Bitcoin Core  26.99.0
P2P Digital Currency
protocol.h
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1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2022 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 
6 #ifndef BITCOIN_PROTOCOL_H
7 #define BITCOIN_PROTOCOL_H
8 
9 #include <kernel/messagestartchars.h> // IWYU pragma: export
10 #include <netaddress.h>
11 #include <primitives/transaction.h>
12 #include <serialize.h>
13 #include <streams.h>
14 #include <uint256.h>
15 #include <util/time.h>
16 
17 #include <array>
18 #include <cstdint>
19 #include <limits>
20 #include <string>
21 
29 {
30 public:
31  static constexpr size_t COMMAND_SIZE = 12;
32  static constexpr size_t MESSAGE_SIZE_SIZE = 4;
33  static constexpr size_t CHECKSUM_SIZE = 4;
34  static constexpr size_t MESSAGE_SIZE_OFFSET = std::tuple_size_v<MessageStartChars> + COMMAND_SIZE;
36  static constexpr size_t HEADER_SIZE = std::tuple_size_v<MessageStartChars> + COMMAND_SIZE + MESSAGE_SIZE_SIZE + CHECKSUM_SIZE;
37 
38  explicit CMessageHeader() = default;
39 
43  CMessageHeader(const MessageStartChars& pchMessageStartIn, const char* pszCommand, unsigned int nMessageSizeIn);
44 
45  std::string GetCommand() const;
46  bool IsCommandValid() const;
47 
48  SERIALIZE_METHODS(CMessageHeader, obj) { READWRITE(obj.pchMessageStart, obj.pchCommand, obj.nMessageSize, obj.pchChecksum); }
49 
52  uint32_t nMessageSize{std::numeric_limits<uint32_t>::max()};
54 };
55 
60 namespace NetMsgType {
61 
66 extern const char* VERSION;
71 extern const char* VERACK;
76 extern const char* ADDR;
82 extern const char *ADDRV2;
88 extern const char *SENDADDRV2;
93 extern const char* INV;
97 extern const char* GETDATA;
103 extern const char* MERKLEBLOCK;
108 extern const char* GETBLOCKS;
114 extern const char* GETHEADERS;
118 extern const char* TX;
124 extern const char* HEADERS;
128 extern const char* BLOCK;
133 extern const char* GETADDR;
140 extern const char* MEMPOOL;
145 extern const char* PING;
151 extern const char* PONG;
157 extern const char* NOTFOUND;
165 extern const char* FILTERLOAD;
173 extern const char* FILTERADD;
181 extern const char* FILTERCLEAR;
187 extern const char* SENDHEADERS;
193 extern const char* FEEFILTER;
201 extern const char* SENDCMPCT;
207 extern const char* CMPCTBLOCK;
213 extern const char* GETBLOCKTXN;
219 extern const char* BLOCKTXN;
225 extern const char* GETCFILTERS;
230 extern const char* CFILTER;
238 extern const char* GETCFHEADERS;
243 extern const char* CFHEADERS;
250 extern const char* GETCFCHECKPT;
255 extern const char* CFCHECKPT;
261 extern const char* WTXIDRELAY;
267 extern const char* SENDTXRCNCL;
268 }; // namespace NetMsgType
269 
270 /* Get a vector of all valid message types (see above) */
271 const std::vector<std::string>& getAllNetMessageTypes();
272 
274 enum ServiceFlags : uint64_t {
275  // NOTE: When adding here, be sure to update serviceFlagToStr too
276  // Nothing
278  // NODE_NETWORK means that the node is capable of serving the complete block chain. It is currently
279  // set by all Bitcoin Core non pruned nodes, and is unset by SPV clients or other light clients.
280  NODE_NETWORK = (1 << 0),
281  // NODE_BLOOM means the node is capable and willing to handle bloom-filtered connections.
282  NODE_BLOOM = (1 << 2),
283  // NODE_WITNESS indicates that a node can be asked for blocks and transactions including
284  // witness data.
285  NODE_WITNESS = (1 << 3),
286  // NODE_COMPACT_FILTERS means the node will service basic block filter requests.
287  // See BIP157 and BIP158 for details on how this is implemented.
289  // NODE_NETWORK_LIMITED means the same as NODE_NETWORK with the limitation of only
290  // serving the last 288 (2 day) blocks
291  // See BIP159 for details on how this is implemented.
292  NODE_NETWORK_LIMITED = (1 << 10),
293 
294  // NODE_P2P_V2 means the node supports BIP324 transport
295  NODE_P2P_V2 = (1 << 11),
296 
297  // Bits 24-31 are reserved for temporary experiments. Just pick a bit that
298  // isn't getting used, or one not being used much, and notify the
299  // bitcoin-development mailing list. Remember that service bits are just
300  // unauthenticated advertisements, so your code must be robust against
301  // collisions and other cases where nodes may be advertising a service they
302  // do not actually support. Other service bits should be allocated via the
303  // BIP process.
304 };
305 
311 std::vector<std::string> serviceFlagsToStr(uint64_t flags);
312 
320 
325 static inline bool MayHaveUsefulAddressDB(ServiceFlags services)
326 {
327  return (services & NODE_NETWORK) || (services & NODE_NETWORK_LIMITED);
328 }
329 
331 class CAddress : public CService
332 {
333  static constexpr std::chrono::seconds TIME_INIT{100000000};
334 
351  static constexpr uint32_t DISK_VERSION_INIT{220000};
352  static constexpr uint32_t DISK_VERSION_IGNORE_MASK{0b00000000'00000111'11111111'11111111};
356  static constexpr uint32_t DISK_VERSION_ADDRV2{1 << 29};
357  static_assert((DISK_VERSION_INIT & ~DISK_VERSION_IGNORE_MASK) == 0, "DISK_VERSION_INIT must be covered by DISK_VERSION_IGNORE_MASK");
358  static_assert((DISK_VERSION_ADDRV2 & DISK_VERSION_IGNORE_MASK) == 0, "DISK_VERSION_ADDRV2 must not be covered by DISK_VERSION_IGNORE_MASK");
359 
360 public:
361  CAddress() : CService{} {};
362  CAddress(CService ipIn, ServiceFlags nServicesIn) : CService{ipIn}, nServices{nServicesIn} {};
363  CAddress(CService ipIn, ServiceFlags nServicesIn, NodeSeconds time) : CService{ipIn}, nTime{time}, nServices{nServicesIn} {};
364 
365  enum class Format {
366  Disk,
367  Network,
368  };
370  const Format fmt;
372  };
377 
379  {
380  bool use_v2;
381  if (params.fmt == Format::Disk) {
382  // In the disk serialization format, the encoding (v1 or v2) is determined by a flag version
383  // that's part of the serialization itself. ADDRV2_FORMAT in the stream version only determines
384  // whether V2 is chosen/permitted at all.
385  uint32_t stored_format_version = DISK_VERSION_INIT;
386  if (params.enc == Encoding::V2) stored_format_version |= DISK_VERSION_ADDRV2;
387  READWRITE(stored_format_version);
388  stored_format_version &= ~DISK_VERSION_IGNORE_MASK; // ignore low bits
389  if (stored_format_version == 0) {
390  use_v2 = false;
391  } else if (stored_format_version == DISK_VERSION_ADDRV2 && params.enc == Encoding::V2) {
392  // Only support v2 deserialization if V2 is set.
393  use_v2 = true;
394  } else {
395  throw std::ios_base::failure("Unsupported CAddress disk format version");
396  }
397  } else {
398  assert(params.fmt == Format::Network);
399  // In the network serialization format, the encoding (v1 or v2) is determined directly by
400  // the value of enc in the stream params, as no explicitly encoded version
401  // exists in the stream.
402  use_v2 = params.enc == Encoding::V2;
403  }
404 
406  // nServices is serialized as CompactSize in V2; as uint64_t in V1.
407  if (use_v2) {
408  uint64_t services_tmp;
409  SER_WRITE(obj, services_tmp = obj.nServices);
411  SER_READ(obj, obj.nServices = static_cast<ServiceFlags>(services_tmp));
412  } else {
413  READWRITE(Using<CustomUintFormatter<8>>(obj.nServices));
414  }
415  // Invoke V1/V2 serializer for CService parent object.
416  const auto ser_params{use_v2 ? CNetAddr::V2 : CNetAddr::V1};
417  READWRITE(ser_params(AsBase<CService>(obj)));
418  }
419 
424 
425  friend bool operator==(const CAddress& a, const CAddress& b)
426  {
427  return a.nTime == b.nTime &&
428  a.nServices == b.nServices &&
429  static_cast<const CService&>(a) == static_cast<const CService&>(b);
430  }
431 };
432 
434 const uint32_t MSG_WITNESS_FLAG = 1 << 30;
435 const uint32_t MSG_TYPE_MASK = 0xffffffff >> 2;
436 
441 enum GetDataMsg : uint32_t {
443  MSG_TX = 1,
445  MSG_WTX = 5,
446  // The following can only occur in getdata. Invs always use TX/WTX or BLOCK.
451  // MSG_FILTERED_WITNESS_BLOCK is defined in BIP144 as reserved for future
452  // use and remains unused.
453  // MSG_FILTERED_WITNESS_BLOCK = MSG_FILTERED_BLOCK | MSG_WITNESS_FLAG,
454 };
455 
457 class CInv
458 {
459 public:
460  CInv();
461  CInv(uint32_t typeIn, const uint256& hashIn);
462 
463  SERIALIZE_METHODS(CInv, obj) { READWRITE(obj.type, obj.hash); }
464 
465  friend bool operator<(const CInv& a, const CInv& b);
466 
467  std::string GetCommand() const;
468  std::string ToString() const;
469 
470  // Single-message helper methods
471  bool IsMsgTx() const { return type == MSG_TX; }
472  bool IsMsgBlk() const { return type == MSG_BLOCK; }
473  bool IsMsgWtx() const { return type == MSG_WTX; }
474  bool IsMsgFilteredBlk() const { return type == MSG_FILTERED_BLOCK; }
475  bool IsMsgCmpctBlk() const { return type == MSG_CMPCT_BLOCK; }
476  bool IsMsgWitnessBlk() const { return type == MSG_WITNESS_BLOCK; }
477 
478  // Combined-message helper methods
479  bool IsGenTxMsg() const
480  {
481  return type == MSG_TX || type == MSG_WTX || type == MSG_WITNESS_TX;
482  }
483  bool IsGenBlkMsg() const
484  {
486  }
487 
488  uint32_t type;
490 };
491 
493 GenTxid ToGenTxid(const CInv& inv);
494 
495 #endif // BITCOIN_PROTOCOL_H
int flags
Definition: bitcoin-tx.cpp:530
A CService with information about it as peer.
Definition: protocol.h:332
static constexpr uint32_t DISK_VERSION_IGNORE_MASK
Definition: protocol.h:352
CAddress(CService ipIn, ServiceFlags nServicesIn, NodeSeconds time)
Definition: protocol.h:363
ServiceFlags nServices
Serialized as uint64_t in V1, and as CompactSize in V2.
Definition: protocol.h:423
static constexpr SerParams V1_NETWORK
Definition: protocol.h:373
NodeSeconds nTime
Always included in serialization. The behavior is unspecified if the value is not representable as ui...
Definition: protocol.h:421
static constexpr uint32_t DISK_VERSION_INIT
Historically, CAddress disk serialization stored the CLIENT_VERSION, optionally OR'ed with the ADDRV2...
Definition: protocol.h:351
static constexpr SerParams V2_NETWORK
Definition: protocol.h:374
CAddress()
Definition: protocol.h:361
friend bool operator==(const CAddress &a, const CAddress &b)
Definition: protocol.h:425
static constexpr SerParams V1_DISK
Definition: protocol.h:375
SERIALIZE_METHODS_PARAMS(CAddress, obj, SerParams, params)
Definition: protocol.h:378
CAddress(CService ipIn, ServiceFlags nServicesIn)
Definition: protocol.h:362
static constexpr std::chrono::seconds TIME_INIT
Definition: protocol.h:333
static constexpr uint32_t DISK_VERSION_ADDRV2
The version number written in disk serialized addresses to indicate V2 serializations.
Definition: protocol.h:356
static constexpr SerParams V2_DISK
Definition: protocol.h:376
inv message data
Definition: protocol.h:458
bool IsMsgCmpctBlk() const
Definition: protocol.h:475
friend bool operator<(const CInv &a, const CInv &b)
Definition: protocol.cpp:134
bool IsMsgBlk() const
Definition: protocol.h:472
std::string ToString() const
Definition: protocol.cpp:158
std::string GetCommand() const
Definition: protocol.cpp:139
bool IsMsgWtx() const
Definition: protocol.h:473
CInv()
Definition: protocol.cpp:126
uint32_t type
Definition: protocol.h:488
bool IsGenTxMsg() const
Definition: protocol.h:479
bool IsMsgTx() const
Definition: protocol.h:471
bool IsMsgFilteredBlk() const
Definition: protocol.h:474
uint256 hash
Definition: protocol.h:489
SERIALIZE_METHODS(CInv, obj)
Definition: protocol.h:463
bool IsGenBlkMsg() const
Definition: protocol.h:483
bool IsMsgWitnessBlk() const
Definition: protocol.h:476
Message header.
Definition: protocol.h:29
static constexpr size_t MESSAGE_SIZE_OFFSET
Definition: protocol.h:34
static constexpr size_t CHECKSUM_OFFSET
Definition: protocol.h:35
static constexpr size_t CHECKSUM_SIZE
Definition: protocol.h:33
CMessageHeader()=default
MessageStartChars pchMessageStart
Definition: protocol.h:50
static constexpr size_t MESSAGE_SIZE_SIZE
Definition: protocol.h:32
char pchCommand[COMMAND_SIZE]
Definition: protocol.h:51
static constexpr size_t HEADER_SIZE
Definition: protocol.h:36
uint8_t pchChecksum[CHECKSUM_SIZE]
Definition: protocol.h:53
std::string GetCommand() const
Definition: protocol.cpp:102
SERIALIZE_METHODS(CMessageHeader, obj)
Definition: protocol.h:48
static constexpr size_t COMMAND_SIZE
Definition: protocol.h:31
uint32_t nMessageSize
Definition: protocol.h:52
bool IsCommandValid() const
Definition: protocol.cpp:107
static constexpr SerParams V1
Definition: netaddress.h:231
@ V2
BIP155 encoding.
static constexpr SerParams V2
Definition: netaddress.h:232
A combination of a network address (CNetAddr) and a (TCP) port.
Definition: netaddress.h:531
A generic txid reference (txid or wtxid).
Definition: transaction.h:428
256-bit opaque blob.
Definition: uint256.h:106
std::array< uint8_t, 4 > MessageStartChars
Bitcoin protocol message types.
Definition: protocol.cpp:12
const char * FILTERLOAD
The filterload message tells the receiving peer to filter all relayed transactions and requested merk...
Definition: protocol.cpp:31
const char * CFHEADERS
cfheaders is a response to a getcfheaders request containing a filter header and a vector of filter h...
Definition: protocol.cpp:43
const char * CFILTER
cfilter is a response to a getcfilters request containing a single compact filter.
Definition: protocol.cpp:41
const char * BLOCK
The block message transmits a single serialized block.
Definition: protocol.cpp:25
const char * FILTERCLEAR
The filterclear message tells the receiving peer to remove a previously-set bloom filter.
Definition: protocol.cpp:33
const char * HEADERS
The headers message sends one or more block headers to a node which previously requested certain head...
Definition: protocol.cpp:24
const char * ADDRV2
The addrv2 message relays connection information for peers on the network just like the addr message,...
Definition: protocol.cpp:16
const char * SENDHEADERS
Indicates that a node prefers to receive new block announcements via a "headers" message rather than ...
Definition: protocol.cpp:34
const char * PONG
The pong message replies to a ping message, proving to the pinging node that the ponging node is stil...
Definition: protocol.cpp:29
const char * SENDCMPCT
Contains a 1-byte bool and 8-byte LE version number.
Definition: protocol.cpp:36
const char * GETADDR
The getaddr message requests an addr message from the receiving node, preferably one with lots of IP ...
Definition: protocol.cpp:26
const char * GETCFCHECKPT
getcfcheckpt requests evenly spaced compact filter headers, enabling parallelized download and valida...
Definition: protocol.cpp:44
const char * NOTFOUND
The notfound message is a reply to a getdata message which requested an object the receiving node doe...
Definition: protocol.cpp:30
const char * CMPCTBLOCK
Contains a CBlockHeaderAndShortTxIDs object - providing a header and list of "short txids".
Definition: protocol.cpp:37
const char * SENDTXRCNCL
Contains a 4-byte version number and an 8-byte salt.
Definition: protocol.cpp:47
const char * MEMPOOL
The mempool message requests the TXIDs of transactions that the receiving node has verified as valid ...
Definition: protocol.cpp:27
const char * GETCFILTERS
getcfilters requests compact filters for a range of blocks.
Definition: protocol.cpp:40
const char * TX
The tx message transmits a single transaction.
Definition: protocol.cpp:23
const char * FILTERADD
The filteradd message tells the receiving peer to add a single element to a previously-set bloom filt...
Definition: protocol.cpp:32
const char * ADDR
The addr (IP address) message relays connection information for peers on the network.
Definition: protocol.cpp:15
const char * VERSION
The version message provides information about the transmitting node to the receiving node at the beg...
Definition: protocol.cpp:13
const char * GETBLOCKS
The getblocks message requests an inv message that provides block header hashes starting from a parti...
Definition: protocol.cpp:21
const char * FEEFILTER
The feefilter message tells the receiving peer not to inv us any txs which do not meet the specified ...
Definition: protocol.cpp:35
const char * GETHEADERS
The getheaders message requests a headers message that provides block headers starting from a particu...
Definition: protocol.cpp:22
const char * GETDATA
The getdata message requests one or more data objects from another node.
Definition: protocol.cpp:19
const char * VERACK
The verack message acknowledges a previously-received version message, informing the connecting node ...
Definition: protocol.cpp:14
const char * BLOCKTXN
Contains a BlockTransactions.
Definition: protocol.cpp:39
const char * GETCFHEADERS
getcfheaders requests a compact filter header and the filter hashes for a range of blocks,...
Definition: protocol.cpp:42
const char * SENDADDRV2
The sendaddrv2 message signals support for receiving ADDRV2 messages (BIP155).
Definition: protocol.cpp:17
const char * WTXIDRELAY
Indicates that a node prefers to relay transactions via wtxid, rather than txid.
Definition: protocol.cpp:46
const char * PING
The ping message is sent periodically to help confirm that the receiving peer is still connected.
Definition: protocol.cpp:28
const char * MERKLEBLOCK
The merkleblock message is a reply to a getdata message which requested a block using the inventory t...
Definition: protocol.cpp:20
const char * CFCHECKPT
cfcheckpt is a response to a getcfcheckpt request containing a vector of evenly spaced filter headers...
Definition: protocol.cpp:45
const char * GETBLOCKTXN
Contains a BlockTransactionsRequest Peer should respond with "blocktxn" message.
Definition: protocol.cpp:38
const char * INV
The inv message (inventory message) transmits one or more inventories of objects known to the transmi...
Definition: protocol.cpp:18
GenTxid ToGenTxid(const CInv &inv)
Convert a TX/WITNESS_TX/WTX CInv to a GenTxid.
Definition: protocol.cpp:207
const std::vector< std::string > & getAllNetMessageTypes()
Definition: protocol.cpp:167
const uint32_t MSG_WITNESS_FLAG
getdata message type flags
Definition: protocol.h:434
const uint32_t MSG_TYPE_MASK
Definition: protocol.h:435
std::vector< std::string > serviceFlagsToStr(uint64_t flags)
Convert service flags (a bitmask of NODE_*) to human readable strings.
Definition: protocol.cpp:194
constexpr ServiceFlags SeedsServiceFlags()
State independent service flags.
Definition: protocol.h:319
GetDataMsg
getdata / inv message types.
Definition: protocol.h:441
@ MSG_TX
Definition: protocol.h:443
@ MSG_FILTERED_BLOCK
Defined in BIP37.
Definition: protocol.h:447
@ MSG_WTX
Defined in BIP 339.
Definition: protocol.h:445
@ MSG_BLOCK
Definition: protocol.h:444
@ UNDEFINED
Definition: protocol.h:442
@ MSG_CMPCT_BLOCK
Defined in BIP152.
Definition: protocol.h:448
@ MSG_WITNESS_BLOCK
Defined in BIP144.
Definition: protocol.h:449
@ MSG_WITNESS_TX
Defined in BIP144.
Definition: protocol.h:450
ServiceFlags
nServices flags
Definition: protocol.h:274
@ NODE_NONE
Definition: protocol.h:277
@ NODE_P2P_V2
Definition: protocol.h:295
@ NODE_WITNESS
Definition: protocol.h:285
@ NODE_NETWORK_LIMITED
Definition: protocol.h:292
@ NODE_BLOOM
Definition: protocol.h:282
@ NODE_NETWORK
Definition: protocol.h:280
@ NODE_COMPACT_FILTERS
Definition: protocol.h:288
static bool MayHaveUsefulAddressDB(ServiceFlags services)
Checks if a peer with the given service flags may be capable of having a robust address-storage DB.
Definition: protocol.h:325
#define SER_WRITE(obj, code)
Definition: serialize.h:161
static Wrapper< Formatter, T & > Using(T &&t)
Cause serialization/deserialization of an object to be done using a specified formatter class.
Definition: serialize.h:510
#define SER_READ(obj, code)
Definition: serialize.h:160
#define SER_PARAMS_OPFUNC
Helper macro for SerParams structs.
Definition: serialize.h:1175
#define READWRITE(...)
Definition: serialize.h:159
const Format fmt
Definition: protocol.h:370
Formatter for integers in CompactSize format.
Definition: serialize.h:579
Serialization wrapper class for custom integers and enums.
Definition: serialize.h:543
std::chrono::time_point< NodeClock, std::chrono::seconds > NodeSeconds
Definition: time.h:23
assert(!tx.IsCoinBase())