Reland "Cut down /crypto and switch what is left of it to boringssl".

crypto/hmac_openssl.cc

-// Copyright (c) 2011 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 "crypto/hmac.h"
-
-#include <openssl/hmac.h>
-
-#include <algorithm>
-#include <vector>
-
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/stl_util.h"
-#include "crypto/openssl_util.h"
-
-namespace crypto {
-
-struct HMACPlatformData {
-  std::vector<unsigned char> 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, size_t key_length) {
-  // Init must not be called more than once on the same HMAC object.
-  DCHECK(plat_->key.empty());
-
-  plat_->key.assign(key, key + key_length);
-  if (key_length == 0) {
-    // Special-case: if the key is empty, use a key with one zero
-    // byte. OpenSSL's HMAC function breaks when passed a NULL key. (It calls
-    // HMAC_Init_ex which treats a NULL key as having already been initialized
-    // with a key previously.) HMAC pads keys with zeros, so this key is
-    // equivalent.
-    plat_->key.push_back(0);
-  }
-  return true;
-}
-
-HMAC::~HMAC() {
-  // Zero out key copy.
-  plat_->key.assign(plat_->key.size(), 0);
-  STLClearObject(&plat_->key);
-}
-
-bool HMAC::Sign(const base::StringPiece& data,
-                unsigned char* digest,
-                size_t digest_length) const {
-  DCHECK(!plat_->key.empty());  // Init must be called before Sign.
-
-  ScopedOpenSSLSafeSizeBuffer<EVP_MAX_MD_SIZE> result(digest, digest_length);
-  return !!::HMAC(hash_alg_ == SHA1 ? EVP_sha1() : EVP_sha256(),
-                &plat_->key[0], plat_->key.size(),
-                reinterpret_cast<const unsigned char*>(data.data()),
-                data.size(),
-                result.safe_buffer(), NULL);
-}
-
-}  // namespace crypto