The Tor Browser: ipc/chromium/src/base/hmac

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 // Copyright (c) 2008 The Chromium Authors. All rights reserved.

     2 // Use of this source code is governed by a BSD-style license that can be

     3 // found in the LICENSE file.

     5 #include "base/hmac.h"

     7 #include <CommonCrypto/CommonHMAC.h>

     9 #include "base/logging.h"

    11 namespace base {

    13 struct HMACPlatformData {

    14   std::string key_;

    15 };

    17 HMAC::HMAC(HashAlgorithm hash_alg)

    18     : hash_alg_(hash_alg), plat_(new HMACPlatformData()) {

    19   // Only SHA-1 digest is supported now.

    20   DCHECK(hash_alg_ == SHA1);

    21 }

    23 bool HMAC::Init(const unsigned char *key, int key_length) {

    24   if (!plat_->key_.empty()) {

    25     // Init must not be called more than once on the same HMAC object.

    26     NOTREACHED();

    27     return false;

    28   }

    30   plat_->key_.assign(reinterpret_cast<const char*>(key), key_length);

    32   return true;

    33 }

    35 HMAC::~HMAC() {

    36   // Zero out key copy.

    37   plat_->key_.assign(plat_->key_.length(), std::string::value_type());

    38   plat_->key_.clear();

    39   plat_->key_.reserve(0);

    40 }

    42 bool HMAC::Sign(const std::string& data,

    43                 unsigned char* digest,

    44                 int digest_length) {

    45   CCHmacAlgorithm algorithm;

    46   int algorithm_digest_length;

    47   switch (hash_alg_) {

    48     case SHA1:

    49       algorithm = kCCHmacAlgSHA1;

    50       algorithm_digest_length = CC_SHA1_DIGEST_LENGTH;

    51       break;

    52     default:

    53       NOTREACHED();

    54       return false;

    55   }

    57   if (digest_length < algorithm_digest_length) {

    58     NOTREACHED();

    59     return false;

    60   }

    62   CCHmac(algorithm,

    63          plat_->key_.data(), plat_->key_.length(), data.data(), data.length(),

    64          digest);

    66   return true;

    67 }

    69 }  // namespace base

The Tor Browser / file revision