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// Copyright 2014 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 <stddef.h>
#include <stdint.h>
#include "base/macros.h"
#include "base/values.h"
#include "components/webcrypto/algorithm_dispatch.h"
#include "components/webcrypto/algorithms/test_helpers.h"
#include "components/webcrypto/crypto_data.h"
#include "components/webcrypto/status.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
#include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
namespace webcrypto {
namespace {
// Creates an AES-GCM algorithm.
blink::WebCryptoAlgorithm CreateAesGcmAlgorithm(
const std::vector<uint8_t>& iv,
const std::vector<uint8_t>& additional_data,
unsigned int tag_length_bits) {
return blink::WebCryptoAlgorithm::adoptParamsAndCreate(
blink::WebCryptoAlgorithmIdAesGcm,
new blink::WebCryptoAesGcmParams(iv, true, additional_data, true,
tag_length_bits));
}
blink::WebCryptoAlgorithm CreateAesGcmKeyGenAlgorithm(
unsigned short key_length_bits) {
return CreateAesKeyGenAlgorithm(blink::WebCryptoAlgorithmIdAesGcm,
key_length_bits);
}
Status AesGcmEncrypt(const blink::WebCryptoKey& key,
const std::vector<uint8_t>& iv,
const std::vector<uint8_t>& additional_data,
unsigned int tag_length_bits,
const std::vector<uint8_t>& plain_text,
std::vector<uint8_t>* cipher_text,
std::vector<uint8_t>* authentication_tag) {
blink::WebCryptoAlgorithm algorithm =
CreateAesGcmAlgorithm(iv, additional_data, tag_length_bits);
std::vector<uint8_t> output;
Status status = Encrypt(algorithm, key, CryptoData(plain_text), &output);
if (status.IsError())
return status;
if ((tag_length_bits % 8) != 0) {
ADD_FAILURE() << "Encrypt should have failed.";
return Status::OperationError();
}
size_t tag_length_bytes = tag_length_bits / 8;
if (tag_length_bytes > output.size()) {
ADD_FAILURE() << "tag length is larger than output";
return Status::OperationError();
}
// The encryption result is cipher text with authentication tag appended.
cipher_text->assign(output.begin(),
output.begin() + (output.size() - tag_length_bytes));
authentication_tag->assign(output.begin() + cipher_text->size(),
output.end());
return Status::Success();
}
Status AesGcmDecrypt(const blink::WebCryptoKey& key,
const std::vector<uint8_t>& iv,
const std::vector<uint8_t>& additional_data,
unsigned int tag_length_bits,
const std::vector<uint8_t>& cipher_text,
const std::vector<uint8_t>& authentication_tag,
std::vector<uint8_t>* plain_text) {
blink::WebCryptoAlgorithm algorithm =
CreateAesGcmAlgorithm(iv, additional_data, tag_length_bits);
// Join cipher text and authentication tag.
std::vector<uint8_t> cipher_text_with_tag;
cipher_text_with_tag.reserve(cipher_text.size() + authentication_tag.size());
cipher_text_with_tag.insert(cipher_text_with_tag.end(), cipher_text.begin(),
cipher_text.end());
cipher_text_with_tag.insert(cipher_text_with_tag.end(),
authentication_tag.begin(),
authentication_tag.end());
return Decrypt(algorithm, key, CryptoData(cipher_text_with_tag), plain_text);
}
class WebCryptoAesGcmTest : public WebCryptoTestBase {};
TEST_F(WebCryptoAesGcmTest, GenerateKeyBadLength) {
const unsigned short kKeyLen[] = {0, 127, 257};
blink::WebCryptoKey key;
for (size_t i = 0; i < arraysize(kKeyLen); ++i) {
SCOPED_TRACE(i);
EXPECT_EQ(Status::ErrorGenerateAesKeyLength(),
GenerateSecretKey(CreateAesGcmKeyGenAlgorithm(kKeyLen[i]), true,
blink::WebCryptoKeyUsageDecrypt, &key));
}
}
TEST_F(WebCryptoAesGcmTest, GenerateKeyEmptyUsage) {
blink::WebCryptoKey key;
EXPECT_EQ(Status::ErrorCreateKeyEmptyUsages(),
GenerateSecretKey(CreateAesGcmKeyGenAlgorithm(256), true, 0, &key));
}
TEST_F(WebCryptoAesGcmTest, ImportExportJwk) {
const blink::WebCryptoAlgorithm algorithm =
CreateAlgorithm(blink::WebCryptoAlgorithmIdAesGcm);
// AES-GCM 128
ImportExportJwkSymmetricKey(
128, algorithm,
blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageDecrypt,
"A128GCM");
// AES-GCM 256
ImportExportJwkSymmetricKey(256, algorithm, blink::WebCryptoKeyUsageDecrypt,
"A256GCM");
}
// TODO(eroman):
// * Test decryption when the tag length exceeds input size
// * Test decryption with empty input
// * Test decryption with tag length of 0.
TEST_F(WebCryptoAesGcmTest, SampleSets) {
std::unique_ptr<base::ListValue> tests;
ASSERT_TRUE(ReadJsonTestFileToList("aes_gcm.json", &tests));
// Note that WebCrypto appends the authentication tag to the ciphertext.
for (size_t test_index = 0; test_index < tests->GetSize(); ++test_index) {
SCOPED_TRACE(test_index);
base::DictionaryValue* test;
ASSERT_TRUE(tests->GetDictionary(test_index, &test));
const std::vector<uint8_t> test_key = GetBytesFromHexString(test, "key");
const std::vector<uint8_t> test_iv = GetBytesFromHexString(test, "iv");
const std::vector<uint8_t> test_additional_data =
GetBytesFromHexString(test, "additional_data");
const std::vector<uint8_t> test_plain_text =
GetBytesFromHexString(test, "plain_text");
const std::vector<uint8_t> test_authentication_tag =
GetBytesFromHexString(test, "authentication_tag");
const unsigned int test_tag_size_bits =
static_cast<unsigned int>(test_authentication_tag.size()) * 8;
const std::vector<uint8_t> test_cipher_text =
GetBytesFromHexString(test, "cipher_text");
blink::WebCryptoKey key = ImportSecretKeyFromRaw(
test_key, CreateAlgorithm(blink::WebCryptoAlgorithmIdAesGcm),
blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageDecrypt);
// Verify exported raw key is identical to the imported data
std::vector<uint8_t> raw_key;
EXPECT_EQ(Status::Success(),
ExportKey(blink::WebCryptoKeyFormatRaw, key, &raw_key));
EXPECT_BYTES_EQ(test_key, raw_key);
// Test encryption.
std::vector<uint8_t> cipher_text;
std::vector<uint8_t> authentication_tag;
EXPECT_EQ(
Status::Success(),
AesGcmEncrypt(key, test_iv, test_additional_data, test_tag_size_bits,
test_plain_text, &cipher_text, &authentication_tag));
EXPECT_BYTES_EQ(test_cipher_text, cipher_text);
EXPECT_BYTES_EQ(test_authentication_tag, authentication_tag);
// Test decryption.
std::vector<uint8_t> plain_text;
EXPECT_EQ(
Status::Success(),
AesGcmDecrypt(key, test_iv, test_additional_data, test_tag_size_bits,
test_cipher_text, test_authentication_tag, &plain_text));
EXPECT_BYTES_EQ(test_plain_text, plain_text);
// Decryption should fail if any of the inputs are tampered with.
EXPECT_EQ(Status::OperationError(),
AesGcmDecrypt(key, Corrupted(test_iv), test_additional_data,
test_tag_size_bits, test_cipher_text,
test_authentication_tag, &plain_text));
EXPECT_EQ(Status::OperationError(),
AesGcmDecrypt(key, test_iv, Corrupted(test_additional_data),
test_tag_size_bits, test_cipher_text,
test_authentication_tag, &plain_text));
EXPECT_EQ(Status::OperationError(),
AesGcmDecrypt(key, test_iv, test_additional_data,
test_tag_size_bits, Corrupted(test_cipher_text),
test_authentication_tag, &plain_text));
EXPECT_EQ(Status::OperationError(),
AesGcmDecrypt(key, test_iv, test_additional_data,
test_tag_size_bits, test_cipher_text,
Corrupted(test_authentication_tag), &plain_text));
// Try different incorrect tag lengths
uint8_t kAlternateTagLengths[] = {0, 8, 96, 120, 128, 160, 255};
for (size_t tag_i = 0; tag_i < arraysize(kAlternateTagLengths); ++tag_i) {
unsigned int wrong_tag_size_bits = kAlternateTagLengths[tag_i];
if (test_tag_size_bits == wrong_tag_size_bits)
continue;
EXPECT_NE(Status::Success(),
AesGcmDecrypt(key, test_iv, test_additional_data,
wrong_tag_size_bits, test_cipher_text,
test_authentication_tag, &plain_text));
}
}
}
} // namespace
} // namespace webcrypto
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