(PHP 4 >= 4.0.6, PHP 5)
openssl_x509_checkpurpose — Verifies if a certificate can be used for a particular purpose
openssl_x509_checkpurpose() examines a certificate to see if it can be used for the specified purpose.
The examined certificate.
openssl_x509_checkpurpose() purposes Constant Description X509_PURPOSE_SSL_CLIENT Can the certificate be used for the client side of an SSL connection? X509_PURPOSE_SSL_SERVER Can the certificate be used for the server side of an SSL connection? X509_PURPOSE_NS_SSL_SERVER Can the cert be used for Netscape SSL server? X509_PURPOSE_SMIME_SIGN Can the cert be used to sign S/MIME email? X509_PURPOSE_SMIME_ENCRYPT Can the cert be used to encrypt S/MIME email? X509_PURPOSE_CRL_SIGN Can the cert be used to sign a certificate revocation list (CRL)? X509_PURPOSE_ANY Can the cert be used for Any/All purposes?
cainfo should be an array of trusted CA files/dirs as described in Certificate Verification.
If specified, this should be the name of a PEM encoded file holding certificates that can be used to help verify the certificate, although no trust is placed in the certificates that come from that file.
Returns TRUE if the certificate can be used for the intended purpose, FALSE if it cannot, or -1 on error.