=pod =head1 NAME X509_STORE_CTX_get_error, X509_STORE_CTX_set_error, X509_STORE_CTX_get_error_depth, X509_STORE_CTX_set_error_depth, X509_STORE_CTX_get_current_cert, X509_STORE_CTX_set_current_cert, X509_STORE_CTX_get0_cert, X509_STORE_CTX_get1_chain, X509_verify_cert_error_string - get or set certificate verification status information =head1 SYNOPSIS #include int X509_STORE_CTX_get_error(const X509_STORE_CTX *ctx); void X509_STORE_CTX_set_error(X509_STORE_CTX *ctx, int s); int X509_STORE_CTX_get_error_depth(const X509_STORE_CTX *ctx); void X509_STORE_CTX_set_error_depth(X509_STORE_CTX *ctx, int depth); X509 *X509_STORE_CTX_get_current_cert(const X509_STORE_CTX *ctx); void X509_STORE_CTX_set_current_cert(X509_STORE_CTX *ctx, X509 *x); X509 *X509_STORE_CTX_get0_cert(const X509_STORE_CTX *ctx); STACK_OF(X509) *X509_STORE_CTX_get1_chain(const X509_STORE_CTX *ctx); const char *X509_verify_cert_error_string(long n); =head1 DESCRIPTION These functions are typically called after certificate or chain verification using L or L has indicated an error or in a verification callback to determine the nature of an error. X509_STORE_CTX_get_error() returns the error code of I. See the L section for a full description of all error codes. It may return a code != X509_V_OK even if X509_verify_cert() did not indicate an error, likely because a verification callback function has waived the error. X509_STORE_CTX_set_error() sets the error code of I to I. For example it might be used in a verification callback to set an error based on additional checks. X509_STORE_CTX_get_error_depth() returns the I of the error. This is a nonnegative integer representing where in the certificate chain the error occurred. If it is zero it occurred in the end entity certificate, one if it is the certificate which signed the end entity certificate and so on. X509_STORE_CTX_set_error_depth() sets the error I. This can be used in combination with X509_STORE_CTX_set_error() to set the depth at which an error condition was detected. X509_STORE_CTX_get_current_cert() returns the certificate in I which caused the error or NULL if no certificate is relevant. X509_STORE_CTX_set_current_cert() sets the certificate I in I which caused the error. This value is not intended to remain valid for very long, and remains owned by the caller. It may be examined by a verification callback invoked to handle each error encountered during chain verification and is no longer required after such a callback. If a callback wishes the save the certificate for use after it returns, it needs to increment its reference count via L. Once such a I certificate is no longer needed it can be freed with L. X509_STORE_CTX_get0_cert() retrieves an internal pointer to the certificate being verified by the I. X509_STORE_CTX_get1_chain() returns a complete validate chain if a previous verification is successful. Otherwise the returned chain may be incomplete or invalid. The returned chain persists after the I structure is freed. When it is no longer needed it should be free up using: sk_X509_pop_free(chain, X509_free); X509_verify_cert_error_string() returns a human readable error string for verification error I. =head1 RETURN VALUES X509_STORE_CTX_get_error() returns B or an error code. X509_STORE_CTX_get_error_depth() returns a nonnegative error depth. X509_STORE_CTX_get_current_cert() returns the certificate which caused the error or NULL if no certificate is relevant to the error. X509_verify_cert_error_string() returns a human readable error string for verification error I. =head1 ERROR CODES A list of error codes and messages is shown below. Some of the error codes are defined but currently never returned: these are described as "unused". =over 4 =item B The operation was successful. =item B Unspecified error; should not happen. =item B The issuer certificate of a locally looked up certificate could not be found. This normally means the list of trusted certificates is not complete. To allow any certificate (not only a self-signed one) in the trust store to terminate the chain the B flag may be set. =item B The CRL of a certificate could not be found. =item B 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 keys. =item B 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. =item B The public key in the certificate C field could not be read. =item B The signature of the certificate is invalid. =item B The signature of the certificate is invalid. =item B The certificate is not yet valid: the C date is after the current time. =item B The certificate has expired: that is the C date is before the current time. =item B The CRL is not yet valid. =item B The CRL has expired. =item B The certificate C field contains an invalid time. =item B The certificate C field contains an invalid time. =item B The CRL B field contains an invalid time. =item B The CRL C field contains an invalid time. =item B An error occurred trying to allocate memory. =item B The passed certificate is self-signed and the same certificate cannot be found in the list of trusted certificates. =item B The certificate chain could be built up using the untrusted certificates but no suitable trust anchor (which typically is a self-signed root certificate) could be found in the trust store. =item B The issuer certificate could not be found: this occurs if the issuer certificate of an untrusted certificate cannot be found. =item B No signatures could be verified because the chain contains only one certificate and it is not self-signed and the B flag is not set. =item B The certificate chain length is greater than the supplied maximum depth. Unused. =item B The certificate has been revoked. =item B A CA certificate is invalid. Either it is not a CA or its extensions are not consistent with the supplied purpose. =item B The basicConstraints path-length parameter has been exceeded. =item B The target certificate cannot be used for the specified purpose. =item B The root CA is not marked as trusted for the specified purpose. =item B The root CA is marked to reject the specified purpose. =item B The current candidate issuer certificate was rejected because its subject name did not match the issuer name of the current certificate. =item B The current candidate issuer certificate was rejected because its subject key identifier was present and did not match the authority key identifier current certificate. Not used as of OpenSSL 1.1.0. =item B 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. Not used as of OpenSSL 1.1.0. =item B The current candidate issuer certificate was rejected because its C extension does not permit certificate signing. Not used as of OpenSSL 1.1.0. =item B A certificate extension had an invalid value (for example an incorrect encoding) or some value inconsistent with other extensions. =item B A certificate policies extension had an invalid value (for example an incorrect encoding) or some value inconsistent with other extensions. This error only occurs if policy processing is enabled. =item B The verification flags were set to require and explicit policy but none was present. =item B The only CRLs that could be found did not match the scope of the certificate. =item B Some feature of a certificate extension is not supported. Unused. =item B A name constraint violation occurred in the permitted subtrees. =item B A name constraint violation occurred in the excluded subtrees. =item B A certificate name constraints extension included a minimum or maximum field: this is not supported. =item B An unsupported name constraint type was encountered. OpenSSL currently only supports directory name, DNS name, email and URI types. =item B The format of the name constraint is not recognised: for example an email address format of a form not mentioned in RFC3280. This could be caused by a garbage extension or some new feature not currently supported. =item B An error occurred when attempting to verify the CRL path. This error can only happen if extended CRL checking is enabled. =item B An application specific error. This will never be returned unless explicitly set by an application callback. =item B Unable to get CRL issuer certificate. =item B Unhandled critical extension. =item B Key usage does not include CRL signing. =item B Unhandled critical CRL extension. =item B Invalid non-CA certificate has CA markings. =item B Proxy path length constraint exceeded. =item B Key usage does not include digital signature, and therefore cannot sign certificates. =item B Proxy certificates not allowed unless the B flag is set. =item B See RFC 3779 for details. =item B Unsupported or invalid name syntax. =item B Path loop. =item B Hostname mismatch. =item B Email address mismatch. =item B IP address mismatch. =item B DANE TLSA authentication is enabled, but no TLSA records matched the certificate chain. This error is only possible in L. =item B EE certificate key too weak. =item B CA certificate key too weak. =item B CA signature digest algorithm too weak. =item B Invalid certificate verification context. =item B Issuer certificate lookup error. =item B Certificate Transparency required, but no valid SCTs found. =item B Proxy subject name violation. =item B Returned by the verify callback to indicate an OCSP verification is needed. =item B Returned by the verify callback to indicate OCSP verification failed. =item B Returned by the verify callback to indicate that the certificate is not recognized by the OCSP responder. =item B<509_V_ERROR_NO_ISSUER_PUBLI_KEY, issuer certificate doesn't have a public key> The issuer certificate does not have a public key. =item B The issuer's public key is not of the type required by the signature in the subject's certificate. =back =head1 NOTES The above functions should be used instead of directly referencing the fields in the B structure. In versions of OpenSSL before 1.0 the current certificate returned by X509_STORE_CTX_get_current_cert() was never NULL. Applications should check the return value before printing out any debugging information relating to the current certificate. If an unrecognised error code is passed to X509_verify_cert_error_string() the numerical value of the unknown code is returned in a static buffer. This is not thread safe but will never happen unless an invalid code is passed. =head1 SEE ALSO L, L, L, L. =head1 COPYRIGHT Copyright 2009-2021 The OpenSSL Project Authors. All Rights Reserved. Licensed under the Apache License 2.0 (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 L. =cut