1 <?php

     2 

     3 /*

     4  * Enano - an open-source CMS capable of wiki functions, Drupal-like sidebar blocks, and everything in between

     5  * Version 1.1.6 (Caoineag beta 1)

     6  * Copyright (C) 2006-2008 Dan Fuhry

     7  * hmac.php - HMAC cryptographic functions

     8  *

     9  * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License

    10  * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

    11  *

    12  * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied

    13  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for details.

    14  */

    15 

    16 function hmac_gen_padding($val, $len = 32)

    17 {

    18   $ret = array();

    19   for ( $i = 0; $i < $len; $i++ )

    20   {

    21     $ret[] = $val;

    22   }

    23   return $ret;

    24 }

    25 

    26 function hmac_core($message, $key, $hashfunc)

    27 {

    28   static $block_sizes = array();

    29   if ( !isset($block_sizes[$hashfunc]) )

    30   {

    31     $block_sizes[$hashfunc] = strlen($hashfunc(''))/2;

    32   }

    33   $blocksize = $block_sizes[$hashfunc];

    34   $ipad = hmac_gen_padding(0x5c, $blocksize);

    35   $opad = hmac_gen_padding(0x36, $blocksize);

    36   if ( strlen($key) != ( $blocksize * 2 ) )

    37     $key = $hashfunc($key);

    38   $key = hmac_hexbytearray($key);

    39   for ( $i = 0; $i < count($key); $i++ )

    40   {

    41     $ipad[$i] = $ipad[$i] ^ $key[$i];

    42     $opad[$i] = $opad[$i] ^ $key[$i];

    43   }

    44   return $hashfunc(hmac_bytearraytostring($opad) . $hashfunc(hmac_bytearraytostring($ipad) . $message));

    45 }

    46 

    47 function hmac_hexbytearray($val)

    48 {

    49   $val = hexdecode($val);

    50   return hmac_bytearray($val);

    51 }

    52 

    53 function hmac_bytearray($val)

    54 {

    55   $val = str_split($val, 1);

    56   foreach ( $val as &$char )

    57   {

    58     $char = ord($char);

    59   }

    60   return $val;

    61 }

    62 

    63 function hmac_bytearraytostring($val)

    64 {

    65   foreach ( $val as &$char )

    66   {

    67     $char = chr($char);

    68   }

    69   return implode('', $val);

    70 }

    71 

    72 function hmac_md5($message, $key)

    73 {

    74   return hmac_core($message, $key, 'md5');

    75 }

    76 

    77 function hmac_sha1($message, $key)

    78 {

    79   return hmac_core($message, $key, 'sha1');

    80 }

    81 

    82 function hmac_sha256($message, $key)

    83 {

    84   require_once(ENANO_ROOT . '/includes/math.php');

    85   require_once(ENANO_ROOT . '/includes/diffiehellman.php');

    86   return hmac_core($message, $key, 'sha256');

    87 }

    88 

    89 ?>