This main goals of this project are:

1. separating L2 tables (ARP, NDP) from the L3 routing tables
2. removing as much locking dependencies among these layers as
   possible to allow for some parallelism in the search operations
3. simplify the logic in the routing code,

The most notable end result is the obsolescent of the route
cloning (RTF_CLONING) concept, which translated into code reduction
in both IPv4 ARP and IPv6 NDP related modules, and size reduction in
struct rtentry{}. The change in design obsoletes the semantics of
RTF_CLONING, RTF_WASCLONE and RTF_LLINFO routing flags. The userland
applications such as "arp" and "ndp" have been modified to reflect
those changes. The output from "netstat -r" shows only the routing
entries.

Quite a few developers have contributed to this project in the
past: Glebius Smirnoff, Luigi Rizzo, Alessandro Cerri, and
Andre Oppermann. And most recently:

- Kip Macy revised the locking code completely, thus completing
  the last piece of the puzzle, Kip has also been conducting
  active functional testing
- Sam Leffler has helped me improving/refactoring the code, and
  provided valuable reviews
- Julian Elischer setup the perforce tree for me and has helped
  me maintaining that branch before the svn conversion

UPDATING

@@ -22,6 +22,15 @@ 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.)
 
+20081214:
+	__FreeBSD_version 800059 incorporates the new arp-v2 rewrite.
+	RTF_CLONING, RTF_LLINFO and RTF_WASCLONED flags are eliminated.
+	The new code reduced struct rtentry{} by 16 bytes on 32-bit 
+	architecture and 40 bytes on 64-bit architecture. The userland
+	applications "arp" and "ndp" have been updated accordingly.
+	The output from "netstat -r" shows only routing entries and
+	none of the L2 information.
+
 20081130:
 	__FreeBSD_version 800057 marks the switchover from the
 	binary ath hal to source code. Users must add the line:

contrib/bsnmp/snmp_mibII/mibII.c

@@ -48,8 +48,7 @@ static void *route_fd;
 /* if-index allocator */
 static uint32_t next_if_index = 1;
 
-/* re-fetch arp table */
-static int update_arp;
+/* currently fetching the arp table */
 static int in_update_arp;
 
 /* OR registrations */
@@ -910,36 +909,6 @@ mib_find_ifa(struct in_addr addr)
 	return (NULL);
 }
 
-/*
- * Process a new ARP entry
- */
-static void
-process_arp(const struct rt_msghdr *rtm, const struct sockaddr_dl *sdl,
-    const struct sockaddr_in *sa)
-{
-	struct mibif *ifp;
-	struct mibarp *at;
-
-	/* IP arp table entry */
-	if (sdl->sdl_alen == 0) {
-		update_arp = 1;
-		return;
-	}
-	if ((ifp = mib_find_if_sys(sdl->sdl_index)) == NULL)
-		return;
-	/* have a valid entry */
-	if ((at = mib_find_arp(ifp, sa->sin_addr)) == NULL &&
-	    (at = mib_arp_create(ifp, sa->sin_addr,
-	    sdl->sdl_data + sdl->sdl_nlen, sdl->sdl_alen)) == NULL)
-		return;
-
-	if (rtm->rtm_rmx.rmx_expire == 0)
-		at->flags |= MIBARP_PERM;
-	else
-		at->flags &= ~MIBARP_PERM;
-	at->flags |= MIBARP_FOUND;
-}
-
 /*
  * Handle a routing socket message.
  */
@@ -1080,46 +1049,12 @@ handle_rtmsg(struct rt_msghdr *rtm)
 		}
 		break;
 #endif
-
 	  case RTM_GET:
-		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
-		if (rtm->rtm_flags & RTF_LLINFO) {
-			if (addrs[RTAX_DST] == NULL ||
-			    addrs[RTAX_GATEWAY] == NULL ||
-			    addrs[RTAX_DST]->sa_family != AF_INET ||
-			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
-				break;
-			process_arp(rtm,
-			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
-			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
-		} else {
-			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
-				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
-				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
-		}
-		break;
-
 	  case RTM_ADD:
-		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
-		if (rtm->rtm_flags & RTF_LLINFO) {
-			if (addrs[RTAX_DST] == NULL ||
-			    addrs[RTAX_GATEWAY] == NULL ||
-			    addrs[RTAX_DST]->sa_family != AF_INET ||
-			    addrs[RTAX_GATEWAY]->sa_family != AF_LINK)
-				break;
-			process_arp(rtm,
-			    (struct sockaddr_dl *)(void *)addrs[RTAX_GATEWAY],
-			    (struct sockaddr_in *)(void *)addrs[RTAX_DST]);
-		} else {
-			if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
-				mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
-				    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
-		}
-		break;
-
 	  case RTM_DELETE:
 		mib_extract_addrs(rtm->rtm_addrs, (u_char *)(rtm + 1), addrs);
-		if (rtm->rtm_errno == 0 && !(rtm->rtm_flags & RTF_LLINFO))
+
+		if (rtm->rtm_errno == 0 && (rtm->rtm_flags & RTF_UP))
 			mib_sroute_process(rtm, addrs[RTAX_GATEWAY],
 			    addrs[RTAX_DST], addrs[RTAX_NETMASK]);
 		break;
@@ -1289,7 +1224,8 @@ update_ifa_info(void)
 
 /*
  * Update arp table
- */
+ *
+*/
 void
 mib_arp_update(void)
 {
@@ -1305,11 +1241,11 @@ mib_arp_update(void)
 	TAILQ_FOREACH(at, &mibarp_list, link)
 		at->flags &= ~MIBARP_FOUND;
 
-	if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, RTF_LLINFO, &needed)) == NULL) {
+	if ((buf = mib_fetch_rtab(AF_INET, NET_RT_FLAGS, 0, &needed)) == NULL) {
 		in_update_arp = 0;
 		return;
 	}
-
+	
 	next = buf;
 	while (next < buf + needed) {
 		rtm = (struct rt_msghdr *)(void *)next;
@@ -1326,7 +1262,6 @@ mib_arp_update(void)
 		at = at1;
 	}
 	mibarpticks = get_ticks();
-	update_arp = 0;
 	in_update_arp = 0;
 }
 
@@ -1634,8 +1569,8 @@ mibII_idle(void)
 		mib_arp_update();
 		mib_iflist_bad = 0;
 	}
-	if (update_arp)
-		mib_arp_update();
+
+	mib_arp_update();
 }
 
 

contrib/bsnmp/snmp_mibII/mibII_route.c

@@ -186,8 +186,7 @@ mib_sroute_process(struct rt_msghdr *rtm, struct sockaddr *gw,
 	memcpy(r->index, key.index, sizeof(r->index));
 	r->ifindex = (ifp == NULL) ? 0 : ifp->index;
 
-	r->type = (rtm->rtm_flags & RTF_LLINFO) ? 3 :
-	    (rtm->rtm_flags & RTF_REJECT) ? 2 : 4;
+	r->type = (rtm->rtm_flags & RTF_REJECT) ? 2 : 4;
 
 	/* cannot really know, what protocol it runs */
 	r->proto = (rtm->rtm_flags & RTF_LOCAL) ? 2 :

contrib/ipfilter/ipsend/44arp.c

@@ -88,7 +88,12 @@ char	*addr, *eaddr;
 	mib[2] = 0;
 	mib[3] = AF_INET;
 	mib[4] = NET_RT_FLAGS;
+#ifdef RTF_LLINFO
 	mib[5] = RTF_LLINFO;
+#else
+	mib[5] = 0;
+#endif	
+
 	if (sysctl(mib, 6, NULL, &needed, NULL, 0) == -1)
 	    {
 		perror("route-sysctl-estimate");

lib/libstand/if_ether.h

@@ -156,7 +156,7 @@ struct	ifqueue arpintrq;
 void	arpwhohas(struct arpcom *, struct in_addr *);
 void	arpintr(void);
 int	arpresolve(struct arpcom *,
-	    struct rtentry *, struct mbuf *, struct sockaddr *, u_char *);
+	    struct rtentry *, struct mbuf *, struct sockaddr *, u_char *, struct llentry **);
 void	arp_ifinit(struct arpcom *, struct ifaddr *);
 void	arp_rtrequest(int, struct rtentry *, struct sockaddr *);
 
@@ -233,7 +233,7 @@ struct ether_multistep {
 #ifdef _KERNEL
 void arp_rtrequest(int, struct rtentry *, struct sockaddr *);
 int arpresolve(struct arpcom *, struct rtentry *, struct mbuf *,
-		    struct sockaddr *, u_char *);
+		    struct sockaddr *, u_char *, struct llentry **);
 void arpintr(void);
 int arpioctl(u_long, caddr_t);
 void arp_ifinit(struct arpcom *, struct ifaddr *);

libexec/bootpd/rtmsg.c

@@ -152,7 +152,6 @@ int bsd_arp_set(ia, eaddr, len)
 	sdl = (struct sockaddr_dl *)(sin->sin_len + (char *)sin);
 	if (sin->sin_addr.s_addr == sin_m.sin_addr.s_addr) {
 		if (sdl->sdl_family == AF_LINK &&
-		    (rtm->rtm_flags & RTF_LLINFO) &&
 		    !(rtm->rtm_flags & RTF_GATEWAY)) switch (sdl->sdl_type) {
 		case IFT_ETHER: case IFT_FDDI: case IFT_ISO88023:
 		case IFT_ISO88024: case IFT_ISO88025:

release/picobsd/tinyware/ns/ns.c

@@ -382,10 +382,6 @@ print_routing(char *proto)
 		rtm = (struct rt_msghdr *)next;
 		sa = (struct sockaddr *)(rtm + 1);
 		get_rtaddrs(rtm->rtm_addrs, sa, rti_info);
-		if (rtm->rtm_flags & RTF_WASCLONED) {
-			if ((rtm->rtm_flags & RTF_LLINFO) == 0)
-				continue;
-		}
 		if ((sa = rti_info[RTAX_DST]) != NULL) {
 			sprintf(fbuf, "%s", sock_ntop(sa, sa->sa_len));
 			if (((sa1 = rti_info[RTAX_NETMASK]) != NULL)

sbin/route/route.c

@@ -605,9 +605,6 @@ newroute(argc, argv)
 			case K_NOSTATIC:
 				flags &= ~RTF_STATIC;
 				break;
-			case K_LLINFO:
-				flags |= RTF_LLINFO;
-				break;
 			case K_LOCK:
 				locking = 1;
 				break;
@@ -632,9 +629,6 @@ newroute(argc, argv)
 			case K_PROXY:
 				proxy = 1;
 				break;
-			case K_CLONING:
-				flags |= RTF_CLONING;
-				break;
 			case K_XRESOLVE:
 				flags |= RTF_XRESOLVE;
 				break;

sbin/routed/table.c

@@ -1103,12 +1103,13 @@ flush_kern(void)
 		    || INFO_DST(&info)->sa_family != AF_INET)
 			continue;
 
+#if defined (RTF_LLINFO)		
 		/* ignore ARP table entries on systems with a merged route
 		 * and ARP table.
 		 */
 		if (rtm->rtm_flags & RTF_LLINFO)
 			continue;
-
+#endif
 #if defined(RTF_WASCLONED) && defined(__FreeBSD__)
 		/* ignore cloned routes
 		 */
@@ -1261,11 +1262,13 @@ read_rt(void)
 			continue;
 		}
 
+#if defined(RTF_LLINFO) 
 		if (m.r.rtm.rtm_flags & RTF_LLINFO) {
 			trace_act("ignore ARP %s", str);
 			continue;
 		}
-
+#endif
+
 #if defined(RTF_WASCLONED) && defined(__FreeBSD__)
 		if (m.r.rtm.rtm_flags & RTF_WASCLONED) {
 			trace_act("ignore cloned %s", str);

share/man/man4/route.4

@@ -196,7 +196,7 @@ Messages include:
 #define	RTM_REDIRECT	0x6    /* Told to use different route */
 #define	RTM_MISS	0x7    /* Lookup failed on this address */
 #define	RTM_LOCK	0x8    /* fix specified metrics */
-#define	RTM_RESOLVE	0xb    /* request to resolve dst to LL addr */
+#define	RTM_RESOLVE	0xb    /* request to resolve dst to LL addr - unused */
 #define	RTM_NEWADDR	0xc    /* address being added to iface */
 #define	RTM_DELADDR	0xd    /* address being removed from iface */
 #define	RTM_IFINFO	0xe    /* iface going up/down etc. */
@@ -308,7 +308,7 @@ Specifiers for which addresses are present in the messages are:
 #define RTA_DST       0x1    /* destination sockaddr present */
 #define RTA_GATEWAY   0x2    /* gateway sockaddr present */
 #define RTA_NETMASK   0x4    /* netmask sockaddr present */
-#define RTA_GENMASK   0x8    /* cloning mask sockaddr present */
+#define RTA_GENMASK   0x8    /* cloning mask sockaddr present - unused */
 #define RTA_IFP       0x10   /* interface name sockaddr present */
 #define RTA_IFA       0x20   /* interface addr sockaddr present */
 #define RTA_AUTHOR    0x40   /* sockaddr for author of redirect */

share/man/man9/rtalloc.9

@@ -27,7 +27,8 @@
 .\" SUCH DAMAGE.
 .\"
 .\" $FreeBSD$
-.Dd October 11, 2004
+.\"
+.Dd December 11, 2008
 .Os
 .Dt RTALLOC 9
 .Sh NAME
@@ -64,21 +65,6 @@ certain protocol\- and interface-specific actions to take place.
 .\" XXX - -mdoc should contain a standard request for getting em and
 .\" en dashes.
 .Pp
-When a route with the flag
-.Dv RTF_CLONING
-is retrieved, and the action of this flag is not masked, the
-.Nm
-facility automatically generates a new route using information in the
-old route as a template, and
-sends an
-.Dv RTM_RESOLVE
-message to the appropriate interface-address route-management routine
-.Pq Fn ifa->ifa_rtrequest .
-This generated route is called
-.Em cloned ,
-and has
-.Dv RTF_WASCLONED
-flag set.
 .Dv RTF_PRCLONING
 flag is obsolete and thus ignored by facility.
 If the
@@ -123,22 +109,19 @@ field.
 .Pp
 The
 .Fn rtalloc_ign
-interface can be used when the default actions of
-.Fn rtalloc
-in the presence of the
-.Dv RTF_CLONING
-flag is undesired.
+interface can be used when the caller does not want to receive
+the returned
+.Fa rtentry
+locked.
 The
 .Fa ro
 argument is the same as
 .Fn rtalloc ,
 but there is additionally a
 .Fa flags
-argument, which lists the flags in the route which are to be
-.Em ignored
-(in most cases this is
-.Dv RTF_CLONING
-flag).
+argument, which is now only used to pass
+.Dv RTF_RNH_LOCKED
+indicating that the radix tree lock is already held.
 Both
 .Fn rtalloc
 and
@@ -163,16 +146,7 @@ directly as the
 argument.
 The second argument,
 .Fa report ,
-controls whether
-.Dv RTM_RESOLVE
-requests are sent to the lower layers when an
-.Dv RTF_CLONING
-or
-.Dv RTF_PRCLONING
-route is cloned.
-Ordinarily a value of one should be passed, except
-in the processing of those lower layers which use the cloning
-facility.
+controls whether the lower layers are notified when a lookup fails.
 The third argument,
 .Fa flags ,
 is a set of flags to ignore, as in