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