[mirror_ubuntu-artful-kernel.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 __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 int call_fib_rule_notifier(struct notifier_block *nb, struct net *net,
				  enum fib_event_type event_type,
				  struct fib_rule *rule)
{
	struct fib_rule_notifier_info info = {
		.rule = rule,
	};

	return call_fib_notifier(nb, net, event_type, &info.info);
}

static int call_fib_rule_notifiers(struct net *net,
				   enum fib_event_type event_type,
				   struct fib_rule *rule)
{
	struct fib_rule_notifier_info info = {
		.rule = rule,
	};

	return call_fib_notifiers(net, event_type, &info.info);
}

/* Called with rcu_read_lock() */
void fib_rules_notify(struct net *net, struct notifier_block *nb)
{
	struct fib_rules_ops *ops = net->ipv4.rules_ops;
	struct fib_rule *rule;

	list_for_each_entry_rcu(rule, &ops->rules_list, list)
		call_fib_rule_notifier(nb, net, FIB_EVENT_RULE_ADD, rule);
}

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;
	call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule);

	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;
	call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule);
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
0eeb075f AG	71	int __fib_lookup(struct net net, struct flowi4 flp,
0eeb075f AG	72	struct fib_result *res, unsigned int flags)
e1ef4bf2 TG	73	{
	74	struct fib_lookup_arg arg = {
	75	.result = res,
0eeb075f	76	.flags = flags,
e1ef4bf2 TG	77	};
e1ef4bf2 TG	78	int err;
1da177e4	79
9ee0034b DA	80	/* update flow if oif or iif point to device enslaved to l3mdev */
	81	l3mdev_update_flow(net, flowi4_to_flowi(flp));
	82
22bd5b9b	83	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
85b91b03 DM	84	#ifdef CONFIG_IP_ROUTE_CLASSID
	85	if (arg.rule)
	86	res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
	87	else
	88	res->tclassid = 0;
	89	#endif
49dd18ba PM	90
	91	if (err == -ESRCH)
	92	err = -ENETUNREACH;
	93
e1ef4bf2 TG	94	return err;
e1ef4bf2 TG	95	}
f4530fa5	96	EXPORT_SYMBOL_GPL(__fib_lookup);
e1ef4bf2	97
8ce11e6a AB	98	static int fib4_rule_action(struct fib_rule rule, struct flowi flp,
8ce11e6a AB	99	int flags, struct fib_lookup_arg *arg)
1da177e4	100	{
e1ef4bf2 TG	101	int err = -EAGAIN;
e1ef4bf2 TG	102	struct fib_table *tbl;
96c63fa7	103	u32 tb_id;
e1ef4bf2 TG	104
	105	switch (rule->action) {
	106	case FR_ACT_TO_TBL:
	107	break;
	108
	109	case FR_ACT_UNREACHABLE:
345e9b54	110	return -ENETUNREACH;
e1ef4bf2 TG	111
e1ef4bf2 TG	112	case FR_ACT_PROHIBIT:
345e9b54	113	return -EACCES;
e1ef4bf2 TG	114
	115	case FR_ACT_BLACKHOLE:
	116	default:
345e9b54	117	return -EINVAL;
1da177e4	118	}
e1ef4bf2	119
345e9b54 AD	120	rcu_read_lock();
345e9b54 AD	121
96c63fa7 DA	122	tb_id = fib_rule_get_table(rule, arg);
96c63fa7 DA	123	tbl = fib_get_table(rule->fr_net, tb_id);
345e9b54 AD	124	if (tbl)
	125	err = fib_table_lookup(tbl, &flp->u.ip4,
	126	(struct fib_result *)arg->result,
	127	arg->flags);
e1ef4bf2	128
345e9b54	129	rcu_read_unlock();
1da177e4 LT	130	return err;
	131	}
	132
7764a45a ST	133	static bool fib4_rule_suppress(struct fib_rule rule, struct fib_lookup_arg arg)
7764a45a ST	134	{
6ef94cfa	135	struct fib_result result = (struct fib_result ) arg->result;
673498b8 ST	136	struct net_device *dev = NULL;
	137
	138	if (result->fi)
	139	dev = result->fi->fib_dev;
6ef94cfa	140
7764a45a ST	141	/* do not accept result if the route does
	142	* not meet the required prefix length
	143	*/
73f5698e	144	if (result->prefixlen <= rule->suppress_prefixlen)
6ef94cfa ST	145	goto suppress_route;
	146
	147	/* do not accept result if the route uses a device
	148	* belonging to a forbidden interface group
	149	*/
	150	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	151	goto suppress_route;
	152
7764a45a	153	return false;
6ef94cfa ST	154
	155	suppress_route:
	156	if (!(arg->flags & FIB_LOOKUP_NOREF))
	157	fib_info_put(result->fi);
	158	return true;
7764a45a	159	}
e1ef4bf2	160
e1ef4bf2 TG	161	static int fib4_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	162	{
	163	struct fib4_rule r = (struct fib4_rule ) rule;
9ade2286 DM	164	struct flowi4 *fl4 = &fl->u.ip4;
	165	__be32 daddr = fl4->daddr;
	166	__be32 saddr = fl4->saddr;
e1ef4bf2 TG	167
	168	if (((saddr ^ r->src) & r->srcmask) \|\|
	169	((daddr ^ r->dst) & r->dstmask))
	170	return 0;
	171
9ade2286	172	if (r->tos && (r->tos != fl4->flowi4_tos))
e1ef4bf2 TG	173	return 0;
e1ef4bf2 TG	174
e1ef4bf2 TG	175	return 1;
e1ef4bf2 TG	176	}
1da177e4	177
8ad4942c	178	static struct fib_table fib_empty_table(struct net net)
1da177e4	179	{
2dfe55b4	180	u32 id;
1da177e4 LT	181
1da177e4 LT	182	for (id = 1; id <= RT_TABLE_MAX; id++)
51456b29	183	if (!fib_get_table(net, id))
8ad4942c	184	return fib_new_table(net, id);
1da177e4 LT	185	return NULL;
	186	}
	187
5d7bfd14 IS	188	static int call_fib_rule_notifier(struct notifier_block nb, struct net net,
	189	enum fib_event_type event_type,
	190	struct fib_rule *rule)
	191	{
	192	struct fib_rule_notifier_info info = {
	193	.rule = rule,
	194	};
	195
	196	return call_fib_notifier(nb, net, event_type, &info.info);
	197	}
	198
b90eb754	199	static int call_fib_rule_notifiers(struct net *net,
6a003a5f IS	200	enum fib_event_type event_type,
6a003a5f IS	201	struct fib_rule *rule)
b90eb754	202	{
6a003a5f IS	203	struct fib_rule_notifier_info info = {
	204	.rule = rule,
	205	};
b90eb754	206
6a003a5f	207	return call_fib_notifiers(net, event_type, &info.info);
b90eb754 JP	208	}
b90eb754 JP	209
5d7bfd14	210	/* Called with rcu_read_lock() */
d05f7a7d	211	void fib_rules_notify(struct net net, struct notifier_block nb)
c0243892	212	{
5d7bfd14 IS	213	struct fib_rules_ops *ops = net->ipv4.rules_ops;
5d7bfd14 IS	214	struct fib_rule *rule;
c0243892	215
5d7bfd14 IS	216	list_for_each_entry_rcu(rule, &ops->rules_list, list)
5d7bfd14 IS	217	call_fib_rule_notifier(nb, net, FIB_EVENT_RULE_ADD, rule);
c0243892 IS	218	}
c0243892 IS	219
ef7c79ed	220	static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
1f6c9557	221	FRA_GENERIC_POLICY,
e1ef4bf2 TG	222	[FRA_FLOW] = { .type = NLA_U32 },
e1ef4bf2 TG	223	};
7b204afd	224
e1ef4bf2	225	static int fib4_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	226	struct fib_rule_hdr *frh,
e1ef4bf2	227	struct nlattr **tb)
1da177e4	228	{
3b1e0a65	229	struct net *net = sock_net(skb->sk);
e1ef4bf2 TG	230	int err = -EINVAL;
e1ef4bf2 TG	231	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	232
e1701c68	233	if (frh->tos & ~IPTOS_TOS_MASK)
e1ef4bf2	234	goto errout;
7b204afd	235
0ddcf43d AD	236	/* split local/main if they are not already split */
	237	err = fib_unmerge(net);
	238	if (err)
	239	goto errout;
	240
96c63fa7	241	if (rule->table == RT_TABLE_UNSPEC && !rule->l3mdev) {
e1ef4bf2 TG	242	if (rule->action == FR_ACT_TO_TBL) {
e1ef4bf2 TG	243	struct fib_table *table;
1da177e4	244
e4e4971c	245	table = fib_empty_table(net);
51456b29	246	if (!table) {
e1ef4bf2 TG	247	err = -ENOBUFS;
	248	goto errout;
	249	}
1da177e4	250
e1ef4bf2	251	rule->table = table->tb_id;
1da177e4 LT	252	}
	253	}
	254
e1701c68	255	if (frh->src_len)
67b61f6c	256	rule4->src = nla_get_in_addr(tb[FRA_SRC]);
7b204afd	257
e1701c68	258	if (frh->dst_len)
67b61f6c	259	rule4->dst = nla_get_in_addr(tb[FRA_DST]);
7b204afd	260
c7066f70	261	#ifdef CONFIG_IP_ROUTE_CLASSID
7a9bc9b8	262	if (tb[FRA_FLOW]) {
e1ef4bf2	263	rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
7a9bc9b8	264	if (rule4->tclassid)
f4530fa5	265	net->ipv4.fib_num_tclassid_users++;
7a9bc9b8	266	}
1da177e4 LT	267	#endif
1da177e4 LT	268
e1ef4bf2 TG	269	rule4->src_len = frh->src_len;
	270	rule4->srcmask = inet_make_mask(rule4->src_len);
	271	rule4->dst_len = frh->dst_len;
	272	rule4->dstmask = inet_make_mask(rule4->dst_len);
	273	rule4->tos = frh->tos;
7b204afd	274
f4530fa5	275	net->ipv4.fib_has_custom_rules = true;
6a003a5f	276	call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule);
104616e7	277
e1ef4bf2 TG	278	err = 0;
	279	errout:
	280	return err;
1da177e4 LT	281	}
1da177e4 LT	282
0ddcf43d	283	static int fib4_rule_delete(struct fib_rule *rule)
7a9bc9b8	284	{
f4530fa5	285	struct net *net = rule->fr_net;
0ddcf43d	286	int err;
7a9bc9b8	287
0ddcf43d AD	288	/* split local/main if they are not already split */
	289	err = fib_unmerge(net);
	290	if (err)
	291	goto errout;
	292
	293	#ifdef CONFIG_IP_ROUTE_CLASSID
	294	if (((struct fib4_rule *)rule)->tclassid)
f4530fa5	295	net->ipv4.fib_num_tclassid_users--;
7a9bc9b8	296	#endif
f4530fa5	297	net->ipv4.fib_has_custom_rules = true;
6a003a5f	298	call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule);
0ddcf43d AD	299	errout:
0ddcf43d AD	300	return err;
7a9bc9b8 DM	301	}
7a9bc9b8 DM	302
e1ef4bf2 TG	303	static int fib4_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
e1ef4bf2 TG	304	struct nlattr **tb)
1da177e4	305	{
e1ef4bf2	306	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	307
e1ef4bf2 TG	308	if (frh->src_len && (rule4->src_len != frh->src_len))
e1ef4bf2 TG	309	return 0;
1da177e4	310
e1ef4bf2 TG	311	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
e1ef4bf2 TG	312	return 0;
7b204afd	313
e1ef4bf2 TG	314	if (frh->tos && (rule4->tos != frh->tos))
e1ef4bf2 TG	315	return 0;
7b204afd	316
c7066f70	317	#ifdef CONFIG_IP_ROUTE_CLASSID
e1ef4bf2 TG	318	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
	319	return 0;
	320	#endif
1da177e4	321
67b61f6c	322	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
e1ef4bf2	323	return 0;
1da177e4	324
67b61f6c	325	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
e1ef4bf2	326	return 0;
1da177e4	327
e1ef4bf2	328	return 1;
1da177e4 LT	329	}
1da177e4 LT	330
e1ef4bf2	331	static int fib4_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	332	struct fib_rule_hdr *frh)
e1ef4bf2 TG	333	{
e1ef4bf2 TG	334	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	335
e1ef4bf2 TG	336	frh->dst_len = rule4->dst_len;
	337	frh->src_len = rule4->src_len;
	338	frh->tos = rule4->tos;
1da177e4	339
f3756b79	340	if ((rule4->dst_len &&
930345ea	341	nla_put_in_addr(skb, FRA_DST, rule4->dst)) \|\|
f3756b79	342	(rule4->src_len &&
930345ea	343	nla_put_in_addr(skb, FRA_SRC, rule4->src)))
f3756b79	344	goto nla_put_failure;
c7066f70	345	#ifdef CONFIG_IP_ROUTE_CLASSID
f3756b79 DM	346	if (rule4->tclassid &&
	347	nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
	348	goto nla_put_failure;
1da177e4	349	#endif
e1ef4bf2	350	return 0;
1da177e4	351
e1ef4bf2 TG	352	nla_put_failure:
e1ef4bf2 TG	353	return -ENOBUFS;
1da177e4 LT	354	}
1da177e4 LT	355
339bf98f TG	356	static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
	357	{
	358	return nla_total_size(4) /* dst */
	359	+ nla_total_size(4) /* src */
	360	+ nla_total_size(4); /* flow */
	361	}
	362
ae299fc0	363	static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
73417f61	364	{
bafa6d9d	365	rt_cache_flush(ops->fro_net);
73417f61 TG	366	}
73417f61 TG	367
04a6f82c	368	static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
25239cee	369	.family = AF_INET,
e1ef4bf2	370	.rule_size = sizeof(struct fib4_rule),
e1701c68	371	.addr_size = sizeof(u32),
e1ef4bf2	372	.action = fib4_rule_action,
7764a45a	373	.suppress = fib4_rule_suppress,
e1ef4bf2 TG	374	.match = fib4_rule_match,
e1ef4bf2 TG	375	.configure = fib4_rule_configure,
7a9bc9b8	376	.delete = fib4_rule_delete,
e1ef4bf2 TG	377	.compare = fib4_rule_compare,
e1ef4bf2 TG	378	.fill = fib4_rule_fill,
339bf98f	379	.nlmsg_payload = fib4_rule_nlmsg_payload,
73417f61	380	.flush_cache = fib4_rule_flush_cache,
e1ef4bf2 TG	381	.nlgroup = RTNLGRP_IPV4_RULE,
e1ef4bf2 TG	382	.policy = fib4_rule_policy,
e1ef4bf2 TG	383	.owner = THIS_MODULE,
	384	};
	385
e4e4971c	386	static int fib_default_rules_init(struct fib_rules_ops *ops)
1da177e4	387	{
2994c638 DL	388	int err;
2994c638 DL	389
5adef180	390	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
2994c638 DL	391	if (err < 0)
2994c638 DL	392	return err;
e4e4971c	393	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
2994c638 DL	394	if (err < 0)
2994c638 DL	395	return err;
e4e4971c	396	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
2994c638 DL	397	if (err < 0)
	398	return err;
	399	return 0;
	400	}
1da177e4	401
7b1a74fd	402	int __net_init fib4_rules_init(struct net *net)
2994c638	403	{
dbb50165	404	int err;
e4e4971c DL	405	struct fib_rules_ops *ops;
e4e4971c DL	406
e9c5158a EB	407	ops = fib_rules_register(&fib4_rules_ops_template, net);
	408	if (IS_ERR(ops))
	409	return PTR_ERR(ops);
dbb50165	410
e4e4971c	411	err = fib_default_rules_init(ops);
dbb50165 DL	412	if (err < 0)
dbb50165 DL	413	goto fail;
e4e4971c	414	net->ipv4.rules_ops = ops;
f4530fa5	415	net->ipv4.fib_has_custom_rules = false;
dbb50165 DL	416	return 0;
	417
	418	fail:
	419	/* also cleans all rules already added */
9e3a5487	420	fib_rules_unregister(ops);
dbb50165	421	return err;
1da177e4	422	}
7b1a74fd DL	423
	424	void __net_exit fib4_rules_exit(struct net *net)
	425	{
9e3a5487	426	fib_rules_unregister(net->ipv4.rules_ops);
7b1a74fd	427	}