tor-browser

salted_seed_seq_test.cc (5240B)

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// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "absl/random/internal/salted_seed_seq.h"

#include <iterator>
#include <random>
#include <utility>
#include <vector>

#include "gmock/gmock.h"
#include "gtest/gtest.h"

using absl::random_internal::GetSaltMaterial;
using absl::random_internal::MakeSaltedSeedSeq;
using absl::random_internal::SaltedSeedSeq;
using testing::Eq;
using testing::Pointwise;

namespace {

template <typename Sseq>
void ConformsToInterface() {
 // Check that the SeedSequence can be default-constructed.
 {
   Sseq default_constructed_seq;
 }
 // Check that the SeedSequence can be constructed with two iterators.
 {
   uint32_t init_array[] = {1, 3, 5, 7, 9};
   Sseq iterator_constructed_seq(std::begin(init_array), std::end(init_array));
 }
 // Check that the SeedSequence can be std::initializer_list-constructed.
 {
   Sseq list_constructed_seq = {1, 3, 5, 7, 9, 11, 13};
 }
 // Check that param() and size() return state provided to constructor.
 {
   uint32_t init_array[] = {1, 2, 3, 4, 5};
   Sseq seq(std::begin(init_array), std::end(init_array));
   EXPECT_EQ(seq.size(), ABSL_ARRAYSIZE(init_array));

   std::vector<uint32_t> state_vector;
   seq.param(std::back_inserter(state_vector));

   EXPECT_EQ(state_vector.size(), ABSL_ARRAYSIZE(init_array));
   for (int i = 0; i < state_vector.size(); i++) {
     EXPECT_EQ(state_vector[i], i + 1);
   }
 }
 // Check for presence of generate() method.
 {
   Sseq seq;
   uint32_t seeds[5];

   seq.generate(std::begin(seeds), std::end(seeds));
 }
}

TEST(SaltedSeedSeq, CheckInterfaces) {
 // Control case
 ConformsToInterface<std::seed_seq>();

 // Abseil classes
 ConformsToInterface<SaltedSeedSeq<std::seed_seq>>();
}

TEST(SaltedSeedSeq, CheckConstructingFromOtherSequence) {
 std::vector<uint32_t> seed_values(10, 1);
 std::seed_seq seq(seed_values.begin(), seed_values.end());
 auto salted_seq = MakeSaltedSeedSeq(std::move(seq));

 EXPECT_EQ(seq.size(), salted_seq.size());

 std::vector<uint32_t> param_result;
 seq.param(std::back_inserter(param_result));

 EXPECT_EQ(seed_values, param_result);
}

TEST(SaltedSeedSeq, SaltedSaltedSeedSeqIsNotDoubleSalted) {
 uint32_t init[] = {1, 3, 5, 7, 9};

 std::seed_seq seq(std::begin(init), std::end(init));

 // The first salting.
 SaltedSeedSeq<std::seed_seq> salted_seq = MakeSaltedSeedSeq(std::move(seq));
 uint32_t a[16];
 salted_seq.generate(std::begin(a), std::end(a));

 // The second salting.
 SaltedSeedSeq<std::seed_seq> salted_salted_seq =
     MakeSaltedSeedSeq(std::move(salted_seq));
 uint32_t b[16];
 salted_salted_seq.generate(std::begin(b), std::end(b));

 // ... both should be equal.
 EXPECT_THAT(b, Pointwise(Eq(), a)) << "a[0] " << a[0];
}

TEST(SaltedSeedSeq, SeedMaterialIsSalted) {
 const size_t kNumBlocks = 16;

 uint32_t seed_material[kNumBlocks];
 std::random_device urandom{"/dev/urandom"};
 for (uint32_t& seed : seed_material) {
   seed = urandom();
 }

 std::seed_seq seq(std::begin(seed_material), std::end(seed_material));
 SaltedSeedSeq<std::seed_seq> salted_seq(std::begin(seed_material),
                                         std::end(seed_material));

 bool salt_is_available = GetSaltMaterial().has_value();

 // If salt is available generated sequence should be different.
 if (salt_is_available) {
   uint32_t outputs[kNumBlocks];
   uint32_t salted_outputs[kNumBlocks];

   seq.generate(std::begin(outputs), std::end(outputs));
   salted_seq.generate(std::begin(salted_outputs), std::end(salted_outputs));

   EXPECT_THAT(outputs, Pointwise(testing::Ne(), salted_outputs));
 }
}

TEST(SaltedSeedSeq, GenerateAcceptsDifferentTypes) {
 const size_t kNumBlocks = 4;

 SaltedSeedSeq<std::seed_seq> seq({1, 2, 3});

 uint32_t expected[kNumBlocks];
 seq.generate(std::begin(expected), std::end(expected));

 // 32-bit outputs
 {
   unsigned long seed_material[kNumBlocks];  // NOLINT(runtime/int)
   seq.generate(std::begin(seed_material), std::end(seed_material));
   EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
 }
 {
   unsigned int seed_material[kNumBlocks];  // NOLINT(runtime/int)
   seq.generate(std::begin(seed_material), std::end(seed_material));
   EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
 }

 // 64-bit outputs.
 {
   uint64_t seed_material[kNumBlocks];
   seq.generate(std::begin(seed_material), std::end(seed_material));
   EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
 }
 {
   int64_t seed_material[kNumBlocks];
   seq.generate(std::begin(seed_material), std::end(seed_material));
   EXPECT_THAT(seed_material, Pointwise(Eq(), expected));
 }
}

}  // namespace