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fteqw/engine/common/net_chan.c
2023-04-17 03:58:21 +01:00

1213 lines
33 KiB
C

/*
Copyright (C) 1996-1997 Id Software, Inc.
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 2
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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "quakedef.h"
#ifdef _WIN32
#include "winquake.h"
#else
#include "unistd.h"
#endif
#define PACKET_HEADER 8
#define ANTISTUNBIAS 0x40000000 //adding this to sequences in the header ensures that we our packets will not get confused for stun or rtp packets.
/*
packet header
-------------
31 sequence
1 does this message contain a reliable payload
31 acknowledge sequence
1 acknowledge receipt of even/odd message
16 qport (only from client)
15 fragoffset (extension)
1 lastfrag (extension)
The remote connection never knows if it missed a reliable message, the
local side detects that it has been dropped by seeing a sequence acknowledge
higher thatn the last reliable sequence, but without the correct even/odd
bit for the reliable set.
If the sender notices that a reliable message has been dropped, it will be
retransmitted. It will not be retransmitted again until a message after
the retransmit has been acknowledged and the reliable still failed to get there.
if the sequence number is -1, the packet should be handled without a netcon
The reliable message can be added to at any time by doing
MSG_Write* (&netchan->message, <data>).
If the message buffer is overflowed, either by a single message, or by
multiple frames worth piling up while the last reliable transmit goes
unacknowledged, the netchan signals a fatal error.
Reliable messages are always placed first in a packet, then the unreliable
message is included if there is sufficient room.
To the receiver, there is no distinction between the reliable and unreliable
parts of the message, they are just processed out as a single larger message.
Illogical packet sequence numbers cause the packet to be dropped, but do
not kill the connection. This, combined with the tight window of valid
reliable acknowledgement numbers provides protection against malicious
address spoofing.
The qport field is a workaround for bad address translating routers that
sometimes remap the client's source port on a packet during gameplay.
If the base part of the net address matches and the qport matches, then the
channel matches even if the IP port differs. The IP port should be updated
to the new value before sending out any replies.
fragmentation works like IP, offset and morefrags. offset is *8 (decode: (offset&~1)<<2 to avoid stomping on the morefrags flag, this allows really jumbo packets with 18 bits of length)
*/
int net_drop;
cvar_t showpackets = CVAR("showpackets", "0");
cvar_t showdrop = CVAR("showdrop", "0");
cvar_t qport = CVARF("qport_", "0", CVAR_NOSAVE);
#ifdef FTE_TARGET_WEB //with webrtc our packets will be layered over sctp(header=28,extras=20ish) over dtls(13),
cvar_t net_mtu = CVARD("net_mtu", "1384", "Specifies a maximum udp payload size, above which packets will be fragmented. If routers all worked properly this could be some massive value, and some massive value may work really nicely for lans. Use smaller values than the default if you're connecting through nested tunnels through routers that fail with IP fragmentation.");
#else
cvar_t net_mtu = CVARD("net_mtu", "1440", "Specifies a maximum udp payload size, above which packets will be fragmented. If routers all worked properly this could be some massive value, and some massive value may work really nicely for lans. Use smaller values than the default if you're connecting through nested tunnels through routers that fail with IP fragmentation.");
#endif
cvar_t net_compress = CVARD("net_compress", "0", "Enables huffman compression of network packets.");
cvar_t pext_vrinputs = CVARD("_pext_vrinputs", "0", "RENAME ME WHEN STABLE. Networks player inputs slightly differently, allowing for greater capabilities, particuarly vr controller info.");
cvar_t pext_lerptime = CVARD("_pext_lerptime", "0", "RENAME ME WHEN STABLE. Sends timing hints for interpolation.");
cvar_t pext_infoblobs = CVARD("_pext_infoblobs", "0", "RENAME ME WHEN STABLE. Enables the use of very large infokeys containing potentially invalid chars. Note that the userinfo is still limited by sv_userinfo_bytelimit and sv_userinfo_keylimit.");
cvar_t pext_replacementdeltas = CVARD("pext_replacementdeltas", "1", "Enables the use of alternative nack-based entity deltas");
cvar_t pext_predinfo = CVARD("pext_predinfo", "1", "Enables some extra things to support prediction over NQ protocols.");
#if defined(HAVE_CLIENT) && defined(HAVE_SERVER)
#define NET_SendPacket(c,s,d,t) NET_SendPacket(((c)!=NS_CLIENT)?svs.sockets:cls.sockets,s,d,t)
#elif defined(HAVE_SERVER)
#define NET_SendPacket(c,s,d,t) NET_SendPacket(svs.sockets,s,d,t)
#else
#define NET_SendPacket(c,s,d,t) NET_SendPacket(cls.sockets,s,d,t)
#endif
/*returns the entire bitmask of supported+enabled extensions*/
unsigned int Net_PextMask(unsigned int protover, qboolean fornq)
{
unsigned int mask = 0;
if (protover == PROTOCOL_VERSION_FTE1)
{
#ifdef PEXT_SCALE
mask |= PEXT_SCALE;
#endif
#ifdef PEXT_LIGHTSTYLECOL
mask |= PEXT_LIGHTSTYLECOL;
#endif
#ifdef PEXT_TRANS
mask |= PEXT_TRANS;
#endif
#ifdef PEXT_VIEW2
mask |= PEXT_VIEW2;
#endif
#ifdef PEXT_ACCURATETIMINGS
#ifdef QUAKESTATS //needs stat_time
mask |= PEXT_ACCURATETIMINGS;
#endif
#endif
#ifdef PEXT_ZLIBDL
mask |= PEXT_ZLIBDL;
#endif
#ifdef PEXT_FATNESS
mask |= PEXT_FATNESS;
#endif
#ifdef PEXT_HLBSP
mask |= PEXT_HLBSP;
#endif
#ifdef PEXT_Q2BSP
mask |= PEXT_Q2BSP;
#endif
#ifdef PEXT_Q3BSP
mask |= PEXT_Q3BSP;
#endif
#ifdef PEXT_TE_BULLET
mask |= PEXT_TE_BULLET;
#endif
#ifdef PEXT_HULLSIZE
mask |= PEXT_HULLSIZE;
#endif
#ifdef PEXT_SETVIEW
mask |= PEXT_SETVIEW;
#endif
#ifdef PEXT_MODELDBL
mask |= PEXT_MODELDBL;
#endif
#ifdef PEXT_SOUNDDBL
mask |= PEXT_SOUNDDBL;
#endif
#ifdef PEXT_VWEAP
mask |= PEXT_VWEAP;
#endif
#ifdef PEXT_FLOATCOORDS
mask |= PEXT_FLOATCOORDS;
#endif
mask |= PEXT_SPAWNSTATIC2;
mask |= PEXT_COLOURMOD;
#if MAX_SPLITS > 1
mask |= PEXT_SPLITSCREEN;
#endif
mask |= PEXT_HEXEN2;
mask |= PEXT_CUSTOMTEMPEFFECTS;
mask |= PEXT_256PACKETENTITIES;
mask |= PEXT_ENTITYDBL;
mask |= PEXT_ENTITYDBL2;
mask |= PEXT_SHOWPIC;
mask |= PEXT_SETATTACHMENT;
#ifdef PEXT_CHUNKEDDOWNLOADS
mask |= PEXT_CHUNKEDDOWNLOADS;
#endif
#ifdef CSQC_DAT
mask |= PEXT_CSQC;
#endif
#ifdef PEXT_DPFLAGS
mask |= PEXT_DPFLAGS;
#endif
if (fornq)
{
//only ones that are tested
mask &=
#ifdef CSQC_DAT
PEXT_CSQC |
#endif
#ifdef PEXT_Q2BSP
PEXT_Q2BSP |
#endif
#ifdef PEXT_Q3BSP
PEXT_Q3BSP |
#endif
PEXT_TE_BULLET | //qw's gunshot+explosions etc.
PEXT_FLOATCOORDS | PEXT_HLBSP;
//these all depend fully upon the player/entity deltas, and don't make sense for NQ. Implement PEXT2_REPLACEMENTDELTAS instead.
mask &= ~(PEXT_SCALE|PEXT_TRANS|PEXT_ACCURATETIMINGS|PEXT_FATNESS|PEXT_HULLSIZE|PEXT_MODELDBL|PEXT_ENTITYDBL|PEXT_ENTITYDBL2|PEXT_COLOURMOD|PEXT_SPAWNSTATIC2|PEXT_256PACKETENTITIES|PEXT_SETATTACHMENT|PEXT_DPFLAGS);
}
}
else if (protover == PROTOCOL_VERSION_FTE2)
{
mask |= PEXT2_PRYDONCURSOR;
#ifdef PEXT2_VOICECHAT
mask |= PEXT2_VOICECHAT;
#endif
mask |= PEXT2_SETANGLEDELTA;
if (pext_replacementdeltas.ival)
{
mask |= PEXT2_REPLACEMENTDELTAS;
if (/*fornq &&*/ pext_predinfo.ival)
mask |= PEXT2_PREDINFO;
}
if (pext_infoblobs.ival)
mask |= PEXT2_INFOBLOBS;
if (pext_vrinputs.ival)
mask |= PEXT2_VRINPUTS;
if (pext_lerptime.ival)
mask |= PEXT2_LERPTIME;
if (MAX_CLIENTS != QWMAX_CLIENTS)
mask |= PEXT2_MAXPLAYERS;
if (mask & PEXT2_REPLACEMENTDELTAS)
mask |= PEXT2_NEWSIZEENCODING; //use if we can
mask |= PEXT2_STUNAWARE;
if (fornq)
{
//only ones that are tested
mask &= PEXT2_PRYDONCURSOR | PEXT2_VOICECHAT | PEXT2_SETANGLEDELTA | PEXT2_REPLACEMENTDELTAS | PEXT2_MAXPLAYERS | PEXT2_PREDINFO | PEXT2_NEWSIZEENCODING | PEXT2_VRINPUTS | PEXT2_LERPTIME;
}
// else
// mask &= ~PEXT2_PREDINFO;
}
else if (protover == PROTOCOL_VERSION_EZQUAKE1)
{
mask = EZPEXT1_FLOATENTCOORDS;//|EZPEXT1_SETANGLEREASON;
if (fornq)
{
mask &= ~EZPEXT1_FLOATENTCOORDS; //keep things simple. interactions are not defined.
mask &= ~EZPEXT1_SETANGLEREASON; //potentially breaks too many nq mods. don't encourage it.
}
}
return mask;
}
/*
===============
Netchan_Init
===============
*/
void Netchan_Init (void)
{
static char qportstr[16];
int port;
// pick a port value that should be nice and random
#ifdef _WIN32
port = (time(NULL)) & 0xffff;
#elif defined(NACL)
port = ((int)(getpid()) * time(NULL)) & 0xffff;
#else
port = ((int)(getpid()+getuid()*1000) * time(NULL)) & 0xffff;
#endif
Q_snprintfz(qportstr, sizeof(qportstr), "%i", port);
qport.enginevalue = qportstr;
Cvar_Register (&pext_predinfo, "Protocol Extensions");
Cvar_Register (&pext_replacementdeltas, "Protocol Extensions");
Cvar_Register (&pext_infoblobs, "Protocol Extensions");
Cvar_Register (&pext_vrinputs, "Protocol Extensions");
Cvar_Register (&pext_lerptime, "Protocol Extensions");
Cvar_Register (&showpackets, "Networking");
Cvar_Register (&showdrop, "Networking");
Cvar_Register (&qport, "Networking");
Cvar_Register (&net_mtu, "Networking");
Cvar_Register (&net_compress, "Networking");
}
/*
===============
Netchan_OutOfBand
Sends an out-of-band datagram
================
*/
void Netchan_OutOfBand (netsrc_t sock, netadr_t *adr, int length, const qbyte *data)
{
sizebuf_t send;
qbyte send_buf[MAX_QWMSGLEN + PACKET_HEADER];
// write the packet header
memset(&send, 0, sizeof(send));
send.data = send_buf;
send.maxsize = sizeof(send_buf);
send.cursize = 0;
MSG_WriteLong (&send, -1); // -1 sequence means out of band
SZ_Write (&send, data, length);
// send the datagram
//zoid, no input in demo playback mode
#ifndef SERVERONLY
if (!cls.demoplayback)
#endif
NET_SendPacket (sock, send.cursize, send.data, adr);
}
/*
===============
Netchan_OutOfBandPrint
Sends a text message in an out-of-band datagram
================
*/
void VARGS Netchan_OutOfBandPrint (netsrc_t sock, netadr_t *adr, char *format, ...)
{
va_list argptr;
static char string[8192]; // ??? why static?
va_start (argptr, format);
vsnprintf (string,sizeof(string)-1, format,argptr);
va_end (argptr);
Netchan_OutOfBand (sock, adr, strlen(string), (qbyte *)string);
}
#ifndef CLIENTONLY
void VARGS Netchan_OutOfBandTPrintf (netsrc_t sock, netadr_t *adr, int language, translation_t text, ...)
{
va_list argptr;
static char string[8192]; // ??? why static?
const char *format = langtext(text, language);
string[0] = A2C_PRINT;
va_start (argptr, text);
vsnprintf (string+1,sizeof(string)-1, format,argptr);
va_end (argptr);
Netchan_OutOfBand (sock, adr, strlen(string), (qbyte *)string);
}
#endif
/*
==============
Netchan_Setup
called to open a channel to a remote system
==============
*/
void Netchan_Setup (netsrc_t sock, netchan_t *chan, netadr_t *adr, int qport)
{
memset (chan, 0, sizeof(*chan));
chan->sock = sock;
chan->remote_address = *adr;
chan->last_received = realtime;
#ifdef NQPROT
chan->nqreliable_allowed = true;
#endif
chan->incoming_unreliable = -1;
chan->message.data = chan->message_buf;
chan->message.allowoverflow = true;
chan->message.maxsize = MAX_QWMSGLEN;
chan->qport = qport;
chan->qportsize = 2;
}
/*
===============
Netchan_CanPacket
Returns true if the bandwidth choke isn't active
================
*/
#define MAX_BACKUP 200
qboolean Netchan_CanPacket (netchan_t *chan, int rate)
{
if (chan->remote_address.type == NA_LOOPBACK)
return true; //don't ever drop packets due to possible routing problems when there is no routing.
if (!rate)
return true;
if (chan->cleartime < realtime + 0.25)//(MAX_BACKUP/(float)rate))
return true;
return false;
}
int Netchan_CanBytes (netchan_t *chan, int rate)
{
const double slop = 0.25;
if (chan->remote_address.type == NA_LOOPBACK)
return 0x7fffffff; //don't ever drop packets due to possible routing problems when there is no routing.
if (!rate)
return 0x7fffffff;
return ((realtime+slop)-chan->cleartime)*rate;
}
void Netchan_Block (netchan_t *chan, int bytes, int rate)
{
if (rate)
{
if (chan->cleartime < realtime-0.25) //0.25 allows it to be a little bursty.
chan->cleartime = realtime + (bytes/(float)rate);
else
chan->cleartime += bytes/(float)rate;
}
}
/*
===============
Netchan_CanReliable
Returns true if the bandwidth choke isn't
================
*/
qboolean Netchan_CanReliable (netchan_t *chan, int rate)
{
if (chan->reliable_length)
return false; // waiting for ack
return Netchan_CanPacket (chan, rate);
}
#ifdef SERVERONLY
qboolean ServerPaused(void);
#endif
#ifdef NQPROT
size_t ZLib_DecompressBuffer(qbyte *in, size_t insize, qbyte *out, size_t maxoutsize);
enum nqnc_packettype_e NQNetChan_Process(netchan_t *chan)
{
int header;
int sequence;
int drop;
chan->bytesin += net_message.cursize;
MSG_BeginReading (&net_message, chan->netprim);
header = LongSwap(MSG_ReadLong());
if (header & NETFLAG_CTL)
return NQNC_IGNORED; //huh?
#ifdef HAVE_CLIENT
if (header & NETFLAG_ZLIB)
{ //note: qex gets the size header wrong here.
qbyte *tmp;
if (net_message.cursize <= PACKET_HEADER || net_message.cursize != PACKET_HEADER+(header & NETFLAG_LENGTH_MASK))
return NQNC_IGNORED; //huh?
/*redundantsequence =*/ MSG_ReadLong(); //wasting 4 bytes...
#ifdef AVAIL_ZLIB
tmp = alloca(0xffff);
//note: its zlib rather than raw deflate (wasting a further 6 bytes...).
net_message.cursize = ZLib_DecompressBuffer(net_message.data+8, net_message.cursize-8, tmp, 0xffff);
if (net_message.cursize < PACKET_HEADER)
#endif
{
if (chan->sock == NS_CLIENT)
{ //clients can just throw an error. the server will appear dead if we try to just ignore it.
Host_EndGame("QuakeEx netchan decompression error");
return NQNC_IGNORED;
}
else
{ //inject a disconnect request. clients shouldn't be sending this anyway.
net_message.data[8] = clc_disconnect;
net_message.cursize = 9;
return NQNC_RELIABLE;
}
}
memcpy(net_message.data, tmp, net_message.cursize);
MSG_BeginReading (&net_message, chan->netprim);
header = LongSwap(MSG_ReadLong()); //re-read the now-decompressed copy of the header for the real flags
}
#endif
if (net_message.cursize != (header & NETFLAG_LENGTH_MASK))
return NQNC_IGNORED; //size was wrong, couldn't have been ours.
sequence = LongSwap(MSG_ReadLong());
if (header & NETFLAG_ACK)
{
if (sequence == chan->reliable_sequence)
{
chan->reliable_start += MAX_NQDATAGRAM;
if (chan->reliable_start >= chan->reliable_length)
{
chan->reliable_length = 0; //they got the entire message
chan->reliable_start = 0;
}
chan->incoming_reliable_acknowledged = chan->reliable_sequence;
chan->reliable_sequence++;
chan->nqreliable_allowed = true;
chan->last_received = realtime;
}
else if (sequence < chan->reliable_sequence)
{
if (showdrop.ival)
Con_Printf("Stale ack recieved\n");
}
else if (sequence > chan->reliable_sequence)
{
if (showdrop.ival)
Con_Printf("Future ack recieved\n");
}
if (showpackets.value)
Con_Printf ("in %s a=%i %i\n"
, chan->sock != NS_SERVER?"s2c":"c2s"
, sequence
, 0);
return NQNC_ACK; //don't try execing the 'payload'. I hate ack packets.
}
if (header & NETFLAG_UNRELIABLE)
{
if (sequence <= chan->incoming_unreliable)
{
if (showdrop.ival)
Con_Printf("Stale datagram recieved (%i<=%i)\n", sequence, chan->incoming_unreliable);
return NQNC_IGNORED;
}
drop = sequence - chan->incoming_unreliable - 1;
if (drop > 0)
{
if (showdrop.ival)
Con_Printf("Dropped %i datagrams (%i - %i)\n", drop, chan->incoming_unreliable+1, sequence-1);
chan->drop_count += drop;
}
chan->incoming_unreliable = sequence;
// chan->frame_latency = chan->frame_latency*OLD_AVG
// + (chan->outgoing_sequence-sequence_ack)*(1.0-OLD_AVG);
chan->frame_rate = chan->frame_rate*OLD_AVG
+ (realtime-chan->last_received)*(1.0-OLD_AVG);
chan->last_received = realtime;
chan->incoming_acknowledged++;
chan->good_count++;
if (showpackets.value)
Con_Printf ("in %s u=%i %i\n"
, chan->sock != NS_SERVER?"s2c":"c2s"
, chan->incoming_unreliable
, net_message.cursize);
return NQNC_UNRELIABLE;
}
if (header & NETFLAG_DATA)
{
int runt[2];
//always reply. a stale sequence probably means our ack got lost.
runt[0] = BigLong(NETFLAG_ACK | 8);
runt[1] = BigLong(sequence);
NET_SendPacket (chan->sock, 8, runt, &net_from);
if (showpackets.value)
Con_Printf ("out %s a=%i %i\n"
, chan->sock == NS_SERVER?"s2c":"c2s"
, sequence
, 0);
chan->last_received = realtime;
if (sequence == chan->incoming_reliable_sequence)
{
chan->incoming_reliable_sequence++;
if (chan->in_fragment_length + net_message.cursize-8 >= sizeof(chan->in_fragment_buf))
{
chan->fatal_error = true;
return NQNC_IGNORED;
}
memcpy(chan->in_fragment_buf + chan->in_fragment_length, net_message.data+8, net_message.cursize-8);
chan->in_fragment_length += net_message.cursize-8;
if (header & NETFLAG_EOM)
{
SZ_Clear(&net_message);
SZ_Write(&net_message, chan->in_fragment_buf, chan->in_fragment_length);
chan->in_fragment_length = 0;
MSG_BeginReading(&net_message, chan->netprim);
if (showpackets.value)
Con_Printf ("in %s r=%i %i\n"
, chan->sock != NS_SERVER?"s2c":"c2s"
, sequence
, net_message.cursize);
return NQNC_RELIABLE; //we can read it now
}
}
else
{
if (showdrop.ival)
Con_Printf("Stale reliable (%i)\n", sequence);
}
return NQNC_IGNORED;
}
return NQNC_IGNORED; //not supported.
}
#endif
/*
===============
Netchan_Transmit
tries to send an unreliable message to a connection, and handles the
transmition / retransmition of the reliable messages.
A 0 length will still generate a packet and deal with the reliable messages.
================
*/
int Netchan_Transmit (netchan_t *chan, int length, qbyte *data, int rate)
{
sizebuf_t send;
qbyte send_buf[MAX_OVERALLMSGLEN + PACKET_HEADER];
qboolean send_reliable;
char remote_adr[MAX_ADR_SIZE];
unsigned w1, w2;
int i;
neterr_t e;
int dupes = chan->dupe;
int availbytes = Netchan_CanBytes(chan, rate);
availbytes = max(0, availbytes); //make sure it can't go negative (clientside doesn't check rate limits much)
#ifdef NQPROT
if (chan->isnqprotocol)
{
int sentsize = 0;
send.data = send_buf;
send.maxsize = MAX_NQMSGLEN + PACKET_HEADER;
send.cursize = 0;
/*unreliables flood out, but reliables are tied to server sequences*/
if (chan->nqreliable_resendtime < realtime)
chan->nqreliable_allowed = true;
if (chan->nqreliable_allowed)
{
//consume the new reliable when we can.
if (!chan->reliable_length && chan->message.cursize && chan->nqunreliableonly != 1)
{
if (chan->nqunreliableonly == 2)
chan->nqunreliableonly = 1;
memcpy (chan->reliable_buf, chan->message_buf, chan->message.cursize);
chan->reliable_length = chan->message.cursize;
chan->reliable_start = 0;
chan->message.cursize = 0;
}
i = chan->reliable_length - chan->reliable_start;
if (i>0)
{
MSG_WriteLong(&send, 0);
MSG_WriteLong(&send, LongSwap(chan->reliable_sequence));
//limit the payload length to nq's datagram max size.
//relax the limitation if its reliable (ie: over tcp) where its assumed to have no real limit
if (i > MAX_NQDATAGRAM && !NET_AddrIsReliable(&chan->remote_address))
i = MAX_NQDATAGRAM;
SZ_Write (&send, chan->reliable_buf+chan->reliable_start, i);
if (chan->reliable_start+i == chan->reliable_length)
{
if (send.cursize + length < send.maxsize)
{ //throw the unreliable packet into the same one as the reliable (but not sent reliably)
// SZ_Write (&send, data, length);
// length = 0;
}
*(int*)send_buf = BigLong(NETFLAG_DATA | NETFLAG_EOM | send.cursize);
}
else
*(int*)send_buf = BigLong(NETFLAG_DATA | send.cursize);
chan->bytesout += send.cursize;
sentsize += send.cursize;
if (showpackets.value)
Con_Printf ("out %s r s=%i %i\n"
, chan->sock == NS_SERVER?"s2c":"c2s"
, chan->reliable_sequence
, send.cursize);
chan->nqreliable_allowed = false;
chan->nqreliable_resendtime = realtime + 0.3; //resend reliables after 0.3 seconds. nq transports suck.
if (NET_SendPacket (chan->sock, send.cursize, send.data, &chan->remote_address) == NETERR_SENT && (
NET_AddrIsReliable(&chan->remote_address) || chan->nqunreliableonly==3 ))
{ //if over tcp (or we're dropping the connection), everything is assumed to be reliable. pretend it got acked now.
//if we get an ack later, then who cares.
chan->reliable_start += i;
if (chan->reliable_start >= chan->reliable_length)
{
chan->reliable_length = 0; //they got the entire message
chan->reliable_start = 0;
}
chan->incoming_reliable_acknowledged = chan->reliable_sequence;
chan->reliable_sequence++;
chan->nqreliable_allowed = true;
}
send.cursize = 0;
}
}
//send out the unreliable (if still unsent)
if (length)
{
MSG_WriteLong(&send, 0);
MSG_WriteLong(&send, LongSwap(chan->outgoing_unreliable));
chan->outgoing_unreliable++;
SZ_Write (&send, data, length);
*(int*)send_buf = BigLong(NETFLAG_UNRELIABLE | send.cursize);
for (i = -1, e = NETERR_SENT; i < dupes && e == NETERR_SENT; i++)
e = NET_SendPacket (chan->sock, send.cursize, send.data, &chan->remote_address);
sentsize += send.cursize*i;
if (e == NETERR_MTU && chan->mtu > 560)
{
Con_Printf("Reducing MSS to %i\n", chan->mtu);
chan->mtu -= 10;
}
if (showpackets.value)
Con_Printf ("out %s u=%i %i\n"
, chan->sock == NS_SERVER?"s2c":"c2s"
, chan->outgoing_unreliable-1
, send.cursize);
send.cursize = 0;
}
chan->bytesout += sentsize;
Netchan_Block(chan, sentsize, rate);
return sentsize;
}
#endif
// check for message overflow
if (chan->message.overflowed)
{
chan->fatal_error = true;
Con_TPrintf ("%s: Outgoing message overflow\n"
, NET_AdrToString (remote_adr, sizeof(remote_adr), &chan->remote_address));
return 0;
}
// if the remote side dropped the last reliable message, resend it
send_reliable = false;
if (chan->incoming_acknowledged > chan->last_reliable_sequence
&& chan->incoming_reliable_acknowledged != chan->reliable_sequence)
send_reliable = true;
// if the reliable transmit buffer is empty, copy the current message out
if (!chan->reliable_length && chan->message.cursize)
{
memcpy (chan->reliable_buf, chan->message_buf, chan->message.cursize);
chan->reliable_length = chan->message.cursize;
chan->message.cursize = 0;
chan->reliable_sequence ^= 1;
send_reliable = true;
}
// write the packet header
send.data = send_buf;
send.maxsize = (chan->mtu?chan->mtu:MAX_QWMSGLEN) + PACKET_HEADER;
send.cursize = 0;
w1 = chan->outgoing_sequence | (send_reliable<<31);
w2 = chan->incoming_sequence | (chan->incoming_reliable_sequence<<31);
if (chan->pext_stunaware)
{
w1 = BigLong(w1+ANTISTUNBIAS);
w2 = BigLong(w2);
}
chan->outgoing_sequence++;
MSG_WriteLong (&send, w1);
MSG_WriteLong (&send, w2);
// send the qport if we are a client
#ifndef SERVERONLY
if (chan->sock == NS_CLIENT)
{
if (chan->qportsize == 2)
MSG_WriteShort (&send, chan->qport);
else if (chan->qportsize == 1)
MSG_WriteByte (&send, chan->qport&0xff);
}
#endif
if (chan->pext_fragmentation)
{
//allow the max size to be bigger, sending everything available
send.maxsize = MAX_OVERALLMSGLEN + PACKET_HEADER;
MSG_WriteShort(&send, 0);
}
// copy the reliable message to the packet first
if (send_reliable)
{
if (send.maxsize - send.cursize < chan->reliable_length)
{
if (!chan->fatal_error)
{
chan->fatal_error = true;
Con_TPrintf ("%s: Path MTU is lower than %u\n"
, NET_AdrToString (remote_adr, sizeof(remote_adr), &chan->remote_address), chan->reliable_length);
}
chan->outgoing_sequence--;
return 0;
}
SZ_Write (&send, chan->reliable_buf, chan->reliable_length);
chan->last_reliable_sequence = chan->outgoing_sequence;
}
// add the unreliable part if space is available
if (send.maxsize - send.cursize >= length)
SZ_Write (&send, data, length);
// send the datagram
i = chan->outgoing_sequence & (MAX_LATENT-1);
chan->outgoing_size[i] = send.cursize;
chan->outgoing_time[i] = realtime;
#ifdef HUFFNETWORK
if (chan->compresstable)
{
//int oldsize = send.cursize;
Huff_CompressPacket(chan->compresstable, &send, 8 + ((chan->sock == NS_CLIENT)?2:0) + (chan->pext_fragmentation?2:0));
// Con_Printf("%i becomes %i\n", oldsize, send.cursize);
// Huff_DecompressPacket(&send, (chan->sock == NS_CLIENT)?10:8);
}
#endif
e = NETERR_SENT;
//zoid, no input in demo playback mode
#ifndef SERVERONLY
if (!cls.demoplayback)
#endif
{
int hsz = 10 + ((chan->sock == NS_CLIENT)?chan->qportsize:0); /*header size, if fragmentation is in use*/
dupes = min(chan->dupe, availbytes / send.cursize);
if ((!chan->pext_fragmentation))// || send.cursize < ((chan->mtu - hsz)&~7))
{ //vanilla sends
for (i = -1; i < dupes && e == NETERR_SENT; i++)
e = NET_SendPacket (chan->sock, send.cursize, send.data, &chan->remote_address);
send.cursize += send.cursize * i;
//ipv4 'guarentees' mtu sizes of at least 560ish.
//our reliable/backbuf messages are limited to 1024 bytes.
//this means that large reliables may be unsendable.
if (e == NETERR_MTU && chan->mtu > 560)
{
Con_Printf("Reducing MSS to %i\n", chan->mtu);
chan->mtu -= 10;
}
}
else
{ //fte's fragmentaton protocol
int offset = 0, no;
qboolean more;
int outbytes = 0;
int fragbytes;
/*FIXME: splurge over a number of frames, if we have an outgoing reliable*/
/*send the additional parts, adding new headers within the previous packet*/
do
{
no = offset + chan->mtu - hsz;
if (no < send.cursize-hsz)
{
no &= ~7;
more = true;
}
else
{
no = send.cursize-hsz;
more = false;
}
*(int*)&send.data[(offset) + 0] = LittleLong(w1);
*(int*)&send.data[(offset) + 4] = LittleLong(w2);
#ifndef SERVERONLY
if (chan->sock == NS_CLIENT)
{
if (chan->qportsize == 2)
*(short*)&send.data[offset + hsz-4] = LittleShort(chan->qport);
else if (chan->qportsize == 1)
*(qbyte*)&send.data[offset + hsz-3] = chan->qport&0xff;
}
#endif
*(short*)&send.data[offset + hsz-2] = LittleShort((offset>>2) | (more?1:0));
if (e == NETERR_SENT)
{
for (i = -1; i < dupes && e == NETERR_SENT; i++)
{
fragbytes = (no - offset) + hsz;
e = NET_SendPacket (chan->sock, fragbytes, send.data + offset, &chan->remote_address);
outbytes += fragbytes;
if (e == NETERR_MTU && !offset && chan->mtu > 560)
{
chan->mtu -= 16;
Con_Printf("Reducing MSS to %i\n", chan->mtu);
no = offset;
more = true;
break;
}
}
}
offset = no;
} while(more);
send.cursize = outbytes;
}
}
if (e == NETERR_SENT)
{
chan->bytesout += send.cursize;
Netchan_Block(chan, send.cursize, rate);
}
#ifdef SERVERONLY
if (ServerPaused())
chan->cleartime = realtime;
#endif
if (showpackets.value)
{
char *errtext;
switch(e)
{
case NETERR_SENT: errtext = ""; break;
case NETERR_NOROUTE: errtext = " unroutable"; break;
case NETERR_DISCONNECTED: errtext = " disconnected"; break;
case NETERR_MTU: errtext = " mss exceeded"; break;
case NETERR_CLOGGED: errtext = " conjestion"; break;
default: errtext = " unk error"; break;
}
Con_Printf ("%f %s --> s=%i(%i) a=%i(%i) %i%s\n"
, Sys_DoubleTime()
, chan->sock == NS_SERVER?"s2c":"c2s"
, chan->outgoing_sequence
, send_reliable
, chan->incoming_sequence
, chan->incoming_reliable_sequence
, send.cursize,
errtext);
}
return send.cursize;
}
/*
=================
Netchan_Process
called when the current net_message is from remote_address
modifies net_message so that it points to the packet payload
=================
*/
qboolean Netchan_Process (netchan_t *chan)
{
unsigned sequence, sequence_ack;
unsigned reliable_ack, reliable_message;
char adr[MAX_ADR_SIZE];
int offset;
if (
#ifndef SERVERONLY
!cls.demoplayback &&
#endif
!NET_CompareAdr (&net_from, &chan->remote_address))
return false;
chan->bytesin += net_message.cursize;
// get sequence numbers
MSG_BeginReading (&net_message, chan->netprim);
sequence = MSG_ReadLong ();
sequence_ack = MSG_ReadLong ();
if (chan->pext_stunaware)
{
sequence = BigLong(sequence);
if (!(sequence&ANTISTUNBIAS))
return false;
sequence -= ANTISTUNBIAS;
sequence_ack = BigLong(sequence_ack);
}
// skip over the qport if we are a server (its handled elsewhere)
#ifndef CLIENTONLY
if (chan->sock == NS_SERVER)
MSG_ReadShort ();
#endif
if (chan->pext_fragmentation)
offset = (unsigned short)MSG_ReadShort();
else
offset = 0;
reliable_message = sequence >> 31;
reliable_ack = sequence_ack >> 31;
sequence &= ~(1u<<31);
sequence_ack &= ~(1u<<31);
if (showpackets.value)
Con_Printf ("%f %s <-- s=%i(%i) a=%i(%i) %i%s\n"
, Sys_DoubleTime()
, chan->sock == NS_SERVER?"c2s":"s2c"
, sequence
, reliable_message
, sequence_ack
, reliable_ack
, net_message.cursize
, offset?" frag":"");
// get a rate estimation
#if 0
if (chan->outgoing_sequence - sequence_ack < MAX_LATENT)
{
int i;
double time, rate;
i = sequence_ack & (MAX_LATENT - 1);
time = realtime - chan->outgoing_time[i];
time -= 0.1; // subtract 100 ms
if (time <= 0)
{ // gotta be a digital link for <100 ms ping
if (chan->rate > 1.0/5000)
chan->rate = 1.0/5000;
}
else
{
if (chan->outgoing_size[i] < 512)
{ // only deal with small messages
rate = chan->outgoing_size[i]/time;
if (rate > 5000)
rate = 5000;
rate = 1.0/rate;
if (chan->rate > rate)
chan->rate = rate;
}
}
}
#endif
//
// discard stale or duplicated packets
//
if (sequence <= (unsigned)chan->incoming_sequence)
{
if (showdrop.value)
Con_TPrintf ("%s:Out of order packet %i at %i\n"
, NET_AdrToString (adr, sizeof(adr), &chan->remote_address)
, sequence
, chan->incoming_sequence);
return false;
}
if (offset)
{
int len = net_message.cursize - MSG_GetReadCount();
qboolean more = false;
if (offset & 1)
{
more = true;
offset &= ~1;
}
offset = offset << 2;
if (offset + len > sizeof(chan->in_fragment_buf)) /*stop the overflow*/
{
if (showdrop.value)
Con_Printf("Dropping packet - too many fragments\n");
return false;
}
if (chan->incoming_unreliable != sequence)
{
if (chan->in_fragment_length && showdrop.ival)
Con_Printf("final fragment lost (%i). dropping entire packet\n", offset);
/*sequence doesn't match, forget the old*/
chan->in_fragment_length = 0;
chan->incoming_unreliable = sequence;
}
if (offset != chan->in_fragment_length)
{
if (showdrop.ival)
Con_Printf("prior fragment lost (%i-%i). dropping entire packet\n", offset, chan->in_fragment_length);
return false; /*dropped one*/
}
memcpy(chan->in_fragment_buf + offset, net_message.data + MSG_GetReadCount(), len);
chan->in_fragment_length += len;
if (more)
{
/*nothing to process yet*/
return false;
}
memcpy(net_message.data, chan->in_fragment_buf, chan->in_fragment_length);
net_message.currentbit = 0;
net_message.cursize = chan->in_fragment_length;
if (showpackets.value)
Con_Printf ("<-- s=%i(%i) a=%i(%i) %i Recombined\n"
, sequence
, reliable_message
, sequence_ack
, reliable_ack
, net_message.cursize);
chan->incoming_unreliable = 0;
chan->in_fragment_length = 0;
}
else
{
/*kill any pending reliable*/
chan->incoming_unreliable = 0;
chan->in_fragment_length = 0;
}
//
// dropped packets don't keep the message from being used
//
net_drop = sequence - (chan->incoming_sequence+1);
if (net_drop > 0)
{
chan->drop_count += 1;
if (showdrop.value)
Con_TPrintf ("%s:Dropped %i packets at %i\n"
, NET_AdrToString (adr, sizeof(adr), &chan->remote_address)
, sequence-(chan->incoming_sequence+1)
, 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)
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;
//
// the message can now be read from the current message pointer
// update statistics counters
//
chan->frame_latency = chan->frame_latency*OLD_AVG
+ (chan->outgoing_sequence-sequence_ack)*(1.0-OLD_AVG);
chan->frame_rate = chan->frame_rate*OLD_AVG
+ (realtime-chan->last_received)*(1.0-OLD_AVG);
chan->good_count += 1;
chan->last_received = realtime;
#ifdef HUFFNETWORK
if (chan->compresstable)
{
// Huff_CompressPacket(&net_message, (chan->sock == NS_SERVER)?10:8);
Huff_DecompressPacket(chan->compresstable, &net_message, MSG_GetReadCount());
}
#endif
return true;
}