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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

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1// Copyright (c) 2009-2010 Satoshi Nakamoto
2// Copyright (c) 2009-present The Bitcoin Core developers
3// Distributed under the MIT software license, see the accompanying
4// file COPYING or http://www.opensource.org/licenses/mit-license.php.
5
6#ifndef BITCOIN_SCRIPT_SIGNINGPROVIDER_H
7#define BITCOIN_SCRIPT_SIGNINGPROVIDER_H
8
9#include <addresstype.h>
10#include <attributes.h>
11#include <key.h>
12#include <pubkey.h>
13#include <script/keyorigin.h>
14#include <script/script.h>
15#include <sync.h>
16#include <uint256.h>
17
18#include <compare>
19#include <cstdint>
20#include <functional>
21#include <map>
22#include <memory>
23#include <optional>
24#include <set>
25#include <span>
26#include <tuple>
27#include <utility>
28#include <vector>
29
30class MuSig2SecNonce;
31
32struct ShortestVectorFirstComparator
33{
34    bool operator()(const std::vector<unsigned char>& a, const std::vector<unsigned char>& b) const
35    {
36        if (a.size() < b.size()) return true;
37        if (a.size() > b.size()) return false;
38        return a < b;
39    }
40};
41
42struct TaprootSpendData
43{
44    /** The BIP341 internal key. */
45    XOnlyPubKey internal_key;
46    /** The Merkle root of the script tree (0 if no scripts). */
47    uint256 merkle_root;
48    /** Map from (script, leaf_version) to (sets of) control blocks.
49     *  More than one control block for a given script is only possible if it
50     *  appears in multiple branches of the tree. We keep them all so that
51     *  inference can reconstruct the full tree. Within each set, the control
52     *  blocks are sorted by size, so that the signing logic can easily
53     *  prefer the cheapest one. */
54    std::map<std::pair<std::vector<unsigned char>, int>, std::set<std::vector<unsigned char>, ShortestVectorFirstComparator>> scripts;
55    /** Merge other TaprootSpendData (for the same scriptPubKey) into this. */
56    void Merge(TaprootSpendData other);
57};
58
59/** Utility class to construct Taproot outputs from internal key and script tree. */
60class TaprootBuilder
61{
62private:
63    /** Information about a tracked leaf in the Merkle tree. */
64    struct LeafInfo
65    {
66        std::vector<unsigned char> script;   //!< The script.
67        int leaf_version;                    //!< The leaf version for that script.
68        std::vector<uint256> merkle_branch;  //!< The hashing partners above this leaf.
69    };
70
71    /** Information associated with a node in the Merkle tree. */
72    struct NodeInfo
73    {
74        /** Merkle hash of this node. */
75        uint256 hash;
76        /** Tracked leaves underneath this node (either from the node itself, or its children).
77         *  The merkle_branch field of each is the partners to get to *this* node. */
78        std::vector<LeafInfo> leaves;
79    };
80    /** Whether the builder is in a valid state so far. */
81    bool m_valid = true;
82
83    /** The current state of the builder.
84     *
85     * For each level in the tree, one NodeInfo object may be present. m_branch[0]
86     * is information about the root; further values are for deeper subtrees being
87     * explored.
88     *
89     * For every right branch taken to reach the position we're currently
90     * working in, there will be a (non-nullopt) entry in m_branch corresponding
91     * to the left branch at that level.
92     *
93     * For example, imagine this tree:     - N0 -
94     *                                    /      \
95     *                                   N1      N2
96     *                                  /  \    /  \
97     *                                 A    B  C   N3
98     *                                            /  \
99     *                                           D    E
100     *
101     * Initially, m_branch is empty. After processing leaf A, it would become
102     * {nullopt, nullopt, A}. When processing leaf B, an entry at level 2 already
103     * exists, and it would thus be combined with it to produce a level 1 one,
104     * resulting in {nullopt, N1}. Adding C and D takes us to {nullopt, N1, C}
105     * and {nullopt, N1, C, D} respectively. When E is processed, it is combined
106     * with D, and then C, and then N1, to produce the root, resulting in {N0}.
107     *
108     * This structure allows processing with just O(log n) overhead if the leaves
109     * are computed on the fly.
110     *
111     * As an invariant, there can never be nullopt entries at the end. There can
112     * also not be more than 128 entries (as that would mean more than 128 levels
113     * in the tree). The depth of newly added entries will always be at least
114     * equal to the current size of m_branch (otherwise it does not correspond
115     * to a depth-first traversal of a tree). m_branch is only empty if no entries
116     * have ever be processed. m_branch having length 1 corresponds to being done.
117     */
118    std::vector<std::optional<NodeInfo>> m_branch;
119
120    XOnlyPubKey m_internal_key;  //!< The internal key, set when finalizing.
121    XOnlyPubKey m_output_key;    //!< The output key, computed when finalizing.
122    bool m_parity;               //!< The tweak parity, computed when finalizing.
123
124    /** Combine information about a parent Merkle tree node from its child nodes. */
125    static NodeInfo Combine(NodeInfo&& a, NodeInfo&& b);
126    /** Insert information about a node at a certain depth, and propagate information up. */
127    void Insert(NodeInfo&& node, int depth);
128
129public:
130    /** Add a new script at a certain depth in the tree. Add() operations must be called
131     *  in depth-first traversal order of binary tree. If track is true, it will be included in
132     *  the GetSpendData() output. */
133    TaprootBuilder& Add(int depth, std::span<const unsigned char> script, int leaf_version, bool track = true);
134    /** Like Add(), but for a Merkle node with a given hash to the tree. */
135    TaprootBuilder& AddOmitted(int depth, const uint256& hash);
136    /** Finalize the construction. Can only be called when IsComplete() is true.
137        internal_key.IsFullyValid() must be true. */
138    TaprootBuilder& Finalize(const XOnlyPubKey& internal_key);
139
140    /** Return true if so far all input was valid. */
141    bool IsValid() const { return m_valid; }
142    /** Return whether there were either no leaves, or the leaves form a Huffman tree. */
143    bool IsComplete() const { return m_valid && (m_branch.size() == 0 || (m_branch.size() == 1 && m_branch[0].has_value())); }
144    /** Compute scriptPubKey (after Finalize()). */
145    WitnessV1Taproot GetOutput();
146    /** Check if a list of depths is legal (will lead to IsComplete()). */
147    static bool ValidDepths(const std::vector<int>& depths);
148    /** Compute spending data (after Finalize()). */
149    TaprootSpendData GetSpendData() const;
150    /** Returns a vector of tuples representing the depth, leaf version, and script */
151    std::vector<std::tuple<uint8_t, uint8_t, std::vector<unsigned char>>> GetTreeTuples() const;
152    /** Returns true if there are any tapscripts */
153    bool HasScripts() const { return !m_branch.empty(); }
154
155    bool operator==(const TaprootBuilder& other) const { return GetTreeTuples() == other.GetTreeTuples(); }
156};
157
158/** Given a TaprootSpendData and the output key, reconstruct its script tree.
159 *
160 * If the output doesn't match the spenddata, or if the data in spenddata is incomplete,
161 * std::nullopt is returned. Otherwise, a vector of (depth, script, leaf_ver) tuples is
162 * returned, corresponding to a depth-first traversal of the script tree.
163 */
164std::optional<std::vector<std::tuple<int, std::vector<unsigned char>, int>>> InferTaprootTree(const TaprootSpendData& spenddata, const XOnlyPubKey& output);
165
166/** An interface to be implemented by keystores that support signing. */
167class SigningProvider
168{
169public:
170    virtual ~SigningProvider() = default;
171    virtual bool GetCScript(const CScriptID &scriptid, CScript& script) const { return false; }
172    virtual bool HaveCScript(const CScriptID &scriptid) const { return false; }
173    virtual bool GetPubKey(const CKeyID &address, CPubKey& pubkey) const { return false; }
174    virtual bool GetKey(const CKeyID &address, CKey& key) const { return false; }
175    virtual bool HaveKey(const CKeyID &address) const { return false; }
176    virtual bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const { return false; }
177    virtual bool GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const { return false; }
178    virtual bool GetTaprootBuilder(const XOnlyPubKey& output_key, TaprootBuilder& builder) const { return false; }
179    virtual std::vector<CPubKey> GetMuSig2ParticipantPubkeys(const CPubKey& pubkey) const { return {}; }
180    virtual std::map<CPubKey, std::vector<CPubKey>> GetAllMuSig2ParticipantPubkeys() const {return {}; }
181    virtual void SetMuSig2SecNonce(const uint256& id, MuSig2SecNonce&& nonce) const {}
182    virtual std::optional<std::reference_wrapper<MuSig2SecNonce>> GetMuSig2SecNonce(const uint256& session_id) const { return std::nullopt; }
183    virtual void DeleteMuSig2Session(const uint256& session_id) const {}
184
185    bool GetKeyByXOnly(const XOnlyPubKey& pubkey, CKey& key) const
186    {
187        for (const auto& id : pubkey.GetKeyIDs()) {
188            if (GetKey(id, key)) return true;
189        }
190        return false;
191    }
192
193    bool GetPubKeyByXOnly(const XOnlyPubKey& pubkey, CPubKey& out) const
194    {
195        for (const auto& id : pubkey.GetKeyIDs()) {
196            if (GetPubKey(id, out)) return true;
197        }
198        return false;
199    }
200
201    bool GetKeyOriginByXOnly(const XOnlyPubKey& pubkey, KeyOriginInfo& info) const
202    {
203        for (const auto& id : pubkey.GetKeyIDs()) {
204            if (GetKeyOrigin(id, info)) return true;
205        }
206        return false;
207    }
208};
209
210extern const SigningProvider& DUMMY_SIGNING_PROVIDER;
211
212class HidingSigningProvider : public SigningProvider
213{
214private:
215    const bool m_hide_secret;
216    const bool m_hide_origin;
217    const SigningProvider* m_provider;
218
219public:
220    HidingSigningProvider(const SigningProvider* provider, bool hide_secret, bool hide_origin) : m_hide_secret(hide_secret), m_hide_origin(hide_origin), m_provider(provider) {}
221    bool GetCScript(const CScriptID& scriptid, CScript& script) const override;
222    bool GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const override;
223    bool GetKey(const CKeyID& keyid, CKey& key) const override;
224    bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const override;
225    bool GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const override;
226    bool GetTaprootBuilder(const XOnlyPubKey& output_key, TaprootBuilder& builder) const override;
227    std::vector<CPubKey> GetMuSig2ParticipantPubkeys(const CPubKey& pubkey) const override;
228    std::map<CPubKey, std::vector<CPubKey>> GetAllMuSig2ParticipantPubkeys() const override;
229    void SetMuSig2SecNonce(const uint256& id, MuSig2SecNonce&& nonce) const override;
230    std::optional<std::reference_wrapper<MuSig2SecNonce>> GetMuSig2SecNonce(const uint256& session_id) const override;
231    void DeleteMuSig2Session(const uint256& session_id) const override;
232};
233
234struct FlatSigningProvider final : public SigningProvider
235{
236    std::map<CScriptID, CScript> scripts;
237    std::map<CKeyID, CPubKey> pubkeys;
238    std::map<CKeyID, std::pair<CPubKey, KeyOriginInfo>> origins;
239    std::map<CKeyID, CKey> keys;
240    std::map<XOnlyPubKey, TaprootBuilder> tr_trees; /** Map from output key to Taproot tree (which can then make the TaprootSpendData */
241    std::map<CPubKey, std::vector<CPubKey>> aggregate_pubkeys; /** MuSig2 aggregate pubkeys */
242    std::map<uint256, MuSig2SecNonce>* musig2_secnonces{nullptr};
243
244    bool GetCScript(const CScriptID& scriptid, CScript& script) const override;
245    bool GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const override;
246    bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const override;
247    bool HaveKey(const CKeyID &keyid) const override;
248    bool GetKey(const CKeyID& keyid, CKey& key) const override;
249    bool GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const override;
250    bool GetTaprootBuilder(const XOnlyPubKey& output_key, TaprootBuilder& builder) const override;

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

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