openssl_verify

(PHP 4 >= 4.0.4, PHP 5)

openssl_verify -- Verify signature

Description

int openssl_verify ( string data, string signature, mixed pub_key_id)

Warning

This function is EXPERIMENTAL. The behaviour of this function, the name of this function, and anything else documented about this function may change without notice in a future release of PHP. Use this function at your own risk.

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

openssl_verify() verifies that the signature is correct for the specified data using the public key associated with pub_key_id. This must be the public key corresponding to the private key used for signing.

Example 1. openssl_verify() example

<?php
// $data and $signature are assumed to contain the data and the signature

// fetch public key from certificate and ready it
$fp = fopen("/src/openssl-0.9.6/demos/sign/cert.pem", "r");
$cert = fread($fp, 8192);
fclose($fp);
$pubkeyid = openssl_get_publickey($cert);

// state whether signature is okay or not
$ok = openssl_verify($data, $signature, $pubkeyid);
if (
$ok == 1) {
    echo
"good";
} elseif (
$ok == 0) {
    echo
"bad";
} else {
    echo
"ugly, error checking signature";
}
// free the key from memory
openssl_free_key($pubkeyid);
?>

See also openssl_sign().