[net-next-2.6.git] / net / ipv4 / fib_rules.c

/*
 * 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/inetdevice.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);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* INET An implementation of the TCP/IP protocol suite for the LINUX
	3	* operating system. INET is implemented using the BSD Socket
	4	* interface as the means of communication with the user level.
	5	*
	6	* IPv4 Forwarding Information Base: policy rules.
	7	*
	8	* Version: $Id: fib_rules.c,v 1.17 2001/10/31 21:55:54 davem Exp $
	9	*
	10	* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
	11	*
	12	* This program is free software; you can redistribute it and/or
	13	* modify it under the terms of the GNU General Public License
	14	* as published by the Free Software Foundation; either version
	15	* 2 of the License, or (at your option) any later version.
	16	*
	17	* Fixes:
	18	* Rani Assaf : local_rule cannot be deleted
	19	* Marc Boucher : routing by fwmark
	20	*/
	21
	22	#include <linux/config.h>
	23	#include <asm/uaccess.h>
	24	#include <asm/system.h>
	25	#include <linux/bitops.h>
	26	#include <linux/types.h>
	27	#include <linux/kernel.h>
	28	#include <linux/sched.h>
	29	#include <linux/mm.h>
	30	#include <linux/string.h>
	31	#include <linux/socket.h>
	32	#include <linux/sockios.h>
	33	#include <linux/errno.h>
	34	#include <linux/in.h>
	35	#include <linux/inet.h>
14c85021	36	#include <linux/inetdevice.h>
1da177e4 LT	37	#include <linux/netdevice.h>
	38	#include <linux/if_arp.h>
	39	#include <linux/proc_fs.h>
	40	#include <linux/skbuff.h>
	41	#include <linux/netlink.h>
	42	#include <linux/init.h>
	43
	44	#include <net/ip.h>
	45	#include <net/protocol.h>
	46	#include <net/route.h>
	47	#include <net/tcp.h>
	48	#include <net/sock.h>
	49	#include <net/ip_fib.h>
	50
	51	#define FRprintk(a...)
	52
	53	struct fib_rule
	54	{
	55	struct fib_rule *r_next;
	56	atomic_t r_clntref;
	57	u32 r_preference;
	58	unsigned char r_table;
	59	unsigned char r_action;
	60	unsigned char r_dst_len;
	61	unsigned char r_src_len;
	62	u32 r_src;
	63	u32 r_srcmask;
	64	u32 r_dst;
	65	u32 r_dstmask;
	66	u32 r_srcmap;
	67	u8 r_flags;
	68	u8 r_tos;
	69	#ifdef CONFIG_IP_ROUTE_FWMARK
	70	u32 r_fwmark;
	71	#endif
	72	int r_ifindex;
	73	#ifdef CONFIG_NET_CLS_ROUTE
	74	__u32 r_tclassid;
	75	#endif
	76	char r_ifname[IFNAMSIZ];
	77	int r_dead;
	78	};
	79
	80	static struct fib_rule default_rule = {
	81	.r_clntref = ATOMIC_INIT(2),
	82	.r_preference = 0x7FFF,
	83	.r_table = RT_TABLE_DEFAULT,
	84	.r_action = RTN_UNICAST,
	85	};
	86
	87	static struct fib_rule main_rule = {
	88	.r_next = &default_rule,
	89	.r_clntref = ATOMIC_INIT(2),
	90	.r_preference = 0x7FFE,
	91	.r_table = RT_TABLE_MAIN,
	92	.r_action = RTN_UNICAST,
	93	};
	94
	95	static struct fib_rule local_rule = {
	96	.r_next = &main_rule,
	97	.r_clntref = ATOMIC_INIT(2),
	98	.r_table = RT_TABLE_LOCAL,
	99	.r_action = RTN_UNICAST,
	100	};
101
102	static struct fib_rule *fib_rules = &local_rule;
103	static DEFINE_RWLOCK(fib_rules_lock);
104
105	int inet_rtm_delrule(struct sk_buff skb, struct nlmsghdr nlh, void *arg)
106	{
107	struct rtattr **rta = arg;
108	struct rtmsg *rtm = NLMSG_DATA(nlh);
109	struct fib_rule r, *rp;
110	int err = -ESRCH;
111
112	for (rp=&fib_rules; (r=*rp) != NULL; rp=&r->r_next) {
113	if ((!rta[RTA_SRC-1] \|\| memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 4) == 0) &&
114	rtm->rtm_src_len == r->r_src_len &&
115	rtm->rtm_dst_len == r->r_dst_len &&
116	(!rta[RTA_DST-1] \|\| memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 4) == 0) &&
117	rtm->rtm_tos == r->r_tos &&
118	#ifdef CONFIG_IP_ROUTE_FWMARK
119	(!rta[RTA_PROTOINFO-1] \|\| memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&
120	#endif
121	(!rtm->rtm_type \|\| rtm->rtm_type == r->r_action) &&
122	(!rta[RTA_PRIORITY-1] \|\| memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&
123	(!rta[RTA_IIF-1] \|\| rtattr_strcmp(rta[RTA_IIF-1], r->r_ifname) == 0) &&
124	(!rtm->rtm_table \|\| (r && rtm->rtm_table == r->r_table))) {
125	err = -EPERM;
126	if (r == &local_rule)
127	break;
128
129	write_lock_bh(&fib_rules_lock);
130	*rp = r->r_next;
131	r->r_dead = 1;
132	write_unlock_bh(&fib_rules_lock);
133	fib_rule_put(r);
134	err = 0;
135	break;
136	}
137	}
138	return err;
139	}
140
141	/* Allocate new unique table id */
142
143	static struct fib_table *fib_empty_table(void)
144	{
145	int id;
146
147	for (id = 1; id <= RT_TABLE_MAX; id++)
148	if (fib_tables[id] == NULL)
149	return __fib_new_table(id);
150	return NULL;
151	}
152
153	void fib_rule_put(struct fib_rule *r)
154	{
155	if (atomic_dec_and_test(&r->r_clntref)) {
156	if (r->r_dead)
157	kfree(r);
158	else
159	printk("Freeing alive rule %p\n", r);
160	}
161	}
162
163	int inet_rtm_newrule(struct sk_buff skb, struct nlmsghdr nlh, void *arg)
164	{
165	struct rtattr **rta = arg;
166	struct rtmsg *rtm = NLMSG_DATA(nlh);
167	struct fib_rule r, new_r, **rp;
168	unsigned char table_id;
169
170	if (rtm->rtm_src_len > 32 \|\| rtm->rtm_dst_len > 32 \|\|
171	(rtm->rtm_tos & ~IPTOS_TOS_MASK))
172	return -EINVAL;
173
174	if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)
175	return -EINVAL;
176
177	table_id = rtm->rtm_table;
178	if (table_id == RT_TABLE_UNSPEC) {
179	struct fib_table *table;
180	if (rtm->rtm_type == RTN_UNICAST) {
181	if ((table = fib_empty_table()) == NULL)
182	return -ENOBUFS;
183	table_id = table->tb_id;
184	}
185	}
186
187	new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);
188	if (!new_r)
189	return -ENOMEM;
190	memset(new_r, 0, sizeof(*new_r));
191	if (rta[RTA_SRC-1])
192	memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 4);
193	if (rta[RTA_DST-1])
194	memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 4);
195	if (rta[RTA_GATEWAY-1])
196	memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 4);
197	new_r->r_src_len = rtm->rtm_src_len;
198	new_r->r_dst_len = rtm->rtm_dst_len;
199	new_r->r_srcmask = inet_make_mask(rtm->rtm_src_len);
200	new_r->r_dstmask = inet_make_mask(rtm->rtm_dst_len);
201	new_r->r_tos = rtm->rtm_tos;
202	#ifdef CONFIG_IP_ROUTE_FWMARK
203	if (rta[RTA_PROTOINFO-1])
204	memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);
205	#endif
206	new_r->r_action = rtm->rtm_type;
207	new_r->r_flags = rtm->rtm_flags;
208	if (rta[RTA_PRIORITY-1])
209	memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);
210	new_r->r_table = table_id;
211	if (rta[RTA_IIF-1]) {
212	struct net_device *dev;
213	rtattr_strlcpy(new_r->r_ifname, rta[RTA_IIF-1], IFNAMSIZ);
214	new_r->r_ifindex = -1;
215	dev = __dev_get_by_name(new_r->r_ifname);
216	if (dev)
217	new_r->r_ifindex = dev->ifindex;
218	}
219	#ifdef CONFIG_NET_CLS_ROUTE
220	if (rta[RTA_FLOW-1])
221	memcpy(&new_r->r_tclassid, RTA_DATA(rta[RTA_FLOW-1]), 4);
222	#endif
223
224	rp = &fib_rules;
225	if (!new_r->r_preference) {
226	r = fib_rules;
227	if (r && (r = r->r_next) != NULL) {
228	rp = &fib_rules->r_next;
229	if (r->r_preference)
230	new_r->r_preference = r->r_preference - 1;
231	}
232	}
233
234	while ( (r = *rp) != NULL ) {
235	if (r->r_preference > new_r->r_preference)
236	break;
237	rp = &r->r_next;
238	}
239
240	new_r->r_next = r;
241	atomic_inc(&new_r->r_clntref);
242	write_lock_bh(&fib_rules_lock);
243	*rp = new_r;
244	write_unlock_bh(&fib_rules_lock);
245	return 0;
246	}
247
248	#ifdef CONFIG_NET_CLS_ROUTE
249	u32 fib_rules_tclass(struct fib_result *res)
250	{
251	if (res->r)
252	return res->r->r_tclassid;
253	return 0;
254	}
255	#endif
256
257
258	static void fib_rules_detach(struct net_device *dev)
259	{
260	struct fib_rule *r;
261
262	for (r=fib_rules; r; r=r->r_next) {
263	if (r->r_ifindex == dev->ifindex) {
264	write_lock_bh(&fib_rules_lock);
265	r->r_ifindex = -1;
266	write_unlock_bh(&fib_rules_lock);
267	}
268	}
269	}
270
271	static void fib_rules_attach(struct net_device *dev)
272	{
273	struct fib_rule *r;
274
275	for (r=fib_rules; r; r=r->r_next) {
276	if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0) {
277	write_lock_bh(&fib_rules_lock);
278	r->r_ifindex = dev->ifindex;
279	write_unlock_bh(&fib_rules_lock);
280	}
281	}
282	}
283
284	int fib_lookup(const struct flowi flp, struct fib_result res)
285	{
286	int err;
287	struct fib_rule r, policy;
288	struct fib_table *tb;
289
290	u32 daddr = flp->fl4_dst;
291	u32 saddr = flp->fl4_src;
292
293	FRprintk("Lookup: %u.%u.%u.%u <- %u.%u.%u.%u ",
294	NIPQUAD(flp->fl4_dst), NIPQUAD(flp->fl4_src));
295	read_lock(&fib_rules_lock);
296	for (r = fib_rules; r; r=r->r_next) {
297	if (((saddr^r->r_src) & r->r_srcmask) \|\|
298	((daddr^r->r_dst) & r->r_dstmask) \|\|
299	(r->r_tos && r->r_tos != flp->fl4_tos) \|\|
300	#ifdef CONFIG_IP_ROUTE_FWMARK
301	(r->r_fwmark && r->r_fwmark != flp->fl4_fwmark) \|\|
302	#endif
303	(r->r_ifindex && r->r_ifindex != flp->iif))
304	continue;
305
306	FRprintk("tb %d r %d ", r->r_table, r->r_action);
307	switch (r->r_action) {
308	case RTN_UNICAST:
309	policy = r;
310	break;
311	case RTN_UNREACHABLE:
312	read_unlock(&fib_rules_lock);
313	return -ENETUNREACH;
314	default:
315	case RTN_BLACKHOLE:
316	read_unlock(&fib_rules_lock);
317	return -EINVAL;
318	case RTN_PROHIBIT:
319	read_unlock(&fib_rules_lock);
320	return -EACCES;
321	}
322
323	if ((tb = fib_get_table(r->r_table)) == NULL)
324	continue;
325	err = tb->tb_lookup(tb, flp, res);
326	if (err == 0) {
327	res->r = policy;
328	if (policy)
329	atomic_inc(&policy->r_clntref);
330	read_unlock(&fib_rules_lock);
331	return 0;
332	}
333	if (err < 0 && err != -EAGAIN) {
334	read_unlock(&fib_rules_lock);
335	return err;
336	}
337	}
338	FRprintk("FAILURE\n");
339	read_unlock(&fib_rules_lock);
340	return -ENETUNREACH;
341	}
342
343	void fib_select_default(const struct flowi flp, struct fib_result res)
344	{
345	if (res->r && res->r->r_action == RTN_UNICAST &&
346	FIB_RES_GW(res) && FIB_RES_NH(res).nh_scope == RT_SCOPE_LINK) {
347	struct fib_table *tb;
348	if ((tb = fib_get_table(res->r->r_table)) != NULL)
349	tb->tb_select_default(tb, flp, res);
350	}
351	}
352
353	static int fib_rules_event(struct notifier_block this, unsigned long event, void ptr)
354	{
355	struct net_device *dev = ptr;
356
357	if (event == NETDEV_UNREGISTER)
358	fib_rules_detach(dev);
359	else if (event == NETDEV_REGISTER)
360	fib_rules_attach(dev);
361	return NOTIFY_DONE;
362	}
363
364
365	static struct notifier_block fib_rules_notifier = {
366	.notifier_call =fib_rules_event,
367	};
368
369	static __inline__ int inet_fill_rule(struct sk_buff *skb,
370	struct fib_rule *r,
b6544c0b JHS	371	struct netlink_callback *cb,
b6544c0b JHS	372	unsigned int flags)
1da177e4 LT	373	{
	374	struct rtmsg *rtm;
	375	struct nlmsghdr *nlh;
	376	unsigned char *b = skb->tail;
	377
b6544c0b	378	nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWRULE, sizeof(*rtm), flags);
1da177e4 LT	379	rtm = NLMSG_DATA(nlh);
	380	rtm->rtm_family = AF_INET;
	381	rtm->rtm_dst_len = r->r_dst_len;
	382	rtm->rtm_src_len = r->r_src_len;
	383	rtm->rtm_tos = r->r_tos;
	384	#ifdef CONFIG_IP_ROUTE_FWMARK
	385	if (r->r_fwmark)
	386	RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);
	387	#endif
	388	rtm->rtm_table = r->r_table;
	389	rtm->rtm_protocol = 0;
	390	rtm->rtm_scope = 0;
	391	rtm->rtm_type = r->r_action;
	392	rtm->rtm_flags = r->r_flags;
	393
	394	if (r->r_dst_len)
	395	RTA_PUT(skb, RTA_DST, 4, &r->r_dst);
	396	if (r->r_src_len)
	397	RTA_PUT(skb, RTA_SRC, 4, &r->r_src);
	398	if (r->r_ifname[0])
	399	RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);
	400	if (r->r_preference)
	401	RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);
	402	if (r->r_srcmap)
	403	RTA_PUT(skb, RTA_GATEWAY, 4, &r->r_srcmap);
	404	#ifdef CONFIG_NET_CLS_ROUTE
	405	if (r->r_tclassid)
	406	RTA_PUT(skb, RTA_FLOW, 4, &r->r_tclassid);
	407	#endif
	408	nlh->nlmsg_len = skb->tail - b;
	409	return skb->len;
	410
	411	nlmsg_failure:
	412	rtattr_failure:
	413	skb_trim(skb, b - skb->data);
	414	return -1;
	415	}
	416
	417	int inet_dump_rules(struct sk_buff skb, struct netlink_callback cb)
	418	{
	419	int idx;
	420	int s_idx = cb->args[0];
	421	struct fib_rule *r;
	422
	423	read_lock(&fib_rules_lock);
	424	for (r=fib_rules, idx=0; r; r = r->r_next, idx++) {
	425	if (idx < s_idx)
	426	continue;
b6544c0b	427	if (inet_fill_rule(skb, r, cb, NLM_F_MULTI) < 0)
1da177e4 LT	428	break;
	429	}
	430	read_unlock(&fib_rules_lock);
	431	cb->args[0] = idx;
	432
	433	return skb->len;
	434	}
	435
	436	void __init fib_rules_init(void)
	437	{
	438	register_netdevice_notifier(&fib_rules_notifier);
	439	}