<?php
/**
* Fingerprint Trait for Public Keys
*
* PHP version 5
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2015 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://phpseclib.sourceforge.net
*/
namespace phpseclib3\Crypt\Common\Traits;
use phpseclib3\Crypt\Hash;
/**
* Fingerprint Trait for Private Keys
*
* @author Jim Wigginton <terrafrost@php.net>
*/
trait Fingerprint
{
/**
* Returns the public key's fingerprint
*
* The public key's fingerprint is returned, which is equivalent to running `ssh-keygen -lf rsa.pub`. If there is
* no public key currently loaded, false is returned.
* Example output (md5): "c1:b1:30:29:d7:b8:de:6c:97:77:10:d7:46:41:63:87" (as specified by RFC 4716)
*
* @param string $algorithm The hashing algorithm to be used. Valid options are 'md5' and 'sha256'. False is returned
* for invalid values.
* @return mixed
*/
public function getFingerprint($algorithm = 'md5')
{
$type = self::validatePlugin('Keys', 'OpenSSH', 'savePublicKey');
if ($type === false) {
return false;
}
$key = $this->toString('OpenSSH', ['binary' => true]);
if ($key === false) {
return false;
}
switch ($algorithm) {
case 'sha256':
$hash = new Hash('sha256');
$base = base64_encode($hash->hash($key));
return substr($base, 0, strlen($base) - 1);
case 'md5':
return substr(chunk_split(md5($key), 2, ':'), 0, -1);
default:
return false;
}
}
}