components/rappor/byte_vector_utils_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 "components/rappor/byte_vector_utils.h"
   6
   7 #include "base/rand_util.h"
   8 #include "base/strings/string_number_conversions.h"
   9 #include "testing/gtest/include/gtest/gtest.h"
  10
  11 namespace rappor {
  12
  13 namespace {
  14
  15 class SecondRequest : public HmacByteVectorGenerator {
  16  public:
  17   SecondRequest(const HmacByteVectorGenerator& first_request)
  18       : HmacByteVectorGenerator(first_request) {}
  19 };
  20
  21 std::string HexToString(const char* hex) {
  22   ByteVector bv;
  23   base::HexStringToBytes(hex, &bv);
  24   return std::string(bv.begin(), bv.end());
  25 }
  26
  27 }  // namespace
  28
  29 TEST(ByteVectorTest, Uint64ToByteVectorSmall) {
  30   ByteVector bytes(1);
  31   Uint64ToByteVector(0x10, 1, &bytes);
  32   EXPECT_EQ(1u, bytes.size());
  33   EXPECT_EQ(0x10, bytes[0]);
  34 }
  35
  36 TEST(ByteVectorTest, Uint64ToByteVectorLarge) {
  37   ByteVector bytes(8);
  38   Uint64ToByteVector(0xfedcba9876543210, 8, &bytes);
  39   EXPECT_EQ(8u, bytes.size());
  40   EXPECT_EQ(0x10, bytes[0]);
  41   EXPECT_EQ(0xfe, bytes[7]);
  42 }
  43
  44 TEST(ByteVectorTest, ByteVectorAnd) {
  45   ByteVector lhs(2);
  46   lhs[1] = 0x12;
  47   ByteVector rhs(2);
  48   rhs[1] = 0x03;
  49
  50   EXPECT_EQ(0x02, (*ByteVectorAnd(lhs, &rhs))[1]);
  51 }
  52
  53 TEST(ByteVectorTest, ByteVectorOr) {
  54   ByteVector lhs(2);
  55   lhs[1] = 0x12;
  56   ByteVector rhs(2);
  57   rhs[1] = 0x03;
  58
  59   EXPECT_EQ(0x13, (*ByteVectorOr(lhs, &rhs))[1]);
  60 }
  61
  62 TEST(ByteVectorTest, ByteVectorMerge) {
  63   ByteVector lhs(2);
  64   lhs[1] = 0x33;
  65   ByteVector rhs(2);
  66   rhs[1] = 0x55;
  67   ByteVector mask(2);
  68   mask[1] = 0x0f;
  69
  70   EXPECT_EQ(0x35, (*ByteVectorMerge(mask, lhs, &rhs))[1]);
  71 }
  72
  73 TEST(ByteVectorTest, ByteVectorGenerator) {
  74   ByteVectorGenerator generator(2u);
  75   ByteVector random_50 = generator.GetWeightedRandomByteVector(PROBABILITY_50);
  76   EXPECT_EQ(random_50.size(), 2u);
  77   ByteVector random_75 = generator.GetWeightedRandomByteVector(PROBABILITY_75);
  78   EXPECT_EQ(random_75.size(), 2u);
  79 }
  80
  81 TEST(ByteVectorTest, HmacByteVectorGenerator) {
  82   HmacByteVectorGenerator generator(1u,
  83       std::string(HmacByteVectorGenerator::kEntropyInputSize, 0x00), "");
  84   ByteVector random_50 = generator.GetWeightedRandomByteVector(PROBABILITY_50);
  85   EXPECT_EQ(random_50.size(), 1u);
  86   EXPECT_EQ(random_50[0], 0x0B);
  87   ByteVector random_75 = generator.GetWeightedRandomByteVector(PROBABILITY_75);
  88   EXPECT_EQ(random_75.size(), 1u);
  89   EXPECT_EQ(random_75[0], 0xdf);
  90 }
  91
  92 TEST(ByteVectorTest, HmacNist) {
  93   // Test case 0 for SHA-256 HMAC_DRBG no reseed tests from
  94   // http://csrc.nist.gov/groups/STM/cavp/
  95   const char entropy[] =
  96       "ca851911349384bffe89de1cbdc46e6831e44d34a4fb935ee285dd14b71a7488";
  97   const char nonce[] = "659ba96c601dc69fc902940805ec0ca8";
  98   const char expected[] =
  99       "e528e9abf2dece54d47c7e75e5fe302149f817ea9fb4bee6f4199697d04d5b89"
 100       "d54fbb978a15b5c443c9ec21036d2460b6f73ebad0dc2aba6e624abf07745bc1"
 101       "07694bb7547bb0995f70de25d6b29e2d3011bb19d27676c07162c8b5ccde0668"
 102       "961df86803482cb37ed6d5c0bb8d50cf1f50d476aa0458bdaba806f48be9dcb8";
 103
 104   std::string entropy_input = HexToString(entropy) + HexToString(nonce);
 105   HmacByteVectorGenerator generator(1024u / 8, entropy_input, "");
 106   generator.GetWeightedRandomByteVector(PROBABILITY_50);
 107   SecondRequest generator2(generator);
 108   ByteVector random_50 = generator2.GetWeightedRandomByteVector(PROBABILITY_50);
 109
 110   EXPECT_EQ(HexToString(expected),
 111       std::string(random_50.begin(), random_50.end()));
 112 }
 113
 114 TEST(ByteVectorTest, WeightedRandomStatistics50) {
 115   ByteVectorGenerator generator(50u);
 116   ByteVector random = generator.GetWeightedRandomByteVector(PROBABILITY_50);
 117   int bit_count = CountBits(random);
 118   // Check bounds on bit counts that are true with 99.999% probability.
 119   EXPECT_GT(bit_count, 155); // Binomial(400, .5) CDF(155) ~= 0.000004
 120   EXPECT_LE(bit_count, 244); // Binomial(400, .5) CDF(244) ~= 0.999996
 121 }
 122
 123 TEST(ByteVectorTest, WeightedRandomStatistics75) {
 124   ByteVectorGenerator generator(50u);
 125   ByteVector random = generator.GetWeightedRandomByteVector(PROBABILITY_75);
 126   int bit_count = CountBits(random);
 127   // Check bounds on bit counts that are true with 99.999% probability.
 128   EXPECT_GT(bit_count, 259); // Binomial(400, .75) CDF(259) ~= 0.000003
 129   EXPECT_LE(bit_count, 337); // Binomial(400, .75) CDF(337) ~= 0.999997
 130 }
 131
 132 TEST(ByteVectorTest, HmacWeightedRandomStatistics50) {
 133   HmacByteVectorGenerator generator(50u,
 134       HmacByteVectorGenerator::GenerateEntropyInput(), "");
 135   ByteVector random = generator.GetWeightedRandomByteVector(PROBABILITY_50);
 136   int bit_count = CountBits(random);
 137   // Check bounds on bit counts that are true with 99.999% probability.
 138   EXPECT_GT(bit_count, 155); // Binomial(400, .5) CDF(155) ~= 0.000004
 139   EXPECT_LE(bit_count, 244); // Binomial(400, .5) CDF(244) ~= 0.999996
 140 }
 141
 142 TEST(ByteVectorTest, HmacWeightedRandomStatistics75) {
 143   HmacByteVectorGenerator generator(50u,
 144       HmacByteVectorGenerator::GenerateEntropyInput(), "");
 145   ByteVector random = generator.GetWeightedRandomByteVector(PROBABILITY_75);
 146   int bit_count = CountBits(random);
 147   // Check bounds on bit counts that are true with 99.999% probability.
 148   EXPECT_GT(bit_count, 259); // Binomial(400, .75) CDF(259) ~= 0.000003
 149   EXPECT_LE(bit_count, 337); // Binomial(400, .75) CDF(337) ~= 0.999997
 150 }
 151
 152 }  // namespace rappor