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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.

bitcoin / bitcoinstable

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▤ chacha20poly1305.cppGuide

▤ chacha20poly1305.hGuide

▤ hkdf_sha256_32.cppGuide

▤ hkdf_sha256_32.hGuide

▤ hmac_sha256.cppGuide

▤ hmac_sha256.hGuide

▤ hmac_sha512.cppGuide

▤ sha256_arm_shani.cpp

▤ sha256_avx2.cpp

▤ sha256_sse4.cpp

▤ sha256_sse41.cpp

▤ sha256_x86_shani.cpp

▤ arith_uint256.hGuide

▤ bitcoin-chainstate.cpp

▤ bitcoin-cli-res.rc

▤ bitcoin-cli.cppGuide

▤ bitcoin-res.rc

▤ bitcoin-tx-res.rc

▤ bitcoin-tx.cpp

▤ bitcoin-util-res.rc

▤ bitcoin-util.cpp

▤ bitcoin-wallet-res.rc

▤ blockencodings.cppGuide

▤ blockencodings.hGuide

▤ blockfilter.cppGuide

▤ blockfilter.hGuide

▤ chain.cppGuide

▤ chain.h

▤ chainparams.cppGuide

▤ chainparams.hGuide

▤ chainparamsbase.cppGuide

▤ chainparamsbase.hGuide

▤ chainparamsseeds.h

▤ checkqueue.hGuide

▤ clientversion.cppGuide

▤ clientversion.hGuide

▤ cluster_linearize.h

▤ CMakeLists.txt

▤ coins.cppGuide

▤ coins.hGuide

▤ compressor.cppGuide

▤ compressor.hGuide

▤ core_io.cpp

▤ core_io.hGuide

▤ core_memusage.hGuide

▤ cuckoocache.h

▤ dbwrapper.cpp

▤ dbwrapper.hGuide

▤ deploymentinfo.cppGuide

▤ deploymentinfo.hGuide

▤ deploymentstatus.cppGuide

▤ deploymentstatus.hGuide

▤ dummywallet.cppGuide

▤ external_signer.cpp

▤ external_signer.hGuide

▤ merkleblock.cppGuide

▤ merkleblock.hGuide

▤ musig.cpp

▤ musig.hGuide

▤ net_permissions.cppGuide

▤ net_permissions.hGuide

▤ net_processing.cppGuide

▤ netaddress.cppGuide

▤ netmessagemaker.hGuide

▤ noui.cppGuide

▤ noui.hGuide

▤ outputtype.cppGuide

▤ private_broadcast.cpp

▤ private_broadcast.h

▤ semaphore_grant.hGuide

▤ threadsafety.hGuide

▤ tinyformat.h

▤ torcontrol.cppGuide

▤ validation.cppGuide

▤ validation.h

▤ validationinterface.cpp

▤ validationinterface.h

▤ versionbits_impl.hGuide

▤ versionbits.cpp

▤ versionbits.hGuide

▤ walletinitinterface.hGuide

▤ CMakeLists.txtGuide

▤ libbitcoinkernel.pc.in

bitcoin / src / crypto / chacha20.cpp

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10,389 bytes · SHA-256 c412e83b29f088bd… · View upstream ↗

251        if (!j12) ++j13;
252
253        WriteLE32(c + 0, x0);
254        WriteLE32(c + 4, x1);
255        WriteLE32(c + 8, x2);
256        WriteLE32(c + 12, x3);
257        WriteLE32(c + 16, x4);
258        WriteLE32(c + 20, x5);
259        WriteLE32(c + 24, x6);
260        WriteLE32(c + 28, x7);
261        WriteLE32(c + 32, x8);
262        WriteLE32(c + 36, x9);
263        WriteLE32(c + 40, x10);
264        WriteLE32(c + 44, x11);
265        WriteLE32(c + 48, x12);
266        WriteLE32(c + 52, x13);
267        WriteLE32(c + 56, x14);
268        WriteLE32(c + 60, x15);
269
270        if (blocks == 1) {
271            input[8] = j12;
272            input[9] = j13;
273            return;
274        }
275        blocks -= 1;
276        c += BLOCKLEN;
277        m += BLOCKLEN;
278    }
279}
280
281void ChaCha20::Keystream(std::span<std::byte> out) noexcept
282{
283    if (out.empty()) return;
284    if (m_bufleft) {
285        unsigned reuse = std::min<size_t>(m_bufleft, out.size());
286        std::copy(m_buffer.end() - m_bufleft, m_buffer.end() - m_bufleft + reuse, out.begin());
287        m_bufleft -= reuse;
288        out = out.subspan(reuse);
289    }
290    if (out.size() >= m_aligned.BLOCKLEN) {
291        size_t blocks = out.size() / m_aligned.BLOCKLEN;
292        m_aligned.Keystream(out.first(blocks * m_aligned.BLOCKLEN));
293        out = out.subspan(blocks * m_aligned.BLOCKLEN);
294    }
295    if (!out.empty()) {
296        m_aligned.Keystream(m_buffer);
297        std::copy(m_buffer.begin(), m_buffer.begin() + out.size(), out.begin());
298        m_bufleft = m_aligned.BLOCKLEN - out.size();
299    }
300}
301
302void ChaCha20::Crypt(std::span<const std::byte> input, std::span<std::byte> output) noexcept
303{
304    assert(input.size() == output.size());
305
306    if (!input.size()) return;
307    if (m_bufleft) {
308        unsigned reuse = std::min<size_t>(m_bufleft, input.size());
309        for (unsigned i = 0; i < reuse; i++) {
310            output[i] = input[i] ^ m_buffer[m_aligned.BLOCKLEN - m_bufleft + i];
311        }
312        m_bufleft -= reuse;
313        output = output.subspan(reuse);
314        input = input.subspan(reuse);
315    }
316    if (input.size() >= m_aligned.BLOCKLEN) {
317        size_t blocks = input.size() / m_aligned.BLOCKLEN;
318        m_aligned.Crypt(input.first(blocks * m_aligned.BLOCKLEN), output.first(blocks * m_aligned.BLOCKLEN));
319        output = output.subspan(blocks * m_aligned.BLOCKLEN);
320        input = input.subspan(blocks * m_aligned.BLOCKLEN);
321    }
322    if (!input.empty()) {
323        m_aligned.Keystream(m_buffer);
324        for (unsigned i = 0; i < input.size(); i++) {
325            output[i] = input[i] ^ m_buffer[i];
326        }
327        m_bufleft = m_aligned.BLOCKLEN - input.size();
328    }
329}
330
331ChaCha20::~ChaCha20()
332{
333    memory_cleanse(m_buffer.data(), m_buffer.size());
334}
335
336void ChaCha20::SetKey(std::span<const std::byte> key) noexcept
337{
338    m_aligned.SetKey(key);
339    m_bufleft = 0;
340    memory_cleanse(m_buffer.data(), m_buffer.size());
341}
342
343FSChaCha20::FSChaCha20(std::span<const std::byte> key, uint32_t rekey_interval) noexcept :
344    m_chacha20(key), m_rekey_interval(rekey_interval)
345{
346    assert(key.size() == KEYLEN);
347}
348
349void FSChaCha20::Crypt(std::span<const std::byte> input, std::span<std::byte> output) noexcept
350{
351    assert(input.size() == output.size());
352
353    // Invoke internal stream cipher for actual encryption/decryption.
354    m_chacha20.Crypt(input, output);
355
356    // Rekey after m_rekey_interval encryptions/decryptions.
357    if (++m_chunk_counter == m_rekey_interval) {
358        // Get new key from the stream cipher.
359        std::byte new_key[KEYLEN];
360        m_chacha20.Keystream(new_key);
361        // Update its key.
362        m_chacha20.SetKey(new_key);
363        // Wipe the key (a copy remains inside m_chacha20, where it'll be wiped on the next rekey
364        // or on destruction).
365        memory_cleanse(new_key, sizeof(new_key));
366        // Set the nonce for the new section of output.
367        m_chacha20.Seek({0, ++m_rekey_counter}, 0);
368        // Reset the chunk counter.
369        m_chunk_counter = 0;
370    }
371}
372

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440 guided files · 2,580 pending. Guides cover key sections, not every line.

cmake/bitcoin-build-config.h.in src/consensus/amount.h src/consensus/consensus.h src/primitives/block.h src/primitives/transaction.h src/crypto/sha256.h src/util/moneystr.h src/clientversion.h src/uint256.h src/script/script.h src/policy/policy.h CMakeLists.txt README.md COPYING src/consensus/tx_check.cpp src/consensus/tx_verify.cpp src/consensus/merkle.cpp src/pow.cpp src/validation.cpp src/script/interpreter.cpp src/script/solver.cpp src/script/sign.cpp src/key_io.cpp src/net.cpp src/net_processing.cpp src/netaddress.cpp src/protocol.h src/wallet/wallet.cpp src/wallet/spend.cpp

← Previous 250 linesCode page 2

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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