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   1  <?php
   2  #
   3  # Portable PHP password hashing framework.
   4  #
   5  # Version 0.5 / genuine.
   6  #
   7  # Written by Solar Designer <solar at openwall.com> in 2004-2006 and placed in
   8  # the public domain.  Revised in subsequent years, still public domain.
   9  #
  10  # There's absolutely no warranty.
  11  #
  12  # The homepage URL for this framework is:
  13  #
  14  #    http://www.openwall.com/phpass/
  15  #
  16  # Please be sure to update the Version line if you edit this file in any way.
  17  # It is suggested that you leave the main version number intact, but indicate
  18  # your project name (after the slash) and add your own revision information.
  19  #
  20  # Please do not change the "private" password hashing method implemented in
  21  # here, thereby making your hashes incompatible.  However, if you must, please
  22  # change the hash type identifier (the "$P$") to something different.
  23  #
  24  # Obviously, since this code is in the public domain, the above are not
  25  # requirements (there can be none), but merely suggestions.
  26  #
  27  class PasswordHash {
  28      var $itoa64;
  29      var $iteration_count_log2;
  30      var $portable_hashes;
  31      var $random_state;
  32  
  33  	function __construct($iteration_count_log2, $portable_hashes)
  34      {
  35          $this->itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
  36  
  37          if ($iteration_count_log2 < 4 || $iteration_count_log2 > 31)
  38              $iteration_count_log2 = 8;
  39          $this->iteration_count_log2 = $iteration_count_log2;
  40  
  41          $this->portable_hashes = $portable_hashes;
  42  
  43          $this->random_state = microtime();
  44          if (function_exists('getmypid'))
  45              $this->random_state .= getmypid();
  46      }
  47  
  48  	function PasswordHash($iteration_count_log2, $portable_hashes)
  49      {
  50          self::__construct($iteration_count_log2, $portable_hashes);
  51      }
  52  
  53  	function get_random_bytes($count)
  54      {
  55          $output = '';
  56          if (@is_readable('/dev/urandom') &&
  57              ($fh = @fopen('/dev/urandom', 'rb'))) {
  58              $output = fread($fh, $count);
  59              fclose($fh);
  60          }
  61  
  62          if (strlen($output) < $count) {
  63              $output = '';
  64              for ($i = 0; $i < $count; $i += 16) {
  65                  $this->random_state =
  66                      md5(microtime() . $this->random_state);
  67                  $output .= md5($this->random_state, TRUE);
  68              }
  69              $output = substr($output, 0, $count);
  70          }
  71  
  72          return $output;
  73      }
  74  
  75  	function encode64($input, $count)
  76      {
  77          $output = '';
  78          $i = 0;
  79          do {
  80              $value = ord($input[$i++]);
  81              $output .= $this->itoa64[$value & 0x3f];
  82              if ($i < $count)
  83                  $value |= ord($input[$i]) << 8;
  84              $output .= $this->itoa64[($value >> 6) & 0x3f];
  85              if ($i++ >= $count)
  86                  break;
  87              if ($i < $count)
  88                  $value |= ord($input[$i]) << 16;
  89              $output .= $this->itoa64[($value >> 12) & 0x3f];
  90              if ($i++ >= $count)
  91                  break;
  92              $output .= $this->itoa64[($value >> 18) & 0x3f];
  93          } while ($i < $count);
  94  
  95          return $output;
  96      }
  97  
  98  	function gensalt_private($input)
  99      {
 100          $output = '$P$';
 101          $output .= $this->itoa64[min($this->iteration_count_log2 +
 102              ((PHP_VERSION >= '5') ? 5 : 3), 30)];
 103          $output .= $this->encode64($input, 6);
 104  
 105          return $output;
 106      }
 107  
 108  	function crypt_private($password, $setting)
 109      {
 110          $output = '*0';
 111          if (substr($setting, 0, 2) === $output)
 112              $output = '*1';
 113  
 114          $id = substr($setting, 0, 3);
 115          # We use "$P$", phpBB3 uses "$H$" for the same thing
 116          if ($id !== '$P$' && $id !== '$H$')
 117              return $output;
 118  
 119          $count_log2 = strpos($this->itoa64, $setting[3]);
 120          if ($count_log2 < 7 || $count_log2 > 30)
 121              return $output;
 122  
 123          $count = 1 << $count_log2;
 124  
 125          $salt = substr($setting, 4, 8);
 126          if (strlen($salt) !== 8)
 127              return $output;
 128  
 129          # We were kind of forced to use MD5 here since it's the only
 130          # cryptographic primitive that was available in all versions
 131          # of PHP in use.  To implement our own low-level crypto in PHP
 132          # would have resulted in much worse performance and
 133          # consequently in lower iteration counts and hashes that are
 134          # quicker to crack (by non-PHP code).
 135          $hash = md5($salt . $password, TRUE);
 136          do {
 137              $hash = md5($hash . $password, TRUE);
 138          } while (--$count);
 139  
 140          $output = substr($setting, 0, 12);
 141          $output .= $this->encode64($hash, 16);
 142  
 143          return $output;
 144      }
 145  
 146  	function gensalt_blowfish($input)
 147      {
 148          # This one needs to use a different order of characters and a
 149          # different encoding scheme from the one in encode64() above.
 150          # We care because the last character in our encoded string will
 151          # only represent 2 bits.  While two known implementations of
 152          # bcrypt will happily accept and correct a salt string which
 153          # has the 4 unused bits set to non-zero, we do not want to take
 154          # chances and we also do not want to waste an additional byte
 155          # of entropy.
 156          $itoa64 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
 157  
 158          $output = '$2a$';
 159          $output .= chr(ord('0') + $this->iteration_count_log2 / 10);
 160          $output .= chr(ord('0') + $this->iteration_count_log2 % 10);
 161          $output .= '$';
 162  
 163          $i = 0;
 164          do {
 165              $c1 = ord($input[$i++]);
 166              $output .= $itoa64[$c1 >> 2];
 167              $c1 = ($c1 & 0x03) << 4;
 168              if ($i >= 16) {
 169                  $output .= $itoa64[$c1];
 170                  break;
 171              }
 172  
 173              $c2 = ord($input[$i++]);
 174              $c1 |= $c2 >> 4;
 175              $output .= $itoa64[$c1];
 176              $c1 = ($c2 & 0x0f) << 2;
 177  
 178              $c2 = ord($input[$i++]);
 179              $c1 |= $c2 >> 6;
 180              $output .= $itoa64[$c1];
 181              $output .= $itoa64[$c2 & 0x3f];
 182          } while (1);
 183  
 184          return $output;
 185      }
 186  
 187  	function HashPassword($password)
 188      {
 189          $random = '';
 190  
 191          if (CRYPT_BLOWFISH === 1 && !$this->portable_hashes) {
 192              $random = $this->get_random_bytes(16);
 193              $hash =
 194                  crypt($password, $this->gensalt_blowfish($random));
 195              if (strlen($hash) === 60)
 196                  return $hash;
 197          }
 198  
 199          if (strlen($random) < 6)
 200              $random = $this->get_random_bytes(6);
 201          $hash =
 202              $this->crypt_private($password,
 203              $this->gensalt_private($random));
 204          if (strlen($hash) === 34)
 205              return $hash;
 206  
 207          # Returning '*' on error is safe here, but would _not_ be safe
 208          # in a crypt(3)-like function used _both_ for generating new
 209          # hashes and for validating passwords against existing hashes.
 210          return '*';
 211      }
 212  
 213  	function CheckPassword($password, $stored_hash)
 214      {
 215          $hash = $this->crypt_private($password, $stored_hash);
 216          if ($hash[0] === '*')
 217              $hash = crypt($password, $stored_hash);
 218  
 219          # This is not constant-time.  In order to keep the code simple,
 220          # for timing safety we currently rely on the salts being
 221          # unpredictable, which they are at least in the non-fallback
 222          # cases (that is, when we use /dev/urandom and bcrypt).
 223          return $hash === $stored_hash;
 224      }
 225  }
 226  
 227  ?>