openssl_spki_export

(PHP 5 >= 5.6.0, PHP 7)

Exports a valid PEM formatted public key signed public key and challenge

string openssl_spki_export ( string &$spkac )

Exports PEM formatted public key from encoded signed public key and challenge

Parameters:

spkac

Expects a valid signed public key and challenge

Returns:

Returns the associated PEM formatted public key or NULL on failure.

Exception:

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

Examples:

openssl_spki_export() example

Extracts the associated PEM formatted public key or NULL on failure.

<?php
$pkey = openssl_pkey_new('secret password');
$spkac = openssl_spki_new($pkey, 'challenge string');
$pubKey = openssl_spki_export(preg_replace('/SPKAC=/', '', $spkac));

if ($pubKey) {
    echo $pubKey;
}
?>

openssl_spki_export() example from <keygen>

Extracts the associated PEM formatted public key issued from the <keygen> element

<?php
$spkac = openssl_spki_export(preg_replace('/SPKAC=/', '', $_POST['spkac']));
if ($spkac != NULL) {
    echo $spkac;
} else {
    echo "Extraction of pub key failed";
}
?>
<keygen name="spkac" challenge="challenge string" keytype="RSA">