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), or
168 YYYYMMDDHHMMSSZ (the same as an ASN1 GeneralizedTime structure). In
169 both formats, seconds SS and timezone Z must be present.
171 =item B<-enddate date>
173 This allows the expiry date to be explicitly set. The format of the
174 date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure), or
175 YYYYMMDDHHMMSSZ (the same as an ASN1 GeneralizedTime structure). In
176 both formats, seconds SS and timezone Z must be present.
180 The number of days to certify the certificate for.
184 The message digest to use.
185 Any digest supported by the OpenSSL B<dgst> command can be used.
186 This option also applies to CRLs.
190 This option defines the CA "policy" to use. This is a section in
191 the configuration file which decides which fields should be mandatory
192 or match the CA certificate. Check out the B<POLICY FORMAT> section
193 for more information.
197 This is a deprecated option to make B<ca> work with very old versions of
198 the IE certificate enrollment control "certenr3". It used UniversalStrings
199 for almost everything. Since the old control has various security bugs
200 its use is strongly discouraged.
204 Normally the DN order of a certificate is the same as the order of the
205 fields in the relevant policy section. When this option is set the order
206 is the same as the request. This is largely for compatibility with the
207 older IE enrollment control which would only accept certificates if their
208 DNs match the order of the request. This is not needed for Xenroll.
212 The DN of a certificate can contain the EMAIL field if present in the
213 request DN, however it is good policy just having the e-mail set into
214 the altName extension of the certificate. When this option is set the
215 EMAIL field is removed from the certificate' subject and set only in
216 the, eventually present, extensions. The B<email_in_dn> keyword can be
217 used in the configuration file to enable this behaviour.
221 This sets the batch mode. In this mode no questions will be asked
222 and all certificates will be certified automatically.
224 =item B<-extensions section>
226 The section of the configuration file containing certificate extensions
227 to be added when a certificate is issued (defaults to B<x509_extensions>
228 unless the B<-extfile> option is used). If no extension section is
229 present then, a V1 certificate is created. If the extension section
230 is present (even if it is empty), then a V3 certificate is created. See the:w
231 L<x509v3_config(5)> manual page for details of the
232 extension section format.
234 =item B<-extfile file>
236 An additional configuration file to read certificate extensions from
237 (using the default section unless the B<-extensions> option is also
242 Specifying an engine (by its unique B<id> string) will cause B<ca>
243 to attempt to obtain a functional reference to the specified engine,
244 thus initialising it if needed. The engine will then be set as the default
245 for all available algorithms.
249 Supersedes subject name given in the request.
250 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
251 characters may be escaped by \ (backslash), no spaces are skipped.
255 This option causes field values to be interpreted as UTF8 strings, by
256 default they are interpreted as ASCII. This means that the field
257 values, whether prompted from a terminal or obtained from a
258 configuration file, must be valid UTF8 strings.
260 =item B<-create_serial>
262 If reading serial from the text file as specified in the configuration
263 fails, specifying this option creates a new random serial to be used as next
266 =item B<-multivalue-rdn>
268 This option causes the -subj argument to be interpreted with full
269 support for multivalued RDNs. Example:
271 I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
273 If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
275 =item B<-rand file...>
277 A file or files containing random data used to seed the random number
279 Multiple files can be specified separated by an OS-dependent character.
280 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
283 =item [B<-writerand file>]
285 Writes random data to the specified I<file> upon exit.
286 This can be used with a subsequent B<-rand> flag.
296 This option generates a CRL based on information in the index file.
298 =item B<-crldays num>
300 The number of days before the next CRL is due. That is the days from
301 now to place in the CRL nextUpdate field.
303 =item B<-crlhours num>
305 The number of hours before the next CRL is due.
307 =item B<-revoke filename>
309 A filename containing a certificate to revoke.
311 =item B<-valid filename>
313 A filename containing a certificate to add a Valid certificate entry.
315 =item B<-status serial>
317 Displays the revocation status of the certificate with the specified
318 serial number and exits.
322 Updates the database index to purge expired certificates.
324 =item B<-crl_reason reason>
326 Revocation reason, where B<reason> is one of: B<unspecified>, B<keyCompromise>,
327 B<CACompromise>, B<affiliationChanged>, B<superseded>, B<cessationOfOperation>,
328 B<certificateHold> or B<removeFromCRL>. The matching of B<reason> is case
329 insensitive. Setting any revocation reason will make the CRL v2.
331 In practice B<removeFromCRL> is not particularly useful because it is only used
332 in delta CRLs which are not currently implemented.
334 =item B<-crl_hold instruction>
336 This sets the CRL revocation reason code to B<certificateHold> and the hold
337 instruction to B<instruction> which must be an OID. Although any OID can be
338 used only B<holdInstructionNone> (the use of which is discouraged by RFC2459)
339 B<holdInstructionCallIssuer> or B<holdInstructionReject> will normally be used.
341 =item B<-crl_compromise time>
343 This sets the revocation reason to B<keyCompromise> and the compromise time to
344 B<time>. B<time> should be in GeneralizedTime format that is B<YYYYMMDDHHMMSSZ>.
346 =item B<-crl_CA_compromise time>
348 This is the same as B<crl_compromise> except the revocation reason is set to
351 =item B<-crlexts section>
353 The section of the configuration file containing CRL extensions to
354 include. If no CRL extension section is present then a V1 CRL is
355 created, if the CRL extension section is present (even if it is
356 empty) then a V2 CRL is created. The CRL extensions specified are
357 CRL extensions and B<not> CRL entry extensions. It should be noted
358 that some software (for example Netscape) can't handle V2 CRLs. See
359 L<x509v3_config(5)> manual page for details of the
360 extension section format.
364 =head1 CONFIGURATION FILE OPTIONS
366 The section of the configuration file containing options for B<ca>
367 is found as follows: If the B<-name> command line option is used,
368 then it names the section to be used. Otherwise the section to
369 be used must be named in the B<default_ca> option of the B<ca> section
370 of the configuration file (or in the default section of the
371 configuration file). Besides B<default_ca>, the following options are
372 read directly from the B<ca> section:
376 With the exception of B<RANDFILE>, this is probably a bug and may
377 change in future releases.
379 Many of the configuration file options are identical to command line
380 options. Where the option is present in the configuration file
381 and the command line the command line value is used. Where an
382 option is described as mandatory then it must be present in
383 the configuration file or the command line equivalent (if
390 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
391 Each line of the file should consist of the numerical form of the
392 object identifier followed by white space then the short name followed
393 by white space and finally the long name.
397 This specifies a section in the configuration file containing extra
398 object identifiers. Each line should consist of the short name of the
399 object identifier followed by B<=> and the numerical form. The short
400 and long names are the same when this option is used.
402 =item B<new_certs_dir>
404 The same as the B<-outdir> command line option. It specifies
405 the directory where new certificates will be placed. Mandatory.
409 The same as B<-cert>. It gives the file containing the CA
410 certificate. Mandatory.
414 Same as the B<-keyfile> option. The file containing the
415 CA private key. Mandatory.
419 At startup the specified file is loaded into the random number generator,
420 and at exit 256 bytes will be written to it.
422 =item B<default_days>
424 The same as the B<-days> option. The number of days to certify
427 =item B<default_startdate>
429 The same as the B<-startdate> option. The start date to certify
430 a certificate for. If not set the current time is used.
432 =item B<default_enddate>
434 The same as the B<-enddate> option. Either this option or
435 B<default_days> (or the command line equivalents) must be
438 =item B<default_crl_hours default_crl_days>
440 The same as the B<-crlhours> and the B<-crldays> options. These
441 will only be used if neither command line option is present. At
442 least one of these must be present to generate a CRL.
446 The same as the B<-md> option. Mandatory.
450 The text database file to use. Mandatory. This file must be present
451 though initially it will be empty.
453 =item B<unique_subject>
455 If the value B<yes> is given, the valid certificate entries in the
456 database must have unique subjects. if the value B<no> is given,
457 several valid certificate entries may have the exact same subject.
458 The default value is B<yes>, to be compatible with older (pre 0.9.8)
459 versions of OpenSSL. However, to make CA certificate roll-over easier,
460 it's recommended to use the value B<no>, especially if combined with
461 the B<-selfsign> command line option.
465 A text file containing the next serial number to use in hex. Mandatory.
466 This file must be present and contain a valid serial number.
470 A text file containing the next CRL number to use in hex. The crl number
471 will be inserted in the CRLs only if this file exists. If this file is
472 present, it must contain a valid CRL number.
474 =item B<x509_extensions>
476 The same as B<-extensions>.
478 =item B<crl_extensions>
480 The same as B<-crlexts>.
484 The same as B<-preserveDN>
488 The same as B<-noemailDN>. If you want the EMAIL field to be removed
489 from the DN of the certificate simply set this to 'no'. If not present
490 the default is to allow for the EMAIL filed in the certificate's DN.
494 The same as B<-msie_hack>
498 The same as B<-policy>. Mandatory. See the B<POLICY FORMAT> section
499 for more information.
501 =item B<name_opt>, B<cert_opt>
503 These options allow the format used to display the certificate details
504 when asking the user to confirm signing. All the options supported by
505 the B<x509> utilities B<-nameopt> and B<-certopt> switches can be used
506 here, except the B<no_signame> and B<no_sigdump> are permanently set
507 and cannot be disabled (this is because the certificate signature cannot
508 be displayed because the certificate has not been signed at this point).
510 For convenience the values B<ca_default> are accepted by both to produce
513 If neither option is present the format used in earlier versions of
514 OpenSSL is used. Use of the old format is B<strongly> discouraged because
515 it only displays fields mentioned in the B<policy> section, mishandles
516 multicharacter string types and does not display extensions.
518 =item B<copy_extensions>
520 Determines how extensions in certificate requests should be handled.
521 If set to B<none> or this option is not present then extensions are
522 ignored and not copied to the certificate. If set to B<copy> then any
523 extensions present in the request that are not already present are copied
524 to the certificate. If set to B<copyall> then all extensions in the
525 request are copied to the certificate: if the extension is already present
526 in the certificate it is deleted first. See the B<WARNINGS> section before
529 The main use of this option is to allow a certificate request to supply
530 values for certain extensions such as subjectAltName.
536 The policy section consists of a set of variables corresponding to
537 certificate DN fields. If the value is "match" then the field value
538 must match the same field in the CA certificate. If the value is
539 "supplied" then it must be present. If the value is "optional" then
540 it may be present. Any fields not mentioned in the policy section
541 are silently deleted, unless the B<-preserveDN> option is set but
542 this can be regarded more of a quirk than intended behaviour.
546 The input to the B<-spkac> command line option is a Netscape
547 signed public key and challenge. This will usually come from
548 the B<KEYGEN> tag in an HTML form to create a new private key.
549 It is however possible to create SPKACs using the B<spkac> utility.
551 The file should contain the variable SPKAC set to the value of
552 the SPKAC and also the required DN components as name value pairs.
553 If you need to include the same component twice then it can be
554 preceded by a number and a '.'.
556 When processing SPKAC format, the output is DER if the B<-out>
557 flag is used, but PEM format if sending to stdout or the B<-outdir>
562 Note: these examples assume that the B<ca> directory structure is
563 already set up and the relevant files already exist. This usually
564 involves creating a CA certificate and private key with B<req>, a
565 serial number file and an empty index file and placing them in
566 the relevant directories.
568 To use the sample configuration file below the directories demoCA,
569 demoCA/private and demoCA/newcerts would be created. The CA
570 certificate would be copied to demoCA/cacert.pem and its private
571 key to demoCA/private/cakey.pem. A file demoCA/serial would be
572 created containing for example "01" and the empty index file
576 Sign a certificate request:
578 openssl ca -in req.pem -out newcert.pem
580 Sign a certificate request, using CA extensions:
582 openssl ca -in req.pem -extensions v3_ca -out newcert.pem
586 openssl ca -gencrl -out crl.pem
588 Sign several requests:
590 openssl ca -infiles req1.pem req2.pem req3.pem
592 Certify a Netscape SPKAC:
594 openssl ca -spkac spkac.txt
596 A sample SPKAC file (the SPKAC line has been truncated for clarity):
598 SPKAC=MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAn7PDhCeV/xIxUg8V70YRxK2A5
600 emailAddress=steve@openssl.org
604 A sample configuration file with the relevant sections for B<ca>:
607 default_ca = CA_default # The default ca section
611 dir = ./demoCA # top dir
612 database = $dir/index.txt # index file.
613 new_certs_dir = $dir/newcerts # new certs dir
615 certificate = $dir/cacert.pem # The CA cert
616 serial = $dir/serial # serial no file
617 private_key = $dir/private/cakey.pem# CA private key
618 RANDFILE = $dir/private/.rand # random number file
620 default_days = 365 # how long to certify for
621 default_crl_days= 30 # how long before next CRL
622 default_md = md5 # md to use
624 policy = policy_any # default policy
625 email_in_dn = no # Don't add the email into cert DN
627 name_opt = ca_default # Subject name display option
628 cert_opt = ca_default # Certificate display option
629 copy_extensions = none # Don't copy extensions from request
632 countryName = supplied
633 stateOrProvinceName = optional
634 organizationName = optional
635 organizationalUnitName = optional
636 commonName = supplied
637 emailAddress = optional
641 Note: the location of all files can change either by compile time options,
642 configuration file entries, environment variables or command line options.
643 The values below reflect the default values.
645 /usr/local/ssl/lib/openssl.cnf - master configuration file
646 ./demoCA - main CA directory
647 ./demoCA/cacert.pem - CA certificate
648 ./demoCA/private/cakey.pem - CA private key
649 ./demoCA/serial - CA serial number file
650 ./demoCA/serial.old - CA serial number backup file
651 ./demoCA/index.txt - CA text database file
652 ./demoCA/index.txt.old - CA text database backup file
653 ./demoCA/certs - certificate output file
654 ./demoCA/.rnd - CA random seed information
658 The text database index file is a critical part of the process and
659 if corrupted it can be difficult to fix. It is theoretically possible
660 to rebuild the index file from all the issued certificates and a current
661 CRL: however there is no option to do this.
663 V2 CRL features like delta CRLs are not currently supported.
665 Although several requests can be input and handled at once it is only
666 possible to include one SPKAC or self-signed certificate.
670 The use of an in-memory text database can cause problems when large
671 numbers of certificates are present because, as the name implies
672 the database has to be kept in memory.
674 The B<ca> command really needs rewriting or the required functionality
675 exposed at either a command or interface level so a more friendly utility
676 (perl script or GUI) can handle things properly. The script
677 B<CA.pl> helps a little but not very much.
679 Any fields in a request that are not present in a policy are silently
680 deleted. This does not happen if the B<-preserveDN> option is used. To
681 enforce the absence of the EMAIL field within the DN, as suggested by
682 RFCs, regardless the contents of the request' subject the B<-noemailDN>
683 option can be used. The behaviour should be more friendly and
686 Canceling some commands by refusing to certify a certificate can
687 create an empty file.
691 The B<ca> command is quirky and at times downright unfriendly.
693 The B<ca> utility was originally meant as an example of how to do things
694 in a CA. It was not supposed to be used as a full blown CA itself:
695 nevertheless some people are using it for this purpose.
697 The B<ca> command is effectively a single user command: no locking is
698 done on the various files and attempts to run more than one B<ca> command
699 on the same database can have unpredictable results.
701 The B<copy_extensions> option should be used with caution. If care is
702 not taken then it can be a security risk. For example if a certificate
703 request contains a basicConstraints extension with CA:TRUE and the
704 B<copy_extensions> value is set to B<copyall> and the user does not spot
705 this when the certificate is displayed then this will hand the requester
706 a valid CA certificate.
708 This situation can be avoided by setting B<copy_extensions> to B<copy>
709 and including basicConstraints with CA:FALSE in the configuration file.
710 Then if the request contains a basicConstraints extension it will be
713 It is advisable to also include values for other extensions such
714 as B<keyUsage> to prevent a request supplying its own values.
716 Additional restrictions can be placed on the CA certificate itself.
717 For example if the CA certificate has:
719 basicConstraints = CA:TRUE, pathlen:0
721 then even if a certificate is issued with CA:TRUE it will not be valid.
725 Since OpenSSL 1.1.1, the program follows RFC5280. Specifically,
726 certificate validity period (specified by any of B<-startdate>,
727 B<-enddate> and B<-days>) will be encoded as UTCTime if the dates are
728 earlier than year 2049 (included), and as GeneralizedTime if the dates
729 are in year 2050 or later.
733 L<req(1)>, L<spkac(1)>, L<x509(1)>, L<CA.pl(1)>,
734 L<config(5)>, L<x509v3_config(5)>
738 Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved.
740 Licensed under the OpenSSL license (the "License"). You may not use
741 this file except in compliance with the License. You can obtain a copy
742 in the file LICENSE in the source distribution or at
743 L<https://www.openssl.org/source/license.html>.