thehub/hub/server/protocol.h

/*
 * This file is part of the Flowee project
 * Copyright (C) 2009-2010 Satoshi Nakamoto
 * Copyright (C) 2009-2015 The Bitcoin Core developers
 * Copyright (C) 2019 Tom Zander <tom@flowee.org>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef __cplusplus
#error This header can only be compiled as C++.
#endif

#ifndef FLOWEE_PROTOCOL_H
#define FLOWEE_PROTOCOL_H

#include "netbase.h"
#include "serialize.h"
#include "uint256.h"
#include "version.h"

#define MESSAGE_START_SIZE 4

/** Message header.
 * (4) message start.
 * (12) command.
 * (4) size.
 * (4) checksum.
 */
class CMessageHeader
{
public:
    typedef unsigned char MessageStartChars[MESSAGE_START_SIZE];

    CMessageHeader(const MessageStartChars& pchMessageStartIn);
    CMessageHeader(const MessageStartChars& pchMessageStartIn, const char* pszCommand, unsigned int nMessageSizeIn);

    std::string GetCommand() const;
    bool IsValid(const MessageStartChars& messageStart) const;

    ADD_SERIALIZE_METHODS

    template <typename Stream, typename Operation>
    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion)
    {
        READWRITE(FLATDATA(pchMessageStart));
        READWRITE(FLATDATA(pchCommand));
        READWRITE(nMessageSize);
        READWRITE(nChecksum);
    }

    // TODO: make private (improves encapsulation)
public:
    enum {
        COMMAND_SIZE = 12,
        MESSAGE_SIZE_SIZE = sizeof(int),
        CHECKSUM_SIZE = sizeof(int),

        MESSAGE_SIZE_OFFSET = MESSAGE_START_SIZE + COMMAND_SIZE,
        CHECKSUM_OFFSET = MESSAGE_SIZE_OFFSET + MESSAGE_SIZE_SIZE,
        HEADER_SIZE = MESSAGE_START_SIZE + COMMAND_SIZE + MESSAGE_SIZE_SIZE + CHECKSUM_SIZE
    };
    char pchMessageStart[MESSAGE_START_SIZE];
    char pchCommand[COMMAND_SIZE];
    unsigned int nMessageSize;
    unsigned int nChecksum;
};

/**
 * Bitcoin protocol message types. When adding new message types, don't forget
 * to update allNetMessageTypes in protocol.cpp.
 */
namespace NetMsgType {

/**
 * The version message provides information about the transmitting node to the
 * receiving node at the beginning of a connection.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#version
 */
extern const char *VERSION;
/**
 * The verack message acknowledges a previously-received version message,
 * informing the connecting node that it can begin to send other messages.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#verack
 */
extern const char *VERACK;
/**
 * The addr (IP address) message relays connection information for peers on the
 * network.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#addr
 */
extern const char *ADDR;
/**
 * The inv message (inventory message) transmits one or more inventories of
 * objects known to the transmitting peer.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#inv
 */
extern const char *INV;
/**
 * The getdata message requests one or more data objects from another node.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#getdata
 */
extern const char *GETDATA;
/**
 * The merkleblock message is a reply to a getdata message which requested a
 * block using the inventory type MSG_MERKLEBLOCK.
 * @since protocol version 70001 as described by BIP37.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#merkleblock
 */
extern const char *MERKLEBLOCK;
/**
 * The getblocks message requests an inv message that provides block header
 * hashes starting from a particular point in the block chain.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#getblocks
 */
extern const char *GETBLOCKS;
/**
 * The getheaders message requests a headers message that provides block
 * headers starting from a particular point in the block chain.
 * @since protocol version 31800.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#getheaders
 */
extern const char *GETHEADERS;
/**
 * The tx message transmits a single transaction.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#tx
 */
extern const char *TX;
/**
 * The headers message sends one or more block headers to a node which
 * previously requested certain headers with a getheaders message.
 * @since protocol version 31800.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#headers
 */
extern const char *HEADERS;
/**
 * The block message transmits a single serialized block.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#block
 */
extern const char *BLOCK;
/**
 * The thinblock message transmits a single serialized thinblock.
 */
extern const char *THINBLOCK;
/**
 * The xthinblock message transmits a single serializexd xthinblock.
 */
extern const char *XTHINBLOCK;
/**
 * The xblocktx message transmits a single serialized xblocktx.
 */
extern const char *XBLOCKTX;
/**
 * The get_xblocktx message transmits a single serialized get_xblocktx.
 */
extern const char *GET_XBLOCKTX;
/**
 * The get_xthin message transmits a single serialized get_xthin.
 */
extern const char *GET_XTHIN;

/**
 * The getaddr message requests an addr message from the receiving node,
 * preferably one with lots of IP addresses of other receiving nodes.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#getaddr
 */
extern const char *GETADDR;
/**
 * The mempool message requests the TXIDs of transactions that the receiving
 * node has verified as valid but which have not yet appeared in a block.
 * @since protocol version 60002.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#mempool
 */
extern const char *MEMPOOL;
/**
 * The ping message is sent periodically to help confirm that the receiving
 * peer is still connected.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#ping
 */
extern const char *PING;
/**
 * The pong message replies to a ping message, proving to the pinging node that
 * the ponging node is still alive.
 * @since protocol version 60001 as described by BIP31.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#pong
 */
extern const char *PONG;
/**
 * The notfound message is a reply to a getdata message which requested an
 * object the receiving node does not have available for relay.
 * @ince protocol version 70001.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#notfound
 */
extern const char *NOTFOUND;
/**
 * The filterload message tells the receiving peer to filter all relayed
 * transactions and requested merkle blocks through the provided filter.
 * @since protocol version 70001 as described by BIP37.
 *   Only available with service bit NODE_BLOOM since protocol version
 *   70011 as described by BIP111.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#filterload
 */
extern const char *FILTERLOAD;
/**
 * The filteradd message tells the receiving peer to add a single element to a
 * previously-set bloom filter, such as a new public key.
 * @since protocol version 70001 as described by BIP37.
 *   Only available with service bit NODE_BLOOM since protocol version
 *   70011 as described by BIP111.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#filteradd
 */
extern const char *FILTERADD;
/**
 * The filterclear message tells the receiving peer to remove a previously-set
 * bloom filter.
 * @since protocol version 70001 as described by BIP37.
 *   Only available with service bit NODE_BLOOM since protocol version
 *   70011 as described by BIP111.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#filterclear
 */
extern const char *FILTERCLEAR;
/**
 * The reject message informs the receiving node that one of its previous
 * messages has been rejected.
 * @since protocol version 70002 as described by BIP61.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#reject
 */
extern const char *REJECT;
/**
 * Indicates that a node prefers to receive new block announcements via a
 * "headers" message rather than an "inv".
 * @since protocol version 70012 as described by BIP130.
 * @see https://developer.bitcoin.org/reference/p2p_networking.html#sendheaders
 */
extern const char *SENDHEADERS;

/**
 * Version2, request a verack2.
 * @since protocol version 80002
 */
extern const char *VERSION2;
/**
 * verack2, a followup message to verack since we can't extend or change old
 * messages. This one is meant to exchange our port number.
 * @since protocol version 80002
 */
extern const char *VERACK2;
/**
 * Send this if your node prefers to receive new block announcements
 * and transactions directly without INVs
 * @since protocol version 80000
 */
extern const char *XPEDITEDREQUEST;
/**
 * Block or transactions sent without explicit solicitation
 * @since protocol version 80000
 */
extern const char *XPEDITEDBLK;
/**
 * Block or transactions sent without explicit solicitation
 * @since protocol version 80000
 */
extern const char *XPEDITEDTXN;
/**
 * Double spend proof
 */
extern const char *DSPROOF;
}

/* Get a vector of all valid message types (see above) */
const std::vector<std::string> &getAllNetMessageTypes();

/** nServices flags */
enum {
    // NODE_NETWORK means that the node is capable of serving the block chain. It is currently
    // set by all Flowee nodes, and is unset by SPV clients or other peers that just want
    // network services but don't provide them.
    NODE_NETWORK = (1 << 0),
    // NODE_BLOOM means the node is capable and willing to handle bloom-filtered connections.
    // Bitcoin Core nodes used to support this by default, without advertising this bit,
    // but no longer do as of protocol version 70011 (= NO_BLOOM_VERSION)
    NODE_BLOOM = (1 << 2),

    // NODE_XTHIN means the node supports Xtreme Thinblocks
    // If this is turned off then the node will not service xthin requests nor
    // make xthin requests
    NODE_XTHIN = (1 << 4),

    // NODE_CASH means the node supports and follows the 'UAHF' chain.
    NODE_BITCOIN_CASH = (1 << 5),

    // obsolete
    NODE_WEAKBLOCKS = (1 << 7),

    // NODE_GRAPHENE means the node supports Graphene blocks
    // If this is turned off then the node will not service graphene requests nor
    // make graphene requests
    NODE_GRAPHENE = (1 << 6),
    // NODE_CF means that the node supports BIP 157/158 style
    // compact filters on block data
    NODE_CF = (1 << 8),
    // NODE_NETWORK_LIMITED means the same as NODE_NETWORK with the limitation
    // of only serving the last 288 (2 day) blocks
    // See BIP159 for details on how this is implemented.
    NODE_NETWORK_LIMITED = (1 << 10),
    // indicates if node is using extversion
    NODE_EXTVERSION = (1 << 11),

    // Bits 24-31 are reserved for temporary experiments. Just pick a bit that
    // isn't getting used, or one not being used much, and notify the
    // bitcoin-development mailing list. Remember that service bits are just
    // unauthenticated advertisements, so your code must be robust against
    // collisions and other cases where nodes may be advertising a service they
    // do not actually support. Other service bits should be allocated via the
    // BIP process.
};

/** A CService with information about it as peer */
class CAddress : public CService
{
public:
    CAddress();
    explicit CAddress(CService ipIn, uint64_t nServicesIn = NODE_NETWORK);

    void Init();

    ADD_SERIALIZE_METHODS

    template <typename Stream, typename Operation>
    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion)
    {
        if (ser_action.ForRead())
            Init();
        if (nType & SER_DISK)
            READWRITE(nVersion);
        if ((nType & SER_DISK) ||
            (nVersion >= CADDR_TIME_VERSION && !(nType & SER_GETHASH)))
            READWRITE(nTime);
        READWRITE(nServices);
        READWRITE(*(CService*)this);
    }

    // TODO: make private (improves encapsulation)
public:
    uint64_t nServices;

    // disk and network only
    unsigned int nTime;
};

/** inv message data */
class CInv
{
public:
    CInv();
    CInv(int typeIn, const uint256& hashIn);

    ADD_SERIALIZE_METHODS

    template <typename Stream, typename Operation>
    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
        READWRITE(type);
        READWRITE(hash);
    }

    friend bool operator<(const CInv& a, const CInv& b);

    bool IsKnownType() const;
    const char* GetCommand() const;
    std::string ToString() const;

    inline const uint256 &getHash() const {
        return hash;
    }

public:
    // TODO: make private (improves encapsulation)
    int type;
    uint256 hash;
};

enum {
    MSG_TX = 1,
    MSG_BLOCK,
    // Nodes may always request a MSG_FILTERED_BLOCK in a getdata, however,
    // MSG_FILTERED_BLOCK should not appear in any invs except as a part of getdata.
    MSG_FILTERED_BLOCK,
    // BUIP010 Xtreme Thinblocks: a thin block contains all the transactions hashes in a block
    // and also provides the missing transactions that are needed at the other end to reconstruct the block
    MSG_THINBLOCK,
    // BUIP010 Xtreme Thinblocks: an Xtreme thin block contains the first 8 bytes of all the tx hashes 
    // and also provides the missing transactions that are needed at the other end to reconstruct the block
    MSG_XTHINBLOCK,

    MSG_DOUBLESPENDPROOF = 0x94a0
};


inline Log::SilentItem operator<<(Log::SilentItem item, const CInv&) { return item; }
inline Log::Item operator<<(Log::Item item, const CInv &inv) {
    const bool old = item.useSpace();
    item.nospace() << inv.GetCommand() << '{' << inv.getHash() << '}';
    if (old)
        return item.space();
    return item;
}


#endif // BITCOIN_PROTOCOL_H