blob: 12eeac203786573633ab5965e802de85c04372e6 [file] [log] [blame]
#include "quiche/common/quiche_random.h"
#include <cstdint>
#include <cstring>
#include "openssl/rand.h"
#include "quiche/common/platform/api/quiche_logging.h"
namespace quiche {
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 Xoshiro256InitializeRngStateMember() {
uint64_t result;
RAND_bytes(reinterpret_cast<uint8_t*>(&result), sizeof(result));
return result;
}
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] = {
Xoshiro256InitializeRngStateMember(),
Xoshiro256InitializeRngStateMember(),
Xoshiro256InitializeRngStateMember(),
Xoshiro256InitializeRngStateMember()};
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 DefaultQuicheRandom : public QuicheRandom {
public:
DefaultQuicheRandom() {}
DefaultQuicheRandom(const DefaultQuicheRandom&) = delete;
DefaultQuicheRandom& operator=(const DefaultQuicheRandom&) = delete;
~DefaultQuicheRandom() 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 DefaultQuicheRandom::RandBytes(void* data, size_t len) {
RAND_bytes(reinterpret_cast<uint8_t*>(data), len);
}
uint64_t DefaultQuicheRandom::RandUint64() {
uint64_t value;
RandBytes(&value, sizeof(value));
return value;
}
void DefaultQuicheRandom::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 DefaultQuicheRandom::InsecureRandUint64() {
return Xoshiro256PlusPlus();
}
} // namespace
// static
QuicheRandom* QuicheRandom::GetInstance() {
static DefaultQuicheRandom* random = new DefaultQuicheRandom();
return random;
}
} // namespace quiche