Bitcoin Core  0.20.99
P2P Digital Currency
protocol.h
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1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2019 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 __cplusplus
7 #error This header can only be compiled as C++.
8 #endif
9 
10 #ifndef BITCOIN_PROTOCOL_H
11 #define BITCOIN_PROTOCOL_H
12 
13 #include <netaddress.h>
14 #include <primitives/transaction.h>
15 #include <serialize.h>
16 #include <uint256.h>
17 #include <version.h>
18 
19 #include <stdint.h>
20 #include <string>
21 
29 {
30 public:
31  static constexpr size_t MESSAGE_START_SIZE = 4;
32  static constexpr size_t COMMAND_SIZE = 12;
33  static constexpr size_t MESSAGE_SIZE_SIZE = 4;
34  static constexpr size_t CHECKSUM_SIZE = 4;
35  static constexpr size_t MESSAGE_SIZE_OFFSET = MESSAGE_START_SIZE + COMMAND_SIZE;
36  static constexpr size_t CHECKSUM_OFFSET = MESSAGE_SIZE_OFFSET + MESSAGE_SIZE_SIZE;
37  static constexpr size_t HEADER_SIZE = MESSAGE_START_SIZE + COMMAND_SIZE + MESSAGE_SIZE_SIZE + CHECKSUM_SIZE;
38  typedef unsigned char MessageStartChars[MESSAGE_START_SIZE];
39 
40  explicit CMessageHeader(const MessageStartChars& pchMessageStartIn);
41 
45  CMessageHeader(const MessageStartChars& pchMessageStartIn, const char* pszCommand, unsigned int nMessageSizeIn);
46 
47  std::string GetCommand() const;
48  bool IsValid(const MessageStartChars& messageStart) const;
49 
50  SERIALIZE_METHODS(CMessageHeader, obj) { READWRITE(obj.pchMessageStart, obj.pchCommand, obj.nMessageSize, obj.pchChecksum); }
51 
54  uint32_t nMessageSize;
56 };
57 
62 namespace NetMsgType {
63 
68 extern const char* VERSION;
73 extern const char* VERACK;
78 extern const char* ADDR;
83 extern const char* INV;
87 extern const char* GETDATA;
93 extern const char* MERKLEBLOCK;
98 extern const char* GETBLOCKS;
104 extern const char* GETHEADERS;
108 extern const char* TX;
114 extern const char* HEADERS;
118 extern const char* BLOCK;
123 extern const char* GETADDR;
129 extern const char* MEMPOOL;
134 extern const char* PING;
140 extern const char* PONG;
146 extern const char* NOTFOUND;
154 extern const char* FILTERLOAD;
162 extern const char* FILTERADD;
170 extern const char* FILTERCLEAR;
176 extern const char* SENDHEADERS;
182 extern const char* FEEFILTER;
190 extern const char* SENDCMPCT;
196 extern const char* CMPCTBLOCK;
202 extern const char* GETBLOCKTXN;
208 extern const char* BLOCKTXN;
214 extern const char* GETCFILTERS;
219 extern const char* CFILTER;
227 extern const char* GETCFHEADERS;
232 extern const char* CFHEADERS;
239 extern const char* GETCFCHECKPT;
244 extern const char* CFCHECKPT;
250 extern const char* WTXIDRELAY;
251 }; // namespace NetMsgType
252 
253 /* Get a vector of all valid message types (see above) */
254 const std::vector<std::string>& getAllNetMessageTypes();
255 
257 enum ServiceFlags : uint64_t {
258  // NOTE: When adding here, be sure to update serviceFlagToStr too
259  // Nothing
261  // NODE_NETWORK means that the node is capable of serving the complete block chain. It is currently
262  // set by all Bitcoin Core non pruned nodes, and is unset by SPV clients or other light clients.
263  NODE_NETWORK = (1 << 0),
264  // NODE_GETUTXO means the node is capable of responding to the getutxo protocol request.
265  // Bitcoin Core does not support this but a patch set called Bitcoin XT does.
266  // See BIP 64 for details on how this is implemented.
267  NODE_GETUTXO = (1 << 1),
268  // NODE_BLOOM means the node is capable and willing to handle bloom-filtered connections.
269  // Bitcoin Core nodes used to support this by default, without advertising this bit,
270  // but no longer do as of protocol version 70011 (= NO_BLOOM_VERSION)
271  NODE_BLOOM = (1 << 2),
272  // NODE_WITNESS indicates that a node can be asked for blocks and transactions including
273  // witness data.
274  NODE_WITNESS = (1 << 3),
275  // NODE_COMPACT_FILTERS means the node will service basic block filter requests.
276  // See BIP157 and BIP158 for details on how this is implemented.
278  // NODE_NETWORK_LIMITED means the same as NODE_NETWORK with the limitation of only
279  // serving the last 288 (2 day) blocks
280  // See BIP159 for details on how this is implemented.
281  NODE_NETWORK_LIMITED = (1 << 10),
282 
283  // Bits 24-31 are reserved for temporary experiments. Just pick a bit that
284  // isn't getting used, or one not being used much, and notify the
285  // bitcoin-development mailing list. Remember that service bits are just
286  // unauthenticated advertisements, so your code must be robust against
287  // collisions and other cases where nodes may be advertising a service they
288  // do not actually support. Other service bits should be allocated via the
289  // BIP process.
290 };
291 
297 std::vector<std::string> serviceFlagsToStr(uint64_t flags);
298 
324 
326 void SetServiceFlagsIBDCache(bool status);
327 
333 static inline bool HasAllDesirableServiceFlags(ServiceFlags services)
334 {
335  return !(GetDesirableServiceFlags(services) & (~services));
336 }
337 
342 static inline bool MayHaveUsefulAddressDB(ServiceFlags services)
343 {
344  return (services & NODE_NETWORK) || (services & NODE_NETWORK_LIMITED);
345 }
346 
348 class CAddress : public CService
349 {
350  static constexpr uint32_t TIME_INIT{100000000};
351 
352 public:
353  CAddress() : CService{} {};
354  explicit CAddress(CService ipIn, ServiceFlags nServicesIn) : CService{ipIn}, nServices{nServicesIn} {};
355 
357  {
358  SER_READ(obj, obj.nTime = TIME_INIT);
359  int nVersion = s.GetVersion();
360  if (s.GetType() & SER_DISK) {
361  READWRITE(nVersion);
362  }
363  if ((s.GetType() & SER_DISK) ||
364  (nVersion != INIT_PROTO_VERSION && !(s.GetType() & SER_GETHASH))) {
365  // The only time we serialize a CAddress object without nTime is in
366  // the initial VERSION messages which contain two CAddress records.
367  // At that point, the serialization version is INIT_PROTO_VERSION.
368  // After the version handshake, serialization version is >=
369  // MIN_PEER_PROTO_VERSION and all ADDR messages are serialized with
370  // nTime.
371  READWRITE(obj.nTime);
372  }
373  READWRITE(Using<CustomUintFormatter<8>>(obj.nServices));
374  READWRITEAS(CService, obj);
375  }
376 
377  // disk and network only
378  uint32_t nTime{TIME_INIT};
379 
381 };
382 
384 const uint32_t MSG_WITNESS_FLAG = 1 << 30;
385 const uint32_t MSG_TYPE_MASK = 0xffffffff >> 2;
386 
391 enum GetDataMsg : uint32_t {
393  MSG_TX = 1,
395  MSG_WTX = 5,
396  // The following can only occur in getdata. Invs always use TX/WTX or BLOCK.
401  // MSG_FILTERED_WITNESS_BLOCK is defined in BIP144 as reserved for future
402  // use and remains unused.
403  // MSG_FILTERED_WITNESS_BLOCK = MSG_FILTERED_BLOCK | MSG_WITNESS_FLAG,
404 };
405 
407 class CInv
408 {
409 public:
410  CInv();
411  CInv(uint32_t typeIn, const uint256& hashIn);
412 
413  SERIALIZE_METHODS(CInv, obj) { READWRITE(obj.type, obj.hash); }
414 
415  friend bool operator<(const CInv& a, const CInv& b);
416 
417  std::string GetCommand() const;
418  std::string ToString() const;
419 
420  // Single-message helper methods
421  bool IsMsgTx() const { return type == MSG_TX; }
422  bool IsMsgBlk() const { return type == MSG_BLOCK; }
423  bool IsMsgWtx() const { return type == MSG_WTX; }
424  bool IsMsgFilteredBlk() const { return type == MSG_FILTERED_BLOCK; }
425  bool IsMsgCmpctBlk() const { return type == MSG_CMPCT_BLOCK; }
426  bool IsMsgWitnessBlk() const { return type == MSG_WITNESS_BLOCK; }
427 
428  // Combined-message helper methods
429  bool IsGenTxMsg() const
430  {
431  return type == MSG_TX || type == MSG_WTX || type == MSG_WITNESS_TX;
432  }
433  bool IsGenBlkMsg() const
434  {
435  return type == MSG_BLOCK || type == MSG_FILTERED_BLOCK || type == MSG_CMPCT_BLOCK || type == MSG_WITNESS_BLOCK;
436  }
437 
438  uint32_t type;
440 };
441 
443 GenTxid ToGenTxid(const CInv& inv);
444 
445 #endif // BITCOIN_PROTOCOL_H
const char * GETCFILTERS
getcfilters requests compact filters for a range of blocks.
Definition: protocol.cpp:39
bool IsMsgWtx() const
Definition: protocol.h:423
const char * PING
The ping message is sent periodically to help confirm that the receiving peer is still connected...
Definition: protocol.cpp:27
const char * FILTERLOAD
The filterload message tells the receiving peer to filter all relayed transactions and requested merk...
Definition: protocol.cpp:30
const char * MERKLEBLOCK
The merkleblock message is a reply to a getdata message which requested a block using the inventory t...
Definition: protocol.cpp:19
uint8_t pchChecksum[CHECKSUM_SIZE]
Definition: protocol.h:55
const char * BLOCKTXN
Contains a BlockTransactions.
Definition: protocol.cpp:38
bool IsMsgTx() const
Definition: protocol.h:421
ServiceFlags
nServices flags
Definition: protocol.h:257
static constexpr size_t MESSAGE_SIZE_SIZE
Definition: protocol.h:33
const std::vector< std::string > & getAllNetMessageTypes()
Definition: protocol.cpp:197
const char * GETADDR
The getaddr message requests an addr message from the receiving node, preferably one with lots of IP ...
Definition: protocol.cpp:25
bool IsMsgFilteredBlk() const
Definition: protocol.h:424
inv message data
Definition: protocol.h:407
const char * SENDCMPCT
Contains a 1-byte bool and 8-byte LE version number.
Definition: protocol.cpp:35
char pchCommand[COMMAND_SIZE]
Definition: protocol.h:53
bool IsMsgCmpctBlk() const
Definition: protocol.h:425
const char * CFHEADERS
cfheaders is a response to a getcfheaders request containing a filter header and a vector of filter h...
Definition: protocol.cpp:42
Defined in BIP152.
Definition: protocol.h:398
GenTxid ToGenTxid(const CInv &inv)
Convert a TX/WITNESS_TX/WTX CInv to a GenTxid.
Definition: protocol.cpp:242
CMessageHeader(const MessageStartChars &pchMessageStartIn)
Definition: protocol.cpp:87
SERIALIZE_METHODS(CAddress, obj)
Definition: protocol.h:356
const uint32_t MSG_WITNESS_FLAG
getdata message type flags
Definition: protocol.h:384
uint32_t nMessageSize
Definition: protocol.h:54
const char * CFILTER
cfilter is a response to a getcfilters request containing a single compact filter.
Definition: protocol.cpp:40
const uint32_t MSG_TYPE_MASK
Definition: protocol.h:385
std::string GetCommand() const
Definition: protocol.cpp:109
#define READWRITEAS(type, obj)
Definition: serialize.h:172
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:28
bool IsValid(const MessageStartChars &messageStart) const
Definition: protocol.cpp:114
const char * WTXIDRELAY
Indicates that a node prefers to relay transactions via wtxid, rather than txid.
Definition: protocol.cpp:45
const char * HEADERS
The headers message sends one or more block headers to a node which previously requested certain head...
Definition: protocol.cpp:23
static Wrapper< Formatter, T & > Using(T &&t)
Cause serialization/deserialization of an object to be done using a specified formatter class...
Definition: serialize.h:465
const char * GETCFCHECKPT
getcfcheckpt requests evenly spaced compact filter headers, enabling parallelized download and valida...
Definition: protocol.cpp:43
const char * INV
The inv message (inventory message) transmits one or more inventories of objects known to the transmi...
Definition: protocol.cpp:17
std::string ToString(const T &t)
Locale-independent version of std::to_string.
Definition: string.h:69
ServiceFlags GetDesirableServiceFlags(ServiceFlags services)
Gets the set of service flags which are "desirable" for a given peer.
Definition: protocol.cpp:145
bool IsGenBlkMsg() const
Definition: protocol.h:433
const char * GETHEADERS
The getheaders message requests a headers message that provides block headers starting from a particu...
Definition: protocol.cpp:21
static constexpr size_t COMMAND_SIZE
Definition: protocol.h:32
static bool HasAllDesirableServiceFlags(ServiceFlags services)
A shortcut for (services & GetDesirableServiceFlags(services)) == GetDesirableServiceFlags(services)...
Definition: protocol.h:333
Bitcoin protocol message types.
Definition: protocol.cpp:13
static const int INIT_PROTO_VERSION
initial proto version, to be increased after version/verack negotiation
Definition: version.h:15
A combination of a network address (CNetAddr) and a (TCP) port.
Definition: netaddress.h:308
Removed for block.
const char * SENDHEADERS
Indicates that a node prefers to receive new block announcements via a "headers" message rather than ...
Definition: protocol.cpp:33
bool IsGenTxMsg() const
Definition: protocol.h:429
A CService with information about it as peer.
Definition: protocol.h:348
uint256 hash
Definition: protocol.h:439
const char * ADDR
The addr (IP address) message relays connection information for peers on the network.
Definition: protocol.cpp:16
Defined in BIP144.
Definition: protocol.h:399
const char * FILTERCLEAR
The filterclear message tells the receiving peer to remove a previously-set bloom filter...
Definition: protocol.cpp:32
static constexpr size_t CHECKSUM_SIZE
Definition: protocol.h:34
const char * NOTFOUND
The notfound message is a reply to a getdata message which requested an object the receiving node doe...
Definition: protocol.cpp:29
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:34
const char * GETCFHEADERS
getcfheaders requests a compact filter header and the filter hashes for a range of blocks...
Definition: protocol.cpp:41
bool IsMsgWitnessBlk() const
Definition: protocol.h:426
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:342
unsigned char MessageStartChars[MESSAGE_START_SIZE]
Definition: protocol.h:38
static constexpr size_t MESSAGE_SIZE_OFFSET
Definition: protocol.h:35
static constexpr size_t MESSAGE_START_SIZE
Definition: protocol.h:31
const char * GETBLOCKS
The getblocks message requests an inv message that provides block header hashes starting from a parti...
Definition: protocol.cpp:20
void SetServiceFlagsIBDCache(bool status)
Set the current IBD status in order to figure out the desirable service flags.
Definition: protocol.cpp:152
int flags
Definition: bitcoin-tx.cpp:506
bool operator<(const CNetAddr &a, const CNetAddr &b)
Definition: netaddress.cpp:365
const char * VERACK
The verack message acknowledges a previously-received version message, informing the connecting node ...
Definition: protocol.cpp:15
bool IsMsgBlk() const
Definition: protocol.h:422
256-bit opaque blob.
Definition: uint256.h:123
SERIALIZE_METHODS(CMessageHeader, obj)
Definition: protocol.h:50
CAddress()
Definition: protocol.h:353
std::vector< std::string > serviceFlagsToStr(uint64_t flags)
Convert service flags (a bitmask of NODE_*) to human readable strings.
Definition: protocol.cpp:229
Serialization wrapper class for custom integers and enums.
Definition: serialize.h:497
CAddress(CService ipIn, ServiceFlags nServicesIn)
Definition: protocol.h:354
uint32_t type
Definition: protocol.h:438
const char * GETDATA
The getdata message requests one or more data objects from another node.
Definition: protocol.cpp:18
GetDataMsg
getdata / inv message types.
Definition: protocol.h:391
const char * CFCHECKPT
cfcheckpt is a response to a getcfcheckpt request containing a vector of evenly spaced filter headers...
Definition: protocol.cpp:44
static constexpr size_t HEADER_SIZE
Definition: protocol.h:37
#define SER_READ(obj, code)
Definition: serialize.h:173
const char * TX
The tx message transmits a single transaction.
Definition: protocol.cpp:22
Defined in BIP37.
Definition: protocol.h:397
#define VERSION
#define READWRITE(...)
Definition: serialize.h:171
Defined in BIP 339.
Definition: protocol.h:395
Defined in BIP144.
Definition: protocol.h:400
char pchMessageStart[MESSAGE_START_SIZE]
Definition: protocol.h:52
A generic txid reference (txid or wtxid).
Definition: transaction.h:394
static constexpr size_t CHECKSUM_OFFSET
Definition: protocol.h:36
const char * FILTERADD
The filteradd message tells the receiving peer to add a single element to a previously-set bloom filt...
Definition: protocol.cpp:31
const char * GETBLOCKTXN
Contains a BlockTransactionsRequest Peer should respond with "blocktxn" message.
Definition: protocol.cpp:37
Message header.
Definition: protocol.h:28
SERIALIZE_METHODS(CInv, obj)
Definition: protocol.h:413