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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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1// Copyright (c) 2009-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_NETADDRESS_H
6#define BITCOIN_NETADDRESS_H
7
8#include <compat/compat.h>
9#include <crypto/siphash.h>
10#include <prevector.h>
11#include <random.h>
12#include <serialize.h>
13#include <tinyformat.h>
14#include <util/strencodings.h>
15#include <util/string.h>
16
17#include <array>
18#include <cstdint>
19#include <ios>
20#include <string>
21#include <string_view>
22#include <vector>
23
24/**
25 * A network type.
26 * @note An address may belong to more than one network, for example `10.0.0.1`
27 * belongs to both `NET_UNROUTABLE` and `NET_IPV4`.
28 * Keep these sequential starting from 0 and `NET_MAX` as the last entry.
29 * We have loops like `for (int i = 0; i < NET_MAX; ++i)` that expect to iterate
30 * over all enum values and also `GetExtNetwork()` "extends" this enum by
31 * introducing standalone constants starting from `NET_MAX`.
32 */
33enum Network {
34    /// Addresses from these networks are not publicly routable on the global Internet.
35    NET_UNROUTABLE = 0,
36
37    /// IPv4
38    NET_IPV4,
39
40    /// IPv6
41    NET_IPV6,
42
43    /// TOR (v2 or v3)
44    NET_ONION,
45
46    /// I2P
47    NET_I2P,
48
49    /// CJDNS
50    NET_CJDNS,
51
52    /// A set of addresses that represent the hash of a string or FQDN. We use
53    /// them in AddrMan to keep track of which DNS seeds were used.
54    NET_INTERNAL,
55
56    /// Dummy value to indicate the number of NET_* constants.
57    NET_MAX,
58};
59
60/// Prefix of an IPv6 address when it contains an embedded IPv4 address.
61/// Used when (un)serializing addresses in ADDRv1 format (pre-BIP155).
62inline constexpr std::array<uint8_t, 12> IPV4_IN_IPV6_PREFIX{
63    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF};
64
65/// Prefix of an IPv6 address when it contains an embedded TORv2 address.
66/// Used when (un)serializing addresses in ADDRv1 format (pre-BIP155).
67/// Such dummy IPv6 addresses are guaranteed to not be publicly routable as they
68/// fall under RFC4193's fc00::/7 subnet allocated to unique-local addresses.
69inline constexpr std::array<uint8_t, 6> TORV2_IN_IPV6_PREFIX{
70    0xFD, 0x87, 0xD8, 0x7E, 0xEB, 0x43};
71
72/// Prefix of an IPv6 address when it contains an embedded "internal" address.
73/// Used when (un)serializing addresses in ADDRv1 format (pre-BIP155).
74/// The prefix comes from 0xFD + SHA256("bitcoin")[0:5].
75/// Such dummy IPv6 addresses are guaranteed to not be publicly routable as they
76/// fall under RFC4193's fc00::/7 subnet allocated to unique-local addresses.
77inline constexpr std::array<uint8_t, 6> INTERNAL_IN_IPV6_PREFIX{
78    0xFD, 0x6B, 0x88, 0xC0, 0x87, 0x24 // 0xFD + sha256("bitcoin")[0:5].
79};
80
81/// All CJDNS addresses start with 0xFC. See
82/// https://github.com/cjdelisle/cjdns/blob/master/doc/Whitepaper.md#pulling-it-all-together
83inline constexpr uint8_t CJDNS_PREFIX{0xFC};
84
85/// Size of IPv4 address (in bytes).
86inline constexpr size_t ADDR_IPV4_SIZE = 4;
87
88/// Size of IPv6 address (in bytes).
89inline constexpr size_t ADDR_IPV6_SIZE = 16;
90
91/// Size of TORv3 address (in bytes). This is the length of just the address
92/// as used in BIP155, without the checksum and the version byte.
93inline constexpr size_t ADDR_TORV3_SIZE = 32;
94
95/// Size of I2P address (in bytes).
96inline constexpr size_t ADDR_I2P_SIZE = 32;
97
98/// Size of CJDNS address (in bytes).
99inline constexpr size_t ADDR_CJDNS_SIZE = 16;
100
101/// Size of "internal" (NET_INTERNAL) address (in bytes).
102inline constexpr size_t ADDR_INTERNAL_SIZE = 10;
103
104/// SAM 3.1 and earlier do not support specifying ports and force the port to 0.
105inline constexpr uint16_t I2P_SAM31_PORT{0};
106
107std::string OnionToString(std::span<const uint8_t> addr);
108
109/**
110 * Network address.
111 */
112class CNetAddr
113{
114protected:
115    /**
116     * Raw representation of the network address.
117     * In network byte order (big endian) for IPv4 and IPv6.
118     */
119    prevector<ADDR_IPV6_SIZE, uint8_t> m_addr{ADDR_IPV6_SIZE, 0x0};
120
121    /**
122     * Network to which this address belongs.
123     */
124    Network m_net{NET_IPV6};
125
126    /**
127     * Scope id if scoped/link-local IPV6 address.
128     * See https://tools.ietf.org/html/rfc4007
129     */
130    uint32_t m_scope_id{0};
131
132public:
133    CNetAddr();
134    explicit CNetAddr(const struct in_addr& ipv4Addr);
135    void SetIP(const CNetAddr& ip);
136
137    /**
138     * Set from a legacy IPv6 address.
139     * Legacy IPv6 address may be a normal IPv6 address, or another address
140     * (e.g. IPv4) disguised as IPv6. This encoding is used in the legacy
141     * `addr` encoding.
142     */
143    void SetLegacyIPv6(std::span<const uint8_t> ipv6);
144
145    bool SetInternal(const std::string& name);
146
147    /**
148     * Parse a Tor or I2P address and set this object to it.
149     * @param[in] addr Address to parse, for example
150     * pg6mmjiyjmcrsslvykfwnntlaru7p5svn6y2ymmju6nubxndf4pscryd.onion or
151     * ukeu3k5oycgaauneqgtnvselmt4yemvoilkln7jpvamvfx7dnkdq.b32.i2p.
152     * @returns Whether the operation was successful.
153     * @see CNetAddr::IsTor(), CNetAddr::IsI2P()
154     */
155    bool SetSpecial(std::string_view addr);
156
157    bool IsBindAny() const; // INADDR_ANY equivalent
158    [[nodiscard]] bool IsIPv4() const { return m_net == NET_IPV4; } // IPv4 mapped address (::FFFF:0:0/96, 0.0.0.0/0)
159    [[nodiscard]] bool IsIPv6() const { return m_net == NET_IPV6; } // IPv6 address (not mapped IPv4, not Tor)
160    bool IsRFC1918() const; // IPv4 private networks (10.0.0.0/8, 192.168.0.0/16, 172.16.0.0/12)
161    bool IsRFC2544() const; // IPv4 inter-network communications (198.18.0.0/15)
162    bool IsRFC6598() const; // IPv4 ISP-level NAT (100.64.0.0/10)
163    bool IsRFC5737() const; // IPv4 documentation addresses (192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24)
164    bool IsRFC3849() const; // IPv6 documentation address (2001:0DB8::/32)
165    bool IsRFC9637() const; // IPv6 documentation address (3FFF::/20)
166    bool IsRFC3927() const; // IPv4 autoconfig (169.254.0.0/16)
167    bool IsRFC3964() const; // IPv6 6to4 tunnelling (2002::/16)
168    bool IsRFC4193() const; // IPv6 unique local (FC00::/7)
169    bool IsRFC4380() const; // IPv6 Teredo tunnelling (2001::/32)
170    bool IsRFC4843() const; // IPv6 ORCHID (deprecated) (2001:10::/28)
171    bool IsRFC7343() const; // IPv6 ORCHIDv2 (2001:20::/28)
172    bool IsRFC4862() const; // IPv6 autoconfig (FE80::/64)
173    bool IsRFC6052() const; // IPv6 well-known prefix for IPv4-embedded address (64:FF9B::/96)
174    bool IsRFC6145() const; // IPv6 IPv4-translated address (::FFFF:0:0:0/96) (actually defined in RFC2765)
175    bool IsHeNet() const;   // IPv6 Hurricane Electric - https://he.net (2001:0470::/36)
176    [[nodiscard]] bool IsTor() const { return m_net == NET_ONION; }
177    [[nodiscard]] bool IsI2P() const { return m_net == NET_I2P; }
178    [[nodiscard]] bool IsCJDNS() const { return m_net == NET_CJDNS; }
179    [[nodiscard]] bool HasCJDNSPrefix() const { return m_addr[0] == CJDNS_PREFIX; }
180    bool IsLocal() const;
181    bool IsRoutable() const;
182    bool IsInternal() const;
183    bool IsValid() const;
184
185    /**
186     * Whether this object is a privacy network.
187     * TODO: consider adding IsCJDNS() here when more peers adopt CJDNS, see:
188     * https://github.com/bitcoin/bitcoin/pull/27411#issuecomment-1497176155
189     */
190    [[nodiscard]] bool IsPrivacyNet() const { return IsTor() || IsI2P(); }
191
192    /**
193     * Check if the current object can be serialized in pre-ADDRv2/BIP155 format.
194     */
195    bool IsAddrV1Compatible() const;
196
197    enum Network GetNetwork() const;
198    std::string ToStringAddr() const;
199    bool GetInAddr(struct in_addr* pipv4Addr) const;
200    Network GetNetClass() const;
201
202    //! For IPv4, mapped IPv4, SIIT translated IPv4, Teredo, 6to4 tunneled addresses, return the relevant IPv4 address as a uint32.
203    uint32_t GetLinkedIPv4() const;
204    //! Whether this address has a linked IPv4 address (see GetLinkedIPv4()).
205    bool HasLinkedIPv4() const;
206
207    std::vector<unsigned char> GetAddrBytes() const;
208    int GetReachabilityFrom(const CNetAddr& paddrPartner) const;
209
210    explicit CNetAddr(const struct in6_addr& pipv6Addr, uint32_t scope = 0);
211    bool GetIn6Addr(struct in6_addr* pipv6Addr) const;
212
213    friend bool operator==(const CNetAddr& a, const CNetAddr& b);
214    friend bool operator<(const CNetAddr& a, const CNetAddr& b);
215
216    /**
217     * Whether this address should be relayed to other peers even if we can't reach it ourselves.
218     */
219    bool IsRelayable() const
220    {
221        return IsIPv4() || IsIPv6() || IsTor() || IsI2P() || IsCJDNS();
222    }
223
224    enum class Encoding {
225        V1,
226        V2, //!< BIP155 encoding
227    };
228    struct SerParams {
229        const Encoding enc;
230        SER_PARAMS_OPFUNC
231    };
232    static constexpr SerParams V1{Encoding::V1};
233    static constexpr SerParams V2{Encoding::V2};
234
235    /**
236     * Serialize to a stream.
237     */
238    template <typename Stream>
239    void Serialize(Stream& s) const
240    {
241        if (s.template GetParams<SerParams>().enc == Encoding::V2) {
242            SerializeV2Stream(s);
243        } else {
244            SerializeV1Stream(s);
245        }
246    }
247
248    /**
249     * Unserialize from a stream.
250     */

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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