5 verify - Utility to verify certificates.
11 [B<-CApath directory>]
14 [B<-attime timestamp>]
42 [B<-verify_depth num>]
43 [B<-verify_email email>]
44 [B<-verify_hostname hostname>]
46 [B<-verify_name name>]
55 The B<verify> command verifies certificate chains.
57 =head1 COMMAND OPTIONS
63 A B<file> of trusted certificates.
64 The file should contain one or more certificates in PEM format.
66 =item B<-CApath directory>
68 A directory of trusted certificates. The certificates should have names
69 of the form: hash.0 or have symbolic links to them of this
70 form ("hash" is the hashed certificate subject name: see the B<-hash> option
71 of the B<x509> utility). Under Unix the B<c_rehash> script will automatically
72 create symbolic links to a directory of certificates.
76 Do not load the trusted CA certificates from the default file location
80 Do not load the trusted CA certificates from the default directory location
82 =item B<-attime timestamp>
84 Perform validation checks using time specified by B<timestamp> and not
85 current system time. B<timestamp> is the number of seconds since
86 01.01.1970 (UNIX time).
88 =item B<-check_ss_sig>
90 Verify the signature on the self-signed root CA. This is disabled by default
91 because it doesn't add any security.
93 =item B<-CRLfile file>
95 The B<file> should contain one or more CRLs in PEM format.
96 This option can be specified more than once to include CRLs from multiple
98 If you want to enable an B<engine> via the B<-engine> option, that option has
99 to be specified before this one.
101 =item B<-crl_download>
103 Attempt to download CRL information for this certificate.
107 Checks end entity certificate validity by attempting to look up a valid CRL.
108 If a valid CRL cannot be found an error occurs.
110 =item B<-crl_check_all>
112 Checks the validity of B<all> certificates in the chain by attempting
113 to look up valid CRLs.
117 Specifying an engine B<id> will cause L<verify(1)> to attempt to load the
119 The engine will then be set as the default for all its supported algorithms.
120 If you want to load certificates or CRLs that require engine support via any of
121 the B<-trusted>, B<-untrusted> or B<-CRLfile> options, the B<-engine> option
122 must be specified before those options.
124 =item B<-explicit_policy>
126 Set policy variable require-explicit-policy (see RFC5280).
128 =item B<-extended_crl>
130 Enable extended CRL features such as indirect CRLs and alternate CRL
135 Print out a usage message.
137 =item B<-ignore_critical>
139 Normally if an unhandled critical extension is present which is not
140 supported by OpenSSL the certificate is rejected (as required by RFC5280).
141 If this option is set critical extensions are ignored.
143 =item B<-inhibit_any>
145 Set policy variable inhibit-any-policy (see RFC5280).
147 =item B<-inhibit_map>
149 Set policy variable inhibit-policy-mapping (see RFC5280).
151 =item B<-issuer_checks>
153 Print out diagnostics relating to searches for the issuer certificate of the
154 current certificate. This shows why each candidate issuer certificate was
155 rejected. The presence of rejection messages does not itself imply that
156 anything is wrong; during the normal verification process, several
157 rejections may take place.
159 =item B<-partial_chain>
161 Allow verification to succeed even if a I<complete> chain cannot be built to a
162 self-signed trust-anchor, provided it is possible to construct a chain to a
163 trusted certificate that might not be self-signed.
167 Enable policy processing and add B<arg> to the user-initial-policy-set (see
168 RFC5280). The policy B<arg> can be an object name an OID in numeric form.
169 This argument can appear more than once.
171 =item B<-policy_check>
173 Enables certificate policy processing.
175 =item B<-policy_print>
177 Print out diagnostics related to policy processing.
179 =item B<-purpose purpose>
181 The intended use for the certificate. If this option is not specified,
182 B<verify> will not consider certificate purpose during chain verification.
183 Currently accepted uses are B<sslclient>, B<sslserver>, B<nssslserver>,
184 B<smimesign>, B<smimeencrypt>. See the B<VERIFY OPERATION> section for more
187 =item B<-suiteB_128_only>, B<-suiteB_128>, B<-suiteB_192>
189 enable the Suite B mode operation at 128 bit Level of Security, 128 bit or
190 192 bit, or only 192 bit Level of Security respectively.
191 See RFC6460 for details. In particular the supported signature algorithms are
192 reduced to support only ECDSA and SHA256 or SHA384 and only the elliptic curves
195 =item B<-trusted_first>
197 When constructing the certificate chain, use the trusted certificates specified
198 via B<-CAfile>, B<-CApath> or B<-trusted> before any certificates specified via
200 This can be useful in environments with Bridge or Cross-Certified CAs.
202 =item B<-no_alt_chains>
204 When building a certificate chain, if the first certificate chain found is not
205 trusted, then OpenSSL will continue to check to see if an alternative chain can
206 be found that is trusted. With this option that behaviour is suppressed so that
207 only the first chain found is ever used. Using this option will force the
208 behaviour to match that of OpenSSL versions prior to 1.1.0.
210 =item B<-untrusted file>
212 A B<file> of additional untrusted certificates (intermediate issuer CAs) used
213 to constuct a certificate chain from the subject certificate to a trust-anchor.
214 The B<file> should contain one or more certificates in PEM format.
215 This option can be specified more than once to include untrusted certiificates
216 from multiple B<files>.
217 If you want to enable an B<engine> via the B<-engine> option, that option has
218 to be specified before this one.
220 =item B<-trusted file>
222 A B<file> of trusted certificates, which must be self-signed, unless the
223 B<-partial_chain> option is specified.
224 The B<file> contain one or more certificates in PEM format.
225 With this option, no additional (e.g., default) certificate lists are
227 That is, the only trust-anchors are those listed in B<file>.
228 This option can be specified more than once to include trusted certificates
229 from multiple B<files>.
230 This option implies the B<-no-CAfile> and B<-no-CApath> options.
231 This option cannot be used in combination with either of the B<-CAfile> or
233 If you want to enable an B<engine> via the B<-engine> option, that option has
234 to be specified before this one.
238 Enable support for delta CRLs.
242 Print extra information about the operations being performed.
244 =item B<-verify_depth num>
246 Limit the maximum depth of the certificate chain to B<num> certificates.
248 =item B<-verify_email email>
250 Verify if the B<email> matches the email address in Subject Alternative Name or
251 the email in the subject Distinguished Name.
253 =item B<-verify_hostname hostname>
255 Verify if the B<hostname> matches DNS name in Subject Alternative Name or
256 Common Name in the subject certificate.
258 =item B<-verify_ip ip>
260 Verify if the B<ip> matches the IP address in Subject Alternative Name of
261 the subject certificate.
263 =item B<-verify_name name>
265 Use default verification policies like trust model and required certificate
266 policies identified by B<name>.
267 Supported policy names include: B<default>, B<pkcs7>, B<smime_sign>,
268 B<ssl_client>, B<ssl_server>.
269 This checks not only the purpose of the leaf certificate, but also the
270 trust settings of the trusted CAs.
271 When in doubt, use this option rather than B<-purpose>.
272 The B<-verify_name> option more closely matches how certificates are checked in
275 =item B<-x509_strict>
277 For strict X.509 compliance, disable non-compliant workarounds for broken
282 Display information about the certificate chain that has been built (if
283 successful). Certificates in the chain that came from the untrusted list will be
284 flagged as "untrusted".
288 Indicates the last option. All arguments following this are assumed to be
289 certificate files. This is useful if the first certificate filename begins
292 =item B<certificates>
294 One or more certificates to verify. If no certificates are given, B<verify>
295 will attempt to read a certificate from standard input. Certificates must be
300 =head1 VERIFY OPERATION
302 The B<verify> program uses the same functions as the internal SSL and S/MIME
303 verification, therefore this description applies to these verify operations
306 There is one crucial difference between the verify operations performed
307 by the B<verify> program: wherever possible an attempt is made to continue
308 after an error whereas normally the verify operation would halt on the
309 first error. This allows all the problems with a certificate chain to be
312 The verify operation consists of a number of separate steps.
314 Firstly a certificate chain is built up starting from the supplied certificate
315 and ending in the root CA.
316 It is an error if the whole chain cannot be built up.
317 The chain is built up by looking up the issuers certificate of the current
319 If a certificate is found which is its own issuer it is assumed to be the root
322 The process of 'looking up the issuers certificate' itself involves a number of
324 Ater all certificates whose subject name matches the issuer name of the current
325 certificate are subject to further tests.
326 The relevant authority key identifier components of the current certificate (if
327 present) must match the subject key identifier (if present) and issuer and
328 serial number of the candidate issuer, in addition the keyUsage extension of
329 the candidate issuer (if present) must permit certificate signing.
331 The lookup first looks in the list of untrusted certificates and if no match
332 is found the remaining lookups are from the trusted certificates. The root CA
333 is always looked up in the trusted certificate list: if the certificate to
334 verify is a root certificate then an exact match must be found in the trusted
337 The second operation is to check every untrusted certificate's extensions for
338 consistency with the supplied purpose. If the B<-purpose> option is not included
339 then no checks are done. The supplied or "leaf" certificate must have extensions
340 compatible with the supplied purpose and all other certificates must also be valid
341 CA certificates. The precise extensions required are described in more detail in
342 the B<CERTIFICATE EXTENSIONS> section of the B<x509> utility.
344 The third operation is to check the trust settings on the root CA. The root CA
345 should be trusted for the supplied purpose.
346 For compatibility with previous versions of OpenSSL, a certificate with no
347 trust settings is considered to be valid for all purposes.
349 The final operation is to check the validity of the certificate chain. The validity
350 period is checked against the current system time and the notBefore and notAfter
351 dates in the certificate. The certificate signatures are also checked at this
354 If all operations complete successfully then certificate is considered valid. If
355 any operation fails then the certificate is not valid.
359 When a verify operation fails the output messages can be somewhat cryptic. The
360 general form of the error message is:
362 server.pem: /C=AU/ST=Queensland/O=CryptSoft Pty Ltd/CN=Test CA (1024 bit)
363 error 24 at 1 depth lookup:invalid CA certificate
365 The first line contains the name of the certificate being verified followed by
366 the subject name of the certificate. The second line contains the error number
367 and the depth. The depth is number of the certificate being verified when a
368 problem was detected starting with zero for the certificate being verified itself
369 then 1 for the CA that signed the certificate and so on. Finally a text version
370 of the error number is presented.
372 An partial list of the error codes and messages is shown below, this also
373 includes the name of the error code as defined in the header file x509_vfy.h
374 Some of the error codes are defined but never returned: these are described
379 =item B<0 X509_V_OK: ok>
381 the operation was successful.
383 =item B<2 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT: unable to get issuer certificate>
385 the issuer certificate of a looked up certificate could not be found. This
386 normally means the list of trusted certificates is not complete.
388 =item B<3 X509_V_ERR_UNABLE_TO_GET_CRL: unable to get certificate CRL>
390 the CRL of a certificate could not be found.
392 =item B<4 X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE: unable to decrypt certificate's signature>
394 the certificate signature could not be decrypted. This means that the actual signature value
395 could not be determined rather than it not matching the expected value, this is only
396 meaningful for RSA keys.
398 =item B<5 X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE: unable to decrypt CRL's signature>
400 the CRL signature could not be decrypted: this means that the actual signature value
401 could not be determined rather than it not matching the expected value. Unused.
403 =item B<6 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY: unable to decode issuer public key>
405 the public key in the certificate SubjectPublicKeyInfo could not be read.
407 =item B<7 X509_V_ERR_CERT_SIGNATURE_FAILURE: certificate signature failure>
409 the signature of the certificate is invalid.
411 =item B<8 X509_V_ERR_CRL_SIGNATURE_FAILURE: CRL signature failure>
413 the signature of the certificate is invalid.
415 =item B<9 X509_V_ERR_CERT_NOT_YET_VALID: certificate is not yet valid>
417 the certificate is not yet valid: the notBefore date is after the current time.
419 =item B<10 X509_V_ERR_CERT_HAS_EXPIRED: certificate has expired>
421 the certificate has expired: that is the notAfter date is before the current time.
423 =item B<11 X509_V_ERR_CRL_NOT_YET_VALID: CRL is not yet valid>
425 the CRL is not yet valid.
427 =item B<12 X509_V_ERR_CRL_HAS_EXPIRED: CRL has expired>
431 =item B<13 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD: format error in certificate's notBefore field>
433 the certificate notBefore field contains an invalid time.
435 =item B<14 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD: format error in certificate's notAfter field>
437 the certificate notAfter field contains an invalid time.
439 =item B<15 X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD: format error in CRL's lastUpdate field>
441 the CRL lastUpdate field contains an invalid time.
443 =item B<16 X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD: format error in CRL's nextUpdate field>
445 the CRL nextUpdate field contains an invalid time.
447 =item B<17 X509_V_ERR_OUT_OF_MEM: out of memory>
449 an error occurred trying to allocate memory. This should never happen.
451 =item B<18 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT: self signed certificate>
453 the passed certificate is self signed and the same certificate cannot be found in the list of
454 trusted certificates.
456 =item B<19 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN: self signed certificate in certificate chain>
458 the certificate chain could be built up using the untrusted certificates but the root could not
461 =item B<20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: unable to get local issuer certificate>
463 the issuer certificate could not be found: this occurs if the issuer
464 certificate of an untrusted certificate cannot be found.
466 =item B<21 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE: unable to verify the first certificate>
468 no signatures could be verified because the chain contains only one certificate and it is not
471 =item B<22 X509_V_ERR_CERT_CHAIN_TOO_LONG: certificate chain too long>
473 the certificate chain length is greater than the supplied maximum depth. Unused.
475 =item B<23 X509_V_ERR_CERT_REVOKED: certificate revoked>
477 the certificate has been revoked.
479 =item B<24 X509_V_ERR_INVALID_CA: invalid CA certificate>
481 a CA certificate is invalid. Either it is not a CA or its extensions are not consistent
482 with the supplied purpose.
484 =item B<25 X509_V_ERR_PATH_LENGTH_EXCEEDED: path length constraint exceeded>
486 the basicConstraints pathlength parameter has been exceeded.
488 =item B<26 X509_V_ERR_INVALID_PURPOSE: unsupported certificate purpose>
490 the supplied certificate cannot be used for the specified purpose.
492 =item B<27 X509_V_ERR_CERT_UNTRUSTED: certificate not trusted>
494 the root CA is not marked as trusted for the specified purpose.
496 =item B<28 X509_V_ERR_CERT_REJECTED: certificate rejected>
498 the root CA is marked to reject the specified purpose.
500 =item B<29 X509_V_ERR_SUBJECT_ISSUER_MISMATCH: subject issuer mismatch>
502 the current candidate issuer certificate was rejected because its subject name
503 did not match the issuer name of the current certificate. Only displayed when
504 the B<-issuer_checks> option is set.
506 =item B<30 X509_V_ERR_AKID_SKID_MISMATCH: authority and subject key identifier mismatch>
508 the current candidate issuer certificate was rejected because its subject key
509 identifier was present and did not match the authority key identifier current
510 certificate. Only displayed when the B<-issuer_checks> option is set.
512 =item B<31 X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH: authority and issuer serial number mismatch>
514 the current candidate issuer certificate was rejected because its issuer name
515 and serial number was present and did not match the authority key identifier
516 of the current certificate. Only displayed when the B<-issuer_checks> option is set.
518 =item B<32 X509_V_ERR_KEYUSAGE_NO_CERTSIGN:key usage does not include certificate signing>
520 the current candidate issuer certificate was rejected because its keyUsage extension
521 does not permit certificate signing.
523 =item B<50 X509_V_ERR_APPLICATION_VERIFICATION: application verification failure>
525 an application specific error. Unused.
531 Although the issuer checks are a considerable improvement over the old technique they still
532 suffer from limitations in the underlying X509_LOOKUP API. One consequence of this is that
533 trusted certificates with matching subject name must either appear in a file (as specified by the
534 B<-CAfile> option) or a directory (as specified by B<-CApath>). If they occur in both then only
535 the certificates in the file will be recognised.
537 Previous versions of OpenSSL assume certificates with matching subject name are identical and
540 Previous versions of this documentation swapped the meaning of the
541 B<X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT> and
542 B<20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY> error codes.
550 The -show_chain option was first added to OpenSSL 1.1.0.