| =pod |
| |
| =head1 NAME |
| |
| X509_VERIFY_PARAM_set_flags, X509_VERIFY_PARAM_clear_flags, X509_VERIFY_PARAM_get_flags, X509_VERIFY_PARAM_set_purpose, X509_VERIFY_PARAM_set_trust, X509_VERIFY_PARAM_set_depth, X509_VERIFY_PARAM_get_depth, X509_VERIFY_PARAM_set_time, X509_VERIFY_PARAM_add0_policy, X509_VERIFY_PARAM_set1_policies - X509 verification parameters |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/x509_vfy.h> |
| |
| int X509_VERIFY_PARAM_set_flags(X509_VERIFY_PARAM *param, unsigned long flags); |
| int X509_VERIFY_PARAM_clear_flags(X509_VERIFY_PARAM *param, |
| unsigned long flags); |
| unsigned long X509_VERIFY_PARAM_get_flags(X509_VERIFY_PARAM *param); |
| |
| int X509_VERIFY_PARAM_set_purpose(X509_VERIFY_PARAM *param, int purpose); |
| int X509_VERIFY_PARAM_set_trust(X509_VERIFY_PARAM *param, int trust); |
| |
| void X509_VERIFY_PARAM_set_time(X509_VERIFY_PARAM *param, time_t t); |
| |
| int X509_VERIFY_PARAM_add0_policy(X509_VERIFY_PARAM *param, |
| ASN1_OBJECT *policy); |
| int X509_VERIFY_PARAM_set1_policies(X509_VERIFY_PARAM *param, |
| STACK_OF(ASN1_OBJECT) *policies); |
| |
| void X509_VERIFY_PARAM_set_depth(X509_VERIFY_PARAM *param, int depth); |
| int X509_VERIFY_PARAM_get_depth(const X509_VERIFY_PARAM *param); |
| |
| =head1 DESCRIPTION |
| |
| These functions manipulate the B<X509_VERIFY_PARAM> structure associated with |
| a certificate verification operation. |
| |
| The X509_VERIFY_PARAM_set_flags() function sets the flags in B<param> by oring |
| it with B<flags>. See the B<VERIFICATION FLAGS> section for a complete |
| description of values the B<flags> parameter can take. |
| |
| X509_VERIFY_PARAM_get_flags() returns the flags in B<param>. |
| |
| X509_VERIFY_PARAM_clear_flags() clears the flags B<flags> in B<param>. |
| |
| X509_VERIFY_PARAM_set_purpose() sets the verification purpose in B<param> |
| to B<purpose>. This determines the acceptable purpose of the certificate |
| chain, for example SSL client or SSL server. |
| |
| X509_VERIFY_PARAM_set_trust() sets the trust setting in B<param> to |
| B<trust>. |
| |
| X509_VERIFY_PARAM_set_time() sets the verification time in B<param> to |
| B<t>. Normally the current time is used. |
| |
| X509_VERIFY_PARAM_add0_policy() enables policy checking (it is disabled |
| by default) and adds B<policy> to the acceptable policy set. |
| |
| X509_VERIFY_PARAM_set1_policies() enables policy checking (it is disabled |
| by default) and sets the acceptable policy set to B<policies>. Any existing |
| policy set is cleared. The B<policies> parameter can be B<NULL> to clear |
| an existing policy set. |
| |
| X509_VERIFY_PARAM_set_depth() sets the maximum verification depth to B<depth>. |
| That is the maximum number of untrusted CA certificates that can appear in a |
| chain. |
| |
| =head1 RETURN VALUES |
| |
| X509_VERIFY_PARAM_set_flags(), X509_VERIFY_PARAM_clear_flags(), |
| X509_VERIFY_PARAM_set_purpose(), X509_VERIFY_PARAM_set_trust(), |
| X509_VERIFY_PARAM_add0_policy() and X509_VERIFY_PARAM_set1_policies() return 1 |
| for success and 0 for failure. |
| |
| X509_VERIFY_PARAM_get_flags() returns the current verification flags. |
| |
| X509_VERIFY_PARAM_set_time() and X509_VERIFY_PARAM_set_depth() do not return |
| values. |
| |
| X509_VERIFY_PARAM_get_depth() returns the current verification depth. |
| |
| =head1 VERIFICATION FLAGS |
| |
| The verification flags consists of zero or more of the following flags |
| ored together. |
| |
| B<X509_V_FLAG_CRL_CHECK> enables CRL checking for the certificate chain leaf |
| certificate. An error occurs if a suitable CRL cannot be found. |
| |
| B<X509_V_FLAG_CRL_CHECK_ALL> enables CRL checking for the entire certificate |
| chain. |
| |
| B<X509_V_FLAG_IGNORE_CRITICAL> disabled critical extension checking. By default |
| any unhandled critical extensions in certificates or (if checked) CRLs results |
| in a fatal error. If this flag is set unhandled critical extensions are |
| ignored. B<WARNING> setting this option for anything other than debugging |
| purposes can be a security risk. Finer control over which extensions are |
| supported can be performed in the verification callback. |
| |
| THe B<X509_V_FLAG_X509_STRICT> flag disables workarounds for some broken |
| certificates and makes the verification strictly apply B<X509> rules. |
| |
| B<X509_V_FLAG_ALLOW_PROXY_CERTS> enables proxy certificate verification. |
| |
| B<X509_V_FLAG_POLICY_CHECK> enables certificate policy checking, by default |
| no policy checking is peformed. Additional information is sent to the |
| verification callback relating to policy checking. |
| |
| B<X509_V_FLAG_EXPLICIT_POLICY>, B<X509_V_FLAG_INHIBIT_ANY> and |
| B<X509_V_FLAG_INHIBIT_MAP> set the B<require explicit policy>, B<inhibit any |
| policy> and B<inhibit policy mapping> flags respectively as defined in |
| B<RFC3280>. Policy checking is automatically enabled if any of these flags |
| are set. |
| |
| If B<X509_V_FLAG_NOTIFY_POLICY> is set and the policy checking is successful |
| a special status code is set to the verification callback. This permits it |
| to examine the valid policy tree and perform additional checks or simply |
| log it for debugging purposes. |
| |
| By default some additional features such as indirect CRLs and CRLs signed by |
| different keys are disabled. If B<X509_V_FLAG_EXTENDED_CRL_SUPPORT> is set |
| they are enabled. |
| |
| If B<X509_V_FLAG_USE_DELTAS> ise set delta CRLs (if present) are used to |
| determine certificate status. If not set deltas are ignored. |
| |
| B<X509_V_FLAG_CHECK_SS_SIGNATURE> enables checking of the root CA self signed |
| cerificate signature. By default this check is disabled because it doesn't |
| add any additional security but in some cases applications might want to |
| check the signature anyway. A side effect of not checking the root CA |
| signature is that disabled or unsupported message digests on the root CA |
| are not treated as fatal errors. |
| |
| The B<X509_V_FLAG_CB_ISSUER_CHECK> flag enables debugging of certificate |
| issuer checks. It is B<not> needed unless you are logging certificate |
| verification. If this flag is set then additional status codes will be sent |
| to the verification callback and it B<must> be prepared to handle such cases |
| without assuming they are hard errors. |
| |
| The B<X509_V_FLAG_NO_ALT_CHAINS> flag suppresses checking for alternative |
| chains. By default, 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 flag set the behaviour |
| will match that of OpenSSL versions prior to 1.0.1n and 1.0.2b. |
| |
| =head1 NOTES |
| |
| The above functions should be used to manipulate verification parameters |
| instead of legacy functions which work in specific structures such as |
| X509_STORE_CTX_set_flags(). |
| |
| =head1 BUGS |
| |
| Delta CRL checking is currently primitive. Only a single delta can be used and |
| (partly due to limitations of B<X509_STORE>) constructed CRLs are not |
| maintained. |
| |
| If CRLs checking is enable CRLs are expected to be available in the |
| corresponding B<X509_STORE> structure. No attempt is made to download |
| CRLs from the CRL distribution points extension. |
| |
| =head1 EXAMPLE |
| |
| Enable CRL checking when performing certificate verification during SSL |
| connections associated with an B<SSL_CTX> structure B<ctx>: |
| |
| X509_VERIFY_PARAM *param; |
| param = X509_VERIFY_PARAM_new(); |
| X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK); |
| SSL_CTX_set1_param(ctx, param); |
| X509_VERIFY_PARAM_free(param); |
| |
| =head1 SEE ALSO |
| |
| L<X509_verify_cert(3)|X509_verify_cert(3)> |
| |
| =head1 HISTORY |
| |
| The B<X509_V_FLAG_NO_ALT_CHAINS> flag was added in OpenSSL 1.0.1n and 1.0.2b |
| |
| =cut |
