Bitcoin Core  0.19.99
P2P Digital Currency
protocol.h
Go to the documentation of this file.
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 <serialize.h>
15 #include <uint256.h>
16 #include <version.h>
17 
18 #include <stdint.h>
19 #include <string>
20 
28 {
29 public:
30  static constexpr size_t MESSAGE_START_SIZE = 4;
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 = MESSAGE_START_SIZE + COMMAND_SIZE;
35  static constexpr size_t CHECKSUM_OFFSET = MESSAGE_SIZE_OFFSET + MESSAGE_SIZE_SIZE;
36  static constexpr size_t HEADER_SIZE = MESSAGE_START_SIZE + COMMAND_SIZE + MESSAGE_SIZE_SIZE + CHECKSUM_SIZE;
37  typedef unsigned char MessageStartChars[MESSAGE_START_SIZE];
38 
39  explicit CMessageHeader(const MessageStartChars& pchMessageStartIn);
40  CMessageHeader(const MessageStartChars& pchMessageStartIn, const char* pszCommand, unsigned int nMessageSizeIn);
41 
42  std::string GetCommand() const;
43  bool IsValid(const MessageStartChars& messageStart) const;
44 
46 
47  template <typename Stream, typename Operation>
48  inline void SerializationOp(Stream& s, Operation ser_action)
49  {
54  }
55 
58  uint32_t nMessageSize;
60 };
61 
66 namespace NetMsgType {
67 
73 extern const char *VERSION;
79 extern const char *VERACK;
85 extern const char *ADDR;
91 extern const char *INV;
96 extern const char *GETDATA;
103 extern const char *MERKLEBLOCK;
109 extern const char *GETBLOCKS;
116 extern const char *GETHEADERS;
121 extern const char *TX;
128 extern const char *HEADERS;
133 extern const char *BLOCK;
139 extern const char *GETADDR;
146 extern const char *MEMPOOL;
152 extern const char *PING;
159 extern const char *PONG;
166 extern const char *NOTFOUND;
175 extern const char *FILTERLOAD;
184 extern const char *FILTERADD;
193 extern const char *FILTERCLEAR;
200 extern const char *SENDHEADERS;
206 extern const char *FEEFILTER;
214 extern const char *SENDCMPCT;
220 extern const char *CMPCTBLOCK;
226 extern const char *GETBLOCKTXN;
232 extern const char *BLOCKTXN;
233 };
234 
235 /* Get a vector of all valid message types (see above) */
236 const std::vector<std::string> &getAllNetMessageTypes();
237 
239 enum ServiceFlags : uint64_t {
240  // NOTE: When adding here, be sure to update qt/guiutil.cpp's formatServicesStr too
241  // Nothing
243  // NODE_NETWORK means that the node is capable of serving the complete block chain. It is currently
244  // set by all Bitcoin Core non pruned nodes, and is unset by SPV clients or other light clients.
245  NODE_NETWORK = (1 << 0),
246  // NODE_GETUTXO means the node is capable of responding to the getutxo protocol request.
247  // Bitcoin Core does not support this but a patch set called Bitcoin XT does.
248  // See BIP 64 for details on how this is implemented.
249  NODE_GETUTXO = (1 << 1),
250  // NODE_BLOOM means the node is capable and willing to handle bloom-filtered connections.
251  // Bitcoin Core nodes used to support this by default, without advertising this bit,
252  // but no longer do as of protocol version 70011 (= NO_BLOOM_VERSION)
253  NODE_BLOOM = (1 << 2),
254  // NODE_WITNESS indicates that a node can be asked for blocks and transactions including
255  // witness data.
256  NODE_WITNESS = (1 << 3),
257  // NODE_NETWORK_LIMITED means the same as NODE_NETWORK with the limitation of only
258  // serving the last 288 (2 day) blocks
259  // See BIP159 for details on how this is implemented.
260  NODE_NETWORK_LIMITED = (1 << 10),
261 
262  // Bits 24-31 are reserved for temporary experiments. Just pick a bit that
263  // isn't getting used, or one not being used much, and notify the
264  // bitcoin-development mailing list. Remember that service bits are just
265  // unauthenticated advertisements, so your code must be robust against
266  // collisions and other cases where nodes may be advertising a service they
267  // do not actually support. Other service bits should be allocated via the
268  // BIP process.
269 };
270 
296 
298 void SetServiceFlagsIBDCache(bool status);
299 
305 static inline bool HasAllDesirableServiceFlags(ServiceFlags services) {
306  return !(GetDesirableServiceFlags(services) & (~services));
307 }
308 
313 static inline bool MayHaveUsefulAddressDB(ServiceFlags services) {
314  return (services & NODE_NETWORK) || (services & NODE_NETWORK_LIMITED);
315 }
316 
318 class CAddress : public CService
319 {
320 public:
321  CAddress();
322  explicit CAddress(CService ipIn, ServiceFlags nServicesIn);
323 
324  void Init();
325 
327 
328  template <typename Stream, typename Operation>
329  inline void SerializationOp(Stream& s, Operation ser_action)
330  {
331  if (ser_action.ForRead())
332  Init();
333  int nVersion = s.GetVersion();
334  if (s.GetType() & SER_DISK)
335  READWRITE(nVersion);
336  if ((s.GetType() & SER_DISK) ||
337  (nVersion >= CADDR_TIME_VERSION && !(s.GetType() & SER_GETHASH)))
338  READWRITE(nTime);
339  uint64_t nServicesInt = nServices;
340  READWRITE(nServicesInt);
341  nServices = static_cast<ServiceFlags>(nServicesInt);
342  READWRITEAS(CService, *this);
343  }
344 
345  // TODO: make private (improves encapsulation)
346 public:
348 
349  // disk and network only
350  unsigned int nTime;
351 };
352 
354 const uint32_t MSG_WITNESS_FLAG = 1 << 30;
355 const uint32_t MSG_TYPE_MASK = 0xffffffff >> 2;
356 
362 {
364  MSG_TX = 1,
366  // The following can only occur in getdata. Invs always use TX or BLOCK.
372 };
373 
375 class CInv
376 {
377 public:
378  CInv();
379  CInv(int typeIn, const uint256& hashIn);
380 
382 
383  template <typename Stream, typename Operation>
384  inline void SerializationOp(Stream& s, Operation ser_action)
385  {
386  READWRITE(type);
387  READWRITE(hash);
388  }
389 
390  friend bool operator<(const CInv& a, const CInv& b);
391 
392  std::string GetCommand() const;
393  std::string ToString() const;
394 
395 public:
396  int type;
398 };
399 
400 #endif // BITCOIN_PROTOCOL_H
const char * PING
The ping message is sent periodically to help confirm that the receiving peer is still connected...
Definition: protocol.cpp:31
const char * FILTERLOAD
The filterload message tells the receiving peer to filter all relayed transactions and requested merk...
Definition: protocol.cpp:34
const char * MERKLEBLOCK
The merkleblock message is a reply to a getdata message which requested a block using the inventory t...
Definition: protocol.cpp:23
uint8_t pchChecksum[CHECKSUM_SIZE]
Definition: protocol.h:59
const char * BLOCKTXN
Contains a BlockTransactions.
Definition: protocol.cpp:42
ServiceFlags
nServices flags
Definition: protocol.h:239
static constexpr size_t MESSAGE_SIZE_SIZE
Definition: protocol.h:32
Defined in BIP144.
Definition: protocol.h:370
const std::vector< std::string > & getAllNetMessageTypes()
Definition: protocol.cpp:198
const char * GETADDR
The getaddr message requests an addr message from the receiving node, preferably one with lots of IP ...
Definition: protocol.cpp:29
Defined in BIP152.
Definition: protocol.h:368
inv message data
Definition: protocol.h:375
const char * SENDCMPCT
Contains a 1-byte bool and 8-byte LE version number.
Definition: protocol.cpp:39
char pchCommand[COMMAND_SIZE]
Definition: protocol.h:57
void SerializationOp(Stream &s, Operation ser_action)
Definition: protocol.h:329
Defined in BIP144.
Definition: protocol.h:369
ADD_SERIALIZE_METHODS
Definition: protocol.h:326
CMessageHeader(const MessageStartChars &pchMessageStartIn)
Definition: protocol.cpp:77
void SerializationOp(Stream &s, Operation ser_action)
Definition: protocol.h:48
GetDataMsg
getdata / inv message types.
Definition: protocol.h:361
const uint32_t MSG_WITNESS_FLAG
getdata message type flags
Definition: protocol.h:354
uint32_t nMessageSize
Definition: protocol.h:58
const uint32_t MSG_TYPE_MASK
Definition: protocol.h:355
std::string GetCommand() const
Definition: protocol.cpp:94
#define READWRITEAS(type, obj)
Definition: serialize.h:187
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:32
bool IsValid(const MessageStartChars &messageStart) const
Definition: protocol.cpp:99
const char * HEADERS
The headers message sends one or more block headers to a node which previously requested certain head...
Definition: protocol.cpp:27
const char * INV
The inv message (inventory message) transmits one or more inventories of objects known to the transmi...
Definition: protocol.cpp:21
ServiceFlags GetDesirableServiceFlags(ServiceFlags services)
Gets the set of service flags which are "desirable" for a given peer.
Definition: protocol.cpp:130
const char * GETHEADERS
The getheaders message requests a headers message that provides block headers starting from a particu...
Definition: protocol.cpp:25
static constexpr size_t COMMAND_SIZE
Definition: protocol.h:31
static bool HasAllDesirableServiceFlags(ServiceFlags services)
A shortcut for (services & GetDesirableServiceFlags(services)) == GetDesirableServiceFlags(services)...
Definition: protocol.h:305
Bitcoin protocol message types.
Definition: protocol.cpp:17
int type
Definition: protocol.h:396
A combination of a network address (CNetAddr) and a (TCP) port.
Definition: netaddress.h:150
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:37
A CService with information about it as peer.
Definition: protocol.h:318
uint256 hash
Definition: protocol.h:397
const char * ADDR
The addr (IP address) message relays connection information for peers on the network.
Definition: protocol.cpp:20
const char * FILTERCLEAR
The filterclear message tells the receiving peer to remove a previously-set bloom filter...
Definition: protocol.cpp:36
static constexpr size_t CHECKSUM_SIZE
Definition: protocol.h:33
const char * NOTFOUND
The notfound message is a reply to a getdata message which requested an object the receiving node doe...
Definition: protocol.cpp:33
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:38
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:313
unsigned char MessageStartChars[MESSAGE_START_SIZE]
Definition: protocol.h:37
static constexpr size_t MESSAGE_SIZE_OFFSET
Definition: protocol.h:34
static constexpr size_t MESSAGE_START_SIZE
Definition: protocol.h:30
const char * GETBLOCKS
The getblocks message requests an inv message that provides block header hashes starting from a parti...
Definition: protocol.cpp:24
void SetServiceFlagsIBDCache(bool status)
Set the current IBD status in order to figure out the desirable service flags.
Definition: protocol.cpp:137
ADD_SERIALIZE_METHODS
Definition: protocol.h:381
bool operator<(const CNetAddr &a, const CNetAddr &b)
Definition: netaddress.cpp:362
const char * VERACK
The verack message acknowledges a previously-received version message, informing the connecting node ...
Definition: protocol.cpp:19
256-bit opaque blob.
Definition: uint256.h:120
unsigned int nTime
Definition: protocol.h:350
ServiceFlags nServices
Definition: protocol.h:347
static const int CADDR_TIME_VERSION
nTime field added to CAddress, starting with this version; if possible, avoid requesting addresses no...
Definition: version.h:25
const char * GETDATA
The getdata message requests one or more data objects from another node.
Definition: protocol.cpp:22
static constexpr size_t HEADER_SIZE
Definition: protocol.h:36
void SerializationOp(Stream &s, Operation ser_action)
Definition: protocol.h:384
const char * TX
The tx message transmits a single transaction.
Definition: protocol.cpp:26
#define VERSION
#define READWRITE(...)
Definition: serialize.h:186
char pchMessageStart[MESSAGE_START_SIZE]
Definition: protocol.h:56
Defined in BIP37.
Definition: protocol.h:367
static constexpr size_t CHECKSUM_OFFSET
Definition: protocol.h:35
const char * FILTERADD
The filteradd message tells the receiving peer to add a single element to a previously-set bloom filt...
Definition: protocol.cpp:35
const char * GETBLOCKTXN
Contains a BlockTransactionsRequest Peer should respond with "blocktxn" message.
Definition: protocol.cpp:41
Message header.
Definition: protocol.h:27