net/ipv4/fib_rules.c - fp2-dev/kernel/msm - Gitiles

 /*
  * 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: policy rules.
  *
  * Version:	$Id: fib_rules.c,v 1.17 2001/10/31 21:55:54 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.
  *
  * Fixes:
  * 		Rani Assaf	:	local_rule cannot be deleted
  *		Marc Boucher	:	routing by fwmark
  */

 #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/sched.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>

 #define FRprintk(a...)

 struct fib_rule
 {
 	struct fib_rule *r_next;
 	atomic_t	r_clntref;
 	u32		r_preference;
 	unsigned char	r_table;
 	unsigned char	r_action;
 	unsigned char	r_dst_len;
 	unsigned char	r_src_len;
 	u32		r_src;
 	u32		r_srcmask;
 	u32		r_dst;
 	u32		r_dstmask;
 	u32		r_srcmap;
 	u8		r_flags;
 	u8		r_tos;
 #ifdef CONFIG_IP_ROUTE_FWMARK
 	u32		r_fwmark;
 #endif
 	int		r_ifindex;
 #ifdef CONFIG_NET_CLS_ROUTE
 	__u32		r_tclassid;
 #endif
 	char		r_ifname[IFNAMSIZ];
 	int		r_dead;
 };

 static struct fib_rule default_rule = {
 	.r_clntref =	ATOMIC_INIT(2),
 	.r_preference =	0x7FFF,
 	.r_table =	RT_TABLE_DEFAULT,
 	.r_action =	RTN_UNICAST,
 };

 static struct fib_rule main_rule = {
 	.r_next =	&default_rule,
 	.r_clntref =	ATOMIC_INIT(2),
 	.r_preference =	0x7FFE,
 	.r_table =	RT_TABLE_MAIN,
 	.r_action =	RTN_UNICAST,
 };

 static struct fib_rule local_rule = {
 	.r_next =	&main_rule,
 	.r_clntref =	ATOMIC_INIT(2),
 	.r_table =	RT_TABLE_LOCAL,
 	.r_action =	RTN_UNICAST,
 };

 static struct fib_rule *fib_rules = &local_rule;
 static DEFINE_RWLOCK(fib_rules_lock);

 int inet_rtm_delrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
 	struct rtattr **rta = arg;
 	struct rtmsg *rtm = NLMSG_DATA(nlh);
 	struct fib_rule *r, **rp;
 	int err = -ESRCH;

 	for (rp=&fib_rules; (r=*rp) != NULL; rp=&r->r_next) {
 		if ((!rta[RTA_SRC-1] || memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 4) == 0) &&
 		    rtm->rtm_src_len == r->r_src_len &&
 		    rtm->rtm_dst_len == r->r_dst_len &&
 		    (!rta[RTA_DST-1] || memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 4) == 0) &&
 		    rtm->rtm_tos == r->r_tos &&
 #ifdef CONFIG_IP_ROUTE_FWMARK
 		    (!rta[RTA_PROTOINFO-1] || memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&
 #endif
 		    (!rtm->rtm_type || rtm->rtm_type == r->r_action) &&
 		    (!rta[RTA_PRIORITY-1] || memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&
 		    (!rta[RTA_IIF-1] || rtattr_strcmp(rta[RTA_IIF-1], r->r_ifname) == 0) &&
 		    (!rtm->rtm_table || (r && rtm->rtm_table == r->r_table))) {
 			err = -EPERM;
 			if (r == &local_rule)
 				break;

 			write_lock_bh(&fib_rules_lock);
 			*rp = r->r_next;
 			r->r_dead = 1;
 			write_unlock_bh(&fib_rules_lock);
 			fib_rule_put(r);
 			err = 0;
 			break;
 		}
 	}
 	return err;
 }

 /* Allocate new unique table id */

 static struct fib_table *fib_empty_table(void)
 {
 	int id;

 	for (id = 1; id <= RT_TABLE_MAX; id++)
 		if (fib_tables[id] == NULL)
 			return __fib_new_table(id);
 	return NULL;
 }

 void fib_rule_put(struct fib_rule *r)
 {
 	if (atomic_dec_and_test(&r->r_clntref)) {
 		if (r->r_dead)
 			kfree(r);
 		else
 			printk("Freeing alive rule %p\n", r);
 	}
 }

 int inet_rtm_newrule(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 {
 	struct rtattr **rta = arg;
 	struct rtmsg *rtm = NLMSG_DATA(nlh);
 	struct fib_rule *r, *new_r, **rp;
 	unsigned char table_id;

 	if (rtm->rtm_src_len > 32 || rtm->rtm_dst_len > 32 ||
 	    (rtm->rtm_tos & ~IPTOS_TOS_MASK))
 		return -EINVAL;

 	if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)
 		return -EINVAL;

 	table_id = rtm->rtm_table;
 	if (table_id == RT_TABLE_UNSPEC) {
 		struct fib_table *table;
 		if (rtm->rtm_type == RTN_UNICAST) {
 			if ((table = fib_empty_table()) == NULL)
 				return -ENOBUFS;
 			table_id = table->tb_id;
 		}
 	}

 	new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);
 	if (!new_r)
 		return -ENOMEM;
 	memset(new_r, 0, sizeof(*new_r));
 	if (rta[RTA_SRC-1])
 		memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 4);
 	if (rta[RTA_DST-1])
 		memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 4);
 	if (rta[RTA_GATEWAY-1])
 		memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 4);
 	new_r->r_src_len = rtm->rtm_src_len;
 	new_r->r_dst_len = rtm->rtm_dst_len;
 	new_r->r_srcmask = inet_make_mask(rtm->rtm_src_len);
 	new_r->r_dstmask = inet_make_mask(rtm->rtm_dst_len);
 	new_r->r_tos = rtm->rtm_tos;
 #ifdef CONFIG_IP_ROUTE_FWMARK
 	if (rta[RTA_PROTOINFO-1])
 		memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);
 #endif
 	new_r->r_action = rtm->rtm_type;
 	new_r->r_flags = rtm->rtm_flags;
 	if (rta[RTA_PRIORITY-1])
 		memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);
 	new_r->r_table = table_id;
 	if (rta[RTA_IIF-1]) {
 		struct net_device *dev;
 		rtattr_strlcpy(new_r->r_ifname, rta[RTA_IIF-1], IFNAMSIZ);
 		new_r->r_ifindex = -1;
 		dev = __dev_get_by_name(new_r->r_ifname);
 		if (dev)
 			new_r->r_ifindex = dev->ifindex;
 	}
 #ifdef CONFIG_NET_CLS_ROUTE
 	if (rta[RTA_FLOW-1])
 		memcpy(&new_r->r_tclassid, RTA_DATA(rta[RTA_FLOW-1]), 4);
 #endif

 	rp = &fib_rules;
 	if (!new_r->r_preference) {
 		r = fib_rules;
 		if (r && (r = r->r_next) != NULL) {
 			rp = &fib_rules->r_next;
 			if (r->r_preference)
 				new_r->r_preference = r->r_preference - 1;
 		}
 	}

 	while ( (r = *rp) != NULL ) {
 		if (r->r_preference > new_r->r_preference)
 			break;
 		rp = &r->r_next;
 	}

 	new_r->r_next = r;
 	atomic_inc(&new_r->r_clntref);
 	write_lock_bh(&fib_rules_lock);
 	*rp = new_r;
 	write_unlock_bh(&fib_rules_lock);
 	return 0;
 }

 #ifdef CONFIG_NET_CLS_ROUTE
 u32 fib_rules_tclass(struct fib_result *res)
 {
 	if (res->r)
 		return res->r->r_tclassid;
 	return 0;
 }
 #endif


 static void fib_rules_detach(struct net_device *dev)
 {
 	struct fib_rule *r;

 	for (r=fib_rules; r; r=r->r_next) {
 		if (r->r_ifindex == dev->ifindex) {
 			write_lock_bh(&fib_rules_lock);
 			r->r_ifindex = -1;
 			write_unlock_bh(&fib_rules_lock);
 		}
 	}
 }

 static void fib_rules_attach(struct net_device *dev)
 {
 	struct fib_rule *r;

 	for (r=fib_rules; r; r=r->r_next) {
 		if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0) {
 			write_lock_bh(&fib_rules_lock);
 			r->r_ifindex = dev->ifindex;
 			write_unlock_bh(&fib_rules_lock);
 		}
 	}
 }

 int fib_lookup(const struct flowi *flp, struct fib_result *res)
 {
 	int err;
 	struct fib_rule *r, *policy;
 	struct fib_table *tb;

 	u32 daddr = flp->fl4_dst;
 	u32 saddr = flp->fl4_src;

 FRprintk("Lookup: %u.%u.%u.%u <- %u.%u.%u.%u ",
 	NIPQUAD(flp->fl4_dst), NIPQUAD(flp->fl4_src));
 	read_lock(&fib_rules_lock);
 	for (r = fib_rules; r; r=r->r_next) {
 		if (((saddr^r->r_src) & r->r_srcmask) ||
 		    ((daddr^r->r_dst) & r->r_dstmask) ||
 		    (r->r_tos && r->r_tos != flp->fl4_tos) ||
 #ifdef CONFIG_IP_ROUTE_FWMARK
 		    (r->r_fwmark && r->r_fwmark != flp->fl4_fwmark) ||
 #endif
 		    (r->r_ifindex && r->r_ifindex != flp->iif))
 			continue;

 FRprintk("tb %d r %d ", r->r_table, r->r_action);
 		switch (r->r_action) {
 		case RTN_UNICAST:
 			policy = r;
 			break;
 		case RTN_UNREACHABLE:
 			read_unlock(&fib_rules_lock);
 			return -ENETUNREACH;
 		default:
 		case RTN_BLACKHOLE:
 			read_unlock(&fib_rules_lock);
 			return -EINVAL;
 		case RTN_PROHIBIT:
 			read_unlock(&fib_rules_lock);
 			return -EACCES;
 		}

 		if ((tb = fib_get_table(r->r_table)) == NULL)
 			continue;
 		err = tb->tb_lookup(tb, flp, res);
 		if (err == 0) {
 			res->r = policy;
 			if (policy)
 				atomic_inc(&policy->r_clntref);
 			read_unlock(&fib_rules_lock);
 			return 0;
 		}
 		if (err < 0 && err != -EAGAIN) {
 			read_unlock(&fib_rules_lock);
 			return err;
 		}
 	}
 FRprintk("FAILURE\n");
 	read_unlock(&fib_rules_lock);
 	return -ENETUNREACH;
 }

 void fib_select_default(const struct flowi *flp, struct fib_result *res)
 {
 	if (res->r && res->r->r_action == RTN_UNICAST &&
 	    FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) {
 		struct fib_table *tb;
 		if ((tb = fib_get_table(res->r->r_table)) != NULL)
 			tb->tb_select_default(tb, flp, res);
 	}
 }

 static int fib_rules_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
 	struct net_device *dev = ptr;

 	if (event == NETDEV_UNREGISTER)
 		fib_rules_detach(dev);
 	else if (event == NETDEV_REGISTER)
 		fib_rules_attach(dev);
 	return NOTIFY_DONE;
 }


 static struct notifier_block fib_rules_notifier = {
 	.notifier_call =fib_rules_event,
 };

 static __inline__ int inet_fill_rule(struct sk_buff *skb,
 				     struct fib_rule *r,
 				     struct netlink_callback *cb,
 				     unsigned int flags)
 {
 	struct rtmsg *rtm;
 	struct nlmsghdr  *nlh;
 	unsigned char	 *b = skb->tail;

 	nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWRULE, sizeof(*rtm), flags);
 	rtm = NLMSG_DATA(nlh);
 	rtm->rtm_family = AF_INET;
 	rtm->rtm_dst_len = r->r_dst_len;
 	rtm->rtm_src_len = r->r_src_len;
 	rtm->rtm_tos = r->r_tos;
 #ifdef CONFIG_IP_ROUTE_FWMARK
 	if (r->r_fwmark)
 		RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);
 #endif
 	rtm->rtm_table = r->r_table;
 	rtm->rtm_protocol = 0;
 	rtm->rtm_scope = 0;
 	rtm->rtm_type = r->r_action;
 	rtm->rtm_flags = r->r_flags;

 	if (r->r_dst_len)
 		RTA_PUT(skb, RTA_DST, 4, &r->r_dst);
 	if (r->r_src_len)
 		RTA_PUT(skb, RTA_SRC, 4, &r->r_src);
 	if (r->r_ifname[0])
 		RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);
 	if (r->r_preference)
 		RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);
 	if (r->r_srcmap)
 		RTA_PUT(skb, RTA_GATEWAY, 4, &r->r_srcmap);
 #ifdef CONFIG_NET_CLS_ROUTE
 	if (r->r_tclassid)
 		RTA_PUT(skb, RTA_FLOW, 4, &r->r_tclassid);
 #endif
 	nlh->nlmsg_len = skb->tail - b;
 	return skb->len;

 nlmsg_failure:
 rtattr_failure:
 	skb_trim(skb, b - skb->data);
 	return -1;
 }

 int inet_dump_rules(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	int idx;
 	int s_idx = cb->args[0];
 	struct fib_rule *r;

 	read_lock(&fib_rules_lock);
 	for (r=fib_rules, idx=0; r; r = r->r_next, idx++) {
 		if (idx < s_idx)
 			continue;
 		if (inet_fill_rule(skb, r, cb, NLM_F_MULTI) < 0)
 			break;
 	}
 	read_unlock(&fib_rules_lock);
 	cb->args[0] = idx;

 	return skb->len;
 }

 void __init fib_rules_init(void)
 {
 	register_netdevice_notifier(&fib_rules_notifier);
 }
	/*
	* 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: policy rules.
	*
	* Version: $Id: fib_rules.c,v 1.17 2001/10/31 21:55:54 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.
	*
	* Fixes:
	* Rani Assaf : local_rule cannot be deleted
	* Marc Boucher : routing by fwmark
	*/

	#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/sched.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>

	#define FRprintk(a...)

	struct fib_rule
	{
	struct fib_rule *r_next;
	atomic_t r_clntref;
	u32 r_preference;
	unsigned char r_table;
	unsigned char r_action;
	unsigned char r_dst_len;
	unsigned char r_src_len;
	u32 r_src;
	u32 r_srcmask;
	u32 r_dst;
	u32 r_dstmask;
	u32 r_srcmap;
	u8 r_flags;
	u8 r_tos;
	#ifdef CONFIG_IP_ROUTE_FWMARK
	u32 r_fwmark;
	#endif
	int r_ifindex;
	#ifdef CONFIG_NET_CLS_ROUTE
	__u32 r_tclassid;
	#endif
	char r_ifname[IFNAMSIZ];
	int r_dead;
	};

	static struct fib_rule default_rule = {
	.r_clntref = ATOMIC_INIT(2),
	.r_preference = 0x7FFF,
	.r_table = RT_TABLE_DEFAULT,
	.r_action = RTN_UNICAST,
	};

	static struct fib_rule main_rule = {
	.r_next = &default_rule,
	.r_clntref = ATOMIC_INIT(2),
	.r_preference = 0x7FFE,
	.r_table = RT_TABLE_MAIN,
	.r_action = RTN_UNICAST,
	};

	static struct fib_rule local_rule = {
	.r_next = &main_rule,
	.r_clntref = ATOMIC_INIT(2),
	.r_table = RT_TABLE_LOCAL,
	.r_action = RTN_UNICAST,
	};

	static struct fib_rule *fib_rules = &local_rule;
	static DEFINE_RWLOCK(fib_rules_lock);

	int inet_rtm_delrule(struct sk_buff skb, struct nlmsghdr nlh, void *arg)
	{
	struct rtattr **rta = arg;
	struct rtmsg *rtm = NLMSG_DATA(nlh);
	struct fib_rule r, *rp;
	int err = -ESRCH;

	for (rp=&fib_rules; (r=*rp) != NULL; rp=&r->r_next) {
	if ((!rta[RTA_SRC-1] \|\| memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 4) == 0) &&
	rtm->rtm_src_len == r->r_src_len &&
	rtm->rtm_dst_len == r->r_dst_len &&
	(!rta[RTA_DST-1] \|\| memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 4) == 0) &&
	rtm->rtm_tos == r->r_tos &&
	#ifdef CONFIG_IP_ROUTE_FWMARK
	(!rta[RTA_PROTOINFO-1] \|\| memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&
	#endif
	(!rtm->rtm_type \|\| rtm->rtm_type == r->r_action) &&
	(!rta[RTA_PRIORITY-1] \|\| memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&
	(!rta[RTA_IIF-1] \|\| rtattr_strcmp(rta[RTA_IIF-1], r->r_ifname) == 0) &&
	(!rtm->rtm_table \|\| (r && rtm->rtm_table == r->r_table))) {
	err = -EPERM;
	if (r == &local_rule)
	break;

	write_lock_bh(&fib_rules_lock);
	*rp = r->r_next;
	r->r_dead = 1;
	write_unlock_bh(&fib_rules_lock);
	fib_rule_put(r);
	err = 0;
	break;
	}
	}
	return err;
	}

	/* Allocate new unique table id */

	static struct fib_table *fib_empty_table(void)
	{
	int id;

	for (id = 1; id <= RT_TABLE_MAX; id++)
	if (fib_tables[id] == NULL)
	return __fib_new_table(id);
	return NULL;
	}

	void fib_rule_put(struct fib_rule *r)
	{
	if (atomic_dec_and_test(&r->r_clntref)) {
	if (r->r_dead)
	kfree(r);
	else
	printk("Freeing alive rule %p\n", r);
	}
	}

	int inet_rtm_newrule(struct sk_buff skb, struct nlmsghdr nlh, void *arg)
	{
	struct rtattr **rta = arg;
	struct rtmsg *rtm = NLMSG_DATA(nlh);
	struct fib_rule r, new_r, **rp;
	unsigned char table_id;

	if (rtm->rtm_src_len > 32 \|\| rtm->rtm_dst_len > 32 \|\|
	(rtm->rtm_tos & ~IPTOS_TOS_MASK))
	return -EINVAL;

	if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)
	return -EINVAL;

	table_id = rtm->rtm_table;
	if (table_id == RT_TABLE_UNSPEC) {
	struct fib_table *table;
	if (rtm->rtm_type == RTN_UNICAST) {
	if ((table = fib_empty_table()) == NULL)
	return -ENOBUFS;
	table_id = table->tb_id;
	}
	}

	new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);
	if (!new_r)
	return -ENOMEM;
	memset(new_r, 0, sizeof(*new_r));
	if (rta[RTA_SRC-1])
	memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 4);
	if (rta[RTA_DST-1])
	memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 4);
	if (rta[RTA_GATEWAY-1])
	memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 4);
	new_r->r_src_len = rtm->rtm_src_len;
	new_r->r_dst_len = rtm->rtm_dst_len;
	new_r->r_srcmask = inet_make_mask(rtm->rtm_src_len);
	new_r->r_dstmask = inet_make_mask(rtm->rtm_dst_len);
	new_r->r_tos = rtm->rtm_tos;
	#ifdef CONFIG_IP_ROUTE_FWMARK
	if (rta[RTA_PROTOINFO-1])
	memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);
	#endif
	new_r->r_action = rtm->rtm_type;
	new_r->r_flags = rtm->rtm_flags;
	if (rta[RTA_PRIORITY-1])
	memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);
	new_r->r_table = table_id;
	if (rta[RTA_IIF-1]) {
	struct net_device *dev;
	rtattr_strlcpy(new_r->r_ifname, rta[RTA_IIF-1], IFNAMSIZ);
	new_r->r_ifindex = -1;
	dev = __dev_get_by_name(new_r->r_ifname);
	if (dev)
	new_r->r_ifindex = dev->ifindex;
	}
	#ifdef CONFIG_NET_CLS_ROUTE
	if (rta[RTA_FLOW-1])
	memcpy(&new_r->r_tclassid, RTA_DATA(rta[RTA_FLOW-1]), 4);
	#endif

	rp = &fib_rules;
	if (!new_r->r_preference) {
	r = fib_rules;
	if (r && (r = r->r_next) != NULL) {
	rp = &fib_rules->r_next;
	if (r->r_preference)
	new_r->r_preference = r->r_preference - 1;
	}
	}

	while ( (r = *rp) != NULL ) {
	if (r->r_preference > new_r->r_preference)
	break;
	rp = &r->r_next;
	}

	new_r->r_next = r;
	atomic_inc(&new_r->r_clntref);
	write_lock_bh(&fib_rules_lock);
	*rp = new_r;
	write_unlock_bh(&fib_rules_lock);
	return 0;
	}

	#ifdef CONFIG_NET_CLS_ROUTE
	u32 fib_rules_tclass(struct fib_result *res)
	{
	if (res->r)
	return res->r->r_tclassid;
	return 0;
	}
	#endif


	static void fib_rules_detach(struct net_device *dev)
	{
	struct fib_rule *r;

	for (r=fib_rules; r; r=r->r_next) {
	if (r->r_ifindex == dev->ifindex) {
	write_lock_bh(&fib_rules_lock);
	r->r_ifindex = -1;
	write_unlock_bh(&fib_rules_lock);
	}
	}
	}

	static void fib_rules_attach(struct net_device *dev)
	{
	struct fib_rule *r;

	for (r=fib_rules; r; r=r->r_next) {
	if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0) {
	write_lock_bh(&fib_rules_lock);
	r->r_ifindex = dev->ifindex;
	write_unlock_bh(&fib_rules_lock);
	}
	}
	}

	int fib_lookup(const struct flowi flp, struct fib_result res)
	{
	int err;
	struct fib_rule r, policy;
	struct fib_table *tb;

	u32 daddr = flp->fl4_dst;
	u32 saddr = flp->fl4_src;

	FRprintk("Lookup: %u.%u.%u.%u <- %u.%u.%u.%u ",
	NIPQUAD(flp->fl4_dst), NIPQUAD(flp->fl4_src));
	read_lock(&fib_rules_lock);
	for (r = fib_rules; r; r=r->r_next) {
	if (((saddr^r->r_src) & r->r_srcmask) \|\|
	((daddr^r->r_dst) & r->r_dstmask) \|\|
	(r->r_tos && r->r_tos != flp->fl4_tos) \|\|
	#ifdef CONFIG_IP_ROUTE_FWMARK
	(r->r_fwmark && r->r_fwmark != flp->fl4_fwmark) \|\|
	#endif
	(r->r_ifindex && r->r_ifindex != flp->iif))
	continue;

	FRprintk("tb %d r %d ", r->r_table, r->r_action);
	switch (r->r_action) {
	case RTN_UNICAST:
	policy = r;
	break;
	case RTN_UNREACHABLE:
	read_unlock(&fib_rules_lock);
	return -ENETUNREACH;
	default:
	case RTN_BLACKHOLE:
	read_unlock(&fib_rules_lock);
	return -EINVAL;
	case RTN_PROHIBIT:
	read_unlock(&fib_rules_lock);
	return -EACCES;
	}

	if ((tb = fib_get_table(r->r_table)) == NULL)
	continue;
	err = tb->tb_lookup(tb, flp, res);
	if (err == 0) {
	res->r = policy;
	if (policy)
	atomic_inc(&policy->r_clntref);
	read_unlock(&fib_rules_lock);
	return 0;
	}
	if (err < 0 && err != -EAGAIN) {
	read_unlock(&fib_rules_lock);
	return err;
	}
	}
	FRprintk("FAILURE\n");
	read_unlock(&fib_rules_lock);
	return -ENETUNREACH;
	}

	void fib_select_default(const struct flowi flp, struct fib_result res)
	{
	if (res->r && res->r->r_action == RTN_UNICAST &&
	FIB_RES_GW(res) && FIB_RES_NH(res).nh_scope == RT_SCOPE_LINK) {
	struct fib_table *tb;
	if ((tb = fib_get_table(res->r->r_table)) != NULL)
	tb->tb_select_default(tb, flp, res);
	}
	}

	static int fib_rules_event(struct notifier_block this, unsigned long event, void ptr)
	{
	struct net_device *dev = ptr;

	if (event == NETDEV_UNREGISTER)
	fib_rules_detach(dev);
	else if (event == NETDEV_REGISTER)
	fib_rules_attach(dev);
	return NOTIFY_DONE;
	}


	static struct notifier_block fib_rules_notifier = {
	.notifier_call =fib_rules_event,
	};

	static __inline__ int inet_fill_rule(struct sk_buff *skb,
	struct fib_rule *r,
	struct netlink_callback *cb,
	unsigned int flags)
	{
	struct rtmsg *rtm;
	struct nlmsghdr *nlh;
	unsigned char *b = skb->tail;

	nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWRULE, sizeof(*rtm), flags);
	rtm = NLMSG_DATA(nlh);
	rtm->rtm_family = AF_INET;
	rtm->rtm_dst_len = r->r_dst_len;
	rtm->rtm_src_len = r->r_src_len;
	rtm->rtm_tos = r->r_tos;
	#ifdef CONFIG_IP_ROUTE_FWMARK
	if (r->r_fwmark)
	RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);
	#endif
	rtm->rtm_table = r->r_table;
	rtm->rtm_protocol = 0;
	rtm->rtm_scope = 0;
	rtm->rtm_type = r->r_action;
	rtm->rtm_flags = r->r_flags;

	if (r->r_dst_len)
	RTA_PUT(skb, RTA_DST, 4, &r->r_dst);
	if (r->r_src_len)
	RTA_PUT(skb, RTA_SRC, 4, &r->r_src);
	if (r->r_ifname[0])
	RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);
	if (r->r_preference)
	RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);
	if (r->r_srcmap)
	RTA_PUT(skb, RTA_GATEWAY, 4, &r->r_srcmap);
	#ifdef CONFIG_NET_CLS_ROUTE
	if (r->r_tclassid)
	RTA_PUT(skb, RTA_FLOW, 4, &r->r_tclassid);
	#endif
	nlh->nlmsg_len = skb->tail - b;
	return skb->len;

	nlmsg_failure:
	rtattr_failure:
	skb_trim(skb, b - skb->data);
	return -1;
	}

	int inet_dump_rules(struct sk_buff skb, struct netlink_callback cb)
	{
	int idx;
	int s_idx = cb->args[0];
	struct fib_rule *r;

	read_lock(&fib_rules_lock);
	for (r=fib_rules, idx=0; r; r = r->r_next, idx++) {
	if (idx < s_idx)
	continue;
	if (inet_fill_rule(skb, r, cb, NLM_F_MULTI) < 0)
	break;
	}
	read_unlock(&fib_rules_lock);
	cb->args[0] = idx;

	return skb->len;
	}

	void __init fib_rules_init(void)
	{
	register_netdevice_notifier(&fib_rules_notifier);
	}