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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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12,699 bytes · SHA-256 530f3bbe4ef5dc35… · View upstream ↗

1// Copyright (c) 2009-2010 Satoshi Nakamoto
2// Copyright (c) 2009-present The Bitcoin Core developers
3// Copyright (c) 2017 The Zcash developers
4// Distributed under the MIT software license, see the accompanying
5// file COPYING or http://www.opensource.org/licenses/mit-license.php.
6
7#ifndef BITCOIN_PUBKEY_H
8#define BITCOIN_PUBKEY_H
9
10#include <hash.h>
11#include <serialize.h>
12#include <span.h>
13#include <uint256.h>
14
15#include <cstring>
16#include <optional>
17#include <vector>
18
19inline constexpr unsigned int BIP32_EXTKEY_SIZE = 74;
20inline constexpr unsigned int BIP32_EXTKEY_WITH_VERSION_SIZE = 78;
21
22using KeyFingerprint = std::array<unsigned char, 4>;
23
24/** A reference to a CKey: the Hash160 of its serialized public key */
25class CKeyID : public uint160
26{
27public:
28    CKeyID() : uint160() {}
29    explicit CKeyID(const uint160& in) : uint160(in) {}
30    KeyFingerprint fingerprint() const
31    {
32        KeyFingerprint ret;
33        std::copy_n(begin(), ret.size(), ret.begin());
34        return ret;
35    }
36};
37
38/** An encapsulated public key. */
39class CPubKey
40{
41public:
42    /**
43     * secp256k1:
44     */
45    static constexpr unsigned int SIZE                   = 65;
46    static constexpr unsigned int COMPRESSED_SIZE        = 33;
47    static constexpr unsigned int SIGNATURE_SIZE         = 72;
48    static constexpr unsigned int COMPACT_SIGNATURE_SIZE = 65;
49    /**
50     * see www.keylength.com
51     * script supports up to 75 for single byte push
52     */
53    static_assert(
54        SIZE >= COMPRESSED_SIZE,
55        "COMPRESSED_SIZE is larger than SIZE");
56
57private:
58
59    /**
60     * Just store the serialized data.
61     * Its length can very cheaply be computed from the first byte.
62     */
63    unsigned char vch[SIZE];
64
65    //! Compute the length of a pubkey with a given first byte.
66    unsigned int static GetLen(unsigned char chHeader)
67    {
68        if (chHeader == 2 || chHeader == 3)
69            return COMPRESSED_SIZE;
70        if (chHeader == 4 || chHeader == 6 || chHeader == 7)
71            return SIZE;
72        return 0;
73    }
74
75    //! Set this key data to be invalid
76    void Invalidate()
77    {
78        vch[0] = 0xFF;
79    }
80
81public:
82
83    bool static ValidSize(const std::vector<unsigned char> &vch) {
84      return vch.size() > 0 && GetLen(vch[0]) == vch.size();
85    }
86
87    //! Construct an invalid public key.
88    CPubKey()
89    {
90        Invalidate();
91    }
92
93    //! Initialize a public key using begin/end iterators to byte data.
94    template <typename T>
95    void Set(const T pbegin, const T pend)
96    {
97        int len = pend == pbegin ? 0 : GetLen(pbegin[0]);
98        if (len && len == (pend - pbegin))
99            memcpy(vch, (unsigned char*)&pbegin[0], len);
100        else
101            Invalidate();
102    }
103
104    //! Construct a public key using begin/end iterators to byte data.
105    template <typename T>
106    CPubKey(const T pbegin, const T pend)
107    {
108        Set(pbegin, pend);
109    }
110
111    //! Construct a public key from a byte vector.
112    explicit CPubKey(std::span<const uint8_t> _vch)
113    {
114        Set(_vch.begin(), _vch.end());
115    }
116
117    //! Simple read-only vector-like interface to the pubkey data.
118    unsigned int size() const { return GetLen(vch[0]); }
119    const unsigned char* data() const { return vch; }
120    const unsigned char* begin() const { return vch; }
121    const unsigned char* end() const { return vch + size(); }
122    const unsigned char& operator[](unsigned int pos) const { return vch[pos]; }
123
124    //! Comparator implementation.
125    friend bool operator==(const CPubKey& a, const CPubKey& b)
126    {
127        return a.vch[0] == b.vch[0] &&
128               memcmp(a.vch, b.vch, a.size()) == 0;
129    }
130    friend bool operator<(const CPubKey& a, const CPubKey& b)
131    {
132        return a.vch[0] < b.vch[0] ||
133               (a.vch[0] == b.vch[0] && memcmp(a.vch, b.vch, a.size()) < 0);
134    }
135    friend bool operator>(const CPubKey& a, const CPubKey& b)
136    {
137        return a.vch[0] > b.vch[0] ||
138               (a.vch[0] == b.vch[0] && memcmp(a.vch, b.vch, a.size()) > 0);
139    }
140
141    //! Implement serialization, as if this was a byte vector.
142    template <typename Stream>
143    void Serialize(Stream& s) const
144    {
145        unsigned int len = size();
146        ::WriteCompactSize(s, len);
147        s << std::span{vch, len};
148    }
149    template <typename Stream>
150    void Unserialize(Stream& s)
151    {
152        const unsigned int len(::ReadCompactSize(s));
153        if (len <= SIZE) {
154            s >> std::span{vch, len};
155            if (len != size()) {
156                Invalidate();
157            }
158        } else {
159            // invalid pubkey, skip available data
160            s.ignore(len);
161            Invalidate();
162        }
163    }
164
165    //! Get the KeyID of this public key (hash of its serialization)
166    CKeyID GetID() const
167    {
168        return CKeyID(Hash160(std::span{vch}.first(size())));
169    }
170
171    //! Get the 256-bit hash of this public key.
172    uint256 GetHash() const
173    {
174        return Hash(std::span{vch}.first(size()));
175    }
176
177    /*
178     * Check syntactic correctness.
179     *
180     * When setting a pubkey (Set()) or deserializing fails (its header bytes
181     * don't match the length of the data), the size is set to 0. Thus,
182     * by checking size, one can observe whether Set() or deserialization has
183     * failed.
184     *
185     * This does not check for more than that. In particular, it does not verify
186     * that the coordinates correspond to a point on the curve (see IsFullyValid()
187     * for that instead).
188     *
189     * Note that this is consensus critical as CheckECDSASignature() calls it!
190     */
191    bool IsValid() const
192    {
193        return size() > 0;
194    }
195
196    /** Check if a public key is a syntactically valid compressed or uncompressed key. */
197    bool IsValidNonHybrid() const noexcept
198    {
199        return size() > 0 && (vch[0] == 0x02 || vch[0] == 0x03 || vch[0] == 0x04);
200    }
201
202    //! fully validate whether this is a valid public key (more expensive than IsValid())
203    bool IsFullyValid() const;
204
205    //! Check whether this is a compressed public key.
206    bool IsCompressed() const
207    {
208        return size() == COMPRESSED_SIZE;
209    }
210
211    /**
212     * Verify a DER signature (~72 bytes).
213     * If this public key is not fully valid, the return value will be false.
214     */
215    bool Verify(const uint256& hash, const std::vector<unsigned char>& vchSig) const;
216
217    /**
218     * Check whether a signature is normalized (lower-S).
219     */
220    static bool CheckLowS(const std::vector<unsigned char>& vchSig);
221
222    //! Recover a public key from a compact signature.
223    bool RecoverCompact(const uint256& hash, const std::vector<unsigned char>& vchSig);
224
225    //! Turn this public key into an uncompressed public key.
226    bool Decompress();
227
228    //! Derive BIP32 child pubkey.
229    [[nodiscard]] bool Derive(CPubKey& pubkeyChild, ChainCode &ccChild, unsigned int nChild, const ChainCode& cc, uint256* bip32_tweak_out = nullptr) const;
230};
231
232class XOnlyPubKey
233{
234private:
235    uint256 m_keydata;
236
237public:
238    /** Nothing Up My Sleeve point H
239     *  Used as an internal key for provably disabling the key path spend
240     *  see BIP341 for more details */
241    static const XOnlyPubKey NUMS_H;
242
243    /** Construct an empty x-only pubkey. */
244    XOnlyPubKey() = default;
245
246    XOnlyPubKey(const XOnlyPubKey&) = default;
247    XOnlyPubKey& operator=(const XOnlyPubKey&) = default;
248
249    /** Determine if this pubkey is fully valid. This is true for approximately 50% of all
250     *  possible 32-byte arrays. If false, VerifySchnorr, CheckTapTweak and CreateTapTweak

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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