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LingotekOAuthSignatureMethod_HMAC_SHA1.php in Lingotek Translation 7.4

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lib/oauth-php/library/signature_method/LingotekOAuthSignatureMethod_HMAC_SHA1.php
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<?php

/**
 * OAuth signature implementation using HMAC-SHA1
 * 
 * @version $Id$
 * @author Marc Worrell <marcw@pobox.com>
 * @date  Sep 8, 2008 12:21:19 PM
 * 
 * The MIT License
 * 
 * Copyright (c) 2007-2008 Mediamatic Lab
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
require_once dirname(__FILE__) . '/LingotekOAuthSignatureMethod.class.php';
class LingotekOAuthSignatureMethod_HMAC_SHA1 extends LingotekOAuthSignatureMethod {
  public function name() {
    return 'HMAC-SHA1';
  }

  /**
   * Calculate the signature using HMAC-SHA1
   * This function is copyright Andy Smith, 2007.
   *
   * @param LingotekOAuthRequest request
   * @param string base_string
   * @param string consumer_secret
   * @param string token_secret
   * @return string
   */
  function signature($request, $base_string, $consumer_secret, $token_secret) {
    $key = $request
      ->urlencode($consumer_secret) . '&' . $request
      ->urlencode($token_secret);
    if (function_exists('hash_hmac')) {
      $signature = base64_encode(hash_hmac("sha1", $base_string, $key, true));
    }
    else {
      $blocksize = 64;
      $hashfunc = 'sha1';
      if (strlen($key) > $blocksize) {
        $key = pack('H*', $hashfunc($key));
      }
      $key = str_pad($key, $blocksize, chr(0x0));
      $ipad = str_repeat(chr(0x36), $blocksize);
      $opad = str_repeat(chr(0x5c), $blocksize);
      $hmac = pack('H*', $hashfunc(($key ^ $opad) . pack('H*', $hashfunc(($key ^ $ipad) . $base_string))));
      $signature = base64_encode($hmac);
    }
    return $request
      ->urlencode($signature);
  }

  /**
   * Check if the request signature corresponds to the one calculated for the request.
   *
   * @param LingotekOAuthRequest request
   * @param string base_string	data to be signed, usually the base string, can be a request body
   * @param string consumer_secret
   * @param string token_secret
   * @param string signature		from the request, still urlencoded
   * @return string
   */
  public function verify($request, $base_string, $consumer_secret, $token_secret, $signature) {
    $a = $request
      ->urldecode($signature);
    $b = $request
      ->urldecode($this
      ->signature($request, $base_string, $consumer_secret, $token_secret));

    // We have to compare the decoded values
    $valA = base64_decode($a);
    $valB = base64_decode($b);

    // Crude binary comparison
    return rawurlencode($valA) == rawurlencode($valB);
  }

}

/* vi:set ts=4 sts=4 sw=4 binary noeol: */