1998/0306/ip/udp.c (diff list | history)

ip/udp.c on 1997/0327
1997/0327		#include "u.h" #include "../port/lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" #include "ip.h" #define DPRINT if(0)print enum { UDP_PHDRSIZE = 12, UDP_HDRSIZE = 20, UDP_IPHDR = 8, IP_UDPPROTO = 17,
1998/0306		UDP_USEAD = 36,
1997/0327		Udprxms = 200, Udptickms = 100, Udpmaxxmit = 10, }; typedef struct Udphdr Udphdr; struct Udphdr { /* ip header */
1998/0306		uchar vihl; /* Version and header length */ uchar tos; /* Type of service */ uchar length[2]; /* packet length */ uchar id[2]; /* Identification */ uchar frag[2]; /* Fragment information */ uchar Unused; uchar udpproto; /* Protocol */ uchar udpplen[2]; /* Header plus data length */ uchar udpsrc[4]; /* Ip source */ uchar udpdst[4]; /* Ip destination */
1997/0327		/* udp header */
1998/0306		uchar udpsport[2]; /* Source port */ uchar udpdport[2]; /* Destination port */ uchar udplen[2]; /* data length */ uchar udpcksum[2]; /* Checksum */
1997/0327		}; /* * protocol specific part of Conv */ typedef struct Udpcb Udpcb; struct Udpcb { QLock;
1998/0306		uchar headers;
1997/0327		}; Proto udp; int udpsum; uint generation; extern Fs fs; int udpdebug; static char* udpconnect(Conv *c, char **argv, int argc) { char *e; e = Fsstdconnect(c, argv, argc); Fsconnected(&fs, c, e); return e; }
1998/0306		static int udpstate(Conv *c, char *state, int n)
1997/0327		{ USED(c);
1998/0306		return snprint(state, n, "%s", "Datagram");
1997/0327		}
1997/0403		static char*
1997/0411		udpannounce(Conv *c, char** argv, int argc)
1997/0327		{
1997/0411		char *e; e = Fsstdannounce(c, argv, argc); if(e != nil) return e;
1997/0327		Fsconnected(&fs, c, nil);
1997/0403		return nil;
1997/0327		} static void udpcreate(Conv *c) {
1997/0806		c->rq = qopen(64*1024, 1, 0, 0); c->wq = qopen(64*1024, 0, 0, 0);
1997/0327		} static void udpclose(Conv *c) { Udpcb *ucb; qclose(c->rq); qclose(c->wq); qclose(c->eq);
1998/0306		ipmove(c->laddr, IPnoaddr); ipmove(c->raddr, IPnoaddr);
1997/0327		c->lport = 0; c->rport = 0; ucb = (Udpcb*)c->ptcl; ucb->headers = 0; unlock(c); } void
1998/0306		udpkick(Conv *c, int)
1997/0327		{ Udphdr *uh;
1997/0530		ushort rport;
1998/0306		uchar laddr[IPaddrlen], raddr[IPaddrlen];
1997/0806		Block *bp;
1997/0327		Udpcb *ucb; int dlen, ptcllen;
1998/0306		netlog(Logudp, "udp: kick\n");
1997/0327		bp = qget(c->wq); if(bp == nil) return; ucb = (Udpcb*)c->ptcl; if(ucb->headers) { /* get user specified addresses */ bp = pullupblock(bp, UDP_USEAD);
1998/0306		if(bp == nil)
1997/0327		return;
1998/0306		ipmove(raddr, bp->rp); bp->rp += IPaddrlen; ipmove(laddr, bp->rp); bp->rp += IPaddrlen; if(ipforme(laddr) != Runi) findlocalip(laddr, raddr); /* pick interface closest to dest */
1997/0530		rport = nhgets(bp->rp);
1997/0327		bp->rp += 2;
1997/0530		/* ignore local port number */ bp->rp += 2;
1997/0327		} else {
1997/0530		rport = 0;
1997/0327		} dlen = blocklen(bp); /* Make space to fit udp & ip header */ bp = padblock(bp, UDP_IPHDR+UDP_HDRSIZE); if(bp == nil) return; uh = (Udphdr *)(bp->rp); ptcllen = dlen + (UDP_HDRSIZE-UDP_PHDRSIZE); uh->Unused = 0; uh->udpproto = IP_UDPPROTO; uh->frag[0] = 0; uh->frag[1] = 0; hnputs(uh->udpplen, ptcllen); if(ucb->headers) {
1998/0306		v6tov4(uh->udpdst, raddr);
1997/0530		hnputs(uh->udpdport, rport);
1998/0306		v6tov4(uh->udpsrc, laddr);
1997/0327		} else {
1998/0306		v6tov4(uh->udpdst, c->raddr);
1997/0327		hnputs(uh->udpdport, c->rport);
1998/0306		if(ipcmp(c->laddr, IPnoaddr) == 0) findlocalip(c->laddr, c->raddr); /* pick interface closest to dest */ v6tov4(uh->udpsrc, c->laddr);
1997/0327		} hnputs(uh->udpsport, c->lport); hnputs(uh->udplen, ptcllen); uh->udpcksum[0] = 0; uh->udpcksum[1] = 0; hnputs(uh->udpcksum, ptclcsum(bp, UDP_IPHDR, dlen+UDP_HDRSIZE)); ipoput(bp, 0, c->ttl); } void
1998/0306		udpiput(uchar *ia, Block *bp)
1997/0327		{
1997/0904		int len, olen, ottl;
1997/0327		Udphdr *uh; Conv *c, **p; Udpcb *ucb;
1998/0306		uchar raddr[IPaddrlen], laddr[IPaddrlen];
1997/0530		ushort rport, lport;
1997/0327		uh = (Udphdr*)(bp->rp);
1997/0904		/* Put back pseudo header for checksum (remember old values for icmpnoconv()) */ ottl = uh->Unused;
1997/0327		uh->Unused = 0; len = nhgets(uh->udplen);
1997/0904		olen = nhgets(uh->udpplen);
1997/0327		hnputs(uh->udpplen, len);
1998/0306		v4tov6(raddr, uh->udpsrc); v4tov6(laddr, uh->udpdst);
1997/0725		lport = nhgets(uh->udpdport); rport = nhgets(uh->udpsport);
1997/0327		if(udpsum && nhgets(uh->udpcksum)) { if(ptclcsum(bp, UDP_IPHDR, len+UDP_PHDRSIZE)) { udp.csumerr++;
1998/0306		netlog(Logudp, "udp: checksum error %I\n", raddr);
1997/0327		freeblist(bp); return; } } /* Look for a conversation structure for this port */ c = nil; for(p = udp.conv; *p; p++) { c = *p; if(c->inuse == 0) continue;
1997/0530		if(c->lport == lport && (c->rport == 0 || c->rport == rport))
1997/0327		break; } if(*p == nil) {
1998/0306		netlog(Logudp, "udp: no conv %I.%d -> %I.%d\n", raddr, rport, laddr, lport);
1997/0904		/* don't complain about broadcasts... */
1998/0306		if(ipforme(raddr) == 0){
1997/0904		uh->Unused = ottl; hnputs(uh->udpplen, olen); icmpnoconv(bp); }
1997/0327		freeblist(bp); return; } /* * Trim the packet down to data size */ len -= (UDP_HDRSIZE-UDP_PHDRSIZE); bp = trimblock(bp, UDP_IPHDR+UDP_HDRSIZE, len); if(bp == nil){
1998/0306		netlog(Logudp, "udp: len err %I.%d -> %I.%d\n", raddr, rport, laddr, lport);
1997/0327		udp.lenerr++; return; }
1997/0806
1998/0306		netlog(Logudpmsg, "udp: %I.%d -> %I.%d l %d\n", raddr, rport, laddr, lport, len);
1997/0327		ucb = (Udpcb*)c->ptcl; if(ucb->headers) { /* pass the src address */ bp = padblock(bp, UDP_USEAD);
1998/0306		ipmove(bp->rp, raddr); if(ipforme(laddr) == Runi) ipmove(bp->rp+IPaddrlen, laddr);
1997/0901		else
1998/0306		ipmove(bp->rp+IPaddrlen, ia); hnputs(bp->rp+2*IPaddrlen, rport); hnputs(bp->rp+2*IPaddrlen+2, lport);
1997/0327		} else { /* connection oriented udp */ if(c->raddr == 0){ /* save the src address in the conversation */
1998/0306		ipmove(c->raddr, raddr);
1997/0530		c->rport = rport;
1997/0327		/* reply with the same ip address (if not broadcast) */
1998/0306		if(ipforme(laddr) == Runi) ipmove(c->laddr, laddr);
1997/0708		else
1998/0306		ipmove(c->laddr, ia);
1997/0327		} } if(bp->next) bp = concatblock(bp);
1997/0725		if(qfull(c->rq)){
1998/0306		netlog(Logudp, "udp: qfull %I.%d -> %I.%d\n", raddr, rport, laddr, lport);
1997/0327		freeblist(bp);
1997/0725		}else
1997/0327		qpass(c->rq, bp); } char* udpctl(Conv *c, char **f, int n) { Udpcb *ucb; ucb = (Udpcb*)c->ptcl; if(n == 1 && strcmp(f[0], "headers") == 0){ ucb->headers = 1; return nil; } if(n == 1 && strcmp(f[0], "debug") == 0){ udpdebug = 1; return nil; } return "unknown control request"; } void
1997/0829		udpadvise(Block *bp, char *msg) { Udphdr *h;
1998/0306		uchar source[IPaddrlen], dest[IPaddrlen];
1997/0829		ushort psource, pdest; Conv *s, **p; h = (Udphdr*)(bp->rp);
1998/0306		v4tov6(dest, h->udpdst); v4tov6(source, h->udpsrc);
1997/0829		psource = nhgets(h->udpsport); pdest = nhgets(h->udpdport); /* Look for a connection */ for(p = udp.conv; *p; p++) { s = *p;
1998/0306		if(s->rport == pdest) if(s->lport == psource) if(ipcmp(s->raddr, dest) == 0) if(ipcmp(s->laddr, source) == 0){
1997/0829		qhangup(s->rq, msg); qhangup(s->wq, msg); break; } } freeblist(bp); }
1998/0306		int udpstats(char *buf, int len) { return snprint(buf, len, "udp: csum %d hlen %d len %d order %d rexmit %d\n", udp.csumerr, udp.hlenerr, udp.lenerr, udp.order, udp.rexmit); }
1997/0829		void
1997/0327		udpinit(Fs *fs) { udp.name = "udp"; udp.kick = udpkick; udp.connect = udpconnect; udp.announce = udpannounce; udp.ctl = udpctl; udp.state = udpstate; udp.create = udpcreate; udp.close = udpclose; udp.rcv = udpiput;
1997/0829		udp.advise = udpadvise;
1998/0306		udp.stats = udpstats;
1997/0327		udp.ipproto = IP_UDPPROTO; udp.nc = 16; udp.ptclsize = sizeof(Udpcb); Fsproto(fs, &udp); }