In der wp-includes/pluggable.php finden wir die Funktion wp_hash_password, welche (ohne den Code für die Plugins) wie folgt aussieht

$s = new PasswordHash(8, true);
echo $s->HashPassword('test');

In selbiger Datei finden wir ebenfalls die Funktion wp_check_password, welche auf folgende Art und Weise Passwörter validiert:

$s = new PasswordHash(8, true);
$s->CheckPassword('test', '$P$123456789012345678901234567890');

Der String, der mit „$P$“ anfängt, ist hierbei ein über den am Anfang dieses Artikels genannten Code generierter Hash des Kennwortes.

Die Klasse „PasswordHash“ ist in der wp-includes/class-phpass.php defininiert und sieht wie folgt aus:

<?php
class PasswordHash {
	var $itoa64;
	var $iteration_count_log2;
	var $portable_hashes;
	var $random_state;
	function __construct( $iteration_count_log2, $portable_hashes )
	{
		$this->itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
		if ($iteration_count_log2 < 4 || $iteration_count_log2 > 31)
			$iteration_count_log2 = 8;
		$this->iteration_count_log2 = $iteration_count_log2;
		$this->portable_hashes = $portable_hashes;
		$this->random_state = microtime() . uniqid(rand(), TRUE);
	}
	public function PasswordHash( $iteration_count_log2, $portable_hashes ) {
		self::__construct( $iteration_count_log2, $portable_hashes );
	}
	function get_random_bytes($count)
	{
		$output = '';
		if ( @is_readable('/dev/urandom') &&
		    ($fh = @fopen('/dev/urandom', 'rb'))) {
			$output = fread($fh, $count);
			fclose($fh);
		}
		if (strlen($output) < $count) {
			$output = '';
			for ($i = 0; $i < $count; $i += 16) {
				$this->random_state =
				    md5(microtime() . $this->random_state);
				$output .=
				    pack('H*', md5($this->random_state));
			}
			$output = substr($output, 0, $count);
		}
		return $output;
	}
	function encode64($input, $count)
	{
		$output = '';
		$i = 0;
		do {
			$value = ord($input[$i++]);
			$output .= $this->itoa64[$value & 0x3f];
			if ($i < $count)
				$value |= ord($input[$i]) << 8;
			$output .= $this->itoa64[($value >> 6) & 0x3f];
			if ($i++ >= $count)
				break;
			if ($i < $count)
				$value |= ord($input[$i]) << 16;
			$output .= $this->itoa64[($value >> 12) & 0x3f];
			if ($i++ >= $count)
				break;
			$output .= $this->itoa64[($value >> 18) & 0x3f];
		} while ($i < $count);
		return $output;
	}
	function gensalt_private($input)
	{
		$output = '$P$';
		$output .= $this->itoa64[min($this->iteration_count_log2 +
			((PHP_VERSION >= '5') ? 5 : 3), 30)];
		$output .= $this->encode64($input, 6);
		return $output;
	}
	function crypt_private($password, $setting)
	{
		$output = '*0';
		if (substr($setting, 0, 2) == $output)
			$output = '*1';
		$id = substr($setting, 0, 3);
		if ($id != '$P$' && $id != '$H$')
			return $output;
		$count_log2 = strpos($this->itoa64, $setting[3]);
		if ($count_log2 < 7 || $count_log2 > 30)
			return $output;
		$count = 1 << $count_log2;
		$salt = substr($setting, 4, 8);
		if (strlen($salt) != 8)
			return $output;
		if (PHP_VERSION >= '5') {
			$hash = md5($salt . $password, TRUE);
			do {
				$hash = md5($hash . $password, TRUE);
			} while (--$count);
		} else {
			$hash = pack('H*', md5($salt . $password));
			do {
				$hash = pack('H*', md5($hash . $password));
			} while (--$count);
		}
		$output = substr($setting, 0, 12);
		$output .= $this->encode64($hash, 16);
		return $output;
	}
	function gensalt_extended($input)
	{
		$count_log2 = min($this->iteration_count_log2 + 8, 24);
		$count = (1 << $count_log2) - 1;
		$output = '_';
		$output .= $this->itoa64[$count & 0x3f];
		$output .= $this->itoa64[($count >> 6) & 0x3f];
		$output .= $this->itoa64[($count >> 12) & 0x3f];
		$output .= $this->itoa64[($count >> 18) & 0x3f];
		$output .= $this->encode64($input, 3);
		return $output;
	}
	function gensalt_blowfish($input)
	{
		$itoa64 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
		$output = '$2a$';
		$output .= chr(ord('0') + $this->iteration_count_log2 / 10);
		$output .= chr(ord('0') + $this->iteration_count_log2 % 10);
		$output .= '$';
		$i = 0;
		do {
			$c1 = ord($input[$i++]);
			$output .= $itoa64[$c1 >> 2];
			$c1 = ($c1 & 0x03) << 4;
			if ($i >= 16) {
				$output .= $itoa64[$c1];
				break;
			}
			$c2 = ord($input[$i++]);
			$c1 |= $c2 >> 4;
			$output .= $itoa64[$c1];
			$c1 = ($c2 & 0x0f) << 2;
			$c2 = ord($input[$i++]);
			$c1 |= $c2 >> 6;
			$output .= $itoa64[$c1];
			$output .= $itoa64[$c2 & 0x3f];
		} while (1);
		return $output;
	}
	function HashPassword($password)
	{
		if ( strlen( $password ) > 4096 ) {
			return '*';
		}
		$random = '';
		if (CRYPT_BLOWFISH == 1 && !$this->portable_hashes) {
			$random = $this->get_random_bytes(16);
			$hash =
			    crypt($password, $this->gensalt_blowfish($random));
			if (strlen($hash) == 60)
				return $hash;
		}
		if (CRYPT_EXT_DES == 1 && !$this->portable_hashes) {
			if (strlen($random) < 3)
				$random = $this->get_random_bytes(3);
			$hash =
			    crypt($password, $this->gensalt_extended($random));
			if (strlen($hash) == 20)
				return $hash;
		}
		if (strlen($random) < 6)
			$random = $this->get_random_bytes(6);
		$hash =
		    $this->crypt_private($password,
		    $this->gensalt_private($random));
		if (strlen($hash) == 34)
			return $hash;
		return '*';
	}
	function CheckPassword($password, $stored_hash)
	{
		if ( strlen( $password ) > 4096 ) {
			return false;
		}
		$hash = $this->crypt_private($password, $stored_hash);
		if ($hash[0] == '*')
			$hash = crypt($password, $stored_hash);
		return $hash === $stored_hash;
	}
}

Es reicht also aus, o.g. Klasse zu definieren und den Code ganz am Anfang dieses Beitrages auszuführen, um die Kennwörter so zu hashen, dass WordPress diese versteht.