crypto/encryptor_unittest.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "crypto/encryptor.h"
   6
   7 #include <string>
   8
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "crypto/symmetric_key.h"
  12 #include "testing/gtest/include/gtest/gtest.h"
  13
  14 TEST(EncryptorTest, EncryptDecrypt) {
  15   scoped_ptr<crypto::SymmetricKey> key(
  16       crypto::SymmetricKey::DeriveKeyFromPassword(
  17           crypto::SymmetricKey::AES, "password", "saltiest", 1000, 256));
  18   EXPECT_TRUE(key.get());
  19
  20   crypto::Encryptor encryptor;
  21   // The IV must be exactly as long as the cipher block size.
  22   std::string iv("the iv: 16 bytes");
  23   EXPECT_EQ(16U, iv.size());
  24   EXPECT_TRUE(encryptor.Init(key.get(), crypto::Encryptor::CBC, iv));
  25
  26   std::string plaintext("this is the plaintext");
  27   std::string ciphertext;
  28   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
  29
  30   EXPECT_LT(0U, ciphertext.size());
  31
  32   std::string decrypted;
  33   EXPECT_TRUE(encryptor.Decrypt(ciphertext, &decrypted));
  34
  35   EXPECT_EQ(plaintext, decrypted);
  36 }
  37
  38 TEST(EncryptorTest, DecryptWrongKey) {
  39   scoped_ptr<crypto::SymmetricKey> key(
  40       crypto::SymmetricKey::DeriveKeyFromPassword(
  41           crypto::SymmetricKey::AES, "password", "saltiest", 1000, 256));
  42   EXPECT_TRUE(key.get());
  43
  44   // A wrong key that can be detected by implementations that validate every
  45   // byte in the padding.
  46   scoped_ptr<crypto::SymmetricKey> wrong_key(
  47         crypto::SymmetricKey::DeriveKeyFromPassword(
  48             crypto::SymmetricKey::AES, "wrongword", "sweetest", 1000, 256));
  49   EXPECT_TRUE(wrong_key.get());
  50
  51   // A wrong key that can't be detected by any implementation.  The password
  52   // "wrongword;" would also work.
  53   scoped_ptr<crypto::SymmetricKey> wrong_key2(
  54         crypto::SymmetricKey::DeriveKeyFromPassword(
  55             crypto::SymmetricKey::AES, "wrongword+", "sweetest", 1000, 256));
  56   EXPECT_TRUE(wrong_key2.get());
  57
  58   // A wrong key that can be detected by all implementations.
  59   scoped_ptr<crypto::SymmetricKey> wrong_key3(
  60         crypto::SymmetricKey::DeriveKeyFromPassword(
  61             crypto::SymmetricKey::AES, "wrongwordx", "sweetest", 1000, 256));
  62   EXPECT_TRUE(wrong_key3.get());
  63
  64   crypto::Encryptor encryptor;
  65   // The IV must be exactly as long as the cipher block size.
  66   std::string iv("the iv: 16 bytes");
  67   EXPECT_EQ(16U, iv.size());
  68   EXPECT_TRUE(encryptor.Init(key.get(), crypto::Encryptor::CBC, iv));
  69
  70   std::string plaintext("this is the plaintext");
  71   std::string ciphertext;
  72   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
  73
  74   static const unsigned char expected_ciphertext[] = {
  75     0x7D, 0x67, 0x5B, 0x53, 0xE6, 0xD8, 0x0F, 0x27,
  76     0x74, 0xB1, 0x90, 0xFE, 0x6E, 0x58, 0x4A, 0xA0,
  77     0x0E, 0x35, 0xE3, 0x01, 0xC0, 0xFE, 0x9A, 0xD8,
  78     0x48, 0x1D, 0x42, 0xB0, 0xBA, 0x21, 0xB2, 0x0C
  79   };
  80
  81   ASSERT_EQ(arraysize(expected_ciphertext), ciphertext.size());
  82   for (size_t i = 0; i < ciphertext.size(); ++i) {
  83     ASSERT_EQ(expected_ciphertext[i],
  84               static_cast<unsigned char>(ciphertext[i]));
  85   }
  86
  87   std::string decrypted;
  88
  89   // This wrong key causes the last padding byte to be 5, which is a valid
  90   // padding length, and the second to last padding byte to be 137, which is
  91   // invalid.  If an implementation simply uses the last padding byte to
  92   // determine the padding length without checking every padding byte,
  93   // Encryptor::Decrypt() will still return true.  This is the case for NSS
  94   // (crbug.com/124434).
  95 #if !defined(USE_NSS_CERTS) && !defined(OS_WIN) && !defined(OS_MACOSX)
  96   crypto::Encryptor decryptor;
  97   EXPECT_TRUE(decryptor.Init(wrong_key.get(), crypto::Encryptor::CBC, iv));
  98   EXPECT_FALSE(decryptor.Decrypt(ciphertext, &decrypted));
  99 #endif
 100
 101   // This demonstrates that not all wrong keys can be detected by padding
 102   // error. This wrong key causes the last padding byte to be 1, which is
 103   // a valid padding block of length 1.
 104   crypto::Encryptor decryptor2;
 105   EXPECT_TRUE(decryptor2.Init(wrong_key2.get(), crypto::Encryptor::CBC, iv));
 106   EXPECT_TRUE(decryptor2.Decrypt(ciphertext, &decrypted));
 107
 108   // This wrong key causes the last padding byte to be 253, which should be
 109   // rejected by all implementations.
 110   crypto::Encryptor decryptor3;
 111   EXPECT_TRUE(decryptor3.Init(wrong_key3.get(), crypto::Encryptor::CBC, iv));
 112   EXPECT_FALSE(decryptor3.Decrypt(ciphertext, &decrypted));
 113 }
 114
 115 namespace {
 116
 117 // From NIST SP 800-38a test cast:
 118 // - F.5.1 CTR-AES128.Encrypt
 119 // - F.5.6 CTR-AES256.Encrypt
 120 // http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf
 121 const unsigned char kAES128CTRKey[] = {
 122   0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6,
 123   0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c
 124 };
 125
 126 const unsigned char kAES256CTRKey[] = {
 127   0x60, 0x3d, 0xeb, 0x10, 0x15, 0xca, 0x71, 0xbe,
 128   0x2b, 0x73, 0xae, 0xf0, 0x85, 0x7d, 0x77, 0x81,
 129   0x1f, 0x35, 0x2c, 0x07, 0x3b, 0x61, 0x08, 0xd7,
 130   0x2d, 0x98, 0x10, 0xa3, 0x09, 0x14, 0xdf, 0xf4
 131 };
 132
 133 const unsigned char kAESCTRInitCounter[] = {
 134   0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
 135   0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
 136 };
 137
 138 const unsigned char kAESCTRPlaintext[] = {
 139   // Block #1
 140   0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
 141   0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
 142   // Block #2
 143   0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
 144   0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
 145   // Block #3
 146   0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11,
 147   0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
 148   // Block #4
 149   0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17,
 150   0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10
 151 };
 152
 153 const unsigned char kAES128CTRCiphertext[] = {
 154   // Block #1
 155   0x87, 0x4d, 0x61, 0x91, 0xb6, 0x20, 0xe3, 0x26,
 156   0x1b, 0xef, 0x68, 0x64, 0x99, 0x0d, 0xb6, 0xce,
 157   // Block #2
 158   0x98, 0x06, 0xf6, 0x6b, 0x79, 0x70, 0xfd, 0xff,
 159   0x86, 0x17, 0x18, 0x7b, 0xb9, 0xff, 0xfd, 0xff,
 160   // Block #3
 161   0x5a, 0xe4, 0xdf, 0x3e, 0xdb, 0xd5, 0xd3, 0x5e,
 162   0x5b, 0x4f, 0x09, 0x02, 0x0d, 0xb0, 0x3e, 0xab,
 163   // Block #4
 164   0x1e, 0x03, 0x1d, 0xda, 0x2f, 0xbe, 0x03, 0xd1,
 165   0x79, 0x21, 0x70, 0xa0, 0xf3, 0x00, 0x9c, 0xee
 166 };
 167
 168 const unsigned char kAES256CTRCiphertext[] = {
 169   // Block #1
 170   0x60, 0x1e, 0xc3, 0x13, 0x77, 0x57, 0x89, 0xa5,
 171   0xb7, 0xa7, 0xf5, 0x04, 0xbb, 0xf3, 0xd2, 0x28,
 172   // Block #2
 173   0xf4, 0x43, 0xe3, 0xca, 0x4d, 0x62, 0xb5, 0x9a,
 174   0xca, 0x84, 0xe9, 0x90, 0xca, 0xca, 0xf5, 0xc5,
 175   // Block #3
 176   0x2b, 0x09, 0x30, 0xda, 0xa2, 0x3d, 0xe9, 0x4c,
 177   0xe8, 0x70, 0x17, 0xba, 0x2d, 0x84, 0x98, 0x8d,
 178   // Block #4
 179   0xdf, 0xc9, 0xc5, 0x8d, 0xb6, 0x7a, 0xad, 0xa6,
 180   0x13, 0xc2, 0xdd, 0x08, 0x45, 0x79, 0x41, 0xa6
 181 };
 182
 183 void TestAESCTREncrypt(
 184     const unsigned char* key, size_t key_size,
 185     const unsigned char* init_counter, size_t init_counter_size,
 186     const unsigned char* plaintext, size_t plaintext_size,
 187     const unsigned char* ciphertext, size_t ciphertext_size) {
 188   std::string key_str(reinterpret_cast<const char*>(key), key_size);
 189   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 190       crypto::SymmetricKey::AES, key_str));
 191   ASSERT_TRUE(sym_key.get());
 192
 193   crypto::Encryptor encryptor;
 194   EXPECT_TRUE(encryptor.Init(sym_key.get(), crypto::Encryptor::CTR, ""));
 195
 196   base::StringPiece init_counter_str(
 197       reinterpret_cast<const char*>(init_counter), init_counter_size);
 198   base::StringPiece plaintext_str(
 199       reinterpret_cast<const char*>(plaintext), plaintext_size);
 200
 201   EXPECT_TRUE(encryptor.SetCounter(init_counter_str));
 202   std::string encrypted;
 203   EXPECT_TRUE(encryptor.Encrypt(plaintext_str, &encrypted));
 204
 205   EXPECT_EQ(ciphertext_size, encrypted.size());
 206   EXPECT_EQ(0, memcmp(encrypted.data(), ciphertext, encrypted.size()));
 207
 208   std::string decrypted;
 209   EXPECT_TRUE(encryptor.SetCounter(init_counter_str));
 210   EXPECT_TRUE(encryptor.Decrypt(encrypted, &decrypted));
 211
 212   EXPECT_EQ(plaintext_str, decrypted);
 213 }
 214
 215 void TestAESCTRMultipleDecrypt(
 216     const unsigned char* key, size_t key_size,
 217     const unsigned char* init_counter, size_t init_counter_size,
 218     const unsigned char* plaintext, size_t plaintext_size,
 219     const unsigned char* ciphertext, size_t ciphertext_size) {
 220   std::string key_str(reinterpret_cast<const char*>(key), key_size);
 221   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 222       crypto::SymmetricKey::AES, key_str));
 223   ASSERT_TRUE(sym_key.get());
 224
 225   crypto::Encryptor encryptor;
 226   EXPECT_TRUE(encryptor.Init(sym_key.get(), crypto::Encryptor::CTR, ""));
 227
 228   // Counter is set only once.
 229   EXPECT_TRUE(encryptor.SetCounter(base::StringPiece(
 230       reinterpret_cast<const char*>(init_counter), init_counter_size)));
 231
 232   std::string ciphertext_str(reinterpret_cast<const char*>(ciphertext),
 233                              ciphertext_size);
 234
 235   int kTestDecryptSizes[] = { 32, 16, 8 };
 236
 237   int offset = 0;
 238   for (size_t i = 0; i < arraysize(kTestDecryptSizes); ++i) {
 239     std::string decrypted;
 240     size_t len = kTestDecryptSizes[i];
 241     EXPECT_TRUE(
 242         encryptor.Decrypt(ciphertext_str.substr(offset, len), &decrypted));
 243     EXPECT_EQ(len, decrypted.size());
 244     EXPECT_EQ(0, memcmp(decrypted.data(), plaintext + offset, len));
 245     offset += len;
 246   }
 247 }
 248
 249 }  // namespace
 250
 251 TEST(EncryptorTest, EncryptAES128CTR) {
 252   TestAESCTREncrypt(
 253       kAES128CTRKey, arraysize(kAES128CTRKey),
 254       kAESCTRInitCounter, arraysize(kAESCTRInitCounter),
 255       kAESCTRPlaintext, arraysize(kAESCTRPlaintext),
 256       kAES128CTRCiphertext, arraysize(kAES128CTRCiphertext));
 257 }
 258
 259 TEST(EncryptorTest, EncryptAES256CTR) {
 260   TestAESCTREncrypt(
 261       kAES256CTRKey, arraysize(kAES256CTRKey),
 262       kAESCTRInitCounter, arraysize(kAESCTRInitCounter),
 263       kAESCTRPlaintext, arraysize(kAESCTRPlaintext),
 264       kAES256CTRCiphertext, arraysize(kAES256CTRCiphertext));
 265 }
 266
 267 TEST(EncryptorTest, EncryptAES128CTR_MultipleDecrypt) {
 268   TestAESCTRMultipleDecrypt(
 269       kAES128CTRKey, arraysize(kAES128CTRKey),
 270       kAESCTRInitCounter, arraysize(kAESCTRInitCounter),
 271       kAESCTRPlaintext, arraysize(kAESCTRPlaintext),
 272       kAES128CTRCiphertext, arraysize(kAES128CTRCiphertext));
 273 }
 274
 275 TEST(EncryptorTest, EncryptAES256CTR_MultipleDecrypt) {
 276   TestAESCTRMultipleDecrypt(
 277       kAES256CTRKey, arraysize(kAES256CTRKey),
 278       kAESCTRInitCounter, arraysize(kAESCTRInitCounter),
 279       kAESCTRPlaintext, arraysize(kAESCTRPlaintext),
 280       kAES256CTRCiphertext, arraysize(kAES256CTRCiphertext));
 281 }
 282
 283 TEST(EncryptorTest, EncryptDecryptCTR) {
 284   scoped_ptr<crypto::SymmetricKey> key(
 285       crypto::SymmetricKey::GenerateRandomKey(crypto::SymmetricKey::AES, 128));
 286
 287   EXPECT_TRUE(key.get());
 288   const std::string kInitialCounter = "0000000000000000";
 289
 290   crypto::Encryptor encryptor;
 291   EXPECT_TRUE(encryptor.Init(key.get(), crypto::Encryptor::CTR, ""));
 292   EXPECT_TRUE(encryptor.SetCounter(kInitialCounter));
 293
 294   std::string plaintext("normal plaintext of random length");
 295   std::string ciphertext;
 296   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
 297   EXPECT_LT(0U, ciphertext.size());
 298
 299   std::string decrypted;
 300   EXPECT_TRUE(encryptor.SetCounter(kInitialCounter));
 301   EXPECT_TRUE(encryptor.Decrypt(ciphertext, &decrypted));
 302   EXPECT_EQ(plaintext, decrypted);
 303
 304   plaintext = "0123456789012345";
 305   EXPECT_TRUE(encryptor.SetCounter(kInitialCounter));
 306   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
 307   EXPECT_LT(0U, ciphertext.size());
 308
 309   EXPECT_TRUE(encryptor.SetCounter(kInitialCounter));
 310   EXPECT_TRUE(encryptor.Decrypt(ciphertext, &decrypted));
 311   EXPECT_EQ(plaintext, decrypted);
 312 }
 313
 314 TEST(EncryptorTest, CTRCounter) {
 315   const int kCounterSize = 16;
 316   const unsigned char kTest1[] =
 317       {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 318   unsigned char buf[16];
 319
 320   // Increment 10 times.
 321   crypto::Encryptor::Counter counter1(
 322       std::string(reinterpret_cast<const char*>(kTest1), kCounterSize));
 323   for (int i = 0; i < 10; ++i)
 324     counter1.Increment();
 325   counter1.Write(buf);
 326   EXPECT_EQ(0, memcmp(buf, kTest1, 15));
 327   EXPECT_TRUE(buf[15] == 10);
 328
 329   // Check corner cases.
 330   const unsigned char kTest2[] = {
 331       0, 0, 0, 0, 0, 0, 0, 0,
 332       0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 333   };
 334   const unsigned char kExpect2[] =
 335       {0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0};
 336   crypto::Encryptor::Counter counter2(
 337       std::string(reinterpret_cast<const char*>(kTest2), kCounterSize));
 338   counter2.Increment();
 339   counter2.Write(buf);
 340   EXPECT_EQ(0, memcmp(buf, kExpect2, kCounterSize));
 341
 342   const unsigned char kTest3[] = {
 343       0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
 344       0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
 345   };
 346   const unsigned char kExpect3[] =
 347       {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 348   crypto::Encryptor::Counter counter3(
 349       std::string(reinterpret_cast<const char*>(kTest3), kCounterSize));
 350   counter3.Increment();
 351   counter3.Write(buf);
 352   EXPECT_EQ(0, memcmp(buf, kExpect3, kCounterSize));
 353 }
 354
 355 // TODO(wtc): add more known-answer tests.  Test vectors are available from
 356 // http://www.ietf.org/rfc/rfc3602
 357 // http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf
 358 // http://gladman.plushost.co.uk/oldsite/AES/index.php
 359 // http://csrc.nist.gov/groups/STM/cavp/documents/aes/KAT_AES.zip
 360
 361 // NIST SP 800-38A test vector F.2.5 CBC-AES256.Encrypt.
 362 TEST(EncryptorTest, EncryptAES256CBC) {
 363   // From NIST SP 800-38a test cast F.2.5 CBC-AES256.Encrypt.
 364   static const unsigned char kRawKey[] = {
 365     0x60, 0x3d, 0xeb, 0x10, 0x15, 0xca, 0x71, 0xbe,
 366     0x2b, 0x73, 0xae, 0xf0, 0x85, 0x7d, 0x77, 0x81,
 367     0x1f, 0x35, 0x2c, 0x07, 0x3b, 0x61, 0x08, 0xd7,
 368     0x2d, 0x98, 0x10, 0xa3, 0x09, 0x14, 0xdf, 0xf4
 369   };
 370   static const unsigned char kRawIv[] = {
 371     0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
 372     0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
 373   };
 374   static const unsigned char kRawPlaintext[] = {
 375     // Block #1
 376     0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
 377     0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
 378     // Block #2
 379     0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
 380     0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
 381     // Block #3
 382     0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11,
 383     0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
 384     // Block #4
 385     0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17,
 386     0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10,
 387   };
 388   static const unsigned char kRawCiphertext[] = {
 389     // Block #1
 390     0xf5, 0x8c, 0x4c, 0x04, 0xd6, 0xe5, 0xf1, 0xba,
 391     0x77, 0x9e, 0xab, 0xfb, 0x5f, 0x7b, 0xfb, 0xd6,
 392     // Block #2
 393     0x9c, 0xfc, 0x4e, 0x96, 0x7e, 0xdb, 0x80, 0x8d,
 394     0x67, 0x9f, 0x77, 0x7b, 0xc6, 0x70, 0x2c, 0x7d,
 395     // Block #3
 396     0x39, 0xf2, 0x33, 0x69, 0xa9, 0xd9, 0xba, 0xcf,
 397     0xa5, 0x30, 0xe2, 0x63, 0x04, 0x23, 0x14, 0x61,
 398     // Block #4
 399     0xb2, 0xeb, 0x05, 0xe2, 0xc3, 0x9b, 0xe9, 0xfc,
 400     0xda, 0x6c, 0x19, 0x07, 0x8c, 0x6a, 0x9d, 0x1b,
 401     // PKCS #5 padding, encrypted.
 402     0x3f, 0x46, 0x17, 0x96, 0xd6, 0xb0, 0xd6, 0xb2,
 403     0xe0, 0xc2, 0xa7, 0x2b, 0x4d, 0x80, 0xe6, 0x44
 404   };
 405
 406   std::string key(reinterpret_cast<const char*>(kRawKey), sizeof(kRawKey));
 407   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 408       crypto::SymmetricKey::AES, key));
 409   ASSERT_TRUE(sym_key.get());
 410
 411   crypto::Encryptor encryptor;
 412   // The IV must be exactly as long a the cipher block size.
 413   std::string iv(reinterpret_cast<const char*>(kRawIv), sizeof(kRawIv));
 414   EXPECT_EQ(16U, iv.size());
 415   EXPECT_TRUE(encryptor.Init(sym_key.get(), crypto::Encryptor::CBC, iv));
 416
 417   std::string plaintext(reinterpret_cast<const char*>(kRawPlaintext),
 418                         sizeof(kRawPlaintext));
 419   std::string ciphertext;
 420   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
 421
 422   EXPECT_EQ(sizeof(kRawCiphertext), ciphertext.size());
 423   EXPECT_EQ(0, memcmp(ciphertext.data(), kRawCiphertext, ciphertext.size()));
 424
 425   std::string decrypted;
 426   EXPECT_TRUE(encryptor.Decrypt(ciphertext, &decrypted));
 427
 428   EXPECT_EQ(plaintext, decrypted);
 429 }
 430
 431 // Expected output derived from the NSS implementation.
 432 TEST(EncryptorTest, EncryptAES128CBCRegression) {
 433   std::string key = "128=SixteenBytes";
 434   std::string iv = "Sweet Sixteen IV";
 435   std::string plaintext = "Plain text with a g-clef U+1D11E \360\235\204\236";
 436   std::string expected_ciphertext_hex =
 437       "D4A67A0BA33C30F207344D81D1E944BBE65587C3D7D9939A"
 438       "C070C62B9C15A3EA312EA4AD1BC7929F4D3C16B03AD5ADA8";
 439
 440   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 441       crypto::SymmetricKey::AES, key));
 442   ASSERT_TRUE(sym_key.get());
 443
 444   crypto::Encryptor encryptor;
 445   // The IV must be exactly as long a the cipher block size.
 446   EXPECT_EQ(16U, iv.size());
 447   EXPECT_TRUE(encryptor.Init(sym_key.get(), crypto::Encryptor::CBC, iv));
 448
 449   std::string ciphertext;
 450   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
 451   EXPECT_EQ(expected_ciphertext_hex, base::HexEncode(ciphertext.data(),
 452                                                      ciphertext.size()));
 453
 454   std::string decrypted;
 455   EXPECT_TRUE(encryptor.Decrypt(ciphertext, &decrypted));
 456   EXPECT_EQ(plaintext, decrypted);
 457 }
 458
 459 // Symmetric keys with an unsupported size should be rejected. Whether they are
 460 // rejected by SymmetricKey::Import or Encryptor::Init depends on the platform.
 461 TEST(EncryptorTest, UnsupportedKeySize) {
 462   std::string key = "7 = bad";
 463   std::string iv = "Sweet Sixteen IV";
 464   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 465       crypto::SymmetricKey::AES, key));
 466   if (!sym_key.get())
 467     return;
 468
 469   crypto::Encryptor encryptor;
 470   // The IV must be exactly as long as the cipher block size.
 471   EXPECT_EQ(16U, iv.size());
 472   EXPECT_FALSE(encryptor.Init(sym_key.get(), crypto::Encryptor::CBC, iv));
 473 }
 474
 475 TEST(EncryptorTest, UnsupportedIV) {
 476   std::string key = "128=SixteenBytes";
 477   std::string iv = "OnlyForteen :(";
 478   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 479       crypto::SymmetricKey::AES, key));
 480   ASSERT_TRUE(sym_key.get());
 481
 482   crypto::Encryptor encryptor;
 483   EXPECT_FALSE(encryptor.Init(sym_key.get(), crypto::Encryptor::CBC, iv));
 484 }
 485
 486 TEST(EncryptorTest, EmptyEncrypt) {
 487   std::string key = "128=SixteenBytes";
 488   std::string iv = "Sweet Sixteen IV";
 489   std::string plaintext;
 490   std::string expected_ciphertext_hex = "8518B8878D34E7185E300D0FCC426396";
 491
 492   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 493       crypto::SymmetricKey::AES, key));
 494   ASSERT_TRUE(sym_key.get());
 495
 496   crypto::Encryptor encryptor;
 497   // The IV must be exactly as long a the cipher block size.
 498   EXPECT_EQ(16U, iv.size());
 499   EXPECT_TRUE(encryptor.Init(sym_key.get(), crypto::Encryptor::CBC, iv));
 500
 501   std::string ciphertext;
 502   EXPECT_TRUE(encryptor.Encrypt(plaintext, &ciphertext));
 503   EXPECT_EQ(expected_ciphertext_hex, base::HexEncode(ciphertext.data(),
 504                                                      ciphertext.size()));
 505 }
 506
 507 TEST(EncryptorTest, CipherTextNotMultipleOfBlockSize) {
 508   std::string key = "128=SixteenBytes";
 509   std::string iv = "Sweet Sixteen IV";
 510
 511   scoped_ptr<crypto::SymmetricKey> sym_key(crypto::SymmetricKey::Import(
 512       crypto::SymmetricKey::AES, key));
 513   ASSERT_TRUE(sym_key.get());
 514
 515   crypto::Encryptor encryptor;
 516   // The IV must be exactly as long a the cipher block size.
 517   EXPECT_EQ(16U, iv.size());
 518   EXPECT_TRUE(encryptor.Init(sym_key.get(), crypto::Encryptor::CBC, iv));
 519
 520   // Use a separately allocated array to improve the odds of the memory tools
 521   // catching invalid accesses.
 522   //
 523   // Otherwise when using std::string as the other tests do, accesses several
 524   // bytes off the end of the buffer may fall inside the reservation of
 525   // the string and not be detected.
 526   scoped_ptr<char[]> ciphertext(new char[1]);
 527
 528   std::string plaintext;
 529   EXPECT_FALSE(
 530       encryptor.Decrypt(base::StringPiece(ciphertext.get(), 1), &plaintext));
 531 }