lbrycrd/src/protocol.cpp
Wladimir J. van der Laan 41e58faf04 net: Consistent checksum handling
In principle, the checksums of P2P packets are simply 4-byte blobs which
are the first four bytes of SHA256(SHA256(payload)).

Currently they are handled as little-endian 32-bit integers half of the
time, as blobs the other half, sometimes copying the one to the other,
resulting in somewhat confused code.

This PR changes the handling to be consistent both at packet creation
and receiving, making it (I think) easier to understand.
2016-09-28 12:44:13 +02:00

190 lines
5 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2015 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "protocol.h"
#include "util.h"
#include "utilstrencodings.h"
#ifndef WIN32
# include <arpa/inet.h>
#endif
namespace NetMsgType {
const char *VERSION="version";
const char *VERACK="verack";
const char *ADDR="addr";
const char *INV="inv";
const char *GETDATA="getdata";
const char *MERKLEBLOCK="merkleblock";
const char *GETBLOCKS="getblocks";
const char *GETHEADERS="getheaders";
const char *TX="tx";
const char *HEADERS="headers";
const char *BLOCK="block";
const char *GETADDR="getaddr";
const char *MEMPOOL="mempool";
const char *PING="ping";
const char *PONG="pong";
const char *NOTFOUND="notfound";
const char *FILTERLOAD="filterload";
const char *FILTERADD="filteradd";
const char *FILTERCLEAR="filterclear";
const char *REJECT="reject";
const char *SENDHEADERS="sendheaders";
const char *FEEFILTER="feefilter";
const char *SENDCMPCT="sendcmpct";
const char *CMPCTBLOCK="cmpctblock";
const char *GETBLOCKTXN="getblocktxn";
const char *BLOCKTXN="blocktxn";
};
/** All known message types. Keep this in the same order as the list of
* messages above and in protocol.h.
*/
const static std::string allNetMessageTypes[] = {
NetMsgType::VERSION,
NetMsgType::VERACK,
NetMsgType::ADDR,
NetMsgType::INV,
NetMsgType::GETDATA,
NetMsgType::MERKLEBLOCK,
NetMsgType::GETBLOCKS,
NetMsgType::GETHEADERS,
NetMsgType::TX,
NetMsgType::HEADERS,
NetMsgType::BLOCK,
NetMsgType::GETADDR,
NetMsgType::MEMPOOL,
NetMsgType::PING,
NetMsgType::PONG,
NetMsgType::NOTFOUND,
NetMsgType::FILTERLOAD,
NetMsgType::FILTERADD,
NetMsgType::FILTERCLEAR,
NetMsgType::REJECT,
NetMsgType::SENDHEADERS,
NetMsgType::FEEFILTER,
NetMsgType::SENDCMPCT,
NetMsgType::CMPCTBLOCK,
NetMsgType::GETBLOCKTXN,
NetMsgType::BLOCKTXN,
};
const static std::vector<std::string> allNetMessageTypesVec(allNetMessageTypes, allNetMessageTypes+ARRAYLEN(allNetMessageTypes));
CMessageHeader::CMessageHeader(const MessageStartChars& pchMessageStartIn)
{
memcpy(pchMessageStart, pchMessageStartIn, MESSAGE_START_SIZE);
memset(pchCommand, 0, sizeof(pchCommand));
nMessageSize = -1;
memset(pchChecksum, 0, CHECKSUM_SIZE);
}
CMessageHeader::CMessageHeader(const MessageStartChars& pchMessageStartIn, const char* pszCommand, unsigned int nMessageSizeIn)
{
memcpy(pchMessageStart, pchMessageStartIn, MESSAGE_START_SIZE);
memset(pchCommand, 0, sizeof(pchCommand));
strncpy(pchCommand, pszCommand, COMMAND_SIZE);
nMessageSize = nMessageSizeIn;
memset(pchChecksum, 0, CHECKSUM_SIZE);
}
std::string CMessageHeader::GetCommand() const
{
return std::string(pchCommand, pchCommand + strnlen(pchCommand, COMMAND_SIZE));
}
bool CMessageHeader::IsValid(const MessageStartChars& pchMessageStartIn) const
{
// Check start string
if (memcmp(pchMessageStart, pchMessageStartIn, MESSAGE_START_SIZE) != 0)
return false;
// Check the command string for errors
for (const char* p1 = pchCommand; p1 < pchCommand + COMMAND_SIZE; p1++)
{
if (*p1 == 0)
{
// Must be all zeros after the first zero
for (; p1 < pchCommand + COMMAND_SIZE; p1++)
if (*p1 != 0)
return false;
}
else if (*p1 < ' ' || *p1 > 0x7E)
return false;
}
// Message size
if (nMessageSize > MAX_SIZE)
{
LogPrintf("CMessageHeader::IsValid(): (%s, %u bytes) nMessageSize > MAX_SIZE\n", GetCommand(), nMessageSize);
return false;
}
return true;
}
CAddress::CAddress() : CService()
{
Init();
}
CAddress::CAddress(CService ipIn, ServiceFlags nServicesIn) : CService(ipIn)
{
Init();
nServices = nServicesIn;
}
void CAddress::Init()
{
nServices = NODE_NONE;
nTime = 100000000;
}
CInv::CInv()
{
type = 0;
hash.SetNull();
}
CInv::CInv(int typeIn, const uint256& hashIn)
{
type = typeIn;
hash = hashIn;
}
bool operator<(const CInv& a, const CInv& b)
{
return (a.type < b.type || (a.type == b.type && a.hash < b.hash));
}
std::string CInv::GetCommand() const
{
std::string cmd;
if (type & MSG_WITNESS_FLAG)
cmd.append("witness-");
int masked = type & MSG_TYPE_MASK;
switch (masked)
{
case MSG_TX: return cmd.append(NetMsgType::TX);
case MSG_BLOCK: return cmd.append(NetMsgType::BLOCK);
case MSG_FILTERED_BLOCK: return cmd.append(NetMsgType::MERKLEBLOCK);
case MSG_CMPCT_BLOCK: return cmd.append(NetMsgType::CMPCTBLOCK);
default:
throw std::out_of_range(strprintf("CInv::GetCommand(): type=%d unknown type", type));
}
}
std::string CInv::ToString() const
{
return strprintf("%s %s", GetCommand(), hash.ToString());
}
const std::vector<std::string> &getAllNetMessageTypes()
{
return allNetMessageTypesVec;
}