2 {- OpenSSL::safe::output_do_not_edit_headers(); -}
6 openssl-x509 - Certificate display and signing command
12 [B<-inform> B<DER>|B<PEM>]
13 [B<-outform> B<DER>|B<PEM>]
14 [B<-keyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>]
15 [B<-CAform> B<DER>|B<PEM>|B<P12>]
16 [B<-CAkeyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>]
22 [B<-subject_hash_old>]
44 [B<-addreject> I<arg>]
54 [B<-CAkey> I<filename>]
56 [B<-CAserial> I<filename>]
60 [B<-force_pubkey> I<filename>]
63 [B<-ext> I<extensions>]
64 [B<-certopt> I<option>]
65 [B<-checkhost> I<host>]
66 [B<-checkemail> I<host>]
67 [B<-checkip> I<ipaddr>]
71 [B<-extfile> I<filename>]
72 [B<-extensions> I<section>]
73 [B<-sigopt> I<nm>:I<v>]
74 [B<-vfyopt> I<nm>:I<v>]
76 {- $OpenSSL::safe::opt_name_synopsis -}
77 {- $OpenSSL::safe::opt_r_synopsis -}
78 {- $OpenSSL::safe::opt_engine_synopsis -}
79 {- $OpenSSL::safe::opt_provider_synopsis -}
81 =for openssl ifdef engine subject_hash_old issuer_hash_old
85 This command is a multi-purposes certificate command. It can
86 be used to display certificate information, convert certificates to
87 various forms, sign certificate requests like a "mini CA" or edit
88 certificate trust settings.
90 Since there are a large number of options they will split up into
95 =head2 Input, Output, and General Purpose Options
101 Print out a usage message.
103 =item B<-inform> B<DER>|B<PEM>
105 The CSR input format; the default is B<PEM>.
106 See L<openssl(1)/Format Options> for details.
108 The input is normally an X.509 certificate file of any format,
109 but this can change if other options such as B<-req> are used.
111 B<-outform> B<DER>|B<PEM>
113 The output format; the default is B<PEM>.
114 See L<openssl(1)/Format Options> for details.
116 =item B<-in> I<filename>
118 This specifies the input filename to read a certificate from or standard input
119 if this option is not specified.
121 =item B<-out> I<filename>
123 This specifies the output filename to write to or standard output by
129 This affects any signing or display option that uses a message
130 digest, such as the B<-fingerprint>, B<-signkey> and B<-CA> options.
131 Any digest supported by the L<openssl-dgst(1)> command can be used.
132 If not specified then SHA1 is used with B<-fingerprint> or
133 the default digest for the signing algorithm is used, typically SHA256.
135 =item B<-preserve_dates>
137 When signing a certificate, preserve the "notBefore" and "notAfter" dates
138 instead of adjusting them to current time and duration.
139 Cannot be used with the B<-days> option.
141 {- $OpenSSL::safe::opt_r_synopsis -}
143 {- $OpenSSL::safe::opt_engine_item -}
145 {- $OpenSSL::safe::opt_provider_item -}
149 =head2 Display Options
151 Note: the B<-alias> and B<-purpose> options are also display options
152 but are described in the L</Trust Settings> section.
158 Prints out the certificate in text form. Full details are output including the
159 public key, signature algorithms, issuer and subject names, serial number
160 any extensions present and any trust settings.
162 =item B<-ext> I<extensions>
164 Prints out the certificate extensions in text form. Extensions are specified
165 with a comma separated string, e.g., "subjectAltName,subjectKeyIdentifier".
166 See the L<x509v3_config(5)> manual page for the extension names.
168 =item B<-certopt> I<option>
170 Customise the output format used with B<-text>. The I<option> argument
171 can be a single option or multiple options separated by commas. The
172 B<-certopt> switch may be also be used more than once to set multiple
173 options. See the L</Text Options> section for more information.
175 =item B<-checkhost> I<host>
177 Check that the certificate matches the specified host.
179 =item B<-checkemail> I<email>
181 Check that the certificate matches the specified email address.
183 =item B<-checkip> I<ipaddr>
185 Check that the certificate matches the specified IP address.
189 This option prevents output of the encoded version of the certificate.
193 Outputs the certificate's SubjectPublicKeyInfo block in PEM format.
197 This option prints out the value of the modulus of the public key
198 contained in the certificate.
202 Outputs the certificate serial number.
204 =item B<-subject_hash>
206 Outputs the "hash" of the certificate subject name. This is used in OpenSSL to
207 form an index to allow certificates in a directory to be looked up by subject
210 =item B<-issuer_hash>
212 Outputs the "hash" of the certificate issuer name.
216 Outputs the OCSP hash values for the subject name and public key.
220 Synonym for "-subject_hash" for backward compatibility reasons.
222 =item B<-subject_hash_old>
224 Outputs the "hash" of the certificate subject name using the older algorithm
225 as used by OpenSSL before version 1.0.0.
227 =item B<-issuer_hash_old>
229 Outputs the "hash" of the certificate issuer name using the older algorithm
230 as used by OpenSSL before version 1.0.0.
234 Outputs the subject name.
238 Outputs the issuer name.
240 {- $OpenSSL::safe::opt_name_item -}
244 Outputs the email address(es) if any.
248 Outputs the OCSP responder address(es) if any.
252 Prints out the start date of the certificate, that is the notBefore date.
256 Prints out the expiry date of the certificate, that is the notAfter date.
260 Prints out the start and expiry dates of a certificate.
262 =item B<-checkend> I<arg>
264 Checks if the certificate expires within the next I<arg> seconds and exits
265 nonzero if yes it will expire or zero if not.
267 =item B<-fingerprint>
269 Calculates and outputs the digest of the DER encoded version of the entire
270 certificate (see digest options).
271 This is commonly called a "fingerprint". Because of the nature of message
272 digests, the fingerprint of a certificate is unique to that certificate and
273 two certificates with the same fingerprint can be considered to be the same.
277 This outputs the certificate in the form of a C source file.
281 =head2 Trust Settings
283 A B<trusted certificate> is an ordinary certificate which has several
284 additional pieces of information attached to it such as the permitted
285 and prohibited uses of the certificate and an "alias".
287 Normally when a certificate is being verified at least one certificate
288 must be "trusted". By default a trusted certificate must be stored
289 locally and must be a root CA: any certificate chain ending in this CA
290 is then usable for any purpose.
292 Trust settings currently are only used with a root CA. They allow a finer
293 control over the purposes the root CA can be used for. For example a CA
294 may be trusted for SSL client but not SSL server use.
296 See the description in L<openssl-verify(1)> for more information
297 on the meaning of trust settings.
299 Future versions of OpenSSL will recognize trust settings on any
300 certificate: not just root CAs.
307 Output a B<trusted> certificate rather than an ordinary. An ordinary
308 or trusted certificate can be input but by default an ordinary
309 certificate is output and any trust settings are discarded. With the
310 B<-trustout> option a trusted certificate is output. A trusted
311 certificate is automatically output if any trust settings are modified.
313 =item B<-setalias> I<arg>
315 Sets the alias of the certificate. This will allow the certificate
316 to be referred to using a nickname for example "Steve's Certificate".
320 Outputs the certificate alias, if any.
324 Clears all the permitted or trusted uses of the certificate.
328 Clears all the prohibited or rejected uses of the certificate.
330 =item B<-addtrust> I<arg>
332 Adds a trusted certificate use.
333 Any object name can be used here but currently only B<clientAuth> (SSL client
334 use), B<serverAuth> (SSL server use), B<emailProtection> (S/MIME email) and
335 B<anyExtendedKeyUsage> are used.
336 As of OpenSSL 1.1.0, the last of these blocks all purposes when rejected or
337 enables all purposes when trusted.
338 Other OpenSSL applications may define additional uses.
340 =item B<-addreject> I<arg>
342 Adds a prohibited use. It accepts the same values as the B<-addtrust>
347 This option performs tests on the certificate extensions and outputs
348 the results. For a more complete description see the
349 L</CERTIFICATE EXTENSIONS> section.
353 =head2 Signing Options
355 This command can be used to sign certificates and requests: it
356 can thus behave like a "mini CA".
360 =item B<-signkey> I<arg>
362 This option causes the input file to be self signed using the supplied
363 private key or engine.
365 It sets the issuer name to the subject name (i.e., makes it self-issued)
366 and changes the public key to the supplied value (unless overridden by
367 B<-force_pubkey>). It sets the validity start date to the current time
368 and the end date to a value determined by the B<-days> option.
369 It retains any certificate extensions unless the B<-clrext> option is supplied;
370 this includes, for example, any existing key identifier extensions.
374 Corrupt the signature before writing it; this can be useful
377 =item B<-sigopt> I<nm>:I<v>
379 Pass options to the signature algorithm during sign operations.
380 Names and values of these options are algorithm-specific.
382 =item B<-vfyopt> I<nm>:I<v>
384 Pass options to the signature algorithm during verify operations.
385 Names and values of these options are algorithm-specific.
387 =item B<-passin> I<arg>
389 The key password source. For more information about the format of I<arg>
390 see L<openssl(1)/Pass Phrase Options>.
394 Delete any extensions from a certificate. This option is used when a
395 certificate is being created from another certificate (for example with
396 the B<-signkey> or the B<-CA> options). Normally all extensions are
399 =item B<-keyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>
401 The key format; the default is B<PEM>.
402 The only value with effect is B<ENGINE>; all others have become obsolete.
403 See L<openssl(1)/Format Options> for details.
405 =item B<-CAform> B<DER>|B<PEM>|B<P12>,
407 The format for the CA certificate.
408 This option has no effect and is retained for backward compatibility.
410 =item B<-CAkeyform> B<DER>|B<PEM>|B<P12>|B<ENGINE>
412 The format for the CA key; the default is B<PEM>.
413 The only value with effect is B<ENGINE>; all others have become obsolete.
414 See L<openssl(1)/Format Options> for details.
416 =item B<-days> I<arg>
418 Specifies the number of days to make a certificate valid for. The default
419 is 30 days. Cannot be used with the B<-preserve_dates> option.
423 Converts a certificate into a certificate request. The B<-signkey> option
424 is used to pass the required private key.
428 By default a certificate is expected on input. With this option a
429 certificate request is expected instead.
431 =item B<-set_serial> I<n>
433 Specifies the serial number to use. This option can be used with either
434 the B<-signkey> or B<-CA> options. If used in conjunction with the B<-CA>
435 option the serial number file (as specified by the B<-CAserial> or
436 B<-CAcreateserial> options) is not used.
438 The serial number can be decimal or hex (if preceded by C<0x>).
440 =item B<-CA> I<filename>
442 Specifies the CA certificate to be used for signing. When this option is
443 present, this command behaves like a "mini CA". The input file is signed by
444 this CA using this option: that is its issuer name is set to the subject name
445 of the CA and it is digitally signed using the CAs private key.
447 This option is normally combined with the B<-req> option. Without the
448 B<-req> option the input is a certificate which must be self signed.
450 =item B<-CAkey> I<filename>
452 Sets the CA private key to sign a certificate with. If this option is
453 not specified then it is assumed that the CA private key is present in
454 the CA certificate file.
456 =item B<-CAserial> I<filename>
458 Sets the CA serial number file to use.
460 When the B<-CA> option is used to sign a certificate it uses a serial
461 number specified in a file. This file consists of one line containing
462 an even number of hex digits with the serial number to use. After each
463 use the serial number is incremented and written out to the file again.
465 The default filename consists of the CA certificate file base name with
466 F<.srl> appended. For example if the CA certificate file is called
467 F<mycacert.pem> it expects to find a serial number file called
470 =item B<-CAcreateserial>
472 With this option the CA serial number file is created if it does not exist:
473 it will contain the serial number "02" and the certificate being signed will
474 have the 1 as its serial number. If the B<-CA> option is specified
475 and the serial number file does not exist a random number is generated;
476 this is the recommended practice.
478 =item B<-extfile> I<filename>
480 File containing certificate extensions to use. If not specified then
481 no extensions are added to the certificate.
483 =item B<-extensions> I<section>
485 The section to add certificate extensions from. If this option is not
486 specified then the extensions should either be contained in the unnamed
487 (default) section or the default section should contain a variable called
488 "extensions" which contains the section to use. See the
489 L<x509v3_config(5)> manual page for details of the
490 extension section format.
494 Generate a certificate from scratch, not using an input certificate
495 or certificate request. So the B<-in> option must not be used in this case.
496 Instead, the B<-subj> and <-force_pubkey> options need to be given.
498 =item B<-next_serial>
500 Set the serial to be one more than the number in the certificate.
504 Do not generate or output a certificate.
506 =item B<-force_pubkey> I<filename>
508 When a certificate is created set its public key to the key in I<filename>
509 instead of the key contained in the input or given with the B<-signkey> option.
511 This option is useful for creating self-issued certificates that are not
512 self-signed, for instance when the key cannot be used for signing, such as DH.
513 It can also be used in conjunction with b<-new> and B<-subj> to directly
514 generate a certificate containing any desired public key.
516 =item B<-subj> I<arg>
518 When a certificate is created set its subject name to the given value.
519 The arg must be formatted as C</type0=value0/type1=value1/type2=...>.
520 Keyword characters may be escaped by \ (backslash), and whitespace is retained.
521 Empty values are permitted, but the corresponding type will not be included
522 in the certificate. Giving a single C</> will lead to an empty sequence of RDNs
525 Unless the B<-CA> option is given the issuer is set to the same value.
527 This option can be used in conjunction with the B<-force_pubkey> option
528 to create a certificate even without providing an input certificate
529 or certificate request.
535 As well as customising the name output format, it is also possible to
536 customise the actual fields printed using the B<certopt> options when
537 the B<text> option is present. The default behaviour is to print all fields.
543 Use the old format. This is equivalent to specifying no output options at all.
547 Don't print header information: that is the lines saying "Certificate"
552 Don't print out the version number.
556 Don't print out the serial number.
560 Don't print out the signature algorithm used.
564 Don't print the validity, that is the B<notBefore> and B<notAfter> fields.
568 Don't print out the subject name.
572 Don't print out the issuer name.
576 Don't print out the public key.
580 Don't give a hexadecimal dump of the certificate signature.
584 Don't print out certificate trust information.
586 =item B<no_extensions>
588 Don't print out any X509V3 extensions.
592 Retain default extension behaviour: attempt to print out unsupported
593 certificate extensions.
597 Print an error message for unsupported certificate extensions.
601 ASN1 parse unsupported extensions.
605 Hex dump unsupported extensions.
609 The value used by L<openssl-ca(1)>, equivalent to B<no_issuer>, B<no_pubkey>,
610 B<no_header>, and B<no_version>.
616 Note: in these examples the '\' means the example should be all on one
619 Display the contents of a certificate:
621 openssl x509 -in cert.pem -noout -text
623 Display the "Subject Alternative Name" extension of a certificate:
625 openssl x509 -in cert.pem -noout -ext subjectAltName
627 Display more extensions of a certificate:
629 openssl x509 -in cert.pem -noout -ext subjectAltName,nsCertType
631 Display the certificate serial number:
633 openssl x509 -in cert.pem -noout -serial
635 Display the certificate subject name:
637 openssl x509 -in cert.pem -noout -subject
639 Display the certificate subject name in RFC2253 form:
641 openssl x509 -in cert.pem -noout -subject -nameopt RFC2253
643 Display the certificate subject name in oneline form on a terminal
646 openssl x509 -in cert.pem -noout -subject -nameopt oneline,-esc_msb
648 Display the certificate SHA1 fingerprint:
650 openssl x509 -sha1 -in cert.pem -noout -fingerprint
652 Convert a certificate from PEM to DER format:
654 openssl x509 -in cert.pem -inform PEM -out cert.der -outform DER
656 Convert a certificate to a certificate request:
658 openssl x509 -x509toreq -in cert.pem -out req.pem -signkey key.pem
660 Convert a certificate request into a self signed certificate using
663 openssl x509 -req -in careq.pem -extfile openssl.cnf -extensions v3_ca \
664 -signkey key.pem -out cacert.pem
666 Sign a certificate request using the CA certificate above and add user
667 certificate extensions:
669 openssl x509 -req -in req.pem -extfile openssl.cnf -extensions v3_usr \
670 -CA cacert.pem -CAkey key.pem -CAcreateserial
673 Set a certificate to be trusted for SSL client use and change set its alias to
676 openssl x509 -in cert.pem -addtrust clientAuth \
677 -setalias "Steve's Class 1 CA" -out trust.pem
681 The conversion to UTF8 format used with the name options assumes that
682 T61Strings use the ISO8859-1 character set. This is wrong but Netscape
683 and MSIE do this as do many certificates. So although this is incorrect
684 it is more likely to display the majority of certificates correctly.
686 The B<-email> option searches the subject name and the subject alternative
687 name extension. Only unique email addresses will be printed out: it will
688 not print the same address more than once.
690 =head1 CERTIFICATE EXTENSIONS
692 The B<-purpose> option checks the certificate extensions and determines
693 what the certificate can be used for. The actual checks done are rather
694 complex and include various hacks and workarounds to handle broken
695 certificates and software.
697 The same code is used when verifying untrusted certificates in chains
698 so this section is useful if a chain is rejected by the verify code.
700 The basicConstraints extension CA flag is used to determine whether the
701 certificate can be used as a CA. If the CA flag is true then it is a CA,
702 if the CA flag is false then it is not a CA. B<All> CAs should have the
705 If the basicConstraints extension is absent then the certificate is
706 considered to be a "possible CA" other extensions are checked according
707 to the intended use of the certificate. A warning is given in this case
708 because the certificate should really not be regarded as a CA: however
709 it is allowed to be a CA to work around some broken software.
711 If the certificate is a V1 certificate (and thus has no extensions) and
712 it is self signed it is also assumed to be a CA but a warning is again
713 given: this is to work around the problem of Verisign roots which are V1
714 self signed certificates.
716 If the keyUsage extension is present then additional restraints are
717 made on the uses of the certificate. A CA certificate B<must> have the
718 keyCertSign bit set if the keyUsage extension is present.
720 The extended key usage extension places additional restrictions on the
721 certificate uses. If this extension is present (whether critical or not)
722 the key can only be used for the purposes specified.
724 A complete description of each test is given below. The comments about
725 basicConstraints and keyUsage and V1 certificates above apply to B<all>
733 The extended key usage extension must be absent or include the "web client
734 authentication" OID. keyUsage must be absent or it must have the
735 digitalSignature bit set. Netscape certificate type must be absent or it must
736 have the SSL client bit set.
738 =item B<SSL Client CA>
740 The extended key usage extension must be absent or include the "web client
741 authentication" OID. Netscape certificate type must be absent or it must have
742 the SSL CA bit set: this is used as a work around if the basicConstraints
747 The extended key usage extension must be absent or include the "web server
748 authentication" and/or one of the SGC OIDs. keyUsage must be absent or it
749 must have the digitalSignature, the keyEncipherment set or both bits set.
750 Netscape certificate type must be absent or have the SSL server bit set.
752 =item B<SSL Server CA>
754 The extended key usage extension must be absent or include the "web server
755 authentication" and/or one of the SGC OIDs. Netscape certificate type must
756 be absent or the SSL CA bit must be set: this is used as a work around if the
757 basicConstraints extension is absent.
759 =item B<Netscape SSL Server>
761 For Netscape SSL clients to connect to an SSL server it must have the
762 keyEncipherment bit set if the keyUsage extension is present. This isn't
763 always valid because some cipher suites use the key for digital signing.
764 Otherwise it is the same as a normal SSL server.
766 =item B<Common S/MIME Client Tests>
768 The extended key usage extension must be absent or include the "email
769 protection" OID. Netscape certificate type must be absent or should have the
770 S/MIME bit set. If the S/MIME bit is not set in Netscape certificate type
771 then the SSL client bit is tolerated as an alternative but a warning is shown:
772 this is because some Verisign certificates don't set the S/MIME bit.
774 =item B<S/MIME Signing>
776 In addition to the common S/MIME client tests the digitalSignature bit or
777 the nonRepudiation bit must be set if the keyUsage extension is present.
779 =item B<S/MIME Encryption>
781 In addition to the common S/MIME tests the keyEncipherment bit must be set
782 if the keyUsage extension is present.
786 The extended key usage extension must be absent or include the "email
787 protection" OID. Netscape certificate type must be absent or must have the
788 S/MIME CA bit set: this is used as a work around if the basicConstraints
793 The keyUsage extension must be absent or it must have the CRL signing bit
796 =item B<CRL Signing CA>
798 The normal CA tests apply. Except in this case the basicConstraints extension
805 Extensions in certificates are not transferred to certificate requests and
808 It is possible to produce invalid certificates or requests by specifying the
809 wrong private key or using inconsistent options in some cases: these should
812 There should be options to explicitly set such things as start and end
813 dates rather than an offset from the current time.
820 L<openssl-genrsa(1)>,
821 L<openssl-gendsa(1)>,
822 L<openssl-verify(1)>,
827 The hash algorithm used in the B<-subject_hash> and B<-issuer_hash> options
828 before OpenSSL 1.0.0 was based on the deprecated MD5 algorithm and the encoding
829 of the distinguished name. In OpenSSL 1.0.0 and later it is based on a canonical
830 version of the DN using SHA1. This means that any directories using the old
831 form must have their links rebuilt using L<openssl-rehash(1)> or similar.
833 All B<-keyform> and B<-CAkeyform> values except B<ENGINE>
834 have become obsolete in OpenSSL 3.0.0 and have no effect.
836 The B<-CAform> option has become obsolete in OpenSSL 3.0.0 and has no effect.
840 Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
842 Licensed under the Apache License 2.0 (the "License"). You may not use
843 this file except in compliance with the License. You can obtain a copy
844 in the file LICENSE in the source distribution or at
845 L<https://www.openssl.org/source/license.html>.