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