openssl_spki_verify

(PHP 5 >= 5.6.0, PHP 7)

Verifies a signed public key and challenge

string openssl_spki_verify ( string &$spkac )

Validates the supplied signed public key and challenge

Parameters:

spkac

Expects a valid signed public key and challenge

Returns:

Returns a boolean on success or failure.

Exception:

Emits an E_WARNING level error if an invalid argument is passed via the spkac parameter.

Examples:

openssl_spki_verify() example

Validates an existing signed public key and challenge

<?php
$pkey = openssl_pkey_new('secret password');
$spkac = openssl_spki_new($pkey, 'challenge string');

if (openssl_spki_verify(preg_replace('/SPKAC=/', '', $spkac))) {
    echo $spkac;
} else {
    echo "SPKAC validation failed";
}
?>

openssl_spki_verify() example from <keygen>

Validates an existing signed public key and challenge issued from the <keygen> element

<?php
if (openssl_spki_verify(preg_replace('/SPKAC=/', '', $_POST['spkac']))) {
    echo $spkac;
} else {
    echo "SPKAC validation failed";
}
?>
<keygen name="spkac" challenge="challenge string" keytype="RSA">