libcryfs/test/cryfs/config/crypto/CryConfigEncryptorTest.cpp
2017-12-03 19:01:41 +00:00

138 lines
5.2 KiB
C++

#include <gtest/gtest.h>
#include <cpp-utils/data/DataFixture.h>
#include <cpp-utils/crypto/symmetric/ciphers.h>
#include <cryfs/config/crypto/CryConfigEncryptor.h>
using std::ostream;
using cpputils::unique_ref;
using cpputils::make_unique_ref;
using cpputils::DataFixture;
using cpputils::Data;
using cpputils::FixedSizeData;
using cpputils::AES128_CFB;
using cpputils::AES256_GCM;
using cpputils::Twofish256_GCM;
using cpputils::Twofish128_CFB;
using cpputils::serialize;
using cpputils::deserialize;
using boost::none;
using namespace cryfs;
// This is needed for google test
namespace boost {
inline ostream &operator<<(ostream &stream, const CryConfigEncryptor::Decrypted &) {
return stream << "CryConfigEncryptor::Decrypted()";
}
}
#include <boost/optional/optional_io.hpp>
class CryConfigEncryptorTest: public ::testing::Test {
public:
unique_ref<CryConfigEncryptor> makeEncryptor() {
return make_unique_ref<CryConfigEncryptor>(_derivedKey(), _kdfParameters());
}
Data changeInnerCipherFieldTo(Data data, const string &newCipherName) {
InnerConfig innerConfig = _decryptInnerConfig(data);
innerConfig.cipherName = newCipherName;
return _encryptInnerConfig(innerConfig);
}
private:
FixedSizeData<CryConfigEncryptor::MaxTotalKeySize> _derivedKey() {
return DataFixture::generateFixedSize<CryConfigEncryptor::MaxTotalKeySize>(3);
}
Data _kdfParameters() {
return DataFixture::generate(128, 2);
}
unique_ref<OuterEncryptor> _outerEncryptor() {
auto outerKey = _derivedKey().take<CryConfigEncryptor::OuterKeySize>();
return make_unique_ref<OuterEncryptor>(outerKey, _kdfParameters());
}
InnerConfig _decryptInnerConfig(const Data &data) {
OuterConfig outerConfig = OuterConfig::deserialize(data).value();
Data serializedInnerConfig = _outerEncryptor()->decrypt(outerConfig).value();
return InnerConfig::deserialize(serializedInnerConfig).value();
}
Data _encryptInnerConfig(const InnerConfig &innerConfig) {
Data serializedInnerConfig = innerConfig.serialize();
OuterConfig outerConfig = _outerEncryptor()->encrypt(serializedInnerConfig);
return outerConfig.serialize();
}
};
TEST_F(CryConfigEncryptorTest, EncryptAndDecrypt_Data_AES) {
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(DataFixture::generate(400), AES256_GCM::NAME);
auto decrypted = encryptor->decrypt(encrypted).value();
EXPECT_EQ(DataFixture::generate(400), decrypted.data);
}
TEST_F(CryConfigEncryptorTest, EncryptAndDecrypt_Data_Twofish) {
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(DataFixture::generate(400), Twofish128_CFB::NAME);
auto decrypted = encryptor->decrypt(encrypted).value();
EXPECT_EQ(DataFixture::generate(400), decrypted.data);
}
TEST_F(CryConfigEncryptorTest, EncryptAndDecrypt_Cipher_AES) {
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(DataFixture::generate(400), AES256_GCM::NAME);
auto decrypted = encryptor->decrypt(encrypted).value();
EXPECT_EQ(AES256_GCM::NAME, decrypted.cipherName);
}
TEST_F(CryConfigEncryptorTest, EncryptAndDecrypt_Cipher_Twofish) {
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(DataFixture::generate(400), Twofish128_CFB::NAME);
auto decrypted = encryptor->decrypt(encrypted).value();
EXPECT_EQ(Twofish128_CFB::NAME, decrypted.cipherName);
}
TEST_F(CryConfigEncryptorTest, EncryptAndDecrypt_EmptyData) {
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(Data(0), AES256_GCM::NAME);
auto decrypted = encryptor->decrypt(encrypted).value();
EXPECT_EQ(Data(0), decrypted.data);
}
TEST_F(CryConfigEncryptorTest, InvalidCiphertext) {
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(DataFixture::generate(400), AES256_GCM::NAME);
serialize<uint8_t>(encrypted.data(), deserialize<uint8_t>(encrypted.data()) + 1); //Modify ciphertext
auto decrypted = encryptor->decrypt(encrypted);
EXPECT_EQ(none, decrypted);
}
TEST_F(CryConfigEncryptorTest, DoesntEncryptWhenTooLarge) {
auto encryptor = makeEncryptor();
EXPECT_THROW(
encryptor->encrypt(DataFixture::generate(2000), AES256_GCM::NAME),
std::runtime_error
);
}
TEST_F(CryConfigEncryptorTest, EncryptionIsFixedSize) {
auto encryptor = makeEncryptor();
Data encrypted1 = encryptor->encrypt(DataFixture::generate(100), AES128_CFB::NAME);
Data encrypted2 = encryptor->encrypt(DataFixture::generate(200), Twofish256_GCM::NAME);
Data encrypted3 = encryptor->encrypt(Data(0), AES256_GCM::NAME);
EXPECT_EQ(encrypted1.size(), encrypted2.size());
EXPECT_EQ(encrypted1.size(), encrypted3.size());
}
TEST_F(CryConfigEncryptorTest, SpecifiedInnerCipherIsUsed) {
//Tests that it can't be decrypted if the inner cipher field stores the wrong cipher
auto encryptor = makeEncryptor();
Data encrypted = encryptor->encrypt(DataFixture::generate(400), AES256_GCM::NAME);
encrypted = changeInnerCipherFieldTo(std::move(encrypted), Twofish256_GCM::NAME);
auto decrypted = encryptor->decrypt(encrypted);
EXPECT_EQ(none, decrypted);
}