| Index: base/hmac_win.cc
|
| ===================================================================
|
| --- base/hmac_win.cc (revision 80572)
|
| +++ base/hmac_win.cc (working copy)
|
| @@ -1,197 +0,0 @@
|
| -// Copyright (c) 2010 The Chromium Authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -#include "base/hmac.h"
|
| -
|
| -#include <windows.h>
|
| -#include <wincrypt.h>
|
| -
|
| -#include <algorithm>
|
| -#include <vector>
|
| -
|
| -#include "base/crypto/scoped_capi_types.h"
|
| -#include "base/logging.h"
|
| -#include "base/third_party/nss/blapi.h"
|
| -#include "base/third_party/nss/sha256.h"
|
| -
|
| -namespace base {
|
| -
|
| -namespace {
|
| -
|
| -// Implementation of HMAC-SHA-256:
|
| -//
|
| -// SHA-256 is supported in Windows XP SP3 or later. We still need to support
|
| -// Windows XP SP2, so unfortunately we have to implement HMAC-SHA-256 here.
|
| -
|
| -enum {
|
| - SHA256_BLOCK_SIZE = 64 // Block size (in bytes) of the input to SHA-256.
|
| -};
|
| -
|
| -// See FIPS 198: The Keyed-Hash Message Authentication Code (HMAC).
|
| -void ComputeHMACSHA256(const unsigned char* key, size_t key_len,
|
| - const unsigned char* text, size_t text_len,
|
| - unsigned char* output, size_t output_len) {
|
| - SHA256Context ctx;
|
| -
|
| - // Pre-process the key, if necessary.
|
| - unsigned char key0[SHA256_BLOCK_SIZE];
|
| - if (key_len > SHA256_BLOCK_SIZE) {
|
| - SHA256_Begin(&ctx);
|
| - SHA256_Update(&ctx, key, key_len);
|
| - SHA256_End(&ctx, key0, NULL, SHA256_LENGTH);
|
| - memset(key0 + SHA256_LENGTH, 0, SHA256_BLOCK_SIZE - SHA256_LENGTH);
|
| - } else {
|
| - memcpy(key0, key, key_len);
|
| - memset(key0 + key_len, 0, SHA256_BLOCK_SIZE - key_len);
|
| - }
|
| -
|
| - unsigned char padded_key[SHA256_BLOCK_SIZE];
|
| - unsigned char inner_hash[SHA256_LENGTH];
|
| -
|
| - // XOR key0 with ipad.
|
| - for (int i = 0; i < SHA256_BLOCK_SIZE; ++i)
|
| - padded_key[i] = key0[i] ^ 0x36;
|
| -
|
| - // Compute the inner hash.
|
| - SHA256_Begin(&ctx);
|
| - SHA256_Update(&ctx, padded_key, SHA256_BLOCK_SIZE);
|
| - SHA256_Update(&ctx, text, text_len);
|
| - SHA256_End(&ctx, inner_hash, NULL, SHA256_LENGTH);
|
| -
|
| - // XOR key0 with opad.
|
| - for (int i = 0; i < SHA256_BLOCK_SIZE; ++i)
|
| - padded_key[i] = key0[i] ^ 0x5c;
|
| -
|
| - // Compute the outer hash.
|
| - SHA256_Begin(&ctx);
|
| - SHA256_Update(&ctx, padded_key, SHA256_BLOCK_SIZE);
|
| - SHA256_Update(&ctx, inner_hash, SHA256_LENGTH);
|
| - SHA256_End(&ctx, output, NULL, output_len);
|
| -}
|
| -
|
| -} // namespace
|
| -
|
| -struct HMACPlatformData {
|
| - ~HMACPlatformData() {
|
| - if (!raw_key_.empty()) {
|
| - SecureZeroMemory(&raw_key_[0], raw_key_.size());
|
| - }
|
| -
|
| - // Destroy the key before releasing the provider.
|
| - key_.reset();
|
| - }
|
| -
|
| - ScopedHCRYPTPROV provider_;
|
| - ScopedHCRYPTKEY key_;
|
| -
|
| - // For HMAC-SHA-256 only.
|
| - std::vector<unsigned char> raw_key_;
|
| -};
|
| -
|
| -HMAC::HMAC(HashAlgorithm hash_alg)
|
| - : hash_alg_(hash_alg), plat_(new HMACPlatformData()) {
|
| - // Only SHA-1 and SHA-256 hash algorithms are supported now.
|
| - DCHECK(hash_alg_ == SHA1 || hash_alg_ == SHA256);
|
| -}
|
| -
|
| -bool HMAC::Init(const unsigned char* key, int key_length) {
|
| - if (plat_->provider_ || plat_->key_ || !plat_->raw_key_.empty()) {
|
| - // Init must not be called more than once on the same HMAC object.
|
| - NOTREACHED();
|
| - return false;
|
| - }
|
| -
|
| - if (hash_alg_ == SHA256) {
|
| - if (key_length < SHA256_LENGTH / 2)
|
| - return false; // Key is too short.
|
| - plat_->raw_key_.assign(key, key + key_length);
|
| - return true;
|
| - }
|
| -
|
| - if (!CryptAcquireContext(plat_->provider_.receive(), NULL, NULL,
|
| - PROV_RSA_FULL, CRYPT_VERIFYCONTEXT)) {
|
| - NOTREACHED();
|
| - return false;
|
| - }
|
| -
|
| - // This code doesn't work on Win2k because PLAINTEXTKEYBLOB and
|
| - // CRYPT_IPSEC_HMAC_KEY are not supported on Windows 2000. PLAINTEXTKEYBLOB
|
| - // allows the import of an unencrypted key. For Win2k support, a cubmbersome
|
| - // exponent-of-one key procedure must be used:
|
| - // http://support.microsoft.com/kb/228786/en-us
|
| - // CRYPT_IPSEC_HMAC_KEY allows keys longer than 16 bytes.
|
| -
|
| - struct KeyBlob {
|
| - BLOBHEADER header;
|
| - DWORD key_size;
|
| - BYTE key_data[1];
|
| - };
|
| - size_t key_blob_size = std::max(offsetof(KeyBlob, key_data) + key_length,
|
| - sizeof(KeyBlob));
|
| - std::vector<BYTE> key_blob_storage = std::vector<BYTE>(key_blob_size);
|
| - KeyBlob* key_blob = reinterpret_cast<KeyBlob*>(&key_blob_storage[0]);
|
| - key_blob->header.bType = PLAINTEXTKEYBLOB;
|
| - key_blob->header.bVersion = CUR_BLOB_VERSION;
|
| - key_blob->header.reserved = 0;
|
| - key_blob->header.aiKeyAlg = CALG_RC2;
|
| - key_blob->key_size = key_length;
|
| - memcpy(key_blob->key_data, key, key_length);
|
| -
|
| - if (!CryptImportKey(plat_->provider_, &key_blob_storage[0],
|
| - key_blob_storage.size(), 0, CRYPT_IPSEC_HMAC_KEY,
|
| - plat_->key_.receive())) {
|
| - NOTREACHED();
|
| - return false;
|
| - }
|
| -
|
| - // Destroy the copy of the key.
|
| - SecureZeroMemory(key_blob->key_data, key_length);
|
| -
|
| - return true;
|
| -}
|
| -
|
| -HMAC::~HMAC() {
|
| -}
|
| -
|
| -bool HMAC::Sign(const std::string& data,
|
| - unsigned char* digest,
|
| - int digest_length) {
|
| - if (hash_alg_ == SHA256) {
|
| - if (plat_->raw_key_.empty())
|
| - return false;
|
| - ComputeHMACSHA256(&plat_->raw_key_[0], plat_->raw_key_.size(),
|
| - reinterpret_cast<const unsigned char*>(data.data()),
|
| - data.size(), digest, digest_length);
|
| - return true;
|
| - }
|
| -
|
| - if (!plat_->provider_ || !plat_->key_)
|
| - return false;
|
| -
|
| - if (hash_alg_ != SHA1) {
|
| - NOTREACHED();
|
| - return false;
|
| - }
|
| -
|
| - ScopedHCRYPTHASH hash;
|
| - if (!CryptCreateHash(plat_->provider_, CALG_HMAC, plat_->key_, 0,
|
| - hash.receive()))
|
| - return false;
|
| -
|
| - HMAC_INFO hmac_info;
|
| - memset(&hmac_info, 0, sizeof(hmac_info));
|
| - hmac_info.HashAlgid = CALG_SHA1;
|
| - if (!CryptSetHashParam(hash, HP_HMAC_INFO,
|
| - reinterpret_cast<BYTE*>(&hmac_info), 0))
|
| - return false;
|
| -
|
| - if (!CryptHashData(hash, reinterpret_cast<const BYTE*>(data.data()),
|
| - static_cast<DWORD>(data.size()), 0))
|
| - return false;
|
| -
|
| - DWORD sha1_size = digest_length;
|
| - return !!CryptGetHashParam(hash, HP_HASHVAL, digest, &sha1_size, 0);
|
| -}
|
| -
|
| -} // namespace base
|
|
|