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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.

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1#!/usr/bin/env python3
2# Copyright (c) 2015-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"""Dummy Socks5 server for testing."""
6
7import select
8import socket
9import threading
10import queue
11import logging
12
13from .netutil import (
14    format_addr_port,
15    format_sock,
16    set_ephemeral_port_range,
17)
18
19logger = logging.getLogger("TestFramework.socks5")
20
21# Protocol constants
22class Command:
23    CONNECT = 0x01
24
25class AddressType:
26    IPV4 = 0x01
27    DOMAINNAME = 0x03
28    IPV6 = 0x04
29
30# Utility functions
31def recvall(s, n):
32    """Receive n bytes from a socket, or fail."""
33    rv = bytearray()
34    while n > 0:
35        d = s.recv(n)
36        if not d:
37            raise IOError('Unexpected end of stream')
38        rv.extend(d)
39        n -= len(d)
40    return rv
41
42def sendall(s, data):
43    """Send all data to a socket, or fail."""
44    sent = 0
45    while sent < len(data):
46        _, wlist, _ = select.select([], [s], [])
47        if len(wlist) > 0:
48            n = s.send(data[sent:])
49            if n == 0:
50                raise IOError('send() on socket returned 0')
51            sent += n
52
53def forward_sockets(a, b, wakeup_socket, serv):
54    """Forwards data between sockets a and b until EOF, error, or shutdown.
55
56    Monitors wakeup_socket for a shutdown signal and checks serv.is_running()
57    to exit gracefully when the server is stopping.
58    """
59    # Prefix messages with e.g.:
60    # forward_sockets(a{remote=127.0.0.1:36935, local=127.0.0.1:9050} <-> b{local=127.0.0.1:33424, remote=127.0.0.1:8333})
61    log_prefix = ("forward_sockets("
62                  f"a{{remote={format_sock(a, local=False)}, local={format_sock(a, local=True)}}} <-> "
63                  f"b{{local={format_sock(b, local=True)}, remote={format_sock(b, local=False)}}}): ")
64
65    # Mark as non-blocking so that we do not end up in a deadlock-like situation
66    # where we block and wait on data from `a` while there is data ready to be
67    # received on `b` and forwarded to `a`. And at the same time the application
68    # at `a` is not sending anything because it waits for the data from `b` to
69    # respond.
70    a.setblocking(False)
71    b.setblocking(False)
72    sockets = [a, b, wakeup_socket]
73    while True:
74        # Blocking select with timeout
75        rlist, _, xlist = select.select(sockets, [], sockets, 2)
76        if not serv.is_running():
77            logger.debug(f"{log_prefix}Exit due to shutdown")
78            return
79        if len(xlist) > 0:
80            raise IOError(f"{log_prefix}Exceptional condition on socket")
81        for s in rlist:
82            try:
83                data = s.recv(4096)
84                if data is None or len(data) == 0:
85                    return
86                if s == a:
87                    sendall(b, data)
88                elif s == b:
89                    sendall(a, data)
90            except (BrokenPipeError, ConnectionResetError) as e:
91                logger.debug(f"{log_prefix}cannot send or receive data on socket {'a' if s == a else 'b'}: {str(e)}")
92                return
93
94# Implementation classes
95class Socks5Configuration():
96    """Proxy configuration."""
97    def __init__(self):
98        self.addr = None # Bind address (must be set)
99        self.af = socket.AF_INET # Bind address family
100        self.unauth = False  # Support unauthenticated
101        self.auth = False  # Support authentication
102        self.keep_alive = False  # Do not automatically close connections
103        # This function is called whenever a new connection arrives to the proxy
104        # and it decides where the connection is redirected to. It is passed:
105        # - the address the client requested to connect to
106        # - the port the client requested to connect to
107        # - the client's socket address as seen by the proxy, formatted as host:port
108        # It is supposed to return an object like:
109        # {
110        #     "actual_to_addr": "127.0.0.1"
111        #     "actual_to_port": 28276
112        # }
113        # or None.
114        # If it returns an object then the connection is redirected to actual_to_addr:actual_to_port.
115        # If it returns None, or destinations_factory itself is None then the connection is closed.
116        self.destinations_factory = None
117
118class Socks5Command():
119    """Information about an incoming socks5 command."""
120    def __init__(self, cmd, atyp, addr, port, username, password):
121        self.cmd = cmd # Command (one of Command.*)
122        self.atyp = atyp # Address type (one of AddressType.*)
123        self.addr = addr # Address
124        self.port = port # Port to connect to
125        self.username = username
126        self.password = password
127    def __repr__(self):
128        return 'Socks5Command(%s,%s,%s,%s,%s,%s)' % (self.cmd, self.atyp, self.addr, self.port, self.username, self.password)
129
130class Socks5Connection():
131    def __init__(self, serv, conn):
132        self.serv = serv
133        self.conn = conn
134        # Socket-pair used to wake up blocking forwarding select
135        # Note: a pipe could be used as well, but that does not work with select() on Windows
136        self.wakeup_socket_pair = socket.socketpair()
137        # Index of this handler (within the server)
138        self.handler_index = None
139
140    def handle(self):
141        """Handle socks5 request according to RFC1928."""
142        log_exception_prefix = "Socks5Connection.handle(): "
143        try:
144            proxy_client = format_sock(self.conn, local=False)
145            log_exception_prefix = ("Socks5Connection.handle("
146                                    f"client={proxy_client}, "
147                                    f"proxy={format_sock(self.conn, local=True)}): ")
148
149            # Verify socks version
150            ver = recvall(self.conn, 1)[0]
151            if ver != 0x05:
152                raise IOError('Invalid socks version %i' % ver)
153            # Choose authentication method
154            nmethods = recvall(self.conn, 1)[0]
155            methods = bytearray(recvall(self.conn, nmethods))
156            method = None
157            if 0x02 in methods and self.serv.conf.auth:
158                method = 0x02 # username/password
159            elif 0x00 in methods and self.serv.conf.unauth:
160                method = 0x00 # unauthenticated
161            if method is None:
162                raise IOError('No supported authentication method was offered')
163            # Send response
164            self.conn.sendall(bytearray([0x05, method]))
165            # Read authentication (optional)
166            username = None
167            password = None
168            if method == 0x02:
169                ver = recvall(self.conn, 1)[0]
170                if ver != 0x01:
171                    raise IOError('Invalid auth packet version %i' % ver)
172                ulen = recvall(self.conn, 1)[0]
173                username = str(recvall(self.conn, ulen))
174                plen = recvall(self.conn, 1)[0]
175                password = str(recvall(self.conn, plen))
176                # Send authentication response
177                self.conn.sendall(bytearray([0x01, 0x00]))
178
179            # Read connect request
180            ver, cmd, _, atyp = recvall(self.conn, 4)
181            if ver != 0x05:
182                raise IOError('Invalid socks version %i in connect request' % ver)
183            if cmd != Command.CONNECT:
184                raise IOError('Unhandled command %i in connect request' % cmd)
185
186            if atyp == AddressType.IPV4:
187                addr = recvall(self.conn, 4)
188            elif atyp == AddressType.DOMAINNAME:
189                n = recvall(self.conn, 1)[0]
190                addr = recvall(self.conn, n)
191            elif atyp == AddressType.IPV6:
192                addr = recvall(self.conn, 16)
193            else:
194                raise IOError('Unknown address type %i' % atyp)
195            port_hi,port_lo = recvall(self.conn, 2)
196            port = (port_hi << 8) | port_lo
197
198            # Reply SUCCESS before calling destinations_factory, so the client can finish
199            # establishing the connection and register the peer; factories that consult
200            # getpeerinfo depend on that order.
201            self.conn.sendall(bytearray([0x05, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]))
202
203            cmdin = Socks5Command(cmd, atyp, addr, port, username, password)
204            self.serv.queue.put(cmdin)
205            logger.debug('Proxy: %s', cmdin)
206
207            requested_to_addr = addr.decode("utf-8")
208            requested_to = format_addr_port(requested_to_addr, port)
209
210            if self.serv.is_running():
211                if self.serv.conf.destinations_factory is not None:
212                    dest = self.serv.conf.destinations_factory(requested_to_addr, port, proxy_client)
213                    if dest is not None:
214                        logger.debug(f"Serving connection to {requested_to}, will redirect it to "
215                                    f"{dest['actual_to_addr']}:{dest['actual_to_port']} instead")
216                        with socket.create_connection((dest["actual_to_addr"], dest["actual_to_port"])) as conn_to:
217                            forward_sockets(self.conn, conn_to, self.wakeup_socket_pair[1], self.serv)
218                            conn_to.close()
219                    else:
220                        logger.debug(f"Can't serve the connection to {requested_to}: the destinations factory returned None")
221                else:
222                    logger.debug(f"Can't serve the connection to {requested_to}: no destinations factory")
223
224            # Disconnect happens in the "finally" block below.
225
226        except (BrokenPipeError, ConnectionResetError) as e:
227            logger.debug(f"{log_exception_prefix}abnormal connection close: {str(e)}")
228        except Exception as e:
229            logger.exception(f"{log_exception_prefix}exception: {str(e)} (running {self.serv.is_running()})")
230            if self.serv.is_running():
231                self.serv.queue.put(e)
232        finally:
233            if not self.serv.keep_alive:
234                self.conn.close()
235            else:
236                logger.debug("Keeping client connection alive")
237            s0 = self.wakeup_socket_pair[0]
238            s1 = self.wakeup_socket_pair[1]
239            self.wakeup_socket_pair = None
240            try:
241                s0.close()
242                s1.close()
243            except OSError:
244                pass
245            self.serv.remove_handler(self.handler_index)
246            self.handler_index = None
247
248    def wakeup(self):
249        # Wake up the blocking forwarding select by writing to the wake-up socket
250        try:

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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