ddnet/src/engine/shared/network_conn.cpp
2022-02-15 00:12:52 +01:00

495 lines
13 KiB
C++

/* (c) Magnus Auvinen. See licence.txt in the root of the distribution for more information. */
/* If you are missing that file, acquire a complete release at teeworlds.com. */
#include "config.h"
#include "network.h"
#include <base/system.h>
SECURITY_TOKEN ToSecurityToken(unsigned char *pData)
{
return (int)pData[0] | (pData[1] << 8) | (pData[2] << 16) | (pData[3] << 24);
}
void CNetConnection::ResetStats()
{
mem_zero(&m_Stats, sizeof(m_Stats));
mem_zero(&m_PeerAddr, sizeof(m_PeerAddr));
m_LastUpdateTime = 0;
}
void CNetConnection::Reset(bool Rejoin)
{
m_Sequence = 0;
m_Ack = 0;
m_PeerAck = 0;
m_RemoteClosed = 0;
if(!Rejoin)
{
m_TimeoutProtected = false;
m_TimeoutSituation = false;
m_State = NET_CONNSTATE_OFFLINE;
m_Token = -1;
m_SecurityToken = NET_SECURITY_TOKEN_UNKNOWN;
m_Sixup = false;
}
m_LastSendTime = 0;
m_LastRecvTime = 0;
//m_LastUpdateTime = 0;
//mem_zero(&m_PeerAddr, sizeof(m_PeerAddr));
m_UnknownSeq = false;
m_Buffer.Init();
mem_zero(&m_Construct, sizeof(m_Construct));
}
const char *CNetConnection::ErrorString()
{
return m_aErrorString;
}
void CNetConnection::SetError(const char *pString)
{
str_copy(m_aErrorString, pString, sizeof(m_aErrorString));
}
void CNetConnection::Init(NETSOCKET Socket, bool BlockCloseMsg)
{
Reset();
ResetStats();
m_Socket = Socket;
m_BlockCloseMsg = BlockCloseMsg;
mem_zero(m_aErrorString, sizeof(m_aErrorString));
}
void CNetConnection::AckChunks(int Ack)
{
while(true)
{
CNetChunkResend *pResend = m_Buffer.First();
if(!pResend)
break;
if(CNetBase::IsSeqInBackroom(pResend->m_Sequence, Ack))
m_Buffer.PopFirst();
else
break;
}
}
void CNetConnection::SignalResend()
{
m_Construct.m_Flags |= NET_PACKETFLAG_RESEND;
}
int CNetConnection::Flush()
{
int NumChunks = m_Construct.m_NumChunks;
if(!NumChunks && !m_Construct.m_Flags)
return 0;
// send of the packets
m_Construct.m_Ack = m_Ack;
CNetBase::SendPacket(m_Socket, &m_PeerAddr, &m_Construct, m_SecurityToken, m_Sixup);
// update send times
m_LastSendTime = time_get();
// clear construct so we can start building a new package
mem_zero(&m_Construct, sizeof(m_Construct));
return NumChunks;
}
int CNetConnection::QueueChunkEx(int Flags, int DataSize, const void *pData, int Sequence)
{
if(m_State == NET_CONNSTATE_OFFLINE || m_State == NET_CONNSTATE_ERROR)
return -1;
unsigned char *pChunkData;
// check if we have space for it, if not, flush the connection
if(m_Construct.m_DataSize + DataSize + NET_MAX_CHUNKHEADERSIZE > (int)sizeof(m_Construct.m_aChunkData) - (int)sizeof(SECURITY_TOKEN))
Flush();
// pack all the data
CNetChunkHeader Header;
Header.m_Flags = Flags;
Header.m_Size = DataSize;
Header.m_Sequence = Sequence;
pChunkData = &m_Construct.m_aChunkData[m_Construct.m_DataSize];
pChunkData = Header.Pack(pChunkData, m_Sixup ? 6 : 4);
mem_copy(pChunkData, pData, DataSize);
pChunkData += DataSize;
//
m_Construct.m_NumChunks++;
m_Construct.m_DataSize = (int)(pChunkData - m_Construct.m_aChunkData);
// set packet flags as well
if(Flags & NET_CHUNKFLAG_VITAL && !(Flags & NET_CHUNKFLAG_RESEND))
{
// save packet if we need to resend
CNetChunkResend *pResend = m_Buffer.Allocate(sizeof(CNetChunkResend) + DataSize);
if(pResend)
{
pResend->m_Sequence = Sequence;
pResend->m_Flags = Flags;
pResend->m_DataSize = DataSize;
pResend->m_pData = (unsigned char *)(pResend + 1);
pResend->m_FirstSendTime = time_get();
pResend->m_LastSendTime = pResend->m_FirstSendTime;
mem_copy(pResend->m_pData, pData, DataSize);
}
else
{
// out of buffer, don't save the packet and hope nobody will ask for resend
return -1;
}
}
return 0;
}
int CNetConnection::QueueChunk(int Flags, int DataSize, const void *pData)
{
if(Flags & NET_CHUNKFLAG_VITAL)
m_Sequence = (m_Sequence + 1) % NET_MAX_SEQUENCE;
return QueueChunkEx(Flags, DataSize, pData, m_Sequence);
}
void CNetConnection::SendControl(int ControlMsg, const void *pExtra, int ExtraSize)
{
// send the control message
m_LastSendTime = time_get();
CNetBase::SendControlMsg(m_Socket, &m_PeerAddr, m_Ack, ControlMsg, pExtra, ExtraSize, m_SecurityToken, m_Sixup);
}
void CNetConnection::ResendChunk(CNetChunkResend *pResend)
{
QueueChunkEx(pResend->m_Flags | NET_CHUNKFLAG_RESEND, pResend->m_DataSize, pResend->m_pData, pResend->m_Sequence);
pResend->m_LastSendTime = time_get();
}
void CNetConnection::Resend()
{
for(CNetChunkResend *pResend = m_Buffer.First(); pResend; pResend = m_Buffer.Next(pResend))
ResendChunk(pResend);
}
int CNetConnection::Connect(NETADDR *pAddr)
{
if(State() != NET_CONNSTATE_OFFLINE)
return -1;
// init connection
Reset();
m_PeerAddr = *pAddr;
mem_zero(m_aErrorString, sizeof(m_aErrorString));
m_State = NET_CONNSTATE_CONNECT;
SendControl(NET_CTRLMSG_CONNECT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC));
return 0;
}
void CNetConnection::Disconnect(const char *pReason)
{
if(State() == NET_CONNSTATE_OFFLINE)
return;
if(m_RemoteClosed == 0)
{
if(!m_TimeoutSituation)
{
if(pReason)
SendControl(NET_CTRLMSG_CLOSE, pReason, str_length(pReason) + 1);
else
SendControl(NET_CTRLMSG_CLOSE, 0, 0);
}
if(pReason != m_aErrorString)
{
m_aErrorString[0] = 0;
if(pReason)
str_copy(m_aErrorString, pReason, sizeof(m_aErrorString));
}
}
Reset();
}
void CNetConnection::DirectInit(NETADDR &Addr, SECURITY_TOKEN SecurityToken, SECURITY_TOKEN Token, bool Sixup)
{
Reset();
m_State = NET_CONNSTATE_ONLINE;
m_PeerAddr = Addr;
mem_zero(m_aErrorString, sizeof(m_aErrorString));
int64_t Now = time_get();
m_LastSendTime = Now;
m_LastRecvTime = Now;
m_LastUpdateTime = Now;
m_SecurityToken = SecurityToken;
m_Token = Token;
m_Sixup = Sixup;
}
int CNetConnection::Feed(CNetPacketConstruct *pPacket, NETADDR *pAddr, SECURITY_TOKEN SecurityToken)
{
if(!m_Sixup && State() != NET_CONNSTATE_OFFLINE && m_SecurityToken != NET_SECURITY_TOKEN_UNKNOWN && m_SecurityToken != NET_SECURITY_TOKEN_UNSUPPORTED)
{
// supposed to have a valid token in this packet, check it
if(pPacket->m_DataSize < (int)sizeof(m_SecurityToken))
return 0;
pPacket->m_DataSize -= sizeof(m_SecurityToken);
if(m_SecurityToken != ToSecurityToken(&pPacket->m_aChunkData[pPacket->m_DataSize]))
{
if(g_Config.m_Debug)
dbg_msg("security", "token mismatch, expected %d got %d", m_SecurityToken, ToSecurityToken(&pPacket->m_aChunkData[pPacket->m_DataSize]));
return 0;
}
}
if(m_Sixup && SecurityToken != m_Token)
return 0;
// check if actual ack value is valid(own sequence..latest peer ack)
if(m_Sequence >= m_PeerAck)
{
if(pPacket->m_Ack < m_PeerAck || pPacket->m_Ack > m_Sequence)
return 0;
}
else
{
if(pPacket->m_Ack < m_PeerAck && pPacket->m_Ack > m_Sequence)
return 0;
}
m_PeerAck = pPacket->m_Ack;
int64_t Now = time_get();
// check if resend is requested
if(pPacket->m_Flags & NET_PACKETFLAG_RESEND)
Resend();
//
if(pPacket->m_Flags & NET_PACKETFLAG_CONTROL)
{
int CtrlMsg = pPacket->m_aChunkData[0];
if(CtrlMsg == NET_CTRLMSG_CLOSE)
{
if(net_addr_comp(&m_PeerAddr, pAddr) == 0)
{
m_State = NET_CONNSTATE_ERROR;
m_RemoteClosed = 1;
char aStr[128] = {0};
if(pPacket->m_DataSize > 1)
{
// make sure to sanitize the error string form the other party
str_copy(aStr, (char *)&pPacket->m_aChunkData[1], minimum(pPacket->m_DataSize, (int)sizeof(aStr)));
str_sanitize_cc(aStr);
}
if(!m_BlockCloseMsg)
{
// set the error string
SetError(aStr);
}
if(g_Config.m_Debug)
dbg_msg("conn", "closed reason='%s'", aStr);
}
return 0;
}
else
{
if(State() == NET_CONNSTATE_OFFLINE)
{
if(CtrlMsg == NET_CTRLMSG_CONNECT)
{
if(net_addr_comp_noport(&m_PeerAddr, pAddr) == 0 && time_get() - m_LastUpdateTime < time_freq() * 3)
return 0;
// send response and init connection
Reset();
m_State = NET_CONNSTATE_PENDING;
m_PeerAddr = *pAddr;
mem_zero(m_aErrorString, sizeof(m_aErrorString));
m_LastSendTime = Now;
m_LastRecvTime = Now;
m_LastUpdateTime = Now;
if(m_SecurityToken == NET_SECURITY_TOKEN_UNKNOWN && pPacket->m_DataSize >= (int)(1 + sizeof(SECURITY_TOKEN_MAGIC) + sizeof(m_SecurityToken)) && !mem_comp(&pPacket->m_aChunkData[1], SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC)))
{
m_SecurityToken = NET_SECURITY_TOKEN_UNSUPPORTED;
if(g_Config.m_Debug)
dbg_msg("security", "generated token %d", m_SecurityToken);
}
else
{
if(g_Config.m_Debug)
dbg_msg("security", "token not supported by client (packet size %d)", pPacket->m_DataSize);
m_SecurityToken = NET_SECURITY_TOKEN_UNSUPPORTED;
}
SendControl(NET_CTRLMSG_CONNECTACCEPT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC));
if(g_Config.m_Debug)
dbg_msg("connection", "got connection, sending connect+accept");
}
}
else if(State() == NET_CONNSTATE_CONNECT)
{
// connection made
if(CtrlMsg == NET_CTRLMSG_CONNECTACCEPT)
{
if(m_SecurityToken == NET_SECURITY_TOKEN_UNKNOWN && pPacket->m_DataSize >= (int)(1 + sizeof(SECURITY_TOKEN_MAGIC) + sizeof(m_SecurityToken)) && !mem_comp(&pPacket->m_aChunkData[1], SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC)))
{
m_SecurityToken = ToSecurityToken(&pPacket->m_aChunkData[1 + sizeof(SECURITY_TOKEN_MAGIC)]);
if(g_Config.m_Debug)
dbg_msg("security", "got token %d", m_SecurityToken);
}
else
{
m_SecurityToken = NET_SECURITY_TOKEN_UNSUPPORTED;
if(g_Config.m_Debug)
dbg_msg("security", "token not supported by server");
}
m_LastRecvTime = Now;
SendControl(NET_CTRLMSG_ACCEPT, 0, 0);
m_State = NET_CONNSTATE_ONLINE;
if(g_Config.m_Debug)
dbg_msg("connection", "got connect+accept, sending accept. connection online");
}
}
}
}
else
{
if(State() == NET_CONNSTATE_PENDING)
{
m_LastRecvTime = Now;
m_State = NET_CONNSTATE_ONLINE;
if(g_Config.m_Debug)
dbg_msg("connection", "connecting online");
}
}
if(State() == NET_CONNSTATE_ONLINE)
{
m_LastRecvTime = Now;
AckChunks(pPacket->m_Ack);
}
return 1;
}
int CNetConnection::Update()
{
int64_t Now = time_get();
if(State() == NET_CONNSTATE_ERROR && m_TimeoutSituation && (Now - m_LastRecvTime) > time_freq() * g_Config.m_ConnTimeoutProtection)
{
m_TimeoutSituation = false;
SetError("Timeout Protection over");
}
if(State() == NET_CONNSTATE_OFFLINE || State() == NET_CONNSTATE_ERROR)
return 0;
m_TimeoutSituation = false;
// check for timeout
if(State() != NET_CONNSTATE_OFFLINE &&
State() != NET_CONNSTATE_CONNECT &&
(Now - m_LastRecvTime) > time_freq() * g_Config.m_ConnTimeout)
{
m_State = NET_CONNSTATE_ERROR;
SetError("Timeout");
m_TimeoutSituation = true;
}
// fix resends
if(m_Buffer.First())
{
CNetChunkResend *pResend = m_Buffer.First();
// check if we have some really old stuff laying around and abort if not acked
if(Now - pResend->m_FirstSendTime > time_freq() * g_Config.m_ConnTimeout)
{
m_State = NET_CONNSTATE_ERROR;
char aBuf[512];
str_format(aBuf, sizeof(aBuf), "Too weak connection (not acked for %d seconds)", g_Config.m_ConnTimeout);
SetError(aBuf);
m_TimeoutSituation = true;
}
else
{
// resend packet if we haven't got it acked in 1 second
if(Now - pResend->m_LastSendTime > time_freq())
ResendChunk(pResend);
}
}
// send keep alives if nothing has happened for 250ms
if(State() == NET_CONNSTATE_ONLINE)
{
if(time_get() - m_LastSendTime > time_freq() / 2) // flush connection after 500ms if needed
{
int NumFlushedChunks = Flush();
if(NumFlushedChunks && g_Config.m_Debug)
dbg_msg("connection", "flushed connection due to timeout. %d chunks.", NumFlushedChunks);
}
if(time_get() - m_LastSendTime > time_freq())
SendControl(NET_CTRLMSG_KEEPALIVE, 0, 0);
}
else if(State() == NET_CONNSTATE_CONNECT)
{
if(time_get() - m_LastSendTime > time_freq() / 2) // send a new connect every 500ms
SendControl(NET_CTRLMSG_CONNECT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC));
}
else if(State() == NET_CONNSTATE_PENDING)
{
if(time_get() - m_LastSendTime > time_freq() / 2) // send a new connect/accept every 500ms
SendControl(NET_CTRLMSG_CONNECTACCEPT, SECURITY_TOKEN_MAGIC, sizeof(SECURITY_TOKEN_MAGIC));
}
return 0;
}
void CNetConnection::SetTimedOut(const NETADDR *pAddr, int Sequence, int Ack, SECURITY_TOKEN SecurityToken, CStaticRingBuffer<CNetChunkResend, NET_CONN_BUFFERSIZE> *pResendBuffer, bool Sixup)
{
int64_t Now = time_get();
m_Sequence = Sequence;
m_Ack = Ack;
m_RemoteClosed = 0;
m_State = NET_CONNSTATE_ONLINE;
m_PeerAddr = *pAddr;
mem_zero(m_aErrorString, sizeof(m_aErrorString));
m_LastSendTime = Now;
m_LastRecvTime = Now;
m_LastUpdateTime = Now;
m_SecurityToken = SecurityToken;
m_Sixup = Sixup;
// copy resend buffer
m_Buffer.Init();
while(pResendBuffer->First())
{
CNetChunkResend *pFirst = pResendBuffer->First();
CNetChunkResend *pResend = m_Buffer.Allocate(sizeof(CNetChunkResend) + pFirst->m_DataSize);
mem_copy(pResend, pFirst, sizeof(CNetChunkResend) + pFirst->m_DataSize);
pResendBuffer->PopFirst();
}
}