[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.
 *
 * Authors:	Alexey Kuznetsov, <[email protected]>
 *		Thomas Graf <[email protected]>
 *
 *		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/types.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <linux/inetdevice.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/rcupdate.h>
#include <linux/export.h>
#include <net/ip.h>
#include <net/route.h>
#include <net/tcp.h>
#include <net/ip_fib.h>
#include <net/fib_rules.h>

struct fib4_rule {
	struct fib_rule		common;
	u8			dst_len;
	u8			src_len;
	u8			tos;
	__be32			src;
	__be32			srcmask;
	__be32			dst;
	__be32			dstmask;
#ifdef CONFIG_IP_ROUTE_CLASSID
	u32			tclassid;
#endif
};

int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res)
{
	struct fib_lookup_arg arg = {
		.result = res,
		.flags = FIB_LOOKUP_NOREF,
	};
	int err;

	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
#ifdef CONFIG_IP_ROUTE_CLASSID
	if (arg.rule)
		res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
	else
		res->tclassid = 0;
#endif

	if (err == -ESRCH)
		err = -ENETUNREACH;

	return err;
}
EXPORT_SYMBOL_GPL(__fib_lookup);

static int fib4_rule_action(struct fib_rule *rule, struct flowi *flp,
			    int flags, struct fib_lookup_arg *arg)
{
	int err = -EAGAIN;
	struct fib_table *tbl;

	switch (rule->action) {
	case FR_ACT_TO_TBL:
		break;

	case FR_ACT_UNREACHABLE:
		return -ENETUNREACH;

	case FR_ACT_PROHIBIT:
		return -EACCES;

	case FR_ACT_BLACKHOLE:
	default:
		return -EINVAL;
	}

	rcu_read_lock();

	tbl = fib_get_table(rule->fr_net, rule->table);
	if (tbl)
		err = fib_table_lookup(tbl, &flp->u.ip4,
				       (struct fib_result *)arg->result,
				       arg->flags);

	rcu_read_unlock();
	return err;
}

static bool fib4_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
{
	struct fib_result *result = (struct fib_result *) arg->result;
	struct net_device *dev = NULL;

	if (result->fi)
		dev = result->fi->fib_dev;

	/* do not accept result if the route does
	 * not meet the required prefix length
	 */
	if (result->prefixlen <= rule->suppress_prefixlen)
		goto suppress_route;

	/* do not accept result if the route uses a device
	 * belonging to a forbidden interface group
	 */
	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
		goto suppress_route;

	return false;

suppress_route:
	if (!(arg->flags & FIB_LOOKUP_NOREF))
		fib_info_put(result->fi);
	return true;
}

static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
{
	struct fib4_rule *r = (struct fib4_rule *) rule;
	struct flowi4 *fl4 = &fl->u.ip4;
	__be32 daddr = fl4->daddr;
	__be32 saddr = fl4->saddr;

	if (((saddr ^ r->src) & r->srcmask) ||
	    ((daddr ^ r->dst) & r->dstmask))
		return 0;

	if (r->tos && (r->tos != fl4->flowi4_tos))
		return 0;

	return 1;
}

static struct fib_table *fib_empty_table(struct net *net)
{
	u32 id;

	for (id = 1; id <= RT_TABLE_MAX; id++)
		if (!fib_get_table(net, id))
			return fib_new_table(net, id);
	return NULL;
}

static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
	FRA_GENERIC_POLICY,
	[FRA_FLOW]	= { .type = NLA_U32 },
};

static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
			       struct fib_rule_hdr *frh,
			       struct nlattr **tb)
{
	struct net *net = sock_net(skb->sk);
	int err = -EINVAL;
	struct fib4_rule *rule4 = (struct fib4_rule *) rule;

	if (frh->tos & ~IPTOS_TOS_MASK)
		goto errout;

	/* split local/main if they are not already split */
	err = fib_unmerge(net);
	if (err)
		goto errout;

	if (rule->table == RT_TABLE_UNSPEC) {
		if (rule->action == FR_ACT_TO_TBL) {
			struct fib_table *table;

			table = fib_empty_table(net);
			if (!table) {
				err = -ENOBUFS;
				goto errout;
			}

			rule->table = table->tb_id;
		}
	}

	if (frh->src_len)
		rule4->src = nla_get_in_addr(tb[FRA_SRC]);

	if (frh->dst_len)
		rule4->dst = nla_get_in_addr(tb[FRA_DST]);

#ifdef CONFIG_IP_ROUTE_CLASSID
	if (tb[FRA_FLOW]) {
		rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
		if (rule4->tclassid)
			net->ipv4.fib_num_tclassid_users++;
	}
#endif

	rule4->src_len = frh->src_len;
	rule4->srcmask = inet_make_mask(rule4->src_len);
	rule4->dst_len = frh->dst_len;
	rule4->dstmask = inet_make_mask(rule4->dst_len);
	rule4->tos = frh->tos;

	net->ipv4.fib_has_custom_rules = true;
	fib_flush_external(rule->fr_net);

	err = 0;
errout:
	return err;
}

static int fib4_rule_delete(struct fib_rule *rule)
{
	struct net *net = rule->fr_net;
	int err;

	/* split local/main if they are not already split */
	err = fib_unmerge(net);
	if (err)
		goto errout;

#ifdef CONFIG_IP_ROUTE_CLASSID
	if (((struct fib4_rule *)rule)->tclassid)
		net->ipv4.fib_num_tclassid_users--;
#endif
	net->ipv4.fib_has_custom_rules = true;
	fib_flush_external(rule->fr_net);
errout:
	return err;
}

static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
			     struct nlattr **tb)
{
	struct fib4_rule *rule4 = (struct fib4_rule *) rule;

	if (frh->src_len && (rule4->src_len != frh->src_len))
		return 0;

	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
		return 0;

	if (frh->tos && (rule4->tos != frh->tos))
		return 0;

#ifdef CONFIG_IP_ROUTE_CLASSID
	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
		return 0;
#endif

	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
		return 0;

	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
		return 0;

	return 1;
}

static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
			  struct fib_rule_hdr *frh)
{
	struct fib4_rule *rule4 = (struct fib4_rule *) rule;

	frh->dst_len = rule4->dst_len;
	frh->src_len = rule4->src_len;
	frh->tos = rule4->tos;

	if ((rule4->dst_len &&
	     nla_put_in_addr(skb, FRA_DST, rule4->dst)) ||
	    (rule4->src_len &&
	     nla_put_in_addr(skb, FRA_SRC, rule4->src)))
		goto nla_put_failure;
#ifdef CONFIG_IP_ROUTE_CLASSID
	if (rule4->tclassid &&
	    nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
		goto nla_put_failure;
#endif
	return 0;

nla_put_failure:
	return -ENOBUFS;
}

static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
{
	return nla_total_size(4) /* dst */
	       + nla_total_size(4) /* src */
	       + nla_total_size(4); /* flow */
}

static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
{
	rt_cache_flush(ops->fro_net);
}

static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
	.family		= AF_INET,
	.rule_size	= sizeof(struct fib4_rule),
	.addr_size	= sizeof(u32),
	.action		= fib4_rule_action,
	.suppress	= fib4_rule_suppress,
	.match		= fib4_rule_match,
	.configure	= fib4_rule_configure,
	.delete		= fib4_rule_delete,
	.compare	= fib4_rule_compare,
	.fill		= fib4_rule_fill,
	.default_pref	= fib_default_rule_pref,
	.nlmsg_payload	= fib4_rule_nlmsg_payload,
	.flush_cache	= fib4_rule_flush_cache,
	.nlgroup	= RTNLGRP_IPV4_RULE,
	.policy		= fib4_rule_policy,
	.owner		= THIS_MODULE,
};

static int fib_default_rules_init(struct fib_rules_ops *ops)
{
	int err;

	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
	if (err < 0)
		return err;
	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
	if (err < 0)
		return err;
	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
	if (err < 0)
		return err;
	return 0;
}

int __net_init fib4_rules_init(struct net *net)
{
	int err;
	struct fib_rules_ops *ops;

	ops = fib_rules_register(&fib4_rules_ops_template, net);
	if (IS_ERR(ops))
		return PTR_ERR(ops);

	err = fib_default_rules_init(ops);
	if (err < 0)
		goto fail;
	net->ipv4.rules_ops = ops;
	net->ipv4.fib_has_custom_rules = false;
	return 0;

fail:
	/* also cleans all rules already added */
	fib_rules_unregister(ops);
	return err;
}

void __net_exit fib4_rules_exit(struct net *net)
{
	fib_rules_unregister(net->ipv4.rules_ops);
}
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	*
1da177e4	8	* Authors: Alexey Kuznetsov, <[email protected]>
6a31d2a9	9	* Thomas Graf <[email protected]>
1da177e4 LT	10	*
	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* as published by the Free Software Foundation; either version
	14	* 2 of the License, or (at your option) any later version.
	15	*
	16	* Fixes:
6a31d2a9	17	* Rani Assaf : local_rule cannot be deleted
1da177e4 LT	18	* Marc Boucher : routing by fwmark
	19	*/
	20
1da177e4 LT	21	#include <linux/types.h>
1da177e4 LT	22	#include <linux/kernel.h>
1da177e4	23	#include <linux/netdevice.h>
1da177e4	24	#include <linux/netlink.h>
e1ef4bf2	25	#include <linux/inetdevice.h>
1da177e4	26	#include <linux/init.h>
7b204afd RO	27	#include <linux/list.h>
7b204afd RO	28	#include <linux/rcupdate.h>
bc3b2d7f	29	#include <linux/export.h>
1da177e4	30	#include <net/ip.h>
1da177e4 LT	31	#include <net/route.h>
1da177e4 LT	32	#include <net/tcp.h>
1da177e4	33	#include <net/ip_fib.h>
e1ef4bf2	34	#include <net/fib_rules.h>
1da177e4	35
6a31d2a9	36	struct fib4_rule {
e1ef4bf2 TG	37	struct fib_rule common;
	38	u8 dst_len;
	39	u8 src_len;
	40	u8 tos;
81f7bf6c AV	41	__be32 src;
	42	__be32 srcmask;
	43	__be32 dst;
	44	__be32 dstmask;
c7066f70	45	#ifdef CONFIG_IP_ROUTE_CLASSID
e1ef4bf2	46	u32 tclassid;
1da177e4	47	#endif
1da177e4 LT	48	};
1da177e4 LT	49
f4530fa5	50	int __fib_lookup(struct net net, struct flowi4 flp, struct fib_result *res)
e1ef4bf2 TG	51	{
	52	struct fib_lookup_arg arg = {
	53	.result = res,
ebc0ffae	54	.flags = FIB_LOOKUP_NOREF,
e1ef4bf2 TG	55	};
e1ef4bf2 TG	56	int err;
1da177e4	57
22bd5b9b	58	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
85b91b03 DM	59	#ifdef CONFIG_IP_ROUTE_CLASSID
	60	if (arg.rule)
	61	res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
	62	else
	63	res->tclassid = 0;
	64	#endif
49dd18ba PM	65
	66	if (err == -ESRCH)
	67	err = -ENETUNREACH;
	68
e1ef4bf2 TG	69	return err;
e1ef4bf2 TG	70	}
f4530fa5	71	EXPORT_SYMBOL_GPL(__fib_lookup);
e1ef4bf2	72
8ce11e6a AB	73	static int fib4_rule_action(struct fib_rule rule, struct flowi flp,
8ce11e6a AB	74	int flags, struct fib_lookup_arg *arg)
1da177e4	75	{
e1ef4bf2 TG	76	int err = -EAGAIN;
	77	struct fib_table *tbl;
	78
	79	switch (rule->action) {
	80	case FR_ACT_TO_TBL:
	81	break;
	82
	83	case FR_ACT_UNREACHABLE:
345e9b54	84	return -ENETUNREACH;
e1ef4bf2 TG	85
e1ef4bf2 TG	86	case FR_ACT_PROHIBIT:
345e9b54	87	return -EACCES;
e1ef4bf2 TG	88
	89	case FR_ACT_BLACKHOLE:
	90	default:
345e9b54	91	return -EINVAL;
1da177e4	92	}
e1ef4bf2	93
345e9b54 AD	94	rcu_read_lock();
345e9b54 AD	95
6a31d2a9	96	tbl = fib_get_table(rule->fr_net, rule->table);
345e9b54 AD	97	if (tbl)
	98	err = fib_table_lookup(tbl, &flp->u.ip4,
	99	(struct fib_result *)arg->result,
	100	arg->flags);
e1ef4bf2	101
345e9b54	102	rcu_read_unlock();
1da177e4 LT	103	return err;
	104	}
	105
7764a45a ST	106	static bool fib4_rule_suppress(struct fib_rule rule, struct fib_lookup_arg arg)
7764a45a ST	107	{
6ef94cfa	108	struct fib_result result = (struct fib_result ) arg->result;
673498b8 ST	109	struct net_device *dev = NULL;
	110
	111	if (result->fi)
	112	dev = result->fi->fib_dev;
6ef94cfa	113
7764a45a ST	114	/* do not accept result if the route does
	115	* not meet the required prefix length
	116	*/
73f5698e	117	if (result->prefixlen <= rule->suppress_prefixlen)
6ef94cfa ST	118	goto suppress_route;
	119
	120	/* do not accept result if the route uses a device
	121	* belonging to a forbidden interface group
	122	*/
	123	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	124	goto suppress_route;
	125
7764a45a	126	return false;
6ef94cfa ST	127
	128	suppress_route:
	129	if (!(arg->flags & FIB_LOOKUP_NOREF))
	130	fib_info_put(result->fi);
	131	return true;
7764a45a	132	}
e1ef4bf2	133
e1ef4bf2 TG	134	static int fib4_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	135	{
	136	struct fib4_rule r = (struct fib4_rule ) rule;
9ade2286 DM	137	struct flowi4 *fl4 = &fl->u.ip4;
	138	__be32 daddr = fl4->daddr;
	139	__be32 saddr = fl4->saddr;
e1ef4bf2 TG	140
	141	if (((saddr ^ r->src) & r->srcmask) \|\|
	142	((daddr ^ r->dst) & r->dstmask))
	143	return 0;
	144
9ade2286	145	if (r->tos && (r->tos != fl4->flowi4_tos))
e1ef4bf2 TG	146	return 0;
e1ef4bf2 TG	147
e1ef4bf2 TG	148	return 1;
e1ef4bf2 TG	149	}
1da177e4	150
8ad4942c	151	static struct fib_table fib_empty_table(struct net net)
1da177e4	152	{
2dfe55b4	153	u32 id;
1da177e4 LT	154
1da177e4 LT	155	for (id = 1; id <= RT_TABLE_MAX; id++)
51456b29	156	if (!fib_get_table(net, id))
8ad4942c	157	return fib_new_table(net, id);
1da177e4 LT	158	return NULL;
	159	}
	160
ef7c79ed	161	static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
1f6c9557	162	FRA_GENERIC_POLICY,
e1ef4bf2 TG	163	[FRA_FLOW] = { .type = NLA_U32 },
e1ef4bf2 TG	164	};
7b204afd	165
e1ef4bf2	166	static int fib4_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	167	struct fib_rule_hdr *frh,
e1ef4bf2	168	struct nlattr **tb)
1da177e4	169	{
3b1e0a65	170	struct net *net = sock_net(skb->sk);
e1ef4bf2 TG	171	int err = -EINVAL;
e1ef4bf2 TG	172	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	173
e1701c68	174	if (frh->tos & ~IPTOS_TOS_MASK)
e1ef4bf2	175	goto errout;
7b204afd	176
0ddcf43d AD	177	/* split local/main if they are not already split */
	178	err = fib_unmerge(net);
	179	if (err)
	180	goto errout;
	181
e1ef4bf2 TG	182	if (rule->table == RT_TABLE_UNSPEC) {
	183	if (rule->action == FR_ACT_TO_TBL) {
	184	struct fib_table *table;
1da177e4	185
e4e4971c	186	table = fib_empty_table(net);
51456b29	187	if (!table) {
e1ef4bf2 TG	188	err = -ENOBUFS;
	189	goto errout;
	190	}
1da177e4	191
e1ef4bf2	192	rule->table = table->tb_id;
1da177e4 LT	193	}
	194	}
	195
e1701c68	196	if (frh->src_len)
67b61f6c	197	rule4->src = nla_get_in_addr(tb[FRA_SRC]);
7b204afd	198
e1701c68	199	if (frh->dst_len)
67b61f6c	200	rule4->dst = nla_get_in_addr(tb[FRA_DST]);
7b204afd	201
c7066f70	202	#ifdef CONFIG_IP_ROUTE_CLASSID
7a9bc9b8	203	if (tb[FRA_FLOW]) {
e1ef4bf2	204	rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
7a9bc9b8	205	if (rule4->tclassid)
f4530fa5	206	net->ipv4.fib_num_tclassid_users++;
7a9bc9b8	207	}
1da177e4 LT	208	#endif
1da177e4 LT	209
e1ef4bf2 TG	210	rule4->src_len = frh->src_len;
	211	rule4->srcmask = inet_make_mask(rule4->src_len);
	212	rule4->dst_len = frh->dst_len;
	213	rule4->dstmask = inet_make_mask(rule4->dst_len);
	214	rule4->tos = frh->tos;
7b204afd	215
f4530fa5	216	net->ipv4.fib_has_custom_rules = true;
104616e7 SF	217	fib_flush_external(rule->fr_net);
104616e7 SF	218
e1ef4bf2 TG	219	err = 0;
	220	errout:
	221	return err;
1da177e4 LT	222	}
1da177e4 LT	223
0ddcf43d	224	static int fib4_rule_delete(struct fib_rule *rule)
7a9bc9b8	225	{
f4530fa5	226	struct net *net = rule->fr_net;
0ddcf43d	227	int err;
7a9bc9b8	228
0ddcf43d AD	229	/* split local/main if they are not already split */
	230	err = fib_unmerge(net);
	231	if (err)
	232	goto errout;
	233
	234	#ifdef CONFIG_IP_ROUTE_CLASSID
	235	if (((struct fib4_rule *)rule)->tclassid)
f4530fa5	236	net->ipv4.fib_num_tclassid_users--;
7a9bc9b8	237	#endif
f4530fa5	238	net->ipv4.fib_has_custom_rules = true;
104616e7	239	fib_flush_external(rule->fr_net);
0ddcf43d AD	240	errout:
0ddcf43d AD	241	return err;
7a9bc9b8 DM	242	}
7a9bc9b8 DM	243
e1ef4bf2 TG	244	static int fib4_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
e1ef4bf2 TG	245	struct nlattr **tb)
1da177e4	246	{
e1ef4bf2	247	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	248
e1ef4bf2 TG	249	if (frh->src_len && (rule4->src_len != frh->src_len))
e1ef4bf2 TG	250	return 0;
1da177e4	251
e1ef4bf2 TG	252	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
e1ef4bf2 TG	253	return 0;
7b204afd	254
e1ef4bf2 TG	255	if (frh->tos && (rule4->tos != frh->tos))
e1ef4bf2 TG	256	return 0;
7b204afd	257
c7066f70	258	#ifdef CONFIG_IP_ROUTE_CLASSID
e1ef4bf2 TG	259	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
	260	return 0;
	261	#endif
1da177e4	262
67b61f6c	263	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
e1ef4bf2	264	return 0;
1da177e4	265
67b61f6c	266	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
e1ef4bf2	267	return 0;
1da177e4	268
e1ef4bf2	269	return 1;
1da177e4 LT	270	}
1da177e4 LT	271
e1ef4bf2	272	static int fib4_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	273	struct fib_rule_hdr *frh)
e1ef4bf2 TG	274	{
e1ef4bf2 TG	275	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	276
e1ef4bf2 TG	277	frh->dst_len = rule4->dst_len;
	278	frh->src_len = rule4->src_len;
	279	frh->tos = rule4->tos;
1da177e4	280
f3756b79	281	if ((rule4->dst_len &&
930345ea	282	nla_put_in_addr(skb, FRA_DST, rule4->dst)) \|\|
f3756b79	283	(rule4->src_len &&
930345ea	284	nla_put_in_addr(skb, FRA_SRC, rule4->src)))
f3756b79	285	goto nla_put_failure;
c7066f70	286	#ifdef CONFIG_IP_ROUTE_CLASSID
f3756b79 DM	287	if (rule4->tclassid &&
	288	nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
	289	goto nla_put_failure;
1da177e4	290	#endif
e1ef4bf2	291	return 0;
1da177e4	292
e1ef4bf2 TG	293	nla_put_failure:
e1ef4bf2 TG	294	return -ENOBUFS;
1da177e4 LT	295	}
1da177e4 LT	296
339bf98f TG	297	static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
	298	{
	299	return nla_total_size(4) /* dst */
	300	+ nla_total_size(4) /* src */
	301	+ nla_total_size(4); /* flow */
	302	}
	303
ae299fc0	304	static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
73417f61	305	{
bafa6d9d	306	rt_cache_flush(ops->fro_net);
73417f61 TG	307	}
73417f61 TG	308
04a6f82c	309	static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
25239cee	310	.family = AF_INET,
e1ef4bf2	311	.rule_size = sizeof(struct fib4_rule),
e1701c68	312	.addr_size = sizeof(u32),
e1ef4bf2	313	.action = fib4_rule_action,
7764a45a	314	.suppress = fib4_rule_suppress,
e1ef4bf2 TG	315	.match = fib4_rule_match,
e1ef4bf2 TG	316	.configure = fib4_rule_configure,
7a9bc9b8	317	.delete = fib4_rule_delete,
e1ef4bf2 TG	318	.compare = fib4_rule_compare,
e1ef4bf2 TG	319	.fill = fib4_rule_fill,
d8a566be	320	.default_pref = fib_default_rule_pref,
339bf98f	321	.nlmsg_payload = fib4_rule_nlmsg_payload,
73417f61	322	.flush_cache = fib4_rule_flush_cache,
e1ef4bf2 TG	323	.nlgroup = RTNLGRP_IPV4_RULE,
e1ef4bf2 TG	324	.policy = fib4_rule_policy,
e1ef4bf2 TG	325	.owner = THIS_MODULE,
	326	};
	327
e4e4971c	328	static int fib_default_rules_init(struct fib_rules_ops *ops)
1da177e4	329	{
2994c638 DL	330	int err;
2994c638 DL	331
5adef180	332	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
2994c638 DL	333	if (err < 0)
2994c638 DL	334	return err;
e4e4971c	335	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
2994c638 DL	336	if (err < 0)
2994c638 DL	337	return err;
e4e4971c	338	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
2994c638 DL	339	if (err < 0)
	340	return err;
	341	return 0;
	342	}
1da177e4	343
7b1a74fd	344	int __net_init fib4_rules_init(struct net *net)
2994c638	345	{
dbb50165	346	int err;
e4e4971c DL	347	struct fib_rules_ops *ops;
e4e4971c DL	348
e9c5158a EB	349	ops = fib_rules_register(&fib4_rules_ops_template, net);
	350	if (IS_ERR(ops))
	351	return PTR_ERR(ops);
dbb50165	352
e4e4971c	353	err = fib_default_rules_init(ops);
dbb50165 DL	354	if (err < 0)
dbb50165 DL	355	goto fail;
e4e4971c	356	net->ipv4.rules_ops = ops;
f4530fa5	357	net->ipv4.fib_has_custom_rules = false;
dbb50165 DL	358	return 0;
	359
	360	fail:
	361	/* also cleans all rules already added */
9e3a5487	362	fib_rules_unregister(ops);
dbb50165	363	return err;
1da177e4	364	}
7b1a74fd DL	365
	366	void __net_exit fib4_rules_exit(struct net *net)
	367	{
9e3a5487	368	fib_rules_unregister(net->ipv4.rules_ops);
7b1a74fd	369	}