO subsystem does
1204 not really use this functionality but it is useful when
1205 used in more advanced applicaion.
1206 - num_read and num_write are the total number of bytes
1207 read/written via the 'read()' and 'write()' methods.
1209 BIO_ctrl operations.
1210 The following is the list of standard commands passed as the
1211 second parameter to BIO_ctrl() and should be supported by
1212 all BIO as best as possible. Some are optional, some are
1213 manditory, in any case, where is makes sense, a filter BIO
1214 should pass such requests to underlying BIO's.
1215 - BIO_CTRL_RESET - Reset the BIO back to an initial state.
1216 - BIO_CTRL_EOF - return 0 if we are not at the end of input,
1218 - BIO_CTRL_INFO - BIO specific special command, normal
1220 - BIO_CTRL_SET - set IO specific parameter.
1221 - BIO_CTRL_GET - get IO specific parameter.
1222 - BIO_CTRL_GET_CLOSE - Get the close on BIO_free() flag, one
1223 of BIO_CLOSE or BIO_NOCLOSE.
1224 - BIO_CTRL_SET_CLOSE - Set the close on BIO_free() flag.
1225 - BIO_CTRL_PENDING - Return the number of bytes available
1227 - BIO_CTRL_FLUSH - Output pending data, return number of bytes output.
1228 - BIO_CTRL_SHOULD_RETRY - After an IO error (-1 returned)
1229 should we 'retry' when IO is possible on the underlying IO object.
1230 - BIO_CTRL_RETRY_TYPE - What kind of IO are we waiting on.
1232 The following command is a special BIO_s_file() specific option.
1233 - BIO_CTRL_SET_FILENAME - specify a file to open for IO.
1235 The BIO_CTRL_RETRY_TYPE needs a little more explanation.
1236 When performing non-blocking IO, or say reading on a memory
1237 BIO, when no data is present (or cannot be written),
1238 BIO_read() and/or BIO_write() will return -1.
1239 BIO_should_retry(bio) will return true if this is due to an
1240 IO condition rather than an actual error. In the case of
1241 BIO_s_mem(), a read when there is no data will return -1 and
1242 a should retry when there is more 'read' data.
1243 The retry type is deduced from 2 macros
1244 BIO_should_read(bio) and BIO_should_write(bio).
1245 Now while it may appear obvious that a BIO_read() failure
1246 should indicate that a retry should be performed when more
1247 read data is available, this is often not true when using
1248 things like an SSL BIO. During the SSL protocol startup
1249 multiple reads and writes are performed, triggered by any
1250 SSL_read or SSL_write.
1251 So to write code that will transparently handle either a
1256 if (BIO_should_retry(bio))
1258 if (BIO_should_read(bio))
1260 /* call us again when BIO can be read */
1262 if (BIO_should_write(bio))
1264 /* call us again when BIO can be written */
1269 At this point in time only read and write conditions can be
1270 used but in the future I can see the situation for other
1271 conditions, specifically with SSL there could be a condition
1272 of a X509 certificate lookup taking place and so the non-
1273 blocking BIO_read would require a retry when the certificate
1274 lookup subsystem has finished it's lookup. This is all
1275 makes more sense and is easy to use in a event loop type
1277 When using the SSL BIO, either SSL_read() or SSL_write()s
1278 can be called during the protocol startup and things will
1279 still work correctly.
1280 The nice aspect of the use of the BIO_should_retry() macro
1281 is that all the errno codes that indicate a non-fatal error
1282 are encapsulated in one place. The Windows specific error
1283 codes and WSAGetLastError() calls are also hidden from the
1286 Notes on each BIO method.
1287 Normally buffer.h is just required but depending on the
1288 BIO_METHOD, ssl.h or evp.h will also be required.
1290 BIO_METHOD *BIO_s_mem(void);
1291 - BIO_set_mem_buf(BIO *bio, BUF_MEM *bm, int close_flag) -
1292 set the underlying BUF_MEM structure for the BIO to use.
1293 - BIO_get_mem_ptr(BIO *bio, char **pp) - if pp is not NULL,
1294 set it to point to the memory array and return the number
1296 A read/write BIO. Any data written is appended to the
1297 memory array and any read is read from the front. This BIO
1298 can be used for read/write at the same time. BIO_gets() is
1299 supported in the fgets() sense.
1300 BIO_CTRL_INFO can be used to retrieve pointers to the memory
1301 buffer and it's length.
1303 BIO_METHOD *BIO_s_file(void);
1304 - BIO_set_fp(BIO *bio, FILE *fp, int close_flag) - set 'FILE *' to use.
1305 - BIO_get_fp(BIO *bio, FILE **fp) - get the 'FILE *' in use.
1306 - BIO_read_filename(BIO *bio, char *name) - read from file.
1307 - BIO_write_filename(BIO *bio, char *name) - write to file.
1308 - BIO_append_filename(BIO *bio, char *name) - append to file.
1309 This BIO sits over the normal system fread()/fgets() type
1310 functions. Gets() is supported. This BIO in theory could be
1311 used for read and write but it is best to think of each BIO
1312 of this type as either a read or a write BIO, not both.
1314 BIO_METHOD *BIO_s_socket(void);
1315 BIO_METHOD *BIO_s_fd(void);
1316 - BIO_sock_should_retry(int i) - the underlying function
1317 used to determine if a call should be retried; the
1318 argument is the '0' or '-1' returned by the previous BIO
1320 - BIO_fd_should_retry(int i) - same as the
1321 - BIO_sock_should_retry() except that it is different internally.
1322 - BIO_set_fd(BIO *bio, int fd, int close_flag) - set the
1323 file descriptor to use
1324 - BIO_get_fd(BIO *bio, int *fd) - get the file descriptor.
1325 These two methods are very similar. Gets() is not
1326 supported, if you want this functionality, put a
1327 BIO_f_buffer() onto it. This BIO is bi-directional if the
1328 underlying file descriptor is. This is normally the case
1329 for sockets but not the case for stdio descriptors.
1331 BIO_METHOD *BIO_s_null(void);
1332 Read and write as much data as you like, it all disappears
1335 BIO_METHOD *BIO_f_buffer(void);
1336 - BIO_get_buffer_num_lines(BIO *bio) - return the number of
1337 complete lines in the buffer.
1338 - BIO_set_buffer_size(BIO *bio, long size) - set the size of
1340 This type performs input and output buffering. It performs
1341 both at the same time. The size of the buffer can be set
1342 via the set buffer size option. Data buffered for output is
1343 only written when the buffer fills.
1345 BIO_METHOD *BIO_f_ssl(void);
1346 - BIO_set_ssl(BIO *bio, SSL *ssl, int close_flag) - the SSL
1348 - BIO_get_ssl(BIO *bio, SSL **ssl) - get the SSL structure
1350 The SSL bio is a little different from normal BIOs because
1351 the underlying SSL structure is a little different. A SSL
1352 structure performs IO via a read and write BIO. These can
1353 be different and are normally set via the
1354 SSL_set_rbio()/SSL_set_wbio() calls. The SSL_set_fd() calls
1355 are just wrappers that create socket BIOs and then call
1356 SSL_set_bio() where the read and write BIOs are the same.
1357 The BIO_push() operation makes the SSLs IO BIOs the same, so
1358 make sure the BIO pushed is capable of two directional
1359 traffic. If it is not, you will have to install the BIOs
1360 via the more conventional SSL_set_bio() call. BIO_pop() will retrieve
1363 BIO_METHOD *BIO_f_md(void);
1364 - BIO_set_md(BIO *bio, EVP_MD *md) - set the message digest
1366 - BIO_get_md(BIO *bio, EVP_MD **mdp) - return the digest
1367 method in use in mdp, return 0 if not set yet.
1368 - BIO_reset() reinitializes the digest (EVP_DigestInit())
1369 and passes the reset to the underlying BIOs.
1370 All data read or written via BIO_read() or BIO_write() to
1371 this BIO will be added to the calculated digest. This
1372 implies that this BIO is only one directional. If read and
1373 write operations are performed, two separate BIO_f_md() BIOs
1374 are reuqired to generate digests on both the input and the
1375 output. BIO_gets(BIO *bio, char *md, int size) will place the
1376 generated digest into 'md' and return the number of bytes.
1377 The EVP_MAX_MD_SIZE should probably be used to size the 'md'
1378 array. Reading the digest will also reset it.
1380 BIO_METHOD *BIO_f_cipher(void);
1381 - BIO_reset() reinitializes the cipher.
1382 - BIO_flush() should be called when the last bytes have been
1383 output to flush the final block of block ciphers.
1384 - BIO_get_cipher_status(BIO *b), when called after the last
1385 read from a cipher BIO, returns non-zero if the data
1386 decrypted correctly, otherwise, 0.
1387 - BIO_set_cipher(BIO *b, EVP_CIPHER *c, unsigned char *key,
1388 unsigned char *iv, int encrypt) This function is used to
1389 setup a cipher BIO. The length of key and iv are
1390 specified by the choice of EVP_CIPHER. Encrypt is 1 to
1391 encrypt and 0 to decrypt.
1393 BIO_METHOD *BIO_f_base64(void);
1394 - BIO_flush() should be called when the last bytes have been output.
1395 This BIO base64 encodes when writing and base64 decodes when
1396 reading. It will scan the input until a suitable begin line
1397 is found. After reading data, BIO_reset() will reset the
1398 BIO to start scanning again. Do not mix reading and writing
1399 on the same base64 BIO. It is meant as a single stream BIO.
1403 one/both BIO_s_file()
1413 It is easy to mix one and two directional BIOs, all one has
1414 to do is to keep two separate BIO pointers for reading and
1415 writing and be careful about usage of underlying BIOs. The
1416 SSL bio by it's very nature has to be two directional but
1417 the BIO_push() command will push the one BIO into the SSL
1418 BIO for both reading and writing.
1420 The best example program to look at is apps/enc.c and/or perhaps apps/dgst.c.
1423 ==== blowfish.doc ========================================================
1425 The Blowfish library.
1427 Blowfish is a block cipher that operates on 64bit (8 byte) quantities. It
1428 uses variable size key, but 128bit (16 byte) key would normally be considered
1429 good. It can be used in all the modes that DES can be used. This
1430 library implements the ecb, cbc, cfb64, ofb64 modes.
1432 Blowfish is quite a bit faster that DES, and much faster than IDEA or
1433 RC2. It is one of the faster block ciphers.
1435 For all calls that have an 'input' and 'output' variables, they can be the
1438 This library requires the inclusion of 'blowfish.h'.
1440 All of the encryption functions take what is called an BF_KEY as an
1441 argument. An BF_KEY is an expanded form of the Blowfish key.
1442 For all modes of the Blowfish algorithm, the BF_KEY used for
1443 decryption is the same one that was used for encryption.
1445 The define BF_ENCRYPT is passed to specify encryption for the functions
1446 that require an encryption/decryption flag. BF_DECRYPT is passed to
1449 Please note that any of the encryption modes specified in my DES library
1450 could be used with Blowfish. I have only implemented ecb, cbc, cfb64 and
1451 ofb64 for the following reasons.
1452 - ecb is the basic Blowfish encryption.
1453 - cbc is the normal 'chaining' form for block ciphers.
1454 - cfb64 can be used to encrypt single characters, therefore input and output
1455 do not need to be a multiple of 8.
1456 - ofb64 is similar to cfb64 but is more like a stream cipher, not as
1457 secure (not cipher feedback) but it does not have an encrypt/decrypt mode.
1458 - If you want triple Blowfish, thats 384 bits of key and you must be totally
1459 obsessed with security. Still, if you want it, it is simple enough to
1460 copy the function from the DES library and change the des_encrypt to
1461 BF_encrypt; an exercise left for the paranoid reader :-).
1463 The functions are as follows:
1469 BF_set_key converts an 'len' byte key into a BF_KEY.
1470 A 'ks' is an expanded form of the 'key' which is used to
1471 perform actual encryption. It can be regenerated from the Blowfish key
1472 so it only needs to be kept when encryption or decryption is about
1473 to occur. Don't save or pass around BF_KEY's since they
1474 are CPU architecture dependent, 'key's are not. Blowfish is an
1475 interesting cipher in that it can be used with a variable length
1476 key. 'len' is the length of 'key' to be used as the key.
1477 A 'len' of 16 is recomended by me, but blowfish can use upto
1478 72 bytes. As a warning, blowfish has a very very slow set_key
1479 function, it actually runs BF_encrypt 521 times.
1481 void BF_encrypt(unsigned long *data, BF_KEY *key);
1482 void BF_decrypt(unsigned long *data, BF_KEY *key);
1483 These are the Blowfish encryption function that gets called by just
1484 about every other Blowfish routine in the library. You should not
1485 use this function except to implement 'modes' of Blowfish.
1486 I say this because the
1487 functions that call this routine do the conversion from 'char *' to
1488 long, and this needs to be done to make sure 'non-aligned' memory
1489 access do not occur.
1490 Data is a pointer to 2 unsigned long's and key is the
1493 void BF_ecb_encrypt(
1498 This is the basic Electronic Code Book form of Blowfish (in DES this
1499 mode is called Electronic Code Book so I'm going to use the term
1500 for blowfish as well.
1501 Input is encrypted into output using the key represented by
1502 key. Depending on the encrypt, encryption or
1503 decryption occurs. Input is 8 bytes long and output is 8 bytes.
1505 void BF_cbc_encrypt(
1510 unsigned char *ivec,
1512 This routine implements Blowfish in Cipher Block Chaining mode.
1513 Input, which should be a multiple of 8 bytes is encrypted
1514 (or decrypted) to output which will also be a multiple of 8 bytes.
1515 The number of bytes is in length (and from what I've said above,
1516 should be a multiple of 8). If length is not a multiple of 8, bad
1517 things will probably happen. ivec is the initialisation vector.
1518 This function updates iv after each call so that it can be passed to
1519 the next call to BF_cbc_encrypt().
1521 void BF_cfb64_encrypt(
1526 unsigned char *ivec,
1529 This is one of the more useful functions in this Blowfish library, it
1530 implements CFB mode of Blowfish with 64bit feedback.
1531 This allows you to encrypt an arbitrary number of bytes,
1532 you do not require 8 byte padding. Each call to this
1533 routine will encrypt the input bytes to output and then update ivec
1534 and num. Num contains 'how far' we are though ivec.
1535 'Encrypt' is used to indicate encryption or decryption.
1536 CFB64 mode operates by using the cipher to generate a stream
1537 of bytes which is used to encrypt the plain text.
1538 The cipher text is then encrypted to generate the next 64 bits to
1539 be xored (incrementally) with the next 64 bits of plain
1540 text. As can be seen from this, to encrypt or decrypt,
1541 the same 'cipher stream' needs to be generated but the way the next
1542 block of data is gathered for encryption is different for
1543 encryption and decryption.
1545 void BF_ofb64_encrypt(
1550 unsigned char *ivec,
1552 This functions implements OFB mode of Blowfish with 64bit feedback.
1553 This allows you to encrypt an arbitrary number of bytes,
1554 you do not require 8 byte padding. Each call to this
1555 routine will encrypt the input bytes to output and then update ivec
1556 and num. Num contains 'how far' we are though ivec.
1557 This is in effect a stream cipher, there is no encryption or
1560 For reading passwords, I suggest using des_read_pw_string() from my DES library.
1561 To generate a password from a text string, I suggest using MD5 (or MD2) to
1562 produce a 16 byte message digest that can then be passed directly to
1566 For more information about the specific Blowfish modes in this library
1567 (ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the
1568 documentation on my DES library. What is said about DES is directly
1569 applicable for Blowfish.
1572 ==== bn.doc ========================================================
1574 The Big Number library.
1576 #include "bn.h" when using this library.
1578 This big number library was written for use in implementing the RSA and DH
1579 public key encryption algorithms. As such, features such as negative
1580 numbers have not been extensively tested but they should work as expected.
1581 This library uses dynamic memory allocation for storing its data structures
1582 and so there are no limit on the size of the numbers manipulated by these
1583 routines but there is always the requirement to check return codes from
1584 functions just in case a memory allocation error has occurred.
1586 The basic object in this library is a BIGNUM. It is used to hold a single
1587 large integer. This type should be considered opaque and fields should not
1588 be modified or accessed directly.
1589 typedef struct bignum_st
1591 int top; /* Index of last used d. */
1592 BN_ULONG *d; /* Pointer to an array of 'BITS2' bit chunks. */
1593 int max; /* Size of the d array. */
1596 The big number is stored in a malloced array of BN_ULONG's. A BN_ULONG can
1597 be either 16, 32 or 64 bits in size, depending on the 'number of bits'
1599 The 'd' field is this array. 'max' is the size of the 'd' array that has
1600 been allocated. 'top' is the 'last' entry being used, so for a value of 4,
1601 bn.d[0]=4 and bn.top=1. 'neg' is 1 if the number is negative.
1602 When a BIGNUM is '0', the 'd' field can be NULL and top == 0.
1604 Various routines in this library require the use of 'temporary' BIGNUM
1605 variables during their execution. Due to the use of dynamic memory
1606 allocation to create BIGNUMs being rather expensive when used in
1607 conjunction with repeated subroutine calls, the BN_CTX structure is
1608 used. This structure contains BN_CTX BIGNUMs. BN_CTX
1609 is the maximum number of temporary BIGNUMs any publicly exported
1613 typedef struct bignum_ctx
1615 int tos; /* top of stack */
1616 BIGNUM *bn[BN_CTX]; /* The variables */
1619 The functions that follow have been grouped according to function. Most
1620 arithmetic functions return a result in the first argument, sometimes this
1621 first argument can also be an input parameter, sometimes it cannot. These
1622 restrictions are documented.
1624 extern BIGNUM *BN_value_one;
1625 There is one variable defined by this library, a BIGNUM which contains the
1626 number 1. This variable is useful for use in comparisons and assignment.
1630 int BN_num_bits(BIGNUM *a);
1631 This function returns the size of 'a' in bits.
1633 int BN_num_bytes(BIGNUM *a);
1634 This function (macro) returns the size of 'a' in bytes.
1635 For conversion of BIGNUMs to byte streams, this is the number of
1636 bytes the output string will occupy. If the output byte
1637 format specifies that the 'top' bit indicates if the number is
1638 signed, so an extra '0' byte is required if the top bit on a
1639 positive number is being written, it is upto the application to
1640 make this adjustment. Like I said at the start, I don't
1641 really support negative numbers :-).
1643 Creation/Destruction routines.
1646 Return a new BIGNUM object. The number initially has a value of 0. If
1647 there is an error, NULL is returned.
1649 void BN_free(BIGNUM *a);
1652 void BN_clear(BIGNUM *a);
1653 Sets 'a' to a value of 0 and also zeros all unused allocated
1654 memory. This function is used to clear a variable of 'sensitive'
1655 data that was held in it.
1657 void BN_clear_free(BIGNUM *a);
1658 This function zeros the memory used by 'a' and then free()'s it.
1659 This function should be used to BN_free() BIGNUMS that have held
1660 sensitive numeric values like RSA private key values. Both this
1661 function and BN_clear tend to only be used by RSA and DH routines.
1663 BN_CTX *BN_CTX_new(void);
1664 Returns a new BN_CTX. NULL on error.
1666 void BN_CTX_free(BN_CTX *c);
1667 Free a BN_CTX structure. The BIGNUMs in 'c' are BN_clear_free()ed.
1669 BIGNUM *bn_expand(BIGNUM *b, int bits);
1670 This is an internal function that should not normally be used. It
1671 ensures that 'b' has enough room for a 'bits' bit number. It is
1672 mostly used by the various BIGNUM routines. If there is an error,
1673 NULL is returned. if not, 'b' is returned.
1675 BIGNUM *BN_copy(BIGNUM *to, BIGNUM *from);
1676 The 'from' is copied into 'to'. NULL is returned if there is an
1677 error, otherwise 'to' is returned.
1679 BIGNUM *BN_dup(BIGNUM *a);
1680 A new BIGNUM is created and returned containing the value of 'a'.
1681 NULL is returned on error.
1683 Comparison and Test Functions.
1685 int BN_is_zero(BIGNUM *a)
1686 Return 1 if 'a' is zero, else 0.
1689 Return 1 is 'a' is one, else 0.
1692 Return 1 if 'a' == w, else 0. 'w' is a BN_ULONG.
1694 int BN_cmp(BIGNUM *a, BIGNUM *b);
1695 Return -1 if 'a' is less than 'b', 0 if 'a' and 'b' are the same
1696 and 1 is 'a' is greater than 'b'. This is a signed comparison.
1698 int BN_ucmp(BIGNUM *a, BIGNUM *b);
1699 This function is the same as BN_cmp except that the comparison
1700 ignores the sign of the numbers.
1702 Arithmetic Functions
1703 For all of these functions, 0 is returned if there is an error and 1 is
1704 returned for success. The return value should always be checked. eg.
1705 if (!BN_add(r,a,b)) goto err;
1706 Unless explicitly mentioned, the 'return' value can be one of the
1707 'parameters' to the function.
1709 int BN_add(BIGNUM *r, BIGNUM *a, BIGNUM *b);
1710 Add 'a' and 'b' and return the result in 'r'. This is r=a+b.
1712 int BN_sub(BIGNUM *r, BIGNUM *a, BIGNUM *b);
1713 Subtract 'a' from 'b' and put the result in 'r'. This is r=a-b.
1715 int BN_lshift(BIGNUM *r, BIGNUM *a, int n);
1716 Shift 'a' left by 'n' bits. This is r=a*(2^n).
1718 int BN_lshift1(BIGNUM *r, BIGNUM *a);
1719 Shift 'a' left by 1 bit. This form is more efficient than
1720 BN_lshift(r,a,1). This is r=a*2.
1722 int BN_rshift(BIGNUM *r, BIGNUM *a, int n);
1723 Shift 'a' right by 'n' bits. This is r=int(a/(2^n)).
1725 int BN_rshift1(BIGNUM *r, BIGNUM *a);
1726 Shift 'a' right by 1 bit. This form is more efficient than
1727 BN_rshift(r,a,1). This is r=int(a/2).
1729 int BN_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b);
1730 Multiply a by b and return the result in 'r'. 'r' must not be
1731 either 'a' or 'b'. It has to be a different BIGNUM.
1734 int BN_sqr(BIGNUM *r, BIGNUM *a, BN_CTX *ctx);
1735 Multiply a by a and return the result in 'r'. 'r' must not be
1736 'a'. This function is alot faster than BN_mul(r,a,a). This is r=a*a.
1738 int BN_div(BIGNUM *dv, BIGNUM *rem, BIGNUM *m, BIGNUM *d, BN_CTX *ctx);
1739 Divide 'm' by 'd' and return the result in 'dv' and the remainder
1740 in 'rem'. Either of 'dv' or 'rem' can be NULL in which case that
1741 value is not returned. 'ctx' needs to be passed as a source of
1742 temporary BIGNUM variables.
1743 This is dv=int(m/d), rem=m%d.
1745 int BN_mod(BIGNUM *rem, BIGNUM *m, BIGNUM *d, BN_CTX *ctx);
1746 Find the remainder of 'm' divided by 'd' and return it in 'rem'.
1747 'ctx' holds the temporary BIGNUMs required by this function.
1748 This function is more efficient than BN_div(NULL,rem,m,d,ctx);
1751 int BN_mod_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b, BIGNUM *m,BN_CTX *ctx);
1752 Multiply 'a' by 'b' and return the remainder when divided by 'm'.
1753 'ctx' holds the temporary BIGNUMs required by this function.
1756 int BN_mod_exp(BIGNUM *r, BIGNUM *a, BIGNUM *p, BIGNUM *m,BN_CTX *ctx);
1757 Raise 'a' to the 'p' power and return the remainder when divided by
1758 'm'. 'ctx' holds the temporary BIGNUMs required by this function.
1761 int BN_reciprocal(BIGNUM *r, BIGNUM *m, BN_CTX *ctx);
1762 Return the reciprocal of 'm'. 'ctx' holds the temporary variables
1763 required. This function returns -1 on error, otherwise it returns
1764 the number of bits 'r' is shifted left to make 'r' into an integer.
1765 This number of bits shifted is required in BN_mod_mul_reciprocal().
1766 This is r=(1/m)<<(BN_num_bits(m)+1).
1768 int BN_mod_mul_reciprocal(BIGNUM *r, BIGNUM *x, BIGNUM *y, BIGNUM *m,
1769 BIGNUM *i, int nb, BN_CTX *ctx);
1770 This function is used to perform an efficient BN_mod_mul()
1771 operation. If one is going to repeatedly perform BN_mod_mul() with
1772 the same modulus is worth calculating the reciprocal of the modulus
1773 and then using this function. This operation uses the fact that
1774 a/b == a*r where r is the reciprocal of b. On modern computers
1775 multiplication is very fast and big number division is very slow.
1776 'x' is multiplied by 'y' and then divided by 'm' and the remainder
1777 is returned. 'i' is the reciprocal of 'm' and 'nb' is the number
1778 of bits as returned from BN_reciprocal(). Normal usage is as follows.
1779 bn=BN_reciprocal(i,m);
1781 { BN_mod_mul_reciprocal(r,x,y,m,i,bn,ctx); }
1782 This is r=(x*y)%m. Internally it is approximately
1783 r=(x*y)-m*(x*y/m) or r=(x*y)-m*((x*y*i) >> bn)
1784 This function is used in BN_mod_exp() and BN_is_prime().
1786 Assignment Operations
1788 int BN_one(BIGNUM *a)
1789 Set 'a' to hold the value one.
1792 int BN_zero(BIGNUM *a)
1793 Set 'a' to hold the value zero.
1796 int BN_set_word(BIGNUM *a, unsigned long w);
1797 Set 'a' to hold the value of 'w'. 'w' is an unsigned long.
1800 unsigned long BN_get_word(BIGNUM *a);
1801 Returns 'a' in an unsigned long. Not remarkably, often 'a' will
1802 be bigger than a word, in which case 0xffffffffL is returned.
1805 These functions are much more efficient that the normal bignum arithmetic
1808 BN_ULONG BN_mod_word(BIGNUM *a, unsigned long w);
1809 Return the remainder of 'a' divided by 'w'.
1810 This is return(a%w).
1812 int BN_add_word(BIGNUM *a, unsigned long w);
1813 Add 'w' to 'a'. This function does not take the sign of 'a' into
1814 account. This is a+=w;
1818 int BN_is_bit_set(BIGNUM *a, int n);
1819 This function return 1 if bit 'n' is set in 'a' else 0.
1821 int BN_set_bit(BIGNUM *a, int n);
1822 This function sets bit 'n' to 1 in 'a'.
1823 This is a&= ~(1<<n);
1825 int BN_clear_bit(BIGNUM *a, int n);
1826 This function sets bit 'n' to zero in 'a'. Return 0 if less
1827 than 'n' bits in 'a' else 1. This is a&= ~(1<<n);
1829 int BN_mask_bits(BIGNUM *a, int n);
1830 Truncate 'a' to n bits long. This is a&= ~((~0)<<n)
1832 Format conversion routines.
1834 BIGNUM *BN_bin2bn(unsigned char *s, int len,BIGNUM *ret);
1835 This function converts 'len' bytes in 's' into a BIGNUM which
1836 is put in 'ret'. If ret is NULL, a new BIGNUM is created.
1837 Either this new BIGNUM or ret is returned. The number is
1838 assumed to be in bigendian form in 's'. By this I mean that
1839 to 'ret' is created as follows for 'len' == 5.
1840 ret = s[0]*2^32 + s[1]*2^24 + s[2]*2^16 + s[3]*2^8 + s[4];
1841 This function cannot be used to convert negative numbers. It
1842 is always assumed the number is positive. The application
1843 needs to diddle the 'neg' field of th BIGNUM its self.
1844 The better solution would be to save the numbers in ASN.1 format
1845 since this is a defined standard for storing big numbers.
1846 Look at the functions
1848 ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai);
1849 BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai,BIGNUM *bn);
1850 int i2d_ASN1_INTEGER(ASN1_INTEGER *a,unsigned char **pp);
1851 ASN1_INTEGER *d2i_ASN1_INTEGER(ASN1_INTEGER **a,unsigned char **pp,
1854 int BN_bn2bin(BIGNUM *a, unsigned char *to);
1855 This function converts 'a' to a byte string which is put into
1856 'to'. The representation is big-endian in that the most
1857 significant byte of 'a' is put into to[0]. This function
1858 returns the number of bytes used to hold 'a'. BN_num_bytes(a)
1859 would return the same value and can be used to determine how
1860 large 'to' needs to be. If the number is negative, this
1861 information is lost. Since this library was written to
1862 manipulate large positive integers, the inability to save and
1863 restore them is not considered to be a problem by me :-).
1864 As for BN_bin2bn(), look at the ASN.1 integer encoding funtions
1865 for SSLeay. They use BN_bin2bn() and BN_bn2bin() internally.
1867 char *BN_bn2ascii(BIGNUM *a);
1868 This function returns a malloc()ed string that contains the
1869 ascii hexadecimal encoding of 'a'. The number is in bigendian
1870 format with a '-' in front if the number is negative.
1872 int BN_ascii2bn(BIGNUM **bn, char *a);
1873 The inverse of BN_bn2ascii. The function returns the number of
1874 characters from 'a' were processed in generating a the bignum.
1875 error is inticated by 0 being returned. The number is a
1876 hex digit string, optionally with a leading '-'. If *bn
1877 is null, a BIGNUM is created and returned via that variable.
1879 int BN_print_fp(FILE *fp, BIGNUM *a);
1880 'a' is printed to file pointer 'fp'. It is in the same format
1881 that is output from BN_bn2ascii(). 0 is returned on error,
1884 int BN_print(BIO *bp, BIGNUM *a);
1885 Same as BN_print except that the output is done to the SSLeay libraries
1886 BIO routines. BN_print_fp() actually calls this function.
1888 Miscellaneous Routines.
1890 int BN_rand(BIGNUM *rnd, int bits, int top, int bottom);
1891 This function returns in 'rnd' a random BIGNUM that is bits
1892 long. If bottom is 1, the number returned is odd. If top is set,
1893 the top 2 bits of the number are set. This is useful because if
1894 this is set, 2 'n; bit numbers multiplied together will return a 2n
1895 bit number. If top was not set, they could produce a 2n-1 bit
1898 BIGNUM *BN_mod_inverse(BIGNUM *a, BIGNUM *n,BN_CTX *ctx);
1899 This function create a new BIGNUM and returns it. This number
1900 is the inverse mod 'n' of 'a'. By this it is meant that the
1901 returned value 'r' satisfies (a*r)%n == 1. This function is
1902 used in the generation of RSA keys. 'ctx', as per usual,
1903 is used to hold temporary variables that are required by the
1904 function. NULL is returned on error.
1906 int BN_gcd(BIGNUM *r,BIGNUM *a,BIGNUM *b,BN_CTX *ctx);
1907 'r' has the greatest common divisor of 'a' and 'b'. 'ctx' is
1908 used for temporary variables and 0 is returned on error.
1910 int BN_is_prime(BIGNUM *p,int nchecks,void (*callback)(),BN_CTX *ctx,
1912 This function is used to check if a BIGNUM ('p') is prime.
1913 It performs this test by using the Miller-Rabin randomised
1914 primality test. This is a probalistic test that requires a
1915 number of rounds to ensure the number is prime to a high
1916 degree of probability. Since this can take quite some time, a
1917 callback function can be passed and it will be called each
1918 time 'p' passes a round of the prime testing. 'callback' will
1919 be called as follows, callback(1,n,cb_arg) where n is the number of
1920 the round, just passed. As per usual 'ctx' contains temporary
1921 variables used. If ctx is NULL, it does not matter, a local version
1922 will be malloced. This parameter is present to save some mallocing
1923 inside the function but probably could be removed.
1924 0 is returned on error.
1925 'ncheck' is the number of Miller-Rabin tests to run. It is
1926 suggested to use the value 'BN_prime_checks' by default.
1928 BIGNUM *BN_generate_prime(
1933 void (*callback)());
1935 This function is used to generate prime numbers. It returns a
1936 new BIGNUM that has a high probability of being a prime.
1937 'bits' is the number of bits that
1938 are to be in the prime. If 'strong' is true, the returned prime
1939 will also be a strong prime ((p-1)/2 is also prime).
1940 While searching for the prime ('p'), we
1941 can add the requirement that the prime fill the following
1942 condition p%a == rem. This can be used to help search for
1943 primes with specific features, which is required when looking
1944 for primes suitable for use with certain 'g' values in the
1945 Diffie-Hellman key exchange algorithm. If 'a' is NULL,
1946 this condition is not checked. If rem is NULL, rem is assumed
1947 to be 1. Since this search for a prime
1948 can take quite some time, if callback is not NULL, it is called
1949 in the following situations.
1950 We have a suspected prime (from a quick sieve),
1951 callback(0,sus_prime++,cb_arg). Each item to be passed to BN_is_prime().
1952 callback(1,round++,cb_arg). Each successful 'round' in BN_is_prime().
1953 callback(2,round,cb_arg). For each successful BN_is_prime() test.
1958 DSA wants 64*32 to use word mont mul, but RSA wants to use full.
1960 ==== callback.doc ========================================================
1962 Callback functions used in SSLeay.
1964 --------------------------
1967 Each BIO structure can have a callback defined against it. This callback is
1968 called 2 times for each BIO 'function'. It is passed 6 parameters.
1969 BIO_debug_callback() is an example callback which is defined in
1970 crypto/buffer/bio_cb.c and is used in apps/dgst.c This is intended mostly
1971 for debuging or to notify the application of IO.
1973 long BIO_debug_callback(BIO *bio,int cmd,char *argp,int argi,long argl,
1975 bio is the BIO being called, cmd is the type of BIO function being called.
1976 Look at the BIO_CB_* defines in buffer.h. Argp and argi are the arguments
1977 passed to BIO_read(), BIO_write, BIO_gets(), BIO_puts(). In the case of
1978 BIO_ctrl(), argl is also defined. The first time the callback is called,
1979 before the underlying function has been executed, 0 is passed as 'ret', and
1980 if the return code from the callback is not > 0, the call is aborted
1981 and the returned <= 0 value is returned.
1982 The second time the callback is called, the 'cmd' value also has
1983 BIO_CB_RETURN logically 'or'ed with it. The 'ret' value is the value returned
1984 from the actuall function call and whatever the callback returns is returned
1985 from the BIO function.
1987 BIO_set_callback(b,cb) can be used to set the callback function
1988 (b is a BIO), and BIO_set_callback_arg(b,arg) can be used to
1989 set the cb_arg argument in the BIO strucutre. This field is only intended
1990 to be used by application, primarily in the callback function since it is
1991 accessable since the BIO is passed.
1993 --------------------------
1996 The pem library only really uses one type of callback,
1997 static int def_callback(char *buf, int num, int verify);
1998 which is used to return a password string if required.
1999 'buf' is the buffer to put the string in. 'num' is the size of 'buf'
2000 and 'verify' is used to indicate that the password should be checked.
2001 This last flag is mostly used when reading a password for encryption.
2003 For all of these functions, a NULL callback will call the above mentioned
2004 default callback. This default function does not work under Windows 3.1.
2005 For other machines, it will use an application defined prompt string
2006 (EVP_set_pw_prompt(), which defines a library wide prompt string)
2007 if defined, otherwise it will use it's own PEM password prompt.
2008 It will then call EVP_read_pw_string() to get a password from the console.
2009 If your application wishes to use nice fancy windows to retrieve passwords,
2010 replace this function. The callback should return the number of bytes read
2011 into 'buf'. If the number of bytes <= 0, it is considered an error.
2013 Functions that take this callback are listed below. For the 'read' type
2014 functions, the callback will only be required if the PEM data is encrypted.
2016 For the Write functions, normally a password can be passed in 'kstr', of
2017 'klen' bytes which will be used if the 'enc' cipher is not NULL. If
2018 'kstr' is NULL, the callback will be used to retrieve a password.
2020 int PEM_do_header (EVP_CIPHER_INFO *cipher, unsigned char *data,long *len,
2022 char *PEM_ASN1_read_bio(char *(*d2i)(),char *name,BIO *bp,char **x,int (*cb)());
2023 char *PEM_ASN1_read(char *(*d2i)(),char *name,FILE *fp,char **x,int (*cb)());
2024 int PEM_ASN1_write_bio(int (*i2d)(),char *name,BIO *bp,char *x,
2025 EVP_CIPHER *enc,unsigned char *kstr,int klen,int (*callback)());
2026 int PEM_ASN1_write(int (*i2d)(),char *name,FILE *fp,char *x,
2027 EVP_CIPHER *enc,unsigned char *kstr,int klen,int (*callback)());
2028 STACK *PEM_X509_INFO_read(FILE *fp, STACK *sk, int (*cb)());
2029 STACK *PEM_X509_INFO_read_bio(BIO *fp, STACK *sk, int (*cb)());
2031 #define PEM_write_RSAPrivateKey(fp,x,enc,kstr,klen,cb)
2032 #define PEM_write_DSAPrivateKey(fp,x,enc,kstr,klen,cb)
2033 #define PEM_write_bio_RSAPrivateKey(bp,x,enc,kstr,klen,cb)
2034 #define PEM_write_bio_DSAPrivateKey(bp,x,enc,kstr,klen,cb)
2035 #define PEM_read_SSL_SESSION(fp,x,cb)
2036 #define PEM_read_X509(fp,x,cb)
2037 #define PEM_read_X509_REQ(fp,x,cb)
2038 #define PEM_read_X509_CRL(fp,x,cb)
2039 #define PEM_read_RSAPrivateKey(fp,x,cb)
2040 #define PEM_read_DSAPrivateKey(fp,x,cb)
2041 #define PEM_read_PrivateKey(fp,x,cb)
2042 #define PEM_read_PKCS7(fp,x,cb)
2043 #define PEM_read_DHparams(fp,x,cb)
2044 #define PEM_read_bio_SSL_SESSION(bp,x,cb)
2045 #define PEM_read_bio_X509(bp,x,cb)
2046 #define PEM_read_bio_X509_REQ(bp,x,cb)
2047 #define PEM_read_bio_X509_CRL(bp,x,cb)
2048 #define PEM_read_bio_RSAPrivateKey(bp,x,cb)
2049 #define PEM_read_bio_DSAPrivateKey(bp,x,cb)
2050 #define PEM_read_bio_PrivateKey(bp,x,cb)
2051 #define PEM_read_bio_PKCS7(bp,x,cb)
2052 #define PEM_read_bio_DHparams(bp,x,cb)
2053 int i2d_Netscape_RSA(RSA *a, unsigned char **pp, int (*cb)());
2054 RSA *d2i_Netscape_RSA(RSA **a, unsigned char **pp, long length, int (*cb)());
2056 Now you will notice that macros like
2057 #define PEM_write_X509(fp,x) \
2058 PEM_ASN1_write((int (*)())i2d_X509,PEM_STRING_X509,fp, \
2059 (char *)x, NULL,NULL,0,NULL)
2060 Don't do encryption normally. If you want to PEM encrypt your X509 structure,
2061 either just call PEM_ASN1_write directly or just define your own
2062 macro variant. As you can see, this macro just sets all encryption related
2066 --------------------------
2069 #define SSL_set_info_callback(ssl,cb)
2070 #define SSL_CTX_set_info_callback(ctx,cb)
2071 void callback(SSL *ssl,int location,int ret)
2072 This callback is called each time around the SSL_connect()/SSL_accept()
2073 state machine. So it will be called each time the SSL protocol progresses.
2074 It is mostly present for use when debugging. When SSL_connect() or
2075 SSL_accept() return, the location flag is SSL_CB_ACCEPT_EXIT or
2076 SSL_CB_CONNECT_EXIT and 'ret' is the value about to be returned.
2077 Have a look at the SSL_CB_* defines in ssl.h. If an info callback is defined
2078 against the SSL_CTX, it is called unless there is one set against the SSL.
2080 void client_info_callback() in apps/s_client() for an example.
2082 Certificate verification.
2083 void SSL_set_verify(SSL *s, int mode, int (*callback) ());
2084 void SSL_CTX_set_verify(SSL_CTX *ctx,int mode,int (*callback)());
2085 This callback is used to help verify client and server X509 certificates.
2086 It is actually passed to X509_cert_verify(), along with the SSL structure
2087 so you have to read about X509_cert_verify() :-). The SSL_CTX version is used
2088 if the SSL version is not defined. X509_cert_verify() is the function used
2089 by the SSL part of the library to verify certificates. This function is
2090 nearly always defined by the application.
2092 void SSL_CTX_set_cert_verify_cb(SSL_CTX *ctx, int (*cb)(),char *arg);
2093 int callback(char *arg,SSL *s,X509 *xs,STACK *cert_chain);
2094 This call is used to replace the SSLeay certificate verification code.
2095 The 'arg' is kept in the SSL_CTX and is passed to the callback.
2096 If the callback returns 0, the certificate is rejected, otherwise it
2097 is accepted. The callback is replacing the X509_cert_verify() call.
2098 This feature is not often used, but if you wished to implement
2099 some totally different certificate authentication system, this 'hook' is
2102 SSLeay keeps a cache of session-ids against each SSL_CTX. These callbacks can
2103 be used to notify the application when a SSL_SESSION is added to the cache
2104 or to retrieve a SSL_SESSION that is not in the cache from the application.
2105 #define SSL_CTX_sess_set_get_cb(ctx,cb)
2106 SSL_SESSION *callback(SSL *s,char *session_id,int session_id_len,int *copy);
2107 If defined, this callback is called to return the SESSION_ID for the
2108 session-id in 'session_id', of 'session_id_len' bytes. 'copy' is set to 1
2109 if the server is to 'take a copy' of the SSL_SESSION structure. It is 0
2110 if the SSL_SESSION is being 'passed in' so the SSLeay library is now
2111 responsible for 'free()ing' the structure. Basically it is used to indicate
2112 if the reference count on the SSL_SESSION structure needs to be incremented.
2114 #define SSL_CTX_sess_set_new_cb(ctx,cb)
2115 int callback(SSL *s, SSL_SESSION *sess);
2116 When a new connection is established, if the SSL_SESSION is going to be added
2117 to the cache, this callback is called. Return 1 if a 'copy' is required,
2118 otherwise, return 0. This return value just causes the reference count
2119 to be incremented (on return of a 1), this means the application does
2120 not need to worry about incrementing the refernece count (and the
2121 locking that implies in a multi-threaded application).
2123 void SSL_CTX_set_default_passwd_cb(SSL_CTX *ctx,int (*cb)());
2124 This sets the SSL password reading function.
2125 It is mostly used for windowing applications
2126 and used by PEM_read_bio_X509() and PEM_read_bio_RSAPrivateKey()
2127 calls inside the SSL library. The only reason this is present is because the
2128 calls to PEM_* functions is hidden in the SSLeay library so you have to
2129 pass in the callback some how.
2131 #define SSL_CTX_set_client_cert_cb(ctx,cb)
2132 int callback(SSL *s,X509 **x509, EVP_PKEY **pkey);
2133 Called when a client certificate is requested but there is not one set
2134 against the SSL_CTX or the SSL. If the callback returns 1, x509 and
2135 pkey need to point to valid data. The library will free these when
2136 required so if the application wants to keep these around, increment
2137 their reference counts. If 0 is returned, no client cert is
2138 available. If -1 is returned, it is assumed that the callback needs
2139 to be called again at a later point in time. SSL_connect will return
2140 -1 and SSL_want_x509_lookup(ssl) returns true. Remember that
2141 application data can be attached to an SSL structure via the
2142 SSL_set_app_data(SSL *ssl,char *data) call.
2144 --------------------------
2147 int X509_cert_verify(CERTIFICATE_CTX *ctx,X509 *xs, int (*cb)(),
2148 int *error,char *arg,STACK *cert_chain);
2149 int verify_callback(int ok,X509 *xs,X509 *xi,int depth,int error,char *arg,
2152 X509_cert_verify() is used to authenticate X509 certificates. The 'ctx' holds
2153 the details of the various caches and files used to locate certificates.
2154 'xs' is the certificate to verify and 'cb' is the application callback (more
2155 detail later). 'error' will be set to the error code and 'arg' is passed
2156 to the 'cb' callback. Look at the VERIFY_* defines in crypto/x509/x509.h
2158 When ever X509_cert_verify() makes a 'negative' decision about a
2159 certitificate, the callback is called. If everything checks out, the
2160 callback is called with 'VERIFY_OK' or 'VERIFY_ROOT_OK' (for a self
2161 signed cert that is not the passed certificate).
2163 The callback is passed the X509_cert_verify opinion of the certificate
2164 in 'ok', the certificate in 'xs', the issuer certificate in 'xi',
2165 the 'depth' of the certificate in the verification 'chain', the
2166 VERIFY_* code in 'error' and the argument passed to X509_cert_verify()
2167 in 'arg'. cert_chain is a list of extra certs to use if they are not
2170 The callback can be used to look at the error reason, and then return 0
2171 for an 'error' or '1' for ok. This will override the X509_cert_verify()
2172 opinion of the certificates validity. Processing will continue depending on
2173 the return value. If one just wishes to use the callback for informational
2174 reason, just return the 'ok' parameter.
2176 --------------------------
2177 The BN and DH library.
2179 BIGNUM *BN_generate_prime(int bits,int strong,BIGNUM *add,
2180 BIGNUM *rem,void (*callback)(int,int));
2181 int BN_is_prime(BIGNUM *p,int nchecks,void (*callback)(int,int),
2183 Read doc/bn.doc for the description of these 2.
2185 DH *DH_generate_parameters(int prime_len,int generator,
2186 void (*callback)(int,int));
2187 Read doc/bn.doc for the description of the callback, since it is just passed
2188 to BN_generate_prime(), except that it is also called as
2189 callback(3,0) by this function.
2191 --------------------------
2194 void CRYPTO_set_locking_callback(void (*func)(int mode,int type,char *file,
2196 void CRYPTO_set_add_lock_callback(int (*func)(int *num,int mount,
2197 int type,char *file, int line));
2198 void CRYPTO_set_id_callback(unsigned long (*func)(void));
2200 Read threads.doc for info on these ones.
2203 ==== cipher.doc ========================================================
2205 The Cipher subroutines.
2207 These routines require "evp.h" to be included.
2209 These functions are a higher level interface to the various cipher
2210 routines found in this library. As such, they allow the same code to be
2211 used to encrypt and decrypt via different ciphers with only a change
2212 in an initial parameter. These routines also provide buffering for block
2215 These routines all take a pointer to the following structure to specify
2216 which cipher to use. If you wish to use a new cipher with these routines,
2217 you would probably be best off looking an how an existing cipher is
2218 implemented and copying it. At this point in time, I'm not going to go
2219 into many details. This structure should be considered opaque
2221 typedef struct pem_cipher_st
2227 void (*enc_init)(); /* init for encryption */
2228 void (*dec_init)(); /* init for decryption */
2229 void (*do_cipher)(); /* encrypt data */
2232 The type field is the object NID of the cipher type
2233 (read the section on Objects for an explanation of what a NID is).
2234 The cipher block_size is how many bytes need to be passed
2235 to the cipher at a time. Key_len is the
2236 length of the key the cipher requires and iv_len is the length of the
2237 initialisation vector required. enc_init is the function
2238 called to initialise the ciphers context for encryption and dec_init is the
2239 function to initialise for decryption (they need to be different, especially
2240 for the IDEA cipher).
2242 One reason for specifying the Cipher via a pointer to a structure
2243 is that if you only use des-cbc, only the des-cbc routines will
2244 be included when you link the program. If you passed an integer
2245 that specified which cipher to use, the routine that mapped that
2246 integer to a set of cipher functions would cause all the ciphers
2247 to be link into the code. This setup also allows new ciphers
2248 to be added by the application (with some restrictions).
2250 The thirteen ciphers currently defined in this library are
2252 EVP_CIPHER *EVP_des_ecb(); /* DES in ecb mode, iv=0, block=8, key= 8 */
2253 EVP_CIPHER *EVP_des_ede(); /* DES in ecb ede mode, iv=0, block=8, key=16 */
2254 EVP_CIPHER *EVP_des_ede3(); /* DES in ecb ede mode, iv=0, block=8, key=24 */
2255 EVP_CIPHER *EVP_des_cfb(); /* DES in cfb mode, iv=8, block=1, key= 8 */
2256 EVP_CIPHER *EVP_des_ede_cfb(); /* DES in ede cfb mode, iv=8, block=1, key=16 */
2257 EVP_CIPHER *EVP_des_ede3_cfb();/* DES in ede cfb mode, iv=8, block=1, key=24 */
2258 EVP_CIPHER *EVP_des_ofb(); /* DES in ofb mode, iv=8, block=1, key= 8 */
2259 EVP_CIPHER *EVP_des_ede_ofb(); /* DES in ede ofb mode, iv=8, block=1, key=16 */
2260 EVP_CIPHER *EVP_des_ede3_ofb();/* DES in ede ofb mode, iv=8, block=1, key=24 */
2261 EVP_CIPHER *EVP_des_cbc(); /* DES in cbc mode, iv=8, block=8, key= 8 */
2262 EVP_CIPHER *EVP_des_ede_cbc(); /* DES in cbc ede mode, iv=8, block=8, key=16 */
2263 EVP_CIPHER *EVP_des_ede3_cbc();/* DES in cbc ede mode, iv=8, block=8, key=24 */
2264 EVP_CIPHER *EVP_desx_cbc(); /* DES in desx cbc mode,iv=8, block=8, key=24 */
2265 EVP_CIPHER *EVP_rc4(); /* RC4, iv=0, block=1, key=16 */
2266 EVP_CIPHER *EVP_idea_ecb(); /* IDEA in ecb mode, iv=0, block=8, key=16 */
2267 EVP_CIPHER *EVP_idea_cfb(); /* IDEA in cfb mode, iv=8, block=1, key=16 */
2268 EVP_CIPHER *EVP_idea_ofb(); /* IDEA in ofb mode, iv=8, block=1, key=16 */
2269 EVP_CIPHER *EVP_idea_cbc(); /* IDEA in cbc mode, iv=8, block=8, key=16 */
2270 EVP_CIPHER *EVP_rc2_ecb(); /* RC2 in ecb mode, iv=0, block=8, key=16 */
2271 EVP_CIPHER *EVP_rc2_cfb(); /* RC2 in cfb mode, iv=8, block=1, key=16 */
2272 EVP_CIPHER *EVP_rc2_ofb(); /* RC2 in ofb mode, iv=8, block=1, key=16 */
2273 EVP_CIPHER *EVP_rc2_cbc(); /* RC2 in cbc mode, iv=8, block=8, key=16 */
2274 EVP_CIPHER *EVP_bf_ecb(); /* Blowfish in ecb mode,iv=0, block=8, key=16 */
2275 EVP_CIPHER *EVP_bf_cfb(); /* Blowfish in cfb mode,iv=8, block=1, key=16 */
2276 EVP_CIPHER *EVP_bf_ofb(); /* Blowfish in ofb mode,iv=8, block=1, key=16 */
2277 EVP_CIPHER *EVP_bf_cbc(); /* Blowfish in cbc mode,iv=8, block=8, key=16 */
2279 The meaning of the compound names is as follows.
2280 des The base cipher is DES.
2281 idea The base cipher is IDEA
2282 rc4 The base cipher is RC4-128
2283 rc2 The base cipher is RC2-128
2284 ecb Electronic Code Book form of the cipher.
2285 cbc Cipher Block Chaining form of the cipher.
2286 cfb 64 bit Cipher Feedback form of the cipher.
2287 ofb 64 bit Output Feedback form of the cipher.
2288 ede The cipher is used in Encrypt, Decrypt, Encrypt mode. The first
2289 and last keys are the same.
2290 ede3 The cipher is used in Encrypt, Decrypt, Encrypt mode.
2292 All the Cipher routines take a EVP_CIPHER_CTX pointer as an argument.
2293 The state of the cipher is kept in this structure.
2295 typedef struct EVP_CIPHER_Ctx_st
2298 int encrypt; /* encrypt or decrypt */
2299 int buf_len; /* number we have left */
2300 unsigned char buf[8];
2302 .... /* cipher specific stuff */
2306 Cipher is a pointer the the EVP_CIPHER for the current context. The encrypt
2307 flag indicates encryption or decryption. buf_len is the number of bytes
2308 currently being held in buf.
2309 The 'c' union holds the cipher specify context.
2311 The following functions are to be used.
2313 int EVP_read_pw_string(
2318 This function is the same as des_read_pw_string() (des.doc).
2320 void EVP_set_pw_prompt(char *prompt);
2321 This function sets the 'default' prompt to use to use in
2322 EVP_read_pw_string when the prompt parameter is NULL. If the
2323 prompt parameter is NULL, this 'default prompt' feature is turned
2324 off. Be warned, this is a global variable so weird things
2325 will happen if it is used under Win16 and care must be taken
2326 with a multi-threaded version of the library.
2328 char *EVP_get_pw_prompt();
2329 This returns a pointer to the default prompt string. NULL
2335 unsigned char *salt,
2336 unsigned char *data,
2341 This function is used to generate a key and an initialisation vector
2342 for a specified cipher from a key string and a salt. Type
2343 specifies the cipher the 'key' is being generated for. Md is the
2344 message digest algorithm to use to generate the key and iv. The salt
2345 is an optional 8 byte object that is used to help seed the key
2347 If the salt value is NULL, it is just not used. Datal is the
2348 number of bytes to use from 'data' in the key generation.
2349 This function returns the key size for the specified cipher, if
2350 data is NULL, this value is returns and no other
2351 computation is performed. Count is
2352 the number of times to loop around the key generator. I would
2353 suggest leaving it's value as 1. Key and iv are the structures to
2354 place the returning iv and key in. If they are NULL, no value is
2355 generated for that particular value.
2356 The algorithm used is as follows
2358 /* M[] is an array of message digests
2359 * MD() is the message digest function */
2360 M[0]=MD(data . salt);
2361 for (i=1; i<count; i++) M[0]=MD(M[0]);
2364 while (data still needed for key and iv)
2366 M[i]=MD(M[i-1] . data . salt);
2367 for (i=1; i<count; i++) M[i]=MD(M[i]);
2371 If the salt is NULL, it is not used.
2372 The digests are concatenated together.
2373 M = M[0] . M[1] . M[2] .......
2375 For key= 8, iv=8 => key=M[0.. 8], iv=M[ 9 .. 16].
2376 For key=16, iv=0 => key=M[0..16].
2377 For key=16, iv=8 => key=M[0..16], iv=M[17 .. 24].
2378 For key=24, iv=8 => key=M[0..24], iv=M[25 .. 32].
2380 This routine will produce DES-CBC keys and iv that are compatible
2381 with the PKCS-5 standard when md2 or md5 are used. If md5 is
2382 used, the salt is NULL and count is 1, this routine will produce
2383 the password to key mapping normally used with RC4.
2384 I have attempted to logically extend the PKCS-5 standard to
2385 generate keys and iv for ciphers that require more than 16 bytes,
2386 if anyone knows what the correct standard is, please inform me.
2387 When using sha or sha1, things are a bit different under this scheme,
2388 since sha produces a 20 byte digest. So for ciphers requiring
2389 24 bits of data, 20 will come from the first MD and 4 will
2390 come from the second.
2392 I have considered having a separate function so this 'routine'
2393 can be used without the requirement of passing a EVP_CIPHER *,
2394 but I have decided to not bother. If you wish to use the
2395 function without official EVP_CIPHER structures, just declare
2396 a local one and set the key_len and iv_len fields to the
2399 The following routines perform encryption and decryption 'by parts'. By
2400 this I mean that there are groups of 3 routines. An Init function that is
2401 used to specify a cipher and initialise data structures. An Update routine
2402 that does encryption/decryption, one 'chunk' at a time. And finally a
2403 'Final' function that finishes the encryption/decryption process.
2404 All these functions take a EVP_CIPHER pointer to specify which cipher to
2405 encrypt/decrypt with. They also take a EVP_CIPHER_CTX object as an
2406 argument. This structure is used to hold the state information associated
2407 with the operation in progress.
2409 void EVP_EncryptInit(
2410 EVP_CIPHER_CTX *ctx,
2414 This function initialise a EVP_CIPHER_CTX for encryption using the
2415 cipher passed in the 'type' field. The cipher is initialised to use
2416 'key' as the key and 'iv' for the initialisation vector (if one is
2417 required). If the type, key or iv is NULL, the value currently in the
2418 EVP_CIPHER_CTX is reused. So to perform several decrypt
2419 using the same cipher, key and iv, initialise with the cipher,
2420 key and iv the first time and then for subsequent calls,
2421 reuse 'ctx' but pass NULL for type, key and iv. You must make sure
2422 to pass a key that is large enough for a particular cipher. I
2423 would suggest using the EVP_BytesToKey() function.
2425 void EVP_EncryptUpdate(
2426 EVP_CIPHER_CTX *ctx,
2431 This function takes 'inl' bytes from 'in' and outputs bytes
2432 encrypted by the cipher 'ctx' was initialised with into 'out'. The
2433 number of bytes written to 'out' is put into outl. If a particular
2434 cipher encrypts in blocks, less or more bytes than input may be
2435 output. Currently the largest block size used by supported ciphers
2436 is 8 bytes, so 'out' should have room for 'inl+7' bytes. Normally
2437 EVP_EncryptInit() is called once, followed by lots and lots of
2438 calls to EVP_EncryptUpdate, followed by a single EVP_EncryptFinal
2441 void EVP_EncryptFinal(
2442 EVP_CIPHER_CTX *ctx,
2445 Because quite a large number of ciphers are block ciphers, there is
2446 often an incomplete block to write out at the end of the
2447 encryption. EVP_EncryptFinal() performs processing on this last
2448 block. The last block in encoded in such a way that it is possible
2449 to determine how many bytes in the last block are valid. For 8 byte
2450 block size ciphers, if only 5 bytes in the last block are valid, the
2451 last three bytes will be filled with the value 3. If only 2 were
2452 valid, the other 6 would be filled with sixes. If all 8 bytes are
2453 valid, a extra 8 bytes are appended to the cipher stream containing
2454 nothing but 8 eights. These last bytes are output into 'out' and
2455 the number of bytes written is put into 'outl' These last bytes
2456 are output into 'out' and the number of bytes written is put into
2457 'outl'. This form of block cipher finalisation is compatible with
2458 PKCS-5. Please remember that even if you are using ciphers like
2459 RC4 that has no blocking and so the function will not write
2460 anything into 'out', it would still be a good idea to pass a
2461 variable for 'out' that can hold 8 bytes just in case the cipher is
2462 changed some time in the future. It should also be remembered
2463 that the EVP_CIPHER_CTX contains the password and so when one has
2464 finished encryption with a particular EVP_CIPHER_CTX, it is good
2465 practice to zero the structure
2466 (ie. memset(ctx,0,sizeof(EVP_CIPHER_CTX)).
2468 void EVP_DecryptInit(
2469 EVP_CIPHER_CTX *ctx,
2473 This function is basically the same as EVP_EncryptInit() accept that
2474 is prepares the EVP_CIPHER_CTX for decryption.
2476 void EVP_DecryptUpdate(
2477 EVP_CIPHER_CTX *ctx,
2482 This function is basically the same as EVP_EncryptUpdate()
2483 except that it performs decryption. There is one
2484 fundamental difference though. 'out' can not be the same as
2485 'in' for any ciphers with a block size greater than 1 if more
2486 than one call to EVP_DecryptUpdate() will be made. This
2487 is because this routine can hold a 'partial' block between
2488 calls. When a partial block is decrypted (due to more bytes
2489 being passed via this function, they will be written to 'out'
2490 overwriting the input bytes in 'in' that have not been read
2491 yet. From this it should also be noted that 'out' should
2492 be at least one 'block size' larger than 'inl'. This problem
2493 only occurs on the second and subsequent call to
2494 EVP_DecryptUpdate() when using a block cipher.
2496 int EVP_DecryptFinal(
2497 EVP_CIPHER_CTX *ctx,
2500 This function is different to EVP_EncryptFinal in that it 'removes'
2501 any padding bytes appended when the data was encrypted. Due to the
2502 way in which 1 to 8 bytes may have been appended when encryption
2503 using a block cipher, 'out' can end up with 0 to 7 bytes being put
2504 into it. When decoding the padding bytes, it is possible to detect
2505 an incorrect decryption. If the decryption appears to be wrong, 0
2506 is returned. If everything seems ok, 1 is returned. For ciphers
2507 with a block size of 1 (RC4), this function would normally not
2508 return any bytes and would always return 1. Just because this
2509 function returns 1 does not mean the decryption was correct. It
2510 would normally be wrong due to either the wrong key/iv or
2511 corruption of the cipher data fed to EVP_DecryptUpdate().
2512 As for EVP_EncryptFinal, it is a good idea to zero the
2513 EVP_CIPHER_CTX after use since the structure contains the key used
2514 to decrypt the data.
2516 The following Cipher routines are convenience routines that call either
2517 EVP_EncryptXxx or EVP_DecryptXxx depending on weather the EVP_CIPHER_CTX
2518 was setup to encrypt or decrypt.
2520 void EVP_CipherInit(
2521 EVP_CIPHER_CTX *ctx,
2526 This function take arguments that are the same as EVP_EncryptInit()
2527 and EVP_DecryptInit() except for the extra 'enc' flag. If 1, the
2528 EVP_CIPHER_CTX is setup for encryption, if 0, decryption.
2530 void EVP_CipherUpdate(
2531 EVP_CIPHER_CTX *ctx,
2536 Again this function calls either EVP_EncryptUpdate() or
2537 EVP_DecryptUpdate() depending on state in the 'ctx' structure.
2538 As noted for EVP_DecryptUpdate(), when this routine is used
2539 for decryption with block ciphers, 'out' should not be the
2542 int EVP_CipherFinal(
2543 EVP_CIPHER_CTX *ctx,
2544 unsigned char *outm,
2546 This routine call EVP_EncryptFinal() or EVP_DecryptFinal()
2547 depending on the state information in 'ctx'. 1 is always returned
2548 if the mode is encryption, otherwise the return value is the return
2549 value of EVP_DecryptFinal().
2551 ==== cipher.m ========================================================
2553 Date: Tue, 15 Oct 1996 08:16:14 +1000 (EST)
2554 From: Eric Young <eay@mincom.com>
2556 To: Roland Haring <rharing@tandem.cl>
2557 Cc: ssl-users@mincom.com
2558 Subject: Re: Symmetric encryption with ssleay
2559 In-Reply-To: <m0vBpyq-00001aC@tandemnet.tandem.cl>
2560 Message-Id: <Pine.SOL.3.91.961015075623.11394A-100000@orb>
2562 Content-Type: TEXT/PLAIN; charset=US-ASCII
2563 Sender: ssl-lists-owner@mincom.com
2568 On Fri, 11 Oct 1996, Roland Haring wrote:
2570 > Would somebody be so kind to give me the minimum basic
2571 > calls I need to do to libcrypto.a to get some text encrypted
2572 > and decrypted again? ...hopefully with code included to do
2573 > base64 encryption and decryption ... e.g. that sign-it.c code
2574 > posted some while ago was a big help :-) (please, do not point
2575 > me to apps/enc.c where I suspect my Heissenbug to be hidden :-)
2577 Ok, the base64 encoding stuff in 'enc.c' does the wrong thing sometimes
2578 when the data is less than a line long (this is for decoding). I'll dig
2579 up the exact fix today and post it. I am taking longer on 0.6.5 than I
2580 intended so I'll just post this patch.
2582 The documentation to read is in
2584 doc/encode.doc (very sparse :-).
2588 The basic calls to encrypt with say triple DES are
2591 char key[EVP_MAX_KEY_LENGTH];
2592 char iv[EVP_MAX_IV_LENGTH];
2594 unsigned char out[512+8];
2597 /* optional generation of key/iv data from text password using md5
2598 * via an upward compatable verson of PKCS#5. */
2599 EVP_BytesToKey(EVP_des_ede3_cbc,EVP_md5,NULL,passwd,strlen(passwd),
2602 /* Initalise the EVP_CIPHER_CTX */
2603 EVP_EncryptInit(ctx,EVP_des_ede3_cbc,key,iv);
2607 /* This is processing 512 bytes at a time, the bytes are being
2608 * copied into 'out', outl bytes are output. 'out' should not be the
2609 * same as 'in' for reasons mentioned in the documentation. */
2610 EVP_EncryptUpdate(ctx,out,&outl,in,512);
2613 /* Output the last 'block'. If the cipher is a block cipher, the last
2614 * block is encoded in such a way so that a wrong decryption will normally be
2615 * detected - again, one of the PKCS standards. */
2617 EVP_EncryptFinal(ctx,out,&outl);
2619 To decrypt, use the EVP_DecryptXXXXX functions except that EVP_DecryptFinal()
2620 will return 0 if the decryption fails (only detectable on block ciphers).
2626 which does either encryption or decryption depending on an extra
2627 parameter to EVP_CipherInit().
2630 To do the base64 encoding,
2639 where the encoding is quite simple, but the decoding can be a bit more
2640 fun (due to dud input).
2642 EVP_DecodeUpdate() returns -1 for an error on an input line, 0 if the
2643 'last line' was just processed, and 1 if more lines should be submitted.
2645 EVP_DecodeFinal() returns -1 for an error or 1 if things are ok.
2648 EVP_DecodeInit(....)
2651 i=EVP_DecodeUpdate(....);
2652 if (i < 0) goto err;
2654 /* process the data */
2658 EVP_DecodeFinal(....);
2659 /* process the data */
2661 The problem in 'enc.c' is that I was stuff the processing up after the
2662 EVP_DecodeFinal(...) when the for(..) loop was not being run (one line of
2663 base64 data) and this was because 'enc.c' tries to scan over a file until
2664 it hits the first valid base64 encoded line.
2666 hope this helps a bit.
2669 Eric Young | BOOL is tri-state according to Bill Gates.
2670 AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage().
2672 ==== conf.doc ========================================================
2676 The CONF library is a simple set of routines that can be used to configure
2677 programs. It is a superset of the genenv() function with some extra
2680 The library consists of 5 functions.
2682 LHASH *CONF_load(LHASH *config,char *file);
2683 This function is called to load in a configuration file. Multiple
2684 configuration files can be loaded, with each subsequent 'load' overwriting
2685 any already defined 'variables'. If there is an error, NULL is returned.
2686 If config is NULL, a new LHASH structure is created and returned, otherwise
2687 the new data in the 'file' is loaded into the 'config' structure.
2689 void CONF_free(LHASH *config);
2690 This function free()s the data in config.
2692 char *CONF_get_string(LHASH *config,char *section,char *name);
2693 This function returns the string found in 'config' that corresponds to the
2694 'section' and 'name' specified. Classes and the naming system used will be
2695 discussed later in this document. If the variable is not defined, an NULL
2698 long CONF_get_long(LHASH *config,char *section, char *name);
2699 This function is the same as CONF_get_string() except that it converts the
2700 string to an long and returns it. If variable is not a number or the
2701 variable does not exist, 0 is returned. This is a little problematic but I
2702 don't know of a simple way around it.
2704 STACK *CONF_get_section(LHASH *config, char *section);
2705 This function returns a 'stack' of CONF_VALUE items that are all the
2706 items defined in a particular section. DO NOT free() any of the
2707 variable returned. They will disappear when CONF_free() is called.
2710 The configuration file is divided into 'sections'. Each section is started by
2711 a line of the form '[ section ]'. All subsequent variable definitions are
2712 of this section. A variable definition is a simple alpha-numeric name
2713 followed by an '=' and then the data. A section or variable name can be
2714 described by a regular expression of the following form '[A-Za-z0-9_]+'.
2715 The value of the variable is the text after the '=' until the end of the
2716 line, stripped of leading and trailing white space.
2717 At this point I should mention that a '#' is a comment character, \ is the
2718 escape character, and all three types of quote can be used to stop any
2719 special interpretation of the data.
2720 Now when the data is being loaded, variable expansion can occur. This is
2721 done by expanding any $NAME sequences into the value represented by the
2722 variable NAME. If the variable is not in the current section, the different
2723 section can be specified by using the $SECTION::NAME form. The ${NAME} form
2724 also works and is very useful for expanding variables inside strings.
2726 When a variable is looked up, there are 2 special section. 'default', which
2727 is the initial section, and 'ENV' which is the processes environment
2728 variables (accessed via getenv()). When a variable is looked up, it is
2729 first 'matched' with it's section (if one was specified), if this fails, the
2730 'default' section is matched.
2731 If the 'lhash' variable passed was NULL, the environment is searched.
2733 Now why do we bother with sections? So we can have multiple programs using
2734 the same configuration file, or multiple instances of the same program
2735 using different variables. It also provides a nice mechanism to override
2736 the processes environment variables (eg ENV::HOME=/tmp). If there is a
2737 program specific variable missing, we can have default values.
2738 Multiple configuration files can be loaded, with each new value clearing
2739 any predefined values. A system config file can provide 'default' values,
2740 and application/usr specific files can provide overriding values.
2744 # This is a simple example
2745 SSLEAY_HOME = /usr/local/ssl
2746 ENV::PATH = $SSLEAY_HOME/bin:$PATH # override my path
2749 cert_dir = $SSLEAY_HOME/certs # /usr/local/ssl/certs
2752 CIPHER = DES-EDE-MD5:RC4-MD5
2753 USER_CERT = $HOME/${USER}di'r 5' # /home/eay/eaydir 5
2754 USER_CERT = $HOME/\${USER}di\'r # /home/eay/${USER}di'r
2755 USER_CERT = "$HOME/${US"ER}di\'r # $HOME/${USER}di'r
2759 9ab # TEST=123456789ab
2760 TTT = 1234\n\n # TTT=1234<nl><nl>
2764 ==== des.doc ========================================================
2768 Please note that this library was originally written to operate with
2769 eBones, a version of Kerberos that had had encryption removed when it left
2770 the USA and then put back in. As such there are some routines that I will
2771 advise not using but they are still in the library for historical reasons.
2772 For all calls that have an 'input' and 'output' variables, they can be the
2775 This library requires the inclusion of 'des.h'.
2777 All of the encryption functions take what is called a des_key_schedule as an
2778 argument. A des_key_schedule is an expanded form of the des key.
2779 A des_key is 8 bytes of odd parity, the type used to hold the key is a
2780 des_cblock. A des_cblock is an array of 8 bytes, often in this library
2781 description I will refer to input bytes when the function specifies
2782 des_cblock's as input or output, this just means that the variable should
2783 be a multiple of 8 bytes.
2785 The define DES_ENCRYPT is passed to specify encryption, DES_DECRYPT to
2786 specify decryption. The functions and global variable are as follows:
2789 DES keys are supposed to be odd parity. If this variable is set to
2790 a non-zero value, des_set_key() will check that the key has odd
2791 parity and is not one of the known weak DES keys. By default this
2792 variable is turned off;
2794 void des_set_odd_parity(
2796 This function takes a DES key (8 bytes) and sets the parity to odd.
2798 int des_is_weak_key(
2800 This function returns a non-zero value if the DES key passed is a
2801 weak, DES key. If it is a weak key, don't use it, try a different
2802 one. If you are using 'random' keys, the chances of hitting a weak
2803 key are 1/2^52 so it is probably not worth checking for them.
2807 des_key_schedule schedule);
2808 Des_set_key converts an 8 byte DES key into a des_key_schedule.
2809 A des_key_schedule is an expanded form of the key which is used to
2810 perform actual encryption. It can be regenerated from the DES key
2811 so it only needs to be kept when encryption or decryption is about
2812 to occur. Don't save or pass around des_key_schedule's since they
2813 are CPU architecture dependent, DES keys are not. If des_check_key
2814 is non zero, zero is returned if the key has the wrong parity or
2815 the key is a weak key, else 1 is returned.
2819 des_key_schedule schedule);
2820 An alternative name for des_set_key().
2822 int des_rw_mode; /* defaults to DES_PCBC_MODE */
2823 This flag holds either DES_CBC_MODE or DES_PCBC_MODE (default).
2824 This specifies the function to use in the enc_read() and enc_write()
2828 unsigned long *data,
2829 des_key_schedule ks,
2831 This is the DES encryption function that gets called by just about
2832 every other DES routine in the library. You should not use this
2833 function except to implement 'modes' of DES. I say this because the
2834 functions that call this routine do the conversion from 'char *' to
2835 long, and this needs to be done to make sure 'non-aligned' memory
2836 access do not occur. The characters are loaded 'little endian',
2837 have a look at my source code for more details on how I use this
2839 Data is a pointer to 2 unsigned long's and ks is the
2840 des_key_schedule to use. enc, is non zero specifies encryption,
2844 unsigned long *data,
2845 des_key_schedule ks,
2847 This functions is the same as des_encrypt() except that the DES
2848 initial permutation (IP) and final permutation (FP) have been left
2849 out. As for des_encrypt(), you should not use this function.
2850 It is used by the routines in my library that implement triple DES.
2851 IP() des_encrypt2() des_encrypt2() des_encrypt2() FP() is the same
2852 as des_encrypt() des_encrypt() des_encrypt() except faster :-).
2854 void des_ecb_encrypt(
2857 des_key_schedule ks,
2859 This is the basic Electronic Code Book form of DES, the most basic
2860 form. Input is encrypted into output using the key represented by
2861 ks. If enc is non zero (DES_ENCRYPT), encryption occurs, otherwise
2862 decryption occurs. Input is 8 bytes long and output is 8 bytes.
2863 (the des_cblock structure is 8 chars).
2865 void des_ecb3_encrypt(
2868 des_key_schedule ks1,
2869 des_key_schedule ks2,
2870 des_key_schedule ks3,
2872 This is the 3 key EDE mode of ECB DES. What this means is that
2873 the 8 bytes of input is encrypted with ks1, decrypted with ks2 and
2874 then encrypted again with ks3, before being put into output;
2875 C=E(ks3,D(ks2,E(ks1,M))). There is a macro, des_ecb2_encrypt()
2876 that only takes 2 des_key_schedules that implements,
2877 C=E(ks1,D(ks2,E(ks1,M))) in that the final encrypt is done with ks1.
2879 void des_cbc_encrypt(
2883 des_key_schedule ks,
2886 This routine implements DES in Cipher Block Chaining mode.
2887 Input, which should be a multiple of 8 bytes is encrypted
2888 (or decrypted) to output which will also be a multiple of 8 bytes.
2889 The number of bytes is in length (and from what I've said above,
2890 should be a multiple of 8). If length is not a multiple of 8, I'm
2891 not being held responsible :-). ivec is the initialisation vector.
2892 This function does not modify this variable. To correctly implement
2893 cbc mode, you need to do one of 2 things; copy the last 8 bytes of
2894 cipher text for use as the next ivec in your application,
2895 or use des_ncbc_encrypt().
2896 Only this routine has this problem with updating the ivec, all
2897 other routines that are implementing cbc mode update ivec.
2899 void des_ncbc_encrypt(
2903 des_key_schedule sk,
2906 For historical reasons, des_cbc_encrypt() did not update the
2907 ivec with the value requires so that subsequent calls to
2908 des_cbc_encrypt() would 'chain'. This was needed so that the same
2909 'length' values would not need to be used when decrypting.
2910 des_ncbc_encrypt() does the right thing. It is the same as
2911 des_cbc_encrypt accept that ivec is updates with the correct value
2912 to pass in subsequent calls to des_ncbc_encrypt(). I advise using
2913 des_ncbc_encrypt() instead of des_cbc_encrypt();
2915 void des_xcbc_encrypt(
2919 des_key_schedule sk,
2924 This is RSA's DESX mode of DES. It uses inw and outw to
2925 'whiten' the encryption. inw and outw are secret (unlike the iv)
2926 and are as such, part of the key. So the key is sort of 24 bytes.
2927 This is much better than cbc des.
2929 void des_3cbc_encrypt(
2933 des_key_schedule sk1,
2934 des_key_schedule sk2,
2938 This function is flawed, do not use it. I have left it in the
2939 library because it is used in my des(1) program and will function
2940 correctly when used by des(1). If I removed the function, people
2941 could end up unable to decrypt files.
2942 This routine implements outer triple cbc encryption using 2 ks and
2943 2 ivec's. Use des_ede2_cbc_encrypt() instead.
2945 void des_ede3_cbc_encrypt(
2949 des_key_schedule ks1,
2950 des_key_schedule ks2,
2951 des_key_schedule ks3,
2954 This function implements outer triple CBC DES encryption with 3
2955 keys. What this means is that each 'DES' operation
2956 inside the cbc mode is really an C=E(ks3,D(ks2,E(ks1,M))).
2957 Again, this is cbc mode so an ivec is requires.
2958 This mode is used by SSL.
2959 There is also a des_ede2_cbc_encrypt() that only uses 2
2960 des_key_schedule's, the first being reused for the final
2961 encryption. C=E(ks1,D(ks2,E(ks1,M))). This form of triple DES
2962 is used by the RSAref library.
2964 void des_pcbc_encrypt(
2968 des_key_schedule ks,
2971 This is Propagating Cipher Block Chaining mode of DES. It is used
2972 by Kerberos v4. It's parameters are the same as des_ncbc_encrypt().
2974 void des_cfb_encrypt(
2979 des_key_schedule ks,
2982 Cipher Feedback Back mode of DES. This implementation 'feeds back'
2983 in numbit blocks. The input (and output) is in multiples of numbits
2984 bits. numbits should to be a multiple of 8 bits. Length is the
2985 number of bytes input. If numbits is not a multiple of 8 bits,
2986 the extra bits in the bytes will be considered padding. So if
2987 numbits is 12, for each 2 input bytes, the 4 high bits of the
2988 second byte will be ignored. So to encode 72 bits when using
2989 a numbits of 12 take 12 bytes. To encode 72 bits when using
2990 numbits of 9 will take 16 bytes. To encode 80 bits when using
2991 numbits of 16 will take 10 bytes. etc, etc. This padding will
2992 apply to both input and output.
2995 void des_cfb64_encrypt(
2999 des_key_schedule ks,
3003 This is one of the more useful functions in this DES library, it
3004 implements CFB mode of DES with 64bit feedback. Why is this
3005 useful you ask? Because this routine will allow you to encrypt an
3006 arbitrary number of bytes, no 8 byte padding. Each call to this
3007 routine will encrypt the input bytes to output and then update ivec
3008 and num. num contains 'how far' we are though ivec. If this does
3009 not make much sense, read more about cfb mode of DES :-).
3011 void des_ede3_cfb64_encrypt(
3015 des_key_schedule ks1,
3016 des_key_schedule ks2,
3017 des_key_schedule ks3,
3021 Same as des_cfb64_encrypt() accept that the DES operation is
3022 triple DES. As usual, there is a macro for
3023 des_ede2_cfb64_encrypt() which reuses ks1.
3025 void des_ofb_encrypt(
3030 des_key_schedule ks,
3032 This is a implementation of Output Feed Back mode of DES. It is
3033 the same as des_cfb_encrypt() in that numbits is the size of the
3034 units dealt with during input and output (in bits).
3036 void des_ofb64_encrypt(
3040 des_key_schedule ks,
3043 The same as des_cfb64_encrypt() except that it is Output Feed Back
3046 void des_ede3_ofb64_encrypt(
3050 des_key_schedule ks1,
3051 des_key_schedule ks2,
3052 des_key_schedule ks3,
3055 Same as des_ofb64_encrypt() accept that the DES operation is
3056 triple DES. As usual, there is a macro for
3057 des_ede2_ofb64_encrypt() which reuses ks1.
3059 int des_read_pw_string(
3064 This routine is used to get a password from the terminal with echo
3065 turned off. Buf is where the string will end up and length is the
3066 size of buf. Prompt is a string presented to the 'user' and if
3067 verify is set, the key is asked for twice and unless the 2 copies
3068 match, an error is returned. A return code of -1 indicates a
3069 system error, 1 failure due to use interaction, and 0 is success.
3071 unsigned long des_cbc_cksum(
3075 des_key_schedule ks,
3077 This function produces an 8 byte checksum from input that it puts in
3078 output and returns the last 4 bytes as a long. The checksum is
3079 generated via cbc mode of DES in which only the last 8 byes are
3080 kept. I would recommend not using this function but instead using
3081 the EVP_Digest routines, or at least using MD5 or SHA. This
3082 function is used by Kerberos v4 so that is why it stays in the
3089 This is my fast version of the unix crypt(3) function. This version
3090 takes only a small amount of space relative to other fast
3091 crypt() implementations. This is different to the normal crypt
3092 in that the third parameter is the buffer that the return value
3093 is written into. It needs to be at least 14 bytes long. This
3094 function is thread safe, unlike the normal crypt.
3099 This function calls des_fcrypt() with a static array passed as the
3100 third parameter. This emulates the normal non-thread safe semantics
3103 void des_string_to_key(
3106 This function takes str and converts it into a DES key. I would
3107 recommend using MD5 instead and use the first 8 bytes of output.
3108 When I wrote the first version of these routines back in 1990, MD5
3109 did not exist but I feel these routines are still sound. This
3110 routines is compatible with the one in MIT's libdes.
3112 void des_string_to_2keys(
3116 This function takes str and converts it into 2 DES keys.
3117 I would recommend using MD5 and using the 16 bytes as the 2 keys.
3118 I have nothing against these 2 'string_to_key' routines, it's just
3119 that if you say that your encryption key is generated by using the
3120 16 bytes of an MD5 hash, every-one knows how you generated your
3123 int des_read_password(
3127 This routine combines des_read_pw_string() with des_string_to_key().
3129 int des_read_2passwords(
3134 This routine combines des_read_pw_string() with des_string_to_2key().
3136 void des_random_seed(
3138 This routine sets a starting point for des_random_key().
3140 void des_random_key(
3142 This function return a random key. Make sure to 'seed' the random
3143 number generator (with des_random_seed()) before using this function.
3144 I personally now use a MD5 based random number system.
3150 des_key_schedule ks,
3152 This function will write to a file descriptor the encrypted data
3153 from buf. This data will be preceded by a 4 byte 'byte count' and
3154 will be padded out to 8 bytes. The encryption is either CBC of
3155 PCBC depending on the value of des_rw_mode. If it is DES_PCBC_MODE,
3156 pcbc is used, if DES_CBC_MODE, cbc is used. The default is to use
3163 des_key_schedule ks,
3165 This routines read stuff written by des_enc_read() and decrypts it.
3166 I have used these routines quite a lot but I don't believe they are
3167 suitable for non-blocking io. If you are after a full
3168 authentication/encryption over networks, have a look at SSL instead.
3170 unsigned long des_quad_cksum(
3176 This is a function from Kerberos v4 that is not anything to do with
3177 DES but was needed. It is a cksum that is quicker to generate than
3178 des_cbc_cksum(); I personally would use MD5 routines now.
3181 Quite a bit of the following information has been taken from
3184 Electronic funds transfer - Requirements for interfaces,
3185 Part 5.2: Modes of operation for an n-bit block cipher algorithm
3188 There are several different modes in which DES can be used, they are
3191 Electronic Codebook Mode (ECB) (des_ecb_encrypt())
3192 - 64 bits are enciphered at a time.
3193 - The order of the blocks can be rearranged without detection.
3194 - The same plaintext block always produces the same ciphertext block
3195 (for the same key) making it vulnerable to a 'dictionary attack'.
3196 - An error will only affect one ciphertext block.
3198 Cipher Block Chaining Mode (CBC) (des_cbc_encrypt())
3199 - a multiple of 64 bits are enciphered at a time.
3200 - The CBC mode produces the same ciphertext whenever the same
3201 plaintext is encrypted using the same key and starting variable.
3202 - The chaining operation makes the ciphertext blocks dependent on the
3203 current and all preceding plaintext blocks and therefore blocks can not
3205 - The use of different starting variables prevents the same plaintext
3206 enciphering to the same ciphertext.
3207 - An error will affect the current and the following ciphertext blocks.
3209 Cipher Feedback Mode (CFB) (des_cfb_encrypt())
3210 - a number of bits (j) <= 64 are enciphered at a time.
3211 - The CFB mode produces the same ciphertext whenever the same
3212 plaintext is encrypted using the same key and starting variable.
3213 - The chaining operation makes the ciphertext variables dependent on the
3214 current and all preceding variables and therefore j-bit variables are
3215 chained together and can not be rearranged.
3216 - The use of different starting variables prevents the same plaintext
3217 enciphering to the same ciphertext.
3218 - The strength of the CFB mode depends on the size of k (maximal if
3219 j == k). In my implementation this is always the case.
3220 - Selection of a small value for j will require more cycles through
3221 the encipherment algorithm per unit of plaintext and thus cause
3222 greater processing overheads.
3223 - Only multiples of j bits can be enciphered.
3224 - An error will affect the current and the following ciphertext variables.
3226 Output Feedback Mode (OFB) (des_ofb_encrypt())
3227 - a number of bits (j) <= 64 are enciphered at a time.
3228 - The OFB mode produces the same ciphertext whenever the same
3229 plaintext enciphered using the same key and starting variable. More
3230 over, in the OFB mode the same key stream is produced when the same
3231 key and start variable are used. Consequently, for security reasons
3232 a specific start variable should be used only once for a given key.
3233 - The absence of chaining makes the OFB more vulnerable to specific attacks.
3234 - The use of different start variables values prevents the same
3235 plaintext enciphering to the same ciphertext, by producing different
3237 - Selection of a small value for j will require more cycles through
3238 the encipherment algorithm per unit of plaintext and thus cause
3239 greater processing overheads.
3240 - Only multiples of j bits can be enciphered.
3241 - OFB mode of operation does not extend ciphertext errors in the
3242 resultant plaintext output. Every bit error in the ciphertext causes
3243 only one bit to be in error in the deciphered plaintext.
3244 - OFB mode is not self-synchronising. If the two operation of
3245 encipherment and decipherment get out of synchronism, the system needs
3246 to be re-initialised.
3247 - Each re-initialisation should use a value of the start variable
3248 different from the start variable values used before with the same
3249 key. The reason for this is that an identical bit stream would be
3250 produced each time from the same parameters. This would be
3251 susceptible to a ' known plaintext' attack.
3253 Triple ECB Mode (des_ecb3_encrypt())
3254 - Encrypt with key1, decrypt with key2 and encrypt with key3 again.
3255 - As for ECB encryption but increases the key length to 168 bits.
3256 There are theoretic attacks that can be used that make the effective
3257 key length 112 bits, but this attack also requires 2^56 blocks of
3258 memory, not very likely, even for the NSA.
3259 - If both keys are the same it is equivalent to encrypting once with
3261 - If the first and last key are the same, the key length is 112 bits.
3262 There are attacks that could reduce the key space to 55 bit's but it
3263 requires 2^56 blocks of memory.
3264 - If all 3 keys are the same, this is effectively the same as normal
3267 Triple CBC Mode (des_ede3_cbc_encrypt())
3268 - Encrypt with key1, decrypt with key2 and then encrypt with key3.
3269 - As for CBC encryption but increases the key length to 168 bits with
3270 the same restrictions as for triple ecb mode.
3272 ==== digest.doc ========================================================
3275 The Message Digest subroutines.
3277 These routines require "evp.h" to be included.
3279 These functions are a higher level interface to the various message digest
3280 routines found in this library. As such, they allow the same code to be
3281 used to digest via different algorithms with only a change in an initial
3282 parameter. They are basically just a front-end to the MD2, MD5, SHA
3286 These routines all take a pointer to the following structure to specify
3287 which message digest algorithm to use.
3288 typedef struct evp_md_st
3297 int required_pkey_type; /*EVP_PKEY_xxx */
3302 If additional message digest algorithms are to be supported, a structure of
3303 this type needs to be declared and populated and then the Digest routines
3304 can be used with that algorithm. The type field is the object NID of the
3305 digest type (read the section on Objects for an explanation). The pkey_type
3306 is the Object type to use when the a message digest is generated by there
3307 routines and then is to be signed with the pkey algorithm. Md_size is
3308 the size of the message digest returned. Init, update
3309 and final are the relevant functions to perform the message digest function
3310 by parts. One reason for specifying the message digest to use via this
3311 mechanism is that if you only use md5, only the md5 routines will
3312 be included in you linked program. If you passed an integer
3313 that specified which message digest to use, the routine that mapped that
3314 integer to a set of message digest functions would cause all the message
3315 digests functions to be link into the code. This setup also allows new
3316 message digest functions to be added by the application.
3318 The six message digests defined in this library are
3320 EVP_MD *EVP_md2(void); /* RSA sign/verify */
3321 EVP_MD *EVP_md5(void); /* RSA sign/verify */
3322 EVP_MD *EVP_sha(void); /* RSA sign/verify */
3323 EVP_MD *EVP_sha1(void); /* RSA sign/verify */
3324 EVP_MD *EVP_dss(void); /* DSA sign/verify */
3325 EVP_MD *EVP_dss1(void); /* DSA sign/verify */
3327 All the message digest routines take a EVP_MD_CTX pointer as an argument.
3328 The state of the message digest is kept in this structure.
3330 typedef struct pem_md_ctx_st
3334 unsigned char base[4]; /* this is used in my library as a
3335 * 'pointer' to all union elements
3343 The Digest functions are as follows.
3345 void EVP_DigestInit(
3348 This function is used to initialise the EVP_MD_CTX. The message
3349 digest that will associated with 'ctx' is specified by 'type'.
3351 void EVP_DigestUpdate(
3353 unsigned char *data,
3355 This function is used to pass more data to the message digest
3356 function. 'cnt' bytes are digested from 'data'.
3358 void EVP_DigestFinal(
3362 This function finishes the digestion and puts the message digest
3363 into 'md'. The length of the message digest is put into len;
3364 EVP_MAX_MD_SIZE is the size of the largest message digest that
3365 can be returned from this function. Len can be NULL if the
3366 size of the digest is not required.
3369 ==== encode.doc ========================================================
3372 void EVP_EncodeInit(EVP_ENCODE_CTX *ctx);
3373 void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx,unsigned char *out,
3374 int *outl,unsigned char *in,int inl);
3375 void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx,unsigned char *out,int *outl);
3376 int EVP_EncodeBlock(unsigned char *t, unsigned char *f, int n);
3378 void EVP_DecodeInit(EVP_ENCODE_CTX *ctx);
3379 int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx,unsigned char *out,int *outl,
3380 unsigned char *in, int inl);
3381 int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned
3382 char *out, int *outl);
3383 int EVP_DecodeBlock(unsigned char *t, unsigned
3387 ==== envelope.doc ========================================================
3389 The following routines are use to create 'digital' envelopes.
3390 By this I mean that they perform various 'higher' level cryptographic
3391 functions. Have a read of 'cipher.doc' and 'digest.doc' since those
3392 routines are used by these functions.
3393 cipher.doc contains documentation about the cipher part of the
3394 envelope library and digest.doc contatins the description of the
3395 message digests supported.
3397 To 'sign' a document involves generating a message digest and then encrypting
3398 the digest with an private key.
3400 #define EVP_SignInit(a,b) EVP_DigestInit(a,b)
3401 #define EVP_SignUpdate(a,b,c) EVP_DigestUpdate(a,b,c)
3402 Due to the fact this operation is basically just an extended message
3403 digest, the first 2 functions are macro calls to Digest generating
3411 This finalisation function finishes the generation of the message
3412 digest and then encrypts the digest (with the correct message digest
3413 object identifier) with the EVP_PKEY private key. 'ctx' is the message digest
3414 context. 'md' will end up containing the encrypted message digest. This
3415 array needs to be EVP_PKEY_size(pkey) bytes long. 's' will actually
3416 contain the exact length. 'pkey' of course is the private key. It is
3417 one of EVP_PKEY_RSA or EVP_PKEY_DSA type.
3418 If there is an error, 0 is returned, otherwise 1.
3420 Verify is used to check an signed message digest.
3422 #define EVP_VerifyInit(a,b) EVP_DigestInit(a,b)
3423 #define EVP_VerifyUpdate(a,b,c) EVP_DigestUpdate(a,b,c)
3424 Since the first step is to generate a message digest, the first 2 functions
3427 int EVP_VerifyFinal(
3432 This function finishes the generation of the message digest and then
3433 compares it with the supplied encrypted message digest. 'md' contains the
3434 's' bytes of encrypted message digest. 'pkey' is used to public key decrypt
3435 the digest. It is then compared with the message digest just generated.
3436 If they match, 1 is returned else 0.
3438 int EVP_SealInit(EVP_CIPHER_CTX *ctx, EVP_CIPHER *type, unsigned char **ek,
3439 int *ekl, unsigned char *iv, EVP_PKEY **pubk, int npubk);
3440 Must have at least one public key, error is 0. I should also mention that
3441 the buffers pointed to by 'ek' need to be EVP_PKEY_size(pubk[n]) is size.
3443 #define EVP_SealUpdate(a,b,c,d,e) EVP_EncryptUpdate(a,b,c,d,e)
3444 void EVP_SealFinal(EVP_CIPHER_CTX *ctx,unsigned char *out,int *outl);
3447 int EVP_OpenInit(EVP_CIPHER_CTX *ctx,EVP_CIPHER *type,unsigned char *ek,
3448 int ekl,unsigned char *iv,EVP_PKEY *priv);
3451 #define EVP_OpenUpdate(a,b,c,d,e) EVP_DecryptUpdate(a,b,c,d,e)
3453 int EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl);
3454 Decrypt final return code
3457 ==== error.doc ========================================================
3461 The 'error' system I've implemented is intended to server 2 purpose, to
3462 record the reason why a command failed and to record where in the libraries
3463 the failure occurred. It is more or less setup to record a 'trace' of which
3464 library components were being traversed when the error occurred.
3466 When an error is recorded, it is done so a as single unsigned long which is
3467 composed of three parts. The top byte is the 'library' number, the middle
3468 12 bytes is the function code, and the bottom 12 bits is the 'reason' code.
3470 Each 'library', or should a say, 'section' of the SSLeay library has a
3471 different unique 'library' error number. Each function in the library has
3472 a number that is unique for that library. Each 'library' also has a number
3473 for each 'error reason' that is only unique for that 'library'.
3475 Due to the way these error routines record a 'error trace', there is an
3476 array per thread that is used to store the error codes.
3477 The various functions in this library are used to access
3478 and manipulate this array.
3480 void ERR_put_error(int lib, int func,int reason);
3481 This routine records an error in library 'lib', function 'func'
3482 and reason 'reason'. As errors get 'put' into the buffer, they wrap
3483 around and overwrite old errors if too many are written. It is assumed
3484 that the last errors are the most important.
3486 unsigned long ERR_get_error(void );
3487 This function returns the last error added to the error buffer.
3488 In effect it is popping the value off the buffer so repeated calls will
3489 continue to return values until there are no more errors to return in which
3492 unsigned long ERR_peek_error(void );
3493 This function returns the value of the last error added to the
3494 error buffer but does not 'pop' it from the buffer.
3496 void ERR_clear_error(void );
3497 This function clears the error buffer, discarding all unread
3500 While the above described error system obviously produces lots of different
3501 error number, a method for 'reporting' these errors in a human readable
3502 form is required. To achieve this, each library has the option of
3503 'registering' error strings.
3505 typedef struct ERR_string_data_st
3507 unsigned long error;
3511 The 'ERR_STRING_DATA' contains an error code and the corresponding text
3512 string. To add new function error strings for a library, the
3513 ERR_STRING_DATA needs to be 'registered' with the library.
3515 void ERR_load_strings(unsigned long lib,ERR_STRING_DATA *err);
3516 This function 'registers' the array of ERR_STRING_DATA pointed to by
3517 'err' as error text strings for the error library 'lib'.
3519 void ERR_free_strings(void);
3520 This function free()s all the loaded error strings.
3522 char *ERR_error_string(unsigned long error,char *buf);
3523 This function returns a text string that is a human readable
3524 version of the error represented by 'error'. Buff should be at least 120
3525 bytes long and if it is NULL, the return value is a pointer to a static
3526 variable that will contain the error string, otherwise 'buf' is returned.
3527 If there is not a text string registered for a particular error, a text
3528 string containing the error number is returned instead.
3530 void ERR_print_errors(BIO *bp);
3531 void ERR_print_errors_fp(FILE *fp);
3532 This function is a convenience routine that prints the error string
3533 for each error until all errors have been accounted for.
3535 char *ERR_lib_error_string(unsigned long e);
3536 char *ERR_func_error_string(unsigned long e);
3537 char *ERR_reason_error_string(unsigned long e);
3538 The above three functions return the 3 different components strings for the
3539 error 'e'. ERR_error_string() uses these functions.
3541 void ERR_load_ERR_strings(void );
3542 This function 'registers' the error strings for the 'ERR' module.
3544 void ERR_load_crypto_strings(void );
3545 This function 'register' the error strings for just about every
3546 library in the SSLeay package except for the SSL routines. There is no
3547 need to ever register any error text strings and you will probably save in
3548 program size. If on the other hand you do 'register' all errors, it is
3549 quite easy to determine why a particular routine failed.
3551 As a final footnote as to why the error system is designed as it is.
3552 1) I did not want a single 'global' error code.
3553 2) I wanted to know which subroutine a failure occurred in.
3554 3) For Windows NT etc, it should be simple to replace the 'key' routines
3555 with code to pass error codes back to the application.
3556 4) I wanted the option of meaningful error text strings.
3558 Late breaking news - the changes to support threads.
3560 Each 'thread' has an 'ERR_STATE' state associated with it.
3561 ERR_STATE *ERR_get_state(void ) will return the 'state' for the calling
3564 ERR_remove_state(unsigned long pid); will 'free()' this state. If pid == 0
3565 the current 'thread/process' will have it's error state removed.
3566 If you do not remove the error state of a thread, this could be considered a
3567 form of memory leak, so just after 'reaping' a thread that has died,
3568 call ERR_remove_state(pid).
3570 Have a read of thread.doc for more details for what is required for
3571 multi-threading support. All the other error routines will
3572 work correctly when using threads.
3575 ==== idea.doc ========================================================
3578 IDEA is a block cipher that operates on 64bit (8 byte) quantities. It
3579 uses a 128bit (16 byte) key. It can be used in all the modes that DES can
3580 be used. This library implements the ecb, cbc, cfb64 and ofb64 modes.
3582 For all calls that have an 'input' and 'output' variables, they can be the
3585 This library requires the inclusion of 'idea.h'.
3587 All of the encryption functions take what is called an IDEA_KEY_SCHEDULE as an
3588 argument. An IDEA_KEY_SCHEDULE is an expanded form of the idea key.
3589 For all modes of the IDEA algorithm, the IDEA_KEY_SCHEDULE used for
3590 decryption is different to the one used for encryption.
3592 The define IDEA_ENCRYPT is passed to specify encryption for the functions
3593 that require an encryption/decryption flag. IDEA_DECRYPT is passed to
3594 specify decryption. For some mode there is no encryption/decryption
3595 flag since this is determined by the IDEA_KEY_SCHEDULE.
3597 So to encrypt you would do the following
3598 idea_set_encrypt_key(key,encrypt_ks);
3599 idea_ecb_encrypt(...,encrypt_ks);
3600 idea_cbc_encrypt(....,encrypt_ks,...,IDEA_ENCRYPT);
3603 idea_set_encrypt_key(key,encrypt_ks);
3604 idea_set_decrypt_key(encrypt_ks,decrypt_ks);
3605 idea_ecb_encrypt(...,decrypt_ks);
3606 idea_cbc_encrypt(....,decrypt_ks,...,IDEA_DECRYPT);
3608 Please note that any of the encryption modes specified in my DES library
3609 could be used with IDEA. I have only implemented ecb, cbc, cfb64 and
3610 ofb64 for the following reasons.
3611 - ecb is the basic IDEA encryption.
3612 - cbc is the normal 'chaining' form for block ciphers.
3613 - cfb64 can be used to encrypt single characters, therefore input and output
3614 do not need to be a multiple of 8.
3615 - ofb64 is similar to cfb64 but is more like a stream cipher, not as
3616 secure (not cipher feedback) but it does not have an encrypt/decrypt mode.
3617 - If you want triple IDEA, thats 384 bits of key and you must be totally
3618 obsessed with security. Still, if you want it, it is simple enough to
3619 copy the function from the DES library and change the des_encrypt to
3620 idea_encrypt; an exercise left for the paranoid reader :-).
3622 The functions are as follows:
3624 void idea_set_encrypt_key(
3626 IDEA_KEY_SCHEDULE *ks);
3627 idea_set_encrypt_key converts a 16 byte IDEA key into an
3628 IDEA_KEY_SCHEDULE. The IDEA_KEY_SCHEDULE is an expanded form of
3629 the key which can be used to perform IDEA encryption.
3630 An IDEA_KEY_SCHEDULE is an expanded form of the key which is used to
3631 perform actual encryption. It can be regenerated from the IDEA key
3632 so it only needs to be kept when encryption is about
3633 to occur. Don't save or pass around IDEA_KEY_SCHEDULE's since they
3634 are CPU architecture dependent, IDEA keys are not.
3636 void idea_set_decrypt_key(
3637 IDEA_KEY_SCHEDULE *encrypt_ks,
3638 IDEA_KEY_SCHEDULE *decrypt_ks);
3639 This functions converts an encryption IDEA_KEY_SCHEDULE into a
3640 decryption IDEA_KEY_SCHEDULE. For all decryption, this conversion
3641 of the key must be done. In some modes of IDEA, an
3642 encryption/decryption flag is also required, this is because these
3643 functions involve block chaining and the way this is done changes
3644 depending on which of encryption of decryption is being done.
3645 Please note that there is no quick way to generate the decryption
3646 key schedule other than generating the encryption key schedule and
3650 unsigned long *data,
3651 IDEA_KEY_SCHEDULE *ks);
3652 This is the IDEA encryption function that gets called by just about
3653 every other IDEA routine in the library. You should not use this
3654 function except to implement 'modes' of IDEA. I say this because the
3655 functions that call this routine do the conversion from 'char *' to
3656 long, and this needs to be done to make sure 'non-aligned' memory
3657 access do not occur.
3658 Data is a pointer to 2 unsigned long's and ks is the
3659 IDEA_KEY_SCHEDULE to use. Encryption or decryption depends on the
3662 void idea_ecb_encrypt(
3663 unsigned char *input,
3664 unsigned char *output,
3665 IDEA_KEY_SCHEDULE *ks);
3666 This is the basic Electronic Code Book form of IDEA (in DES this
3667 mode is called Electronic Code Book so I'm going to use the term
3668 for idea as well :-).
3669 Input is encrypted into output using the key represented by
3670 ks. Depending on the IDEA_KEY_SCHEDULE, encryption or
3671 decryption occurs. Input is 8 bytes long and output is 8 bytes.
3673 void idea_cbc_encrypt(
3674 unsigned char *input,
3675 unsigned char *output,
3677 IDEA_KEY_SCHEDULE *ks,
3678 unsigned char *ivec,
3680 This routine implements IDEA in Cipher Block Chaining mode.
3681 Input, which should be a multiple of 8 bytes is encrypted
3682 (or decrypted) to output which will also be a multiple of 8 bytes.
3683 The number of bytes is in length (and from what I've said above,
3684 should be a multiple of 8). If length is not a multiple of 8, bad
3685 things will probably happen. ivec is the initialisation vector.
3686 This function updates iv after each call so that it can be passed to
3687 the next call to idea_cbc_encrypt().
3689 void idea_cfb64_encrypt(
3693 des_key_schedule ks,
3697 This is one of the more useful functions in this IDEA library, it
3698 implements CFB mode of IDEA with 64bit feedback.
3699 This allows you to encrypt an arbitrary number of bytes,
3700 you do not require 8 byte padding. Each call to this
3701 routine will encrypt the input bytes to output and then update ivec
3702 and num. Num contains 'how far' we are though ivec.
3703 Enc is used to indicate encryption or decryption.
3704 One very important thing to remember is that when decrypting, use
3705 the encryption form of the key.
3706 CFB64 mode operates by using the cipher to
3707 generate a stream of bytes which is used to encrypt the plain text.
3708 The cipher text is then encrypted to generate the next 64 bits to
3709 be xored (incrementally) with the next 64 bits of plain
3710 text. As can be seen from this, to encrypt or decrypt,
3711 the same 'cipher stream' needs to be generated but the way the next
3712 block of data is gathered for encryption is different for
3713 encryption and decryption. What this means is that to encrypt
3714 idea_set_encrypt_key(key,ks);
3715 idea_cfb64_encrypt(...,ks,..,IDEA_ENCRYPT)
3717 idea_set_encrypt_key(key,ks)
3718 idea_cfb64_encrypt(...,ks,...,IDEA_DECRYPT)
3719 Note: The same IDEA_KEY_SCHEDULE but different encryption flags.
3720 For idea_cbc or idea_ecb, idea_set_decrypt_key() would need to be
3721 used to generate the IDEA_KEY_SCHEDULE for decryption.
3722 The reason I'm stressing this point is that I just wasted 3 hours
3723 today trying to decrypt using this mode and the decryption form of
3726 void idea_ofb64_encrypt(
3730 des_key_schedule ks,
3733 This functions implements OFB mode of IDEA with 64bit feedback.
3734 This allows you to encrypt an arbitrary number of bytes,
3735 you do not require 8 byte padding. Each call to this
3736 routine will encrypt the input bytes to output and then update ivec
3737 and num. Num contains 'how far' we are though ivec.
3738 This is in effect a stream cipher, there is no encryption or
3739 decryption mode. The same key and iv should be used to
3740 encrypt and decrypt.
3742 For reading passwords, I suggest using des_read_pw_string() from my DES library.
3743 To generate a password from a text string, I suggest using MD5 (or MD2) to
3744 produce a 16 byte message digest that can then be passed directly to
3745 idea_set_encrypt_key().
3748 For more information about the specific IDEA modes in this library
3749 (ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the
3750 documentation on my DES library. What is said about DES is directly
3751 applicable for IDEA.
3754 ==== legal.doc ========================================================
3756 From eay@mincom.com Thu Jun 27 00:25:45 1996
3757 Received: by orb.mincom.oz.au id AA15821
3758 (5.65c/IDA-1.4.4 for eay); Wed, 26 Jun 1996 14:25:45 +1000
3759 Date: Wed, 26 Jun 1996 14:25:45 +1000 (EST)
3760 From: Eric Young <eay@mincom.oz.au>
3762 To: Ken Toll <ktoll@ren.digitalage.com>
3763 Cc: Eric Young <eay@mincom.oz.au>, ssl-talk@netscape.com
3764 Subject: Re: Unidentified subject!
3765 In-Reply-To: <9606261950.ZM28943@ren.digitalage.com>
3766 Message-Id: <Pine.SOL.3.91.960626131156.28573K-100000@orb>
3768 Content-Type: TEXT/PLAIN; charset=US-ASCII
3773 This is a little off topic but since SSLeay is a free implementation of
3774 the SSLv2 protocol, I feel it is worth responding on the topic of if it
3775 is actually legal for Americans to use free cryptographic software.
3777 On Wed, 26 Jun 1996, Ken Toll wrote:
3778 > Is the U.S the only country that SSLeay cannot be used commercially
3779 > (because of RSAref) or is that going to be an issue with every country
3780 > that a client/server application (non-web browser/server) is deployed
3783 >From what I understand, the software patents that apply to algorithms
3784 like RSA and DH only apply in the USA. The IDEA algorithm I believe is
3785 patened in europe (USA?), but considing how little it is used by other SSL
3786 implementations, it quite easily be left out of the SSLeay build
3787 (this can be done with a compile flag).
3789 Actually if the RSA patent did apply outside the USA, it could be rather
3790 interesting since RSA is not alowed to let RSA toolkits outside of the USA
3791 [1], and since these are the only forms that they will alow the algorithm
3792 to be used in, it would mean that non-one outside of the USA could produce
3793 public key software which would be a very strong statment for
3794 international patent law to make :-). This logic is a little flawed but
3795 it still points out some of the more interesting permutations of USA
3796 patent law and ITAR restrictions.
3798 Inside the USA there is also the unresolved issue of RC4/RC2 which were
3799 made public on sci.crypt in Sep 1994 (RC4) and Feb 1996 (RC2). I have
3800 copies of the origional postings if people are interested. RSA I believe
3801 claim that they were 'trade-secrets' and that some-one broke an NDA in
3802 revealing them. Other claim they reverse engineered the algorithms from
3803 compiled binaries. If the algorithms were reverse engineered, I believe
3804 RSA had no legal leg to stand on. If an NDA was broken, I don't know.
3805 Regardless, RSA, I believe, is willing to go to court over the issue so
3806 licencing is probably the best idea, or at least talk to them.
3807 If there are people who actually know more about this, pease let me know, I
3808 don't want to vilify or spread miss-information if I can help it.
3810 If you are not producing a web browser, it is easy to build SSLeay with
3811 RC2/RC4 removed. Since RC4 is the defacto standard cipher in
3812 all web software (and it is damn fast) it is more or less required for
3813 www use. For non www use of SSL, especially for an application where
3814 interoperability with other vendors is not critical just leave it out.
3816 Removing IDEA, RC2 and RC4 would only leave DES and Triple DES but
3817 they should be ok. Considing that Triple DES can encrypt at rates of
3818 410k/sec on a pentium 100, and 940k/sec on a P6/200, this is quite
3819 reasonable performance. Single DES clocks in at 1160k/s and 2467k/s
3820 respectivly is actually quite fast for those not so paranoid (56 bit key).[1]
3822 > Is it possible to get a certificate for commercial use outside of the U.S.?
3825 Thawte Consulting issues certificates (they are the people who sell the
3826 Sioux httpd server and are based in South Africa)
3827 Verisign will issue certificates for Sioux (sold from South Africa), so this
3828 proves that they will issue certificate for OS use if they are
3829 happy with the quality of the software.
3831 (The above mentioned companies just the ones that I know for sure are issuing
3832 certificates outside the USA).
3834 There is always the point that if you are using SSL for an intra net,
3835 SSLeay provides programs that can be used so you can issue your own
3836 certificates. They need polishing but at least it is a good starting point.
3838 I am not doing anything outside Australian law by implementing these
3839 algorithms (to the best of my knowedge). It is another example of how
3840 the world legal system does not cope with the internet very well.
3842 I may start making shared libraries available (I have now got DLL's for
3843 Windows). This will mean that distributions into the usa could be
3844 shipped with a version with a reduced cipher set and the versions outside
3845 could use the DLL/shared library with all the ciphers (and without RSAref).
3847 This could be completly hidden from the application, so this would not
3848 even require a re-linking.
3850 This is the reverse of what people were talking about doing to get around
3851 USA export regulations :-)
3855 [1]: The RSAref2.0 tookit is available on at least 3 ftp sites in Europe
3856 and one in South Africa.
3858 [2]: Since I always get questions when I post benchmark numbers :-),
3859 DES performace figures are in 1000's of bytes per second in cbc
3860 mode using an 8192 byte buffer. The pentium 100 was running Windows NT
3861 3.51 DLLs and the 686/200 was running NextStep.
3862 I quote pentium 100 benchmarks because it is basically the
3863 'entry level' computer that most people buy for personal use.
3864 Windows 95 is the OS shipping on those boxes, so I'll give
3865 NT numbers (the same Win32 runtime environment). The 686
3866 numbers are present as an indication of where we will be in a
3869 Eric Young | BOOL is tri-state according to Bill Gates.
3870 AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage().
3874 ==== lhash.doc ========================================================
3878 I wrote this library in 1991 and have since forgotten why I called it lhash.
3879 It implements a hash table from an article I read at the
3880 time from 'Communications of the ACM'. What makes this hash
3881 table different is that as the table fills, the hash table is
3882 increased (or decreased) in size via realloc().
3883 When a 'resize' is done, instead of all hashes being redistributed over
3884 twice as many 'buckets', one bucket is split. So when an 'expand' is done,
3885 there is only a minimal cost to redistribute some values. Subsequent
3886 inserts will cause more single 'bucket' redistributions but there will
3887 never be a sudden large cost due to redistributing all the 'buckets'.
3889 The state for a particular hash table is kept in the LHASH structure.
3890 The LHASH structure also records statistics about most aspects of accessing
3891 the hash table. This is mostly a legacy of my writing this library for
3892 the reasons of implementing what looked like a nice algorithm rather than
3893 for a particular software product.
3895 Internal stuff you probably don't want to know about.
3896 The decision to increase or decrease the hash table size is made depending
3897 on the 'load' of the hash table. The load is the number of items in the
3898 hash table divided by the size of the hash table. The default values are
3899 as follows. If (hash->up_load < load) => expand.
3900 if (hash->down_load > load) => contract. The 'up_load' has a default value of
3901 1 and 'down_load' has a default value of 2. These numbers can be modified
3902 by the application by just playing with the 'up_load' and 'down_load'
3903 variables. The 'load' is kept in a form which is multiplied by 256. So
3904 hash->up_load=8*256; will cause a load of 8 to be set.
3906 If you are interested in performance the field to watch is
3907 num_comp_calls. The hash library keeps track of the 'hash' value for
3908 each item so when a lookup is done, the 'hashes' are compared, if
3909 there is a match, then a full compare is done, and
3910 hash->num_comp_calls is incremented. If num_comp_calls is not equal
3911 to num_delete plus num_retrieve it means that your hash function is
3912 generating hashes that are the same for different values. It is
3913 probably worth changing your hash function if this is the case because
3914 even if your hash table has 10 items in a 'bucked', it can be searched
3915 with 10 'unsigned long' compares and 10 linked list traverses. This
3916 will be much less expensive that 10 calls to you compare function.
3919 unsigned long (*hash)(),
3921 This function is used to create a new LHASH structure. It is passed
3922 function pointers that are used to store and retrieve values passed
3923 into the hash table. The 'hash'
3924 function is a hashing function that will return a hashed value of
3925 it's passed structure. 'cmp' is passed 2 parameters, it returns 0
3926 is they are equal, otherwise, non zero.
3927 If there are any problems (usually malloc failures), NULL is
3928 returned, otherwise a new LHASH structure is returned. The
3929 hash value is normally truncated to a power of 2, so make sure
3930 that your hash function returns well mixed low order bits.
3934 This function free()s a LHASH structure. If there is malloced
3935 data in the hash table, it will not be freed. Consider using the
3936 lh_doall function to deallocate any remaining entries in the hash
3942 This function inserts the data pointed to by data into the lh hash
3943 table. If there is already and entry in the hash table entry, the
3944 value being replaced is returned. A NULL is returned if the new
3945 entry does not clash with an entry already in the table (the normal
3946 case) or on a malloc() failure (perhaps I should change this....).
3947 The 'char *data' is exactly what is passed to the hash and
3948 comparison functions specified in lh_new().
3953 This routine deletes an entry from the hash table. The value being
3954 deleted is returned. NULL is returned if there is no such value in
3960 If 'data' is in the hash table it is returned, else NULL is
3961 returned. The way these routines would normally be uses is that a
3962 dummy structure would have key fields populated and then
3963 ret=lh_retrieve(hash,&dummy);. Ret would now be a pointer to a fully
3964 populated structure.
3968 void (*func)(char *a));
3969 This function will, for every entry in the hash table, call function
3970 'func' with the data item as parameters.
3971 This function can be quite useful when used as follows.
3972 void cleanup(STUFF *a)
3974 lh_doall(hash,cleanup);
3976 This can be used to free all the entries, lh_free() then
3977 cleans up the 'buckets' that point to nothing. Be careful
3978 when doing this. If you delete entries from the hash table,
3979 in the call back function, the table may decrease in size,
3980 moving item that you are
3981 currently on down lower in the hash table. This could cause
3982 some entries to be skipped. The best solution to this problem
3983 is to set lh->down_load=0 before you start. This will stop
3984 the hash table ever being decreased in size.
3988 void(*func)(char *a,char *arg));
3990 This function is the same as lh_doall except that the function
3991 called will be passed 'arg' as the second argument.
3993 unsigned long lh_strhash(
3995 This function is a demo string hashing function. Since the LHASH
3996 routines would normally be passed structures, this routine would
3997 not normally be passed to lh_new(), rather it would be used in the
3998 function passed to lh_new().
4000 The next three routines print out various statistics about the state of the
4001 passed hash table. These numbers are all kept in the lhash structure.
4006 This function prints out statistics on the size of the hash table,
4007 how many entries are in it, and the number and result of calls to
4008 the routines in this library.
4013 For each 'bucket' in the hash table, the number of entries is
4016 void lh_node_usage_stats(
4019 This function prints out a short summary of the state of the hash
4020 table. It prints what I call the 'load' and the 'actual load'.
4021 The load is the average number of data items per 'bucket' in the
4022 hash table. The 'actual load' is the average number of items per
4023 'bucket', but only for buckets which contain entries. So the
4024 'actual load' is the average number of searches that will need to
4025 find an item in the hash table, while the 'load' is the average number
4026 that will be done to record a miss.
4028 ==== md2.doc ========================================================
4031 MD2 is a message digest algorithm that can be used to condense an arbitrary
4032 length message down to a 16 byte hash. The functions all need to be passed
4033 a MD2_CTX which is used to hold the MD2 context during multiple MD2_Update()
4034 function calls. The normal method of use for this library is as follows
4042 This library requires the inclusion of 'md2.h'.
4044 The main negative about MD2 is that it is slow, especially when compared
4047 The functions are as follows:
4051 This function needs to be called to initiate a MD2_CTX structure for
4056 unsigned char *data;
4058 This updates the message digest context being generated with 'len'
4059 bytes from the 'data' pointer. The number of bytes can be any
4065 This function is called when a message digest of the data digested
4066 with MD2_Update() is wanted. The message digest is put in the 'md'
4067 array and is MD2_DIGEST_LENGTH (16) bytes long.
4073 This function performs a MD2_Init(), followed by a MD2_Update()
4074 followed by a MD2_Final() (using a local MD2_CTX).
4075 The resulting digest is put into 'md' if it is not NULL.
4076 Regardless of the value of 'md', the message
4077 digest is returned from the function. If 'md' was NULL, the message
4078 digest returned is being stored in a static structure.
4080 ==== md5.doc ========================================================
4083 MD5 is a message digest algorithm that can be used to condense an arbitrary
4084 length message down to a 16 byte hash. The functions all need to be passed
4085 a MD5_CTX which is used to hold the MD5 context during multiple MD5_Update()
4086 function calls. This library also contains random number routines that are
4089 The normal method of use for this library is as follows
4097 This library requires the inclusion of 'md5.h'.
4099 The functions are as follows:
4103 This function needs to be called to initiate a MD5_CTX structure for
4108 unsigned char *data;
4110 This updates the message digest context being generated with 'len'
4111 bytes from the 'data' pointer. The number of bytes can be any
4117 This function is called when a message digest of the data digested
4118 with MD5_Update() is wanted. The message digest is put in the 'md'
4119 array and is MD5_DIGEST_LENGTH (16) bytes long.
4125 This function performs a MD5_Init(), followed by a MD5_Update()
4126 followed by a MD5_Final() (using a local MD5_CTX).
4127 The resulting digest is put into 'md' if it is not NULL.
4128 Regardless of the value of 'md', the message
4129 digest is returned from the function. If 'md' was NULL, the message
4130 digest returned is being stored in a static structure.
4133 ==== memory.doc ========================================================
4135 In the interests of debugging SSLeay, there is an option to compile
4136 using some simple memory leak checking.
4138 All malloc(), free() and realloc() calls in SSLeay now go via
4139 Malloc(), Free() and Realloc() (except those in crypto/lhash).
4141 If CRYPTO_MDEBUG is defined, these calls are #defined to
4142 CRYPTO_malloc(), CRYPTO_free() and CRYPTO_realloc().
4143 If it is not defined, they are #defined to malloc(), free() and realloc().
4145 the CRYPTO_malloc() routines by default just call the underlying library
4148 If CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON) is called, memory leak detection is
4149 turned on. CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_OFF) turns it off.
4151 When turned on, each Malloc() or Realloc() call is recored along with the file
4152 and line number from where the call was made. (This is done using the
4153 lhash library which always uses normal system malloc(3) routines).
4155 void CRYPTO_mem_leaks(BIO *b);
4156 void CRYPTO_mem_leaks_fp(FILE *fp);
4157 These both print out the list of memory that has not been free()ed.
4158 This will probably be rather hard to read, but if you look for the 'top level'
4159 structure allocation, this will often give an idea as to what is not being
4160 free()ed. I don't expect people to use this stuff normally.
4162 ==== ca.1 ========================================================
4164 From eay@orb.mincom.oz.au Thu Dec 28 23:56:45 1995
4165 Received: by orb.mincom.oz.au id AA07374
4166 (5.65c/IDA-1.4.4 for eay); Thu, 28 Dec 1995 13:56:45 +1000
4167 Date: Thu, 28 Dec 1995 13:56:45 +1000 (EST)
4168 From: Eric Young <eay@mincom.oz.au>
4170 To: sameer <sameer@c2.org>
4171 Cc: ssleay@mincom.oz.au
4173 In-Reply-To: <199512230440.UAA23410@infinity.c2.org>
4174 Message-Id: <Pine.SOL.3.91.951228133525.7269A-100000@orb>
4176 Content-Type: TEXT/PLAIN; charset=US-ASCII
4180 On Fri, 22 Dec 1995, sameer wrote:
4181 > I could use documentation on 'ca'. Thanks.
4184 The ca program uses the ssleay.conf file for most of its configuration
4188 -verbose - Talk alot while doing things
4189 -config file - A config file. If you don't want to use the
4191 -name arg - The particular CA definition to use
4192 In the config file, the section to use for parameters. This lets
4193 multiple setups to be contained in the one file. By default, the
4194 default_ca variable is looked up in the [ ca ] section. So in the
4195 shipped ssleay.conf, the CA definition used is CA_default. It could be
4197 -gencrl days - Generate a new CRL, days is when the next CRL is due
4198 This will generate a new certificate revocion list.
4199 -days arg - number of days to certify the certificate for
4200 When certifiying certificates, this is the number of days to use.
4201 -md arg - md to use, one of md2, md5, sha or sha1
4202 -policy arg - The CA 'policy' to support
4203 I'll describe this later, but there are 2 policies definied in the
4205 -keyfile arg - PEM RSA private key file
4206 -key arg - key to decode the RSA private key if it is encrypted
4207 since we need to keep the CA's RSA key encrypted
4208 -cert - The CA certificate
4209 -in file - The input PEM encoded certificate request(s)
4210 -out file - Where to put the output file(s)
4211 -outdir dir - Where to put output certificates
4212 The -out options concatinates all the output certificied
4213 certificates to one file, -outdir puts them in a directory,
4214 named by serial number.
4215 -infiles .... - The last argument, requests to process
4216 The certificate requests to process, -in is the same.
4218 Just about all the above have default values defined in ssleay.conf.
4220 The key variables in ssleay.conf are (for the pariticular '-name' being
4221 used, in the default, it is CA_default).
4223 dir is where all the CA database stuff is kept.
4224 certs is where all the previously issued certificates are kept.
4225 The database is a simple text database containing the following tab separated
4227 status: a value of 'R' - revoked, 'E' -expired or 'V' valid.
4228 issued date: When the certificate was certified.
4229 revoked date: When it was revoked, blank if not revoked.
4230 serial number: The certificate serial number.
4231 certificate: Where the certificate is located.
4232 CN: The name of the certificate.
4234 The demo file has quite a few made up values it it. The last 2 were
4235 added by the ca program and are acurate.
4236 The CA program does not update the 'certificate' file correctly right now.
4237 The serial field should be unique as should the CN/status combination.
4238 The ca program checks these at startup. What still needs to be
4239 wrtten is a program to 'regenerate' the data base file from the issued
4240 certificate list (and a CRL list).
4242 Back to the CA_default variables.
4244 Most of the variables are commented.
4246 policy is the default policy.
4248 Ok for policies, they define the order and which fields must be present
4249 in the certificate request and what gets filled in.
4253 means that the country name must match the CA certificate.
4254 organizationalUnitName = optional
4255 The org.Unit,Name does not have to be present and
4256 commonName = supplied
4257 commonName must be supplied in the certificate request.
4259 For the 'policy_match' polocy, the order of the attributes in the
4260 generated certiticate would be
4264 organizationalUnitName
4268 Have a play, it sort of makes sense. If you think about how the persona
4269 requests operate, it is similar to the 'policy_match' policy and the
4270 'policy_anything' is similar to what versign is doing.
4272 I hope this helps a bit. Some backend scripts are definitly needed to
4273 update the database and to make certificate revocion easy. All
4274 certificates issued should also be kept forever (or until they expire?)
4277 eric (who has to run off an buy some cheap knee pads for the caving in 4
4281 Eric Young | Signature removed since it was generating
4282 AARNet: eay@mincom.oz.au | more followups than the message contents :-)
4285 ==== ms3-ca.doc ========================================================
4287 Date: Mon, 9 Jun 97 08:00:33 +0200
4288 From: Holger.Reif@PrakInf.TU-Ilmenau.DE (Holger Reif)
4290 Organization: TU Ilmenau, Fak. IA, FG Telematik
4291 Content-Length: 14575
4295 Loading client certs into MSIE 3.01
4296 ===================================
4298 This document contains all the information necessary to successfully set up
4299 some scripts to issue client certs to Microsoft Internet Explorer. It
4300 includes the required knowledge about the model MSIE uses for client
4301 certification and includes complete sample scripts ready to play with. The
4302 scripts were tested against a modified ca program of SSLeay 0.6.6 and should
4303 work with the regular ca program that comes with version 0.8.0. I haven't
4304 tested against MSIE 4.0
4306 You can use the information contained in this document in either way you
4307 want. However if you feel it saved you a lot of time I ask you to be as fair
4308 as to mention my name: Holger Reif <reif@prakinf.tu-ilmenau.de>.
4310 1.) The model used by MSIE
4311 --------------------------
4313 The Internet Explorer doesn't come with a embedded engine for installing
4314 client certs like Netscape's Navigator. It rather uses the CryptoAPI (CAPI)
4315 defined by Microsoft. CAPI comes with WindowsNT 4.0 or is installed together
4316 with Internet Explorer since 3.01. The advantage of this approach is a higher
4317 flexibility because the certificates in the (per user) system open
4318 certificate store may be used by other applications as well. The drawback
4319 however is that you need to do a bit more work to get a client cert issued.
4321 CAPI defines functions which will handle basic cryptographic work, eg.
4322 generating keys, encrypting some data, signing text or building a certificate
4323 request. The procedure is as follows: A CAPI function generates you a key
4324 pair and saves it into the certificate store. After that one builds a
4325 Distinguished Name. Together with that key pair another CAPI function forms a
4326 PKCS#10 request which you somehow need to submit to a CA. Finally the issued
4327 cert is given to a yet another CAPI function which saves it into the
4330 The certificate store with the user's keys and certs is in the registry. You
4331 will find it under HKEY_CURRENT_USER/Software/Microsoft/Cryptography/ (I
4332 leave it to you as a little exercise to figure out what all the entries mean
4333 ;-). Note that the keys are protected only with the user's usual Windows
4336 2.) The practical usage
4337 -----------------------
4339 Unfortunatly since CAPI is a system API you can't access its functions from
4340 HTML code directly. For this purpose Microsoft provides a wrapper called
4341 certenr3.dll. This DLL accesses the CAPI functions and provides an interface
4342 usable from Visual Basic Script. One needs to install that library on the
4343 computer which wants to have client cert. The easiest way is to load it as an
4344 ActiveX control (certenr3.dll is properly authenticode signed by MS ;-). If
4345 you have ever enrolled e cert request at a CA you will have installed it.
4347 At time of writing certenr3.dll is contained in
4348 http://www.microsoft.com/workshop/prog/security/csa/certenr3.exe. It comes
4349 with an README file which explains the available functions. It is labeled
4350 beta but every CA seems to use it anyway. The license.txt allows you the
4351 usage for your own purposes (as far as I understood) and a somehow limited
4354 The two functions of main interest are GenerateKeyPair and AcceptCredentials.
4355 For complete explanation of all possible parameters see the README file. Here
4356 are only minimal required parameters and their values.
4358 GenerateKeyPair(sessionID, FASLE, szName, 0, "ClientAuth", TRUE, FALSE, 1)
4359 - sessionID is a (locally to that computer) unique string to correlate the
4360 generated key pair with a cert installed later.
4361 - szName is the DN of the form "C=DE; S=Thueringen; L=Ilmenau; CN=Holger
4362 Reif; 1.2.840.113549.1.9.1=reif@prakinf.tu-ilmenau.de". Note that S is the
4363 abreviation for StateOrProvince. The recognized abreviation include CN, O, C,
4364 OU, G, I, L, S, T. If the abreviation is unknown (eg. for PKCS#9 email addr)
4365 you need to use the full object identifier. The starting point for searching
4366 them could be crypto/objects.h since all OIDs know to SSLeay are listed
4368 - note: the possible ninth parameter which should give a default name to the
4369 certificate storage location doesn't seem to work. Changes to the constant
4370 values in the call above doesn't seem to make sense. You can't generate
4371 PKCS#10 extensions with that function.
4373 The result of GenerateKeyPair is the base64 encoded PKCS#10 request. However
4374 it has a little strange format that SSLeay doesn't accept. (BTW I feel the
4375 decision of rejecting that format as standard conforming.) It looks like
4377 1st line with 76 chars
4378 2nd line with 76 chars
4380 (n-2)th line with 76 chars
4381 (n-1)th line contains a multiple of 4 chars less then 76 (possible
4383 (n)th line has zero or 4 chars (then with 1 or 2 equal signs - the
4384 original text's lenght wasn'T a multiple of 3)
4385 The line separator has two chars: 0x0d 0x0a
4387 AcceptCredentials(sessionID, credentials, 0, FALSE)
4388 - sessionID needs to be the same as while generating the key pair
4389 - credentials is the base64 encoded PKCS#7 object containing the cert.
4391 CRL's and CA certs are not required simply just the client cert. (It seems to
4392 me that both are not even checked somehow.) The only format of the base64
4393 encoded object I succesfully used was all characters in a very long string
4394 without line feeds or carriage returns. (Hey, it doesn't matter, only a
4397 The result should be S_OK. For error handling see the example that comes with
4400 A note about ASN.1 character encodings. certenr3.dll seems to know only about
4401 2 of them: UniversalString and PrintableString. First it is definitely wrong
4402 for an email address which is IA5STRING (checked by ssleay's ca). Second
4403 unfortunately MSIE (at least until version 3.02) can't handle UniversalString
4404 correctly - they just blow up you cert store! Therefore ssleay's ca (starting
4405 from version 0.8.0) tries to convert the encodings automatically to IA5STRING
4406 or TeletexString. The beef is it will work only for the latin-1 (western)
4407 charset. Microsoft still has to do abit of homework...
4412 At least you need two steps: generating the key & request and then installing
4413 the certificate. A real world CA would have some more steps involved, eg.
4414 accepting some license. Note that both scripts shown below are just
4415 experimental state without any warrenty!
4417 First how to generate a request. Note that we can't use a static page because
4418 of the sessionID. I generate it from system time plus pid and hope it is
4419 unique enough. Your are free to feed it through md5 to get more impressive
4420 ID's ;-) Then the intended text is read in with sed which inserts the
4423 -----BEGIN ms-enroll.cgi-----
4425 SESSION_ID=`date '+%y%m%d%H%M%S'`$$
4426 echo Content-type: text/html
4428 sed s/template_for_sessId/$SESSION_ID/ <<EOF
4430 <TITLE>Certificate Enrollment Test Page</TITLE>
4434 classid="clsid:33BEC9E0-F78F-11cf-B782-00C04FD7BF43"
4435 codebase=certenr3.dll
4441 <H2>enrollment for a personal cert</H2>
4442 <BR><HR WIDTH=50%><BR><P>
4443 <FORM NAME="MSIE_Enrollment" ACTION="ms-gencert.cgi" ENCTYPE=x-www-form-
4444 encoded METHOD=POST>
4446 <TR><TD>Country</TD><TD><INPUT NAME="Country" VALUE=""></TD></TR>
4447 <TR><TD>State</TD><TD><INPUT NAME="StateOrProvince" VALUE=""></TD></TR>
4448 <TR><TD>Location</TD><TD><INPUT NAME="Location" VALUE=""></TD></TR>
4449 <TR><TD>Organization</TD><TD><INPUT NAME="Organization"
4451 <TR><TD>Organizational Unit</TD>
4452 <TD><INPUT NAME="OrganizationalUnit" VALUE=""></TD></TR>
4453 <TR><TD>Name</TD><TD><INPUT NAME="CommonName" VALUE=""></TD></TR>
4454 <TR><TD>eMail Address</TD>
4455 <TD><INPUT NAME="EmailAddress" VALUE=""></TD></TR>
4457 <TD><INPUT TYPE="BUTTON" NAME="submit" VALUE="Beantragen"></TD></TR>
4459 <INPUT TYPE="hidden" NAME="SessionId" VALUE="template_for_sessId">
4460 <INPUT TYPE="hidden" NAME="Request" VALUE="">
4462 <BR><HR WIDTH=50%><BR><P>
4465 <SCRIPT LANGUAGE=VBS>
4470 Set TheForm = Document.MSIE_Enrollment
4471 sessionId = TheForm.SessionId.value
4473 C = TheForm.Country.value
4474 SP = TheForm.StateOrProvince.value
4475 L = TheForm.Location.value
4476 O = TheForm.Organization.value
4477 OU = TheForm.OrganizationalUnit.value
4478 CN = TheForm.CommonName.value
4479 Email = TheForm.EmailAddress.value
4480 szPurpose = "ClientAuth"
4481 doAcceptanceUINow = FALSE
4486 Call Add_RDN("C", C)
4487 Call Add_RDN("S", SP)
4488 Call Add_RDN("L", L)
4489 Call Add_RDN("O", O)
4490 Call Add_RDN("OU", OU)
4491 Call Add_RDN("CN", CN)
4492 Call Add_RDN("1.2.840.113549.1.9.1", Email)
4497 On Error Resume Next
4498 sz10 = certHelper.GenerateKeyPair(sessionId, _
4499 FALSE, DN, 0, ClientAuth, FASLE, TRUE, 1)_
4500 theError = Err.Number
4502 if (sz10 = Empty OR theError <> 0) Then
4503 sz = "The error '" & Hex(theError) & "' occurred." & chr(13) & _
4504 chr(10) & "Your credentials could not be generated."
4505 result = MsgBox(sz, 0, "Credentials Enrollment")
4508 TheForm.Request.value = sz10
4513 Sub Add_RDN(sn, value)
4514 if (value <> "") then
4518 DN = DN & sn & "=" & value
4525 -----END ms-enroll.cgi-----
4527 Second, how to extract the request and feed the certificate back? We need to
4528 "normalize" the base64 encoding of the PKCS#10 format which means
4529 regenerating the lines and wrapping with BEGIN and END line. This is done by
4530 gawk. The request is taken by ca the normal way. Then the cert needs to be
4531 packed into a PKCS#7 structure (note: the use of a CRL is necessary for
4532 crl2pkcs7 as of version 0.6.6. Starting with 0.8.0 it it might probably be
4533 ommited). Finally we need to format the PKCS#7 object and generate the HTML
4534 text. I use two templates to have a clearer script.
4536 1st note: postit2 is slightly modified from a program I found at ncsa's ftp
4537 site. Grab it from http://www.easterngraphics.com/certs/IX9704/postit2.c. You
4538 need utils.c from there too.
4540 2nd note: I'm note quite sure wether the gawk script really handles all
4541 possible inputs for the request right! Today I don't use this construction
4544 3d note: the cert must be of version 3! This could be done with the nsComment
4545 line in ssleay.cnf...
4547 ------BEGIN ms-gencert.cgi-----
4549 FILE="/tmp/"`date '+%y%m%d%H%M%S'-`$$
4552 HOME=`pwd`; export HOME # as ssleay.cnf insists on having such an env var
4553 cd /usr/local/ssl #where demoCA (as named in ssleay.conf) is located
4555 postit2 -s " " -i 0x0d > "$FILE".inp # process the FORM vars
4557 SESSION_ID=`gawk '$1 == "SessionId" { print $2; exit }' "$FILE".inp`
4562 print "-----BEGIN CERTIFICATE REQUEST-----"; \
4567 if (length($2) == 72) print($2); \
4572 if (req_seen == 1) { \
4573 if (length($1) >= 72) print($1); \
4574 else if (length(lastline) < 72) { \
4576 print (lastline,$1); \
4582 print "-----END CERTIFICATE REQUEST-----"; \
4583 }' > "$FILE".pem < "$FILE".inp
4585 ssleay ca -batch -in "$FILE".pem -key passwd -out "$FILE".out
4586 ssleay crl2pkcs7 -certfile "$FILE".out -out "$FILE".pkcs7 -in demoCA/crl.pem
4588 sed s/template_for_sessId/$SESSION_ID/ <ms-enroll2a.html >"$FILE".cert
4589 /usr/local/bin/gawk \
4592 dq = sprintf("%c",34); \
4594 $0 ~ "PKCS7" { next; } \
4596 print dq$0dq" & _"; \
4597 }' <"$FILE".pkcs7 >> "$FILE".cert
4598 cat ms-enroll2b.html >>"$FILE".cert
4600 echo Content-type: text/html
4601 echo Content-length: `wc -c "$FILE".cert`
4605 -----END ms-gencert.cgi-----
4607 ----BEGIN ms-enroll2a.html----
4608 <HTML><HEAD><TITLE>Certificate Acceptance Test Page</TITLE></HEAD><BODY>
4611 classid="clsid:33BEC9E0-F78F-11cf-B782-00C04FD7BF43"
4612 codebase=certenr3.dll
4618 <H2>Your personal certificate</H2>
4619 <BR><HR WIDTH=50%><BR><P>
4621 <P><INPUT TYPE=BUTTON VALUE="Nimm mich!" NAME="InstallCert">
4623 <BR><HR WIDTH=50%><BR>
4625 <SCRIPT LANGUAGE=VBS>
4626 Sub InstallCert_OnClick
4628 sessionId = "template_for_sessId"
4629 credentials = "" & _
4630 ----END ms-enroll2a.html----
4632 ----BEGIN ms-enroll2b.html----
4634 On Error Resume Next
4635 result = certHelper.AcceptCredentials(sessionId, credentials, 0,
4637 if (IsEmpty(result)) Then
4638 sz = "The error '" & Err.Number & "' occurred." & chr(13) &
4639 chr(10) & "This Digital ID could not be registered."
4640 msgOut = MsgBox(sz, 0, "Credentials Registration Error")
4641 navigate "error.html"
4643 sz = "Digital ID successfully registered."
4644 msgOut = MsgBox(sz, 0, "Credentials Registration")
4645 navigate "success.html"
4652 ----END ms-enroll2b.html----
4654 4.) What do do with the cert?
4655 -----------------------------
4657 The cert is visible (without restarting MSIE) under the following menu:
4658 View->Options->Security->Personal certs. You can examine it's contents at
4661 To use it for client authentication you need to use SSL3.0 (fortunately
4662 SSLeay supports it with 0.8.0). Furthermore MSIE is told to only supports a
4663 kind of automatic selection of certs (I personally wasn't able to test it
4664 myself). But there is a requirement that the issuer of the server cert and
4665 the issuer of the client cert needs to be the same (according to a developer
4666 from MS). Which means: you need may more then one cert to talk to all
4669 I'm sure we will get a bit more experience after ApacheSSL is available for
4673 I hope you enjoyed reading and that in future questions on this topic will
4674 rarely appear on ssl-users@moncom.com ;-)
4676 Ilmenau, 9th of June 1997
4677 Holger Reif <reif@prakinf.tu-ilmenau.de>
4679 read you later - Holger Reif
4680 ---------------------------------------- Signaturprojekt Deutsche Einheit
4681 TU Ilmenau - Informatik - Telematik (Verdamp lang her)
4682 Holger.Reif@PrakInf.TU-Ilmenau.DE Alt wie ein Baum werden, um ueber
4683 http://Remus.PrakInf.TU-Ilmenau.DE/Reif/ alle 7 Bruecken gehen zu koennen
4686 ==== ns-ca.doc ========================================================
4688 The following documentation was supplied by Jeff Barber, who provided the
4689 patch to the CA program to add this functionality.
4693 Jeff Barber Email: jeffb@issl.atl.hp.com
4695 Hewlett Packard Phone: (404) 648-9503
4696 Internet and System Security Lab Fax: (404) 648-9516
4699 ---------------------cut /\ here for ns-ca.doc ------------------------------
4701 This document briefly describes how to use SSLeay to implement a
4702 certificate authority capable of dynamically serving up client
4703 certificates for version 3.0 beta 5 (and presumably later) versions of
4704 the Netscape Navigator. Before describing how this is done, it's
4705 important to understand a little about how the browser implements its
4706 client certificate support. This is documented in some detail in the
4707 URLs based at <URL:http://home.netscape.com/eng/security/certs.html>.
4708 Here's a brief overview:
4710 - The Navigator supports a new HTML tag "KEYGEN" which will cause
4711 the browser to generate an RSA key pair when you submit a form
4712 containing the tag. The public key, along with an optional
4713 challenge (supposedly provided for use in certificate revocation
4714 but I don't use it) is signed, DER-encoded, base-64 encoded
4715 and sent to the web server as the value of the variable
4716 whose NAME is provided in the KEYGEN tag. The private key is
4717 stored by the browser in a local key database.
4719 This "Signed Public Key And Challenge" (SPKAC) arrives formatted
4720 into 64 character lines (which are of course URL-encoded when
4721 sent via HTTP -- i.e. spaces, newlines and most punctuatation are
4722 encoded as "%HH" where HH is the hex equivalent of the ASCII code).
4723 Note that the SPKAC does not contain the other usual attributes
4724 of a certificate request, especially the subject name fields.
4725 These must be otherwise encoded in the form for submission along
4728 - Either immediately (in response to this form submission), or at
4729 some later date (a real CA will probably verify your identity in
4730 some way before issuing the certificate), a web server can send a
4731 certificate based on the public key and other attributes back to
4732 the browser by encoding it in DER (the binary form) and sending it
4733 to the browser as MIME type:
4734 "Content-type: application/x-x509-user-cert"
4736 The browser uses the public key encoded in the certificate to
4737 associate the certificate with the appropriate private key in
4738 its local key database. Now, the certificate is "installed".
4740 - When a server wants to require authentication based on client
4741 certificates, it uses the right signals via the SSL protocol to
4742 trigger the Navigator to ask you which certificate you want to
4743 send. Whether the certificate is accepted is dependent on CA
4744 certificates and so forth installed in the server and is beyond
4745 the scope of this document.
4748 Now, here's how the SSLeay package can be used to provide client
4751 - You prepare a file for input to the SSLeay ca application.
4752 The file contains a number of "name = value" pairs that identify
4753 the subject. The names here are the same subject name component
4754 identifiers used in the CA section of the lib/ssleay.conf file,
4755 such as "emailAddress", "commonName" "organizationName" and so
4756 forth. Both the long version and the short version (e.g. "Email",
4757 "CN", "O") can be used.
4759 One more name is supported: this one is "SPKAC". Its value
4760 is simply the value of the base-64 encoded SPKAC sent by the
4761 browser (with all the newlines and other space charaters
4762 removed -- and newline escapes are NOT supported).
4764 [ As of SSLeay 0.6.4, multiple lines are supported.
4765 Put a \ at the end of each line and it will be joined with the
4766 previous line with the '\n' removed - eay ]
4768 Here's a sample input file:
4772 O = Some Organization, Inc.
4773 OU = Netscape Compatibility Group
4775 Email = jxdoe@someorg.com
4776 SPKAC = MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAwmk6FMJ4uAVIYbcvIOx5+bDGTfvL8X5gE+R67ccMk6rCSGbVQz2cetyQtnI+VIs0NwdD6wjuSuVtVFbLoHonowIDAQABFgAwDQYJKoZIhvcNAQEEBQADQQBFZDUWFl6BJdomtN1Bi53mwijy1rRgJ4YirF15yBEDM3DjAQkKXHYOIX+qpz4KXKnl6EYxTnGSFL5wWt8X2iyx
4778 - You execute the ca command (either from a CGI program run out of
4779 the web server, or as a later manual task) giving it the above
4780 file as input. For example, if the file were named /tmp/cert.req,
4782 $SSLDIR/bin/ca -spkac /tmp/cert.req -out /tmp/cert
4784 The output is in DER format (binary) if a -out argument is
4785 provided, as above; otherwise, it's in the PEM format (base-64
4786 encoded DER). Also, the "-batch" switch is implied by the
4787 "-spkac" so you don't get asked whether to complete the signing
4788 (probably it shouldn't work this way but I was only interested
4789 in hacking together an online CA that could be used for issuing
4792 The "-spkac" capability doesn't support multiple files (I think).
4794 Any CHALLENGE provided in the SPKAC is simply ignored.
4796 The interactions between the identification fields you provide
4797 and those identified in your lib/ssleay.conf are the same as if
4798 you did an ordinary "ca -in infile -out outfile" -- that is, if
4799 something is marked as required in the ssleay.conf file and it
4800 isn't found in the -spkac file, the certificate won't be issued.
4802 - Now, you pick up the output from /tmp/cert and pass it back to
4803 the Navigator prepending the Content-type string described earlier.
4805 - In order to run the ca command out of a CGI program, you must
4806 provide a password to decrypt the CA's private key. You can
4807 do this by using "echo MyKeyPassword | $SSLDIR/bin/ca ..."
4808 I think there's a way to not encrypt the key file in the first
4809 place, but I didn't see how to do that, so I made a small change
4810 to the library that allows the password to be accepted from a pipe.
4811 Either way is UTTERLY INSECURE and a real CA would never do that.
4813 [ You can use the 'ssleay rsa' command to remove the password
4814 from the private key, or you can use the '-key' option to the
4815 ca command to specify the decryption key on the command line
4816 or use the -nodes option when generating the key.
4817 ca will try to clear the command line version of the password
4818 but for quite a few operating systems, this is not possible.
4821 So, what do you have to do to make use of this stuff to create an online
4822 demo CA capability with SSLeay?
4824 1 Create an HTML form for your users. The form should contain
4825 fields for all of the required or optional fields in ssleay.conf.
4826 The form must contain a KEYGEN tag somewhere with at least a NAME
4829 2 Create a CGI program to process the form input submitted by the
4830 browser. The CGI program must URL-decode the variables and create
4831 the file described above, containing subject identification info
4832 as well as the SPKAC block. It should then run the the ca program
4833 with the -spkac option. If it works (check the exit status),
4834 return the new certificate with the appropriate MIME type. If not,
4835 return the output of the ca command with MIME type "text/plain".
4837 3 Set up your web server to accept connections signed by your demo
4838 CA. This probably involves obtaining the PEM-encoded CA certificate
4839 (ordinarily in $SSLDIR/CA/cacert.pem) and installing it into a
4840 server database. See your server manual for instructions.
4843 ==== obj.doc ========================================================
4847 As part of my Crypto library, I found I required a method of identifying various
4848 objects. These objects normally had 3 different values associated with
4849 them, a short text name, a long (or lower case) text name, and an
4850 ASN.1 Object Identifier (which is a sequence of numbers).
4851 This library contains a static list of objects and functions to lookup
4852 according to one type and to return the other types.
4854 To use these routines, 'Object.h' needs to be included.
4856 For each supported object, #define entries are defined as follows
4857 #define SN_Algorithm "Algorithm"
4858 #define LN_algorithm "algorithm"
4859 #define NID_algorithm 38
4860 #define OBJ_algorithm 1L,3L,14L,3L,2L
4862 SN_ stands for short name.
4863 LN_ stands for either long name or lowercase name.
4864 NID_ stands for Numeric ID. I each object has a unique NID and this
4865 should be used internally to identify objects.
4866 OBJ_ stands for ASN.1 Object Identifier or ASN1_OBJECT as defined in the
4867 ASN1 routines. These values are used in ASN1 encoding.
4869 The following functions are to be used to return pointers into a static
4870 definition of these types. What this means is "don't try to free() any
4871 pointers returned from these functions.
4873 ASN1_OBJECT *OBJ_nid2obj(
4875 Return the ASN1_OBJECT that corresponds to a NID of n.
4879 Return the long/lower case name of the object represented by the
4884 Return the short name for the object represented by the NID of n.
4886 ASN1_OBJECT *OBJ_dup(
4888 Duplicate and return a new ASN1_OBJECT that is the same as the
4893 Given ASN1_OBJECT o, return the NID that corresponds.
4897 Given the long/lower case name 's', return the NID of the object.
4901 Given the short name 's', return the NID of the object.
4909 Since I have come across a few platforms that do not have the
4910 bsearch() function, OBJ_bsearch is my version of that function.
4911 Feel free to use this function, but you may as well just use the
4912 normal system bsearch(3) if it is present. This version also
4913 has tolerance of being passed NULL pointers.
4915 ==== keys ===========================================================
4925 valid DSA pkey types
4931 valid RSA pkey types
4935 NID_dsaWithSHA NID_dsaWithSHA DSA SHA
4936 NID_dsa NID_dsaWithSHA1 DSA SHA1
4937 NID_md2 NID_md2WithRSAEncryption RSA-pkcs1 MD2
4938 NID_md5 NID_md5WithRSAEncryption RSA-pkcs1 MD5
4939 NID_mdc2 NID_mdc2WithRSA RSA-none MDC2
4940 NID_ripemd160 NID_ripemd160WithRSA RSA-pkcs1 RIPEMD160
4941 NID_sha NID_shaWithRSAEncryption RSA-pkcs1 SHA
4942 NID_sha1 NID_sha1WithRSAEncryption RSA-pkcs1 SHA1
4944 ==== rand.doc ========================================================
4946 My Random number library.
4948 These routines can be used to generate pseudo random numbers and can be
4949 used to 'seed' the pseudo random number generator (RNG). The RNG make no
4950 effort to reproduce the same random number stream with each execution.
4951 Various other routines in the SSLeay library 'seed' the RNG when suitable
4952 'random' input data is available. Read the section at the end for details
4953 on the design of the RNG.
4958 This routine puts 'num' random bytes into 'buf'. One should make
4959 sure RAND_seed() has been called before using this routine.
4964 This routine adds more 'seed' data the RNG state. 'num' bytes
4965 are added to the RNG state, they are taken from 'buf'. This
4966 routine can be called with sensitive data such as user entered
4967 passwords. This sensitive data is in no way recoverable from
4968 the RAND library routines or state. Try to pass as much data
4969 from 'random' sources as possible into the RNG via this function.
4970 Also strongly consider using the RAND_load_file() and
4971 RAND_write_file() routines.
4973 void RAND_cleanup();
4974 When a program has finished with the RAND library, if it so
4975 desires, it can 'zero' all RNG state.
4977 The following 3 routines are convenience routines that can be used to
4978 'save' and 'restore' data from/to the RNG and it's state.
4979 Since the more 'random' data that is feed as seed data the better, why not
4980 keep it around between executions of the program? Of course the
4981 application should pass more 'random' data in via RAND_seed() and
4982 make sure no-one can read the 'random' data file.
4984 char *RAND_file_name(
4987 This routine returns a 'default' name for the location of a 'rand'
4988 file. The 'rand' file should keep a sequence of random bytes used
4989 to initialise the RNG. The filename is put in 'buf'. Buf is 'size'
4990 bytes long. Buf is returned if things go well, if they do not,
4991 NULL is returned. The 'rand' file name is generated in the
4992 following way. First, if there is a 'RANDFILE' environment
4993 variable, it is returned. Second, if there is a 'HOME' environment
4994 variable, $HOME/.rand is returned. Third, NULL is returned. NULL
4995 is also returned if a buf would overflow.
5000 This function 'adds' the 'file' into the RNG state. It does this by
5001 doing a RAND_seed() on the value returned from a stat() system call
5002 on the file and if 'number' is non-zero, upto 'number' bytes read
5003 from the file. The number of bytes passed to RAND_seed() is returned.
5005 int RAND_write_file(
5007 RAND_write_file() writes N random bytes to the file 'file', where
5008 N is the size of the internal RND state (currently 1k).
5009 This is a suitable method of saving RNG state for reloading via
5012 What follows is a description of this RNG and a description of the rational
5015 It should be noted that this RNG is intended to be used to generate
5016 'random' keys for various ciphers including generation of DH and RSA keys.
5018 It should also be noted that I have just created a system that I am happy with.
5019 It may be overkill but that does not worry me. I have not spent that much
5020 time on this algorithm so if there are glaring errors, please let me know.
5021 Speed has not been a consideration in the design of these routines.
5023 First up I will state the things I believe I need for a good RNG.
5024 1) A good hashing algorithm to mix things up and to convert the RNG 'state'
5026 2) An initial source of random 'state'.
5027 3) The state should be very large. If the RNG is being used to generate
5028 4096 bit RSA keys, 2 2048 bit random strings are required (at a minimum).
5029 If your RNG state only has 128 bits, you are obviously limiting the
5030 search space to 128 bits, not 2048. I'm probably getting a little
5031 carried away on this last point but it does indicate that it may not be
5032 a bad idea to keep quite a lot of RNG state. It should be easier to
5033 break a cipher than guess the RNG seed data.
5034 4) Any RNG seed data should influence all subsequent random numbers
5035 generated. This implies that any random seed data entered will have
5036 an influence on all subsequent random numbers generated.
5037 5) When using data to seed the RNG state, the data used should not be
5038 extractable from the RNG state. I believe this should be a
5039 requirement because one possible source of 'secret' semi random
5040 data would be a private key or a password. This data must
5041 not be disclosed by either subsequent random numbers or a
5042 'core' dump left by a program crash.
5043 6) Given the same initial 'state', 2 systems should deviate in their RNG state
5044 (and hence the random numbers generated) over time if at all possible.
5045 7) Given the random number output stream, it should not be possible to determine
5046 the RNG state or the next random number.
5049 The algorithm is as follows.
5051 There is global state made up of a 1023 byte buffer (the 'state'), a
5052 working message digest ('md') and a counter ('count').
5054 Whenever seed data is added, it is inserted into the 'state' as
5056 The input is chopped up into units of 16 bytes (or less for
5057 the last block). Each of these blocks is run through the MD5
5058 message digest. The data passed to the MD5 digest is the
5059 current 'md', the same number of bytes from the 'state'
5060 (the location determined by in incremented looping index) as
5061 the current 'block' and the new key data 'block'. The result
5062 of this is kept in 'md' and also xored into the 'state' at the
5063 same locations that were used as input into the MD5.
5064 I believe this system addresses points 1 (MD5), 3 (the 'state'),
5065 4 (via the 'md'), 5 (by the use of MD5 and xor).
5067 When bytes are extracted from the RNG, the following process is used.
5068 For each group of 8 bytes (or less), we do the following,
5069 Input into MD5, the top 8 bytes from 'md', the byte that are
5070 to be overwritten by the random bytes and bytes from the
5071 'state' (incrementing looping index). From this digest output
5072 (which is kept in 'md'), the top (upto) 8 bytes are
5073 returned to the caller and the bottom (upto) 8 bytes are xored
5075 Finally, after we have finished 'generation' random bytes for the
5076 called, 'count' (which is incremented) and 'md' are fed into MD5 and
5077 the results are kept in 'md'.
5078 I believe the above addressed points 1 (use of MD5), 6 (by
5079 hashing into the 'state' the 'old' data from the caller that
5080 is about to be overwritten) and 7 (by not using the 8 bytes
5081 given to the caller to update the 'state', but they are used
5084 So of the points raised, only 2 is not addressed, but sources of
5085 random data will always be a problem.
5088 ==== rc2.doc ========================================================
5092 RC2 is a block cipher that operates on 64bit (8 byte) quantities. It
5093 uses variable size key, but 128bit (16 byte) key would normally be considered
5094 good. It can be used in all the modes that DES can be used. This
5095 library implements the ecb, cbc, cfb64, ofb64 modes.
5097 I have implemented this library from an article posted to sci.crypt on
5098 11-Feb-1996. I personally don't know how far to trust the RC2 cipher.
5099 While it is capable of having a key of any size, not much reseach has
5100 publically been done on it at this point in time (Apr-1996)
5101 since the cipher has only been public for a few months :-)
5102 It is of a similar speed to DES and IDEA, so unless it is required for
5103 meeting some standard (SSLv2, perhaps S/MIME), it would probably be advisable
5104 to stick to IDEA, or for the paranoid, Tripple DES.
5106 Mind you, having said all that, I should mention that I just read alot and
5107 implement ciphers, I'm a 'babe in the woods' when it comes to evaluating
5110 For all calls that have an 'input' and 'output' variables, they can be the
5113 This library requires the inclusion of 'rc2.h'.
5115 All of the encryption functions take what is called an RC2_KEY as an
5116 argument. An RC2_KEY is an expanded form of the RC2 key.
5117 For all modes of the RC2 algorithm, the RC2_KEY used for
5118 decryption is the same one that was used for encryption.
5120 The define RC2_ENCRYPT is passed to specify encryption for the functions
5121 that require an encryption/decryption flag. RC2_DECRYPT is passed to
5124 Please note that any of the encryption modes specified in my DES library
5125 could be used with RC2. I have only implemented ecb, cbc, cfb64 and
5126 ofb64 for the following reasons.
5127 - ecb is the basic RC2 encryption.
5128 - cbc is the normal 'chaining' form for block ciphers.
5129 - cfb64 can be used to encrypt single characters, therefore input and output
5130 do not need to be a multiple of 8.
5131 - ofb64 is similar to cfb64 but is more like a stream cipher, not as
5132 secure (not cipher feedback) but it does not have an encrypt/decrypt mode.
5133 - If you want triple RC2, thats 384 bits of key and you must be totally
5134 obsessed with security. Still, if you want it, it is simple enough to
5135 copy the function from the DES library and change the des_encrypt to
5136 RC2_encrypt; an exercise left for the paranoid reader :-).
5138 The functions are as follows:
5145 RC2_set_key converts an 'len' byte key into a RC2_KEY.
5146 A 'ks' is an expanded form of the 'key' which is used to
5147 perform actual encryption. It can be regenerated from the RC2 key
5148 so it only needs to be kept when encryption or decryption is about
5149 to occur. Don't save or pass around RC2_KEY's since they
5150 are CPU architecture dependent, 'key's are not. RC2 is an
5151 interesting cipher in that it can be used with a variable length
5152 key. 'len' is the length of 'key' to be used as the key.
5153 A 'len' of 16 is recomended. The 'bits' argument is an
5154 interesting addition which I only found out about in Aug 96.
5155 BSAFE uses this parameter to 'limit' the number of bits used
5156 for the key. To use the 'key' unmodified, set bits to 1024.
5157 This is what old versions of my RC2 library did (SSLeay 0.6.3).
5158 RSAs BSAFE library sets this parameter to be 128 if 128 bit
5159 keys are being used. So to be compatable with BSAFE, set it
5160 to 128, if you don't want to reduce RC2's key length, leave it
5164 unsigned long *data,
5167 This is the RC2 encryption function that gets called by just about
5168 every other RC2 routine in the library. You should not use this
5169 function except to implement 'modes' of RC2. I say this because the
5170 functions that call this routine do the conversion from 'char *' to
5171 long, and this needs to be done to make sure 'non-aligned' memory
5172 access do not occur.
5173 Data is a pointer to 2 unsigned long's and key is the
5174 RC2_KEY to use. Encryption or decryption is indicated by 'encrypt'.
5175 which can have the values RC2_ENCRYPT or RC2_DECRYPT.
5177 void RC2_ecb_encrypt(
5182 This is the basic Electronic Code Book form of RC2 (in DES this
5183 mode is called Electronic Code Book so I'm going to use the term
5185 Input is encrypted into output using the key represented by
5186 key. Depending on the encrypt, encryption or
5187 decryption occurs. Input is 8 bytes long and output is 8 bytes.
5189 void RC2_cbc_encrypt(
5194 unsigned char *ivec,
5196 This routine implements RC2 in Cipher Block Chaining mode.
5197 Input, which should be a multiple of 8 bytes is encrypted
5198 (or decrypted) to output which will also be a multiple of 8 bytes.
5199 The number of bytes is in length (and from what I've said above,
5200 should be a multiple of 8). If length is not a multiple of 8, bad
5201 things will probably happen. ivec is the initialisation vector.
5202 This function updates iv after each call so that it can be passed to
5203 the next call to RC2_cbc_encrypt().
5205 void RC2_cfb64_encrypt(
5210 unsigned char *ivec,
5213 This is one of the more useful functions in this RC2 library, it
5214 implements CFB mode of RC2 with 64bit feedback.
5215 This allows you to encrypt an arbitrary number of bytes,
5216 you do not require 8 byte padding. Each call to this
5217 routine will encrypt the input bytes to output and then update ivec
5218 and num. Num contains 'how far' we are though ivec.
5219 'Encrypt' is used to indicate encryption or decryption.
5220 CFB64 mode operates by using the cipher to generate a stream
5221 of bytes which is used to encrypt the plain text.
5222 The cipher text is then encrypted to generate the next 64 bits to
5223 be xored (incrementally) with the next 64 bits of plain
5224 text. As can be seen from this, to encrypt or decrypt,
5225 the same 'cipher stream' needs to be generated but the way the next
5226 block of data is gathered for encryption is different for
5227 encryption and decryption.
5229 void RC2_ofb64_encrypt(
5234 unsigned char *ivec,
5236 This functions implements OFB mode of RC2 with 64bit feedback.
5237 This allows you to encrypt an arbitrary number of bytes,
5238 you do not require 8 byte padding. Each call to this
5239 routine will encrypt the input bytes to output and then update ivec
5240 and num. Num contains 'how far' we are though ivec.
5241 This is in effect a stream cipher, there is no encryption or
5244 For reading passwords, I suggest using des_read_pw_string() from my DES library.
5245 To generate a password from a text string, I suggest using MD5 (or MD2) to
5246 produce a 16 byte message digest that can then be passed directly to
5250 For more information about the specific RC2 modes in this library
5251 (ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the
5252 documentation on my DES library. What is said about DES is directly
5256 ==== rc4.doc ========================================================
5259 RC4 is a stream cipher that operates on a byte stream. It can be used with
5260 any length key but I would recommend normally using 16 bytes.
5262 This library requires the inclusion of 'rc4.h'.
5264 The RC4 encryption function takes what is called an RC4_KEY as an argument.
5265 The RC4_KEY is generated by the RC4_set_key function from the key bytes.
5267 RC4, being a stream cipher, does not have an encryption or decryption mode.
5268 It produces a stream of bytes that the input stream is xor'ed against and
5269 so decryption is just a case of 'encrypting' again with the same key.
5271 I have only put in one 'mode' for RC4 which is the normal one. This means
5272 there is no initialisation vector and there is no feedback of the cipher
5273 text into the cipher. This implies that you should not ever use the
5274 same key twice if you can help it. If you do, you leave yourself open to
5275 known plain text attacks; if you know the plain text and
5276 corresponding cipher text in one message, all messages that used the same
5277 key can have the cipher text decoded for the corresponding positions in the
5280 The main positive feature of RC4 is that it is a very fast cipher; about 4
5281 times faster that DES. This makes it ideally suited to protocols where the
5282 key is randomly chosen, like SSL.
5284 The functions are as follows:
5289 unsigned char *data);
5290 This function initialises the RC4_KEY structure with the key passed
5291 in 'data', which is 'len' bytes long. The key data can be any
5292 length but 16 bytes seems to be a good number.
5298 unsigned char *out);
5299 Do the actual RC4 encryption/decryption. Using the 'key', 'len'
5300 bytes are transformed from 'in' to 'out'. As mentioned above,
5301 decryption is the operation as encryption.
5303 ==== ref.doc ========================================================
5305 I have lots more references etc, and will update this list in the future,
5309 SSL The SSL Protocol - from Netscapes.
5311 RC4 Newsgroups: sci.crypt
5312 From: sterndark@netcom.com (David Sterndark)
5313 Subject: RC4 Algorithm revealed.
5314 Message-ID: <sternCvKL4B.Hyy@netcom.com>
5316 RC2 Newsgroups: sci.crypt
5317 From: pgut01@cs.auckland.ac.nz (Peter Gutmann)
5318 Subject: Specification for Ron Rivests Cipher No.2
5319 Message-ID: <4fk39f$f70@net.auckland.ac.nz>
5321 MD2 RFC1319 The MD2 Message-Digest Algorithm
5322 MD5 RFC1321 The MD5 Message-Digest Algorithm
5325 RFC1421 Privacy Enhancement for Internet Electronic Mail: Part I
5326 RFC1422 Privacy Enhancement for Internet Electronic Mail: Part II
5327 RFC1423 Privacy Enhancement for Internet Electronic Mail: Part III
5328 RFC1424 Privacy Enhancement for Internet Electronic Mail: Part IV
5330 RSA and various standard encoding
5331 PKCS#1 RSA Encryption Standard
5332 PKCS#5 Password-Based Encryption Standard
5333 PKCS#7 Cryptographic Message Syntax Standard
5334 A Layman's Guide to a Subset of ASN.1, BER, and DER
5335 An Overview of the PKCS Standards
5336 Some Examples of the PKCS Standards
5338 IDEA Chapter 3 The Block Cipher IDEA
5340 RSA, prime number generation and bignum algorithms
5341 Introduction To Algorithms,
5342 Thomas Cormen, Charles Leiserson, Ronald Rivest,
5343 Section 29 Arithmetic Circuits
5344 Section 33 Number-Theoretic Algorithms
5346 Fast Private Key algorithm
5347 Fast Decipherment Algorithm for RSA Public-Key Cryptosystem
5348 J.-J. Quisquater and C. Couvreur, Electronics Letters,
5349 14th October 1982, Vol. 18 No. 21
5351 Prime number generation and bignum algorithms.
5354 ==== rsa.doc ========================================================
5356 The RSA encryption and utility routines.
5358 The RSA routines are built on top of a big number library (the BN library).
5359 There are support routines in the X509 library for loading and manipulating
5360 the various objects in the RSA library. When errors are returned, read
5361 about the ERR library for how to access the error codes.
5363 All RSA encryption is done according to the PKCS-1 standard which is
5364 compatible with PEM and RSAref. This means that any values being encrypted
5365 must be less than the size of the modulus in bytes, minus 10, bytes long.
5367 This library uses RAND_bytes()() for it's random data, make sure to feed
5368 RAND_seed() with lots of interesting and varied data before using these
5371 The RSA library has one specific data type, the RSA structure.
5372 It is composed of 8 BIGNUM variables (see the BN library for details) and
5373 can hold either a private RSA key or a public RSA key.
5374 Some RSA libraries have different structures for public and private keys, I
5375 don't. For my libraries, a public key is determined by the fact that the
5376 RSA->d value is NULL. These routines will operate on any size RSA keys.
5377 While I'm sure 4096 bit keys are very very secure, they take a lot longer
5378 to process that 1024 bit keys :-).
5380 The function in the RSA library are as follows.
5383 This function creates a new RSA object. The sub-fields of the RSA
5384 type are also malloced so you should always use this routine to
5385 create RSA variables.
5389 This function 'frees' an RSA structure. This routine should always
5390 be used to free the RSA structure since it will also 'free' any
5391 sub-fields of the RSA type that need freeing.
5395 This function returns the size of the RSA modulus in bytes. Why do
5396 I need this you may ask, well the reason is that when you encrypt
5397 with RSA, the output string will be the size of the RSA modulus.
5398 So the output for the RSA_encrypt and the input for the RSA_decrypt
5399 routines need to be RSA_size() bytes long, because this is how many
5402 For the following 4 RSA encryption routines, it should be noted that
5403 RSA_private_decrypt() should be used on the output from
5404 RSA_public_encrypt() and RSA_public_decrypt() should be used on
5405 the output from RSA_private_encrypt().
5407 int RSA_public_encrypt(
5412 This function implements RSA public encryption, the rsa variable
5413 should be a public key (but can be a private key). 'from_len'
5414 bytes taken from 'from' and encrypted and put into 'to'. 'to' needs
5415 to be at least RSA_size(rsa) bytes long. The number of bytes
5416 written into 'to' is returned. -1 is returned on an error. The
5417 operation performed is
5418 to = from^rsa->e mod rsa->n.
5420 int RSA_private_encrypt(
5425 This function implements RSA private encryption, the rsa variable
5426 should be a private key. 'from_len' bytes taken from
5427 'from' and encrypted and put into 'to'. 'to' needs
5428 to be at least RSA_size(rsa) bytes long. The number of bytes
5429 written into 'to' is returned. -1 is returned on an error. The
5430 operation performed is
5431 to = from^rsa->d mod rsa->n.
5433 int RSA_public_decrypt(
5438 This function implements RSA public decryption, the rsa variable
5439 should be a public key (but can be a private key). 'from_len'
5440 bytes are taken from 'from' and decrypted. The decrypted data is
5441 put into 'to'. The number of bytes encrypted is returned. -1 is
5442 returned to indicate an error. The operation performed is
5443 to = from^rsa->e mod rsa->n.
5445 int RSA_private_decrypt(
5450 This function implements RSA private decryption, the rsa variable
5451 should be a private key. 'from_len' bytes are taken
5452 from 'from' and decrypted. The decrypted data is
5453 put into 'to'. The number of bytes encrypted is returned. -1 is
5454 returned to indicate an error. The operation performed is
5455 to = from^rsa->d mod rsa->n.
5461 Normally you will never use this routine.
5462 This is really an internal function which is called by
5463 RSA_private_encrypt() and RSA_private_decrypt(). It performs
5464 n=n^p mod rsa->n except that it uses the 5 extra variables in the
5465 RSA structure to make this more efficient.
5467 RSA *RSA_generate_key(
5472 This routine is used to generate RSA private keys. It takes
5473 quite a period of time to run and should only be used to
5474 generate initial private keys that should then be stored
5475 for later use. The passed callback function
5476 will be called periodically so that feedback can be given
5477 as to how this function is progressing.
5478 'bits' is the length desired for the modulus, so it would be 1024
5479 to generate a 1024 bit private key.
5480 'e' is the value to use for the public exponent 'e'. Traditionally
5481 it is set to either 3 or 0x10001.
5482 The callback function (if not NULL) is called in the following
5484 when we have generated a suspected prime number to test,
5485 callback(0,num1++,cb_arg). When it passes a prime number test,
5486 callback(1,num2++,cb_arg). When it is rejected as one of
5487 the 2 primes required due to gcd(prime,e value) != 0,
5488 callback(2,num3++,cb_arg). When finally accepted as one
5489 of the 2 primes, callback(3,num4++,cb_arg).
5492 ==== rsaref.doc ========================================================
5494 This package can be compiled to use the RSAref library.
5495 This library is not allowed outside of the USA but inside the USA it is
5496 claimed by RSA to be the only RSA public key library that can be used
5499 There are 2 files, rsaref/rsaref.c and rsaref/rsaref.h that contain the glue
5500 code to use RSAref. These files were written by looking at the PGP
5501 source code and seeing which routines it used to access RSAref.
5502 I have also been sent by some-one a copy of the RSAref header file that
5503 contains the library error codes.
5505 [ Jun 1996 update - I have recently gotten hold of RSAref 2.0 from
5506 South Africa and have been doing some performace tests. ]
5508 They have now been tested against the recently announced RSAEURO
5511 There are 2 ways to use SSLeay and RSAref. First, to build so that
5512 the programs must be linked with RSAref, add '-DRSAref' to CFLAG in the top
5513 level makefile and -lrsaref (or where ever you are keeping RSAref) to
5516 To build a makefile via util/mk1mf.pl to do this, use the 'rsaref' option.
5518 The second method is to build as per normal and link applications with
5519 the RSAglue library. The correct library order would be
5520 cc -o cmd cmd.o -lssl -lRSAglue -lcrypto -lrsaref -ldes
5521 The RSAglue library is built in the rsa directory and is NOT
5522 automatically installed.
5524 Be warned that the RSAEURO library, that is claimed to be compatible
5525 with RSAref contains a different value for the maximum number of bits
5526 supported. This changes structure sizes and so if you are using
5527 RSAEURO, change the value of RSAref_MAX_BITS in rsa/rsaref.h
5530 ==== s_mult.doc ========================================================
5532 s_mult is a test program I hacked up on a Sunday for testing non-blocking
5533 IO. It has a select loop at it's centre that handles multiple readers
5536 Try the following command
5537 ssleay s_mult -echo -nbio -ssl -v
5538 echo - sends any sent text back to the sender
5539 nbio - turns on non-blocking IO
5540 ssl - accept SSL connections, default is normal text
5544 In another window, run the following
5545 ssleay s_client -pause </etc/termcap
5547 The pause option puts in a 1 second pause in each read(2)/write(2) call
5548 so the other end will have read()s fail.
5550 ==== session.doc ========================================================
5552 I have just checked over and re-worked the session stuff.
5553 The following brief example will ignore all setup information to do with
5556 Things operate as follows.
5558 The SSL environment has a 'context', a SSL_CTX structure. This holds the
5559 cached SSL_SESSIONS (which can be reused) and the certificate lookup
5560 information. Each SSL structure needs to be associated with a SSL_CTX.
5561 Normally only one SSL_CTX structure is needed per program.
5563 SSL_CTX *SSL_CTX_new(void );
5564 void SSL_CTX_free(SSL_CTX *);
5565 These 2 functions create and destroy SSL_CTX structures
5567 The SSL_CTX has a session_cache_mode which is by default,
5568 in SSL_SESS_CACHE_SERVER mode. What this means is that the library
5569 will automatically add new session-id's to the cache upon successful
5571 If SSL_SESS_CACHE_CLIENT is set, then client certificates are also added
5573 SSL_set_session_cache_mode(ctx,mode) will set the 'mode' and
5574 SSL_get_session_cache_mode(ctx) will get the cache 'mode'.
5576 SSL_SESS_CACHE_OFF - no caching
5577 SSL_SESS_CACHE_CLIENT - only SSL_connect()
5578 SSL_SESS_CACHE_SERVER - only SSL_accept()
5579 SSL_SESS_NO_CACHE_BOTH - Either SSL_accept() or SSL_connect().
5580 If SSL_SESS_CACHE_NO_AUTO_CLEAR is set, old timed out sessions are
5581 not automatically removed each 255, SSL_connect()s or SSL_accept()s.
5583 By default, upon every 255 successful SSL_connect() or SSL_accept()s,
5584 the cache is flush. Please note that this could be expensive on
5585 a heavily loaded SSL server, in which case, turn this off and
5586 clear the cache of old entries 'manually' (with one of the functions
5587 listed below) every few hours. Perhaps I should up this number, it is hard
5588 to say. Remember, the '255' new calls is just a mechanism to get called
5589 every now and then, in theory at most 255 new session-id's will have been
5590 added but if 100 are added every minute, you would still have
5591 500 in the cache before any would start being flushed (assuming a 3 minute
5594 int SSL_CTX_sess_hits(SSL_CTX *ctx);
5595 int SSL_CTX_sess_misses(SSL_CTX *ctx);
5596 int SSL_CTX_sess_timeouts(SSL_CTX *ctx);
5597 These 3 functions return statistics about the SSL_CTX. These 3 are the
5598 number of session id reuses. hits is the number of reuses, misses are the
5599 number of lookups that failed, and timeouts is the number of cached
5600 entries ignored because they had timeouted.
5602 ctx->new_session_cb is a function pointer to a function of type
5603 int new_session_callback(SSL *ssl,SSL_SESSION *new);
5604 This function, if set in the SSL_CTX structure is called whenever a new
5605 SSL_SESSION is added to the cache. If the callback returns non-zero, it
5606 means that the application will have to do a SSL_SESSION_free()
5607 on the structure (this is
5608 to do with the cache keeping the reference counts correct, without the
5609 application needing to know about it.
5610 The 'active' parameter is the current SSL session for which this connection
5613 void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,int (*cb)());
5614 to set the callback,
5615 int (*cb)() SSL_CTX_sess_get_new_cb(SSL_CTX *ctx)
5616 to get the callback.
5618 If the 'get session' callback is set, when a session id is looked up and
5619 it is not in the session-id cache, this callback is called. The callback is
5621 SSL_SESSION *get_session_callback(unsigned char *sess_id,int sess_id_len,
5624 The get_session_callback is intended to return null if no session id is found.
5625 The reference count on the SSL_SESSION in incremented by the SSL library,
5626 if copy is 1. Otherwise, the reference count is not modified.
5628 void SSL_CTX_sess_set_get_cb(ctx,cb) sets the callback and
5629 int (*cb)()SSL_CTX_sess_get_get_cb(ctx) returns the callback.
5631 These callbacks are basically intended to be used by processes to
5632 send their session-id's to other processes. I currently have not implemented
5633 non-blocking semantics for these callbacks, it is upto the application
5634 to make the callbacks efficient if they require blocking (perhaps
5635 by 'saving' them and then 'posting them' when control returns from
5638 LHASH *SSL_CTX_sessions(SSL_CTX *ctx)
5639 This returns the session cache. The lhash strucutre can be accessed for
5640 statistics about the cache.
5642 void lh_stats(LHASH *lh, FILE *out);
5643 void lh_node_stats(LHASH *lh, FILE *out);
5644 void lh_node_usage_stats(LHASH *lh, FILE *out);
5646 can be used to print details about it's activity and current state.
5647 You can also delve directly into the lhash structure for 14 different
5648 counters that are kept against the structure. When I wrote the lhash library,
5649 I was interested in gathering statistics :-).
5650 Have a read of doc/lhash.doc in the SSLeay distribution area for more details
5651 on the lhash library.
5653 Now as mentioned ealier, when a SSL is created, it needs a SSL_CTX.
5654 SSL * SSL_new(SSL_CTX *);
5656 This stores a session. A session is secret information shared between 2
5657 SSL contexts. It will only be created if both ends of the connection have
5658 authenticated their peer to their satisfaction. It basically contains
5659 the information required to use a particular secret key cipher.
5661 To retrieve the SSL_CTX being used by a SSL,
5662 SSL_CTX *SSL_get_SSL_CTX(SSL *s);
5664 Now when a SSL session is established between to programs, the 'session'
5665 information that is cached in the SSL_CTX can me manipulated by the
5666 following functions.
5667 int SSL_set_session(SSL *s, SSL_SESSION *session);
5668 This will set the SSL_SESSION to use for the next SSL_connect(). If you use
5669 this function on an already 'open' established SSL connection, 'bad things
5670 will happen'. This function is meaning-less when used on a ssl strucutre
5671 that is just about to be used in a SSL_accept() call since the
5672 SSL_accept() will either create a new session or retrieve one from the
5675 SSL_SESSION *SSL_get_session(SSL *s);
5676 This will return the SSL_SESSION for the current SSL, NULL if there is
5677 no session associated with the SSL structure.
5679 The SSL sessions are kept in the SSL_CTX in a hash table, to remove a
5681 void SSL_CTX_remove_session(SSL_CTX *,SSL_SESSION *c);
5683 int SSL_CTX_add_session(SSL_CTX *s, SSL_SESSION *c);
5684 SSL_CTX_add_session() returns 1 if the session was already in the cache (so it
5686 Whenever a new session is created via SSL_connect()/SSL_accept(),
5687 they are automatically added to the cache, depending on the session_cache_mode
5688 settings. SSL_set_session()
5689 does not add it to the cache. Just call SSL_CTX_add_session() if you do want the
5690 session added. For a 'client' this would not normally be the case.
5691 SSL_CTX_add_session() is not normally ever used, except for doing 'evil' things
5692 which the next 2 funtions help you do.
5694 int i2d_SSL_SESSION(SSL_SESSION *in,unsigned char **pp);
5695 SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a,unsigned char **pp,long length);
5696 These 2 functions are in the standard ASN1 library form and can be used to
5697 load and save to a byte format, the SSL_SESSION structure.
5698 With these functions, you can save and read these structures to a files or
5699 arbitary byte string.
5700 The PEM_write_SSL_SESSION(fp,x) and PEM_read_SSL_SESSION(fp,x,cb) will
5701 write to a file pointer in base64 encoding.
5703 What you can do with this, is pass session information between separate
5704 processes. Please note, that you will probably also need to modify the
5705 timeout information on the SSL_SESSIONs.
5707 long SSL_get_time(SSL_SESSION *s)
5708 will return the 'time' that the session
5709 was loaded. The timeout is relative to this time. This information is
5710 saved when the SSL_SESSION is converted to binarary but it is stored
5711 in as a unix long, which is rather OS dependant, but easy to convert back.
5713 long SSL_set_time(SSL_SESSION *s,long t) will set the above mentioned time.
5714 The time value is just the value returned from time(3), and should really
5715 be defined by be to be time_t.
5717 long SSL_get_timeout(SSL_SESSION *s);
5718 long SSL_set_timeout(SSL_SESSION *s,long t);
5719 These 2 retrieve and set the timeout which is just a number of secconds
5720 from the 'SSL_get_time()' value. When this time period has elapesed,
5721 the session will no longer be in the cache (well it will actually be removed
5722 the next time it is attempted to be retrieved, so you could 'bump'
5723 the timeout so it remains valid).
5724 The 'time' and 'timeout' are set on a session when it is created, not reset
5725 each time it is reused. If you did wish to 'bump it', just after establishing
5727 SSL_set_time(ssl,time(NULL));
5730 SSL_CTX_set_timeout(SSL_CTX *ctx,unsigned long t) and
5731 SSL_CTX_get_timeout(SSL_CTX *ctx) to manipulate the default timeouts for
5732 all SSL connections created against a SSL_CTX. If you set a timeout in
5733 an SSL_CTX, all new SSL's created will inherit the timeout. It can be over
5734 written by the SSL_set_timeout(SSL *s,unsigned long t) function call.
5735 If you 'set' the timeout back to 0, the system default will be used.
5737 SSL_SESSION *SSL_SESSION_new();
5738 void SSL_SESSION_free(SSL_SESSION *ses);
5739 These 2 functions are used to create and dispose of SSL_SESSION functions.
5740 You should not ever normally need to use them unless you are using
5741 i2d_SSL_SESSION() and/or d2i_SSL_SESSION(). If you 'load' a SSL_SESSION
5742 via d2i_SSL_SESSION(), you will need to SSL_SESSION_free() it.
5743 Both SSL_set_session() and SSL_CTX_add_session() will 'take copies' of the
5744 structure (via reference counts) when it is passed to them.
5746 SSL_CTX_flush_sessions(ctx,time);
5747 The first function will clear all sessions from the cache, which have expired
5748 relative to 'time' (which could just be time(NULL)).
5750 SSL_CTX_flush_sessions(ctx,0);
5751 This is a special case that clears everything.
5753 As a final comment, a 'session' is not enough to establish a new
5754 connection. If a session has timed out, a certificate and private key
5755 need to have been associated with the SSL structure.
5756 SSL_copy_session_id(SSL *to,SSL *from); will copy not only the session
5757 strucutre but also the private key and certificate associated with
5762 So lets play at being a weird SSL server.
5764 /* setup a context */
5767 /* Lets load some session from binary into the cache, why one would do
5768 * this is not toally clear, but passing between programs does make sense
5769 * Perhaps you are using 4096 bit keys and are happy to keep them
5770 * valid for a week, to avoid the RSA overhead of 15 seconds, I'm not toally
5771 * sure, perhaps this is a process called from an SSL inetd and this is being
5772 * passed to the application. */
5773 session=d2i_SSL_SESSION(....)
5774 SSL_CTX_add_session(ctx,session);
5776 /* Lets even add a session from a file */
5777 session=PEM_read_SSL_SESSION(....)
5778 SSL_CTX_add_session(ctx,session);
5780 /* create a new SSL structure */
5783 /* At this point we want to be able to 'create' new session if
5784 * required, so we need a certificate and RSAkey. */
5785 SSL_use_RSAPrivateKey_file(ssl,...)
5786 SSL_use_certificate_file(ssl,...)
5788 /* Now since we are a server, it make little sence to load a session against
5789 * the ssl strucutre since a SSL_accept() will either create a new session or
5790 * grab an existing one from the cache. */
5792 /* grab a socket descriptor */
5795 /* associated it with the ssl strucutre */
5798 SSL_accept(ssl); /* 'do' SSL using out cert and RSA key */
5800 /* Lets print out the session details or lets save it to a file,
5801 * perhaps with a secret key cipher, so that we can pass it to the FBI
5802 * when they want to decode the session :-). While we have RSA
5803 * this does not matter much but when I do SSLv3, this will allow a mechanism
5804 * for the server/client to record the information needed to decode
5805 * the traffic that went over the wire, even when using Diffie-Hellman */
5806 PEM_write_SSL_SESSION(SSL_get_session(ssl),stdout,....)
5808 Lets 'connect' back to the caller using the same session id.
5812 SSL_set_fd(ssl2,fd2);
5813 SSL_set_session(ssl2,SSL_get_session(ssl));
5816 /* what the hell, lets accept no more connections using this session */
5817 SSL_CTX_remove_session(SSL_get_SSL_CTX(ssl),SSL_get_session(ssl));
5819 /* we could have just as easily used ssl2 since they both are using the
5821 * You will note that both ssl and ssl2 are still using the session, and
5822 * the SSL_SESSION structure will be free()ed when both ssl and ssl2
5823 * finish using the session. Also note that you could continue to initiate
5824 * connections using this session by doing SSL_get_session(ssl) to get the
5825 * existing session, but SSL_accept() will not be able to find it to
5826 * use for incoming connections.
5827 * Of corse, the session will timeout at the far end and it will no
5828 * longer be accepted after a while. The time and timeout are ignored except
5829 * by SSL_accept(). */
5831 /* Since we have had our server running for 10 weeks, and memory is getting
5832 * short, perhaps we should clear the session cache to remove those
5833 * 100000 session entries that have expired. Some may consider this
5834 * a memory leak :-) */
5836 SSL_CTX_flush_sessions(ctx,time(NULL));
5838 /* Ok, after a bit more time we wish to flush all sessions from the cache
5839 * so that all new connections will be authenticated and incure the
5840 * public key operation overhead */
5842 SSL_CTX_flush_sessions(ctx,0);
5844 /* As a final note, to copy everything to do with a SSL, use */
5845 SSL_copy_session_id(SSL *to,SSL *from);
5846 /* as this also copies the certificate and RSA key so new session can
5847 * be established using the same details */
5850 ==== sha.doc ========================================================
5852 The SHA (Secure Hash Algorithm) library.
5853 SHA is a message digest algorithm that can be used to condense an arbitrary
5854 length message down to a 20 byte hash. The functions all need to be passed
5855 a SHA_CTX which is used to hold the SHA context during multiple SHA_Update()
5856 function calls. The normal method of use for this library is as follows
5857 This library contains both SHA and SHA-1 digest algorithms. SHA-1 is
5858 an update to SHA (which should really be called SHA-0 now) which
5859 tweaks the algorithm slightly. The SHA-1 algorithm is used by simply
5860 using SHA1_Init(), SHA1_Update(), SHA1_Final() and SHA1() instead of the
5869 This library requires the inclusion of 'sha.h'.
5871 The functions are as follows:
5875 This function needs to be called to initiate a SHA_CTX structure for
5880 unsigned char *data;
5882 This updates the message digest context being generated with 'len'
5883 bytes from the 'data' pointer. The number of bytes can be any
5889 This function is called when a message digest of the data digested
5890 with SHA_Update() is wanted. The message digest is put in the 'md'
5891 array and is SHA_DIGEST_LENGTH (20) bytes long.
5897 This function performs a SHA_Init(), followed by a SHA_Update()
5898 followed by a SHA_Final() (using a local SHA_CTX).
5899 The resulting digest is put into 'md' if it is not NULL.
5900 Regardless of the value of 'md', the message
5901 digest is returned from the function. If 'md' was NULL, the message
5902 digest returned is being stored in a static structure.
5905 ==== speed.doc ========================================================
5907 To get an idea of the performance of this library, use
5910 perl util/sp-diff.pl file1 file2
5912 will print out the relative differences between the 2 files which are
5913 expected to be the output from the speed program.
5915 The performace of the library is very dependant on the Compiler
5916 quality and various flags used to build.
5920 These are some numbers I did comparing RSAref and SSLeay on a Pentium 100.
5921 [ These numbers are all out of date, as of SSL - 0.6.1 the RSA
5922 operations are about 2 times faster, so check the version number ]
5927 Pentium 100, 32meg, Windows NT Workstation 3.51
5928 linux - gcc v 2.7.0 -O3 -fomit-frame-pointer -m486
5930 Windows NT - Windows NT 3.51 - Visual C++ 4.1 - 586 code + 32bit assember
5931 Windows 3.1 - Windows NT 3.51 - Visual C++ 1.52c - 286 code + 32bit assember
5932 NT Dos Shell- Windows NT 3.51 - Visual C++ 1.52c - 286 code + 16bit assember
5934 Times are how long it takes to do an RSA private key operation.
5937 -------------------------------
5938 SSLeay NT dll 0.042s 0.202s see above
5939 SSLeay linux 0.046s 0.218s Assember inner loops (normal build)
5940 SSLeay linux 0.067s 0.380s Pure C code with BN_LLONG defined
5941 SSLeay W3.1 dll 0.108s 0.478s see above
5942 SSLeay linux 0.109s 0.713s C without BN_LLONG.
5943 RSAref2.0 linux 0.149s 0.936s
5944 SSLeay MS-DOS 0.197s 1.049s see above
5946 486DX66, 32meg, Windows NT Server 3.51
5948 -------------------------------
5949 SSLeay NT dll 0.084s 0.495s <- SSLeay 0.6.3
5950 SSLeay NT dll 0.154s 0.882s
5951 SSLeay W3.1 dll 0.335s 1.538s
5952 SSLeay MS-DOS 0.490s 2.790s
5954 What I find cute is that I'm still faster than RSAref when using standard C,
5955 without using the 'long long' data type :-), %35 faster for 512bit and we
5956 scale up to 3.2 times faster for the 'default linux' build. I should mention
5957 that people should 'try' to use either x86-lnx.s (elf), x86-lnxa.s or
5958 x86-sol.s for any x86 based unix they are building on. The only problems
5959 with be with syntax but the performance gain is quite large, especially for
5960 servers. The code is very simple, you just need to modify the 'header'.
5962 The message is, if you are stuck using RSAref, the RSA performance will be
5963 bad. Considering the code was compiled for a pentium, the 486DX66 number
5964 would indicate 'Use RSAref and turn you Pentium 100 into a 486DX66' :-).
5965 [ As of verson 0.6.1, it would be correct to say 'turn you pentium 100
5966 into a 486DX33' :-) ]
5968 I won't tell people if the DLL's are using RSAref or my stuff if no-one
5973 PS while I know I could speed things up further, I will probably not do
5974 so due to the effort involved. I did do some timings on the
5975 SSLeay bignum format -> RSAref number format conversion that occurs
5976 each time RSAref is used by SSLeay, and the numbers are trivial.
5977 0.00012s a call for 512bit vs 0.149s for the time spent in the function.
5978 0.00018s for 1024bit vs 0.938s. Insignificant.
5979 So the 'way to go', to support faster RSA libraries, if people are keen,
5980 is to write 'glue' code in a similar way that I do for RSAref and send it
5982 My base library still has the advantage of being able to operate on
5983 any size numbers, and is not that far from the performance from the
5984 leaders in the field. (-%30?)
5985 [ Well as of 0.6.1 I am now the leader in the filed on x86 (we at
5986 least very close :-) ]
5988 I suppose I should also mention some other numbers RSAref numbers, again
5991 RSAref linux 830k/s 302k/s 4390k/s
5992 SSLeay linux 855k/s 319k/s 10025k/s
5993 SSLeay NT 1158k/s 410k/s 10470k/s
5994 SSLeay w31 378k/s 143k/s 2383k/s (fully 16bit)
5996 Got to admit that Visual C++ 4.[01] is a damn fine compiler :-)
5998 Eric Young | BOOL is tri-state according to Bill Gates.
5999 AARNet: eay@cryptsoft.com | RTFM Win32 GetMessage().
6004 ==== ssl-ciph.doc ========================================================
6006 This is a quick high level summery of how things work now.
6008 Each SSLv2 and SSLv3 cipher is composed of 4 major attributes plus a few extra
6011 They are 'The key exchange algorithm', which is RSA for SSLv2 but can also
6012 be Diffle-Hellman for SSLv3.
6014 An 'Authenticion algorithm', which can be RSA, Diffle-Helman, DSS or
6021 A cipher can also be an export cipher and is either an SSLv2 or a
6024 To specify which ciphers to use, one can either specify all the ciphers,
6025 one at a time, or use 'aliases' to specify the preference and order for
6028 There are a large number of aliases, but the most importaint are
6029 kRSA, kDHr, kDHd and kEDH for key exchange types.
6031 aRSA, aDSS, aNULL and aDH for authentication
6032 DES, 3DES, RC4, RC2, IDEA and eNULL for ciphers
6033 MD5, SHA0 and SHA1 digests
6035 Now where this becomes interesting is that these can be put together to
6036 specify the order and ciphers you wish to use.
6038 To speed this up there are also aliases for certian groups of ciphers.
6040 SSLv2 - all SSLv2 ciphers
6041 SSLv3 - all SSLv3 ciphers
6042 EXP - all export ciphers
6043 LOW - all low strngth ciphers (no export ciphers, normally single DES)
6044 MEDIUM - 128 bit encryption
6047 These aliases can be joined in a : separated list which specifies to
6048 add ciphers, move them to the current location and delete them.
6050 A simpler way to look at all of this is to use the 'ssleay ciphers -v' command.
6051 The default library cipher spec is
6052 !ADH:RC4+RSA:HIGH:MEDIUM:LOW:EXP:+SSLv2:+EXP
6053 which means, first, remove from consideration any ciphers that do not
6054 authenticate. Next up, use ciphers using RC4 and RSA. Next include the HIGH,
6055 MEDIUM and the LOW security ciphers. Finish up by adding all the export
6056 ciphers on the end, then 'pull' all the SSLv2 and export ciphers to
6057 the end of the list.
6060 $ ssleay ciphers -v '!ADH:RC4+RSA:HIGH:MEDIUM:LOW:EXP:+SSLv2:+EXP'
6062 RC4-SHA SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=SHA1
6063 RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5
6064 EDH-RSA-DES-CBC3-SHA SSLv3 Kx=DH Au=RSA Enc=3DES(168) Mac=SHA1
6065 EDH-DSS-DES-CBC3-SHA SSLv3 Kx=DH Au=DSS Enc=3DES(168) Mac=SHA1
6066 DES-CBC3-SHA SSLv3 Kx=RSA Au=RSA Enc=3DES(168) Mac=SHA1
6067 IDEA-CBC-MD5 SSLv3 Kx=RSA Au=RSA Enc=IDEA(128) Mac=SHA1
6068 EDH-RSA-DES-CBC-SHA SSLv3 Kx=DH Au=RSA Enc=DES(56) Mac=SHA1
6069 EDH-DSS-DES-CBC-SHA SSLv3 Kx=DH Au=DSS Enc=DES(56) Mac=SHA1
6070 DES-CBC-SHA SSLv3 Kx=RSA Au=RSA Enc=DES(56) Mac=SHA1
6071 DES-CBC3-MD5 SSLv2 Kx=RSA Au=RSA Enc=3DES(168) Mac=MD5
6072 DES-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=DES(56) Mac=MD5
6073 IDEA-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=IDEA(128) Mac=MD5
6074 RC2-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=RC2(128) Mac=MD5
6075 RC4-MD5 SSLv2 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5
6076 EXP-EDH-RSA-DES-CBC SSLv3 Kx=DH(512) Au=RSA Enc=DES(40) Mac=SHA1 export
6077 EXP-EDH-DSS-DES-CBC-SHA SSLv3 Kx=DH(512) Au=DSS Enc=DES(40) Mac=SHA1 export
6078 EXP-DES-CBC-SHA SSLv3 Kx=RSA(512) Au=RSA Enc=DES(40) Mac=SHA1 export
6079 EXP-RC2-CBC-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export
6080 EXP-RC4-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export
6081 EXP-RC2-CBC-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export
6082 EXP-RC4-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export
6084 I would recoment people use the 'ssleay ciphers -v "text"'
6085 command to check what they are going to use.
6087 Anyway, I'm falling asleep here so I'll do some more tomorrow.
6091 ==== ssl.doc ========================================================
6093 SSL_CTX_sessions(SSL_CTX *ctx) - the session-id hash table.
6095 /* Session-id cache stats */
6097 SSL_CTX_sess_connect
6098 SSL_CTX_sess_connect_good
6100 SSL_CTX_sess_accept_good
6102 SSL_CTX_sess_cb_hits
6104 SSL_CTX_sess_timeouts
6106 /* Session-id application notification callbacks */
6107 SSL_CTX_sess_set_new_cb
6108 SSL_CTX_sess_get_new_cb
6109 SSL_CTX_sess_set_get_cb
6110 SSL_CTX_sess_get_get_cb
6112 /* Session-id cache operation mode */
6113 SSL_CTX_set_session_cache_mode
6114 SSL_CTX_get_session_cache_mode
6116 /* Set default timeout values to use. */
6120 /* Global SSL initalisation informational callback */
6121 SSL_CTX_set_info_callback
6122 SSL_CTX_get_info_callback
6123 SSL_set_info_callback
6124 SSL_get_info_callback
6126 /* If the SSL_accept/SSL_connect returned with -1, these indicate when
6127 * we should re-call *.
6132 SSL_want_x509_lookup
6134 /* Where we are in SSL initalisation, used in non-blocking, perhaps
6135 * have a look at ssl/bio_ssl.c */
6137 SSL_is_init_finished
6142 /* Used to set the 'inital' state so SSL_in_connect_init and SSL_in_accept_init
6143 * can be used to work out which function to call. */
6144 SSL_set_connect_state
6145 SSL_set_accept_state
6147 /* Where to look for certificates for authentication */
6148 SSL_set_default_verify_paths /* calles SSL_load_verify_locations */
6149 SSL_load_verify_locations
6151 /* get info from an established connection */
6162 SSL_CTX_set_cipher_list
6166 SSL_get_shared_ciphers
6189 SSL_use_RSAPrivateKey
6190 SSL_use_RSAPrivateKey_ASN1
6191 SSL_use_RSAPrivateKey_file
6193 SSL_use_PrivateKey_ASN1
6194 SSL_use_PrivateKey_file
6196 SSL_use_certificate_ASN1
6197 SSL_use_certificate_file
6199 ERR_load_SSL_strings
6200 SSL_load_error_strings
6202 /* human readable version of the 'state' of the SSL connection. */
6204 SSL_state_string_long
6205 /* These 2 report what kind of IO operation the library was trying to
6206 * perform last. Probably not very usefull. */
6208 SSL_rstate_string_long
6210 SSL_get_peer_certificate
6213 SSL_SESSION_print_fp
6226 SSL_CTX_remove_session
6227 SSL_CTX_flush_sessions
6231 /* used to hold information as to why a certificate verification failed */
6232 SSL_set_verify_result
6233 SSL_get_verify_result
6235 /* can be used by the application to associate data with an SSL structure.
6236 * It needs to be 'free()ed' by the application */
6240 /* The following all set values that are kept in the SSL_CTX but
6241 * are used as the default values when an SSL session is created.
6242 * They are over writen by the relevent SSL_xxxx functions */
6244 /* SSL_set_verify */
6245 void SSL_CTX_set_default_verify
6247 /* This callback, if set, totaly overrides the normal SSLeay verification
6248 * functions and should return 1 on success and 0 on failure */
6249 void SSL_CTX_set_cert_verify_callback
6251 /* The following are the same as the equivilent SSL_xxx functions.
6252 * Only one copy of this information is kept and if a particular
6253 * SSL structure has a local override, it is totally separate structure.
6255 int SSL_CTX_use_RSAPrivateKey
6256 int SSL_CTX_use_RSAPrivateKey_ASN1
6257 int SSL_CTX_use_RSAPrivateKey_file
6258 int SSL_CTX_use_PrivateKey
6259 int SSL_CTX_use_PrivateKey_ASN1
6260 int SSL_CTX_use_PrivateKey_file
6261 int SSL_CTX_use_certificate
6262 int SSL_CTX_use_certificate_ASN1
6263 int SSL_CTX_use_certificate_file
6266 ==== ssl_ctx.doc ========================================================
6268 This is now a bit dated, quite a few of the SSL_ functions could be
6269 SSL_CTX_ functions. I will update this in the future. 30 Aug 1996
6271 From eay@orb.mincom.oz.au Mon Dec 11 21:37:08 1995
6272 Received: by orb.mincom.oz.au id AA00696
6273 (5.65c/IDA-1.4.4 for eay); Mon, 11 Dec 1995 11:37:08 +1000
6274 Date: Mon, 11 Dec 1995 11:37:08 +1000 (EST)
6275 From: Eric Young <eay@mincom.oz.au>
6277 To: sameer <sameer@c2.org>
6278 Cc: Eric Young <eay@mincom.oz.au>
6279 Subject: Re: PEM_readX509 oesn't seem to be working
6280 In-Reply-To: <199512110102.RAA12521@infinity.c2.org>
6281 Message-Id: <Pine.SOL.3.91.951211112115.28608D-100000@orb>
6283 Content-Type: TEXT/PLAIN; charset=US-ASCII
6287 On Sun, 10 Dec 1995, sameer wrote:
6288 > OK, that's solved. I've found out that it is saying "no
6289 > certificate set" in SSL_accept because s->conn == NULL
6290 > so there is some place I need to initialize s->conn that I am
6291 > not initializing it.
6293 The full order of things for a server should be.
6297 /* The next line should not really be using ctx->cert but I'll leave it
6298 * this way right now... I don't want a X509_ routine to know about an SSL
6299 * structure, there should be an SSL_load_verify_locations... hmm, I may
6302 X509_load_verify_locations(ctx->cert,CAfile,CApath);
6304 /* Ok now for each new connection we do the following */
6307 SSL_set_verify(con,verify,verify_callback);
6309 /* set the certificate and private key to use. */
6310 SSL_use_certificate_ASN1(con,X509_certificate);
6311 SSL_use_RSAPrivateKey_ASN1(con,RSA_private_key);
6315 SSL_read(con)/SSL_write(con);
6317 There is a bit more than that but that is basically the structure.
6319 Create a context and specify where to lookup certificates.
6323 create a SSL structure
6324 set the certificate and private key
6332 Eric Young | Signature removed since it was generating
6333 AARNet: eay@mincom.oz.au | more followups than the message contents :-)
6337 ==== ssleay.doc ========================================================
6339 SSLeay: a cryptographic kitchen sink.
6342 Way back at the start of April 1995, I was looking for a mindless
6343 programming project. A friend of mine (Tim Hudson) said "why don't you do SSL,
6344 it has DES encryption in it and I would not mind using it in a SSL telnet".
6345 While it was true I had written a DES library in previous years, litle
6346 did I know what an expansive task SSL would turn into.
6348 First of all, the SSL protocol contains DES encryption. Well and good. My
6349 DES library was fast and portable. It also contained the RSA's RC4 stream
6350 cipher. Again, not a problem, some-one had just posted to sci.crypt
6351 something that was claimed to be RC4. It also contained IDEA, I had the
6352 specifications, not a problem to implement. MD5, an RFC, trivial, at most
6353 I could spend a week or so trying to see if I could speed up the
6354 implementation. All in all a nice set of ciphers.
6355 Then the first 'expantion of the scope', RSA public key
6356 encryption. Since I did not knowing a thing about public key encryption
6357 or number theory, this appeared quite a daunting task. Just writing a
6358 big number library would be problomatic in itself, let alone making it fast.
6359 At this point the scope of 'implementing SSL' expands eponentialy.
6360 First of all, the RSA private keys were being kept in ASN.1 format.
6361 Thankfully the RSA PKCS series of documents explains this format. So I now
6362 needed to be able to encode and decode arbitary ASN.1 objects. The Public
6363 keys were embeded in X509 certificates. Hmm... these are not only
6364 ASN.1 objects but they make up a heirachy of authentication. To
6365 authenticate a X509 certificate one needs to retrieve it's issuers
6366 certificate etc etc. Hmm..., so I also need to implement some kind
6367 of certificate management software. I would also have to implement
6368 software to authenticate certificates. At this point the support code made
6369 the SSL part of my library look quite small.
6370 Around this time, the first version of SSLeay was released.
6372 Ah, but here was the problem, I was not happy with the code so far. As may
6373 have become obvious, I had been treating all of this as a learning
6374 exersize, so I have completely written the library myself. As such, due
6375 to the way it had grown like a fungus, much of the library was not
6376 'elagent' or neat. There were global and static variables all over the
6377 place, the SSL part did not even handle non-blocking IO.
6378 The Great rewrite began.
6380 As of this point in time, the 'Great rewrite' has almost finished. So what
6381 follows is an approximate list of what is actually SSLeay 0.5.0
6383 /********* This needs to be updated for 0.6.0+ *************/
6386 The library contains the following routines. Please note that most of these
6387 functions are not specfic for SSL or any other particular cipher
6388 implementation. I have tried to make all the routines as general purpose
6389 as possible. So you should not think of this library as an SSL
6390 implemtation, but rather as a library of cryptographic functions
6391 that also contains SSL. I refer to each of these function groupings as
6392 libraries since they are often capable of functioning as independant
6395 First up, the general ciphers and message digests supported by the library.
6397 MD2 rfc???, a standard 'by parts' interface to this algorithm.
6398 MD5 rfc???, the same type of interface as for the MD2 library except a
6399 different algorithm.
6400 SHA THe Secure Hash Algorithm. Again the same type of interface as
6401 MD2/MD5 except the digest is 20 bytes.
6402 SHA1 The 'revised' version of SHA. Just about identical to SHA except
6403 for one tweak of an inner loop.
6404 DES This is my libdes library that has been floating around for the last
6405 few years. It has been enhanced for no other reason than completeness.
6406 It now supports ecb, cbc, cfb, ofb, cfb64, ofb64 in normal mode and
6407 triple DES modes of ecb, cbc, cfb64 and ofb64. cfb64 and ofb64 are
6408 functional interfaces to the 64 bit modes of cfb and ofb used in
6409 such a way thay they function as single character interfaces.
6410 RC4 The RSA Inc. stream cipher.
6411 RC2 The RSA Inc. block cipher.
6412 IDEA An implmentation of the IDEA cipher, the library supports ecb, cbc,
6413 cfb64 and ofb64 modes of operation.
6415 Now all the above mentioned ciphers and digests libraries support high
6416 speed, minimal 'crap in the way' type interfaces. For fastest and
6417 lowest level access, these routines should be used directly.
6419 Now there was also the matter of public key crypto systems. These are
6420 based on large integer arithmatic.
6422 BN This is my large integer library. It supports all the normal
6423 arithmentic operations. It uses malloc extensivly and as such has
6424 no limits of the size of the numbers being manipulated. If you
6425 wish to use 4000 bit RSA moduli, these routines will handle it.
6426 This library also contains routines to 'generate' prime numbers and
6427 to test for primality. The RSA and DH libraries sit on top of this
6428 library. As of this point in time, I don't support SHA, but
6429 when I do add it, it will just sit on top of the routines contained
6431 RSA This implements the RSA public key algorithm. It also contains
6432 routines that will generate a new private/public key pair.
6433 All the RSA functions conform to the PKCS#1 standard.
6434 DH This is an implementation of the
6435 Diffie-Hellman protocol. There are all the require routines for
6436 the protocol, plus extra routines that can be used to generate a
6437 strong prime for use with a specified generator. While this last
6438 routine is not generally required by applications implementing DH,
6439 It is present for completeness and because I thing it is much
6440 better to be able to 'generate' your own 'magic' numbers as oposed
6441 to using numbers suplied by others. I conform to the PKCS#3
6442 standard where required.
6444 You may have noticed the preceeding section mentions the 'generation' of
6445 prime numbers. Now this requries the use of 'random numbers'.
6447 RAND This psuedo-random number library is based on MD5 at it's core
6448 and a large internal state (2k bytes). Once you have entered enough
6449 seed data into this random number algorithm I don't feel
6450 you will ever need to worry about it generating predictable output.
6451 Due to the way I am writing a portable library, I have left the
6452 issue of how to get good initial random seed data upto the
6453 application but I do have support routines for saving and loading a
6454 persistant random number state for use between program runs.
6456 Now to make all these ciphers easier to use, a higher level
6457 interface was required. In this form, the same function would be used to
6458 encrypt 'by parts', via any one of the above mentioned ciphers.
6460 EVP The Digital EnVeloPe library is quite large. At it's core are
6461 function to perform encryption and decryption by parts while using
6462 an initial parameter to specify which of the 17 different ciphers
6463 or 4 different message digests to use. On top of these are implmented
6464 the digital signature functions, sign, verify, seal and open.
6465 Base64 encoding of binary data is also done in this library.
6467 PEM rfc???? describe the format for Privacy Enhanced eMail.
6468 As part of this standard, methods of encoding digital enveloped
6469 data is an ascii format are defined. As such, I use a form of these
6470 to encode enveloped data. While at this point in time full support
6471 for PEM has not been built into the library, a minimal subset of
6472 the secret key and Base64 encoding is present. These reoutines are
6473 mostly used to Ascii encode binary data with a 'type' associated
6474 with it and perhaps details of private key encryption used to
6477 PKCS7 This is another Digital Envelope encoding standard which uses ASN.1
6478 to encode the data. At this point in time, while there are some
6479 routines to encode and decode this binary format, full support is
6482 As Mentioned, above, there are several different ways to encode
6485 ASN1 This library is more a set of primatives used to encode the packing
6486 and unpacking of data structures. It is used by the X509
6487 certificate standard and by the PKCS standards which are used by
6488 this library. It also contains routines for duplicating and signing
6489 the structures asocisated with X509.
6491 X509 The X509 library contains routines for packing and unpacking,
6492 verifying and just about every thing else you would want to do with
6495 PKCS7 PKCS-7 is a standard for encoding digital envelope data
6496 structures. At this point in time the routines will load and save
6497 DER forms of these structees. They need to be re-worked to support
6498 the BER form which is the normal way PKCS-7 is encoded. If the
6499 previous 2 sentances don't make much sense, don't worry, this
6500 library is not used by this version of SSLeay anyway.
6502 OBJ ASN.1 uses 'object identifiers' to identify objects. A set of
6503 functions were requred to translate from ASN.1 to an intenger, to a
6504 character string. This library provieds these translations
6506 Now I mentioned an X509 library. X509 specified a hieachy of certificates
6507 which needs to be traversed to authenticate particular certificates.
6509 METH This library is used to push 'methods' of retrieving certificates
6510 into the library. There are some supplied 'methods' with SSLeay
6511 but applications can add new methods if they so desire.
6512 This library has not been finished and is not being used in this
6515 Now all the above are required for use in the initial point of this project.
6517 SSL The SSL protocol. This is a full implmentation of SSL v 2. It
6518 support both server and client authentication. SSL v 3 support
6519 will be added when the SSL v 3 specification is released in it's
6522 Now quite a few of the above mentioned libraries rely on a few 'complex'
6523 data structures. For each of these I have a library.
6525 Lhash This is a hash table library which is used extensivly.
6527 STACK An implemetation of a Stack data structure.
6529 BUF A simple character array structure that also support a function to
6530 check that the array is greater that a certain size, if it is not,
6531 it is realloced so that is it.
6533 TXT_DB A simple memory based text file data base. The application can specify
6534 unique indexes that will be enforced at update time.
6536 CONF Most of the programs written for this library require a configuration
6537 file. Instead of letting programs constantly re-implment this
6538 subsystem, the CONF library provides a consistant and flexable
6539 interface to not only configuration files but also environment
6542 But what about when something goes wrong?
6543 The one advantage (and perhaps disadvantage) of all of these
6544 functions being in one library was the ability to implement a
6545 single error reporting system.
6547 ERR This library is used to report errors. The error system records
6548 library number, function number (in the library) and reason
6549 number. Multiple errors can be reported so that an 'error' trace
6550 is created. The errors can be printed in numeric or textual form.
6553 ==== ssluse.doc ========================================================
6555 We have an SSL_CTX which contains global information for lots of
6556 SSL connections. The session-id cache and the certificate verificate cache.
6557 It also contains default values for use when certificates are used.
6563 default session-id timeout period
6564 New session-id callback
6565 Required session-id callback
6567 Informational callback
6568 Callback that is set, overrides the SSLeay X509 certificate
6570 The default Certificate/Private Key pair
6571 Default read ahead mode.
6572 Default verify mode and verify callback. These are not used
6573 if the over ride callback mentioned above is used.
6575 Each SSL can have the following defined for it before a connection is made.
6580 Certificate verify mode and callback
6581 IO object to use in the comunication.
6582 Some 'read-ahead' mode information.
6583 A previous session-id to re-use.
6585 A connection is made by using SSL_connect or SSL_accept.
6586 When non-blocking IO is being used, there are functions that can be used
6587 to determin where and why the SSL_connect or SSL_accept did not complete.
6588 This information can be used to recall the functions when the 'error'
6589 condition has dissapeared.
6591 After the connection has been made, information can be retrived about the
6592 SSL session and the session-id values that have been decided upon.
6593 The 'peer' certificate can be retrieved.
6595 The session-id values include
6601 ==== stack.doc ========================================================
6603 The stack data structure is used to store an ordered list of objects.
6604 It is basically misnamed to call it a stack but it can function that way
6605 and that is what I originally used it for. Due to the way element
6606 pointers are kept in a malloc()ed array, the most efficient way to use this
6607 structure is to add and delete elements from the end via sk_pop() and
6608 sk_push(). If you wish to do 'lookups' sk_find() is quite efficient since
6609 it will sort the stack (if required) and then do a binary search to lookup
6610 the requested item. This sorting occurs automatically so just sk_push()
6611 elements on the stack and don't worry about the order. Do remember that if
6612 you do a sk_find(), the order of the elements will change.
6614 You should never need to 'touch' this structure directly.
6615 typedef struct stack_st
6621 unsigned int num_alloc;
6625 'num' holds the number of elements in the stack, 'data' is the array of
6626 elements. 'sorted' is 1 is the list has been sorted, 0 if not.
6628 num_alloc is the number of 'nodes' allocated in 'data'. When num becomes
6629 larger than num_alloc, data is realloced to a larger size.
6630 If 'comp' is set, it is a function that is used to compare 2 of the items
6631 in the stack. The function should return -1, 0 or 1, depending on the
6634 #define sk_num(sk) ((sk)->num)
6635 #define sk_value(sk,n) ((sk)->data[n])
6637 These 2 macros should be used to access the number of elements in the
6638 'stack' and to access a pointer to one of the values.
6640 STACK *sk_new(int (*c)());
6641 This creates a new stack. If 'c', the comparison function, is not
6642 specified, the various functions that operate on a sorted 'stack' will not
6643 work (sk_find()). NULL is returned on failure.
6645 void sk_free(STACK *);
6646 This function free()'s a stack structure. The elements in the
6647 stack will not be freed so one should 'pop' and free all elements from the
6648 stack before calling this function or call sk_pop_free() instead.
6650 void sk_pop_free(STACK *st; void (*func)());
6651 This function calls 'func' for each element on the stack, passing
6652 the element as the argument. sk_free() is then called to free the 'stack'
6655 int sk_insert(STACK *sk,char *data,int where);
6656 This function inserts 'data' into stack 'sk' at location 'where'.
6657 If 'where' is larger that the number of elements in the stack, the element
6658 is put at the end. This function tends to be used by other 'stack'
6659 functions. Returns 0 on failure, otherwise the number of elements in the
6662 char *sk_delete(STACK *st,int loc);
6663 Remove the item a location 'loc' from the stack and returns it.
6664 Returns NULL if the 'loc' is out of range.
6666 char *sk_delete_ptr(STACK *st, char *p);
6667 If the data item pointed to by 'p' is in the stack, it is deleted
6668 from the stack and returned. NULL is returned if the element is not in the
6671 int sk_find(STACK *st,char *data);
6672 Returns the location that contains a value that is equal to
6673 the 'data' item. If the comparison function was not set, this function
6674 does a linear search. This function actually qsort()s the stack if it is not
6675 in order and then uses bsearch() to do the initial search. If the
6676 search fails,, -1 is returned. For mutliple items with the same
6677 value, the index of the first in the array is returned.
6679 int sk_push(STACK *st,char *data);
6680 Append 'data' to the stack. 0 is returned if there is a failure
6681 (due to a malloc failure), else 1. This is
6682 sk_insert(st,data,sk_num(st));
6684 int sk_unshift(STACK *st,char *data);
6685 Prepend 'data' to the front (location 0) of the stack. This is
6686 sk_insert(st,data,0);
6688 char *sk_shift(STACK *st);
6689 Return and delete from the stack the first element in the stack.
6690 This is sk_delete(st,0);
6692 char *sk_pop(STACK *st);
6693 Return and delete the last element on the stack. This is
6694 sk_delete(st,sk_num(sk)-1);
6696 void sk_zero(STACK *st);
6697 Removes all items from the stack. It does not 'free'
6698 pointers but is a quick way to clear a 'stack of references'.
6700 ==== threads.doc ========================================================
6702 How to compile SSLeay for multi-threading.
6704 Well basically it is quite simple, set the compiler flags and build.
6705 I have only really done much testing under Solaris and Windows NT.
6706 If you library supports localtime_r() and gmtime_r() add,
6707 -DTHREADS to the makefile parameters. You can probably survive with out
6708 this define unless you are going to have multiple threads generating
6709 certificates at once. It will not affect the SSL side of things.
6711 The approach I have taken to doing locking is to make the application provide
6712 callbacks to perform locking and so that the SSLeay library can distinguish
6713 between threads (for the error state).
6715 To have a look at an example program, 'cd mt; vi mttest.c'.
6716 To build under solaris, sh solaris.sh, for Windows NT or Windows 95,
6719 This will build mttest which will fire up 10 threads that talk SSL
6720 to each other 10 times.
6721 To enable everything to work, the application needs to call
6723 CRYPTO_set_id_callback(id_function);
6724 CRYPTO_set_locking_callback(locking_function);
6726 before any multithreading is started.
6727 id_function does not need to be defined under Windows NT or 95, the
6728 correct function will be called if it is not. Under unix, getpid()
6729 is call if the id_callback is not defined, for Solaris this is wrong
6730 (since threads id's are not pid's) but under Linux it is correct
6731 (threads are just processes sharing the data segement).
6733 The locking_callback is used to perform locking by the SSLeay library.
6736 void solaris_locking_callback(mode,type,file,line)
6742 if (mode & CRYPTO_LOCK)
6743 mutex_lock(&(lock_cs[type]));
6745 mutex_unlock(&(lock_cs[type]));
6748 Now in this case I have used mutexes instead of read/write locks, since they
6749 are faster and there are not many read locks in SSLeay, you may as well
6750 always use write locks. file and line are __FILE__ and __LINE__ from
6751 the compile and can be usefull when debugging.
6753 Now as you can see, 'type' can be one of a range of values, these values are
6754 defined in crypto/crypto.h
6755 CRYPTO_get_lock_name(type) will return a text version of what the lock is.
6756 There are CRYPTO_NUM_LOCKS locks required, so under solaris, the setup
6757 for multi-threading can be
6759 static mutex_t lock_cs[CRYPTO_NUM_LOCKS];
6765 for (i=0; i<CRYPTO_NUM_LOCKS; i++)
6766 mutex_init(&(lock_cs[i]),USYNC_THREAD,NULL);
6767 CRYPTO_set_id_callback((unsigned long (*)())solaris_thread_id);
6768 CRYPTO_set_locking_callback((void (*)())solaris_locking_callback);
6771 As a final note, under Windows NT or Windows 95, you have to be careful
6772 not to mix the various threaded, unthreaded and debug libraries.
6773 Normally if they are mixed incorrectly, mttest will crash just after printing
6774 out some usage statistics at the end. This is because the
6775 different system libraries use different malloc routines and if
6776 data is malloc()ed inside crypt32.dll or ssl32.dll and then free()ed by a
6777 different library malloc, things get very confused.
6779 The default SSLeay DLL builds use /MD, so if you use this on your
6780 application, things will work as expected. If you use /MDd,
6781 you will probably have to rebuild SSLeay using this flag.
6782 I should modify util/mk1mf.pl so it does all this correctly, but
6783 this has not been done yet.
6785 One last warning. Because locking overheads are actually quite large, the
6786 statistics collected against the SSL_CTX for successfull connections etc
6787 are not locked when updated. This does make it possible for these
6788 values to be slightly lower than they should be, if you are
6789 running multithreaded on a multi-processor box, but this does not really
6793 ==== txt_db.doc ========================================================
6795 TXT_DB, a simple text based in memory database.
6797 It holds rows of ascii data, for which the only special character is '\0'.
6798 The rows can be of an unlimited length.
6800 ==== why.doc ========================================================
6802 This file is more of a note for other people who wish to understand why
6803 the build environment is the way it is :-).
6805 The include files 'depend' as follows.
6807 crypto/*/*.c includes crypto/cryptlib.h
6808 ssl/*.c include ssl/ssl_locl.h
6809 apps/*.c include apps/apps.h
6810 crypto/cryptlib.h, ssl/ssl_locl.h and apps/apps.h
6811 all include e_os.h which contains OS/environment specific information.
6812 If you need to add something todo with a particular environment,
6813 add it to this file. It is worth remembering that quite a few libraries,
6814 like lhash, des, md, sha etc etc do not include crypto/cryptlib.h. This
6815 is because these libraries should be 'independantly compilable' and so I
6816 try to keep them this way.
6817 e_os.h is not so much a part of SSLeay, as the placing in one spot all the
6818 evil OS dependant muck.
6820 I wanted to automate as many things as possible. This includes
6821 error number generation. A
6823 will scan the source files for error codes, append them to the correct
6824 header files, and generate the functions to print the text version
6825 of the error numbers. So don't even think about adding error numbers by
6826 hand, put them in the form
6827 XXXerr(XXXX_F_XXXX,YYYY_R_YYYY);
6828 on line and it will be automatically picked up my a make errors.
6830 In a similar vein, programs to be added into ssleay in the apps directory
6831 just need to have an entry added to E_EXE in makefile.ssl and
6832 everthing will work as expected. Don't edit progs.h by hand.
6834 make links re-generates the symbolic links that are used. The reason why
6835 I keep everything in its own directory, and don't put all the
6836 test programs and header files in 'test' and 'include' is because I want
6837 to keep the 'sub-libraries' independant. I still 'pull' out
6838 indervidual libraries for use in specific projects where the code is
6839 required. I have used the 'lhash' library in just about every software
6840 project I have worked on :-).
6842 make depend generates dependancies and
6843 make dclean removes them.
6845 You will notice that I use perl quite a bit when I could be using 'sed'.
6846 The reason I decided to do this was to just stick to one 'extra' program.
6847 For Windows NT, I have perl and no sed.
6849 The util/mk1mf.pl program can be used to generate a single makefile.
6850 I use this because makefiles under Microsoft are horrific.
6851 Each C compiler seems to have different linker formats, which have
6852 to be used because the retarted C compilers explode when you do
6855 Now some would argue that I should just use the single makefile. I don't
6856 like it during develoment for 2 reasons. First, the actuall make
6857 command takes a long time. For my current setup, if I'm in
6858 crypto/bn and I type make, only the crypto/bn directory gets rebuilt,
6859 which is nice when you are modifying prototypes in bn.h which
6860 half the SSLeay depends on. The second is that to add a new souce file
6861 I just plonk it in at the required spot in the local makefile. This
6862 then alows me to keep things local, I don't need to modify a 'global'
6863 tables (the make for unix, the make for NT, the make for w31...).
6864 When I am ripping apart a library structure, it is nice to only
6865 have to worry about one directory :-).
6867 Having said all this, for the hell of it I put together 2 files that
6868 #include all the souce code (generated by doing a ls */*.o after a build).
6869 crypto.c takes only 30 seconds to build under NT and 2 minutes under linux
6870 for my pentium100. Much faster that the normal build :-).
6871 Again, the problem is that when using libraries, every program linked
6872 to libcrypto.a would suddenly get 330k of library when it may only need
6873 1k. This technique does look like a nice way to do shared libraries though.
6875 Oh yes, as a final note, to 'build' a distribution, I just type
6877 This cleans and packages everything. The directory needs to be called
6878 SSLeay since the make does a 'cd ..' and renames and tars things up.
6880 ==== req.1 ========================================================
6882 The 'req' command is used to manipulate and deal with pkcs#10
6883 certificate requests.
6885 It's default mode of operation is to load a certificate and then
6888 By default the 'req' is read from stdin in 'PEM' format.
6889 The -inform option can be used to specify 'pem' format or 'der'
6890 format. PEM format is the base64 encoding of the DER format.
6892 By default 'req' then writes the request back out. -outform can be used
6893 to indicate the desired output format, be it 'pem' or 'der'.
6895 To specify an input file, use the '-in' option and the '-out' option
6896 can be used to specify the output file.
6898 If you wish to perform a command and not output the certificate
6899 request afterwards, use the '-noout' option.
6901 When a certificate is loaded, it can be printed in a human readable
6902 ascii format via the '-text' option.
6904 To check that the signature on a certificate request is correct, use
6905 the '-verify' option to make sure that the private key contained in the
6906 certificate request corresponds to the signature.
6908 Besides the default mode, there is also the 'generate a certificate
6909 request' mode. There are several flags that trigger this mode.
6911 -new will generate a new RSA key (if required) and then prompts
6912 the user for details for the certificate request.
6913 -newkey has an argument that is the number of bits to make the new
6914 key. This function also triggers '-new'.
6916 The '-new' option can have a key to use specified instead of having to
6917 load one, '-key' is used to specify the file containg the key.
6918 -keyform can be used to specify the format of the key. Only
6919 'pem' and 'der' formats are supported, later, 'netscape' format may be added.
6921 Finally there is the '-x509' options which makes req output a self
6922 signed x509 certificate instead of a certificate request.
6924 Now as you may have noticed, there are lots of default options that
6925 cannot be specified via the command line. They are held in a 'template'
6926 or 'configuration file'. The -config option specifies which configuration
6927 file to use. See conf.doc for details on the syntax of this file.
6929 The req command uses the 'req' section of the config file.
6932 # The following variables are defined. For this example I will populate
6933 # the various values
6935 default_bits = 512 # default number of bits to use.
6936 default_keyfile = testkey.pem # Where to write the generated keyfile
6938 distinguished_name= req_dn # The section that contains the
6939 # information about which 'object' we
6940 # want to put in the DN.
6941 attributes = req_attr # The objects we want for the
6943 encrypt_rsa_key = no # Should we encrypt newly generated
6944 # keys. I strongly recommend 'yes'.
6946 # The distinguished name section. For the following entries, the
6947 # object names must exist in the SSLeay header file objects.h. If they
6948 # do not, they will be silently ignored. The entries have the following
6950 # <object_name> => string to prompt with
6951 # <object_name>_default => default value for people
6952 # <object_name>_value => Automatically use this value for this field.
6953 # <object_name>_min => minimum number of characters for data (def. 0)
6954 # <object_name>_max => maximum number of characters for data (def. inf.)
6955 # All of these entries are optional except for the first one.
6957 countryName = Country Name (2 letter code)
6958 countryName_default = AU
6960 stateOrProvinceName = State or Province Name (full name)
6961 stateOrProvinceName_default = Queensland
6963 localityName = Locality Name (eg, city)
6965 organizationName = Organization Name (eg, company)
6966 organizationName_default = Mincom Pty Ltd
6968 organizationalUnitName = Organizational Unit Name (eg, section)
6969 organizationalUnitName_default = MTR
6971 commonName = Common Name (eg, YOUR name)
6974 emailAddress = Email Address
6975 emailAddress_max = 40
6977 # The next section is the attributes section. This is exactly the
6978 # same as for the previous section except that the resulting objects are
6979 # put in the attributes field.
6981 challengePassword = A challenge password
6982 challengePassword_min = 4
6983 challengePassword_max = 20
6985 unstructuredName = An optional company name
6988 Also note that the order that attributes appear in this file is the
6989 order they will be put into the distinguished name.
6991 Once this request has been generated, it can be sent to a CA for
6995 A few quick examples....
6997 To generate a new request and a new key
7000 To generate a new request and a 1058 bit key
7003 To generate a new request using a pre-existing key
7004 req -new -key key.pem
7006 To generate a self signed x509 certificate from a certificate
7007 request using a supplied key, and we want to see the text form of the
7008 output certificate (which we will put in the file selfSign.pem
7009 req -x509 -in req.pem -key key.pem -text -out selfSign.pem
7011 Verify that the signature is correct on a certificate request.
7012 req -verify -in req.pem
7014 Verify that the signature was made using a specified public key.
7015 req -verify -in req.pem -key key.pem
7017 Print the contents of a certificate request
7018 req -text -in req.pem
7020 ==== danger ========================================================
7022 If you specify a SSLv2 cipher, and the mode is SSLv23 and the server
7023 can talk SSLv3, it will claim there is no cipher since you should be
7026 When tracing debug stuff, remember BIO_s_socket() is different to
7029 BSD/OS assember is not working
projects / openssl.git / blob