qboolean Netchan_Validate(netchan_t *chan, qboolean *frag_message, unsigned int *fragid, int *frag_offset, int *frag_length)
{
for (int i = 0; i < MAX_STREAMS; i++)
{
if (!frag_message[i])
continue;
#ifndef REHLDS_FIXES
if (FRAG_GETID(fragid[i]) > MAX_FRAGMENTS || FRAG_GETCOUNT(fragid[i]) > MAX_FRAGMENTS)
{
return FALSE;
}
if ((unsigned int)frag_length[i] > 0x800 || (unsigned int)frag_offset[i] > 0x4000)
{
return FALSE;
}
#else // REHLDS_FIXES
// total fragments should be <= MAX_FRAGMENTS and current fragment can't be > total fragments
if (i == FRAG_NORMAL_STREAM && FRAG_GETCOUNT(fragid[i]) > MAX_NORMAL_FRAGMENTS)
return FALSE;
if (i == FRAG_FILE_STREAM && FRAG_GETCOUNT(fragid[i]) > MAX_FILE_FRAGMENTS)
return FALSE;
if (FRAG_GETID(fragid[i]) > FRAG_GETCOUNT(fragid[i]))
return FALSE;
if (!frag_length[i])
return FALSE;
if ((size_t)frag_length[i] > FRAGMENT_MAX_SIZE || (size_t)frag_offset[i] > NET_MAX_PAYLOAD - 1)
return FALSE;
int frag_end = frag_offset[i] + frag_length[i];
// end of fragment is out of the packet
if (frag_end + msg_readcount > net_message.cursize)
return FALSE;
// fragment overlaps next stream's fragment or placed after it
for (int j = i + 1; j < MAX_STREAMS; j++)
{
if (frag_end > frag_offset[j] && frag_message[j]) // don't add msg_readcount for comparison
return FALSE;
}
#endif // REHLDS_FIXES
}
return TRUE;
}
bool NetChannel::CheckForCompletion(int stream, int intotalbuffers)
{
int c;
int size;
int id;
fragbuf_t *p;
size = 0;
c = 0;
if (stream != FRAG_NORMAL_STREAM && stream != FRAG_FILE_STREAM) {
m_System->DPrintf("ERROR! NetChannel::CheckForCompletion: invalid stream number %i.\n");
return false;
}
p = m_incomingbufs[stream];
if (!p) {
return false;
}
while (p)
{
size += p->size;
c++;
id = FRAG_GETID(p->bufferId);
if (id != c)
{
m_System->DPrintf("WARNING! NetChannel::CheckForCompletion: lost/dropped fragment Lost/dropped fragment would cause stall, retrying connection\n");
m_crashed = true;
return false;
}
p = p->next;
}
// Received final message
if (c == intotalbuffers)
{
switch (stream)
{
case FRAG_NORMAL_STREAM:
CopyNormalFragments();
break;
case FRAG_FILE_STREAM:
m_System->Printf("TODO! NetChannel::CheckForCompletion: create file from fragments.\n");
break;
}
return true;
}
return false;
}
void Netchan_AddBufferToList(fragbuf_t **pplist, fragbuf_t *pbuf)
{
// Find best slot
fragbuf_t *pprev, *n;
int id1, id2;
pbuf->next = nullptr;
if (!pplist)
return;
if (!*pplist)
{
pbuf->next = *pplist;
*pplist = pbuf;
return;
}
pprev = *pplist;
while (pprev->next)
{
n = pprev->next; // Next item in list
id1 = FRAG_GETID(n->bufferid);
id2 = FRAG_GETID(pbuf->bufferid);
if (id1 > id2)
{
// Insert here
pbuf->next = n->next;
pprev->next = pbuf;
return;
}
pprev = pprev->next;
}
// Insert at end
pprev->next = pbuf;
}
void Netchan_CheckForCompletion(netchan_t *chan, int stream, int intotalbuffers)
{
int c;
int size;
int id;
fragbuf_t *p;
size = 0;
c = 0;
p = chan->incomingbufs[stream];
if (!p)
return;
while (p)
{
size += p->frag_message.cursize;
c++;
id = FRAG_GETID(p->bufferid);
if (id != c && chan == &g_pcls.netchan)
{
if (chan->sock == NS_MULTICAST)
{
char szCommand[32];
Q_snprintf(szCommand, sizeof(szCommand), "listen %s\n", NET_AdrToString(chan->remote_address));
Cbuf_AddText(szCommand);
return;
}
Con_Printf("%s: Lost/dropped fragment would cause stall, retrying connection\n", __func__);
Cbuf_AddText("retry\n");
}
p = p->next;
}
// Received final message
if (c == intotalbuffers)
{
chan->incomingready[stream] = true;
}
}
/*
==============================
Netchan_CheckForCompletion
==============================
*/
void Netchan_CheckForCompletion( netchan_t *chan, int stream, int intotalbuffers )
{
int c, id;
int size;
fragbuf_t *p;
size = 0;
c = 0;
p = chan->incomingbufs[stream];
if( !p ) return;
while( p )
{
size += BF_GetNumBytesWritten( &p->frag_message );
c++;
id = FRAG_GETID( p->bufferid );
if( id != c )
{
if( chan->sock == NS_CLIENT )
{
MsgDev( D_ERROR, "Lost/dropped fragment would cause stall, retrying connection\n" );
Cbuf_AddText( "reconnect\n" );
}
}
p = p->next;
}
// received final message
if( c == intotalbuffers )
{
chan->incomingready[stream] = true;
MsgDev( D_NOTE, "\nincoming is complete %i bytes waiting\n", size );
}
}
qboolean Netchan_Process(netchan_t *chan)
{
int i;
unsigned int sequence, sequence_ack;
unsigned int reliable_ack, reliable_message;
unsigned int fragid[MAX_STREAMS] = { 0, 0 };
qboolean frag_message[MAX_STREAMS] = { false, false };
int frag_offset[MAX_STREAMS] = { 0, 0 };
int frag_length[MAX_STREAMS] = { 0, 0 };
qboolean message_contains_fragments;
if (!g_pcls.demoplayback && !g_pcls.passive)
{
if (!NET_CompareAdr(net_from, chan->remote_address))
return FALSE;
}
chan->last_received = realtime;
// get sequence numbers
MSG_BeginReading();
sequence = MSG_ReadLong();
sequence_ack = MSG_ReadLong();
if (sequence_ack & 0x40000000)
{
if (!g_modfuncs.m_pfnProcessIncomingNet)
return FALSE;
}
if (g_modfuncs.m_pfnProcessIncomingNet)
{
if (!g_modfuncs.m_pfnProcessIncomingNet(chan, &net_message))
return FALSE;
}
reliable_message = sequence >> 31;
reliable_ack = sequence_ack >> 31;
message_contains_fragments = sequence & (1 << 30) ? true : false;
COM_UnMunge2(&net_message.data[8], net_message.cursize - 8, sequence & 0xFF);
if (message_contains_fragments)
{
for (i = 0; i < MAX_STREAMS; i++)
{
if (MSG_ReadByte())
{
frag_message[i] = true;
fragid[i] = MSG_ReadLong();
frag_offset[i] = MSG_ReadShort();
frag_length[i] = MSG_ReadShort();
}
}
if (!Netchan_Validate(chan, frag_message, fragid, frag_offset, frag_length))
return FALSE;
}
sequence &= ~(1 << 31);
sequence &= ~(1 << 30);
sequence_ack &= ~(1 << 31);
sequence_ack &= ~(1 << 30);
if (net_showpackets.value != 0.0 && net_showpackets.value != 3.0)
{
char c = (chan == &g_pcls.netchan) ? 'c' : 's';
Con_Printf(
" %c <-- sz=%i seq=%i ack=%i rel=%i tm=%f\n",
c,
net_message.cursize,
sequence,
sequence_ack,
reliable_message,
(chan == &g_pcls.netchan) ? g_pcl.time : g_psv.time);
}
if (sequence <= (unsigned)chan->incoming_sequence)
{
if (net_showdrop.value != 0.0) {
if (sequence == (unsigned)chan->incoming_sequence)
Con_Printf("%s:duplicate packet %i at %i\n", NET_AdrToString(chan->remote_address), sequence, chan->incoming_sequence);
else
Con_Printf("%s:out of order packet %i at %i\n", NET_AdrToString(chan->remote_address), sequence, chan->incoming_sequence);
}
return FALSE;
}
//
// dropped packets don't keep the message from being used
//
net_drop = sequence - (chan->incoming_sequence + 1);
if (net_drop > 0 && net_showdrop.value != 0.0)
{
Con_Printf("%s:Dropped %i packets at %i\n", NET_AdrToString(chan->remote_address), net_drop, sequence);
}
//
// if the current outgoing reliable message has been acknowledged
// clear the buffer to make way for the next
//
if (reliable_ack == (unsigned)chan->reliable_sequence)
{
// Make sure we actually could have ack'd this message
#ifdef REHLDS_FIXES
if (sequence_ack >= (unsigned)chan->last_reliable_sequence)
#else // REHLDS_FIXES
if (chan->incoming_acknowledged + 1 >= chan->last_reliable_sequence)
#endif // REHLDS_FIXES
{
chan->reliable_length = 0; // it has been received
}
}
//
// if this message contains a reliable message, bump incoming_reliable_sequence
//
chan->incoming_sequence = sequence;
chan->incoming_acknowledged = sequence_ack;
chan->incoming_reliable_acknowledged = reliable_ack;
if (reliable_message)
{
chan->incoming_reliable_sequence ^= 1;
}
int statId = chan->flow[FLOW_INCOMING].current & 0x1F;
chan->flow[FLOW_INCOMING].stats[statId].size = net_message.cursize + UDP_HEADER_SIZE;
chan->flow[FLOW_INCOMING].stats[statId].time = realtime;
chan->flow[FLOW_INCOMING].current++;
Netchan_UpdateFlow(chan);
if (message_contains_fragments)
{
for (i = 0; i < MAX_STREAMS; i++)
{
int j;
fragbuf_t *pbuf;
int inbufferid;
int intotalbuffers;
if (!frag_message[i])
continue;
inbufferid = FRAG_GETID(fragid[i]);
intotalbuffers = FRAG_GETCOUNT(fragid[i]);
if (fragid[i] != 0)
{
pbuf = Netchan_FindBufferById(&chan->incomingbufs[i], fragid[i], true);
if (pbuf) {
int len = frag_length[i];
SZ_Clear(&pbuf->frag_message);
SZ_Write(&pbuf->frag_message, &net_message.data[msg_readcount + frag_offset[i]], len);
}
else {
Con_Printf("Netchan_Process: Couldn't allocate or find buffer %i\n", inbufferid);
}
// Count # of incoming bufs we've queued? are we done?
Netchan_CheckForCompletion(chan, i, intotalbuffers);
}
// Rearrange incoming data to not have the frag stuff in the middle of it
int wpos = msg_readcount + frag_offset[i];
int rpos = wpos + frag_length[i];
Q_memmove(net_message.data + wpos, net_message.data + rpos, net_message.cursize - rpos);
net_message.cursize -= frag_length[i];
for (j = i + 1; j < MAX_STREAMS; j++)
{
frag_offset[j] -= frag_length[i]; // fragments order already validated
}
}
// Is there anything left to process?
if (net_message.cursize <= 16)
return FALSE;
}
return TRUE;
}
void NetChannel::ProcessIncoming(unsigned char *data, int size)
{
BitBuffer message(data, size);
int i;
unsigned int sequence, sequence_ack;
unsigned int reliable_ack, reliable_message;
unsigned int fragid[MAX_STREAMS] = { 0, 0 };
bool frag_message[MAX_STREAMS] = { false, false };
int frag_offset[MAX_STREAMS] = { 0, 0 };
int frag_length[MAX_STREAMS] = { 0, 0 };
bool message_contains_fragments;
int net_drop;
float newLoss;
float weight;
// get sequence numbers
sequence = message.ReadLong();
if (sequence == CONNECTIONLESS_HEADER)
{
NetPacket *p = new NetPacket;
p->connectionless = true;
p->time = m_System->GetTime();
p->seqnr = -1;
p->address.FromNetAddress(&m_remote_address);
p->data.Resize(size - 4);
p->data.WriteBuf(data + 4, size - 4);
p->data.Reset();
m_incomingPackets.AddHead(p);
return;
}
if (!m_connected) {
return;
}
sequence_ack = message.ReadLong();
COM_UnMunge2(message.GetData() + 8, size - 8, sequence & 0xFF);
reliable_message = sequence >> 31;
reliable_ack = sequence_ack >> 31;
message_contains_fragments = sequence & (1 << 30) ? true : false;
// TODO: Looks like need to move it above COM_UnMunge2
if (sequence_ack & 0x40000000)
{
m_crashed = true;
return;
}
if (message_contains_fragments)
{
for (i = 0; i < MAX_STREAMS; i++)
{
if (message.ReadByte())
{
frag_message[i] = true;
fragid[i] = message.ReadLong();
frag_offset[i] = message.ReadShort();
frag_length[i] = message.ReadShort();
}
}
}
sequence &= ~(1 << 31);
sequence &= ~(1 << 30);
sequence_ack &= ~(1 << 31);
sequence_ack &= ~(1 << 30);
if (sequence <= (unsigned int)m_incoming_sequence)
{
if (sequence == (unsigned int)m_incoming_sequence)
m_System->DPrintf("NetChannel::ProcessIncoming: duplicate packet %i at %i from %s\n", sequence, m_incoming_sequence, m_remote_address.ToString());
else
m_System->DPrintf("NetChannel::ProcessIncoming: out of order packet %i at %i from %s\n", sequence, m_incoming_sequence, m_remote_address.ToString());
return;
}
// dropped packets don't keep the message from being used
net_drop = sequence - (m_incoming_sequence + 1);
if (net_drop < 0) {
net_drop = 0;
}
newLoss = (net_drop + 1) * (1.0f / 200.0f);
if (newLoss < 1.0f)
{
weight = (float)net_drop / (float)(net_drop + 1);
m_loss = (1.0 - newLoss) * m_loss + weight * newLoss;
}
else
m_loss = 1;
// if the current outgoing reliable message has been acknowledged
// clear the buffer to make way for the next
if (reliable_ack == (unsigned int)m_reliable_sequence)
{
if (m_incoming_acknowledged + 1 >= m_last_reliable_sequence)
{
// it has been received
m_reliableOutSize = 0;
}
}
// if this message contains a reliable message, bump incoming_reliable_sequence
m_incoming_sequence = sequence;
m_incoming_acknowledged = sequence_ack;
m_incoming_reliable_acknowledged = reliable_ack;
if (reliable_message) {
m_incoming_reliable_sequence ^= 1u;
}
int statId = m_flow[FLOW_INCOMING].current & 0x1f;
m_flow[FLOW_INCOMING].stats[statId].size = size + UDP_HEADER_SIZE;
m_flow[FLOW_INCOMING].stats[statId].time = m_System->GetTime();
m_flow[FLOW_INCOMING].current++;
m_last_received = m_System->GetTime();
if (message_contains_fragments)
{
for (i = 0; i <= 1; ++i)
{
int j;
fragbuf_t *pbuf;
int inbufferid;
int intotalbuffers;
if (!frag_message[i])
continue;
inbufferid = FRAG_GETID(fragid[i]);
intotalbuffers = FRAG_GETCOUNT(fragid[i]);
if (fragid[i])
{
pbuf = FindBufferById(&m_incomingbufs[i], fragid[i], true);
if (pbuf)
{
memcpy(pbuf->data, message.GetData() + message.CurrentSize() + frag_offset[i], frag_length[i]);
pbuf->size = frag_length[i];
}
else
{
m_System->Printf("NetChannel::ProcessIncoming: couldn't allocate or find buffer %i\n", inbufferid);
}
// Count # of incoming bufs we've queued? are we done?
CheckForCompletion(i, intotalbuffers);
}
// Rearrange incoming data to not have the frag stuff in the middle of it
int wpos = message.CurrentSize() + frag_offset[i];
int rpos = wpos + frag_length[i];
memmove(message.GetData() + wpos, message.GetData() + rpos, message.GetMaxSize() - rpos);
message.m_MaxSize -= frag_length[i];
for (j = i + 1; j < MAX_STREAMS; j++)
{
// fragments order already validated
frag_offset[j] -= frag_length[i];
}
}
}
int curLen = message.GetMaxSize() - message.CurrentSize();
if (curLen > 0)
{
NetPacket *p = new NetPacket;
p->connectionless = 0;
p->hasReliableData = reliable_message != 0;
p->time = m_System->GetTime();
p->seqnr = m_incoming_sequence;
p->address.FromNetAddress(&m_remote_address);
p->data.Resize(curLen);
p->data.WriteBuf(message.m_CurByte, curLen);
p->data.Reset();
m_incomingPackets.AddHead(p);
}
}