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

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1// Copyright (c) 2020-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 <chainparams.h>
6#include <consensus/amount.h>
7#include <consensus/merkle.h>
8#include <kernel/coinstats.h>
9#include <node/miner.h>
10#include <primitives/block.h>
11#include <primitives/transaction.h>
12#include <script/script.h>
13#include <sync.h>
14#include <test/fuzz/FuzzedDataProvider.h>
15#include <test/fuzz/fuzz.h>
16#include <test/fuzz/util.h>
17#include <test/util/mining.h>
18#include <test/util/random.h>
19#include <test/util/setup_common.h>
20#include <test/util/time.h>
21#include <txdb.h>
22#include <uint256.h>
23#include <util/check.h>
24#include <validation.h>
25
26#include <cstddef>
27#include <cstdint>
28#include <functional>
29#include <memory>
30#include <optional>
31#include <utility>
32#include <vector>
33
34FUZZ_TARGET(utxo_total_supply)
35{
36    SeedRandomStateForTest(SeedRand::ZEROS);
37    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
38    FakeNodeClock clock{ConsumeTime(fuzzed_data_provider, /*min=*/1296688602)}; // regtest genesis block timestamp
39    /** The testing setup that creates a chainman only (no chainstate) */
40    ChainTestingSetup test_setup{
41        ChainType::REGTEST,
42        {
43            .extra_args = {
44                "-testactivationheight=bip34@2",
45            },
46        },
47    };
48    // Create chainstate
49    test_setup.LoadVerifyActivateChainstate();
50    auto& node{test_setup.m_node};
51    auto& chainman{*Assert(test_setup.m_node.chainman)};
52
53    const auto ActiveHeight = [&]() {
54        LOCK(chainman.GetMutex());
55        return chainman.ActiveHeight();
56    };
57    const auto PrepareNextBlock = [&]() {
58        // Use OP_FALSE to avoid BIP30 check from hitting early
59        auto block = PrepareBlock(node, {
60            .coinbase_output_script = CScript() << OP_FALSE,
61        });
62        // Replace OP_FALSE with OP_TRUE
63        {
64            CMutableTransaction tx{*block->vtx.back()};
65            tx.nLockTime = 0; // Use the same nLockTime for all as we want to duplicate one of them.
66            tx.vout.at(0).scriptPubKey = CScript{} << OP_TRUE;
67            block->vtx.back() = MakeTransactionRef(tx);
68        }
69        return block;
70    };
71
72    /** The block template this fuzzer is working on */
73    auto current_block = PrepareNextBlock();
74    /** Append-only set of tx outpoints, entries are not removed when spent */
75    std::vector<std::pair<COutPoint, CTxOut>> txos;
76    /** The utxo stats at the chain tip */
77    kernel::CCoinsStats utxo_stats;
78    /** The total amount of coins in the utxo set */
79    CAmount circulation{0};
80
81
82    // Store the tx out in the txo map
83    const auto StoreLastTxo = [&]() {
84        // get last tx
85        const CTransaction& tx = *current_block->vtx.back();
86        // get last out
87        const uint32_t i = tx.vout.size() - 1;
88        // store it
89        txos.emplace_back(COutPoint{tx.GetHash(), i}, tx.vout.at(i));
90        if (current_block->vtx.size() == 1 && tx.vout.at(i).scriptPubKey[0] == OP_RETURN) {
91            // also store coinbase
92            const uint32_t i = tx.vout.size() - 2;
93            txos.emplace_back(COutPoint{tx.GetHash(), i}, tx.vout.at(i));
94        }
95    };
96    const auto AppendRandomTxo = [&](CMutableTransaction& tx) {
97        const auto& txo = txos.at(fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, txos.size() - 1));
98        tx.vin.emplace_back(txo.first);
99        tx.vout.emplace_back(txo.second.nValue, txo.second.scriptPubKey); // "Forward" coin with no fee
100    };
101    const auto UpdateUtxoStats = [&](bool wipe_cache) {
102        LOCK(chainman.GetMutex());
103        chainman.ActiveChainstate().ForceFlushStateToDisk(wipe_cache);
104        utxo_stats = std::move(
105            *Assert(kernel::ComputeUTXOStats(kernel::CoinStatsHashType::NONE, chainman.ActiveChainstate().CoinsDB(), chainman.m_blockman, {})));
106        // Check that miner can't print more money than they are allowed to
107        assert(circulation == utxo_stats.total_amount);
108    };
109
110
111    // Update internal state to chain tip
112    StoreLastTxo();
113    UpdateUtxoStats(/*wipe_cache=*/fuzzed_data_provider.ConsumeBool());
114    assert(ActiveHeight() == 0);
115    // Get at which height we duplicate the coinbase
116    // Assuming that the fuzzer will mine relatively short chains (less than 200 blocks), we want the duplicate coinbase to be not too high.
117    // Up to 300 seems reasonable.
118    int64_t duplicate_coinbase_height = fuzzed_data_provider.ConsumeIntegralInRange(0, 300);
119    // Avoid bad-cb-length error at heights <= 16. Pad the BIP34-encoded height
120    // with OP_0 to satisfy the minimum 2-byte coinbase scriptSig length.
121    CScript duplicate_coinbase_script = CScript() << duplicate_coinbase_height;
122    if (duplicate_coinbase_height <= 16) {
123        duplicate_coinbase_script << OP_0;
124    }
125    // Mine the first block with this duplicate
126    current_block = PrepareNextBlock();
127    StoreLastTxo();
128
129    {
130        // Create duplicate (CScript should match exact format as in CreateNewBlock)
131        CMutableTransaction tx{*current_block->vtx.front()};
132        tx.vin.at(0).scriptSig = duplicate_coinbase_script;
133
134        // Mine block and create next block template
135        current_block->vtx.front() = MakeTransactionRef(tx);
136    }
137    current_block->hashMerkleRoot = BlockMerkleRoot(*current_block);
138    assert(!MineBlock(node, current_block).IsNull());
139    circulation += GetBlockSubsidy(ActiveHeight(), Params().GetConsensus());
140
141    assert(ActiveHeight() == 1);
142    UpdateUtxoStats(/*wipe_cache=*/fuzzed_data_provider.ConsumeBool());
143    current_block = PrepareNextBlock();
144    StoreLastTxo();
145
146    // Limit to avoid timeout, but enough to cover duplicate_coinbase_height
147    // and CVE-2018-17144.
148    LIMITED_WHILE (fuzzed_data_provider.remaining_bytes(), 2'00) {
149        CallOneOf(
150            fuzzed_data_provider,
151            [&] {
152                // Append an input-output pair to the last tx in the current block
153                CMutableTransaction tx{*current_block->vtx.back()};
154                AppendRandomTxo(tx);
155                current_block->vtx.back() = MakeTransactionRef(tx);
156                StoreLastTxo();
157            },
158            [&] {
159                // Append a tx to the list of txs in the current block
160                CMutableTransaction tx{};
161                AppendRandomTxo(tx);
162                current_block->vtx.push_back(MakeTransactionRef(tx));
163                StoreLastTxo();
164            },
165            [&] {
166                // Append the current block to the active chain
167                node::RegenerateCommitments(*current_block, chainman);
168                const bool was_valid = !MineBlock(node, current_block).IsNull();
169
170                const uint256 prev_hash_serialized{utxo_stats.hashSerialized};
171                if (was_valid) {
172                    if (duplicate_coinbase_height == ActiveHeight()) {
173                        // we mined the duplicate coinbase
174                        assert(current_block->vtx.at(0)->vin.at(0).scriptSig == duplicate_coinbase_script);
175                    }
176
177                    circulation += GetBlockSubsidy(ActiveHeight(), Params().GetConsensus());
178                }
179
180                UpdateUtxoStats(/*wipe_cache=*/fuzzed_data_provider.ConsumeBool());
181
182                if (!was_valid) {
183                    // utxo stats must not change
184                    assert(prev_hash_serialized == utxo_stats.hashSerialized);
185                }
186
187                current_block = PrepareNextBlock();
188                StoreLastTxo();
189            });
190    }
191}
192

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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