openssl_x509_verify

(PHP 7 >= 7.4.0, PHP 8)

openssl_x509_verifyVerifies digital signature of x509 certificate against a public key

Description

openssl_x509_verify(OpenSSLCertificate|string $certificate, OpenSSLAsymmetricKey|OpenSSLCertificate|array|string $public_key): int

openssl_x509_verify() verifies that the certificate certificate was signed by the private key corresponding to public key public_key.

Parameters

x509

See Key/Certificate parameters for a list of valid values.

public_key

OpenSSLAsymmetricKey - a key, returned by openssl_get_publickey()

string - a PEM formatted key (e.g. -----BEGIN PUBLIC KEY----- MIIBCgK...)

Return Values

Returns 1 if the signature is correct, 0 if it is incorrect, and -1 on error.

Changelog

Version Description
8.0.0 certificate accepts an OpenSSLCertificate instance now; previously, a resource of type OpenSSL X.509 was accepted.
8.0.0 public_key accepts an OpenSSLAsymmetricKey or OpenSSLCertificate instance now; previously, a resource of type OpenSSL key or OpenSSL X.509 was accepted.

Examples

Example #1 openssl_x509_verify() example

<?php$hostname = "news.php.net";$ssloptions = array(    "capture_peer_cert" => true,     "capture_peer_cert_chain" => true,     "allow_self_signed"=> false,     "CN_match" => $hostname,    "verify_peer" => true,    "SNI_enabled" => true,    "SNI_server_name" => $hostname,); $ctx = stream_context_create( array("ssl" => $ssloptions) );$result = stream_socket_client("ssl://$hostname:443", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $ctx);$cont = stream_context_get_params($result);$x509 = $cont["options"]["ssl"]["peer_certificate"];$certparsed = openssl_x509_parse($x509);foreach($cont["options"]["ssl"]["peer_certificate_chain"] as $chaincert){    $chainparsed = openssl_x509_parse($chaincert);    $chain_public_key = openssl_get_publickey($chaincert);    $r = openssl_x509_verify($x509, $chain_public_key);       if ($r==1)    {        echo $certparsed['subject']['CN'];        echo " was digitally signed by ";        echo $chainparsed['subject']['CN']."\n";    }}?>

See Also