blob: 56657b507f96272f4c4199e4c670960bc35dc8e3 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "quic/core/crypto/quic_random.h"
#include <cstdint>
#include <cstring>
#include "third_party/boringssl/src/include/openssl/rand.h"
#include "quic/platform/api/quic_bug_tracker.h"
#include "quic/platform/api/quic_logging.h"
#include "common/platform/api/quiche_logging.h"
namespace quic {
namespace {
// Insecure randomness in DefaultRandom uses an implementation of
// xoshiro256++ 1.0 based on code in the public domain from
// <http://prng.di.unimi.it/xoshiro256plusplus.c>.
inline uint64_t Xoshiro256PlusPlusRotLeft(uint64_t x, int k) {
return (x << k) | (x >> (64 - k));
}
uint64_t Xoshiro256PlusPlus() {
static thread_local uint64_t rng_state[4];
static thread_local bool rng_state_initialized = false;
if (QUIC_PREDICT_FALSE(!rng_state_initialized)) {
RAND_bytes(reinterpret_cast<uint8_t*>(&rng_state), sizeof(rng_state));
rng_state_initialized = true;
}
const uint64_t result =
Xoshiro256PlusPlusRotLeft(rng_state[0] + rng_state[3], 23) + rng_state[0];
const uint64_t t = rng_state[1] << 17;
rng_state[2] ^= rng_state[0];
rng_state[3] ^= rng_state[1];
rng_state[1] ^= rng_state[2];
rng_state[0] ^= rng_state[3];
rng_state[2] ^= t;
rng_state[3] = Xoshiro256PlusPlusRotLeft(rng_state[3], 45);
return result;
}
class DefaultRandom : public QuicRandom {
public:
DefaultRandom() {}
DefaultRandom(const DefaultRandom&) = delete;
DefaultRandom& operator=(const DefaultRandom&) = delete;
~DefaultRandom() override {}
// QuicRandom implementation
void RandBytes(void* data, size_t len) override;
uint64_t RandUint64() override;
void InsecureRandBytes(void* data, size_t len) override;
uint64_t InsecureRandUint64() override;
};
void DefaultRandom::RandBytes(void* data, size_t len) {
RAND_bytes(reinterpret_cast<uint8_t*>(data), len);
}
uint64_t DefaultRandom::RandUint64() {
uint64_t value;
RandBytes(&value, sizeof(value));
return value;
}
void DefaultRandom::InsecureRandBytes(void* data, size_t len) {
while (len >= sizeof(uint64_t)) {
uint64_t random_bytes64 = Xoshiro256PlusPlus();
memcpy(data, &random_bytes64, sizeof(uint64_t));
data = reinterpret_cast<char*>(data) + sizeof(uint64_t);
len -= sizeof(uint64_t);
}
if (len > 0) {
QUICHE_DCHECK_LT(len, sizeof(uint64_t));
uint64_t random_bytes64 = Xoshiro256PlusPlus();
memcpy(data, &random_bytes64, len);
}
}
uint64_t DefaultRandom::InsecureRandUint64() {
return Xoshiro256PlusPlus();
}
} // namespace
// static
QuicRandom* QuicRandom::GetInstance() {
static DefaultRandom* random = new DefaultRandom();
return random;
}
} // namespace quic