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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) 2023-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 <test/fuzz/util/descriptor.h>
6
7#include <key.h>
8#include <key_io.h>
9#include <pubkey.h>
10#include <span.h>
11#include <util/strencodings.h>
12
13#include <ranges>
14#include <stack>
15#include <vector>
16
17void MockedDescriptorConverter::Init()
18{
19    // The data to use as a private key or a seed for an xprv.
20    std::array<std::byte, 32> key_data{std::byte{1}};
21    // Generate keys of all kinds and store them in the keys array.
22    for (size_t i{0}; i < TOTAL_KEYS_GENERATED; i++) {
23        key_data[31] = std::byte(i);
24
25        // If this is a "raw" key, generate a normal privkey. Otherwise generate
26        // an extended one.
27        if (IdIsCompPubKey(i) || IdIsUnCompPubKey(i) || IdIsXOnlyPubKey(i) || IdIsConstPrivKey(i)) {
28            CKey privkey;
29            privkey.Set(key_data.begin(), key_data.end(), !IdIsUnCompPubKey(i));
30            if (IdIsCompPubKey(i) || IdIsUnCompPubKey(i)) {
31                CPubKey pubkey{privkey.GetPubKey()};
32                keys_str[i] = HexStr(pubkey);
33            } else if (IdIsXOnlyPubKey(i)) {
34                const XOnlyPubKey pubkey{privkey.GetPubKey()};
35                keys_str[i] = HexStr(pubkey);
36            } else {
37                keys_str[i] = EncodeSecret(privkey);
38            }
39        } else {
40            CExtKey ext_privkey;
41            ext_privkey.SetSeed(key_data);
42            if (IdIsXprv(i)) {
43                keys_str[i] = EncodeExtKey(ext_privkey);
44            } else {
45                const CExtPubKey ext_pubkey{ext_privkey.Neuter()};
46                keys_str[i] = EncodeExtPubKey(ext_pubkey);
47            }
48        }
49    }
50}
51
52std::optional<uint8_t> MockedDescriptorConverter::IdxFromHex(std::string_view hex_characters) const {
53    if (hex_characters.size() != 2) return {};
54    auto idx = ParseHex(hex_characters);
55    if (idx.size() != 1) return {};
56    return idx[0];
57}
58
59std::optional<std::string> MockedDescriptorConverter::GetDescriptor(std::string_view mocked_desc) const {
60    // The smallest fragment would be "pk(%00)"
61    if (mocked_desc.size() < 7) return {};
62
63    // The actual descriptor string to be returned.
64    std::string desc;
65    desc.reserve(mocked_desc.size());
66
67    // Replace all occurrences of '%' followed by two hex characters with the corresponding key.
68    for (size_t i = 0; i < mocked_desc.size();) {
69        if (mocked_desc[i] == '%') {
70            if (i + 3 >= mocked_desc.size()) return {};
71            if (const auto idx = IdxFromHex(mocked_desc.substr(i + 1, 2))) {
72                desc += keys_str[*idx];
73                i += 3;
74            } else {
75                return {};
76            }
77        } else {
78            desc += mocked_desc[i++];
79        }
80    }
81
82    return desc;
83}
84
85bool HasDeepDerivPath(std::span<const uint8_t> buff, const int max_depth)
86{
87    auto depth{0};
88    for (const auto& ch: buff) {
89        if (ch == ',') {
90            // A comma is always present between two key expressions, so we use that as a delimiter.
91            depth = 0;
92        } else if (ch == '/') {
93            if (++depth > max_depth) return true;
94        }
95    }
96    return false;
97}
98
99bool HasTooManySubFrag(std::span<const uint8_t> buff, const int max_subs, const size_t max_nested_subs)
100{
101    // We use a stack because there may be many nested sub-frags.
102    std::stack<int> counts;
103    for (const auto& ch: buff) {
104        // The fuzzer may generate an input with a ton of parentheses. Rule out pathological cases.
105        if (counts.size() > max_nested_subs) return true;
106
107        if (ch == '(') {
108            // A new fragment was opened, create a new sub-count for it and start as one since any fragment with
109            // parentheses has at least one sub.
110            counts.push(1);
111        } else if (ch == ',' && !counts.empty()) {
112            // When encountering a comma, account for an additional sub in the last opened fragment. If it exceeds the
113            // limit, bail.
114            if (++counts.top() > max_subs) return true;
115        } else if (ch == ')' && !counts.empty()) {
116            // Fragment closed! Drop its sub count and resume to counting the number of subs for its parent.
117            counts.pop();
118        }
119    }
120    return false;
121}
122
123bool HasTooManyWrappers(std::span<const uint8_t> buff, const int max_wrappers)
124{
125    // The number of nested wrappers. Nested wrappers are always characters which follow each other so we don't have to
126    // use a stack as we do above when counting the number of sub-fragments.
127    std::optional<int> count;
128
129    // We want to detect nested wrappers. A wrapper is a character prepended to a fragment, separated by a colon. There
130    // may be more than one wrapper, in which case the colon is not repeated. For instance `jjjjj:pk()`.  To count
131    // wrappers we iterate in reverse and use the colon to detect the end of a wrapper expression and count how many
132    // characters there are since the beginning of the expression. We stop counting when we encounter a character
133    // indicating the beginning of a new expression.
134    for (const auto ch: buff | std::views::reverse) {
135        // A colon, start counting.
136        if (ch == ':') {
137            // The colon itself is not a wrapper so we start at 0.
138            count = 0;
139        } else if (count) {
140            // If we are counting wrappers, stop when we crossed the beginning of the wrapper expression. Otherwise keep
141            // counting and bail if we reached the limit.
142            // A wrapper may only ever occur as the first sub of a descriptor/miniscript expression ('('), as the
143            // first Taproot leaf in a pair ('{') or as the nth sub in each case (',').
144            if (ch == ',' || ch == '(' || ch == '{') {
145                count.reset();
146            } else if (++*count > max_wrappers) {
147                return true;
148            }
149        }
150    }
151
152    return false;
153}
154
155bool HasTooLargeLeafSize(std::span<const uint8_t> buff, const uint32_t max_leaf_size)
156{
157    uint32_t leaf_len{0};
158    for (auto c : buff) {
159        if (c == '(' || c == ')' || c == ',' || c == '{' || c == '}') {
160            // Possibly start a fresh leaf, or a fresh function name (with
161            // wrappers), or terminate a prior leaf.
162            leaf_len = 0;
163        } else {
164            // Just treat everything else as a leaf. This will also reject long
165            // function names, but this should be fine if the max_leaf_size is
166            // set large enough.
167            if (++leaf_len > max_leaf_size) {
168                return true;
169            }
170        }
171    }
172    return false;
173}
174

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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