5 ca - sample minimal CA application
19 [B<-crl_reason reason>]
20 [B<-crl_hold instruction>]
21 [B<-crl_compromise time>]
22 [B<-crl_CA_compromise time>]
48 [B<-extensions section>]
60 The B<ca> command is a minimal CA application. It can be used
61 to sign certificate requests in a variety of forms and generate
62 CRLs it also maintains a text database of issued certificates
65 The options descriptions will be divided into each purpose.
73 Print out a usage message.
77 This prints extra details about the operations being performed.
79 =item B<-config filename>
81 Specifies the configuration file to use.
82 Optional; for a description of the default value,
83 see L<openssl(1)/COMMAND SUMMARY>.
85 =item B<-name section>
87 Specifies the configuration file section to use (overrides
88 B<default_ca> in the B<ca> section).
92 An input filename containing a single certificate request to be
95 =item B<-ss_cert filename>
97 A single self-signed certificate to be signed by the CA.
99 =item B<-spkac filename>
101 A file containing a single Netscape signed public key and challenge
102 and additional field values to be signed by the CA. See the B<SPKAC FORMAT>
103 section for information on the required input and output format.
107 If present this should be the last option, all subsequent arguments
108 are taken as the names of files containing certificate requests.
110 =item B<-out filename>
112 The output file to output certificates to. The default is standard
113 output. The certificate details will also be printed out to this
114 file in PEM format (except that B<-spkac> outputs DER format).
116 =item B<-outdir directory>
118 The directory to output certificates to. The certificate will be
119 written to a filename consisting of the serial number in hex with
124 The CA certificate file.
126 =item B<-keyfile filename>
128 The private key to sign requests with.
130 =item B<-keyform PEM|DER>
132 The format of the data in the private key file.
135 =item B<-key password>
137 The password used to encrypt the private key. Since on some
138 systems the command line arguments are visible (e.g. Unix with
139 the 'ps' utility) this option should be used with caution.
143 Indicates the issued certificates are to be signed with the key
144 the certificate requests were signed with (given with B<-keyfile>).
145 Certificate requests signed with a different key are ignored. If
146 B<-spkac>, B<-ss_cert> or B<-gencrl> are given, B<-selfsign> is
149 A consequence of using B<-selfsign> is that the self-signed
150 certificate appears among the entries in the certificate database
151 (see the configuration option B<database>), and uses the same
152 serial number counter as all other certificates sign with the
153 self-signed certificate.
157 The key password source. For more information about the format of B<arg>
158 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
162 Don't output the text form of a certificate to the output file.
164 =item B<-startdate date>
166 This allows the start date to be explicitly set. The format of the
167 date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure).
169 =item B<-enddate date>
171 This allows the expiry date to be explicitly set. The format of the
172 date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure).
176 The number of days to certify the certificate for.
180 The message digest to use.
181 Any digest supported by the OpenSSL B<dgst> command can be used.
182 This option also applies to CRLs.
186 This option defines the CA "policy" to use. This is a section in
187 the configuration file which decides which fields should be mandatory
188 or match the CA certificate. Check out the B<POLICY FORMAT> section
189 for more information.
193 This is a deprecated option to make B<ca> work with very old versions of
194 the IE certificate enrollment control "certenr3". It used UniversalStrings
195 for almost everything. Since the old control has various security bugs
196 its use is strongly discouraged.
200 Normally the DN order of a certificate is the same as the order of the
201 fields in the relevant policy section. When this option is set the order
202 is the same as the request. This is largely for compatibility with the
203 older IE enrollment control which would only accept certificates if their
204 DNs match the order of the request. This is not needed for Xenroll.
208 The DN of a certificate can contain the EMAIL field if present in the
209 request DN, however it is good policy just having the e-mail set into
210 the altName extension of the certificate. When this option is set the
211 EMAIL field is removed from the certificate' subject and set only in
212 the, eventually present, extensions. The B<email_in_dn> keyword can be
213 used in the configuration file to enable this behaviour.
217 This sets the batch mode. In this mode no questions will be asked
218 and all certificates will be certified automatically.
220 =item B<-extensions section>
222 The section of the configuration file containing certificate extensions
223 to be added when a certificate is issued (defaults to B<x509_extensions>
224 unless the B<-extfile> option is used). If no extension section is
225 present then, a V1 certificate is created. If the extension section
226 is present (even if it is empty), then a V3 certificate is created. See the:w
227 L<x509v3_config(5)> manual page for details of the
228 extension section format.
230 =item B<-extfile file>
232 An additional configuration file to read certificate extensions from
233 (using the default section unless the B<-extensions> option is also
238 Specifying an engine (by its unique B<id> string) will cause B<ca>
239 to attempt to obtain a functional reference to the specified engine,
240 thus initialising it if needed. The engine will then be set as the default
241 for all available algorithms.
245 Supersedes subject name given in the request.
246 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
247 characters may be escaped by \ (backslash), no spaces are skipped.
251 This option causes field values to be interpreted as UTF8 strings, by
252 default they are interpreted as ASCII. This means that the field
253 values, whether prompted from a terminal or obtained from a
254 configuration file, must be valid UTF8 strings.
256 =item B<-create_serial>
258 If reading serial from the text file as specified in the configuration
259 fails, specifying this option creates a new random serial to be used as next
262 =item B<-multivalue-rdn>
264 This option causes the -subj argument to be interpreted with full
265 support for multivalued RDNs. Example:
267 I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
269 If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
271 =item B<-rand file...>
273 A file or files containing random data used to seed the random number
275 Multiple files can be specified separated by an OS-dependent character.
276 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
279 =item [B<-writerand file>]
281 Writes random data to the specified I<file> upon exit.
282 This can be used with a subsequent B<-rand> flag.
292 This option generates a CRL based on information in the index file.
294 =item B<-crldays num>
296 The number of days before the next CRL is due. That is the days from
297 now to place in the CRL nextUpdate field.
299 =item B<-crlhours num>
301 The number of hours before the next CRL is due.
303 =item B<-revoke filename>
305 A filename containing a certificate to revoke.
307 =item B<-valid filename>
309 A filename containing a certificate to add a Valid certificate entry.
311 =item B<-status serial>
313 Displays the revocation status of the certificate with the specified
314 serial number and exits.
318 Updates the database index to purge expired certificates.
320 =item B<-crl_reason reason>
322 Revocation reason, where B<reason> is one of: B<unspecified>, B<keyCompromise>,
323 B<CACompromise>, B<affiliationChanged>, B<superseded>, B<cessationOfOperation>,
324 B<certificateHold> or B<removeFromCRL>. The matching of B<reason> is case
325 insensitive. Setting any revocation reason will make the CRL v2.
327 In practice B<removeFromCRL> is not particularly useful because it is only used
328 in delta CRLs which are not currently implemented.
330 =item B<-crl_hold instruction>
332 This sets the CRL revocation reason code to B<certificateHold> and the hold
333 instruction to B<instruction> which must be an OID. Although any OID can be
334 used only B<holdInstructionNone> (the use of which is discouraged by RFC2459)
335 B<holdInstructionCallIssuer> or B<holdInstructionReject> will normally be used.
337 =item B<-crl_compromise time>
339 This sets the revocation reason to B<keyCompromise> and the compromise time to
340 B<time>. B<time> should be in GeneralizedTime format that is B<YYYYMMDDHHMMSSZ>.
342 =item B<-crl_CA_compromise time>
344 This is the same as B<crl_compromise> except the revocation reason is set to
347 =item B<-crlexts section>
349 The section of the configuration file containing CRL extensions to
350 include. If no CRL extension section is present then a V1 CRL is
351 created, if the CRL extension section is present (even if it is
352 empty) then a V2 CRL is created. The CRL extensions specified are
353 CRL extensions and B<not> CRL entry extensions. It should be noted
354 that some software (for example Netscape) can't handle V2 CRLs. See
355 L<x509v3_config(5)> manual page for details of the
356 extension section format.
360 =head1 CONFIGURATION FILE OPTIONS
362 The section of the configuration file containing options for B<ca>
363 is found as follows: If the B<-name> command line option is used,
364 then it names the section to be used. Otherwise the section to
365 be used must be named in the B<default_ca> option of the B<ca> section
366 of the configuration file (or in the default section of the
367 configuration file). Besides B<default_ca>, the following options are
368 read directly from the B<ca> section:
372 With the exception of B<RANDFILE>, this is probably a bug and may
373 change in future releases.
375 Many of the configuration file options are identical to command line
376 options. Where the option is present in the configuration file
377 and the command line the command line value is used. Where an
378 option is described as mandatory then it must be present in
379 the configuration file or the command line equivalent (if
386 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
387 Each line of the file should consist of the numerical form of the
388 object identifier followed by white space then the short name followed
389 by white space and finally the long name.
393 This specifies a section in the configuration file containing extra
394 object identifiers. Each line should consist of the short name of the
395 object identifier followed by B<=> and the numerical form. The short
396 and long names are the same when this option is used.
398 =item B<new_certs_dir>
400 The same as the B<-outdir> command line option. It specifies
401 the directory where new certificates will be placed. Mandatory.
405 The same as B<-cert>. It gives the file containing the CA
406 certificate. Mandatory.
410 Same as the B<-keyfile> option. The file containing the
411 CA private key. Mandatory.
415 At startup the specified file is loaded into the random number generator,
416 and at exit 256 bytes will be written to it.
418 =item B<default_days>
420 The same as the B<-days> option. The number of days to certify
423 =item B<default_startdate>
425 The same as the B<-startdate> option. The start date to certify
426 a certificate for. If not set the current time is used.
428 =item B<default_enddate>
430 The same as the B<-enddate> option. Either this option or
431 B<default_days> (or the command line equivalents) must be
434 =item B<default_crl_hours default_crl_days>
436 The same as the B<-crlhours> and the B<-crldays> options. These
437 will only be used if neither command line option is present. At
438 least one of these must be present to generate a CRL.
442 The same as the B<-md> option. Mandatory.
446 The text database file to use. Mandatory. This file must be present
447 though initially it will be empty.
449 =item B<unique_subject>
451 If the value B<yes> is given, the valid certificate entries in the
452 database must have unique subjects. if the value B<no> is given,
453 several valid certificate entries may have the exact same subject.
454 The default value is B<yes>, to be compatible with older (pre 0.9.8)
455 versions of OpenSSL. However, to make CA certificate roll-over easier,
456 it's recommended to use the value B<no>, especially if combined with
457 the B<-selfsign> command line option.
461 A text file containing the next serial number to use in hex. Mandatory.
462 This file must be present and contain a valid serial number.
466 A text file containing the next CRL number to use in hex. The crl number
467 will be inserted in the CRLs only if this file exists. If this file is
468 present, it must contain a valid CRL number.
470 =item B<x509_extensions>
472 The same as B<-extensions>.
474 =item B<crl_extensions>
476 The same as B<-crlexts>.
480 The same as B<-preserveDN>
484 The same as B<-noemailDN>. If you want the EMAIL field to be removed
485 from the DN of the certificate simply set this to 'no'. If not present
486 the default is to allow for the EMAIL filed in the certificate's DN.
490 The same as B<-msie_hack>
494 The same as B<-policy>. Mandatory. See the B<POLICY FORMAT> section
495 for more information.
497 =item B<name_opt>, B<cert_opt>
499 These options allow the format used to display the certificate details
500 when asking the user to confirm signing. All the options supported by
501 the B<x509> utilities B<-nameopt> and B<-certopt> switches can be used
502 here, except the B<no_signame> and B<no_sigdump> are permanently set
503 and cannot be disabled (this is because the certificate signature cannot
504 be displayed because the certificate has not been signed at this point).
506 For convenience the values B<ca_default> are accepted by both to produce
509 If neither option is present the format used in earlier versions of
510 OpenSSL is used. Use of the old format is B<strongly> discouraged because
511 it only displays fields mentioned in the B<policy> section, mishandles
512 multicharacter string types and does not display extensions.
514 =item B<copy_extensions>
516 Determines how extensions in certificate requests should be handled.
517 If set to B<none> or this option is not present then extensions are
518 ignored and not copied to the certificate. If set to B<copy> then any
519 extensions present in the request that are not already present are copied
520 to the certificate. If set to B<copyall> then all extensions in the
521 request are copied to the certificate: if the extension is already present
522 in the certificate it is deleted first. See the B<WARNINGS> section before
525 The main use of this option is to allow a certificate request to supply
526 values for certain extensions such as subjectAltName.
532 The policy section consists of a set of variables corresponding to
533 certificate DN fields. If the value is "match" then the field value
534 must match the same field in the CA certificate. If the value is
535 "supplied" then it must be present. If the value is "optional" then
536 it may be present. Any fields not mentioned in the policy section
537 are silently deleted, unless the B<-preserveDN> option is set but
538 this can be regarded more of a quirk than intended behaviour.
542 The input to the B<-spkac> command line option is a Netscape
543 signed public key and challenge. This will usually come from
544 the B<KEYGEN> tag in an HTML form to create a new private key.
545 It is however possible to create SPKACs using the B<spkac> utility.
547 The file should contain the variable SPKAC set to the value of
548 the SPKAC and also the required DN components as name value pairs.
549 If you need to include the same component twice then it can be
550 preceded by a number and a '.'.
552 When processing SPKAC format, the output is DER if the B<-out>
553 flag is used, but PEM format if sending to stdout or the B<-outdir>
558 Note: these examples assume that the B<ca> directory structure is
559 already set up and the relevant files already exist. This usually
560 involves creating a CA certificate and private key with B<req>, a
561 serial number file and an empty index file and placing them in
562 the relevant directories.
564 To use the sample configuration file below the directories demoCA,
565 demoCA/private and demoCA/newcerts would be created. The CA
566 certificate would be copied to demoCA/cacert.pem and its private
567 key to demoCA/private/cakey.pem. A file demoCA/serial would be
568 created containing for example "01" and the empty index file
572 Sign a certificate request:
574 openssl ca -in req.pem -out newcert.pem
576 Sign a certificate request, using CA extensions:
578 openssl ca -in req.pem -extensions v3_ca -out newcert.pem
582 openssl ca -gencrl -out crl.pem
584 Sign several requests:
586 openssl ca -infiles req1.pem req2.pem req3.pem
588 Certify a Netscape SPKAC:
590 openssl ca -spkac spkac.txt
592 A sample SPKAC file (the SPKAC line has been truncated for clarity):
594 SPKAC=MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAn7PDhCeV/xIxUg8V70YRxK2A5
596 emailAddress=steve@openssl.org
600 A sample configuration file with the relevant sections for B<ca>:
603 default_ca = CA_default # The default ca section
607 dir = ./demoCA # top dir
608 database = $dir/index.txt # index file.
609 new_certs_dir = $dir/newcerts # new certs dir
611 certificate = $dir/cacert.pem # The CA cert
612 serial = $dir/serial # serial no file
613 private_key = $dir/private/cakey.pem# CA private key
614 RANDFILE = $dir/private/.rand # random number file
616 default_days = 365 # how long to certify for
617 default_crl_days= 30 # how long before next CRL
618 default_md = md5 # md to use
620 policy = policy_any # default policy
621 email_in_dn = no # Don't add the email into cert DN
623 name_opt = ca_default # Subject name display option
624 cert_opt = ca_default # Certificate display option
625 copy_extensions = none # Don't copy extensions from request
628 countryName = supplied
629 stateOrProvinceName = optional
630 organizationName = optional
631 organizationalUnitName = optional
632 commonName = supplied
633 emailAddress = optional
637 Note: the location of all files can change either by compile time options,
638 configuration file entries, environment variables or command line options.
639 The values below reflect the default values.
641 /usr/local/ssl/lib/openssl.cnf - master configuration file
642 ./demoCA - main CA directory
643 ./demoCA/cacert.pem - CA certificate
644 ./demoCA/private/cakey.pem - CA private key
645 ./demoCA/serial - CA serial number file
646 ./demoCA/serial.old - CA serial number backup file
647 ./demoCA/index.txt - CA text database file
648 ./demoCA/index.txt.old - CA text database backup file
649 ./demoCA/certs - certificate output file
650 ./demoCA/.rnd - CA random seed information
654 The text database index file is a critical part of the process and
655 if corrupted it can be difficult to fix. It is theoretically possible
656 to rebuild the index file from all the issued certificates and a current
657 CRL: however there is no option to do this.
659 V2 CRL features like delta CRLs are not currently supported.
661 Although several requests can be input and handled at once it is only
662 possible to include one SPKAC or self-signed certificate.
666 The use of an in-memory text database can cause problems when large
667 numbers of certificates are present because, as the name implies
668 the database has to be kept in memory.
670 The B<ca> command really needs rewriting or the required functionality
671 exposed at either a command or interface level so a more friendly utility
672 (perl script or GUI) can handle things properly. The script
673 B<CA.pl> helps a little but not very much.
675 Any fields in a request that are not present in a policy are silently
676 deleted. This does not happen if the B<-preserveDN> option is used. To
677 enforce the absence of the EMAIL field within the DN, as suggested by
678 RFCs, regardless the contents of the request' subject the B<-noemailDN>
679 option can be used. The behaviour should be more friendly and
682 Canceling some commands by refusing to certify a certificate can
683 create an empty file.
687 The B<ca> command is quirky and at times downright unfriendly.
689 The B<ca> utility was originally meant as an example of how to do things
690 in a CA. It was not supposed to be used as a full blown CA itself:
691 nevertheless some people are using it for this purpose.
693 The B<ca> command is effectively a single user command: no locking is
694 done on the various files and attempts to run more than one B<ca> command
695 on the same database can have unpredictable results.
697 The B<copy_extensions> option should be used with caution. If care is
698 not taken then it can be a security risk. For example if a certificate
699 request contains a basicConstraints extension with CA:TRUE and the
700 B<copy_extensions> value is set to B<copyall> and the user does not spot
701 this when the certificate is displayed then this will hand the requester
702 a valid CA certificate.
704 This situation can be avoided by setting B<copy_extensions> to B<copy>
705 and including basicConstraints with CA:FALSE in the configuration file.
706 Then if the request contains a basicConstraints extension it will be
709 It is advisable to also include values for other extensions such
710 as B<keyUsage> to prevent a request supplying its own values.
712 Additional restrictions can be placed on the CA certificate itself.
713 For example if the CA certificate has:
715 basicConstraints = CA:TRUE, pathlen:0
717 then even if a certificate is issued with CA:TRUE it will not be valid.
721 L<req(1)>, L<spkac(1)>, L<x509(1)>, L<CA.pl(1)>,
722 L<config(5)>, L<x509v3_config(5)>
726 Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.
728 Licensed under the OpenSSL license (the "License"). You may not use
729 this file except in compliance with the License. You can obtain a copy
730 in the file LICENSE in the source distribution or at
731 L<https://www.openssl.org/source/license.html>.