From 081d57ba339469767fe6cf0ddec7c75fc789cc1a Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Sat, 19 Apr 2003 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 2003-04-19

---
 ip/rudp.c | 63 ++++++++++++++++++++++++++++---------------------------
 1 file changed, 32 insertions(+), 31 deletions(-)

diff --git a/ip/rudp.c b/ip/rudp.c
index b72c01fc1659749b20159db95c5acc1ceeba2cb2..ce43133377923305005a69e8825f2154b7a903dc 100644
--- a/ip/rudp.c
+++ b/ip/rudp.c
@@ -30,6 +30,7 @@ enum
 	UDP_RHDRSIZE	= 36,	/* pseudo header + udp header + rudp header */
 	UDP_IPHDR	= 8,	/* ip header */
 	IP_UDPPROTO	= 254,
+	UDP_USEAD7	= 52,
 	UDP_USEAD6	= 36,
 	UDP_USEAD4	= 12,
 
@@ -357,9 +358,9 @@ rudpkick(void *x)
 
 	ucb = (Rudpcb*)c->ptcl;
 	switch(ucb->headers) {
-	case 6:
+	case 7:
 		/* get user specified addresses */
-		bp = pullupblock(bp, UDP_USEAD6);
+		bp = pullupblock(bp, UDP_USEAD7);
 		if(bp == nil)
 			return;
 		ipmove(raddr, bp->rp);
@@ -369,18 +370,20 @@ rudpkick(void *x)
 		/* pick interface closest to dest */
 		if(ipforme(f, laddr) != Runi)
 			findlocalip(f, laddr, raddr);
+		bp->rp += IPaddrlen;		/* Ignore ifc address */
 		rport = nhgets(bp->rp);
-
-		bp->rp += 4;			/* Igonore local port */
+		bp->rp += 2+2;			/* Ignore local port */
 		break;
-	case 4:
-		bp = pullupblock(bp, UDP_USEAD4);
+	case 6:
+		/* get user specified addresses */
+		bp = pullupblock(bp, UDP_USEAD6);
 		if(bp == nil)
 			return;
-		v4tov6(raddr, bp->rp);
-		bp->rp += IPv4addrlen;
-		v4tov6(laddr, bp->rp);
-		bp->rp += IPv4addrlen;
+		ipmove(raddr, bp->rp);
+		bp->rp += IPaddrlen;
+		ipmove(laddr, bp->rp);
+		bp->rp += IPaddrlen;
+		/* pick interface closest to dest */
 		if(ipforme(f, laddr) != Runi)
 			findlocalip(f, laddr, raddr);
 		rport = nhgets(bp->rp);
@@ -414,8 +417,8 @@ rudpkick(void *x)
 	uh->frag[1] = 0;
 	hnputs(uh->udpplen, ptcllen);
 	switch(ucb->headers){
-	case 4:
 	case 6:
+	case 7:
 		v6tov4(uh->udpdst, raddr);
 		hnputs(uh->udpdport, rport);
 		v6tov4(uh->udpsrc, laddr);
@@ -487,6 +490,7 @@ rudpiput(Proto *rudp, Ipifc *ifc, Block *bp)
 	ushort rport, lport;
 	Rudppriv *upriv;
 	Fs *f;
+	uchar *p;
 
 	upriv = rudp->priv;
 	f = rudp->f;
@@ -564,27 +568,24 @@ rudpiput(Proto *rudp, Ipifc *ifc, Block *bp)
 		raddr, rport, laddr, lport, len);
 
 	switch(ucb->headers){
-	case 6:
+	case 7:
 		/* pass the src address */
-		bp = padblock(bp, UDP_USEAD6);
-		ipmove(bp->rp, raddr);
-		if(ipforme(f, laddr) == Runi)
-			ipmove(bp->rp+IPaddrlen, laddr);
-		else
-			ipmove(bp->rp+IPaddrlen, ifc->lifc->local);
-		hnputs(bp->rp+2*IPaddrlen, rport);
-		hnputs(bp->rp+2*IPaddrlen+2, lport);
+		bp = padblock(bp, UDP_USEAD7);
+		p = bp->rp;
+		ipmove(p, raddr); p += IPaddrlen;
+		ipmove(p, laddr); p += IPaddrlen;
+		ipmove(p, ifc->lifc->local); p += IPaddrlen;
+		hnputs(p, rport); p += 2;
+		hnputs(p, lport);
 		break;
-	case 4:
+	case 6:
 		/* pass the src address */
-		bp = padblock(bp, UDP_USEAD4);
-		v6tov4(bp->rp, raddr);
-		if(ipforme(f, laddr) == Runi)
-			v6tov4(bp->rp+IPv4addrlen, laddr);
-		else
-			v6tov4(bp->rp+IPv4addrlen, ifc->lifc->local);
-		hnputs(bp->rp + 2*IPv4addrlen, rport);
-		hnputs(bp->rp + 2*IPv4addrlen + 2, lport);
+		bp = padblock(bp, UDP_USEAD6);
+		p = bp->rp;
+		ipmove(p, raddr); p += IPaddrlen;
+		ipmove(p, ipforme(f, laddr)==Runi ? laddr : ifc->lifc->local); p += IPaddrlen;
+		hnputs(p, rport); p += 2;
+		hnputs(p, lport);
 		break;
 	default:
 		/* connection oriented rudp */
@@ -628,8 +629,8 @@ rudpctl(Conv *c, char **f, int n)
 	if(n < 1)
 		return rudpunknown;
 
-	if(strcmp(f[0], "headers4") == 0){
-		ucb->headers = 4;
+	if(strcmp(f[0], "headers++4") == 0){
+		ucb->headers = 7;
 		return nil;
 	} else if(strcmp(f[0], "headers") == 0){
 		ucb->headers = 6;