ref: 057aa6afc8274d0907981153155f41551bb73cde
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); }