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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// Copyright (c) 2021-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#ifndef BITCOIN_ADDRMAN_IMPL_H
6#define BITCOIN_ADDRMAN_IMPL_H
7
8#include <logging/timer.h>
9#include <netaddress.h>
10#include <protocol.h>
11#include <serialize.h>
12#include <sync.h>
13#include <uint256.h>
14#include <util/log.h>
15#include <util/time.h>
16
17#include <cstdint>
18#include <optional>
19#include <set>
20#include <unordered_map>
21#include <unordered_set>
22#include <utility>
23#include <vector>
24
25/** Total number of buckets for tried addresses */
26inline constexpr int32_t ADDRMAN_TRIED_BUCKET_COUNT_LOG2{8};
27inline constexpr int ADDRMAN_TRIED_BUCKET_COUNT{1 << ADDRMAN_TRIED_BUCKET_COUNT_LOG2};
28/** Total number of buckets for new addresses */
29inline constexpr int32_t ADDRMAN_NEW_BUCKET_COUNT_LOG2{10};
30inline constexpr int ADDRMAN_NEW_BUCKET_COUNT{1 << ADDRMAN_NEW_BUCKET_COUNT_LOG2};
31/** Maximum allowed number of entries in buckets for new and tried addresses */
32inline constexpr int32_t ADDRMAN_BUCKET_SIZE_LOG2{6};
33inline constexpr int ADDRMAN_BUCKET_SIZE{1 << ADDRMAN_BUCKET_SIZE_LOG2};
34
35/**
36 * User-defined type for the internally used nIds
37 * This used to be int, making it feasible for attackers to cause an overflow,
38 * see https://bitcoincore.org/en/2024/07/31/disclose-addrman-int-overflow/
39 */
40using nid_type = int64_t;
41
42/**
43 * Extended statistics about a CAddress
44 */
45class AddrInfo : public CAddress
46{
47public:
48    //! last try whatsoever by us (memory only)
49    NodeSeconds m_last_try{0s};
50
51    //! last counted attempt (memory only)
52    NodeSeconds m_last_count_attempt{0s};
53
54    //! where knowledge about this address first came from
55    CNetAddr source;
56
57    //! last successful connection by us
58    NodeSeconds m_last_success{0s};
59
60    //! connection attempts since last successful attempt
61    int nAttempts{0};
62
63    //! reference count in new sets (memory only)
64    int nRefCount{0};
65
66    //! in tried set? (memory only)
67    bool fInTried{false};
68
69    //! position in vRandom
70    mutable int nRandomPos{-1};
71
72    SERIALIZE_METHODS(AddrInfo, obj)
73    {
74        READWRITE(AsBase<CAddress>(obj), obj.source, Using<ChronoFormatter<int64_t>>(obj.m_last_success), obj.nAttempts);
75    }
76
77    AddrInfo(const CAddress &addrIn, const CNetAddr &addrSource) : CAddress(addrIn), source(addrSource)
78    {
79    }
80
81    AddrInfo() : CAddress(), source()
82    {
83    }
84
85    //! Calculate in which "tried" bucket this entry belongs
86    int GetTriedBucket(const uint256& nKey, const NetGroupManager& netgroupman) const;
87
88    //! Calculate in which "new" bucket this entry belongs, given a certain source
89    int GetNewBucket(const uint256& nKey, const CNetAddr& src, const NetGroupManager& netgroupman) const;
90
91    //! Calculate in which "new" bucket this entry belongs, using its default source
92    int GetNewBucket(const uint256& nKey, const NetGroupManager& netgroupman) const
93    {
94        return GetNewBucket(nKey, source, netgroupman);
95    }
96
97    //! Calculate in which position of a bucket to store this entry.
98    int GetBucketPosition(const uint256 &nKey, bool fNew, int bucket) const;
99
100    //! Determine whether the statistics about this entry are bad enough so that it can just be deleted
101    bool IsTerrible(NodeSeconds now = Now<NodeSeconds>()) const;
102
103    //! Calculate the relative chance this entry should be given when selecting nodes to connect to
104    double GetChance(NodeSeconds now = Now<NodeSeconds>()) const;
105};
106
107class AddrManImpl
108{
109public:
110    AddrManImpl(const NetGroupManager& netgroupman, bool deterministic, int32_t consistency_check_ratio);
111
112    ~AddrManImpl();
113
114    template <typename Stream>
115    void Serialize(Stream& s_) const EXCLUSIVE_LOCKS_REQUIRED(!cs);
116
117    template <typename Stream>
118    void Unserialize(Stream& s_) EXCLUSIVE_LOCKS_REQUIRED(!cs);
119
120    size_t Size(std::optional<Network> net, std::optional<bool> in_new) const EXCLUSIVE_LOCKS_REQUIRED(!cs);
121
122    bool Add(const std::vector<CAddress>& vAddr, const CNetAddr& source, std::chrono::seconds time_penalty)
123        EXCLUSIVE_LOCKS_REQUIRED(!cs);
124
125    bool Good(const CService& addr, NodeSeconds time)
126        EXCLUSIVE_LOCKS_REQUIRED(!cs);
127
128    void Attempt(const CService& addr, bool fCountFailure, NodeSeconds time)
129        EXCLUSIVE_LOCKS_REQUIRED(!cs);
130
131    void ResolveCollisions() EXCLUSIVE_LOCKS_REQUIRED(!cs);
132
133    std::pair<CAddress, NodeSeconds> SelectTriedCollision() EXCLUSIVE_LOCKS_REQUIRED(!cs);
134
135    std::pair<CAddress, NodeSeconds> Select(bool new_only, const std::unordered_set<Network>& networks) const
136        EXCLUSIVE_LOCKS_REQUIRED(!cs);
137
138    std::vector<CAddress> GetAddr(size_t max_addresses, size_t max_pct, std::optional<Network> network, bool filtered = true) const
139        EXCLUSIVE_LOCKS_REQUIRED(!cs);
140
141    std::vector<std::pair<AddrInfo, AddressPosition>> GetEntries(bool from_tried) const
142        EXCLUSIVE_LOCKS_REQUIRED(!cs);
143
144    void Connected(const CService& addr, NodeSeconds time)
145        EXCLUSIVE_LOCKS_REQUIRED(!cs);
146
147    void SetServices(const CService& addr, ServiceFlags nServices)
148        EXCLUSIVE_LOCKS_REQUIRED(!cs);
149
150    std::optional<AddressPosition> FindAddressEntry(const CAddress& addr)
151        EXCLUSIVE_LOCKS_REQUIRED(!cs);
152
153    friend class AddrManDeterministic;
154
155private:
156    //! A mutex to protect the inner data structures.
157    mutable Mutex cs;
158
159    //! Source of random numbers for randomization in inner loops
160    mutable FastRandomContext insecure_rand GUARDED_BY(cs);
161
162    //! secret key to randomize bucket select with
163    uint256 nKey;
164
165    //! Serialization versions.
166    enum Format : uint8_t {
167        V0_HISTORICAL = 0,    //!< historic format, before commit e6b343d88
168        V1_DETERMINISTIC = 1, //!< for pre-asmap files
169        V2_ASMAP = 2,         //!< for files including asmap version
170        V3_BIP155 = 3,        //!< same as V2_ASMAP plus addresses are in BIP155 format
171        V4_MULTIPORT = 4,     //!< adds support for multiple ports per IP
172    };
173
174    //! The maximum format this software knows it can unserialize. Also, we always serialize
175    //! in this format.
176    //! The format (first byte in the serialized stream) can be higher than this and
177    //! still this software may be able to unserialize the file - if the second byte
178    //! (see `lowest_compatible` in `Unserialize()`) is less or equal to this.
179    static constexpr Format FILE_FORMAT = Format::V4_MULTIPORT;
180
181    //! The initial value of a field that is incremented every time an incompatible format
182    //! change is made (such that old software versions would not be able to parse and
183    //! understand the new file format). This is 32 because we overtook the "key size"
184    //! field which was 32 historically.
185    //! @note Don't increment this. Increment `lowest_compatible` in `Serialize()` instead.
186    static constexpr uint8_t INCOMPATIBILITY_BASE = 32;
187
188    //! last used nId
189    nid_type nIdCount GUARDED_BY(cs){0};
190
191    //! table with information about all nIds
192    std::unordered_map<nid_type, AddrInfo> mapInfo GUARDED_BY(cs);
193
194    //! find an nId based on its network address and port.
195    std::unordered_map<CService, nid_type, CServiceHash> mapAddr GUARDED_BY(cs);
196
197    //! randomly-ordered vector of all nIds
198    //! This is mutable because it is unobservable outside the class, so any
199    //! changes to it (even in const methods) are also unobservable.
200    mutable std::vector<nid_type> vRandom GUARDED_BY(cs);
201
202    // number of "tried" entries
203    int nTried GUARDED_BY(cs){0};
204
205    //! list of "tried" buckets
206    nid_type vvTried[ADDRMAN_TRIED_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE] GUARDED_BY(cs);
207
208    //! number of (unique) "new" entries
209    int nNew GUARDED_BY(cs){0};
210
211    //! list of "new" buckets
212    nid_type vvNew[ADDRMAN_NEW_BUCKET_COUNT][ADDRMAN_BUCKET_SIZE] GUARDED_BY(cs);
213
214    //! last time Good was called (memory only). Initially set to 1 so that "never" is strictly worse.
215    NodeSeconds m_last_good GUARDED_BY(cs){1s};
216
217    //! Holds addrs inserted into tried table that collide with existing entries. Test-before-evict discipline used to resolve these collisions.
218    std::set<nid_type> m_tried_collisions;
219
220    /** Perform consistency checks every m_consistency_check_ratio operations (if non-zero). */
221    const int32_t m_consistency_check_ratio;
222
223    /** Reference to the netgroup manager. netgroupman must be constructed before addrman and destructed after. */
224    const NetGroupManager& m_netgroupman;
225
226    struct NewTriedCount {
227        size_t n_new;
228        size_t n_tried;
229    };
230
231    /** Number of entries in addrman per network and new/tried table. */
232    std::unordered_map<Network, NewTriedCount> m_network_counts GUARDED_BY(cs);
233
234    //! Find an entry.
235    AddrInfo* Find(const CService& addr, nid_type* pnId = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs);
236
237    //! Create a new entry and add it to the internal data structures mapInfo, mapAddr and vRandom.
238    AddrInfo* Create(const CAddress& addr, const CNetAddr& addrSource, nid_type* pnId = nullptr) EXCLUSIVE_LOCKS_REQUIRED(cs);
239
240    //! Swap two elements in vRandom.
241    void SwapRandom(unsigned int nRandomPos1, unsigned int nRandomPos2) const EXCLUSIVE_LOCKS_REQUIRED(cs);
242
243    //! Delete an entry. It must not be in tried, and have refcount 0.
244    void Delete(nid_type nId) EXCLUSIVE_LOCKS_REQUIRED(cs);
245
246    //! Clear a position in a "new" table. This is the only place where entries are actually deleted.
247    void ClearNew(int nUBucket, int nUBucketPos) EXCLUSIVE_LOCKS_REQUIRED(cs);
248
249    //! Move an entry from the "new" table(s) to the "tried" table
250    void MakeTried(AddrInfo& info, nid_type nId) EXCLUSIVE_LOCKS_REQUIRED(cs);

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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