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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

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1// Copyright (c) 2024-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#include <arith_uint256.h>
6#include <policy/feerate.h>
7#include <util/feefrac.h>
8#include <test/fuzz/FuzzedDataProvider.h>
9#include <test/fuzz/fuzz.h>
10#include <test/fuzz/util.h>
11
12#include <compare>
13#include <cmath>
14#include <cstdint>
15#include <iostream>
16
17namespace {
18
19/** The maximum absolute value of an int64_t, as an arith_uint256 (2^63). */
20const auto MAX_ABS_INT64 = arith_uint256{1} << 63;
21
22/** Construct an arith_uint256 whose value equals abs(x). */
23arith_uint256 Abs256(int64_t x)
24{
25    if (x >= 0) {
26        // For positive numbers, pass through the value.
27        return arith_uint256{static_cast<uint64_t>(x)};
28    } else if (x > std::numeric_limits<int64_t>::min()) {
29        // For negative numbers, negate first.
30        return arith_uint256{static_cast<uint64_t>(-x)};
31    } else {
32        // Special case for x == -2^63 (for which -x results in integer overflow).
33        return MAX_ABS_INT64;
34    }
35}
36
37/** Construct an arith_uint256 whose value equals abs(x), for 96-bit x. */
38arith_uint256 Abs256(std::pair<int64_t, uint32_t> x)
39{
40    if (x.first >= 0) {
41        // x.first and x.second are both non-negative; sum their absolute values.
42        return (Abs256(x.first) << 32) + Abs256(x.second);
43    } else {
44        // x.first is negative and x.second is non-negative; subtract the absolute values.
45        return (Abs256(x.first) << 32) - Abs256(x.second);
46    }
47}
48
49std::strong_ordering MulCompare(int64_t a1, int64_t a2, int64_t b1, int64_t b2)
50{
51    // Compute and compare signs.
52    int sign_a = (a1 == 0 ? 0 : a1 < 0 ? -1 : 1) * (a2 == 0 ? 0 : a2 < 0 ? -1 : 1);
53    int sign_b = (b1 == 0 ? 0 : b1 < 0 ? -1 : 1) * (b2 == 0 ? 0 : b2 < 0 ? -1 : 1);
54    if (sign_a != sign_b) return sign_a <=> sign_b;
55
56    // Compute absolute values of products.
57    auto mul_abs_a = Abs256(a1) * Abs256(a2), mul_abs_b = Abs256(b1) * Abs256(b2);
58
59    // Compute products of absolute values.
60    if (sign_a < 0) {
61        return mul_abs_b <=> mul_abs_a;
62    } else {
63        return mul_abs_a <=> mul_abs_b;
64    }
65}
66
67} // namespace
68
69FUZZ_TARGET(feefrac)
70{
71    FuzzedDataProvider provider(buffer.data(), buffer.size());
72
73    int64_t f1 = provider.ConsumeIntegral<int64_t>();
74    int32_t s1 = provider.ConsumeIntegral<int32_t>();
75    if (s1 == 0) f1 = 0;
76    FeeFrac fr1(f1, s1);
77    assert(fr1.IsEmpty() == (s1 == 0));
78
79    int64_t f2 = provider.ConsumeIntegral<int64_t>();
80    int32_t s2 = provider.ConsumeIntegral<int32_t>();
81    if (s2 == 0) f2 = 0;
82    FeeFrac fr2(f2, s2);
83    assert(fr2.IsEmpty() == (s2 == 0));
84
85    // Feerate comparisons
86    auto cmp_feerate = MulCompare(f1, s2, f2, s1);
87    assert((ByRatio{fr1} <=> ByRatio{fr2}) == cmp_feerate);
88    assert((ByRatio{fr1} < ByRatio{fr2}) == std::is_lt(cmp_feerate));
89    assert((ByRatio{fr1} > ByRatio{fr2}) == std::is_gt(cmp_feerate));
90
91    // Compare with manual invocation of FeeFrac::Mul.
92    auto cmp_mul = FeeFrac::Mul(f1, s2) <=> FeeFrac::Mul(f2, s1);
93    assert(cmp_mul == cmp_feerate);
94
95    // Same, but using FeeFrac::MulFallback.
96    auto cmp_fallback = FeeFrac::MulFallback(f1, s2) <=> FeeFrac::MulFallback(f2, s1);
97    assert(cmp_fallback == cmp_feerate);
98
99    // Total order comparisons
100    auto cmp_total = std::is_eq(cmp_feerate) ? (s2 <=> s1) : cmp_feerate;
101    assert((ByRatioNegSize{fr1} <=> ByRatioNegSize{fr2}) == cmp_total);
102    assert((ByRatioNegSize{fr1} < ByRatioNegSize{fr2}) == std::is_lt(cmp_total));
103    assert((ByRatioNegSize{fr1} > ByRatioNegSize{fr2}) == std::is_gt(cmp_total));
104    assert((ByRatioNegSize{fr1} <= ByRatioNegSize{fr2}) == std::is_lteq(cmp_total));
105    assert((ByRatioNegSize{fr1} >= ByRatioNegSize{fr2}) == std::is_gteq(cmp_total));
106    assert((ByRatioNegSize{fr1} == ByRatioNegSize{fr2}) == std::is_eq(cmp_total));
107    assert((ByRatioNegSize{fr1} != ByRatioNegSize{fr2}) == std::is_neq(cmp_total));
108}
109
110FUZZ_TARGET(feefrac_div_fallback)
111{
112    // Verify the behavior of FeeFrac::DivFallback over all possible inputs.
113
114    // Construct a 96-bit signed value num, a positive 31-bit value den, and rounding mode.
115    FuzzedDataProvider provider(buffer.data(), buffer.size());
116    auto num_high = provider.ConsumeIntegral<int64_t>();
117    auto num_low = provider.ConsumeIntegral<uint32_t>();
118    std::pair<int64_t, uint32_t> num{num_high, num_low};
119    auto den = provider.ConsumeIntegralInRange<int32_t>(1, std::numeric_limits<int32_t>::max());
120    auto round_down = provider.ConsumeBool();
121
122    // Predict the sign of the actual result.
123    bool is_negative = num_high < 0;
124    // Evaluate absolute value using arith_uint256. If the actual result is negative and we are
125    // rounding down, or positive and we are rounding up, the absolute value of the quotient is
126    // the rounded-up quotient of the absolute values.
127    auto num_abs = Abs256(num);
128    auto den_abs = Abs256(den);
129    auto quot_abs = (is_negative == round_down) ?
130        (num_abs + den_abs - 1) / den_abs :
131        num_abs / den_abs;
132
133    // If the result is not representable by an int64_t, bail out.
134    if ((is_negative && quot_abs > MAX_ABS_INT64) || (!is_negative && quot_abs >= MAX_ABS_INT64)) {
135        return;
136    }
137
138    // Verify the behavior of FeeFrac::DivFallback.
139    auto res = FeeFrac::DivFallback(num, den, round_down);
140    assert(res == 0 || (res < 0) == is_negative);
141    assert(Abs256(res) == quot_abs);
142
143    // Compare approximately with floating-point.
144    long double expect = round_down ? std::floor(num_high * 4294967296.0L + num_low) / den
145                                    : std::ceil(num_high * 4294967296.0L + num_low) / den;
146    // Expect to be accurate within 50 bits of precision, +- 1 sat.
147    if (expect == 0.0L) {
148        assert(res >= -1 && res <= 1);
149    } else if (expect > 0.0L) {
150        assert(res >= expect * 0.999999999999999L - 1.0L);
151        assert(res <= expect * 1.000000000000001L + 1.0L);
152    } else {
153        assert(res >= expect * 1.000000000000001L - 1.0L);
154        assert(res <= expect * 0.999999999999999L + 1.0L);
155    }
156}
157
158FUZZ_TARGET(feefrac_mul_div)
159{
160    // Verify the behavior of:
161    // - The combination of FeeFrac::Mul + FeeFrac::Div.
162    // - The combination of FeeFrac::MulFallback + FeeFrac::DivFallback.
163    // - FeeFrac::Evaluate.
164
165    // Construct a 32-bit signed multiplicand, a 64-bit signed multiplicand, a positive 31-bit
166    // divisor, and a rounding mode.
167    FuzzedDataProvider provider(buffer.data(), buffer.size());
168    auto mul32 = provider.ConsumeIntegral<int32_t>();
169    auto mul64 = provider.ConsumeIntegral<int64_t>();
170    auto div = provider.ConsumeIntegralInRange<int32_t>(1, std::numeric_limits<int32_t>::max());
171    auto round_down = provider.ConsumeBool();
172
173    // Predict the sign of the overall result.
174    bool is_negative = ((mul32 < 0) && (mul64 > 0)) || ((mul32 > 0) && (mul64 < 0));
175    // Evaluate absolute value using arith_uint256. If the actual result is negative and we are
176    // rounding down or positive and we rounding up, the absolute value of the quotient is the
177    // rounded-up quotient of the absolute values.
178    auto prod_abs = Abs256(mul32) * Abs256(mul64);
179    auto div_abs = Abs256(div);
180    auto quot_abs = (is_negative == round_down) ?
181        (prod_abs + div_abs - 1) / div_abs :
182        prod_abs / div_abs;
183
184    // If the result is not representable by an int64_t, bail out.
185    if ((is_negative && quot_abs > MAX_ABS_INT64) || (!is_negative && quot_abs >= MAX_ABS_INT64)) {
186        // If 0 <= mul32 <= div, then the result is guaranteed to be representable. In the context
187        // of the Evaluate{Down,Up} calls below, this corresponds to 0 <= at_size <= feefrac.size.
188        assert(mul32 < 0 || mul32 > div);
189        return;
190    }
191
192    // Verify the behavior of FeeFrac::Mul + FeeFrac::Div.
193    auto res = FeeFrac::Div(FeeFrac::Mul(mul64, mul32), div, round_down);
194    assert(res == 0 || (res < 0) == is_negative);
195    assert(Abs256(res) == quot_abs);
196
197    // Verify the behavior of FeeFrac::MulFallback + FeeFrac::DivFallback.
198    auto res_fallback = FeeFrac::DivFallback(FeeFrac::MulFallback(mul64, mul32), div, round_down);
199    assert(res == res_fallback);
200
201    // Compare approximately with floating-point.
202    long double expect = round_down ? std::floor(static_cast<long double>(mul32) * mul64 / div)
203                                    : std::ceil(static_cast<long double>(mul32) * mul64 / div);
204    // Expect to be accurate within 50 bits of precision, +- 1 sat.
205    if (expect == 0.0L) {
206        assert(res >= -1 && res <= 1);
207    } else if (expect > 0.0L) {
208        assert(res >= expect * 0.999999999999999L - 1.0L);
209        assert(res <= expect * 1.000000000000001L + 1.0L);
210    } else {
211        assert(res >= expect * 1.000000000000001L - 1.0L);
212        assert(res <= expect * 0.999999999999999L + 1.0L);
213    }
214
215    // Verify the behavior of FeeFrac::Evaluate{Down,Up}.
216    if (mul32 >= 0) {
217        auto res_fee = round_down ?
218            FeeFrac{mul64, div}.EvaluateFeeDown(mul32) :
219            FeeFrac{mul64, div}.EvaluateFeeUp(mul32);
220        assert(res == res_fee);
221
222        // Compare approximately with CFeeRate.
223        if (mul64 < std::numeric_limits<int64_t>::max() / 1000 &&
224            mul64 > std::numeric_limits<int64_t>::min() / 1000 &&
225            quot_abs < arith_uint256{std::numeric_limits<int64_t>::max() / 1000}) {
226            CFeeRate feerate(mul64, div);
227            CAmount feerate_fee{feerate.GetFee(mul32)};
228            auto allowed_gap = static_cast<int64_t>(mul32 / 1000 + 3 + round_down);
229            assert(feerate_fee - res_fee >= -allowed_gap);
230            assert(feerate_fee - res_fee <= allowed_gap);
231        }
232    }
233}
234

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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