[linux-2.6-block.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, <kuznet@ms2.inr.ac.ru>
 *		Thomas Graf <tgraf@suug.ch>
 *
 *		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
};

static bool fib4_rule_matchall(const struct fib_rule *rule)
{
	struct fib4_rule *r = container_of(rule, struct fib4_rule, common);

	if (r->dst_len || r->src_len || r->tos)
		return false;
	return fib_rule_matchall(rule);
}

bool fib4_rule_default(const struct fib_rule *rule)
{
	if (!fib4_rule_matchall(rule) || rule->action != FR_ACT_TO_TBL ||
	    rule->l3mdev)
		return false;
	if (rule->table != RT_TABLE_LOCAL && rule->table != RT_TABLE_MAIN &&
	    rule->table != RT_TABLE_DEFAULT)
		return false;
	return true;
}
EXPORT_SYMBOL_GPL(fib4_rule_default);

int fib4_rules_dump(struct net *net, struct notifier_block *nb)
{
	return fib_rules_dump(net, nb, AF_INET);
}

unsigned int fib4_rules_seq_read(struct net *net)
{
	return fib_rules_seq_read(net, AF_INET);
}

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

	/* update flow if oif or iif point to device enslaved to l3mdev */
	l3mdev_update_flow(net, flowi4_to_flowi(flp));

	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;
	u32 tb_id;

	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();

	tb_id = fib_rule_get_table(rule, arg);
	tbl = fib_get_table(rule->fr_net, tb_id);
	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 && !rule->l3mdev) {
		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;

	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;
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,
	.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, <kuznet@ms2.inr.ac.ru>
6a31d2a9	9	* Thomas Graf <tgraf@suug.ch>
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
3c71006d IS	50	static bool fib4_rule_matchall(const struct fib_rule *rule)
	51	{
	52	struct fib4_rule *r = container_of(rule, struct fib4_rule, common);
	53
	54	if (r->dst_len \|\| r->src_len \|\| r->tos)
	55	return false;
	56	return fib_rule_matchall(rule);
	57	}
	58
	59	bool fib4_rule_default(const struct fib_rule *rule)
	60	{
	61	if (!fib4_rule_matchall(rule) \|\| rule->action != FR_ACT_TO_TBL \|\|
	62	rule->l3mdev)
	63	return false;
	64	if (rule->table != RT_TABLE_LOCAL && rule->table != RT_TABLE_MAIN &&
	65	rule->table != RT_TABLE_DEFAULT)
	66	return false;
	67	return true;
	68	}
	69	EXPORT_SYMBOL_GPL(fib4_rule_default);
	70
1b2a4440 IS	71	int fib4_rules_dump(struct net net, struct notifier_block nb)
	72	{
	73	return fib_rules_dump(net, nb, AF_INET);
	74	}
	75
	76	unsigned int fib4_rules_seq_read(struct net *net)
	77	{
	78	return fib_rules_seq_read(net, AF_INET);
	79	}
	80
0eeb075f AG	81	int __fib_lookup(struct net net, struct flowi4 flp,
0eeb075f AG	82	struct fib_result *res, unsigned int flags)
e1ef4bf2 TG	83	{
	84	struct fib_lookup_arg arg = {
	85	.result = res,
0eeb075f	86	.flags = flags,
e1ef4bf2 TG	87	};
e1ef4bf2 TG	88	int err;
1da177e4	89
9ee0034b DA	90	/* update flow if oif or iif point to device enslaved to l3mdev */
	91	l3mdev_update_flow(net, flowi4_to_flowi(flp));
	92
22bd5b9b	93	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
85b91b03 DM	94	#ifdef CONFIG_IP_ROUTE_CLASSID
	95	if (arg.rule)
	96	res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
	97	else
	98	res->tclassid = 0;
	99	#endif
49dd18ba PM	100
	101	if (err == -ESRCH)
	102	err = -ENETUNREACH;
	103
e1ef4bf2 TG	104	return err;
e1ef4bf2 TG	105	}
f4530fa5	106	EXPORT_SYMBOL_GPL(__fib_lookup);
e1ef4bf2	107
8ce11e6a AB	108	static int fib4_rule_action(struct fib_rule rule, struct flowi flp,
8ce11e6a AB	109	int flags, struct fib_lookup_arg *arg)
1da177e4	110	{
e1ef4bf2 TG	111	int err = -EAGAIN;
e1ef4bf2 TG	112	struct fib_table *tbl;
96c63fa7	113	u32 tb_id;
e1ef4bf2 TG	114
	115	switch (rule->action) {
	116	case FR_ACT_TO_TBL:
	117	break;
	118
	119	case FR_ACT_UNREACHABLE:
345e9b54	120	return -ENETUNREACH;
e1ef4bf2 TG	121
e1ef4bf2 TG	122	case FR_ACT_PROHIBIT:
345e9b54	123	return -EACCES;
e1ef4bf2 TG	124
	125	case FR_ACT_BLACKHOLE:
	126	default:
345e9b54	127	return -EINVAL;
1da177e4	128	}
e1ef4bf2	129
345e9b54 AD	130	rcu_read_lock();
345e9b54 AD	131
96c63fa7 DA	132	tb_id = fib_rule_get_table(rule, arg);
96c63fa7 DA	133	tbl = fib_get_table(rule->fr_net, tb_id);
345e9b54 AD	134	if (tbl)
	135	err = fib_table_lookup(tbl, &flp->u.ip4,
	136	(struct fib_result *)arg->result,
	137	arg->flags);
e1ef4bf2	138
345e9b54	139	rcu_read_unlock();
1da177e4 LT	140	return err;
	141	}
	142
7764a45a ST	143	static bool fib4_rule_suppress(struct fib_rule rule, struct fib_lookup_arg arg)
7764a45a ST	144	{
6ef94cfa	145	struct fib_result result = (struct fib_result ) arg->result;
673498b8 ST	146	struct net_device *dev = NULL;
	147
	148	if (result->fi)
	149	dev = result->fi->fib_dev;
6ef94cfa	150
7764a45a ST	151	/* do not accept result if the route does
	152	* not meet the required prefix length
	153	*/
73f5698e	154	if (result->prefixlen <= rule->suppress_prefixlen)
6ef94cfa ST	155	goto suppress_route;
	156
	157	/* do not accept result if the route uses a device
	158	* belonging to a forbidden interface group
	159	*/
	160	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	161	goto suppress_route;
	162
7764a45a	163	return false;
6ef94cfa ST	164
	165	suppress_route:
	166	if (!(arg->flags & FIB_LOOKUP_NOREF))
	167	fib_info_put(result->fi);
	168	return true;
7764a45a	169	}
e1ef4bf2	170
e1ef4bf2 TG	171	static int fib4_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	172	{
	173	struct fib4_rule r = (struct fib4_rule ) rule;
9ade2286 DM	174	struct flowi4 *fl4 = &fl->u.ip4;
	175	__be32 daddr = fl4->daddr;
	176	__be32 saddr = fl4->saddr;
e1ef4bf2 TG	177
	178	if (((saddr ^ r->src) & r->srcmask) \|\|
	179	((daddr ^ r->dst) & r->dstmask))
	180	return 0;
	181
9ade2286	182	if (r->tos && (r->tos != fl4->flowi4_tos))
e1ef4bf2 TG	183	return 0;
e1ef4bf2 TG	184
e1ef4bf2 TG	185	return 1;
e1ef4bf2 TG	186	}
1da177e4	187
8ad4942c	188	static struct fib_table fib_empty_table(struct net net)
1da177e4	189	{
2dfe55b4	190	u32 id;
1da177e4 LT	191
1da177e4 LT	192	for (id = 1; id <= RT_TABLE_MAX; id++)
51456b29	193	if (!fib_get_table(net, id))
8ad4942c	194	return fib_new_table(net, id);
1da177e4 LT	195	return NULL;
	196	}
	197
ef7c79ed	198	static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
1f6c9557	199	FRA_GENERIC_POLICY,
e1ef4bf2 TG	200	[FRA_FLOW] = { .type = NLA_U32 },
e1ef4bf2 TG	201	};
7b204afd	202
e1ef4bf2	203	static int fib4_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	204	struct fib_rule_hdr *frh,
e1ef4bf2	205	struct nlattr **tb)
1da177e4	206	{
3b1e0a65	207	struct net *net = sock_net(skb->sk);
e1ef4bf2 TG	208	int err = -EINVAL;
e1ef4bf2 TG	209	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	210
e1701c68	211	if (frh->tos & ~IPTOS_TOS_MASK)
e1ef4bf2	212	goto errout;
7b204afd	213
0ddcf43d AD	214	/* split local/main if they are not already split */
	215	err = fib_unmerge(net);
	216	if (err)
	217	goto errout;
	218
96c63fa7	219	if (rule->table == RT_TABLE_UNSPEC && !rule->l3mdev) {
e1ef4bf2 TG	220	if (rule->action == FR_ACT_TO_TBL) {
e1ef4bf2 TG	221	struct fib_table *table;
1da177e4	222
e4e4971c	223	table = fib_empty_table(net);
51456b29	224	if (!table) {
e1ef4bf2 TG	225	err = -ENOBUFS;
	226	goto errout;
	227	}
1da177e4	228
e1ef4bf2	229	rule->table = table->tb_id;
1da177e4 LT	230	}
	231	}
	232
e1701c68	233	if (frh->src_len)
67b61f6c	234	rule4->src = nla_get_in_addr(tb[FRA_SRC]);
7b204afd	235
e1701c68	236	if (frh->dst_len)
67b61f6c	237	rule4->dst = nla_get_in_addr(tb[FRA_DST]);
7b204afd	238
c7066f70	239	#ifdef CONFIG_IP_ROUTE_CLASSID
7a9bc9b8	240	if (tb[FRA_FLOW]) {
e1ef4bf2	241	rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
7a9bc9b8	242	if (rule4->tclassid)
f4530fa5	243	net->ipv4.fib_num_tclassid_users++;
7a9bc9b8	244	}
1da177e4 LT	245	#endif
1da177e4 LT	246
e1ef4bf2 TG	247	rule4->src_len = frh->src_len;
	248	rule4->srcmask = inet_make_mask(rule4->src_len);
	249	rule4->dst_len = frh->dst_len;
	250	rule4->dstmask = inet_make_mask(rule4->dst_len);
	251	rule4->tos = frh->tos;
7b204afd	252
f4530fa5	253	net->ipv4.fib_has_custom_rules = true;
104616e7	254
e1ef4bf2 TG	255	err = 0;
	256	errout:
	257	return err;
1da177e4 LT	258	}
1da177e4 LT	259
0ddcf43d	260	static int fib4_rule_delete(struct fib_rule *rule)
7a9bc9b8	261	{
f4530fa5	262	struct net *net = rule->fr_net;
0ddcf43d	263	int err;
7a9bc9b8	264
0ddcf43d AD	265	/* split local/main if they are not already split */
	266	err = fib_unmerge(net);
	267	if (err)
	268	goto errout;
	269
	270	#ifdef CONFIG_IP_ROUTE_CLASSID
	271	if (((struct fib4_rule *)rule)->tclassid)
f4530fa5	272	net->ipv4.fib_num_tclassid_users--;
7a9bc9b8	273	#endif
f4530fa5	274	net->ipv4.fib_has_custom_rules = true;
0ddcf43d AD	275	errout:
0ddcf43d AD	276	return err;
7a9bc9b8 DM	277	}
7a9bc9b8 DM	278
e1ef4bf2 TG	279	static int fib4_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
e1ef4bf2 TG	280	struct nlattr **tb)
1da177e4	281	{
e1ef4bf2	282	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	283
e1ef4bf2 TG	284	if (frh->src_len && (rule4->src_len != frh->src_len))
e1ef4bf2 TG	285	return 0;
1da177e4	286
e1ef4bf2 TG	287	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
e1ef4bf2 TG	288	return 0;
7b204afd	289
e1ef4bf2 TG	290	if (frh->tos && (rule4->tos != frh->tos))
e1ef4bf2 TG	291	return 0;
7b204afd	292
c7066f70	293	#ifdef CONFIG_IP_ROUTE_CLASSID
e1ef4bf2 TG	294	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
	295	return 0;
	296	#endif
1da177e4	297
67b61f6c	298	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
e1ef4bf2	299	return 0;
1da177e4	300
67b61f6c	301	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
e1ef4bf2	302	return 0;
1da177e4	303
e1ef4bf2	304	return 1;
1da177e4 LT	305	}
1da177e4 LT	306
e1ef4bf2	307	static int fib4_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	308	struct fib_rule_hdr *frh)
e1ef4bf2 TG	309	{
e1ef4bf2 TG	310	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	311
e1ef4bf2 TG	312	frh->dst_len = rule4->dst_len;
	313	frh->src_len = rule4->src_len;
	314	frh->tos = rule4->tos;
1da177e4	315
f3756b79	316	if ((rule4->dst_len &&
930345ea	317	nla_put_in_addr(skb, FRA_DST, rule4->dst)) \|\|
f3756b79	318	(rule4->src_len &&
930345ea	319	nla_put_in_addr(skb, FRA_SRC, rule4->src)))
f3756b79	320	goto nla_put_failure;
c7066f70	321	#ifdef CONFIG_IP_ROUTE_CLASSID
f3756b79 DM	322	if (rule4->tclassid &&
	323	nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
	324	goto nla_put_failure;
1da177e4	325	#endif
e1ef4bf2	326	return 0;
1da177e4	327
e1ef4bf2 TG	328	nla_put_failure:
e1ef4bf2 TG	329	return -ENOBUFS;
1da177e4 LT	330	}
1da177e4 LT	331
339bf98f TG	332	static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
	333	{
	334	return nla_total_size(4) /* dst */
	335	+ nla_total_size(4) /* src */
	336	+ nla_total_size(4); /* flow */
	337	}
	338
ae299fc0	339	static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
73417f61	340	{
bafa6d9d	341	rt_cache_flush(ops->fro_net);
73417f61 TG	342	}
73417f61 TG	343
04a6f82c	344	static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
25239cee	345	.family = AF_INET,
e1ef4bf2	346	.rule_size = sizeof(struct fib4_rule),
e1701c68	347	.addr_size = sizeof(u32),
e1ef4bf2	348	.action = fib4_rule_action,
7764a45a	349	.suppress = fib4_rule_suppress,
e1ef4bf2 TG	350	.match = fib4_rule_match,
e1ef4bf2 TG	351	.configure = fib4_rule_configure,
7a9bc9b8	352	.delete = fib4_rule_delete,
e1ef4bf2 TG	353	.compare = fib4_rule_compare,
e1ef4bf2 TG	354	.fill = fib4_rule_fill,
339bf98f	355	.nlmsg_payload = fib4_rule_nlmsg_payload,
73417f61	356	.flush_cache = fib4_rule_flush_cache,
e1ef4bf2 TG	357	.nlgroup = RTNLGRP_IPV4_RULE,
e1ef4bf2 TG	358	.policy = fib4_rule_policy,
e1ef4bf2 TG	359	.owner = THIS_MODULE,
	360	};
	361
e4e4971c	362	static int fib_default_rules_init(struct fib_rules_ops *ops)
1da177e4	363	{
2994c638 DL	364	int err;
2994c638 DL	365
5adef180	366	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
2994c638 DL	367	if (err < 0)
2994c638 DL	368	return err;
e4e4971c	369	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
2994c638 DL	370	if (err < 0)
2994c638 DL	371	return err;
e4e4971c	372	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
2994c638 DL	373	if (err < 0)
	374	return err;
	375	return 0;
	376	}
1da177e4	377
7b1a74fd	378	int __net_init fib4_rules_init(struct net *net)
2994c638	379	{
dbb50165	380	int err;
e4e4971c DL	381	struct fib_rules_ops *ops;
e4e4971c DL	382
e9c5158a EB	383	ops = fib_rules_register(&fib4_rules_ops_template, net);
	384	if (IS_ERR(ops))
	385	return PTR_ERR(ops);
dbb50165	386
e4e4971c	387	err = fib_default_rules_init(ops);
dbb50165 DL	388	if (err < 0)
dbb50165 DL	389	goto fail;
e4e4971c	390	net->ipv4.rules_ops = ops;
f4530fa5	391	net->ipv4.fib_has_custom_rules = false;
dbb50165 DL	392	return 0;
	393
	394	fail:
	395	/* also cleans all rules already added */
9e3a5487	396	fib_rules_unregister(ops);
dbb50165	397	return err;
1da177e4	398	}
7b1a74fd DL	399
	400	void __net_exit fib4_rules_exit(struct net *net)
	401	{
9e3a5487	402	fib_rules_unregister(net->ipv4.rules_ops);
7b1a74fd	403	}