route.generic

VRRP双机热备份协议源吗

 			fib_disable_ip(ifa->ifa_dev->dev, 1);
 		} else {
+			printk("fib_inetaddr_event: dev down, fib_del_ifaddr\n");
 			fib_del_ifaddr(ifa);
 			rt_cache_flush(-1);
 		}
@@ -606,11 +665,10 @@
 	struct net_device *dev = ptr;
 	struct in_device *in_dev = __in_dev_get(dev);
 
-	if (!in_dev)
-		return NOTIFY_DONE;
-
 	switch (event) {
 	case NETDEV_UP:
+		if (!in_dev)
+			break;
 		for_ifa(in_dev) {
 			fib_add_ifaddr(ifa);
 		} endfor_ifa(in_dev);
@@ -620,9 +678,18 @@
 		rt_cache_flush(-1);
 		break;
 	case NETDEV_DOWN:
+		printk("fib_netdev_event: dev down, fib_disable_ip(0)\n");
 		fib_disable_ip(dev, 0);
 		break;
 	case NETDEV_UNREGISTER:
+		/* Routes pointing to dev may still exists even when IP has
+		 * been shut down.  It may happen because routes of local type
+		 * has special nexthop (see fib_create_info() and
+		 * fib_sync_dev_down()).  I don't know if this state is valid.
+		 * Now I call fib_disable_ip() independently from if the device
+		 * has IP because otherwise stale device references are left.
+		 * 1999/11/28  SAW */
+		printk("fib_netdev_event: dev unregister, fib_disable_ip(1)\n");
 		fib_disable_ip(dev, 1);
 		break;
 	case NETDEV_CHANGEMTU:
diff -ru -x*~ linux-lt-2.3.99-pre3.prev/net/ipv4/fib_semantics.c linux-lt-2.3.99-pre3/net/ipv4/fib_semantics.c
--- linux-lt-2.3.99-pre3.prev/net/ipv4/fib_semantics.c	Tue Aug 24 01:01:02 1999
+++ linux-lt-2.3.99-pre3/net/ipv4/fib_semantics.c	Tue Mar 28 19:39:50 2000
@@ -345,14 +345,15 @@
 {
 	int err;
 
+	if (nh->nh_flags&RTNH_F_PERVASIVE) {
+		fi->fib_flags |= RTCF_PERVASIVE;
+		return 0;
+	}
+
 	if (nh->nh_gw) {
 		struct rt_key key;
 		struct fib_result res;
 
-#ifdef CONFIG_IP_ROUTE_PERVASIVE
-		if (nh->nh_flags&RTNH_F_PERVASIVE)
-			return 0;
-#endif
 		if (nh->nh_flags&RTNH_F_ONLINK) {
 			struct net_device *dev;
 
@@ -389,7 +390,7 @@
 	} else {
 		struct in_device *in_dev;
 
-		if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
+		if (nh->nh_flags&RTNH_F_ONLINK)
 			return -EINVAL;
 
 		in_dev = inetdev_by_index(nh->nh_oif);
@@ -528,7 +529,7 @@
 		} endfor_nexthops(fi)
 	}
 
-	if (fi->fib_prefsrc) {
+	if (fi->fib_prefsrc && !(fi->fib_flags&RTCF_PERVASIVE)) {
 		if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
 		    memcmp(&fi->fib_prefsrc, rta->rta_dst, 4))
 			if (inet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
@@ -857,19 +858,34 @@
    - device went down -> we must shutdown all nexthops going via it.
  */
 
-int fib_sync_down(u32 local, struct net_device *dev, int force)
+int fib_sync_addr_down(u32 local)
+{
+	int ret = 0;
+
+	if (!local)
+		goto out;
+
+	for_fib_info() {
+		if (fi->fib_prefsrc == local &&
+				!(fi->fib_flags&RTCF_PERVASIVE)) {
+			fi->fib_flags |= RTCF_DEAD;
+			ret++;
+		}
+	} endfor_fib_info();
+out:
+	return ret;
+}
+
+int fib_sync_dev_down(struct net_device *dev, int force)
 {
 	int ret = 0;
 	int scope = RT_SCOPE_NOWHERE;
-	
+
 	if (force)
 		scope = -1;
 
 	for_fib_info() {
-		if (local && fi->fib_prefsrc == local) {
-			fi->fib_flags |= RTNH_F_DEAD;
-			ret++;
-		} else if (dev && fi->fib_nhs) {
+		if (fi->fib_nhs) {
 			int dead = 0;
 
 			change_nexthops(fi) {
@@ -886,7 +902,7 @@
 				}
 			} endfor_nexthops(fi)
 			if (dead == fi->fib_nhs) {
-				fi->fib_flags |= RTNH_F_DEAD;
+				fi->fib_flags |= RTCF_DEAD;
 				ret++;
 			}
 		}
@@ -947,6 +963,10 @@
 		int power = 0;
 		change_nexthops(fi) {
 			if (!(nh->nh_flags&RTNH_F_DEAD)) {
+				if (nh->nh_flags&RTNH_F_USEFIRST) {
+					res->nh_sel = nhsel;
+					return;
+				}
 				power += nh->nh_weight;
 				nh->nh_power = nh->nh_weight;
 			}
diff -ru -x*~ linux-lt-2.3.99-pre3.prev/net/ipv4/route.c linux-lt-2.3.99-pre3/net/ipv4/route.c
--- linux-lt-2.3.99-pre3.prev/net/ipv4/route.c	Mon Mar 27 18:25:56 2000
+++ linux-lt-2.3.99-pre3/net/ipv4/route.c	Tue Mar 28 19:57:19 2000
@@ -711,22 +711,28 @@
 	struct rtable *rth, **rthp;
 	u32  skeys[2] = { saddr, 0 };
 	int  ikeys[2] = { dev->ifindex, 0 };
+	char *reason;
 
 	tos &= IPTOS_TOS_MASK;
 
 	if (!in_dev)
 		return;
 
+	reason = "bad gateway";
 	if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev)
 	    || MULTICAST(new_gw) || BADCLASS(new_gw) || ZERONET(new_gw))
 		goto reject_redirect;
 
 	if (!IN_DEV_SHARED_MEDIA(in_dev)) {
-		if (!inet_addr_onlink(in_dev, new_gw, old_gw))
+		reason = "gateway not onlink";
+		if (!inet_addr_onlink(dev, new_gw, saddr, tos))
 			goto reject_redirect;
-		if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
+		reason = "insecure gateway";
+		if (IN_DEV_SEC_REDIRECTS(in_dev) &&
+				ip_fib_check_default(new_gw, dev))
 			goto reject_redirect;
 	} else {
+		reason = "unacceptable gateway";
 		if (inet_addr_type(new_gw) != RTN_UNICAST)
 			goto reject_redirect;
 	}
@@ -816,9 +822,9 @@
 reject_redirect:
 #ifdef CONFIG_IP_ROUTE_VERBOSE
 	if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
-		printk(KERN_INFO "Redirect from %X/%s to %X ignored."
+		printk(KERN_INFO "Redirect from %X/%s to %X ignored (%s). "
 		       "Path = %X -> %X, tos %02x\n",
-		       ntohl(old_gw), dev->name, ntohl(new_gw),
+		       ntohl(old_gw), dev->name, ntohl(new_gw), reason,
 		       ntohl(saddr), ntohl(daddr), tos);
 #endif
 	in_dev_put(in_dev);
@@ -836,7 +842,7 @@
 		if ((rt->rt_flags&RTCF_REDIRECTED) || rt->u.dst.expires) {
 			unsigned hash = rt_hash_code(rt->key.dst, rt->key.src^(rt->key.oif<<5), rt->key.tos);
 #if RT_CACHE_DEBUG >= 1
-			printk(KERN_DEBUG "ip_rt_advice: redirect to %d.%d.%d.%d/%02x dropped\n", NIPQUAD(rt->rt_dst), rt->key.tos);
+			printk(KERN_DEBUG "ip_rt_advice: cache entry to %d.%d.%d.%d/%02x dropped\n", NIPQUAD(rt->rt_dst), rt->key.tos);
 #endif
 			rt_del(hash, rt);
 			return NULL;
@@ -1106,6 +1112,10 @@
 }
 #endif
 
+/*********************************************************************
+			 Input/output routing
+ *********************************************************************/
+
 static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag)
 {
 	struct fib_info *fi = res->fi;
@@ -1145,6 +1155,10 @@
         rt->rt_type = res->type;
 }
 
+/*********************************************************************
+				Input
+ *********************************************************************/
+
 static int
 ip_route_input_mc(struct sk_buff *skb, u32 daddr, u32 saddr,
 		  u8 tos, struct net_device *dev, int our)
@@ -1362,9 +1376,7 @@
 	if (err)
 		flags |= RTCF_DIRECTSRC;
 
-	if (out_dev == in_dev && err && !(flags&(RTCF_NAT|RTCF_MASQ)) &&
-	    (IN_DEV_SHARED_MEDIA(out_dev)
-	     || inet_addr_onlink(out_dev, saddr, FIB_RES_GW(res))))
+	if (out_dev == in_dev && err && !(flags&(RTCF_NAT|RTCF_MASQ)))
 		flags |= RTCF_DOREDIRECT;
 
 	if (skb->protocol != __constant_htons(ETH_P_IP)) {
@@ -1592,22 +1604,183 @@
 	return ip_route_input_slow(skb, daddr, saddr, tos, dev);
 }
 
+/*********************************************************************
+				Output
+ *********************************************************************/
+
+/* TODO:
+    - Check if CONFIG_IP_MROUTE ifdef makes any sense.
+ */
+
+/* User supplied source address verification for output packets.
+   Such a verification can't be considered as a security measure.
+   It's rather an additional Internet protection against bugs in applications
+   (like using an uninitialized garbage as a source for UDP packets).
+ */
+static int outrt_check_src(u32 saddr, u32 daddr, u32 tos, struct net_device *dev_out)
+{
+	struct in_device	*in_dev;
+	int			src_check;
+
+	if (MULTICAST(saddr) || BADCLASS(saddr) || ZERONET(saddr))
+		return -EINVAL;
+	if (saddr == htonl(INADDR_BROADCAST))
+		return -EINVAL;
+
+	in_dev = in_dev_get(dev_out);
+	src_check = IN_DEV_SRC_CHECK(in_dev);
+	in_dev_put(in_dev);
+	if (!src_check)
+		return 0;
+
+	if (LOOPBACK(saddr) && !(dev_out->flags&IFF_LOOPBACK))
+		return -EINVAL;
+
+	return fib_local_source(saddr, daddr, tos, dev_out);
+}
+
+static int outrt_make_route(struct rtable **rp,
+	/* route lookup key */
+	struct rt_key *key,
+	/* path */
+	u32 daddr, u32 saddr, struct net_device *dev_out,
+	/* FIB lookup results (type, fi, nh.gw, nh.scope) */
+	struct fib_result *res
+	)
+{
+	struct rtable *rth;
+	unsigned hash;
+	unsigned flags;
+
+	rth = dst_alloc(&ipv4_dst_ops);
+	if (!rth)
+		return -ENOBUFS;
+
+	atomic_set(&rth->u.dst.__refcnt, 1);
+	rth->u.dst.flags= DST_HOST;
+	rth->key	= *key;
+	rth->key.iif	= 0; /* output route */
+	rth->rt_dst	= daddr;
+	rth->rt_src	= saddr;
+#ifdef CONFIG_IP_ROUTE_NAT
+	rth->rt_dst_map	= daddr;
+	rth->rt_src_map	= saddr;
+#endif
+
+	/* Set input, output ROUTINES and rt_spec_dst */
+	switch (res->type) {
+		case RTN_LOCAL:
+			/* Use loopback interface for unicast local traffic */
+			fib_res_put(res);
+			res->fi = NULL;
+#ifdef CONFIG_IP_MULTIPLE_TABLES
+			res->r = NULL;
+#endif
+			dev_out = &loopback_dev;
+			flags = RTCF_LOCAL;
+			rth->u.dst.input  = ip_local_deliver;
+			rth->u.dst.output = ip_output;
+			rth->rt_spec_dst  = daddr; /* local side of the path */
+			break;
+		case RTN_UNICAST:
+			flags = 0;
+			rth->u.dst.output = ip_output;
+			rth->rt_spec_dst  = saddr;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+			if (res->fi->fib_nhs > 1 && key->oif == 0)
+				/* Set the proper res->nh_sel. */
+				fib_select_multipath(key, res);
+			else
+#endif
+			if (res->prefixlen == 0 && res->type == RTN_UNICAST &&
+					key->oif == 0)
+				fib_select_default(key, res);
+			break;
+		case RTN_BROADCAST:
+			flags = RTCF_BROADCAST|RTCF_LOCAL;
+			rth->u.dst.input  = ip_local_deliver;
+			if (!(dev_out->flags&IFF_LOOPBACK))
+				rth->u.dst.output = ip_mc_output;
+			else
+				rth->u.dst.output = ip_output;
+			rth->rt_spec_dst  = saddr;
+			break;
+		case RTN_MULTICAST:
+			{
+			/* Please note that all ancient band-aids were removed.
+			   I don't try to catch route table deficient for
+			   multicast or 255.255.255.255 routes and "smartly"
+			   replace a gatewayed default by the corresponding
+			   route.  1999/11/06  SAW
+			 */
+			struct in_device *in_dev = in_dev_get(dev_out);
+			rth->u.dst.input  = ip_local_deliver;
+			rth->u.dst.output = ip_output;
+			flags = RTCF_MULTICAST;
+			if (in_dev && ip_check_mc(in_dev, daddr)) {
+				/* Note: I preserve the original behaviour
+				   here.  It means that users after joining and
+				   leaving a multicast group have to flush
+				   the route cache.  I hope they know about it
+				   :-)  1999/11/06  SAW
+				 */
+				flags = RTCF_MULTICAST|RTCF_LOCAL;
+				if (!(dev_out->flags&IFF_LOOPBACK))
+					rth->u.dst.output = ip_mc_output;
+			}
+#ifdef CONFIG_IP_MROUTE
+			if (in_dev && !(dev_out->flags&IFF_LOOPBACK)) {
+				if (IN_DEV_MFORWARD(in_dev) &&
+						!LOCAL_MCAST(daddr))
+				{
+					rth->u.dst.input = ip_mr_input;
+					rth->u.dst.output = ip_mc_output;
+				}
+			}
+#endif
+			if (in_dev)
+				in_dev_put(in_dev);
+			rth->rt_spec_dst  = saddr;
+			}
+			break;
+		case RTN_NAT:
+			dst_free(&rth->u.dst);
+			return -EINVAL;
+		default:
+			printk(KERN_CRIT "bad lookup result type in route output\n");