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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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6,240 bytes · SHA-256 b8c5bd857b18f271… · View upstream ↗

1// Copyright (c) 2011-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 <mapport.h>
6
7#include <clientversion.h>
8#include <common/netif.h>
9#include <common/pcp.h>
10#include <common/system.h>
11#include <net.h>
12#include <netaddress.h>
13#include <netbase.h>
14#include <random.h>
15#include <util/log.h>
16#include <util/thread.h>
17#include <util/threadinterrupt.h>
18
19#include <atomic>
20#include <cassert>
21#include <chrono>
22#include <functional>
23#include <string>
24#include <thread>
25
26static CThreadInterrupt g_mapport_interrupt;
27static std::thread g_mapport_thread;
28
29using namespace std::chrono_literals;
30static constexpr auto PORT_MAPPING_REANNOUNCE_PERIOD{20min};
31static constexpr auto PORT_MAPPING_RETRY_PERIOD{5min};
32
33static void ProcessPCP()
34{
35    // The same nonce is used for all mappings, this is allowed by the spec, and simplifies keeping track of them.
36    PCPMappingNonce pcp_nonce;
37    GetRandBytes(pcp_nonce);
38
39    bool ret = false;
40    bool no_resources = false;
41    const uint16_t private_port = GetListenPort();
42    // Multiply the reannounce period by two, as we'll try to renew approximately halfway.
43    const uint32_t requested_lifetime = std::chrono::seconds(PORT_MAPPING_REANNOUNCE_PERIOD * 2).count();
44    uint32_t actual_lifetime = 0;
45    std::chrono::milliseconds sleep_time;
46
47    // Local functor to handle result from PCP/NATPMP mapping.
48    auto handle_mapping = [&](std::variant<MappingResult, MappingError> &res) -> void {
49        if (MappingResult* mapping = std::get_if<MappingResult>(&res)) {
50            LogInfo("portmap: Added mapping %s", mapping->ToString());
51            AddLocal(mapping->external, LOCAL_MAPPED);
52            ret = true;
53            actual_lifetime = std::min(actual_lifetime, mapping->lifetime);
54        } else if (MappingError *err = std::get_if<MappingError>(&res)) {
55            // Detailed error will already have been logged internally in respective Portmap function.
56            if (*err == MappingError::NO_RESOURCES) {
57                no_resources = true;
58            }
59        }
60    };
61
62    do {
63        actual_lifetime = requested_lifetime;
64        no_resources = false; // Set to true if there was any "no resources" error.
65        ret = false; // Set to true if any mapping succeeds.
66
67        // IPv4
68        std::optional<CNetAddr> gateway4 = QueryDefaultGateway(NET_IPV4);
69        if (!gateway4) {
70            LogDebug(BCLog::NET, "portmap: Could not determine IPv4 default gateway\n");
71        } else {
72            LogDebug(BCLog::NET, "portmap: gateway [IPv4]: %s\n", gateway4->ToStringAddr());
73
74            // Open a port mapping on whatever local address we have toward the gateway.
75            struct in_addr inaddr_any;
76            inaddr_any.s_addr = htonl(INADDR_ANY);
77            auto res = PCPRequestPortMap(pcp_nonce, *gateway4, CNetAddr(inaddr_any), private_port, requested_lifetime, g_mapport_interrupt);
78            MappingError* pcp_err = std::get_if<MappingError>(&res);
79            if (pcp_err && *pcp_err == MappingError::UNSUPP_VERSION) {
80                LogDebug(BCLog::NET, "portmap: Got unsupported PCP version response, falling back to NAT-PMP\n");
81                res = NATPMPRequestPortMap(*gateway4, private_port, requested_lifetime, g_mapport_interrupt);
82            }
83            handle_mapping(res);
84        }
85
86        // IPv6
87        std::optional<CNetAddr> gateway6 = QueryDefaultGateway(NET_IPV6);
88        if (!gateway6) {
89            LogDebug(BCLog::NET, "portmap: Could not determine IPv6 default gateway\n");
90        } else {
91            LogDebug(BCLog::NET, "portmap: gateway [IPv6]: %s\n", gateway6->ToStringAddr());
92
93            // Try to open pinholes for all routable local IPv6 addresses.
94            for (const auto &addr: GetLocalAddresses()) {
95                if (!addr.IsRoutable() || !addr.IsIPv6()) continue;
96                auto res = PCPRequestPortMap(pcp_nonce, *gateway6, addr, private_port, requested_lifetime, g_mapport_interrupt);
97                handle_mapping(res);
98            }
99        }
100
101        // Log message if we got NO_RESOURCES.
102        if (no_resources) {
103            LogWarning("portmap: At least one mapping failed because of a NO_RESOURCES error. This usually indicates that the port is already used on the router. If this is the only instance of bitcoin running on the network, this will resolve itself automatically. Otherwise, you might want to choose a different P2P port to prevent this conflict.\n");
104        }
105
106        // Sanity-check returned lifetime.
107        if (actual_lifetime < 30) {
108            LogWarning("portmap: Got impossibly short mapping lifetime of %d seconds\n", actual_lifetime);
109            return;
110        }
111        // RFC6887 11.2.1 recommends that clients send their first renewal packet at a time chosen with uniform random
112        // distribution in the range 1/2 to 5/8 of expiration time.
113        std::chrono::seconds sleep_time_min(actual_lifetime / 2);
114        std::chrono::seconds sleep_time_max(actual_lifetime * 5 / 8);
115        sleep_time = sleep_time_min + FastRandomContext().randrange<std::chrono::milliseconds>(sleep_time_max - sleep_time_min);
116    } while (ret && g_mapport_interrupt.sleep_for(sleep_time));
117
118    // We don't delete the mappings when the thread is interrupted because this would add additional complexity, so
119    // we rather just choose a fairly short expiry time.
120}
121
122/// \anchor mapport
123static void ThreadMapPort()
124{
125    do {
126        ProcessPCP();
127    } while (g_mapport_interrupt.sleep_for(PORT_MAPPING_RETRY_PERIOD));
128}
129
130void StartThreadMapPort()
131{
132    if (!g_mapport_thread.joinable()) {
133        assert(!g_mapport_interrupt);
134        g_mapport_thread = std::thread(&util::TraceThread, "mapport", &ThreadMapPort);
135    }
136}
137
138void StartMapPort(bool enable)
139{
140    if (enable) {
141        StartThreadMapPort();
142    } else {
143        InterruptMapPort();
144        StopMapPort();
145    }
146}
147
148void InterruptMapPort()
149{
150    if (g_mapport_thread.joinable()) {
151        g_mapport_interrupt();
152    }
153}
154
155void StopMapPort()
156{
157    if (g_mapport_thread.joinable()) {
158        g_mapport_thread.join();
159        g_mapport_interrupt.reset();
160    }
161}
162

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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