wordpress密码生成与登录密码验证

一。研究wordpress时wordpess的密码密码生成与登录密码验证方式很重要

WordPress密码已成为整合的首要目标，如何征服整合，就得了解WordPress密码算法。

WordPress系统的用户密码是保存在wp_users数据表的user_pass字段，密码是通过Portable PHP password hashing framework类产生的，密码的形式是随机且不可逆，同一个明文的密码在不同时间，产生的密文也不一样，相对来说较为安全。

二。密码生成方式

> 随机产生一个salt 并将salt和password相加

> 进行了count次md5 然后和encode64的hash数值累加

> 最后得到一个以$P$开头的密码，这个密码每次产生的结果都不一样

以下为在wordpress中调用密码生成的代码

<?php
 $password = 'abc';
 global $wp_hasher;
 if ( empty($wp_hasher) ) {
  require_once( './wp-includes/class-phpass.php');
  $wp_hasher = new PasswordHash(8, TRUE);
 }
 echo $wp_hasher->HashPassword($password);
?>

三。wordpress密码生成与登录验证

wordpress中位置为\wp-includes\class-phpass.php

以下是wordpress中生成密码的代码直接运行可查看密码的生成以及验证过程

<?php

class PasswordHash {
	var $itoa64;
	var $iteration_count_log2;
	var $portable_hashes;
	var $random_state;

	function PasswordHash($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); // removed getmypid() for compability reasons
	}

	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)
	{
		$output = '$PXXXXX;
		$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);
		# We use "$P{1}quot;, phpBB3 uses "$H{1}quot; for the same thing
		if ($id != '$PXXXXX && $id != '$HXXXXX)
			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;

		# We're kind of forced to use MD5 here since it's the only
		# cryptographic primitive available in all versions of PHP
		# currently in use.  To implement our own low-level crypto
		# in PHP would result in much worse performance and
		# consequently in lower iteration counts and hashes that are
		# quicker to crack (by non-PHP code).
		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);
		# This should be odd to not reveal weak DES keys, and the
		# maximum valid value is (2**24 - 1) which is odd anyway.
		$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)
	{
		# This one needs to use a different order of characters and a
		# different encoding scheme from the one in encode64() above.
		# We care because the last character in our encoded string will
		# only represent 2 bits.  While two known implementations of
		# bcrypt will happily accept and correct a salt string which
		# has the 4 unused bits set to non-zero, we do not want to take
		# chances and we also do not want to waste an additional byte
		# of entropy.
		$itoa64 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';

		$output = '$2aXXXXX;
		$output .= chr(ord('0') + $this->iteration_count_log2 / 10);
		$output .= chr(ord('0') + $this->iteration_count_log2 % 10);
		$output .= 'XXXXX;

		$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)
	{
		$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;

		# Returning '*' on error is safe here, but would _not_ be safe
		# in a crypt(3)-like function used _both_ for generating new
		# hashes and for validating passwords against existing hashes.
		return '*';
	}

	function CheckPassword($password, $stored_hash)
	{
		$hash = $this->crypt_private($password, $stored_hash);
		if ($hash[0] == '*')
			$hash = crypt($password, $stored_hash);

		return $hash == $stored_hash;
	}
}

//原始密码
$passwordValue = "123456";

//生成密码
$wp_hasher = new PasswordHash(8, TRUE);
$sigPassword = $wp_hasher->HashPassword($passwordValue);
echo "生成的密码为:".$sigPassword;
echo "\n";

//验证密码
$data = $wp_hasher->CheckPassword($passwordValue,$sigPassword);
if($data){
    echo '密码正确';
}else{
	echo '密码错误';
}

?>

此为一个wordpres密码生成与登录验证实例，其中HashPassword为生成密码，CheckPassword为验证密码

itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz'; 为以上提到的生成salt的基础字符串。

备注：由于csdn代码显示插件对特殊字符的限制。 请将以上代码中 XXXXX替换为 $'  注意有单引号，代码中一共有5处

原博客链接：http://blog.csdn.net/chengfei112233/article/details/6939144/