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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.

6,768 bytes · SHA-256 57753fcb9c351688… · View upstream ↗

1// Copyright (c) 2019-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 <crypto/common.h>
6#include <crypto/poly1305.h>
7
8namespace poly1305_donna {
9
10// Based on the public domain implementation by Andrew Moon
11// poly1305-donna-32.h from https://github.com/floodyberry/poly1305-donna
12
13void poly1305_init(poly1305_context *st, const unsigned char key[32]) noexcept {
14    /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */
15    st->r[0] = (ReadLE32(&key[ 0])     ) & 0x3ffffff;
16    st->r[1] = (ReadLE32(&key[ 3]) >> 2) & 0x3ffff03;
17    st->r[2] = (ReadLE32(&key[ 6]) >> 4) & 0x3ffc0ff;
18    st->r[3] = (ReadLE32(&key[ 9]) >> 6) & 0x3f03fff;
19    st->r[4] = (ReadLE32(&key[12]) >> 8) & 0x00fffff;
20
21    /* h = 0 */
22    st->h[0] = 0;
23    st->h[1] = 0;
24    st->h[2] = 0;
25    st->h[3] = 0;
26    st->h[4] = 0;
27
28    /* save pad for later */
29    st->pad[0] = ReadLE32(&key[16]);
30    st->pad[1] = ReadLE32(&key[20]);
31    st->pad[2] = ReadLE32(&key[24]);
32    st->pad[3] = ReadLE32(&key[28]);
33
34    st->leftover = 0;
35    st->final = 0;
36}
37
38static void poly1305_blocks(poly1305_context *st, const unsigned char *m, size_t bytes) noexcept {
39    const uint32_t hibit = (st->final) ? 0 : (1UL << 24); /* 1 << 128 */
40    uint32_t r0,r1,r2,r3,r4;
41    uint32_t s1,s2,s3,s4;
42    uint32_t h0,h1,h2,h3,h4;
43    uint64_t d0,d1,d2,d3,d4;
44    uint32_t c;
45
46    r0 = st->r[0];
47    r1 = st->r[1];
48    r2 = st->r[2];
49    r3 = st->r[3];
50    r4 = st->r[4];
51
52    s1 = r1 * 5;
53    s2 = r2 * 5;
54    s3 = r3 * 5;
55    s4 = r4 * 5;
56
57    h0 = st->h[0];
58    h1 = st->h[1];
59    h2 = st->h[2];
60    h3 = st->h[3];
61    h4 = st->h[4];
62
63    while (bytes >= POLY1305_BLOCK_SIZE) {
64        /* h += m[i] */
65        h0 += (ReadLE32(m+ 0)     ) & 0x3ffffff;
66        h1 += (ReadLE32(m+ 3) >> 2) & 0x3ffffff;
67        h2 += (ReadLE32(m+ 6) >> 4) & 0x3ffffff;
68        h3 += (ReadLE32(m+ 9) >> 6) & 0x3ffffff;
69        h4 += (ReadLE32(m+12) >> 8) | hibit;
70
71        /* h *= r */
72        d0 = ((uint64_t)h0 * r0) + ((uint64_t)h1 * s4) + ((uint64_t)h2 * s3) + ((uint64_t)h3 * s2) + ((uint64_t)h4 * s1);
73        d1 = ((uint64_t)h0 * r1) + ((uint64_t)h1 * r0) + ((uint64_t)h2 * s4) + ((uint64_t)h3 * s3) + ((uint64_t)h4 * s2);
74        d2 = ((uint64_t)h0 * r2) + ((uint64_t)h1 * r1) + ((uint64_t)h2 * r0) + ((uint64_t)h3 * s4) + ((uint64_t)h4 * s3);
75        d3 = ((uint64_t)h0 * r3) + ((uint64_t)h1 * r2) + ((uint64_t)h2 * r1) + ((uint64_t)h3 * r0) + ((uint64_t)h4 * s4);
76        d4 = ((uint64_t)h0 * r4) + ((uint64_t)h1 * r3) + ((uint64_t)h2 * r2) + ((uint64_t)h3 * r1) + ((uint64_t)h4 * r0);
77
78        /* (partial) h %= p */
79                      c = (uint32_t)(d0 >> 26); h0 = (uint32_t)d0 & 0x3ffffff;
80        d1 += c;      c = (uint32_t)(d1 >> 26); h1 = (uint32_t)d1 & 0x3ffffff;
81        d2 += c;      c = (uint32_t)(d2 >> 26); h2 = (uint32_t)d2 & 0x3ffffff;
82        d3 += c;      c = (uint32_t)(d3 >> 26); h3 = (uint32_t)d3 & 0x3ffffff;
83        d4 += c;      c = (uint32_t)(d4 >> 26); h4 = (uint32_t)d4 & 0x3ffffff;
84        h0 += c * 5;  c =           (h0 >> 26); h0 =           h0 & 0x3ffffff;
85        h1 += c;
86
87        m += POLY1305_BLOCK_SIZE;
88        bytes -= POLY1305_BLOCK_SIZE;
89    }
90
91    st->h[0] = h0;
92    st->h[1] = h1;
93    st->h[2] = h2;
94    st->h[3] = h3;
95    st->h[4] = h4;
96}
97
98void poly1305_finish(poly1305_context *st, unsigned char mac[16]) noexcept {
99    uint32_t h0,h1,h2,h3,h4,c;
100    uint32_t g0,g1,g2,g3,g4;
101    uint64_t f;
102    uint32_t mask;
103
104    /* process the remaining block */
105    if (st->leftover) {
106        size_t i = st->leftover;
107        st->buffer[i++] = 1;
108        for (; i < POLY1305_BLOCK_SIZE; i++) {
109            st->buffer[i] = 0;
110        }
111        st->final = 1;
112        poly1305_blocks(st, st->buffer, POLY1305_BLOCK_SIZE);
113    }
114
115    /* fully carry h */
116    h0 = st->h[0];
117    h1 = st->h[1];
118    h2 = st->h[2];
119    h3 = st->h[3];
120    h4 = st->h[4];
121
122                 c = h1 >> 26; h1 = h1 & 0x3ffffff;
123    h2 +=     c; c = h2 >> 26; h2 = h2 & 0x3ffffff;
124    h3 +=     c; c = h3 >> 26; h3 = h3 & 0x3ffffff;
125    h4 +=     c; c = h4 >> 26; h4 = h4 & 0x3ffffff;
126    h0 += c * 5; c = h0 >> 26; h0 = h0 & 0x3ffffff;
127    h1 +=     c;
128
129    /* compute h + -p */
130    g0 = h0 + 5; c = g0 >> 26; g0 &= 0x3ffffff;
131    g1 = h1 + c; c = g1 >> 26; g1 &= 0x3ffffff;
132    g2 = h2 + c; c = g2 >> 26; g2 &= 0x3ffffff;
133    g3 = h3 + c; c = g3 >> 26; g3 &= 0x3ffffff;
134    g4 = h4 + c - (1UL << 26);
135
136    /* select h if h < p, or h + -p if h >= p */
137    mask = (g4 >> ((sizeof(uint32_t) * 8) - 1)) - 1;
138    g0 &= mask;
139    g1 &= mask;
140    g2 &= mask;
141    g3 &= mask;
142    g4 &= mask;
143    mask = ~mask;
144    h0 = (h0 & mask) | g0;
145    h1 = (h1 & mask) | g1;
146    h2 = (h2 & mask) | g2;
147    h3 = (h3 & mask) | g3;
148    h4 = (h4 & mask) | g4;
149
150    /* h = h % (2^128) */
151    h0 = ((h0      ) | (h1 << 26)) & 0xffffffff;
152    h1 = ((h1 >>  6) | (h2 << 20)) & 0xffffffff;
153    h2 = ((h2 >> 12) | (h3 << 14)) & 0xffffffff;
154    h3 = ((h3 >> 18) | (h4 <<  8)) & 0xffffffff;
155
156    /* mac = (h + pad) % (2^128) */
157    f = (uint64_t)h0 + st->pad[0]            ; h0 = (uint32_t)f;
158    f = (uint64_t)h1 + st->pad[1] + (f >> 32); h1 = (uint32_t)f;
159    f = (uint64_t)h2 + st->pad[2] + (f >> 32); h2 = (uint32_t)f;
160    f = (uint64_t)h3 + st->pad[3] + (f >> 32); h3 = (uint32_t)f;
161
162    WriteLE32(mac +  0, h0);
163    WriteLE32(mac +  4, h1);
164    WriteLE32(mac +  8, h2);
165    WriteLE32(mac + 12, h3);
166
167    /* zero out the state */
168    st->h[0] = 0;
169    st->h[1] = 0;
170    st->h[2] = 0;
171    st->h[3] = 0;
172    st->h[4] = 0;
173    st->r[0] = 0;
174    st->r[1] = 0;
175    st->r[2] = 0;
176    st->r[3] = 0;
177    st->r[4] = 0;
178    st->pad[0] = 0;
179    st->pad[1] = 0;
180    st->pad[2] = 0;
181    st->pad[3] = 0;
182}
183
184void poly1305_update(poly1305_context *st, const unsigned char *m, size_t bytes) noexcept {
185    size_t i;
186
187    /* handle leftover */
188    if (st->leftover) {
189        size_t want = (POLY1305_BLOCK_SIZE - st->leftover);
190        if (want > bytes) {
191            want = bytes;
192        }
193        for (i = 0; i < want; i++) {
194            st->buffer[st->leftover + i] = m[i];
195        }
196        bytes -= want;
197        m += want;
198        st->leftover += want;
199        if (st->leftover < POLY1305_BLOCK_SIZE) return;
200        poly1305_blocks(st, st->buffer, POLY1305_BLOCK_SIZE);
201        st->leftover = 0;
202    }
203
204    /* process full blocks */
205    if (bytes >= POLY1305_BLOCK_SIZE) {
206        size_t want = (bytes & ~(POLY1305_BLOCK_SIZE - 1));
207        poly1305_blocks(st, m, want);
208        m += want;
209        bytes -= want;
210    }
211
212    /* store leftover */
213    if (bytes) {
214        for (i = 0; i < bytes; i++) {
215            st->buffer[st->leftover + i] = m[i];
216        }
217        st->leftover += bytes;
218    }
219}
220
221}  // namespace poly1305_donna
222

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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