Files
nearby/internal/crypto/random_unittest.cc
T
Janusz Sobczak 0cb5b004e4 Add more Rand helper methods
PiperOrigin-RevId: 491409479
2022-11-28 12:14:19 -08:00

67 lines
1.8 KiB
C++

// Copyright 2020 Google LLC
//
// 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 "internal/crypto/random.h"
#include <stddef.h>
#include <string>
#include "gtest/gtest.h"
#include "internal/crypto/nearby_base.h"
// Basic functionality tests. Does NOT test the security of the random data.
namespace crypto {
namespace {
// Ensures we don't have all trivial data, i.e. that the data is indeed random.
// Currently, that means the bytes cannot be all the same (e.g. all zeros).
bool IsTrivial(const std::string& bytes) {
for (size_t i = 0; i < bytes.size(); i++) {
if (bytes[i] != bytes[0]) {
return false;
}
}
return true;
}
TEST(RandBytes, RandBytes) {
std::string bytes(16, '\0');
RandBytes(nearbybase::WriteInto(&bytes, bytes.size()), bytes.size());
EXPECT_TRUE(!IsTrivial(bytes));
}
TEST(RandBytes, RandomString) {
constexpr size_t kSize = 30;
std::string bytes = RandBytes(kSize);
EXPECT_EQ(bytes.size(), kSize);
EXPECT_TRUE(!IsTrivial(bytes));
}
TEST(RandBytes, RandData) {
uint64_t x = RandData<uint64_t>();
uint64_t y = RandData<uint64_t>();
// Once in a billion years, consecutively generated random numbers will be
// the same and the test will fail.
EXPECT_NE(x, y);
EXPECT_NE(x >> 32, x & 0xFFFFFFFF);
}
} // namespace
} // namespace crypto