Php/docs/function.openssl-x509-verify

• PHP Manual
• OpenSSL Functions
• Verifies digital signature of x509 certificate against a public key

openssl_x509_verify

(PHP 7 >= 7.4.0)

openssl_x509_verify — Verifies digital signature of x509 certificate against a public key

Description

openssl_x509_verify ( mixed $x509 , mixed $pub_key_id ) : int

openssl_x509_verify() verifies that the x509 certificate was signed by the private key corresponding to public key pub_key_id.

Parameters

x509

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

pub_key_id

resource - a key, returned by openssl_get_publickey()

string - a PEM formatted key, example, "-----BEGIN PUBLIC KEY----- MIIBCgK..."

Return Values

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

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

• openssl_verify() - Verify signature
• openssl_get_publickey() - Alias of openssl_pkey_get_public