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verify(1)                           OpenSSL                          verify(1)


       openssl-verify, verify - Utility to verify certificates


       openssl verify [-help] [-CAfile file] [-CApath directory] [-no-CAfile]
       [-no-CApath] [-allow_proxy_certs] [-attime timestamp] [-check_ss_sig]
       [-CRLfile file] [-crl_download] [-crl_check] [-crl_check_all] [-engine
       id] [-explicit_policy] [-extended_crl] [-ignore_critical]
       [-inhibit_any] [-inhibit_map] [-nameopt option] [-no_check_time]
       [-partial_chain] [-policy arg] [-policy_check] [-policy_print]
       [-purpose purpose] [-suiteB_128] [-suiteB_128_only] [-suiteB_192]
       [-trusted_first] [-no_alt_chains] [-untrusted file] [-trusted file]
       [-use_deltas] [-verbose] [-auth_level level] [-verify_depth num]
       [-verify_email email] [-verify_hostname hostname] [-verify_ip ip]
       [-verify_name name] [-x509_strict] [-show_chain] [-] [certificates]


       The verify command verifies certificate chains.


           Print out a usage message.

       -CAfile file
           A file of trusted certificates.  The file should contain one or
           more certificates in PEM format.

       -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 ("hash" is the hashed certificate subject name: see the -hash
           option of the x509 utility). Under Unix the c_rehash script will
           automatically create symbolic links to a directory of certificates.

           Do not load the trusted CA certificates from the default file

           Do not load the trusted CA certificates from the default directory

           Allow the verification of proxy certificates.

       -attime timestamp
           Perform validation checks using time specified by timestamp and not
           current system time. timestamp is the number of seconds since
           01.01.1970 (UNIX time).

           Verify the signature of the last certificate in a chain if the
           certificate is supposedly self-signed.  This is prohibited and will
           result in an error if it is a non-conforming CA certificate with
           key usage restrictions not including the keyCertSign bit.  This
           verification is disabled by default because it doesn't add any

       -CRLfile file
           The file should contain one or more CRLs in PEM format.  This
           option can be specified more than once to include CRLs from
           multiple files.

           Attempt to download CRL information for this certificate.

           Checks end entity certificate validity by attempting to look up a
           valid CRL.  If a valid CRL cannot be found an error occurs.

           Checks the validity of all certificates in the chain by attempting
           to look up valid CRLs.

       -engine id
           Specifying an engine verify(1) to attempt to load the
           specified engine.  The engine will then be set as the default for
           all its supported algorithms.  If you want to load certificates or
           CRLs that require engine support via any of the -trusted,
           -untrusted or -CRLfile options, the -engine option must be
           specified before those options.

           Set policy variable require-explicit-policy (see RFC5280).

           Enable extended CRL features such as indirect CRLs and alternate
           CRL signing keys.

           Normally if an unhandled critical extension is present which is not
           supported by OpenSSL the certificate is rejected (as required by
           RFC5280).  If this option is set critical extensions are ignored.

           Set policy variable inhibit-any-policy (see RFC5280).

           Set policy variable inhibit-policy-mapping (see RFC5280).

       -nameopt option
           Option which determines how the subject or issuer names are
           displayed. The option argument can be a single option or multiple
           options separated by commas.  Alternatively the -nameopt switch may
           be used more than once to set multiple options. See the x509(1)
           manual page for details.

           This option suppresses checking the validity period of certificates
           and CRLs against the current time. If option -attime timestamp is
           used to specify a verification time, the check is not suppressed.

           Allow verification to succeed even if a complete chain cannot be
           built to a self-signed trust-anchor, provided it is possible to
           construct a chain to a trusted certificate that might not be self-

       -policy arg
           Enable policy processing and add arg to the user-initial-policy-set
           (see RFC5280). The policy arg can be an object name an OID in
           numeric form.  This argument can appear more than once.

           Enables certificate policy processing.

           Print out diagnostics related to policy processing.

       -purpose purpose
           The intended use for the certificate. If this option is not
           specified, verify will not consider certificate purpose during
           chain verification.  Currently accepted uses are sslclient,
           sslserver, nssslserver, smimesign, smimeencrypt. See the VERIFY
           OPERATION section for more information.

       -suiteB_128_only, -suiteB_128, -suiteB_192
           Enable the Suite B mode operation at 128 bit Level of Security, 128
           bit or 192 bit, or only 192 bit Level of Security respectively.
           See RFC6460 for details. In particular the supported signature
           algorithms are reduced to support only ECDSA and SHA256 or SHA384
           and only the elliptic curves P-256 and P-384.

           When constructing the certificate chain, use the trusted
           certificates specified via -CAfile, -CApath or -trusted before any
           certificates specified via -untrusted.  This can be useful in
           environments with Bridge or Cross-Certified CAs.  As of OpenSSL
           1.1.0 this option is on by default and cannot be disabled.

           By default, unless -trusted_first is specified, when building a
           certificate chain, if the first certificate chain found is not
           trusted, then OpenSSL will attempt to replace untrusted issuer
           certificates with certificates from the trust store to see if an
           alternative chain can be found that is trusted.  As of OpenSSL
           1.1.0, with -trusted_first always on, this option has no effect.

       -untrusted file
           A file of additional untrusted certificates (intermediate issuer
           CAs) used to construct a certificate chain from the subject
           certificate to a trust-anchor.  The file should contain one or more
           certificates in PEM format.  This option can be specified more than
           once to include untrusted certificates from multiple files.

       -trusted file
           A file of trusted certificates, which must be self-signed, unless
           the -partial_chain option is specified.  The file contains one or
           more certificates in PEM format.  With this option, no additional
           (e.g., default) certificate lists are consulted.  That is, the only
           trust-anchors are those listed in file.  This option can be
           specified more than once to include trusted certificates from
           multiple files.  This option implies the -no-CAfile and -no-CApath
           options.  This option cannot be used in combination with either of
           the -CAfile or -CApath options.

           Enable support for delta CRLs.

           Print extra information about the operations being performed.

       -auth_level level
           Set the certificate chain authentication security level to level.
           The authentication security level determines the acceptable
           signature and public key strength when verifying certificate
           chains.  For a certificate chain to validate, the public keys of
           all the certificates must meet the specified security level.  The
           signature algorithm security level is enforced for all the
           certificates in the chain except for the chain's trust anchor,
           which is either directly trusted or validated by means other than
           its signature.  See SSL_CTX_set_security_level(3) for the
           definitions of the available levels.  The default security level is
           -1, or "not set".  At security level 0 or lower all algorithms are
           acceptable.  Security level 1 requires at least 80-bit-equivalent
           security and is broadly interoperable, though it will, for example,
           reject MD5 signatures or RSA keys shorter than 1024 bits.

       -verify_depth num
           Limit the certificate chain to num intermediate CA certificates.  A
           maximal depth chain can have up to num+2 certificates, since
           neither the end-entity certificate nor the trust-anchor certificate
           count against the -verify_depth limit.

       -verify_email email
           Verify if the email matches the email address in Subject
           Alternative Name or the email in the subject Distinguished Name.

       -verify_hostname hostname
           Verify if the hostname matches DNS name in Subject Alternative Name
           or Common Name in the subject certificate.

       -verify_ip ip
           Verify if the ip matches the IP address in Subject Alternative Name
           of the subject certificate.

       -verify_name name
           Use default verification policies like trust model and required
           certificate policies identified by name.  The trust model
           determines which auxiliary trust or reject OIDs are applicable to
           verifying the given certificate chain.  See the -addtrust and
           -addreject options of the x509(1) command-line utility.  Supported
           policy names include: default, pkcs7, smime_sign, ssl_client,
           ssl_server.  These mimics the combinations of purpose and trust
           settings used in SSL, CMS and S/MIME.  As of OpenSSL 1.1.0, the
           trust model is inferred from the purpose when not specified, so the
           -verify_name options are functionally equivalent to the
           corresponding -purpose settings.

           For strict X.509 compliance, disable non-compliant workarounds for
           broken certificates.

           Display information about the certificate chain that has been built
           (if successful). Certificates in the chain that came from the
           untrusted list will be flagged as "untrusted".

       -   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 -.

           One or more certificates to verify. If no certificates are given,
           verify will attempt to read a certificate from standard input.
           Certificates must be in PEM format.


       The verify program uses the same functions as the internal SSL and
       S/MIME verification, therefore, this description applies to these
       verify operations too.

       There is one crucial difference between the verify operations performed
       by the verify 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.

       The verify operation consists of a number of separate steps.

       Firstly a certificate chain is built up starting from the supplied
       certificate and ending in the root CA.  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 CA.

       The process of 'looking up the issuers certificate' itself involves a
       number of steps.  After 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.

       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 CA 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.

       The second operation is to check every untrusted certificate's
       extensions for consistency with the supplied purpose. If the -purpose
       option is not included then no checks are done. The supplied or "leaf"
       certificate must have extensions compatible with the supplied purpose
       and all other certificates must also be valid CA certificates. The
       precise extensions required are described in more detail in the
       CERTIFICATE EXTENSIONS section of the x509 utility.

       The third operation is to check the trust settings on the root CA. The
       root CA should be trusted for the supplied purpose.  For compatibility
       with previous versions of OpenSSL, a certificate with no trust settings
       is considered to be valid for all purposes.

       The final operation is to check the validity of the certificate chain.
       For each element in the chain, including the root CA certificate, the
       validity period as specified by the "notBefore" and "notAfter" fields
       is checked against the current system time.  The -attime flag may be
       used to use a reference time other than "now."  The certificate
       signature is checked as well (except for the signature of the typically
       self-signed root CA certificate, which is verified only if the
       -check_ss_sig option is given).

       If all operations complete successfully then certificate is considered
       valid. If any operation fails then the certificate is not valid.


       When a verify operation fails the output messages can be somewhat
       cryptic. The general form of the error message is:

        server.pem: /C=AU/ST=Queensland/O=CryptSoft Pty Ltd/CN=Test CA (1024 bit)
        error 24 at 1 depth lookup:invalid CA certificate

       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 CA that
       signed the certificate and so on. Finally a text version of the error
       number is presented.

       A partial 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 "unused".

           The operation was successful.

           Unspecified error; should not happen.

           The issuer certificate of a looked up certificate could not be
           found. This normally means the list of trusted certificates is not

           The CRL of a certificate could not be found.

           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 RSA

           The CRL 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.

           The public key in the certificate SubjectPublicKeyInfo could not be

           The signature of the certificate is invalid.

           The signature of the certificate is invalid.

           The certificate is not yet valid: the notBefore date is after the
           current time.

           The certificate has expired: that is the notAfter date is before
           the current time.

           The CRL is not yet valid.

           The CRL has expired.

           The certificate notBefore field contains an invalid time.

           The certificate notAfter field contains an invalid time.

           The CRL lastUpdate field contains an invalid time.

           The CRL nextUpdate field contains an invalid time.

           An error occurred trying to allocate memory. This should never

           The passed certificate is self-signed and the same certificate
           cannot be found in the list of trusted certificates.

           The certificate chain could be built up using the untrusted
           certificates but the root could not be found locally.

           The issuer certificate could not be found: this occurs if the
           issuer certificate of an untrusted certificate cannot be found.

           No signatures could be verified because the chain contains only one
           certificate and it is not self signed.

           The certificate chain length is greater than the supplied maximum
           depth. Unused.

           The certificate has been revoked.

           A CA certificate is invalid. Either it is not a CA or its
           extensions are not consistent with the supplied purpose.

           The basicConstraints pathlength parameter has been exceeded.

           The supplied certificate cannot be used for the specified purpose.

           The root CA is not marked as trusted for the specified purpose.

           The root CA is marked to reject the specified purpose.

           Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
           -issuer_checks option.

           Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
           -issuer_checks option.

           Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
           -issuer_checks option.

           Not used as of OpenSSL 1.1.0 as a result of the deprecation of the
           -issuer_checks option.

           Unable to get CRL issuer certificate.

           Unhandled critical extension.

           Key usage does not include CRL signing.

           Unhandled critical CRL extension.

           Invalid non-CA certificate has CA markings.

           Proxy path length constraint exceeded.

           Proxy certificate subject is invalid.  It MUST be the same as the
           issuer with a single CN component added.

           Key usage does not include digital signature.

           Proxy certificates not allowed, please use -allow_proxy_certs.

           Invalid or inconsistent certificate extension.

           Invalid or inconsistent certificate policy extension.

           No explicit policy.

           Different CRL scope.

           Unsupported extension feature.

           RFC 3779 resource not subset of parent's resources.

           Permitted subtree violation.

           Excluded subtree violation.

           Name constraints minimum and maximum not supported.

           Application verification failure. Unused.

           Unsupported name constraint type.

           Unsupported or invalid name constraint syntax.

           Unsupported or invalid name syntax.

           CRL path validation error.

           Path loop.

           Suite B: certificate version invalid.

           Suite B: invalid public key algorithm.

           Suite B: invalid ECC curve.

           Suite B: invalid signature algorithm.

           Suite B: curve not allowed for this LOS.

           Suite B: cannot sign P-384 with P-256.

           Hostname mismatch.

           Email address mismatch.

           IP address mismatch.

           DANE TLSA authentication is enabled, but no TLSA records matched
           the certificate chain.  This error is only possible in s_client(1).

           EE certificate key too weak.

           CA certificate key too weak.

           CA signature digest algorithm too weak.

           nvalid certificate verification context.

           Issuer certificate lookup error.

           Certificate Transparency required, but no valid SCTs found.

           Proxy subject name violation.

           Returned by the verify callback to indicate an OCSP verification is

           Returned by the verify callback to indicate OCSP verification

           Returned by the verify callback to indicate that the certificate is
           not recognized by the OCSP responder.


       Although the issuer checks are a considerable improvement over the old
       technique they still suffer from limitations in the underlying
       X509_LOOKUP API. One consequence of this is that trusted certificates
       with matching subject name must either appear in a file (as specified
       by the -CAfile option) or a directory (as specified by -CApath). If
       they occur in both then only the certificates in the file will be

       Previous versions of OpenSSL assume certificates with matching subject
       name are identical and mishandled them.

       Previous versions of this documentation swapped the meaning of the




       The -show_chain option was added in OpenSSL 1.1.0.

       The -issuer_checks option is deprecated as of OpenSSL 1.1.0 and is
       silently ignored.


       Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (the "License").  You may not use
       this file except in compliance with the License.  You can obtain a copy
       in the file LICENSE in the source distribution or at

1.1.1i                            2020-12-08                         verify(1)

openssl 1.1.1i - Generated Wed Dec 9 14:54:12 CST 2020
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