ref: a3500266c93417a33976c19525dbc5fb010ccecb
dir: /udp.c/
#include <u.h>
#include <libc.h>
#include <stdio.h>
#include <thread.h>
#include <bio.h>
#include <ndb.h>
#include <ip.h>
#include "dat.h"
#include "fns.h"
/* FIXME: this shit SUCKS, and ipv4 only because of other code */
extern Channel *fuckchan, *tchan;
static cvar_t *svport; /* server port and copy of string value */
static char srv[6];
static cvar_t *clport; /* "client" port and copy */
static char clsrv[6];
typedef struct Loopmsg Loopmsg;
typedef struct Loopback Loopback;
typedef struct Conmsg Conmsg;
typedef struct Conlist Conlist;
enum{
Hdrsz = 16+16+16+2+2, /* sizeof Udphdr w/o padding */
Bufsz = MAX_MSGLEN,
Nbuf = 64,
MAX_LOOPBACK = 4,
CLPORT = 27909
};
struct Loopmsg{
byte data[MAX_MSGLEN];
int datalen;
};
struct Loopback{
Loopmsg msgs[MAX_LOOPBACK];
int get;
int send;
};
static Loopback loopbacks[2];
struct Conlist{
Conlist *p;
uchar u[IPaddrlen+2];
char addr[IPaddrlen*2+8+6]; /* ipv6 + separators + port in decimal */
int dfd;
Udphdr h;
int src; /* q2 assumes broadcast replies are received on NS_CLIENT */
};
static Conlist *cnroot;
struct Conmsg{
Conlist *p;
int n;
uchar buf[Bufsz];
};
static Channel *udpchan, *clchan;
static netadr_t laddr; /* 0.0.0.0:0 */
static int cfd = -1, ufd = -1, clfd = -1, cldfd = -1;
static QLock cnlock;
qboolean
NET_CompareAdr(netadr_t a, netadr_t b)
{
return(a.ip[0] == b.ip[0] && a.ip[1] == b.ip[1] && a.ip[2] == b.ip[2] && a.ip[3] == b.ip[3] && a.port == b.port);
}
/* compares without the port */
qboolean
NET_CompareBaseAdr(netadr_t a, netadr_t b)
{
if(a.type != b.type)
return false;
switch(a.type){
case NA_LOOPBACK:
return true;
case NA_IP:
return (a.ip[0] == b.ip[0] && a.ip[1] == b.ip[1] && a.ip[2] == b.ip[2] && a.ip[3] == b.ip[3]);
case NA_IPX:
return !memcmp(a.ipx, b.ipx, 10);
default:
return false;
}
}
char *
NET_AdrToString(netadr_t a)
{
static char s[256];
seprint(s, s+sizeof s, "%ud.%ud.%ud.%ud:%hud", a.ip[0], a.ip[1], a.ip[2], a.ip[3], BigShort(a.port));
return s;
}
char *
NET_BaseAdrToString(netadr_t a)
{
static char s[256];
seprint(s, s+sizeof s, "%ud.%ud.%ud.%ud", a.ip[0], a.ip[1], a.ip[2], a.ip[3]);
return s;
}
static void
getip(char *a, int len)
{
int fd, n;
char buf[128], *f[3];
if((fd = open("/net/cs", ORDWR)) < 0)
sysfatal("open: %r");
snprint(buf, sizeof buf, "udp!%s!0", a);
n = strlen(buf);
if(write(fd, buf, n) != n)
sysfatal("translating %s: %r", a);
seek(fd, 0, 0);
if((n = read(fd, buf, sizeof(buf)-1)) <= 0)
sysfatal("reading cs tables: %r");
buf[n] = 0;
close(fd);
if(getfields(buf, f, 3, 1, " !") < 2)
sysfatal("bad cs entry %s", buf);
strncpy(a, f[1], len);
}
/*
=============
NET_StringToAdr
localhost
idnewt
idnewt:28000
192.246.40.70
192.246.40.70:28000
=============
*/
qboolean
NET_StringToAdr(char *addr, netadr_t *a) /* assumes IPv4 */
{
int i;
char s[256], *p, *pp;
if(!strcmp(addr, "localhost")){
memset(a, 0, sizeof *a);
a->type = NA_LOOPBACK;
return true;
}
strncpy(s, addr, sizeof s);
s[sizeof(s)-1] = 0;
/* FIXME: arbitrary length strings */
if((p = strrchr(s, ':')) != nil){
*p++ = '\0';
a->port = BigShort(atoi(p));
}
getip(s, sizeof(s)-1);
/* FIXMEGASHIT */
for(i = 0, pp = s; i < IPv4addrlen; i++){
if((p = strchr(pp, '.')) != nil)
*p++ = '\0';
a->ip[i] = atoi(pp);
pp = p;
}
a->type = NA_IP;
return true;
}
qboolean
NET_IsLocalAddress(netadr_t adr)
{
return NET_CompareAdr(adr, laddr);
}
static int
looprecv(netsrc_t sock, netadr_t *net_from, sizebuf_t *d)
{
int i;
Loopback *l;
l = &loopbacks[sock];
if(l->send - l->get > MAX_LOOPBACK)
l->get = l->send - MAX_LOOPBACK;
if(l->get >= l->send)
return 0;
i = l->get & (MAX_LOOPBACK-1);
l->get++;
memcpy(d->data, l->msgs[i].data, l->msgs[i].datalen);
d->cursize = l->msgs[i].datalen;
*net_from = laddr;
return 1;
}
static void
loopsend(netsrc_t sock, int length, void *data, netadr_t /*to*/)
{
Loopback *l;
int i;
l = &loopbacks[sock^1];
i = l->send & (MAX_LOOPBACK-1);
l->send++;
memcpy(l->msgs[i].data, data, length);
l->msgs[i].datalen = length;
}
static void
cninit(void)
{
if(cnroot != nil)
return;
if((cnroot = malloc(sizeof *cnroot)) == nil)
sysfatal("cninit:malloc: %r");
cnroot->p = cnroot;
memset(cnroot->u, 0, sizeof cnroot->u);
memset(cnroot->addr, 0, sizeof cnroot->addr);
cnroot->dfd = -1;
}
static Conlist *
cnins(int fd, char *addr, uchar *u, Udphdr *h, int src)
{
Conlist *p, *l;
l = cnroot;
if((p = malloc(sizeof *p)) == nil)
sysfatal("cnins:malloc: %r");
strncpy(p->addr, addr, sizeof p->addr);
memcpy(p->u, u, sizeof p->u);
p->dfd = fd;
if(h != nil)
memcpy(&p->h, h, sizeof p->h);
p->src = src;
p->p = l->p;
l->p = p;
return p;
}
static Conlist *
cnfind(char *raddr)
{
Conlist *p = cnroot->p;
while(p != cnroot){
if(!strncmp(p->addr, raddr, strlen(p->addr)))
return p;
p = p->p;
}
return nil;
}
static void
cndel(Conlist *p)
{
Conlist *l = cnroot;
while(l->p != p){
l = l->p;
if(l == cnroot)
sysfatal("cndel: bad unlink: cnroot 0x%p node 0x%p\n", cnroot, p);
}
l->p = p->p;
if(p->dfd != ufd && p->dfd != cldfd && p->dfd != -1)
close(p->dfd);
free(p);
}
static void
cnnuke(void)
{
Conlist *p, *l = cnroot;
if(cnroot == nil)
return;
do{
p = l;
l = l->p;
if(p->dfd != -1)
close(p->dfd);
free(p);
}while(l != cnroot);
cnroot = nil;
}
static void
dproc(void *me)
{
int n, fd;
Conmsg m;
Conlist *p;
Channel *c;
threadsetgrp(THnet);
m.p = p = me;
c = p->src == NS_CLIENT ? clchan : udpchan;
fd = p->dfd;
for(;;){
if((n = read(fd, m.buf, sizeof m.buf)) <= 0)
break;
m.n = n;
if(send(c, &m) < 0 || nbsend(fuckchan, nil) < 0){
fprint(2, "dproc: %r");
break;
}
}
cndel(me);
}
static void
uproc(void *c)
{
int n, fd;
uchar udpbuf[Bufsz+Hdrsz], u[IPaddrlen+2];
char a[IPaddrlen*2+8+6];
Udphdr h;
Conmsg m;
Conlist *p;
threadsetgrp(THnet);
fd = ufd;
if(c == clchan)
fd = cldfd;
for(;;){
if((n = read(fd, udpbuf, sizeof udpbuf)) <= 0)
break;
memcpy(&h, udpbuf, Hdrsz);
memcpy(u, h.raddr, IPaddrlen);
memcpy(u+IPaddrlen, h.rport, 2);
snprint(a, sizeof a, "%ud.%ud.%ud.%ud:%hud", u[12], u[13], u[14], u[15], u[16]<<8 | u[17]);
qlock(&cnlock);
if((p = cnfind(a)) == nil)
p = cnins(fd, a, u, &h, 0);
qunlock(&cnlock);
m.p = p;
if(n - Hdrsz < 0){ /* FIXME */
m.n = n;
memcpy(m.buf, udpbuf, m.n);
}else{
m.n = n - Hdrsz;
memcpy(m.buf, udpbuf+Hdrsz, m.n);
}
if(send(c, &m) < 0 || nbsend(fuckchan, nil) < 0){
fprint(2, "uproc: %r");
break;
}
}
}
qboolean
NET_GetPacket(netsrc_t src, netadr_t *from, sizebuf_t *d)
{
int n;
Conmsg m;
if(looprecv(src, from, d))
return true;
if(cfd == -1)
return false;
if((n = nbrecv(src == NS_SERVER ? udpchan : clchan, &m)) < 0)
sysfatal("NET_GetPacket:nbrecv: %r");
if(n == 0)
return false;
memcpy(from->ip, m.p->u+12, 4);
from->port = m.p->u[17] << 8 | m.p->u[16];
if(m.n == d->maxsize){
Com_Printf("Oversize packet from %s\n", NET_AdrToString(*from));
return false;
}
from->type = NA_IP;
d->cursize = m.n;
memcpy(d->data, m.buf, m.n);
return true;
}
void
NET_SendPacket(netsrc_t src, int length, void *data, netadr_t to)
{
int fd;
char *addr, *s, *lport;
uchar b[Bufsz+Hdrsz], u[IPaddrlen+2];
Conlist *p;
switch(to.type){
case NA_LOOPBACK:
loopsend(src, length, data, to);
break;
case NA_BROADCAST_IPX:
case NA_IPX:
break;
case NA_BROADCAST:
memset(to.ip, 0xff, 4);
addr = NET_AdrToString(to); /* port is PORT_SERVER */
s = strrchr(addr, ':');
*s++ = '\0';
if((fd = dial(netmkaddr(addr, "udp", s), clsrv, nil, nil)) < 0)
sysfatal("NET_SendPacket:dial bcast: %r");
if(write(fd, data, length) != length)
sysfatal("NET_SendPacket:write bcast: %r");
close(fd);
break;
case NA_IP:
if(cfd == -1)
break;
addr = NET_AdrToString(to);
qlock(&cnlock);
p = cnfind(addr);
qunlock(&cnlock);
if(p != nil){
fd = p->dfd;
if(fd == ufd || fd == cldfd){
memcpy(b, &p->h, Hdrsz);
memcpy(b+Hdrsz, data, length);
write(fd, b, length+Hdrsz);
break;
}
}else{
lport = strrchr(addr, ':');
*lport++ = '\0';
s = netmkaddr(addr, "udp", lport);
if((fd = dial(s, srv, nil, nil)) < 0)
sysfatal("NET_SendPacket:dial: %r");
memcpy(u, v4prefix, sizeof v4prefix);
memcpy(u+IPv4off, to.ip, IPv4addrlen);
u[16] = to.port;
u[17] = to.port >> 8;
*(lport-1) = ':';
qlock(&cnlock);
p = cnins(fd, addr, u, nil, src);
qunlock(&cnlock);
if(proccreate(dproc, p, 8192) < 0)
sysfatal("NET_SendPacket:proccreate: %r");
}
if(write(fd, data, length) != length)
sysfatal("NET_SendPacket:write: %r");
break;
default:
Com_Error(ERR_FATAL, "NET_SendPacket: bad address type");
}
}
void
NET_Sleep(int ms) /* sleep for ms, or wakeup for stdio or incoming packets */
{
if(cfd == -1 || dedicated != nil && !dedicated->value)
return; // we're not a server, just run full speed
if(send(tchan, &ms) < 0)
sysfatal("NET_Sleep:send: %r");
if(recv(fuckchan, nil) < 0)
sysfatal("NET_Sleep:recv: %r");
ms = -1;
if(nbsend(tchan, &ms) < 0) /* stop timer */
sysfatal("NET_Sleep:nbsend: %r");
}
static int
openname(char *port, int *dfd, Channel **c)
{
int fd;
char data[64], adir[40];
if((fd = announce(netmkaddr("*", "udp", port), adir)) < 0)
sysfatal("openname:announce udp!*!%s: %r", port);
if(fprint(fd, "headers") < 0)
sysfatal("openname: failed to set header mode: %r");
snprint(data, sizeof data, "%s/data", adir);
if((*dfd = open(data, ORDWR)) < 0)
sysfatal("openname:open %r");
if((*c = chancreate(sizeof(Conmsg), Nbuf)) == nil)
sysfatal("openname:chancreate: %r");
if(proccreate(uproc, *c, 8192) < 0)
sysfatal("openname:proccreate: %r");
return fd;
}
static void
openudp(void)
{
if(cfd != -1)
return;
/* svport value can be changed at any time */
if(svport->value == PORT_ANY || svport->value > 32767)
/* FIXME */
strncpy(srv, "*", sizeof(srv)-1);
else
strncpy(srv, svport->string, sizeof(srv)-1);
cfd = openname(srv, &ufd, &udpchan);
/* broadcast kluge */
if(clport->value == PORT_ANY || clport->value > 32767)
strncpy(clsrv, "*", sizeof(clsrv)-1);
else
strncpy(clsrv, clport->string, sizeof(clsrv)-1);
clfd = openname(clsrv, &cldfd, &clchan);
}
/* a single player game will only use the loopback code */
void
NET_Config(qboolean multiplayer)
{
if(!multiplayer){ /* shut down existing udp connections */
threadintgrp(THnet);
cnnuke();
if(udpchan != nil){
chanfree(udpchan);
udpchan = nil;
}
if(clchan != nil){
chanfree(clchan);
clchan = nil;
}
if(cfd != -1){
close(cfd);
cfd = -1;
}
if(clfd != -1){
close(clfd);
clfd = -1;
}
if(ufd != -1){
close(ufd);
ufd = -1;
}
if(cldfd != -1){
close(cldfd);
cldfd = -1;
}
}else{ /* announce open line and get cfd for it */
cninit();
openudp();
}
}
void
NET_Shutdown(void)
{
NET_Config(false);
}
void
NET_Init(void)
{
svport = Cvar_Get("port", va("%hu", PORT_SERVER), CVAR_NOSET);
clport = Cvar_Get("clport", va("%hu", CLPORT), CVAR_NOSET);
}