5 verify - Utility to verify certificates.
12 [B<-CApath directory>]
15 [B<-attime timestamp>]
41 [B<-verify_depth num>]
42 [B<-verify_email email>]
43 [B<-verify_hostname hostname>]
45 [B<-verify_name name>]
53 The B<verify> command verifies certificate chains.
55 =head1 COMMAND OPTIONS
61 Print out a usage message.
65 A B<file> of trusted certificates.
66 The file should contain one or more certificates in PEM format.
68 =item B<-CApath directory>
70 A directory of trusted certificates. The certificates should have names
71 of the form: hash.0 or have symbolic links to them of this
72 form ("hash" is the hashed certificate subject name: see the B<-hash> option
73 of the B<x509> utility). Under Unix the B<c_rehash> script will automatically
74 create symbolic links to a directory of certificates.
78 Do not load the trusted CA certificates from the default file location
82 Do not load the trusted CA certificates from the default directory location
84 =item B<-attime timestamp>
86 Perform validation checks using time specified by B<timestamp> and not
87 current system time. B<timestamp> is the number of seconds since
88 01.01.1970 (UNIX time).
90 =item B<-check_ss_sig>
92 Verify the signature on the self-signed root CA. This is disabled by default
93 because it doesn't add any security.
95 =item B<-CRLfile file>
97 The B<file> should contain one or more CRLs in PEM format.
98 This option can be specified more than once to include CRLs from multiple
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
133 =item B<-ignore_critical>
135 Normally if an unhandled critical extension is present which is not
136 supported by OpenSSL the certificate is rejected (as required by RFC5280).
137 If this option is set critical extensions are ignored.
139 =item B<-inhibit_any>
141 Set policy variable inhibit-any-policy (see RFC5280).
143 =item B<-inhibit_map>
145 Set policy variable inhibit-policy-mapping (see RFC5280).
147 =item B<-partial_chain>
149 Allow verification to succeed even if a I<complete> chain cannot be built to a
150 self-signed trust-anchor, provided it is possible to construct a chain to a
151 trusted certificate that might not be self-signed.
155 Enable policy processing and add B<arg> to the user-initial-policy-set (see
156 RFC5280). The policy B<arg> can be an object name an OID in numeric form.
157 This argument can appear more than once.
159 =item B<-policy_check>
161 Enables certificate policy processing.
163 =item B<-policy_print>
165 Print out diagnostics related to policy processing.
167 =item B<-purpose purpose>
169 The intended use for the certificate. If this option is not specified,
170 B<verify> will not consider certificate purpose during chain verification.
171 Currently accepted uses are B<sslclient>, B<sslserver>, B<nssslserver>,
172 B<smimesign>, B<smimeencrypt>. See the B<VERIFY OPERATION> section for more
175 =item B<-suiteB_128_only>, B<-suiteB_128>, B<-suiteB_192>
177 enable the Suite B mode operation at 128 bit Level of Security, 128 bit or
178 192 bit, or only 192 bit Level of Security respectively.
179 See RFC6460 for details. In particular the supported signature algorithms are
180 reduced to support only ECDSA and SHA256 or SHA384 and only the elliptic curves
183 =item B<-trusted_first>
185 When constructing the certificate chain, use the trusted certificates specified
186 via B<-CAfile>, B<-CApath> or B<-trusted> before any certificates specified via
188 This can be useful in environments with Bridge or Cross-Certified CAs.
189 As of OpenSSL 1.1.0 this option is on by default and cannot be disabled.
191 =item B<-no_alt_chains>
193 By default, unless B<-trusted_first> is specified, when building a certificate
194 chain, if the first certificate chain found is not trusted, then OpenSSL will
195 attempt to replace untrusted issuer certificates with certificates from the
196 trust store to see if an alternative chain can be found that is trusted.
197 As of OpenSSL 1.1.0, with B<-trusted_first> always on, this option has no
200 =item B<-untrusted file>
202 A B<file> of additional untrusted certificates (intermediate issuer CAs) used
203 to construct a certificate chain from the subject certificate to a trust-anchor.
204 The B<file> should contain one or more certificates in PEM format.
205 This option can be specified more than once to include untrusted certiificates
206 from multiple B<files>.
208 =item B<-trusted file>
210 A B<file> of trusted certificates, which must be self-signed, unless the
211 B<-partial_chain> option is specified.
212 The B<file> contain one or more certificates in PEM format.
213 With this option, no additional (e.g., default) certificate lists are
215 That is, the only trust-anchors are those listed in B<file>.
216 This option can be specified more than once to include trusted certificates
217 from multiple B<files>.
218 This option implies the B<-no-CAfile> and B<-no-CApath> options.
219 This option cannot be used in combination with either of the B<-CAfile> or
224 Enable support for delta CRLs.
228 Print extra information about the operations being performed.
230 =item B<-verify_depth num>
232 Limit the maximum depth of the certificate chain to B<num> certificates.
234 =item B<-verify_email email>
236 Verify if the B<email> matches the email address in Subject Alternative Name or
237 the email in the subject Distinguished Name.
239 =item B<-verify_hostname hostname>
241 Verify if the B<hostname> matches DNS name in Subject Alternative Name or
242 Common Name in the subject certificate.
244 =item B<-verify_ip ip>
246 Verify if the B<ip> matches the IP address in Subject Alternative Name of
247 the subject certificate.
249 =item B<-verify_name name>
251 Use default verification policies like trust model and required certificate
252 policies identified by B<name>.
253 The trust model determines which auxiliary trust or reject OIDs are applicable
254 to verifying the given certificate chain.
255 See the B<-addtrust> and B<-addreject> options of the L<x509(1)> command-line
257 Supported policy names include: B<default>, B<pkcs7>, B<smime_sign>,
258 B<ssl_client>, B<ssl_server>.
259 These mimics the combinations of purpose and trust settings used in SSL, CMS
261 As of OpenSSL 1.1.0, the trust model is inferred from the purpose when not
262 specified, so the B<-verify_name> options are functionally equivalent to the
263 corresponding B<-purpose> settings.
265 =item B<-x509_strict>
267 For strict X.509 compliance, disable non-compliant workarounds for broken
272 Display information about the certificate chain that has been built (if
273 successful). Certificates in the chain that came from the untrusted list will be
274 flagged as "untrusted".
278 Indicates the last option. All arguments following this are assumed to be
279 certificate files. This is useful if the first certificate filename begins
282 =item B<certificates>
284 One or more certificates to verify. If no certificates are given, B<verify>
285 will attempt to read a certificate from standard input. Certificates must be
290 =head1 VERIFY OPERATION
292 The B<verify> program uses the same functions as the internal SSL and S/MIME
293 verification, therefore this description applies to these verify operations
296 There is one crucial difference between the verify operations performed
297 by the B<verify> program: wherever possible an attempt is made to continue
298 after an error whereas normally the verify operation would halt on the
299 first error. This allows all the problems with a certificate chain to be
302 The verify operation consists of a number of separate steps.
304 Firstly a certificate chain is built up starting from the supplied certificate
305 and ending in the root CA.
306 It is an error if the whole chain cannot be built up.
307 The chain is built up by looking up the issuers certificate of the current
309 If a certificate is found which is its own issuer it is assumed to be the root
312 The process of 'looking up the issuers certificate' itself involves a number of
314 Ater all certificates whose subject name matches the issuer name of the current
315 certificate are subject to further tests.
316 The relevant authority key identifier components of the current certificate (if
317 present) must match the subject key identifier (if present) and issuer and
318 serial number of the candidate issuer, in addition the keyUsage extension of
319 the candidate issuer (if present) must permit certificate signing.
321 The lookup first looks in the list of untrusted certificates and if no match
322 is found the remaining lookups are from the trusted certificates. The root CA
323 is always looked up in the trusted certificate list: if the certificate to
324 verify is a root certificate then an exact match must be found in the trusted
327 The second operation is to check every untrusted certificate's extensions for
328 consistency with the supplied purpose. If the B<-purpose> option is not included
329 then no checks are done. The supplied or "leaf" certificate must have extensions
330 compatible with the supplied purpose and all other certificates must also be valid
331 CA certificates. The precise extensions required are described in more detail in
332 the B<CERTIFICATE EXTENSIONS> section of the B<x509> utility.
334 The third operation is to check the trust settings on the root CA. The root CA
335 should be trusted for the supplied purpose.
336 For compatibility with previous versions of OpenSSL, a certificate with no
337 trust settings is considered to be valid for all purposes.
339 The final operation is to check the validity of the certificate chain. The validity
340 period is checked against the current system time and the notBefore and notAfter
341 dates in the certificate. The certificate signatures are also checked at this
344 If all operations complete successfully then certificate is considered valid. If
345 any operation fails then the certificate is not valid.
349 When a verify operation fails the output messages can be somewhat cryptic. The
350 general form of the error message is:
352 server.pem: /C=AU/ST=Queensland/O=CryptSoft Pty Ltd/CN=Test CA (1024 bit)
353 error 24 at 1 depth lookup:invalid CA certificate
355 The first line contains the name of the certificate being verified followed by
356 the subject name of the certificate. The second line contains the error number
357 and the depth. The depth is number of the certificate being verified when a
358 problem was detected starting with zero for the certificate being verified itself
359 then 1 for the CA that signed the certificate and so on. Finally a text version
360 of the error number is presented.
362 An partial list of the error codes and messages is shown below, this also
363 includes the name of the error code as defined in the header file x509_vfy.h
364 Some of the error codes are defined but never returned: these are described
369 =item B<0 X509_V_OK: ok>
371 the operation was successful.
373 =item B<1 X509_V_ERR_UNSPECIFIED: unspecified certificate verification error>
375 unspecified error, should not happen.
377 =item B<2 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT: unable to get issuer certificate>
379 the issuer certificate of a looked up certificate could not be found. This
380 normally means the list of trusted certificates is not complete.
382 =item B<3 X509_V_ERR_UNABLE_TO_GET_CRL: unable to get certificate CRL>
384 the CRL of a certificate could not be found.
386 =item B<4 X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE: unable to decrypt certificate's signature>
388 the certificate signature could not be decrypted. This means that the actual signature value
389 could not be determined rather than it not matching the expected value, this is only
390 meaningful for RSA keys.
392 =item B<5 X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE: unable to decrypt CRL's signature>
394 the CRL 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. Unused.
397 =item B<6 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY: unable to decode issuer public key>
399 the public key in the certificate SubjectPublicKeyInfo could not be read.
401 =item B<7 X509_V_ERR_CERT_SIGNATURE_FAILURE: certificate signature failure>
403 the signature of the certificate is invalid.
405 =item B<8 X509_V_ERR_CRL_SIGNATURE_FAILURE: CRL signature failure>
407 the signature of the certificate is invalid.
409 =item B<9 X509_V_ERR_CERT_NOT_YET_VALID: certificate is not yet valid>
411 the certificate is not yet valid: the notBefore date is after the current time.
413 =item B<10 X509_V_ERR_CERT_HAS_EXPIRED: certificate has expired>
415 the certificate has expired: that is the notAfter date is before the current time.
417 =item B<11 X509_V_ERR_CRL_NOT_YET_VALID: CRL is not yet valid>
419 the CRL is not yet valid.
421 =item B<12 X509_V_ERR_CRL_HAS_EXPIRED: CRL has expired>
425 =item B<13 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD: format error in certificate's notBefore field>
427 the certificate notBefore field contains an invalid time.
429 =item B<14 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD: format error in certificate's notAfter field>
431 the certificate notAfter field contains an invalid time.
433 =item B<15 X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD: format error in CRL's lastUpdate field>
435 the CRL lastUpdate field contains an invalid time.
437 =item B<16 X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD: format error in CRL's nextUpdate field>
439 the CRL nextUpdate field contains an invalid time.
441 =item B<17 X509_V_ERR_OUT_OF_MEM: out of memory>
443 an error occurred trying to allocate memory. This should never happen.
445 =item B<18 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT: self signed certificate>
447 the passed certificate is self signed and the same certificate cannot be found in the list of
448 trusted certificates.
450 =item B<19 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN: self signed certificate in certificate chain>
452 the certificate chain could be built up using the untrusted certificates but the root could not
455 =item B<20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: unable to get local issuer certificate>
457 the issuer certificate could not be found: this occurs if the issuer
458 certificate of an untrusted certificate cannot be found.
460 =item B<21 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE: unable to verify the first certificate>
462 no signatures could be verified because the chain contains only one certificate and it is not
465 =item B<22 X509_V_ERR_CERT_CHAIN_TOO_LONG: certificate chain too long>
467 the certificate chain length is greater than the supplied maximum depth. Unused.
469 =item B<23 X509_V_ERR_CERT_REVOKED: certificate revoked>
471 the certificate has been revoked.
473 =item B<24 X509_V_ERR_INVALID_CA: invalid CA certificate>
475 a CA certificate is invalid. Either it is not a CA or its extensions are not consistent
476 with the supplied purpose.
478 =item B<25 X509_V_ERR_PATH_LENGTH_EXCEEDED: path length constraint exceeded>
480 the basicConstraints pathlength parameter has been exceeded.
482 =item B<26 X509_V_ERR_INVALID_PURPOSE: unsupported certificate purpose>
484 the supplied certificate cannot be used for the specified purpose.
486 =item B<27 X509_V_ERR_CERT_UNTRUSTED: certificate not trusted>
488 the root CA is not marked as trusted for the specified purpose.
490 =item B<28 X509_V_ERR_CERT_REJECTED: certificate rejected>
492 the root CA is marked to reject the specified purpose.
494 =item B<29 X509_V_ERR_SUBJECT_ISSUER_MISMATCH: subject issuer mismatch>
496 Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
497 B<-issuer_checks> option.
499 =item B<30 X509_V_ERR_AKID_SKID_MISMATCH: authority and subject key identifier mismatch>
501 Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
502 B<-issuer_checks> option.
504 =item B<31 X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH: authority and issuer serial number mismatch>
506 Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
507 B<-issuer_checks> option.
509 =item B<32 X509_V_ERR_KEYUSAGE_NO_CERTSIGN: key usage does not include certificate signing>
511 Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
512 B<-issuer_checks> option.
514 =item B<33 X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER: unable to get CRL issuer certificate>
518 =item B<34 X509_V_ERR_UNHANDLED_CRITICAL_EXTENSION: unhandled critical extension>
522 =item B<35 X509_V_ERR_KEYUSAGE_NO_CRL_SIGN: key usage does not include CRL signing>
526 =item B<36 X509_V_ERR_UNHANDLED_CRITICAL_CRL_EXTENSION: unhandled critical CRL extension>
530 =item B<37 X509_V_ERR_INVALID_NON_CA: invalid non-CA certificate has CA markings>
534 =item B<38 X509_V_ERR_PROXY_PATH_LENGTH_EXCEEDED: proxy path length constraint exceeded>
538 =item B<39 X509_V_ERR_KEYUSAGE_NO_DIGITAL_SIGNATURE: key usage does not include digital signature>
542 =item B<40 X509_V_ERR_PROXY_CERTIFICATES_NOT_ALLOWED: proxy certificates not allowed, please set the appropriate flag>
546 =item B<41 X509_V_ERR_INVALID_EXTENSION: invalid or inconsistent certificate extension>
550 =item B<42 X509_V_ERR_INVALID_POLICY_EXTENSION: invalid or inconsistent certificate policy extension>
554 =item B<43 X509_V_ERR_NO_EXPLICIT_POLICY: no explicit policy>
558 =item B<44 X509_V_ERR_DIFFERENT_CRL_SCOPE: Different CRL scope>
562 =item B<45 X509_V_ERR_UNSUPPORTED_EXTENSION_FEATURE: Unsupported extension feature>
566 =item B<46 X509_V_ERR_UNNESTED_RESOURCE: RFC 3779 resource not subset of parent's resources>
570 =item B<47 X509_V_ERR_PERMITTED_VIOLATION: permitted subtree violation>
574 =item B<48 X509_V_ERR_EXCLUDED_VIOLATION: excluded subtree violation>
578 =item B<49 X509_V_ERR_SUBTREE_MINMAX: name constraints minimum and maximum not supported>
582 =item B<50 X509_V_ERR_APPLICATION_VERIFICATION: application verification failure>
584 an application specific error. Unused.
586 =item B<51 X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE: unsupported name constraint type>
590 =item B<52 X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX: unsupported or invalid name constraint syntax>
594 =item B<53 X509_V_ERR_UNSUPPORTED_NAME_SYNTAX: unsupported or invalid name syntax>
598 =item B<54 X509_V_ERR_CRL_PATH_VALIDATION_ERROR: CRL path validation error>
602 =item B<55 X509_V_ERR_PATH_LOOP: Path Loop>
606 =item B<56 X509_V_ERR_SUITE_B_INVALID_VERSION: Suite B: certificate version invalid>
610 =item B<57 X509_V_ERR_SUITE_B_INVALID_ALGORITHM: Suite B: invalid public key algorithm>
614 =item B<58 X509_V_ERR_SUITE_B_INVALID_CURVE: Suite B: invalid ECC curve>
618 =item B<59 X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM: Suite B: invalid signature algorithm>
622 =item B<60 X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED: Suite B: curve not allowed for this LOS>
626 =item B<61 X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256: Suite B: cannot sign P-384 with P-256>
630 =item B<62 X509_V_ERR_HOSTNAME_MISMATCH: Hostname mismatch>
634 =item B<63 X509_V_ERR_EMAIL_MISMATCH: Email address mismatch>
638 =item B<64 X509_V_ERR_IP_ADDRESS_MISMATCH: IP address mismatch>
642 =item B<65 X509_V_ERR_DANE_NO_MATCH: No matching DANE TLSA records>
644 DANE TLSA authentication is enabled, but no TLSA records matched the
646 This error is only possible in L<s_client(1)>.
652 Although the issuer checks are a considerable improvement over the old technique they still
653 suffer from limitations in the underlying X509_LOOKUP API. One consequence of this is that
654 trusted certificates with matching subject name must either appear in a file (as specified by the
655 B<-CAfile> option) or a directory (as specified by B<-CApath>). If they occur in both then only
656 the certificates in the file will be recognised.
658 Previous versions of OpenSSL assume certificates with matching subject name are identical and
661 Previous versions of this documentation swapped the meaning of the
662 B<X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT> and
663 B<20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY> error codes.
671 The B<-show_chain> option was first added to OpenSSL 1.1.0.
673 The B<-issuer_checks> option is deprecated as of OpenSSL 1.1.0 and