cryptohome/vault_keyset_unittest.cc

// Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Unit tests for VaultKeyset.

#include "cryptohome/vault_keyset.h"

#include <string.h>  // For memcmp().

#include <base/files/file_path.h>
#include <base/logging.h>
#include <brillo/secure_blob.h>
#include <gmock/gmock.h>
#include <gtest/gtest.h>

#include "cryptohome/crypto.h"
#include "cryptohome/cryptohome_common.h"
#include "cryptohome/mock_platform.h"

namespace cryptohome {
using base::FilePath;
using brillo::SecureBlob;

using ::testing::_;
using ::testing::Return;
using ::testing::SaveArg;
using ::testing::SetArgPointee;
using ::testing::WithArg;

class VaultKeysetTest : public ::testing::Test {
 public:
  VaultKeysetTest() {}
  VaultKeysetTest(const VaultKeysetTest&) = delete;
  VaultKeysetTest& operator=(const VaultKeysetTest&) = delete;

  virtual ~VaultKeysetTest() {}

  static bool FindBlobInBlob(const brillo::SecureBlob& haystack,
                             const brillo::SecureBlob& needle) {
    if (needle.size() > haystack.size()) {
      return false;
    }
    for (unsigned int start = 0; start <= (haystack.size() - needle.size());
         start++) {
      if (memcmp(&haystack[start], needle.data(), needle.size()) == 0) {
        return true;
      }
    }
    return false;
  }

 protected:
  MockPlatform platform_;
};

TEST_F(VaultKeysetTest, AllocateRandom) {
  // Check that allocating a random VaultKeyset works
  Crypto crypto(&platform_);
  VaultKeyset vault_keyset;
  vault_keyset.Initialize(&platform_, &crypto);
  vault_keyset.CreateRandom();

  EXPECT_EQ(CRYPTOHOME_DEFAULT_KEY_SIZE, vault_keyset.GetFek().size());
  EXPECT_EQ(CRYPTOHOME_DEFAULT_KEY_SIGNATURE_SIZE,
            vault_keyset.GetFekSig().size());
  EXPECT_EQ(CRYPTOHOME_DEFAULT_KEY_SALT_SIZE, vault_keyset.GetFekSalt().size());

  EXPECT_EQ(CRYPTOHOME_DEFAULT_KEY_SIZE, vault_keyset.GetFnek().size());
  EXPECT_EQ(CRYPTOHOME_DEFAULT_KEY_SIGNATURE_SIZE,
            vault_keyset.GetFnekSig().size());
  EXPECT_EQ(CRYPTOHOME_DEFAULT_KEY_SALT_SIZE,
            vault_keyset.GetFnekSalt().size());
  EXPECT_EQ(CRYPTOHOME_CHAPS_KEY_LENGTH, vault_keyset.GetChapsKey().size());
}

TEST_F(VaultKeysetTest, SerializeTest) {
  // Check that serialize works
  Crypto crypto(&platform_);
  VaultKeyset vault_keyset;
  vault_keyset.Initialize(&platform_, &crypto);
  vault_keyset.CreateRandom();

  SecureBlob blob;
  EXPECT_TRUE(vault_keyset.ToKeysBlob(&blob));

  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(blob, vault_keyset.GetFek()));
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(blob, vault_keyset.GetFekSig()));
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(blob, vault_keyset.GetFekSalt()));

  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(blob, vault_keyset.GetFnek()));
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(blob, vault_keyset.GetFnekSig()));
  EXPECT_TRUE(
      VaultKeysetTest::FindBlobInBlob(blob, vault_keyset.GetFnekSalt()));
}

TEST_F(VaultKeysetTest, DeserializeTest) {
  // Check that deserialize works
  Crypto crypto(&platform_);
  VaultKeyset vault_keyset;
  vault_keyset.Initialize(&platform_, &crypto);
  vault_keyset.CreateRandom();

  SecureBlob blob;
  EXPECT_TRUE(vault_keyset.ToKeysBlob(&blob));

  VaultKeyset new_vault_keyset;
  new_vault_keyset.FromKeysBlob(blob);

  EXPECT_EQ(vault_keyset.GetFek().size(), new_vault_keyset.GetFek().size());
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(vault_keyset.GetFek(),
                                              new_vault_keyset.GetFek()));
  EXPECT_EQ(vault_keyset.GetFekSig().size(),
            new_vault_keyset.GetFekSig().size());
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(vault_keyset.GetFekSig(),
                                              new_vault_keyset.GetFekSig()));
  EXPECT_EQ(vault_keyset.GetFekSalt().size(),
            new_vault_keyset.GetFekSalt().size());
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(vault_keyset.GetFekSalt(),
                                              new_vault_keyset.GetFekSalt()));

  EXPECT_EQ(vault_keyset.GetFnek().size(), new_vault_keyset.GetFnek().size());
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(vault_keyset.GetFnek(),
                                              new_vault_keyset.GetFnek()));
  EXPECT_EQ(vault_keyset.GetFnekSig().size(),
            new_vault_keyset.GetFnekSig().size());
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(vault_keyset.GetFnekSig(),
                                              new_vault_keyset.GetFnekSig()));
  EXPECT_EQ(vault_keyset.GetFnekSalt().size(),
            new_vault_keyset.GetFnekSalt().size());
  EXPECT_TRUE(VaultKeysetTest::FindBlobInBlob(vault_keyset.GetFnekSalt(),
                                              new_vault_keyset.GetFnekSalt()));
}

ACTION_P(CopyToSecureBlob, b) {
  b->assign(arg0.begin(), arg0.end());
  return true;
}

ACTION_P(CopyFromSecureBlob, b) {
  arg0->assign(b->begin(), b->end());
  return true;
}

TEST_F(VaultKeysetTest, LoadSaveTest) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  keyset.CreateRandom();
  SecureBlob bytes;

  static const int kTestTimestamp = 123;
  static const int kFscryptPolicyVersion = 2;
  cryptohome::Timestamp timestamp;
  timestamp.set_timestamp(kTestTimestamp);
  SecureBlob tbytes(timestamp.ByteSizeLong());
  google::protobuf::uint8* buf =
      static_cast<google::protobuf::uint8*>(tbytes.data());
  timestamp.SerializeWithCachedSizesToArray(buf);

  keyset.SetFscryptPolicyVersion(kFscryptPolicyVersion);

  EXPECT_CALL(platform, WriteFileAtomicDurable(FilePath("foo"), _, _))
      .WillOnce(WithArg<1>(CopyToSecureBlob(&bytes)));
  EXPECT_CALL(platform, ReadFile(FilePath("foo"), _))
      .WillOnce(WithArg<1>(CopyFromSecureBlob(&bytes)));

  EXPECT_CALL(platform, ReadFile(FilePath("foo").AddExtension("timestamp"), _))
      .WillOnce(WithArg<1>(CopyFromSecureBlob(&tbytes)));

  SecureBlob key("key");
  EXPECT_TRUE(keyset.Encrypt(key, ""));
  EXPECT_TRUE(keyset.Save(FilePath("foo")));

  VaultKeyset new_keyset;
  new_keyset.Initialize(&platform, &crypto);
  EXPECT_TRUE(new_keyset.Load(FilePath("foo")));
  ASSERT_TRUE(new_keyset.HasLastActivityTimestamp());
  EXPECT_EQ(kTestTimestamp, new_keyset.GetLastActivityTimestamp());
  EXPECT_TRUE(new_keyset.Decrypt(key, false /* locked_to_single_user */,
                                 nullptr /* crypto_error */));
  EXPECT_EQ(new_keyset.GetFscryptPolicyVersion(), kFscryptPolicyVersion);
}

TEST_F(VaultKeysetTest, WriteError) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  keyset.CreateRandom();
  SecureBlob bytes;

  EXPECT_CALL(platform, WriteFileAtomicDurable(FilePath("foo"), _, _))
      .WillOnce(Return(false));

  SecureBlob key("key");
  EXPECT_TRUE(keyset.Encrypt(key, ""));
  EXPECT_FALSE(keyset.Save(FilePath("foo")));
}

TEST_F(VaultKeysetTest, AuthLockedDefault) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  static const int kFscryptPolicyVersion = 2;

  keyset.CreateRandom();
  keyset.SetFscryptPolicyVersion(kFscryptPolicyVersion);
  keyset.SetFlags(SerializedVaultKeyset::LE_CREDENTIAL);

  SecureBlob key("key");
  EXPECT_TRUE(keyset.Encrypt(key, ""));
  EXPECT_FALSE(keyset.GetAuthLocked());
}

TEST_F(VaultKeysetTest, GetPcrBoundAuthBlockStateTest) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  keyset.CreateRandom();
  keyset.SetFlags(SerializedVaultKeyset::TPM_WRAPPED |
                  SerializedVaultKeyset::SCRYPT_DERIVED |
                  SerializedVaultKeyset::PCR_BOUND);
  keyset.SetTpmPublicKeyHash(brillo::SecureBlob("yadayada"));
  keyset.SetTPMKey(brillo::SecureBlob("blabla"));
  keyset.SetExtendedTPMKey(brillo::SecureBlob("foobaz"));

  AuthBlockState auth_state;
  EXPECT_TRUE(keyset.GetAuthBlockState(&auth_state));

  EXPECT_TRUE(auth_state.has_tpm_bound_to_pcr_state());
  EXPECT_TRUE(auth_state.tpm_bound_to_pcr_state().scrypt_derived());
  EXPECT_TRUE(auth_state.tpm_bound_to_pcr_state().has_extended_tpm_key());
  EXPECT_TRUE(auth_state.tpm_bound_to_pcr_state().has_tpm_key());
}

TEST_F(VaultKeysetTest, GetNotPcrBoundAuthBlockState) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  keyset.CreateRandom();
  keyset.SetFlags(SerializedVaultKeyset::TPM_WRAPPED);
  keyset.SetTpmPublicKeyHash(brillo::SecureBlob("yadayada"));
  keyset.SetTPMKey(brillo::SecureBlob("blabla"));

  AuthBlockState auth_state;
  EXPECT_TRUE(keyset.GetAuthBlockState(&auth_state));

  EXPECT_TRUE(auth_state.has_tpm_not_bound_to_pcr_state());
  EXPECT_FALSE(auth_state.tpm_not_bound_to_pcr_state().scrypt_derived());
  EXPECT_TRUE(auth_state.tpm_not_bound_to_pcr_state().has_tpm_key());
}

TEST_F(VaultKeysetTest, GetPinWeaverAuthBlockState) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  const uint64_t le_label = 012345;
  keyset.CreateRandom();
  keyset.SetFlags(SerializedVaultKeyset::LE_CREDENTIAL);
  keyset.SetLELabel(le_label);

  AuthBlockState auth_state;
  EXPECT_TRUE(keyset.GetAuthBlockState(&auth_state));

  EXPECT_TRUE(auth_state.has_pin_weaver_state());
  EXPECT_TRUE(auth_state.pin_weaver_state().has_le_label());
  EXPECT_EQ(le_label, auth_state.pin_weaver_state().le_label());
}

TEST_F(VaultKeysetTest, GetChallengeCredentialAuthBlockState) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  keyset.CreateRandom();
  keyset.SetFlags(SerializedVaultKeyset::SCRYPT_WRAPPED |
                  SerializedVaultKeyset::SIGNATURE_CHALLENGE_PROTECTED);

  AuthBlockState auth_state;
  EXPECT_TRUE(keyset.GetAuthBlockState(&auth_state));

  EXPECT_TRUE(auth_state.has_challenge_credential_state());
}

TEST_F(VaultKeysetTest, GetLibscryptCompatAuthBlockState) {
  MockPlatform platform;
  Crypto crypto(&platform);
  VaultKeyset keyset;
  keyset.Initialize(&platform, &crypto);

  keyset.CreateRandom();
  keyset.SetFlags(SerializedVaultKeyset::SCRYPT_WRAPPED);

  AuthBlockState auth_state;
  EXPECT_TRUE(keyset.GetAuthBlockState(&auth_state));

  EXPECT_TRUE(auth_state.has_libscrypt_compat_state());
}

}  // namespace cryptohome