Abseil Common Libraries (C++) (grcp 依赖)
https://abseil.io/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
102 lines
3.2 KiB
102 lines
3.2 KiB
// 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. |
|
|
|
#ifndef ABSL_RANDOM_INTERNAL_RANDEN_H_ |
|
#define ABSL_RANDOM_INTERNAL_RANDEN_H_ |
|
|
|
#include <cstddef> |
|
|
|
#include "absl/random/internal/platform.h" |
|
#include "absl/random/internal/randen_hwaes.h" |
|
#include "absl/random/internal/randen_slow.h" |
|
#include "absl/random/internal/randen_traits.h" |
|
|
|
namespace absl { |
|
ABSL_NAMESPACE_BEGIN |
|
namespace random_internal { |
|
|
|
// RANDen = RANDom generator or beetroots in Swiss High German. |
|
// 'Strong' (well-distributed, unpredictable, backtracking-resistant) random |
|
// generator, faster in some benchmarks than std::mt19937_64 and pcg64_c32. |
|
// |
|
// Randen implements the basic state manipulation methods. |
|
class Randen { |
|
public: |
|
static constexpr size_t kStateBytes = RandenTraits::kStateBytes; |
|
static constexpr size_t kCapacityBytes = RandenTraits::kCapacityBytes; |
|
static constexpr size_t kSeedBytes = RandenTraits::kSeedBytes; |
|
|
|
~Randen() = default; |
|
|
|
Randen(); |
|
|
|
// Generate updates the randen sponge. The outer portion of the sponge |
|
// (kCapacityBytes .. kStateBytes) may be consumed as PRNG state. |
|
template <typename T, size_t N> |
|
void Generate(T (&state)[N]) const { |
|
static_assert(N * sizeof(T) == kStateBytes, |
|
"Randen::Generate() requires kStateBytes of state"); |
|
#if ABSL_RANDOM_INTERNAL_AES_DISPATCH |
|
// HW AES Dispatch. |
|
if (has_crypto_) { |
|
RandenHwAes::Generate(keys_, state); |
|
} else { |
|
RandenSlow::Generate(keys_, state); |
|
} |
|
#elif ABSL_HAVE_ACCELERATED_AES |
|
// HW AES is enabled. |
|
RandenHwAes::Generate(keys_, state); |
|
#else |
|
// HW AES is disabled. |
|
RandenSlow::Generate(keys_, state); |
|
#endif |
|
} |
|
|
|
// Absorb incorporates additional seed material into the randen sponge. After |
|
// absorb returns, Generate must be called before the state may be consumed. |
|
template <typename S, size_t M, typename T, size_t N> |
|
void Absorb(const S (&seed)[M], T (&state)[N]) const { |
|
static_assert(M * sizeof(S) == RandenTraits::kSeedBytes, |
|
"Randen::Absorb() requires kSeedBytes of seed"); |
|
|
|
static_assert(N * sizeof(T) == RandenTraits::kStateBytes, |
|
"Randen::Absorb() requires kStateBytes of state"); |
|
#if ABSL_RANDOM_INTERNAL_AES_DISPATCH |
|
// HW AES Dispatch. |
|
if (has_crypto_) { |
|
RandenHwAes::Absorb(seed, state); |
|
} else { |
|
RandenSlow::Absorb(seed, state); |
|
} |
|
#elif ABSL_HAVE_ACCELERATED_AES |
|
// HW AES is enabled. |
|
RandenHwAes::Absorb(seed, state); |
|
#else |
|
// HW AES is disabled. |
|
RandenSlow::Absorb(seed, state); |
|
#endif |
|
} |
|
|
|
private: |
|
const void* keys_; |
|
#if ABSL_RANDOM_INTERNAL_AES_DISPATCH |
|
bool has_crypto_; |
|
#endif |
|
}; |
|
|
|
} // namespace random_internal |
|
ABSL_NAMESPACE_END |
|
} // namespace absl |
|
|
|
#endif // ABSL_RANDOM_INTERNAL_RANDEN_H_
|
|
|