Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
new file mode 100644
index 0000000..029362d
--- /dev/null
+++ b/net/ipv4/fib_semantics.c
@@ -0,0 +1,1332 @@
+/*
+ * INET		An implementation of the TCP/IP protocol suite for the LINUX
+ *		operating system.  INET is implemented using the  BSD Socket
+ *		interface as the means of communication with the user level.
+ *
+ *		IPv4 Forwarding Information Base: semantics.
+ *
+ * Version:	$Id: fib_semantics.c,v 1.19 2002/01/12 07:54:56 davem Exp $
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ *		This program is free software; you can redistribute it and/or
+ *		modify it under the terms of the GNU General Public License
+ *		as published by the Free Software Foundation; either version
+ *		2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/errno.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/proc_fs.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/init.h>
+
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/route.h>
+#include <net/tcp.h>
+#include <net/sock.h>
+#include <net/ip_fib.h>
+#include <net/ip_mp_alg.h>
+
+#include "fib_lookup.h"
+
+#define FSprintk(a...)
+
+static DEFINE_RWLOCK(fib_info_lock);
+static struct hlist_head *fib_info_hash;
+static struct hlist_head *fib_info_laddrhash;
+static unsigned int fib_hash_size;
+static unsigned int fib_info_cnt;
+
+#define DEVINDEX_HASHBITS 8
+#define DEVINDEX_HASHSIZE (1U << DEVINDEX_HASHBITS)
+static struct hlist_head fib_info_devhash[DEVINDEX_HASHSIZE];
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
+static DEFINE_SPINLOCK(fib_multipath_lock);
+
+#define for_nexthops(fi) { int nhsel; const struct fib_nh * nh; \
+for (nhsel=0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
+
+#define change_nexthops(fi) { int nhsel; struct fib_nh * nh; \
+for (nhsel=0, nh = (struct fib_nh*)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
+
+#else /* CONFIG_IP_ROUTE_MULTIPATH */
+
+/* Hope, that gcc will optimize it to get rid of dummy loop */
+
+#define for_nexthops(fi) { int nhsel=0; const struct fib_nh * nh = (fi)->fib_nh; \
+for (nhsel=0; nhsel < 1; nhsel++)
+
+#define change_nexthops(fi) { int nhsel=0; struct fib_nh * nh = (struct fib_nh*)((fi)->fib_nh); \
+for (nhsel=0; nhsel < 1; nhsel++)
+
+#endif /* CONFIG_IP_ROUTE_MULTIPATH */
+
+#define endfor_nexthops(fi) }
+
+
+static struct 
+{
+	int	error;
+	u8	scope;
+} fib_props[RTA_MAX + 1] = {
+        {
+		.error	= 0,
+		.scope	= RT_SCOPE_NOWHERE,
+	},	/* RTN_UNSPEC */
+	{
+		.error	= 0,
+		.scope	= RT_SCOPE_UNIVERSE,
+	},	/* RTN_UNICAST */
+	{
+		.error	= 0,
+		.scope	= RT_SCOPE_HOST,
+	},	/* RTN_LOCAL */
+	{
+		.error	= 0,
+		.scope	= RT_SCOPE_LINK,
+	},	/* RTN_BROADCAST */
+	{
+		.error	= 0,
+		.scope	= RT_SCOPE_LINK,
+	},	/* RTN_ANYCAST */
+	{
+		.error	= 0,
+		.scope	= RT_SCOPE_UNIVERSE,
+	},	/* RTN_MULTICAST */
+	{
+		.error	= -EINVAL,
+		.scope	= RT_SCOPE_UNIVERSE,
+	},	/* RTN_BLACKHOLE */
+	{
+		.error	= -EHOSTUNREACH,
+		.scope	= RT_SCOPE_UNIVERSE,
+	},	/* RTN_UNREACHABLE */
+	{
+		.error	= -EACCES,
+		.scope	= RT_SCOPE_UNIVERSE,
+	},	/* RTN_PROHIBIT */
+	{
+		.error	= -EAGAIN,
+		.scope	= RT_SCOPE_UNIVERSE,
+	},	/* RTN_THROW */
+	{
+		.error	= -EINVAL,
+		.scope	= RT_SCOPE_NOWHERE,
+	},	/* RTN_NAT */
+	{
+		.error	= -EINVAL,
+		.scope	= RT_SCOPE_NOWHERE,
+	},	/* RTN_XRESOLVE */
+};
+
+
+/* Release a nexthop info record */
+
+void free_fib_info(struct fib_info *fi)
+{
+	if (fi->fib_dead == 0) {
+		printk("Freeing alive fib_info %p\n", fi);
+		return;
+	}
+	change_nexthops(fi) {
+		if (nh->nh_dev)
+			dev_put(nh->nh_dev);
+		nh->nh_dev = NULL;
+	} endfor_nexthops(fi);
+	fib_info_cnt--;
+	kfree(fi);
+}
+
+void fib_release_info(struct fib_info *fi)
+{
+	write_lock(&fib_info_lock);
+	if (fi && --fi->fib_treeref == 0) {
+		hlist_del(&fi->fib_hash);
+		if (fi->fib_prefsrc)
+			hlist_del(&fi->fib_lhash);
+		change_nexthops(fi) {
+			if (!nh->nh_dev)
+				continue;
+			hlist_del(&nh->nh_hash);
+		} endfor_nexthops(fi)
+		fi->fib_dead = 1;
+		fib_info_put(fi);
+	}
+	write_unlock(&fib_info_lock);
+}
+
+static __inline__ int nh_comp(const struct fib_info *fi, const struct fib_info *ofi)
+{
+	const struct fib_nh *onh = ofi->fib_nh;
+
+	for_nexthops(fi) {
+		if (nh->nh_oif != onh->nh_oif ||
+		    nh->nh_gw  != onh->nh_gw ||
+		    nh->nh_scope != onh->nh_scope ||
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+		    nh->nh_weight != onh->nh_weight ||
+#endif
+#ifdef CONFIG_NET_CLS_ROUTE
+		    nh->nh_tclassid != onh->nh_tclassid ||
+#endif
+		    ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
+			return -1;
+		onh++;
+	} endfor_nexthops(fi);
+	return 0;
+}
+
+static inline unsigned int fib_info_hashfn(const struct fib_info *fi)
+{
+	unsigned int mask = (fib_hash_size - 1);
+	unsigned int val = fi->fib_nhs;
+
+	val ^= fi->fib_protocol;
+	val ^= fi->fib_prefsrc;
+	val ^= fi->fib_priority;
+
+	return (val ^ (val >> 7) ^ (val >> 12)) & mask;
+}
+
+static struct fib_info *fib_find_info(const struct fib_info *nfi)
+{
+	struct hlist_head *head;
+	struct hlist_node *node;
+	struct fib_info *fi;
+	unsigned int hash;
+
+	hash = fib_info_hashfn(nfi);
+	head = &fib_info_hash[hash];
+
+	hlist_for_each_entry(fi, node, head, fib_hash) {
+		if (fi->fib_nhs != nfi->fib_nhs)
+			continue;
+		if (nfi->fib_protocol == fi->fib_protocol &&
+		    nfi->fib_prefsrc == fi->fib_prefsrc &&
+		    nfi->fib_priority == fi->fib_priority &&
+		    memcmp(nfi->fib_metrics, fi->fib_metrics,
+			   sizeof(fi->fib_metrics)) == 0 &&
+		    ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
+		    (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0))
+			return fi;
+	}
+
+	return NULL;
+}
+
+static inline unsigned int fib_devindex_hashfn(unsigned int val)
+{
+	unsigned int mask = DEVINDEX_HASHSIZE - 1;
+
+	return (val ^
+		(val >> DEVINDEX_HASHBITS) ^
+		(val >> (DEVINDEX_HASHBITS * 2))) & mask;
+}
+
+/* Check, that the gateway is already configured.
+   Used only by redirect accept routine.
+ */
+
+int ip_fib_check_default(u32 gw, struct net_device *dev)
+{
+	struct hlist_head *head;
+	struct hlist_node *node;
+	struct fib_nh *nh;
+	unsigned int hash;
+
+	read_lock(&fib_info_lock);
+
+	hash = fib_devindex_hashfn(dev->ifindex);
+	head = &fib_info_devhash[hash];
+	hlist_for_each_entry(nh, node, head, nh_hash) {
+		if (nh->nh_dev == dev &&
+		    nh->nh_gw == gw &&
+		    !(nh->nh_flags&RTNH_F_DEAD)) {
+			read_unlock(&fib_info_lock);
+			return 0;
+		}
+	}
+
+	read_unlock(&fib_info_lock);
+
+	return -1;
+}
+
+void rtmsg_fib(int event, u32 key, struct fib_alias *fa,
+	       int z, int tb_id,
+	       struct nlmsghdr *n, struct netlink_skb_parms *req)
+{
+	struct sk_buff *skb;
+	u32 pid = req ? req->pid : 0;
+	int size = NLMSG_SPACE(sizeof(struct rtmsg)+256);
+
+	skb = alloc_skb(size, GFP_KERNEL);
+	if (!skb)
+		return;
+
+	if (fib_dump_info(skb, pid, n->nlmsg_seq, event, tb_id,
+			  fa->fa_type, fa->fa_scope, &key, z,
+			  fa->fa_tos,
+			  fa->fa_info) < 0) {
+		kfree_skb(skb);
+		return;
+	}
+	NETLINK_CB(skb).dst_groups = RTMGRP_IPV4_ROUTE;
+	if (n->nlmsg_flags&NLM_F_ECHO)
+		atomic_inc(&skb->users);
+	netlink_broadcast(rtnl, skb, pid, RTMGRP_IPV4_ROUTE, GFP_KERNEL);
+	if (n->nlmsg_flags&NLM_F_ECHO)
+		netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
+}
+
+/* Return the first fib alias matching TOS with
+ * priority less than or equal to PRIO.
+ */
+struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio)
+{
+	if (fah) {
+		struct fib_alias *fa;
+		list_for_each_entry(fa, fah, fa_list) {
+			if (fa->fa_tos > tos)
+				continue;
+			if (fa->fa_info->fib_priority >= prio ||
+			    fa->fa_tos < tos)
+				return fa;
+		}
+	}
+	return NULL;
+}
+
+int fib_detect_death(struct fib_info *fi, int order,
+		     struct fib_info **last_resort, int *last_idx, int *dflt)
+{
+	struct neighbour *n;
+	int state = NUD_NONE;
+
+	n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev);
+	if (n) {
+		state = n->nud_state;
+		neigh_release(n);
+	}
+	if (state==NUD_REACHABLE)
+		return 0;
+	if ((state&NUD_VALID) && order != *dflt)
+		return 0;
+	if ((state&NUD_VALID) ||
+	    (*last_idx<0 && order > *dflt)) {
+		*last_resort = fi;
+		*last_idx = order;
+	}
+	return 1;
+}
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
+static u32 fib_get_attr32(struct rtattr *attr, int attrlen, int type)
+{
+	while (RTA_OK(attr,attrlen)) {
+		if (attr->rta_type == type)
+			return *(u32*)RTA_DATA(attr);
+		attr = RTA_NEXT(attr, attrlen);
+	}
+	return 0;
+}
+
+static int
+fib_count_nexthops(struct rtattr *rta)
+{
+	int nhs = 0;
+	struct rtnexthop *nhp = RTA_DATA(rta);
+	int nhlen = RTA_PAYLOAD(rta);
+
+	while (nhlen >= (int)sizeof(struct rtnexthop)) {
+		if ((nhlen -= nhp->rtnh_len) < 0)
+			return 0;
+		nhs++;
+		nhp = RTNH_NEXT(nhp);
+	};
+	return nhs;
+}
+
+static int
+fib_get_nhs(struct fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
+{
+	struct rtnexthop *nhp = RTA_DATA(rta);
+	int nhlen = RTA_PAYLOAD(rta);
+
+	change_nexthops(fi) {
+		int attrlen = nhlen - sizeof(struct rtnexthop);
+		if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
+			return -EINVAL;
+		nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
+		nh->nh_oif = nhp->rtnh_ifindex;
+		nh->nh_weight = nhp->rtnh_hops + 1;
+		if (attrlen) {
+			nh->nh_gw = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
+#ifdef CONFIG_NET_CLS_ROUTE
+			nh->nh_tclassid = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_FLOW);
+#endif
+		}
+		nhp = RTNH_NEXT(nhp);
+	} endfor_nexthops(fi);
+	return 0;
+}
+
+#endif
+
+int fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct kern_rta *rta,
+		 struct fib_info *fi)
+{
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	struct rtnexthop *nhp;
+	int nhlen;
+#endif
+
+	if (rta->rta_priority &&
+	    *rta->rta_priority != fi->fib_priority)
+		return 1;
+
+	if (rta->rta_oif || rta->rta_gw) {
+		if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
+		    (!rta->rta_gw  || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 4) == 0))
+			return 0;
+		return 1;
+	}
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	if (rta->rta_mp == NULL)
+		return 0;
+	nhp = RTA_DATA(rta->rta_mp);
+	nhlen = RTA_PAYLOAD(rta->rta_mp);
+	
+	for_nexthops(fi) {
+		int attrlen = nhlen - sizeof(struct rtnexthop);
+		u32 gw;
+
+		if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
+			return -EINVAL;
+		if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
+			return 1;
+		if (attrlen) {
+			gw = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
+			if (gw && gw != nh->nh_gw)
+				return 1;
+#ifdef CONFIG_NET_CLS_ROUTE
+			gw = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_FLOW);
+			if (gw && gw != nh->nh_tclassid)
+				return 1;
+#endif
+		}
+		nhp = RTNH_NEXT(nhp);
+	} endfor_nexthops(fi);
+#endif
+	return 0;
+}
+
+
+/*
+   Picture
+   -------
+
+   Semantics of nexthop is very messy by historical reasons.
+   We have to take into account, that:
+   a) gateway can be actually local interface address,
+      so that gatewayed route is direct.
+   b) gateway must be on-link address, possibly
+      described not by an ifaddr, but also by a direct route.
+   c) If both gateway and interface are specified, they should not
+      contradict.
+   d) If we use tunnel routes, gateway could be not on-link.
+
+   Attempt to reconcile all of these (alas, self-contradictory) conditions
+   results in pretty ugly and hairy code with obscure logic.
+
+   I chose to generalized it instead, so that the size
+   of code does not increase practically, but it becomes
+   much more general.
+   Every prefix is assigned a "scope" value: "host" is local address,
+   "link" is direct route,
+   [ ... "site" ... "interior" ... ]
+   and "universe" is true gateway route with global meaning.
+
+   Every prefix refers to a set of "nexthop"s (gw, oif),
+   where gw must have narrower scope. This recursion stops
+   when gw has LOCAL scope or if "nexthop" is declared ONLINK,
+   which means that gw is forced to be on link.
+
+   Code is still hairy, but now it is apparently logically
+   consistent and very flexible. F.e. as by-product it allows
+   to co-exists in peace independent exterior and interior
+   routing processes.
+
+   Normally it looks as following.
+
+   {universe prefix}  -> (gw, oif) [scope link]
+                          |
+			  |-> {link prefix} -> (gw, oif) [scope local]
+			                        |
+						|-> {local prefix} (terminal node)
+ */
+
+static int fib_check_nh(const struct rtmsg *r, struct fib_info *fi, struct fib_nh *nh)
+{
+	int err;
+
+	if (nh->nh_gw) {
+		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;
+
+			if (r->rtm_scope >= RT_SCOPE_LINK)
+				return -EINVAL;
+			if (inet_addr_type(nh->nh_gw) != RTN_UNICAST)
+				return -EINVAL;
+			if ((dev = __dev_get_by_index(nh->nh_oif)) == NULL)
+				return -ENODEV;
+			if (!(dev->flags&IFF_UP))
+				return -ENETDOWN;
+			nh->nh_dev = dev;
+			dev_hold(dev);
+			nh->nh_scope = RT_SCOPE_LINK;
+			return 0;
+		}
+		{
+			struct flowi fl = { .nl_u = { .ip4_u =
+						      { .daddr = nh->nh_gw,
+							.scope = r->rtm_scope + 1 } },
+					    .oif = nh->nh_oif };
+
+			/* It is not necessary, but requires a bit of thinking */
+			if (fl.fl4_scope < RT_SCOPE_LINK)
+				fl.fl4_scope = RT_SCOPE_LINK;
+			if ((err = fib_lookup(&fl, &res)) != 0)
+				return err;
+		}
+		err = -EINVAL;
+		if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
+			goto out;
+		nh->nh_scope = res.scope;
+		nh->nh_oif = FIB_RES_OIF(res);
+		if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL)
+			goto out;
+		dev_hold(nh->nh_dev);
+		err = -ENETDOWN;
+		if (!(nh->nh_dev->flags & IFF_UP))
+			goto out;
+		err = 0;
+out:
+		fib_res_put(&res);
+		return err;
+	} else {
+		struct in_device *in_dev;
+
+		if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
+			return -EINVAL;
+
+		in_dev = inetdev_by_index(nh->nh_oif);
+		if (in_dev == NULL)
+			return -ENODEV;
+		if (!(in_dev->dev->flags&IFF_UP)) {
+			in_dev_put(in_dev);
+			return -ENETDOWN;
+		}
+		nh->nh_dev = in_dev->dev;
+		dev_hold(nh->nh_dev);
+		nh->nh_scope = RT_SCOPE_HOST;
+		in_dev_put(in_dev);
+	}
+	return 0;
+}
+
+static inline unsigned int fib_laddr_hashfn(u32 val)
+{
+	unsigned int mask = (fib_hash_size - 1);
+
+	return (val ^ (val >> 7) ^ (val >> 14)) & mask;
+}
+
+static struct hlist_head *fib_hash_alloc(int bytes)
+{
+	if (bytes <= PAGE_SIZE)
+		return kmalloc(bytes, GFP_KERNEL);
+	else
+		return (struct hlist_head *)
+			__get_free_pages(GFP_KERNEL, get_order(bytes));
+}
+
+static void fib_hash_free(struct hlist_head *hash, int bytes)
+{
+	if (!hash)
+		return;
+
+	if (bytes <= PAGE_SIZE)
+		kfree(hash);
+	else
+		free_pages((unsigned long) hash, get_order(bytes));
+}
+
+static void fib_hash_move(struct hlist_head *new_info_hash,
+			  struct hlist_head *new_laddrhash,
+			  unsigned int new_size)
+{
+	unsigned int old_size = fib_hash_size;
+	unsigned int i;
+
+	write_lock(&fib_info_lock);
+	fib_hash_size = new_size;
+
+	for (i = 0; i < old_size; i++) {
+		struct hlist_head *head = &fib_info_hash[i];
+		struct hlist_node *node, *n;
+		struct fib_info *fi;
+
+		hlist_for_each_entry_safe(fi, node, n, head, fib_hash) {
+			struct hlist_head *dest;
+			unsigned int new_hash;
+
+			hlist_del(&fi->fib_hash);
+
+			new_hash = fib_info_hashfn(fi);
+			dest = &new_info_hash[new_hash];
+			hlist_add_head(&fi->fib_hash, dest);
+		}
+	}
+	fib_info_hash = new_info_hash;
+
+	for (i = 0; i < old_size; i++) {
+		struct hlist_head *lhead = &fib_info_laddrhash[i];
+		struct hlist_node *node, *n;
+		struct fib_info *fi;
+
+		hlist_for_each_entry_safe(fi, node, n, lhead, fib_lhash) {
+			struct hlist_head *ldest;
+			unsigned int new_hash;
+
+			hlist_del(&fi->fib_lhash);
+
+			new_hash = fib_laddr_hashfn(fi->fib_prefsrc);
+			ldest = &new_laddrhash[new_hash];
+			hlist_add_head(&fi->fib_lhash, ldest);
+		}
+	}
+	fib_info_laddrhash = new_laddrhash;
+
+	write_unlock(&fib_info_lock);
+}
+
+struct fib_info *
+fib_create_info(const struct rtmsg *r, struct kern_rta *rta,
+		const struct nlmsghdr *nlh, int *errp)
+{
+	int err;
+	struct fib_info *fi = NULL;
+	struct fib_info *ofi;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	int nhs = 1;
+#else
+	const int nhs = 1;
+#endif
+#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
+	u32 mp_alg = IP_MP_ALG_NONE;
+#endif
+
+	/* Fast check to catch the most weird cases */
+	if (fib_props[r->rtm_type].scope > r->rtm_scope)
+		goto err_inval;
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	if (rta->rta_mp) {
+		nhs = fib_count_nexthops(rta->rta_mp);
+		if (nhs == 0)
+			goto err_inval;
+	}
+#endif
+#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
+	if (rta->rta_mp_alg) {
+		mp_alg = *rta->rta_mp_alg;
+
+		if (mp_alg < IP_MP_ALG_NONE ||
+		    mp_alg > IP_MP_ALG_MAX)
+			goto err_inval;
+	}
+#endif
+
+	err = -ENOBUFS;
+	if (fib_info_cnt >= fib_hash_size) {
+		unsigned int new_size = fib_hash_size << 1;
+		struct hlist_head *new_info_hash;
+		struct hlist_head *new_laddrhash;
+		unsigned int bytes;
+
+		if (!new_size)
+			new_size = 1;
+		bytes = new_size * sizeof(struct hlist_head *);
+		new_info_hash = fib_hash_alloc(bytes);
+		new_laddrhash = fib_hash_alloc(bytes);
+		if (!new_info_hash || !new_laddrhash) {
+			fib_hash_free(new_info_hash, bytes);
+			fib_hash_free(new_laddrhash, bytes);
+		} else {
+			memset(new_info_hash, 0, bytes);
+			memset(new_laddrhash, 0, bytes);
+
+			fib_hash_move(new_info_hash, new_laddrhash, new_size);
+		}
+
+		if (!fib_hash_size)
+			goto failure;
+	}
+
+	fi = kmalloc(sizeof(*fi)+nhs*sizeof(struct fib_nh), GFP_KERNEL);
+	if (fi == NULL)
+		goto failure;
+	fib_info_cnt++;
+	memset(fi, 0, sizeof(*fi)+nhs*sizeof(struct fib_nh));
+
+	fi->fib_protocol = r->rtm_protocol;
+
+	fi->fib_nhs = nhs;
+	change_nexthops(fi) {
+		nh->nh_parent = fi;
+	} endfor_nexthops(fi)
+
+	fi->fib_flags = r->rtm_flags;
+	if (rta->rta_priority)
+		fi->fib_priority = *rta->rta_priority;
+	if (rta->rta_mx) {
+		int attrlen = RTA_PAYLOAD(rta->rta_mx);
+		struct rtattr *attr = RTA_DATA(rta->rta_mx);
+
+		while (RTA_OK(attr, attrlen)) {
+			unsigned flavor = attr->rta_type;
+			if (flavor) {
+				if (flavor > RTAX_MAX)
+					goto err_inval;
+				fi->fib_metrics[flavor-1] = *(unsigned*)RTA_DATA(attr);
+			}
+			attr = RTA_NEXT(attr, attrlen);
+		}
+	}
+	if (rta->rta_prefsrc)
+		memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 4);
+
+	if (rta->rta_mp) {
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+		if ((err = fib_get_nhs(fi, rta->rta_mp, r)) != 0)
+			goto failure;
+		if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
+			goto err_inval;
+		if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 4))
+			goto err_inval;
+#ifdef CONFIG_NET_CLS_ROUTE
+		if (rta->rta_flow && memcmp(&fi->fib_nh->nh_tclassid, rta->rta_flow, 4))
+			goto err_inval;
+#endif
+#else
+		goto err_inval;
+#endif
+	} else {
+		struct fib_nh *nh = fi->fib_nh;
+		if (rta->rta_oif)
+			nh->nh_oif = *rta->rta_oif;
+		if (rta->rta_gw)
+			memcpy(&nh->nh_gw, rta->rta_gw, 4);
+#ifdef CONFIG_NET_CLS_ROUTE
+		if (rta->rta_flow)
+			memcpy(&nh->nh_tclassid, rta->rta_flow, 4);
+#endif
+		nh->nh_flags = r->rtm_flags;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+		nh->nh_weight = 1;
+#endif
+	}
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
+	fi->fib_mp_alg = mp_alg;
+#endif
+
+	if (fib_props[r->rtm_type].error) {
+		if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
+			goto err_inval;
+		goto link_it;
+	}
+
+	if (r->rtm_scope > RT_SCOPE_HOST)
+		goto err_inval;
+
+	if (r->rtm_scope == RT_SCOPE_HOST) {
+		struct fib_nh *nh = fi->fib_nh;
+
+		/* Local address is added. */
+		if (nhs != 1 || nh->nh_gw)
+			goto err_inval;
+		nh->nh_scope = RT_SCOPE_NOWHERE;
+		nh->nh_dev = dev_get_by_index(fi->fib_nh->nh_oif);
+		err = -ENODEV;
+		if (nh->nh_dev == NULL)
+			goto failure;
+	} else {
+		change_nexthops(fi) {
+			if ((err = fib_check_nh(r, fi, nh)) != 0)
+				goto failure;
+		} endfor_nexthops(fi)
+	}
+
+	if (fi->fib_prefsrc) {
+		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)
+				goto err_inval;
+	}
+
+link_it:
+	if ((ofi = fib_find_info(fi)) != NULL) {
+		fi->fib_dead = 1;
+		free_fib_info(fi);
+		ofi->fib_treeref++;
+		return ofi;
+	}
+
+	fi->fib_treeref++;
+	atomic_inc(&fi->fib_clntref);
+	write_lock(&fib_info_lock);
+	hlist_add_head(&fi->fib_hash,
+		       &fib_info_hash[fib_info_hashfn(fi)]);
+	if (fi->fib_prefsrc) {
+		struct hlist_head *head;
+
+		head = &fib_info_laddrhash[fib_laddr_hashfn(fi->fib_prefsrc)];
+		hlist_add_head(&fi->fib_lhash, head);
+	}
+	change_nexthops(fi) {
+		struct hlist_head *head;
+		unsigned int hash;
+
+		if (!nh->nh_dev)
+			continue;
+		hash = fib_devindex_hashfn(nh->nh_dev->ifindex);
+		head = &fib_info_devhash[hash];
+		hlist_add_head(&nh->nh_hash, head);
+	} endfor_nexthops(fi)
+	write_unlock(&fib_info_lock);
+	return fi;
+
+err_inval:
+	err = -EINVAL;
+
+failure:
+        *errp = err;
+        if (fi) {
+		fi->fib_dead = 1;
+		free_fib_info(fi);
+	}
+	return NULL;
+}
+
+int fib_semantic_match(struct list_head *head, const struct flowi *flp,
+		       struct fib_result *res, __u32 zone, __u32 mask, 
+			int prefixlen)
+{
+	struct fib_alias *fa;
+	int nh_sel = 0;
+
+	list_for_each_entry(fa, head, fa_list) {
+		int err;
+
+		if (fa->fa_tos &&
+		    fa->fa_tos != flp->fl4_tos)
+			continue;
+
+		if (fa->fa_scope < flp->fl4_scope)
+			continue;
+
+		fa->fa_state |= FA_S_ACCESSED;
+
+		err = fib_props[fa->fa_type].error;
+		if (err == 0) {
+			struct fib_info *fi = fa->fa_info;
+
+			if (fi->fib_flags & RTNH_F_DEAD)
+				continue;
+
+			switch (fa->fa_type) {
+			case RTN_UNICAST:
+			case RTN_LOCAL:
+			case RTN_BROADCAST:
+			case RTN_ANYCAST:
+			case RTN_MULTICAST:
+				for_nexthops(fi) {
+					if (nh->nh_flags&RTNH_F_DEAD)
+						continue;
+					if (!flp->oif || flp->oif == nh->nh_oif)
+						break;
+				}
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+				if (nhsel < fi->fib_nhs) {
+					nh_sel = nhsel;
+					goto out_fill_res;
+				}
+#else
+				if (nhsel < 1) {
+					goto out_fill_res;
+				}
+#endif
+				endfor_nexthops(fi);
+				continue;
+
+			default:
+				printk(KERN_DEBUG "impossible 102\n");
+				return -EINVAL;
+			};
+		}
+		return err;
+	}
+	return 1;
+
+out_fill_res:
+	res->prefixlen = prefixlen;
+	res->nh_sel = nh_sel;
+	res->type = fa->fa_type;
+	res->scope = fa->fa_scope;
+	res->fi = fa->fa_info;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
+	res->netmask = mask;
+	res->network = zone &
+		(0xFFFFFFFF >> (32 - prefixlen));
+#endif
+	atomic_inc(&res->fi->fib_clntref);
+	return 0;
+}
+
+/* Find appropriate source address to this destination */
+
+u32 __fib_res_prefsrc(struct fib_result *res)
+{
+	return inet_select_addr(FIB_RES_DEV(*res), FIB_RES_GW(*res), res->scope);
+}
+
+int
+fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
+	      u8 tb_id, u8 type, u8 scope, void *dst, int dst_len, u8 tos,
+	      struct fib_info *fi)
+{
+	struct rtmsg *rtm;
+	struct nlmsghdr  *nlh;
+	unsigned char	 *b = skb->tail;
+
+	nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*rtm));
+	rtm = NLMSG_DATA(nlh);
+	rtm->rtm_family = AF_INET;
+	rtm->rtm_dst_len = dst_len;
+	rtm->rtm_src_len = 0;
+	rtm->rtm_tos = tos;
+	rtm->rtm_table = tb_id;
+	rtm->rtm_type = type;
+	rtm->rtm_flags = fi->fib_flags;
+	rtm->rtm_scope = scope;
+	if (rtm->rtm_dst_len)
+		RTA_PUT(skb, RTA_DST, 4, dst);
+	rtm->rtm_protocol = fi->fib_protocol;
+	if (fi->fib_priority)
+		RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
+#ifdef CONFIG_NET_CLS_ROUTE
+	if (fi->fib_nh[0].nh_tclassid)
+		RTA_PUT(skb, RTA_FLOW, 4, &fi->fib_nh[0].nh_tclassid);
+#endif
+	if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
+		goto rtattr_failure;
+	if (fi->fib_prefsrc)
+		RTA_PUT(skb, RTA_PREFSRC, 4, &fi->fib_prefsrc);
+	if (fi->fib_nhs == 1) {
+		if (fi->fib_nh->nh_gw)
+			RTA_PUT(skb, RTA_GATEWAY, 4, &fi->fib_nh->nh_gw);
+		if (fi->fib_nh->nh_oif)
+			RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
+	}
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+	if (fi->fib_nhs > 1) {
+		struct rtnexthop *nhp;
+		struct rtattr *mp_head;
+		if (skb_tailroom(skb) <= RTA_SPACE(0))
+			goto rtattr_failure;
+		mp_head = (struct rtattr*)skb_put(skb, RTA_SPACE(0));
+
+		for_nexthops(fi) {
+			if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
+				goto rtattr_failure;
+			nhp = (struct rtnexthop*)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
+			nhp->rtnh_flags = nh->nh_flags & 0xFF;
+			nhp->rtnh_hops = nh->nh_weight-1;
+			nhp->rtnh_ifindex = nh->nh_oif;
+			if (nh->nh_gw)
+				RTA_PUT(skb, RTA_GATEWAY, 4, &nh->nh_gw);
+			nhp->rtnh_len = skb->tail - (unsigned char*)nhp;
+		} endfor_nexthops(fi);
+		mp_head->rta_type = RTA_MULTIPATH;
+		mp_head->rta_len = skb->tail - (u8*)mp_head;
+	}
+#endif
+	nlh->nlmsg_len = skb->tail - b;
+	return skb->len;
+
+nlmsg_failure:
+rtattr_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+#ifndef CONFIG_IP_NOSIOCRT
+
+int
+fib_convert_rtentry(int cmd, struct nlmsghdr *nl, struct rtmsg *rtm,
+		    struct kern_rta *rta, struct rtentry *r)
+{
+	int    plen;
+	u32    *ptr;
+
+	memset(rtm, 0, sizeof(*rtm));
+	memset(rta, 0, sizeof(*rta));
+
+	if (r->rt_dst.sa_family != AF_INET)
+		return -EAFNOSUPPORT;
+
+	/* Check mask for validity:
+	   a) it must be contiguous.
+	   b) destination must have all host bits clear.
+	   c) if application forgot to set correct family (AF_INET),
+	      reject request unless it is absolutely clear i.e.
+	      both family and mask are zero.
+	 */
+	plen = 32;
+	ptr = &((struct sockaddr_in*)&r->rt_dst)->sin_addr.s_addr;
+	if (!(r->rt_flags&RTF_HOST)) {
+		u32 mask = ((struct sockaddr_in*)&r->rt_genmask)->sin_addr.s_addr;
+		if (r->rt_genmask.sa_family != AF_INET) {
+			if (mask || r->rt_genmask.sa_family)
+				return -EAFNOSUPPORT;
+		}
+		if (bad_mask(mask, *ptr))
+			return -EINVAL;
+		plen = inet_mask_len(mask);
+	}
+
+	nl->nlmsg_flags = NLM_F_REQUEST;
+	nl->nlmsg_pid = 0;
+	nl->nlmsg_seq = 0;
+	nl->nlmsg_len = NLMSG_LENGTH(sizeof(*rtm));
+	if (cmd == SIOCDELRT) {
+		nl->nlmsg_type = RTM_DELROUTE;
+		nl->nlmsg_flags = 0;
+	} else {
+		nl->nlmsg_type = RTM_NEWROUTE;
+		nl->nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE;
+		rtm->rtm_protocol = RTPROT_BOOT;
+	}
+
+	rtm->rtm_dst_len = plen;
+	rta->rta_dst = ptr;
+
+	if (r->rt_metric) {
+		*(u32*)&r->rt_pad3 = r->rt_metric - 1;
+		rta->rta_priority = (u32*)&r->rt_pad3;
+	}
+	if (r->rt_flags&RTF_REJECT) {
+		rtm->rtm_scope = RT_SCOPE_HOST;
+		rtm->rtm_type = RTN_UNREACHABLE;
+		return 0;
+	}
+	rtm->rtm_scope = RT_SCOPE_NOWHERE;
+	rtm->rtm_type = RTN_UNICAST;
+
+	if (r->rt_dev) {
+		char *colon;
+		struct net_device *dev;
+		char   devname[IFNAMSIZ];
+
+		if (copy_from_user(devname, r->rt_dev, IFNAMSIZ-1))
+			return -EFAULT;
+		devname[IFNAMSIZ-1] = 0;
+		colon = strchr(devname, ':');
+		if (colon)
+			*colon = 0;
+		dev = __dev_get_by_name(devname);
+		if (!dev)
+			return -ENODEV;
+		rta->rta_oif = &dev->ifindex;
+		if (colon) {
+			struct in_ifaddr *ifa;
+			struct in_device *in_dev = __in_dev_get(dev);
+			if (!in_dev)
+				return -ENODEV;
+			*colon = ':';
+			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
+				if (strcmp(ifa->ifa_label, devname) == 0)
+					break;
+			if (ifa == NULL)
+				return -ENODEV;
+			rta->rta_prefsrc = &ifa->ifa_local;
+		}
+	}
+
+	ptr = &((struct sockaddr_in*)&r->rt_gateway)->sin_addr.s_addr;
+	if (r->rt_gateway.sa_family == AF_INET && *ptr) {
+		rta->rta_gw = ptr;
+		if (r->rt_flags&RTF_GATEWAY && inet_addr_type(*ptr) == RTN_UNICAST)
+			rtm->rtm_scope = RT_SCOPE_UNIVERSE;
+	}
+
+	if (cmd == SIOCDELRT)
+		return 0;
+
+	if (r->rt_flags&RTF_GATEWAY && rta->rta_gw == NULL)
+		return -EINVAL;
+
+	if (rtm->rtm_scope == RT_SCOPE_NOWHERE)
+		rtm->rtm_scope = RT_SCOPE_LINK;
+
+	if (r->rt_flags&(RTF_MTU|RTF_WINDOW|RTF_IRTT)) {
+		struct rtattr *rec;
+		struct rtattr *mx = kmalloc(RTA_LENGTH(3*RTA_LENGTH(4)), GFP_KERNEL);
+		if (mx == NULL)
+			return -ENOMEM;
+		rta->rta_mx = mx;
+		mx->rta_type = RTA_METRICS;
+		mx->rta_len  = RTA_LENGTH(0);
+		if (r->rt_flags&RTF_MTU) {
+			rec = (void*)((char*)mx + RTA_ALIGN(mx->rta_len));
+			rec->rta_type = RTAX_ADVMSS;
+			rec->rta_len = RTA_LENGTH(4);
+			mx->rta_len += RTA_LENGTH(4);
+			*(u32*)RTA_DATA(rec) = r->rt_mtu - 40;
+		}
+		if (r->rt_flags&RTF_WINDOW) {
+			rec = (void*)((char*)mx + RTA_ALIGN(mx->rta_len));
+			rec->rta_type = RTAX_WINDOW;
+			rec->rta_len = RTA_LENGTH(4);
+			mx->rta_len += RTA_LENGTH(4);
+			*(u32*)RTA_DATA(rec) = r->rt_window;
+		}
+		if (r->rt_flags&RTF_IRTT) {
+			rec = (void*)((char*)mx + RTA_ALIGN(mx->rta_len));
+			rec->rta_type = RTAX_RTT;
+			rec->rta_len = RTA_LENGTH(4);
+			mx->rta_len += RTA_LENGTH(4);
+			*(u32*)RTA_DATA(rec) = r->rt_irtt<<3;
+		}
+	}
+	return 0;
+}
+
+#endif
+
+/*
+   Update FIB if:
+   - local address disappeared -> we must delete all the entries
+     referring to it.
+   - device went down -> we must shutdown all nexthops going via it.
+ */
+
+int fib_sync_down(u32 local, struct net_device *dev, int force)
+{
+	int ret = 0;
+	int scope = RT_SCOPE_NOWHERE;
+	
+	if (force)
+		scope = -1;
+
+	if (local && fib_info_laddrhash) {
+		unsigned int hash = fib_laddr_hashfn(local);
+		struct hlist_head *head = &fib_info_laddrhash[hash];
+		struct hlist_node *node;
+		struct fib_info *fi;
+
+		hlist_for_each_entry(fi, node, head, fib_lhash) {
+			if (fi->fib_prefsrc == local) {
+				fi->fib_flags |= RTNH_F_DEAD;
+				ret++;
+			}
+		}
+	}
+
+	if (dev) {
+		struct fib_info *prev_fi = NULL;
+		unsigned int hash = fib_devindex_hashfn(dev->ifindex);
+		struct hlist_head *head = &fib_info_devhash[hash];
+		struct hlist_node *node;
+		struct fib_nh *nh;
+
+		hlist_for_each_entry(nh, node, head, nh_hash) {
+			struct fib_info *fi = nh->nh_parent;
+			int dead;
+
+			BUG_ON(!fi->fib_nhs);
+			if (nh->nh_dev != dev || fi == prev_fi)
+				continue;
+			prev_fi = fi;
+			dead = 0;
+			change_nexthops(fi) {
+				if (nh->nh_flags&RTNH_F_DEAD)
+					dead++;
+				else if (nh->nh_dev == dev &&
+					 nh->nh_scope != scope) {
+					nh->nh_flags |= RTNH_F_DEAD;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+					spin_lock_bh(&fib_multipath_lock);
+					fi->fib_power -= nh->nh_power;
+					nh->nh_power = 0;
+					spin_unlock_bh(&fib_multipath_lock);
+#endif
+					dead++;
+				}
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+				if (force > 1 && nh->nh_dev == dev) {
+					dead = fi->fib_nhs;
+					break;
+				}
+#endif
+			} endfor_nexthops(fi)
+			if (dead == fi->fib_nhs) {
+				fi->fib_flags |= RTNH_F_DEAD;
+				ret++;
+			}
+		}
+	}
+
+	return ret;
+}
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
+/*
+   Dead device goes up. We wake up dead nexthops.
+   It takes sense only on multipath routes.
+ */
+
+int fib_sync_up(struct net_device *dev)
+{
+	struct fib_info *prev_fi;
+	unsigned int hash;
+	struct hlist_head *head;
+	struct hlist_node *node;
+	struct fib_nh *nh;
+	int ret;
+
+	if (!(dev->flags&IFF_UP))
+		return 0;
+
+	prev_fi = NULL;
+	hash = fib_devindex_hashfn(dev->ifindex);
+	head = &fib_info_devhash[hash];
+	ret = 0;
+
+	hlist_for_each_entry(nh, node, head, nh_hash) {
+		struct fib_info *fi = nh->nh_parent;
+		int alive;
+
+		BUG_ON(!fi->fib_nhs);
+		if (nh->nh_dev != dev || fi == prev_fi)
+			continue;
+
+		prev_fi = fi;
+		alive = 0;
+		change_nexthops(fi) {
+			if (!(nh->nh_flags&RTNH_F_DEAD)) {
+				alive++;
+				continue;
+			}
+			if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
+				continue;
+			if (nh->nh_dev != dev || __in_dev_get(dev) == NULL)
+				continue;
+			alive++;
+			spin_lock_bh(&fib_multipath_lock);
+			nh->nh_power = 0;
+			nh->nh_flags &= ~RTNH_F_DEAD;
+			spin_unlock_bh(&fib_multipath_lock);
+		} endfor_nexthops(fi)
+
+		if (alive > 0) {
+			fi->fib_flags &= ~RTNH_F_DEAD;
+			ret++;
+		}
+	}
+
+	return ret;
+}
+
+/*
+   The algorithm is suboptimal, but it provides really
+   fair weighted route distribution.
+ */
+
+void fib_select_multipath(const struct flowi *flp, struct fib_result *res)
+{
+	struct fib_info *fi = res->fi;
+	int w;
+
+	spin_lock_bh(&fib_multipath_lock);
+	if (fi->fib_power <= 0) {
+		int power = 0;
+		change_nexthops(fi) {
+			if (!(nh->nh_flags&RTNH_F_DEAD)) {
+				power += nh->nh_weight;
+				nh->nh_power = nh->nh_weight;
+			}
+		} endfor_nexthops(fi);
+		fi->fib_power = power;
+		if (power <= 0) {
+			spin_unlock_bh(&fib_multipath_lock);
+			/* Race condition: route has just become dead. */
+			res->nh_sel = 0;
+			return;
+		}
+	}
+
+
+	/* w should be random number [0..fi->fib_power-1],
+	   it is pretty bad approximation.
+	 */
+
+	w = jiffies % fi->fib_power;
+
+	change_nexthops(fi) {
+		if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
+			if ((w -= nh->nh_power) <= 0) {
+				nh->nh_power--;
+				fi->fib_power--;
+				res->nh_sel = nhsel;
+				spin_unlock_bh(&fib_multipath_lock);
+				return;
+			}
+		}
+	} endfor_nexthops(fi);
+
+	/* Race condition: route has just become dead. */
+	res->nh_sel = 0;
+	spin_unlock_bh(&fib_multipath_lock);
+}
+#endif