| Index: crypto/symmetric_key_mac.cc
|
| ===================================================================
|
| --- crypto/symmetric_key_mac.cc (revision 0)
|
| +++ crypto/symmetric_key_mac.cc (revision 0)
|
| @@ -0,0 +1,155 @@
|
| +// 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/symmetric_key.h"
|
| +
|
| +#include <CommonCrypto/CommonCryptor.h>
|
| +#include <CoreFoundation/CFString.h>
|
| +#include <Security/cssm.h>
|
| +
|
| +#include "base/logging.h"
|
| +#include "crypto/cssm_init.h"
|
| +
|
| +namespace {
|
| +
|
| +CSSM_KEY_TYPE CheckKeyParams(crypto::SymmetricKey::Algorithm algorithm,
|
| + size_t key_size_in_bits) {
|
| + if (algorithm == crypto::SymmetricKey::AES) {
|
| + CHECK(key_size_in_bits == 128 ||
|
| + key_size_in_bits == 192 ||
|
| + key_size_in_bits == 256)
|
| + << "Invalid key size " << key_size_in_bits << " bits";
|
| + return CSSM_ALGID_AES;
|
| + } else {
|
| + // FIPS 198 Section 3 requires a HMAC-SHA-1 derived keys to be at least
|
| + // (HMAC-SHA-1 output size / 2) to be compliant. Since the ouput size of
|
| + // HMAC-SHA-1 is 160 bits, we require at least 80 bits here.
|
| + CHECK(algorithm == crypto::SymmetricKey::HMAC_SHA1);
|
| + CHECK(key_size_in_bits >= 80 && (key_size_in_bits % 8) == 0)
|
| + << "Invalid key size " << key_size_in_bits << " bits";
|
| + return CSSM_ALGID_SHA1HMAC_LEGACY;
|
| + }
|
| +}
|
| +
|
| +void* CreateRandomBytes(size_t size) {
|
| + CSSM_RETURN err;
|
| + CSSM_CC_HANDLE ctx;
|
| + err = CSSM_CSP_CreateRandomGenContext(crypto::GetSharedCSPHandle(),
|
| + CSSM_ALGID_APPLE_YARROW,
|
| + NULL,
|
| + size, &ctx);
|
| + if (err) {
|
| + crypto::LogCSSMError("CSSM_CSP_CreateRandomGenContext", err);
|
| + return NULL;
|
| + }
|
| + CSSM_DATA random_data = {};
|
| + err = CSSM_GenerateRandom(ctx, &random_data);
|
| + if (err) {
|
| + crypto::LogCSSMError("CSSM_GenerateRandom", err);
|
| + random_data.Data = NULL;
|
| + }
|
| + CSSM_DeleteContext(ctx);
|
| + return random_data.Data; // Caller responsible for freeing this
|
| +}
|
| +
|
| +inline CSSM_DATA StringToData(const std::string& str) {
|
| + CSSM_DATA data = {
|
| + str.size(),
|
| + reinterpret_cast<uint8_t*>(const_cast<char*>(str.data()))
|
| + };
|
| + return data;
|
| +}
|
| +
|
| +} // namespace
|
| +
|
| +namespace crypto {
|
| +
|
| +SymmetricKey::~SymmetricKey() {}
|
| +
|
| +// static
|
| +SymmetricKey* SymmetricKey::GenerateRandomKey(Algorithm algorithm,
|
| + size_t key_size_in_bits) {
|
| + CheckKeyParams(algorithm, key_size_in_bits);
|
| + void* random_bytes = CreateRandomBytes((key_size_in_bits + 7) / 8);
|
| + if (!random_bytes)
|
| + return NULL;
|
| + SymmetricKey *key = new SymmetricKey(random_bytes, key_size_in_bits);
|
| + free(random_bytes);
|
| + return key;
|
| +}
|
| +
|
| +// static
|
| +SymmetricKey* SymmetricKey::DeriveKeyFromPassword(Algorithm algorithm,
|
| + const std::string& password,
|
| + const std::string& salt,
|
| + size_t iterations,
|
| + size_t key_size_in_bits) {
|
| + // Derived (haha) from cdsaDeriveKey() in Apple's CryptoSample.
|
| + CSSM_KEY_TYPE key_type = CheckKeyParams(algorithm, key_size_in_bits);
|
| + SymmetricKey* derived_key = NULL;
|
| + CSSM_KEY cssm_key = {};
|
| +
|
| + CSSM_CC_HANDLE ctx = 0;
|
| + CSSM_ACCESS_CREDENTIALS credentials = {};
|
| + CSSM_RETURN err;
|
| + CSSM_DATA salt_data = StringToData(salt);
|
| + err = CSSM_CSP_CreateDeriveKeyContext(GetSharedCSPHandle(),
|
| + CSSM_ALGID_PKCS5_PBKDF2,
|
| + key_type, key_size_in_bits,
|
| + &credentials,
|
| + NULL,
|
| + iterations,
|
| + &salt_data,
|
| + NULL,
|
| + &ctx);
|
| + if (err) {
|
| + LogCSSMError("CSSM_CSP_CreateDeriveKeyContext", err);
|
| + return NULL;
|
| + }
|
| +
|
| + CSSM_PKCS5_PBKDF2_PARAMS params = {};
|
| + params.Passphrase = StringToData(password);
|
| + params.PseudoRandomFunction = CSSM_PKCS5_PBKDF2_PRF_HMAC_SHA1;
|
| + CSSM_DATA param_data = {sizeof(params), reinterpret_cast<uint8_t*>(¶ms)};
|
| + err = CSSM_DeriveKey(ctx,
|
| + ¶m_data,
|
| + CSSM_KEYUSE_ANY,
|
| + CSSM_KEYATTR_RETURN_DATA | CSSM_KEYATTR_EXTRACTABLE,
|
| + NULL,
|
| + NULL,
|
| + &cssm_key);
|
| + if (err) {
|
| + LogCSSMError("CSSM_DeriveKey", err);
|
| + goto exit;
|
| + }
|
| +
|
| + DCHECK_EQ(cssm_key.KeyData.Length, key_size_in_bits / 8);
|
| + derived_key = new SymmetricKey(cssm_key.KeyData.Data, key_size_in_bits);
|
| +
|
| + exit:
|
| + CSSM_DeleteContext(ctx);
|
| + CSSM_FreeKey(GetSharedCSPHandle(), &credentials, &cssm_key, false);
|
| + return derived_key;
|
| +}
|
| +
|
| +// static
|
| +SymmetricKey* SymmetricKey::Import(Algorithm algorithm,
|
| + const std::string& raw_key) {
|
| + return new SymmetricKey(raw_key.data(), raw_key.size() * 8);
|
| +}
|
| +
|
| +SymmetricKey::SymmetricKey(const void *key_data, size_t key_size_in_bits)
|
| + : key_(reinterpret_cast<const char*>(key_data),
|
| + key_size_in_bits / 8) {}
|
| +
|
| +bool SymmetricKey::GetRawKey(std::string* raw_key) {
|
| + *raw_key = key_;
|
| + return true;
|
| +}
|
| +
|
| +CSSM_DATA SymmetricKey::cssm_data() const {
|
| + return StringToData(key_);
|
| +}
|
| +
|
| +} // namespace crypto
|
|
|
| Property changes on: crypto\symmetric_key_mac.cc
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
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|