content/child/webcrypto/test/aes_ctr_unittest.cc

   1 // Copyright 2014 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 "base/stl_util.h"
   6 #include "content/child/webcrypto/algorithm_dispatch.h"
   7 #include "content/child/webcrypto/crypto_data.h"
   8 #include "content/child/webcrypto/status.h"
   9 #include "content/child/webcrypto/test/test_helpers.h"
  10 #include "content/child/webcrypto/webcrypto_util.h"
  11 #include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
  12 #include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
  13
  14 namespace content {
  15
  16 namespace webcrypto {
  17
  18 namespace {
  19
  20 bool SupportsAesCtr() {
  21 #if defined(USE_OPENSSL)
  22   return true;
  23 #else
  24   return false;
  25 #endif
  26 }
  27
  28 // Creates an AES-CTR algorithm for encryption/decryption.
  29 blink::WebCryptoAlgorithm CreateAesCtrAlgorithm(
  30     const std::vector<uint8_t>& counter,
  31     uint8_t length_bits) {
  32   return blink::WebCryptoAlgorithm::adoptParamsAndCreate(
  33       blink::WebCryptoAlgorithmIdAesCtr,
  34       new blink::WebCryptoAesCtrParams(length_bits, vector_as_array(&counter),
  35                                        counter.size()));
  36 }
  37
  38 TEST(WebCryptoAesCtrTest, EncryptDecryptKnownAnswer) {
  39   if (!SupportsAesCtr()) {
  40     LOG(WARNING) << "Skipping test because AES-CTR is not supported";
  41     return;
  42   }
  43
  44   scoped_ptr<base::ListValue> tests;
  45   ASSERT_TRUE(ReadJsonTestFileToList("aes_ctr.json", &tests));
  46
  47   for (size_t test_index = 0; test_index < tests->GetSize(); ++test_index) {
  48     SCOPED_TRACE(test_index);
  49     base::DictionaryValue* test;
  50     ASSERT_TRUE(tests->GetDictionary(test_index, &test));
  51
  52     std::vector<uint8_t> test_key = GetBytesFromHexString(test, "key");
  53     std::vector<uint8_t> test_counter = GetBytesFromHexString(test, "counter");
  54     int counter_length_bits = 0;
  55     ASSERT_TRUE(test->GetInteger("length", &counter_length_bits));
  56
  57     std::vector<uint8_t> test_plain_text =
  58         GetBytesFromHexString(test, "plain_text");
  59     std::vector<uint8_t> test_cipher_text =
  60         GetBytesFromHexString(test, "cipher_text");
  61
  62     blink::WebCryptoKey key = ImportSecretKeyFromRaw(
  63         test_key, CreateAlgorithm(blink::WebCryptoAlgorithmIdAesCtr),
  64         blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageDecrypt);
  65
  66     EXPECT_EQ(test_key.size() * 8, key.algorithm().aesParams()->lengthBits());
  67
  68     std::vector<uint8_t> output;
  69
  70     // Test encryption.
  71     EXPECT_EQ(Status::Success(),
  72               Encrypt(CreateAesCtrAlgorithm(test_counter, counter_length_bits),
  73                       key, CryptoData(test_plain_text), &output));
  74     EXPECT_BYTES_EQ(test_cipher_text, output);
  75
  76     // Test decryption.
  77     EXPECT_EQ(Status::Success(),
  78               Decrypt(CreateAesCtrAlgorithm(test_counter, counter_length_bits),
  79                       key, CryptoData(test_cipher_text), &output));
  80     EXPECT_BYTES_EQ(test_plain_text, output);
  81   }
  82 }
  83
  84 // The counter block must be exactly 16 bytes.
  85 TEST(WebCryptoAesCtrTest, InvalidCounterBlockLength) {
  86   if (!SupportsAesCtr()) {
  87     LOG(WARNING) << "Skipping test because AES-CTR is not supported";
  88     return;
  89   }
  90
  91   const unsigned int kBadCounterBlockLengthBytes[] = {0, 15, 17};
  92
  93   blink::WebCryptoKey key = ImportSecretKeyFromRaw(
  94       std::vector<uint8>(16),  // 128-bit key of all zeros.
  95       CreateAlgorithm(blink::WebCryptoAlgorithmIdAesCtr),
  96       blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageDecrypt);
  97
  98   std::vector<uint8_t> input(32);
  99   std::vector<uint8_t> output;
 100
 101   for (size_t i = 0; i < arraysize(kBadCounterBlockLengthBytes); ++i) {
 102     std::vector<uint8_t> bad_counter(kBadCounterBlockLengthBytes[i]);
 103
 104     EXPECT_EQ(Status::ErrorIncorrectSizeAesCtrCounter(),
 105               Encrypt(CreateAesCtrAlgorithm(bad_counter, 128), key,
 106                       CryptoData(input), &output));
 107
 108     EXPECT_EQ(Status::ErrorIncorrectSizeAesCtrCounter(),
 109               Decrypt(CreateAesCtrAlgorithm(bad_counter, 128), key,
 110                       CryptoData(input), &output));
 111   }
 112 }
 113
 114 // The counter length cannot be less than 1 or greater than 128.
 115 TEST(WebCryptoAesCtrTest, InvalidCounterLength) {
 116   if (!SupportsAesCtr()) {
 117     LOG(WARNING) << "Skipping test because AES-CTR is not supported";
 118     return;
 119   }
 120
 121   const uint8_t kBadCounterLengthBits[] = {0, 129};
 122
 123   blink::WebCryptoKey key = ImportSecretKeyFromRaw(
 124       std::vector<uint8>(16),  // 128-bit key of all zeros.
 125       CreateAlgorithm(blink::WebCryptoAlgorithmIdAesCtr),
 126       blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageDecrypt);
 127
 128   std::vector<uint8_t> counter(16);
 129   std::vector<uint8_t> input(32);
 130   std::vector<uint8_t> output;
 131
 132   for (size_t i = 0; i < arraysize(kBadCounterLengthBits); ++i) {
 133     uint8_t bad_counter_length_bits = kBadCounterLengthBits[i];
 134
 135     EXPECT_EQ(Status::ErrorInvalidAesCtrCounterLength(),
 136               Encrypt(CreateAesCtrAlgorithm(counter, bad_counter_length_bits),
 137                       key, CryptoData(input), &output));
 138
 139     EXPECT_EQ(Status::ErrorInvalidAesCtrCounterLength(),
 140               Decrypt(CreateAesCtrAlgorithm(counter, bad_counter_length_bits),
 141                       key, CryptoData(input), &output));
 142   }
 143 }
 144
 145 // Tests wrap-around using a 4-bit counter.
 146 //
 147 // Wrap-around is allowed, however if the counter repeats itself an error should
 148 // be thrown.
 149 //
 150 // Using a 4-bit counter it is possible to encrypt 16 blocks. However the 17th
 151 // block would end up wrapping back to the starting value.
 152 TEST(WebCryptoAesCtrTest, OverflowAndRepeatCounter) {
 153   if (!SupportsAesCtr()) {
 154     LOG(WARNING) << "Skipping test because AES-CTR is not supported";
 155     return;
 156   }
 157
 158   const uint8_t kCounterLengthBits = 4;
 159   const uint8_t kStartCounter[] = {0, 1, 15};
 160
 161   blink::WebCryptoKey key = ImportSecretKeyFromRaw(
 162       std::vector<uint8>(16),  // 128-bit key of all zeros.
 163       CreateAlgorithm(blink::WebCryptoAlgorithmIdAesCtr),
 164       blink::WebCryptoKeyUsageEncrypt | blink::WebCryptoKeyUsageDecrypt);
 165
 166   std::vector<uint8_t> buffer(272);
 167
 168   // 16 and 17 AES blocks worth of data respectively (AES blocks are 16 bytes
 169   // long).
 170   CryptoData input_16(vector_as_array(&buffer), 256);
 171   CryptoData input_17(vector_as_array(&buffer), 272);
 172
 173   std::vector<uint8_t> output;
 174
 175   for (size_t i = 0; i < arraysize(kStartCounter); ++i) {
 176     std::vector<uint8_t> counter(16);
 177     counter[15] = kStartCounter[i];
 178
 179     // Baseline test: Encrypting 16 blocks should work (don't bother to check
 180     // output, the known answer tests already do that).
 181     EXPECT_EQ(Status::Success(),
 182               Encrypt(CreateAesCtrAlgorithm(counter, kCounterLengthBits), key,
 183                       input_16, &output));
 184
 185     // Encrypting/Decrypting 17 however should fail.
 186     EXPECT_EQ(Status::ErrorAesCtrInputTooLongCounterRepeated(),
 187               Encrypt(CreateAesCtrAlgorithm(counter, kCounterLengthBits), key,
 188                       input_17, &output));
 189     EXPECT_EQ(Status::ErrorAesCtrInputTooLongCounterRepeated(),
 190               Decrypt(CreateAesCtrAlgorithm(counter, kCounterLengthBits), key,
 191                       input_17, &output));
 192   }
 193 }
 194
 195 }  // namespace
 196
 197 }  // namespace webcrypto
 198
 199 }  // namespace content