phantom/bitcoin
1
0
Fork 0
mirror of https://github.com/bitcoin/bitcoin.git synced 2025-01-09 11:27:28 -03:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

fuzz: Abort when global PRNG is used before SeedRand::ZEROS

Browse source
This commit is contained in:
MarcoFalke 2024-12-20 16:15:32 +01:00
parent 433412fd84
commit fa3c787b62
No known key found for this signature in database
3 changed files with 10 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
src/test/fuzz/fuzz.cpp
View file

@ -79,7 +79,7 @@ void FuzzFrameworkRegisterTarget(std::string_view name, TypeTestOneInput target,
static std::string_view g_fuzz_target;
static const TypeTestOneInput* g_test_one_input{nullptr};
inline void test_one_input(FuzzBufferType buffer)
static void test_one_input(FuzzBufferType buffer)
{
CheckGlobals check{};
(*Assert(g_test_one_input))(buffer);
@ -108,12 +108,12 @@ void ResetCoverageCounters() {}
#endif
void initialize()
static void initialize()
{
// By default, make the RNG deterministic with a fixed seed. This will affect all
// randomness during the fuzz test, except:
// - GetStrongRandBytes(), which is used for the creation of private key material.
// - Creating a BasicTestingSetup or derived class will switch to a random seed.
// - Randomness obtained before this call in g_rng_temp_path_init
SeedRandomStateForTest(SeedRand::ZEROS);
// Terminate immediately if a fuzzing harness ever tries to create a socket.

8
src/test/util/random.cpp
View file

@ -1,4 +1,4 @@
// Copyright (c) 2023 The Bitcoin Core developers
// Copyright (c) 2023-present The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
@ -24,7 +24,8 @@ void SeedRandomStateForTest(SeedRand seedtype)
// MakeRandDeterministicDANGEROUS is called, the output of GetRandHash is
// no longer truly random. It should be enough to get the seed once for the
// process.
static const uint256 ctx_seed = []() {
static const auto g_ctx_seed = []() -> std::optional<uint256> {
if constexpr (G_FUZZING) return {};
// If RANDOM_CTX_SEED is set, use that as seed.
if (const char* num{std::getenv(RANDOM_CTX_SEED)}) {
if (auto num_parsed{uint256::FromUserHex(num)}) {
@ -41,8 +42,9 @@ void SeedRandomStateForTest(SeedRand seedtype)
g_seeded_g_prng_zero = seedtype == SeedRand::ZEROS;
if constexpr (G_FUZZING) {
Assert(g_seeded_g_prng_zero); // Only SeedRandomStateForTest(SeedRand::ZEROS) is allowed in fuzz tests
Assert(!g_used_g_prng); // The global PRNG must not have been used before SeedRandomStateForTest(SeedRand::ZEROS)
}
const uint256& seed{seedtype == SeedRand::FIXED_SEED ? ctx_seed : uint256::ZERO};
const uint256& seed{seedtype == SeedRand::FIXED_SEED ? g_ctx_seed.value() : uint256::ZERO};
LogInfo("Setting random seed for current tests to %s=%s\n", RANDOM_CTX_SEED, seed.GetHex());
MakeRandDeterministicDANGEROUS(seed);
}

2
src/test/util/setup_common.cpp
View file

@ -79,7 +79,9 @@ constexpr inline auto TEST_DIR_PATH_ELEMENT{"test_common bitcoin"}; // Includes
static FastRandomContext g_rng_temp_path;
static const bool g_rng_temp_path_init{[] {
// Must be initialized before any SeedRandomForTest
Assert(!g_used_g_prng);
(void)g_rng_temp_path.rand64();
g_used_g_prng = false;
return true;
}()};