.\" Automatically generated by Pod::Man 2.22 (Pod::Simple 3.13) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. 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Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" verify \- Utility to verify certificates. .SH "SYNOPSIS" .IX Header "SYNOPSIS" \&\fBopenssl\fR \fBverify\fR [\fB\-CApath directory\fR] [\fB\-CAfile file\fR] [\fB\-purpose purpose\fR] [\fB\-policy arg\fR] [\fB\-ignore_critical\fR] [\fB\-attime timestamp\fR] [\fB\-check_ss_sig\fR] [\fB\-crlfile file\fR] [\fB\-crl_download\fR] [\fB\-crl_check\fR] [\fB\-crl_check_all\fR] [\fB\-policy_check\fR] [\fB\-explicit_policy\fR] [\fB\-inhibit_any\fR] [\fB\-inhibit_map\fR] [\fB\-x509_strict\fR] [\fB\-extended_crl\fR] [\fB\-use_deltas\fR] [\fB\-policy_print\fR] [\fB\-no_alt_chains\fR] [\fB\-untrusted file\fR] [\fB\-help\fR] [\fB\-issuer_checks\fR] [\fB\-trusted file\fR] [\fB\-verbose\fR] [\fB\-\fR] [certificates] .SH "DESCRIPTION" .IX Header "DESCRIPTION" The \fBverify\fR command verifies certificate chains. .SH "COMMAND OPTIONS" .IX Header "COMMAND OPTIONS" .IP "\fB\-CApath directory\fR" 4 .IX Item "-CApath directory" A directory of trusted certificates. The certificates should have names of the form: hash.0 or have symbolic links to them of this form (\*(L"hash\*(R" is the hashed certificate subject name: see the \fB\-hash\fR option of the \fBx509\fR utility). Under Unix the \fBc_rehash\fR script will automatically create symbolic links to a directory of certificates. .IP "\fB\-CAfile file\fR A file of trusted certificates. The file should contain multiple certificates in \s-1PEM\s0 format concatenated together." 4 .IX Item "-CAfile file A file of trusted certificates. The file should contain multiple certificates in PEM format concatenated together." .PD 0 .IP "\fB\-attime timestamp\fR" 4 .IX Item "-attime timestamp" .PD Perform validation checks using time specified by \fBtimestamp\fR and not current system time. \fBtimestamp\fR is the number of seconds since 01.01.1970 (\s-1UNIX\s0 time). .IP "\fB\-check_ss_sig\fR" 4 .IX Item "-check_ss_sig" Verify the signature on the self-signed root \s-1CA\s0. This is disabled by default because it doesn't add any security. .IP "\fB\-crlfile file\fR" 4 .IX Item "-crlfile file" File containing one or more \s-1CRL\s0's (in \s-1PEM\s0 format) to load. .IP "\fB\-crl_download\fR" 4 .IX Item "-crl_download" Attempt to download \s-1CRL\s0 information for this certificate. .IP "\fB\-crl_check\fR" 4 .IX Item "-crl_check" Checks end entity certificate validity by attempting to look up a valid \s-1CRL\s0. If a valid \s-1CRL\s0 cannot be found an error occurs. .IP "\fB\-untrusted file\fR" 4 .IX Item "-untrusted file" A file of untrusted certificates. The file should contain multiple certificates in \s-1PEM\s0 format concatenated together. .IP "\fB\-purpose purpose\fR" 4 .IX Item "-purpose purpose" The intended use for the certificate. If this option is not specified, \&\fBverify\fR will not consider certificate purpose during chain verification. Currently accepted uses are \fBsslclient\fR, \fBsslserver\fR, \fBnssslserver\fR, \&\fBsmimesign\fR, \fBsmimeencrypt\fR. See the \fB\s-1VERIFY\s0 \s-1OPERATION\s0\fR section for more information. .IP "\fB\-help\fR" 4 .IX Item "-help" Print out a usage message. .IP "\fB\-verbose\fR" 4 .IX Item "-verbose" Print extra information about the operations being performed. .IP "\fB\-issuer_checks\fR" 4 .IX Item "-issuer_checks" Print out diagnostics relating to searches for the issuer certificate of the current certificate. This shows why each candidate issuer certificate was rejected. The presence of rejection messages does not itself imply that anything is wrong; during the normal verification process, several rejections may take place. .IP "\fB\-policy arg\fR" 4 .IX Item "-policy arg" Enable policy processing and add \fBarg\fR to the user-initial-policy-set (see \&\s-1RFC5280\s0). The policy \fBarg\fR can be an object name an \s-1OID\s0 in numeric form. This argument can appear more than once. .IP "\fB\-policy_check\fR" 4 .IX Item "-policy_check" Enables certificate policy processing. .IP "\fB\-explicit_policy\fR" 4 .IX Item "-explicit_policy" Set policy variable require-explicit-policy (see \s-1RFC5280\s0). .IP "\fB\-inhibit_any\fR" 4 .IX Item "-inhibit_any" Set policy variable inhibit-any-policy (see \s-1RFC5280\s0). .IP "\fB\-inhibit_map\fR" 4 .IX Item "-inhibit_map" Set policy variable inhibit-policy-mapping (see \s-1RFC5280\s0). .IP "\fB\-no_alt_chains\fR" 4 .IX Item "-no_alt_chains" When building a certificate chain, if the first certificate chain found is not trusted, then OpenSSL will continue to check to see if an alternative chain can be found that is trusted. With this option that behaviour is suppressed so that only the first chain found is ever used. Using this option will force the behaviour to match that of previous OpenSSL versions. .IP "\fB\-trusted file\fR" 4 .IX Item "-trusted file" A file of additional trusted certificates. The file should contain multiple certificates in \s-1PEM\s0 format concatenated together. .IP "\fB\-policy_print\fR" 4 .IX Item "-policy_print" Print out diagnostics related to policy processing. .IP "\fB\-crl_check\fR" 4 .IX Item "-crl_check" Checks end entity certificate validity by attempting to look up a valid \s-1CRL\s0. If a valid \s-1CRL\s0 cannot be found an error occurs. .IP "\fB\-crl_check_all\fR" 4 .IX Item "-crl_check_all" Checks the validity of \fBall\fR certificates in the chain by attempting to look up valid CRLs. .IP "\fB\-ignore_critical\fR" 4 .IX Item "-ignore_critical" Normally if an unhandled critical extension is present which is not supported by OpenSSL the certificate is rejected (as required by \s-1RFC5280\s0). If this option is set critical extensions are ignored. .IP "\fB\-x509_strict\fR" 4 .IX Item "-x509_strict" For strict X.509 compliance, disable non-compliant workarounds for broken certificates. .IP "\fB\-extended_crl\fR" 4 .IX Item "-extended_crl" Enable extended \s-1CRL\s0 features such as indirect CRLs and alternate \s-1CRL\s0 signing keys. .IP "\fB\-use_deltas\fR" 4 .IX Item "-use_deltas" Enable support for delta CRLs. .IP "\fB\-check_ss_sig\fR" 4 .IX Item "-check_ss_sig" Verify the signature on the self-signed root \s-1CA\s0. This is disabled by default because it doesn't add any security. .IP "\fB\-\fR" 4 .IX Item "-" Indicates the last option. All arguments following this are assumed to be certificate files. This is useful if the first certificate filename begins with a \fB\-\fR. .IP "\fBcertificates\fR" 4 .IX Item "certificates" One or more certificates to verify. If no certificates are given, \fBverify\fR will attempt to read a certificate from standard input. Certificates must be in \s-1PEM\s0 format. .SH "VERIFY OPERATION" .IX Header "VERIFY OPERATION" The \fBverify\fR program uses the same functions as the internal \s-1SSL\s0 and S/MIME verification, therefore this description applies to these verify operations too. .PP There is one crucial difference between the verify operations performed by the \fBverify\fR program: wherever possible an attempt is made to continue after an error whereas normally the verify operation would halt on the first error. This allows all the problems with a certificate chain to be determined. .PP The verify operation consists of a number of separate steps. .PP Firstly a certificate chain is built up starting from the supplied certificate and ending in the root \s-1CA\s0. It is an error if the whole chain cannot be built up. The chain is built up by looking up the issuers certificate of the current certificate. If a certificate is found which is its own issuer it is assumed to be the root \s-1CA\s0. .PP The process of 'looking up the issuers certificate' itself involves a number of steps. In versions of OpenSSL before 0.9.5a the first certificate whose subject name matched the issuer of the current certificate was assumed to be the issuers certificate. In OpenSSL 0.9.6 and later all certificates whose subject name matches the issuer name of the current certificate are subject to further tests. The relevant authority key identifier components of the current certificate (if present) must match the subject key identifier (if present) and issuer and serial number of the candidate issuer, in addition the keyUsage extension of the candidate issuer (if present) must permit certificate signing. .PP The lookup first looks in the list of untrusted certificates and if no match is found the remaining lookups are from the trusted certificates. The root \s-1CA\s0 is always looked up in the trusted certificate list: if the certificate to verify is a root certificate then an exact match must be found in the trusted list. .PP The second operation is to check every untrusted certificate's extensions for consistency with the supplied purpose. If the \fB\-purpose\fR option is not included then no checks are done. The supplied or \*(L"leaf\*(R" certificate must have extensions compatible with the supplied purpose and all other certificates must also be valid \&\s-1CA\s0 certificates. The precise extensions required are described in more detail in the \fB\s-1CERTIFICATE\s0 \s-1EXTENSIONS\s0\fR section of the \fBx509\fR utility. .PP The third operation is to check the trust settings on the root \s-1CA\s0. The root \&\s-1CA\s0 should be trusted for the supplied purpose. For compatibility with previous versions of SSLeay and OpenSSL a certificate with no trust settings is considered to be valid for all purposes. .PP The final operation is to check the validity of the certificate chain. The validity period is checked against the current system time and the notBefore and notAfter dates in the certificate. The certificate signatures are also checked at this point. .PP If all operations complete successfully then certificate is considered valid. If any operation fails then the certificate is not valid. .SH "DIAGNOSTICS" .IX Header "DIAGNOSTICS" When a verify operation fails the output messages can be somewhat cryptic. The general form of the error message is: .PP .Vb 2 \& server.pem: /C=AU/ST=Queensland/O=CryptSoft Pty Ltd/CN=Test CA (1024 bit) \& error 24 at 1 depth lookup:invalid CA certificate .Ve .PP The first line contains the name of the certificate being verified followed by the subject name of the certificate. The second line contains the error number and the depth. The depth is number of the certificate being verified when a problem was detected starting with zero for the certificate being verified itself then 1 for the \s-1CA\s0 that signed the certificate and so on. Finally a text version of the error number is presented. .PP An exhaustive list of the error codes and messages is shown below, this also includes the name of the error code as defined in the header file x509_vfy.h Some of the error codes are defined but never returned: these are described as \*(L"unused\*(R". .IP "\fB0 X509_V_OK: ok\fR" 4 .IX Item "0 X509_V_OK: ok" the operation was successful. .IP "\fB2 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT: unable to get issuer certificate\fR" 4 .IX Item "2 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT: unable to get issuer certificate" the issuer certificate of a looked up certificate could not be found. This normally means the list of trusted certificates is not complete. .IP "\fB3 X509_V_ERR_UNABLE_TO_GET_CRL: unable to get certificate \s-1CRL\s0\fR" 4 .IX Item "3 X509_V_ERR_UNABLE_TO_GET_CRL: unable to get certificate CRL" the \s-1CRL\s0 of a certificate could not be found. .IP "\fB4 X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE: unable to decrypt certificate's signature\fR" 4 .IX Item "4 X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE: unable to decrypt certificate's signature" the certificate signature could not be decrypted. This means that the actual signature value could not be determined rather than it not matching the expected value, this is only meaningful for \s-1RSA\s0 keys. .IP "\fB5 X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE: unable to decrypt \s-1CRL\s0's signature\fR" 4 .IX Item "5 X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE: unable to decrypt CRL's signature" the \s-1CRL\s0 signature could not be decrypted: this means that the actual signature value could not be determined rather than it not matching the expected value. Unused. .IP "\fB6 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY: unable to decode issuer public key\fR" 4 .IX Item "6 X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY: unable to decode issuer public key" the public key in the certificate SubjectPublicKeyInfo could not be read. .IP "\fB7 X509_V_ERR_CERT_SIGNATURE_FAILURE: certificate signature failure\fR" 4 .IX Item "7 X509_V_ERR_CERT_SIGNATURE_FAILURE: certificate signature failure" the signature of the certificate is invalid. .IP "\fB8 X509_V_ERR_CRL_SIGNATURE_FAILURE: \s-1CRL\s0 signature failure\fR" 4 .IX Item "8 X509_V_ERR_CRL_SIGNATURE_FAILURE: CRL signature failure" the signature of the certificate is invalid. .IP "\fB9 X509_V_ERR_CERT_NOT_YET_VALID: certificate is not yet valid\fR" 4 .IX Item "9 X509_V_ERR_CERT_NOT_YET_VALID: certificate is not yet valid" the certificate is not yet valid: the notBefore date is after the current time. .IP "\fB10 X509_V_ERR_CERT_HAS_EXPIRED: certificate has expired\fR" 4 .IX Item "10 X509_V_ERR_CERT_HAS_EXPIRED: certificate has expired" the certificate has expired: that is the notAfter date is before the current time. .IP "\fB11 X509_V_ERR_CRL_NOT_YET_VALID: \s-1CRL\s0 is not yet valid\fR" 4 .IX Item "11 X509_V_ERR_CRL_NOT_YET_VALID: CRL is not yet valid" the \s-1CRL\s0 is not yet valid. .IP "\fB12 X509_V_ERR_CRL_HAS_EXPIRED: \s-1CRL\s0 has expired\fR" 4 .IX Item "12 X509_V_ERR_CRL_HAS_EXPIRED: CRL has expired" the \s-1CRL\s0 has expired. .IP "\fB13 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD: format error in certificate's notBefore field\fR" 4 .IX Item "13 X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD: format error in certificate's notBefore field" the certificate notBefore field contains an invalid time. .IP "\fB14 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD: format error in certificate's notAfter field\fR" 4 .IX Item "14 X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD: format error in certificate's notAfter field" the certificate notAfter field contains an invalid time. .IP "\fB15 X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD: format error in \s-1CRL\s0's lastUpdate field\fR" 4 .IX Item "15 X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD: format error in CRL's lastUpdate field" the \s-1CRL\s0 lastUpdate field contains an invalid time. .IP "\fB16 X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD: format error in \s-1CRL\s0's nextUpdate field\fR" 4 .IX Item "16 X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD: format error in CRL's nextUpdate field" the \s-1CRL\s0 nextUpdate field contains an invalid time. .IP "\fB17 X509_V_ERR_OUT_OF_MEM: out of memory\fR" 4 .IX Item "17 X509_V_ERR_OUT_OF_MEM: out of memory" an error occurred trying to allocate memory. This should never happen. .IP "\fB18 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT: self signed certificate\fR" 4 .IX Item "18 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT: self signed certificate" the passed certificate is self signed and the same certificate cannot be found in the list of trusted certificates. .IP "\fB19 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN: self signed certificate in certificate chain\fR" 4 .IX Item "19 X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN: self signed certificate in certificate chain" the certificate chain could be built up using the untrusted certificates but the root could not be found locally. .IP "\fB20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: unable to get local issuer certificate\fR" 4 .IX Item "20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: unable to get local issuer certificate" the issuer certificate could not be found: this occurs if the issuer certificate of an untrusted certificate cannot be found. .IP "\fB21 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE: unable to verify the first certificate\fR" 4 .IX Item "21 X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE: unable to verify the first certificate" no signatures could be verified because the chain contains only one certificate and it is not self signed. .IP "\fB22 X509_V_ERR_CERT_CHAIN_TOO_LONG: certificate chain too long\fR" 4 .IX Item "22 X509_V_ERR_CERT_CHAIN_TOO_LONG: certificate chain too long" the certificate chain length is greater than the supplied maximum depth. Unused. .IP "\fB23 X509_V_ERR_CERT_REVOKED: certificate revoked\fR" 4 .IX Item "23 X509_V_ERR_CERT_REVOKED: certificate revoked" the certificate has been revoked. .IP "\fB24 X509_V_ERR_INVALID_CA: invalid \s-1CA\s0 certificate\fR" 4 .IX Item "24 X509_V_ERR_INVALID_CA: invalid CA certificate" a \s-1CA\s0 certificate is invalid. Either it is not a \s-1CA\s0 or its extensions are not consistent with the supplied purpose. .IP "\fB25 X509_V_ERR_PATH_LENGTH_EXCEEDED: path length constraint exceeded\fR" 4 .IX Item "25 X509_V_ERR_PATH_LENGTH_EXCEEDED: path length constraint exceeded" the basicConstraints pathlength parameter has been exceeded. .IP "\fB26 X509_V_ERR_INVALID_PURPOSE: unsupported certificate purpose\fR" 4 .IX Item "26 X509_V_ERR_INVALID_PURPOSE: unsupported certificate purpose" the supplied certificate cannot be used for the specified purpose. .IP "\fB27 X509_V_ERR_CERT_UNTRUSTED: certificate not trusted\fR" 4 .IX Item "27 X509_V_ERR_CERT_UNTRUSTED: certificate not trusted" the root \s-1CA\s0 is not marked as trusted for the specified purpose. .IP "\fB28 X509_V_ERR_CERT_REJECTED: certificate rejected\fR" 4 .IX Item "28 X509_V_ERR_CERT_REJECTED: certificate rejected" the root \s-1CA\s0 is marked to reject the specified purpose. .IP "\fB29 X509_V_ERR_SUBJECT_ISSUER_MISMATCH: subject issuer mismatch\fR" 4 .IX Item "29 X509_V_ERR_SUBJECT_ISSUER_MISMATCH: subject issuer mismatch" the current candidate issuer certificate was rejected because its subject name did not match the issuer name of the current certificate. Only displayed when the \fB\-issuer_checks\fR option is set. .IP "\fB30 X509_V_ERR_AKID_SKID_MISMATCH: authority and subject key identifier mismatch\fR" 4 .IX Item "30 X509_V_ERR_AKID_SKID_MISMATCH: authority and subject key identifier mismatch" the current candidate issuer certificate was rejected because its subject key identifier was present and did not match the authority key identifier current certificate. Only displayed when the \fB\-issuer_checks\fR option is set. .IP "\fB31 X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH: authority and issuer serial number mismatch\fR" 4 .IX Item "31 X509_V_ERR_AKID_ISSUER_SERIAL_MISMATCH: authority and issuer serial number mismatch" the current candidate issuer certificate was rejected because its issuer name and serial number was present and did not match the authority key identifier of the current certificate. Only displayed when the \fB\-issuer_checks\fR option is set. .IP "\fB32 X509_V_ERR_KEYUSAGE_NO_CERTSIGN:key usage does not include certificate signing\fR" 4 .IX Item "32 X509_V_ERR_KEYUSAGE_NO_CERTSIGN:key usage does not include certificate signing" the current candidate issuer certificate was rejected because its keyUsage extension does not permit certificate signing. .IP "\fB50 X509_V_ERR_APPLICATION_VERIFICATION: application verification failure\fR" 4 .IX Item "50 X509_V_ERR_APPLICATION_VERIFICATION: application verification failure" an application specific error. Unused. .SH "BUGS" .IX Header "BUGS" Although the issuer checks are a considerable improvement over the old technique they still suffer from limitations in the underlying X509_LOOKUP \s-1API\s0. One consequence of this is that trusted certificates with matching subject name must either appear in a file (as specified by the \&\fB\-CAfile\fR option) or a directory (as specified by \fB\-CApath\fR. If they occur in both then only the certificates in the file will be recognised. .PP Previous versions of OpenSSL assume certificates with matching subject name are identical and mishandled them. .PP Previous versions of this documentation swapped the meaning of the \&\fBX509_V_ERR_UNABLE_TO_GET_ISSUER_CERT\fR and \&\fB20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY\fR error codes. .SH "SEE ALSO" .IX Header "SEE ALSO" \&\fIx509\fR\|(1) .SH "HISTORY" .IX Header "HISTORY" The \-no_alt_chains options was first added to OpenSSL 1.0.2b.