Extend route command:

- add show as alias for get
	- add weights to allow mpath to do more than equal cost
	- add sticky / nostick to disable / re-enable per-connection load balancing

This adds a field to rt_metrics_lite so network bits of world will need to be re-built.

Reviewed by:	jeli & qingli

UPDATING

@@ -22,6 +22,13 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 8.x IS SLOW:
 	to maximize performance.  (To disable malloc debugging, run
 	ln -s aj /etc/malloc.conf.)
 
+20090414:
+	The size of rt_metrics_lite and by extension rtentry has changed.
+	Networking administration apps will need to be recompiled.
+	The route command now supports show as an alias for get, weighting 
+	of routes, sticky and nostick flags to alter the behavior of stateful
+	load balancing.
+	Bump __FreeBSD_version to 800078.
 20090408:
 	Do not use Giant for kbdmux(4) locking. This is wrong and
 	apparently causing more problems than it solves. This will

sbin/route/keywords

@@ -33,6 +33,7 @@ mtu
 net
 netmask
 nostatic
+nostick
 osi
 prefixlen
 proto1
@@ -44,8 +45,11 @@ rtt
 rttvar
 sa
 sendpipe
+show
 ssthresh
 static
+sticky
+weight
 x25
 xns
 xresolve

sbin/route/route.c

@@ -169,6 +169,7 @@ main(argc, argv)
 	if (*argv)
 		switch (keyword(*argv)) {
 		case K_GET:
+		case K_SHOW:
 			uid = 0;
 			/* FALLTHROUGH */
 
@@ -548,6 +549,7 @@ set_metric(value, key)
 	caseof(K_SSTHRESH, RTV_SSTHRESH, rmx_ssthresh);
 	caseof(K_RTT, RTV_RTT, rmx_rtt);
 	caseof(K_RTTVAR, RTV_RTTVAR, rmx_rttvar);
+	caseof(K_WEIGHT, RTV_WEIGHT, rmx_weight);
 	}
 	rtm_inits |= flag;
 	if (lockrest || locking)
@@ -571,8 +573,9 @@ newroute(argc, argv)
 		errx(EX_NOPERM, "must be root to alter routing table");
 	}
 	cmd = argv[0];
-	if (*cmd != 'g')
+	if (*cmd != 'g' && *cmd != 's')
 		shutdown(s, SHUT_RD); /* Don't want to read back our messages */
+
 	while (--argc > 0) {
 		if (**(++argv)== '-') {
 			switch (key = keyword(1 + *argv)) {
@@ -635,6 +638,12 @@ newroute(argc, argv)
 			case K_STATIC:
 				flags |= RTF_STATIC;
 				break;
+			case K_STICKY:
+				flags |= RTF_STICKY;
+				break;
+			case K_NOSTICK:
+				flags &= ~RTF_STICKY;
+				break;
 			case K_IFA:
 				if (!--argc)
 					usage((char *)NULL);
@@ -688,6 +697,7 @@ newroute(argc, argv)
 			case K_SSTHRESH:
 			case K_RTT:
 			case K_RTTVAR:
+			case K_WEIGHT:
 				if (!--argc)
 					usage((char *)NULL);
 				set_metric(*++argv, key);
@@ -741,7 +751,7 @@ newroute(argc, argv)
 		} else
 			break;
 	}
-	if (*cmd == 'g')
+	if (*cmd == 'g' || *cmd == 's')
 		exit(ret != 0);
 	if (!qflag) {
 		oerrno = errno;
@@ -1193,7 +1203,7 @@ rtmsg(cmd, flags)
 		cmd = RTM_ADD;
 	else if (cmd == 'c')
 		cmd = RTM_CHANGE;
-	else if (cmd == 'g') {
+	else if (cmd == 'g' || cmd == 's') {
 		cmd = RTM_GET;
 		if (so_ifp.sa.sa_family == 0) {
 			so_ifp.sa.sa_family = AF_LINK;
@@ -1297,13 +1307,13 @@ char *msgtypes[] = {
 };
 
 char metricnames[] =
-"\011pksent\010rttvar\7rtt\6ssthresh\5sendpipe\4recvpipe\3expire\2hopcount"
+"\011weight\010rttvar\7rtt\6ssthresh\5sendpipe\4recvpipe\3expire"
 "\1mtu";
 char routeflags[] =
-"\1UP\2GATEWAY\3HOST\4REJECT\5DYNAMIC\6MODIFIED\7DONE\010MASK_PRESENT"
+"\1UP\2GATEWAY\3HOST\4REJECT\5DYNAMIC\6MODIFIED\7DONE"
-"\011CLONING\012XRESOLVE\013LLINFO\014STATIC\015BLACKHOLE\016b016"
+"\012XRESOLVE\013LLINFO\014STATIC\015BLACKHOLE"
-"\017PROTO2\020PROTO1\021PRCLONING\022WASCLONED\023PROTO3\024CHAINDELETE"
+"\017PROTO2\020PROTO1\021PRCLONING\022WASCLONED\023PROTO3"
-"\025PINNED\026LOCAL\027BROADCAST\030MULTICAST";
+"\025PINNED\026LOCAL\027BROADCAST\030MULTICAST\035STICKY";
 char ifnetflags[] =
 "\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5PTP\6b6\7RUNNING\010NOARP"
 "\011PPROMISC\012ALLMULTI\013OACTIVE\014SIMPLEX\015LINK0\016LINK1"
@@ -1466,14 +1476,13 @@ print_getmsg(rtm, msglen)
 #define msec(u)	(((u) + 500) / 1000)		/* usec to msec */
 
 	(void) printf("\n%s\n", "\
- recvpipe  sendpipe  ssthresh  rtt,msec    rttvar  hopcount      mtu     expire");
+ recvpipe  sendpipe  ssthresh  rtt,msec    mtu        weight    expire");
 	printf("%8ld%c ", rtm->rtm_rmx.rmx_recvpipe, lock(RPIPE));
 	printf("%8ld%c ", rtm->rtm_rmx.rmx_sendpipe, lock(SPIPE));
 	printf("%8ld%c ", rtm->rtm_rmx.rmx_ssthresh, lock(SSTHRESH));
 	printf("%8ld%c ", msec(rtm->rtm_rmx.rmx_rtt), lock(RTT));
-	printf("%8ld%c ", msec(rtm->rtm_rmx.rmx_rttvar), lock(RTTVAR));
-	printf("%8ld%c ", rtm->rtm_rmx.rmx_hopcount, lock(HOPCOUNT));
 	printf("%8ld%c ", rtm->rtm_rmx.rmx_mtu, lock(MTU));
+	printf("%8ld%c ", rtm->rtm_rmx.rmx_weight, lock(WEIGHT));
 	if (rtm->rtm_rmx.rmx_expire)
 		rtm->rtm_rmx.rmx_expire -= time(0);
 	printf("%8ld%c\n", rtm->rtm_rmx.rmx_expire, lock(EXPIRE));

sys/net/radix_mpath.c

@@ -77,15 +77,18 @@ rn_mpath_next(struct radix_node *rn)
 		return NULL;
 }
 
-u_int32_t
+uint32_t
 rn_mpath_count(struct radix_node *rn)
 {
-	u_int32_t i;
+	uint32_t i = 0;
-
+	struct rtentry *rt;
-	i = 1;
+	
-	while ((rn = rn_mpath_next(rn)) != NULL)
+	while (rn != NULL) {
-		i++;
+		rt = (struct rtentry *)rn;
-	return i;
+		i += rt->rt_rmx.rmx_weight;
+		rn = rn_mpath_next(rn);
+	}
+	return (i);
 }
 
 struct rtentry *
@@ -256,10 +259,12 @@ different:
 }
 
 void
-rtalloc_mpath_fib(struct route *ro, u_int32_t hash, u_int fibnum)
+rtalloc_mpath_fib(struct route *ro, uint32_t hash, u_int fibnum)
 {
 	struct radix_node *rn0, *rn;
 	u_int32_t n;
+	struct rtentry *rt;
+	int64_t weight;
 
 	/*
 	 * XXX we don't attempt to lookup cached route again; what should
@@ -284,25 +289,31 @@ rtalloc_mpath_fib(struct route *ro, u_int32_t hash, u_int fibnum)
 	/* gw selection by Modulo-N Hash (RFC2991) XXX need improvement? */
 	hash += hashjitter;
 	hash %= n;
-	while (hash-- > 0 && rn) {
+	for (weight = abs((int32_t)hash), rt = ro->ro_rt;
+	     weight >= rt->rt_rmx.rmx_weight && rn; 
+	     weight -= rt->rt_rmx.rmx_weight) {
+		
 		/* stay within the multipath routes */
 		if (rn->rn_dupedkey && rn->rn_mask != rn->rn_dupedkey->rn_mask)
 			break;
 		rn = rn->rn_dupedkey;
+		rt = (struct rtentry *)rn;
 	}
-
 	/* XXX try filling rt_gwroute and avoid unreachable gw  */
 
-	/* if gw selection fails, use the first match (default) */
+	/* gw selection has failed - there must be only zero weight routes */
 	if (!rn) {
 		RT_UNLOCK(ro->ro_rt);
+		ro->ro_rt = NULL;
 		return;
 	}
-	
+	if (ro->ro_rt != rt) {
-	RTFREE_LOCKED(ro->ro_rt);
+		RTFREE_LOCKED(ro->ro_rt);
-	ro->ro_rt = (struct rtentry *)rn;
+		ro->ro_rt = (struct rtentry *)rn;
-	RT_LOCK(ro->ro_rt);
+		RT_LOCK(ro->ro_rt);
-	RT_ADDREF(ro->ro_rt);
+		RT_ADDREF(ro->ro_rt);
+
+	} 
 	RT_UNLOCK(ro->ro_rt);
 }
 

sys/net/route.c

@@ -826,6 +826,103 @@ bad:
 	return (error);
 }
 
+#ifdef RADIX_MPATH
+static int
+rn_mpath_update(int req, struct rt_addrinfo *info,
+    struct radix_node_head *rnh, struct rtentry **ret_nrt)
+{
+	/*
+	 * if we got multipath routes, we require users to specify
+	 * a matching RTAX_GATEWAY.
+	 */
+	struct rtentry *rt, *rto = NULL;
+	register struct radix_node *rn;
+	int error = 0;
+
+	rn = rnh->rnh_matchaddr(dst, rnh);
+	if (rn == NULL)
+		return (ESRCH);
+	rto = rt = RNTORT(rn);
+	rt = rt_mpath_matchgate(rt, gateway);
+	if (rt == NULL)
+		return (ESRCH);
+	/*
+	 * this is the first entry in the chain
+	 */
+	if (rto == rt) {
+		rn = rn_mpath_next((struct radix_node *)rt);
+		/*
+		 * there is another entry, now it's active
+		 */
+		if (rn) {
+			rto = RNTORT(rn);
+			RT_LOCK(rto);
+			rto->rt_flags |= RTF_UP;
+			RT_UNLOCK(rto);
+		} else if (rt->rt_flags & RTF_GATEWAY) {
+			/*
+			 * For gateway routes, we need to 
+			 * make sure that we we are deleting
+			 * the correct gateway. 
+			 * rt_mpath_matchgate() does not 
+			 * check the case when there is only
+			 * one route in the chain.  
+			 */
+			if (gateway &&
+			    (rt->rt_gateway->sa_len != gateway->sa_len ||
+				memcmp(rt->rt_gateway, gateway, gateway->sa_len)))
+				error = ESRCH;
+			goto done;
+		}
+		/*
+		 * use the normal delete code to remove
+		 * the first entry
+		 */
+		if (req != RTM_DELETE) 
+			goto nondelete;
+
+		error = ENOENT;
+		goto done;
+	}
+		
+	/*
+	 * if the entry is 2nd and on up
+	 */
+	if ((req == RTM_DELETE) && !rt_mpath_deldup(rto, rt))
+		panic ("rtrequest1: rt_mpath_deldup");
+	RT_LOCK(rt);
+	RT_ADDREF(rt);
+	if (req == RTM_DELETE) {
+		rt->rt_flags &= ~RTF_UP;
+		/*
+		 * One more rtentry floating around that is not
+		 * linked to the routing table. rttrash will be decremented
+		 * when RTFREE(rt) is eventually called.
+		 */
+		V_rttrash++;
+		
+	}
+	
+nondelete:
+	if (req != RTM_DELETE)
+		panic("unrecognized request %d", req);
+	
+
+	/*
+	 * If the caller wants it, then it can have it,
+	 * but it's up to it to free the rtentry as we won't be
+	 * doing it.
+	 */
+	if (ret_nrt) {
+		*ret_nrt = rt;
+		RT_UNLOCK(rt);
+	} else
+		RTFREE_LOCKED(rt);
+done:
+	return (error);
+}
+#endif
+
 int
 rtrequest1_fib(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt,
 				u_int fibnum)
@@ -864,65 +961,15 @@ rtrequest1_fib(int req, struct rt_addrinfo *info, struct rtentry **ret_nrt,
 	switch (req) {
 	case RTM_DELETE:
 #ifdef RADIX_MPATH
-		/*
-		 * if we got multipath routes, we require users to specify
-		 * a matching RTAX_GATEWAY.
-		 */
 		if (rn_mpath_capable(rnh)) {
-			struct rtentry *rto = NULL;
+			error = rn_mpath_update(req, info, rnh, ret_nrt);
-
-			rn = rnh->rnh_matchaddr(dst, rnh);
-			if (rn == NULL)
-				senderr(ESRCH);
- 			rto = rt = RNTORT(rn);
-			rt = rt_mpath_matchgate(rt, gateway);
-			if (!rt)
-				senderr(ESRCH);
 			/*
-			 * this is the first entry in the chain
+			 * "bad" holds true for the success case
+			 * as well
 			 */
-			if (rto == rt) {
+			if (error != ENOENT)
-				rn = rn_mpath_next((struct radix_node *)rt);
+				goto bad;
-				/*
-				 * there is another entry, now it's active
-				 */
-				if (rn) {
-					rto = RNTORT(rn);
-					RT_LOCK(rto);
-					rto->rt_flags |= RTF_UP;
-					RT_UNLOCK(rto);
-				} else if (rt->rt_flags & RTF_GATEWAY) {
-					/*
-					 * For gateway routes, we need to 
-					 * make sure that we we are deleting
-					 * the correct gateway. 
-					 * rt_mpath_matchgate() does not 
-					 * check the case when there is only
-					 * one route in the chain.  
-					 */
-					if (gateway &&
-					    (rt->rt_gateway->sa_len != gateway->sa_len ||
-					    memcmp(rt->rt_gateway, gateway, gateway->sa_len)))
-						senderr(ESRCH);
-				}
-				/*
-				 * use the normal delete code to remove
-				 * the first entry
-				 */
-				goto normal_rtdel;
-			}
-			/*
-			 * if the entry is 2nd and on up
-			 */
-			if (!rt_mpath_deldup(rto, rt))
-				panic ("rtrequest1: rt_mpath_deldup");
-			RT_LOCK(rt);
-			RT_ADDREF(rt);
-			rt->rt_flags &= ~RTF_UP;
-			goto deldone;  /* done with the RTM_DELETE command */
 		}
-
-normal_rtdel:
 #endif
 		/*
 		 * Remove the item from the tree and return it.
@@ -944,9 +991,6 @@ normal_rtdel:
 		if ((ifa = rt->rt_ifa) && ifa->ifa_rtrequest)
 			ifa->ifa_rtrequest(RTM_DELETE, rt, info);
 
-#ifdef RADIX_MPATH
-deldone:
-#endif
 		/*
 		 * One more rtentry floating around that is not
 		 * linked to the routing table. rttrash will be decremented
@@ -1019,6 +1063,7 @@ deldone:
 		IFAREF(ifa);
 		rt->rt_ifa = ifa;
 		rt->rt_ifp = ifa->ifa_ifp;
+		rt->rt_rmx.rmx_weight = 1;
 
 #ifdef RADIX_MPATH
 		/* do not permit exactly the same dst/mask/gw pair */

sys/net/route.h

@@ -58,6 +58,7 @@ struct rt_metrics_lite {
 	u_long	rmx_mtu;	/* MTU for this path */
 	u_long	rmx_expire;	/* lifetime for route, e.g. redirect */
 	u_long	rmx_pksent;	/* packets sent using this route */
+	u_long	rmx_weight;	/* absolute weight */ 
 };
 
 struct rt_metrics {
@@ -71,7 +72,8 @@ struct rt_metrics {
 	u_long	rmx_rtt;	/* estimated round trip time */
 	u_long	rmx_rttvar;	/* estimated rtt variance */
 	u_long	rmx_pksent;	/* packets sent using this route */
-	u_long	rmx_filler[4];	/* will be used for T/TCP later */
+	u_long	rmx_weight;	/* route weight */
+	u_long	rmx_filler[3];	/* will be used for T/TCP later */
 };
 
 /*
@@ -193,13 +195,15 @@ struct ortentry {
 #define	RTF_LOCAL	0x200000 	/* route represents a local address */
 #define	RTF_BROADCAST	0x400000	/* route represents a bcast address */
 #define	RTF_MULTICAST	0x800000	/* route represents a mcast address */
-					/* 0x1000000 and up unassigned */
+					/* 0x8000000 and up unassigned */
-#define	RTF_RNH_LOCKED	 0x40000000	/* radix node head locked by caller */
+#define	RTF_STICKY	 0x10000000	/* always route dst->src */
+
+#define	RTF_RNH_LOCKED	 0x40000000	/* radix node head is locked */
 
 /* Mask of RTF flags that are allowed to be modified by RTM_CHANGE. */
 #define RTF_FMASK	\
 	(RTF_PROTO1 | RTF_PROTO2 | RTF_PROTO3 | RTF_BLACKHOLE | \
-	 RTF_REJECT | RTF_STATIC)
+	 RTF_REJECT | RTF_STATIC | RTF_STICKY)
 
 /*
  * Routing statistics.
@@ -225,12 +229,11 @@ struct rt_msghdr {
 	int	rtm_seq;	/* for sender to identify action */
 	int	rtm_errno;	/* why failed */
 	int	rtm_fmask;	/* bitmask used in RTM_CHANGE message */
-#define	rtm_use	rtm_fmask	/* deprecated, use rtm_rmx->rmx_pksent */
 	u_long	rtm_inits;	/* which metrics we are initializing */
 	struct	rt_metrics rtm_rmx; /* metrics themselves */
 };
 
-#define RTM_VERSION	5	/* Up the ante and ignore older versions */
+#define RTM_VERSION	6	/* Up the ante and ignore older versions */
 
 /*
  * Message types.
@@ -265,6 +268,7 @@ struct rt_msghdr {
 #define RTV_SSTHRESH	0x20	/* init or lock _ssthresh */
 #define RTV_RTT		0x40	/* init or lock _rtt */
 #define RTV_RTTVAR	0x80	/* init or lock _rttvar */
+#define RTV_WEIGHT	0x100	/* init or lock _weight */
 
 /*
  * Bitmask values for rtm_addrs.

sys/net/rtsock.c

@@ -637,7 +637,6 @@ route_output(struct mbuf *m, struct socket *so)
 			}
 			(void)rt_msg2(rtm->rtm_type, &info, (caddr_t)rtm, NULL);
 			rtm->rtm_flags = rt->rt_flags;
-			rtm->rtm_use = 0;
 			rt_getmetrics(&rt->rt_rmx, &rtm->rtm_rmx);
 			rtm->rtm_addrs = info.rti_addrs;
 			break;
@@ -691,10 +690,8 @@ route_output(struct mbuf *m, struct socket *so)
 				rt->rt_ifp = info.rti_ifp;
 			}
 			/* Allow some flags to be toggled on change. */
-			if (rtm->rtm_fmask & RTF_FMASK)
+			rt->rt_flags = (rt->rt_flags & ~RTF_FMASK) |
-				rt->rt_flags = (rt->rt_flags &
+				    (rtm->rtm_flags & RTF_FMASK);
-				    ~rtm->rtm_fmask) |
-				    (rtm->rtm_flags & rtm->rtm_fmask);
 			rt_setmetrics(rtm->rtm_inits, &rtm->rtm_rmx,
 					&rt->rt_rmx);
 			rtm->rtm_index = rt->rt_ifp->if_index;
@@ -773,6 +770,7 @@ rt_setmetrics(u_long which, const struct rt_metrics *in,
 	 * of tcp hostcache. The rest is ignored.
 	 */
 	metric(RTV_MTU, rmx_mtu);
+	metric(RTV_WEIGHT, rmx_weight);
 	/* Userland -> kernel timebase conversion. */
 	if (which & RTV_EXPIRE)
 		out->rmx_expire = in->rmx_expire ?
@@ -786,6 +784,7 @@ rt_getmetrics(const struct rt_metrics_lite *in, struct rt_metrics *out)
 #define metric(e) out->e = in->e;
 	bzero(out, sizeof(*out));
 	metric(rmx_mtu);
+	metric(rmx_weight);
 	/* Kernel -> userland timebase conversion. */
 	out->rmx_expire = in->rmx_expire ?
 	    in->rmx_expire - time_uptime + time_second : 0;
@@ -1257,7 +1256,10 @@ sysctl_dumpentry(struct radix_node *rn, void *vw)
 		struct rt_msghdr *rtm = (struct rt_msghdr *)w->w_tmem;
 
 		rtm->rtm_flags = rt->rt_flags;
-		rtm->rtm_use = rt->rt_rmx.rmx_pksent;
+		/*
+		 * let's be honest about this being a retarded hack
+		 */
+		rtm->rtm_fmask = rt->rt_rmx.rmx_pksent;
 		rt_getmetrics(&rt->rt_rmx, &rtm->rtm_rmx);
 		rtm->rtm_index = rt->rt_ifp->if_index;
 		rtm->rtm_errno = rtm->rtm_pid = rtm->rtm_seq = 0;

sys/sys/param.h

@@ -57,7 +57,7 @@
  *		is created, otherwise 1.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 800077	/* Master, propagated to newvers */
+#define __FreeBSD_version 800078	/* Master, propagated to newvers */
 
 #ifndef LOCORE
 #include <sys/types.h>