PHP openssl_spki_export_challenge() Function
The openssl_spki_export_challenge() function is an inbuilt function in PHP and is used to export the signed public key and the challenge associated with it. It verifies a signed public key and challenge.
Syntax:
string openssl_spki_export_challenge( string &$spkac )
Parameters: This function accepts single parameter as mentioned above and described below:
- $spkac: This parameter is a format for sending a Certification Signing Request which encodes a public key that can be manipulated using openssl.
Return Values: This function returns the associated challenge string or NULL on failure.
Errors/Exceptions: If an invalid argument is passed using the “spkac” parameter, the E_WARNING level emits an error.
Below program illustrate the openssl_spki_export_challenge() function in PHP:
Program:
PHP
<?php $pkey = openssl_pkey_new(array("spki")); $inputChallengeString = "zambiatek"; // Generate a new key pair using // "zambiatek" as challenge string $spkac = openssl_spki_new( $pkey, $inputChallengeString); // Extract challenge key from key $extractedChallengeString = openssl_spki_export_challenge( preg_replace('/SPKAC=/', '', $spkac)); //if challenge string is not null if (! is_null($extractedChallengeString)) { echo "Used challenge string is:" . $inputChallengeString."\n"; // print challenge key echo "Extracted challenge string is:" . $extractedChallengeString . "\n"; } ?> |
Output:
Used challenge string is:zambiatek Extracted challenge string is:zambiatek
Reference: https://www.php.net/manual/en/function.openssl-spki-export-challenge.php
