license.bot | f003cfe | 2008-08-24 09:55:55 +0900 | [diff] [blame^] | 1 | // Copyright (c) 2006-2008 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. |
initial.commit | 3f4a732 | 2008-07-27 06:49:38 +0900 | [diff] [blame] | 4 | |
| 5 | #include "base/hmac.h" |
| 6 | #include "base/logging.h" |
| 7 | |
| 8 | HMAC::HMAC(HashAlgorithm hash_alg, const unsigned char* key, int key_length) |
| 9 | : hash_alg_(hash_alg), |
| 10 | provider_(NULL), |
| 11 | hash_(NULL), |
| 12 | hkey_(NULL) { |
| 13 | if (!CryptAcquireContext(&provider_, NULL, NULL, |
| 14 | PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)) |
| 15 | provider_ = NULL; |
| 16 | ImportKey(key, key_length); |
| 17 | } |
| 18 | |
| 19 | HMAC::~HMAC() { |
| 20 | if (hkey_) |
| 21 | CryptDestroyKey(hkey_); |
| 22 | if (hash_) |
| 23 | CryptDestroyHash(hash_); |
| 24 | if (provider_) |
| 25 | CryptReleaseContext(provider_, 0); |
| 26 | } |
| 27 | |
| 28 | bool HMAC::Sign(const std::string& data, |
| 29 | unsigned char* digest, |
| 30 | int digest_length) { |
| 31 | if (!provider_ || !hkey_) |
| 32 | return false; |
| 33 | |
| 34 | switch (hash_alg_) { |
| 35 | case SHA1: |
| 36 | return SignWithSHA1(data, digest, digest_length); |
| 37 | default: |
| 38 | NOTREACHED(); |
| 39 | return false; |
| 40 | } |
| 41 | } |
| 42 | |
| 43 | void HMAC::ImportKey(const unsigned char* key, int key_length) { |
| 44 | if (key_length > kMaxKeySize) { |
| 45 | NOTREACHED(); |
| 46 | return; |
| 47 | } |
| 48 | |
| 49 | struct { |
| 50 | BLOBHEADER header; |
| 51 | DWORD key_size; |
| 52 | BYTE key_data[kMaxKeySize]; |
| 53 | } key_blob; |
| 54 | key_blob.header.bType = PLAINTEXTKEYBLOB; |
| 55 | key_blob.header.bVersion = CUR_BLOB_VERSION; |
| 56 | key_blob.header.reserved = 0; |
| 57 | key_blob.header.aiKeyAlg = CALG_RC2; |
| 58 | key_blob.key_size = key_length; |
| 59 | memcpy(key_blob.key_data, key, key_length); |
| 60 | |
| 61 | if (!CryptImportKey(provider_, |
| 62 | reinterpret_cast<const BYTE *>(&key_blob), |
| 63 | sizeof(key_blob), 0, 0, &hkey_)) |
| 64 | hkey_ = NULL; |
| 65 | |
| 66 | // Destroy the copy of the key. |
| 67 | SecureZeroMemory(key_blob.key_data, key_length); |
| 68 | } |
| 69 | |
| 70 | bool HMAC::SignWithSHA1(const std::string& data, |
| 71 | unsigned char* digest, |
| 72 | int digest_length) { |
| 73 | DCHECK(provider_); |
| 74 | DCHECK(hkey_); |
| 75 | |
| 76 | if (!CryptCreateHash(provider_, CALG_HMAC, hkey_, 0, &hash_)) |
| 77 | return false; |
| 78 | |
| 79 | HMAC_INFO hmac_info; |
| 80 | memset(&hmac_info, 0, sizeof(hmac_info)); |
| 81 | hmac_info.HashAlgid = CALG_SHA1; |
| 82 | if (!CryptSetHashParam(hash_, HP_HMAC_INFO, |
| 83 | reinterpret_cast<BYTE*>(&hmac_info), 0)) |
| 84 | return false; |
| 85 | |
| 86 | if (!CryptHashData(hash_, |
| 87 | reinterpret_cast<const BYTE*>(data.data()), |
| 88 | static_cast<DWORD>(data.size()), 0)) |
| 89 | return false; |
| 90 | |
| 91 | DWORD sha1_size = digest_length; |
| 92 | if (!CryptGetHashParam(hash_, HP_HASHVAL, digest, &sha1_size, 0)) |
| 93 | return false; |
| 94 | |
| 95 | return true; |
| 96 | } |
license.bot | f003cfe | 2008-08-24 09:55:55 +0900 | [diff] [blame^] | 97 | |