[mirror_ubuntu-jammy-kernel.git] / net / ipv4 / fib_rules.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 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>
 *
 * 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/nexthop.h>
#include <net/fib_rules.h>
#include <linux/indirect_call_wrapper.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,
		    struct netlink_ext_ack *extack)
{
	return fib_rules_dump(net, nb, AF_INET, extack);
}

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);

INDIRECT_CALLABLE_SCOPE 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;
}

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

	if (result->fi) {
		struct fib_nh_common *nhc = fib_info_nhc(result->fi, 0);

		dev = nhc->nhc_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;
}

INDIRECT_CALLABLE_SCOPE 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;

	if (rule->ip_proto && (rule->ip_proto != fl4->flowi4_proto))
		return 0;

	if (fib_rule_port_range_set(&rule->sport_range) &&
	    !fib_rule_port_inrange(&rule->sport_range, fl4->fl4_sport))
		return 0;

	if (fib_rule_port_range_set(&rule->dport_range) &&
	    !fib_rule_port_inrange(&rule->dport_range, fl4->fl4_dport))
		return 0;

	return 1;
}

static struct fib_table *fib_empty_table(struct net *net)
{
	u32 id = 1;

	while (1) {
		if (!fib_get_table(net, id))
			return fib_new_table(net, id);

		if (id++ == RT_TABLE_MAX)
			break;
	}
	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 netlink_ext_ack *extack)
{
	struct net *net = sock_net(skb->sk);
	int err = -EINVAL;
	struct fib4_rule *rule4 = (struct fib4_rule *) rule;

	if (frh->tos & ~IPTOS_TOS_MASK) {
		NL_SET_ERR_MSG(extack, "Invalid tos");
		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)
			atomic_inc(&net->ipv4.fib_num_tclassid_users);
	}
#endif

	if (fib_rule_requires_fldissect(rule))
		net->ipv4.fib_rules_require_fldissect++;

	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)
		atomic_dec(&net->ipv4.fib_num_tclassid_users);
#endif
	net->ipv4.fib_has_custom_rules = true;

	if (net->ipv4.fib_rules_require_fldissect &&
	    fib_rule_requires_fldissect(rule))
		net->ipv4.fib_rules_require_fldissect--;
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;
	net->ipv4.fib_rules_require_fldissect = 0;
	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
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* INET An implementation of the TCP/IP protocol suite for the LINUX
	4	* operating system. INET is implemented using the BSD Socket
	5	* interface as the means of communication with the user level.
	6	*
	7	* IPv4 Forwarding Information Base: policy rules.
	8	*
1da177e4	9	* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6a31d2a9	10	* Thomas Graf <tgraf@suug.ch>
1da177e4	11	*
1da177e4	12	* Fixes:
6a31d2a9	13	* Rani Assaf : local_rule cannot be deleted
1da177e4 LT	14	* Marc Boucher : routing by fwmark
	15	*/
	16
1da177e4 LT	17	#include <linux/types.h>
1da177e4 LT	18	#include <linux/kernel.h>
1da177e4	19	#include <linux/netdevice.h>
1da177e4	20	#include <linux/netlink.h>
e1ef4bf2	21	#include <linux/inetdevice.h>
1da177e4	22	#include <linux/init.h>
7b204afd RO	23	#include <linux/list.h>
7b204afd RO	24	#include <linux/rcupdate.h>
bc3b2d7f	25	#include <linux/export.h>
1da177e4	26	#include <net/ip.h>
1da177e4 LT	27	#include <net/route.h>
1da177e4 LT	28	#include <net/tcp.h>
1da177e4	29	#include <net/ip_fib.h>
5481d73f	30	#include <net/nexthop.h>
e1ef4bf2	31	#include <net/fib_rules.h>
b9aaec8f	32	#include <linux/indirect_call_wrapper.h>
1da177e4	33
6a31d2a9	34	struct fib4_rule {
e1ef4bf2 TG	35	struct fib_rule common;
	36	u8 dst_len;
	37	u8 src_len;
	38	u8 tos;
81f7bf6c AV	39	__be32 src;
	40	__be32 srcmask;
	41	__be32 dst;
	42	__be32 dstmask;
c7066f70	43	#ifdef CONFIG_IP_ROUTE_CLASSID
e1ef4bf2	44	u32 tclassid;
1da177e4	45	#endif
1da177e4 LT	46	};
1da177e4 LT	47
3c71006d IS	48	static bool fib4_rule_matchall(const struct fib_rule *rule)
	49	{
	50	struct fib4_rule *r = container_of(rule, struct fib4_rule, common);
	51
	52	if (r->dst_len \|\| r->src_len \|\| r->tos)
	53	return false;
	54	return fib_rule_matchall(rule);
	55	}
	56
	57	bool fib4_rule_default(const struct fib_rule *rule)
	58	{
	59	if (!fib4_rule_matchall(rule) \|\| rule->action != FR_ACT_TO_TBL \|\|
	60	rule->l3mdev)
	61	return false;
	62	if (rule->table != RT_TABLE_LOCAL && rule->table != RT_TABLE_MAIN &&
	63	rule->table != RT_TABLE_DEFAULT)
	64	return false;
	65	return true;
	66	}
	67	EXPORT_SYMBOL_GPL(fib4_rule_default);
	68
b7a59557 JP	69	int fib4_rules_dump(struct net net, struct notifier_block nb,
b7a59557 JP	70	struct netlink_ext_ack *extack)
1b2a4440	71	{
b7a59557	72	return fib_rules_dump(net, nb, AF_INET, extack);
1b2a4440 IS	73	}
	74
	75	unsigned int fib4_rules_seq_read(struct net *net)
	76	{
	77	return fib_rules_seq_read(net, AF_INET);
	78	}
	79
0eeb075f AG	80	int __fib_lookup(struct net net, struct flowi4 flp,
0eeb075f AG	81	struct fib_result *res, unsigned int flags)
e1ef4bf2 TG	82	{
	83	struct fib_lookup_arg arg = {
	84	.result = res,
0eeb075f	85	.flags = flags,
e1ef4bf2 TG	86	};
e1ef4bf2 TG	87	int err;
1da177e4	88
9ee0034b DA	89	/* update flow if oif or iif point to device enslaved to l3mdev */
	90	l3mdev_update_flow(net, flowi4_to_flowi(flp));
	91
22bd5b9b	92	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
85b91b03 DM	93	#ifdef CONFIG_IP_ROUTE_CLASSID
	94	if (arg.rule)
	95	res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
	96	else
	97	res->tclassid = 0;
	98	#endif
49dd18ba PM	99
	100	if (err == -ESRCH)
	101	err = -ENETUNREACH;
	102
e1ef4bf2 TG	103	return err;
e1ef4bf2 TG	104	}
f4530fa5	105	EXPORT_SYMBOL_GPL(__fib_lookup);
e1ef4bf2	106
b9aaec8f BV	107	INDIRECT_CALLABLE_SCOPE int fib4_rule_action(struct fib_rule *rule,
	108	struct flowi *flp, int flags,
	109	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
b9aaec8f	143	INDIRECT_CALLABLE_SCOPE bool fib4_rule_suppress(struct fib_rule *rule,
b3427aa9	144	int flags,
b9aaec8f	145	struct fib_lookup_arg *arg)
7764a45a	146	{
6ef94cfa	147	struct fib_result result = (struct fib_result ) arg->result;
673498b8 ST	148	struct net_device *dev = NULL;
673498b8 ST	149
5481d73f	150	if (result->fi) {
dcb1ecb5	151	struct fib_nh_common *nhc = fib_info_nhc(result->fi, 0);
5481d73f	152
dcb1ecb5	153	dev = nhc->nhc_dev;
5481d73f	154	}
6ef94cfa	155
7764a45a ST	156	/* do not accept result if the route does
	157	* not meet the required prefix length
	158	*/
73f5698e	159	if (result->prefixlen <= rule->suppress_prefixlen)
6ef94cfa ST	160	goto suppress_route;
	161
	162	/* do not accept result if the route uses a device
	163	* belonging to a forbidden interface group
	164	*/
	165	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	166	goto suppress_route;
	167
7764a45a	168	return false;
6ef94cfa ST	169
	170	suppress_route:
	171	if (!(arg->flags & FIB_LOOKUP_NOREF))
	172	fib_info_put(result->fi);
	173	return true;
7764a45a	174	}
e1ef4bf2	175
b9aaec8f BV	176	INDIRECT_CALLABLE_SCOPE int fib4_rule_match(struct fib_rule *rule,
b9aaec8f BV	177	struct flowi *fl, int flags)
e1ef4bf2 TG	178	{
e1ef4bf2 TG	179	struct fib4_rule r = (struct fib4_rule ) rule;
9ade2286 DM	180	struct flowi4 *fl4 = &fl->u.ip4;
	181	__be32 daddr = fl4->daddr;
	182	__be32 saddr = fl4->saddr;
e1ef4bf2 TG	183
	184	if (((saddr ^ r->src) & r->srcmask) \|\|
	185	((daddr ^ r->dst) & r->dstmask))
	186	return 0;
	187
9ade2286	188	if (r->tos && (r->tos != fl4->flowi4_tos))
e1ef4bf2 TG	189	return 0;
e1ef4bf2 TG	190
4a2d73a4 RP	191	if (rule->ip_proto && (rule->ip_proto != fl4->flowi4_proto))
	192	return 0;
	193
	194	if (fib_rule_port_range_set(&rule->sport_range) &&
	195	!fib_rule_port_inrange(&rule->sport_range, fl4->fl4_sport))
	196	return 0;
	197
	198	if (fib_rule_port_range_set(&rule->dport_range) &&
	199	!fib_rule_port_inrange(&rule->dport_range, fl4->fl4_dport))
	200	return 0;
	201
e1ef4bf2 TG	202	return 1;
e1ef4bf2 TG	203	}
1da177e4	204
8ad4942c	205	static struct fib_table fib_empty_table(struct net net)
1da177e4	206	{
58075ff5	207	u32 id = 1;
1da177e4	208
58075ff5	209	while (1) {
51456b29	210	if (!fib_get_table(net, id))
8ad4942c	211	return fib_new_table(net, id);
58075ff5 Y	212
	213	if (id++ == RT_TABLE_MAX)
	214	break;
	215	}
1da177e4 LT	216	return NULL;
	217	}
	218
ef7c79ed	219	static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
1f6c9557	220	FRA_GENERIC_POLICY,
e1ef4bf2 TG	221	[FRA_FLOW] = { .type = NLA_U32 },
e1ef4bf2 TG	222	};
7b204afd	223
e1ef4bf2	224	static int fib4_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	225	struct fib_rule_hdr *frh,
b16fb418 RP	226	struct nlattr **tb,
b16fb418 RP	227	struct netlink_ext_ack *extack)
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
b16fb418 RP	233	if (frh->tos & ~IPTOS_TOS_MASK) {
b16fb418 RP	234	NL_SET_ERR_MSG(extack, "Invalid tos");
e1ef4bf2	235	goto errout;
b16fb418	236	}
7b204afd	237
0ddcf43d AD	238	/* split local/main if they are not already split */
	239	err = fib_unmerge(net);
	240	if (err)
	241	goto errout;
	242
96c63fa7	243	if (rule->table == RT_TABLE_UNSPEC && !rule->l3mdev) {
e1ef4bf2 TG	244	if (rule->action == FR_ACT_TO_TBL) {
e1ef4bf2 TG	245	struct fib_table *table;
1da177e4	246
e4e4971c	247	table = fib_empty_table(net);
51456b29	248	if (!table) {
e1ef4bf2 TG	249	err = -ENOBUFS;
	250	goto errout;
	251	}
1da177e4	252
e1ef4bf2	253	rule->table = table->tb_id;
1da177e4 LT	254	}
	255	}
	256
e1701c68	257	if (frh->src_len)
67b61f6c	258	rule4->src = nla_get_in_addr(tb[FRA_SRC]);
7b204afd	259
e1701c68	260	if (frh->dst_len)
67b61f6c	261	rule4->dst = nla_get_in_addr(tb[FRA_DST]);
7b204afd	262
c7066f70	263	#ifdef CONFIG_IP_ROUTE_CLASSID
7a9bc9b8	264	if (tb[FRA_FLOW]) {
e1ef4bf2	265	rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
7a9bc9b8	266	if (rule4->tclassid)
97ca3f1a	267	atomic_inc(&net->ipv4.fib_num_tclassid_users);
7a9bc9b8	268	}
1da177e4 LT	269	#endif
1da177e4 LT	270
e37b1e97 RP	271	if (fib_rule_requires_fldissect(rule))
	272	net->ipv4.fib_rules_require_fldissect++;
	273
e1ef4bf2 TG	274	rule4->src_len = frh->src_len;
	275	rule4->srcmask = inet_make_mask(rule4->src_len);
	276	rule4->dst_len = frh->dst_len;
	277	rule4->dstmask = inet_make_mask(rule4->dst_len);
	278	rule4->tos = frh->tos;
7b204afd	279
f4530fa5	280	net->ipv4.fib_has_custom_rules = true;
104616e7	281
e1ef4bf2 TG	282	err = 0;
	283	errout:
	284	return err;
1da177e4 LT	285	}
1da177e4 LT	286
0ddcf43d	287	static int fib4_rule_delete(struct fib_rule *rule)
7a9bc9b8	288	{
f4530fa5	289	struct net *net = rule->fr_net;
0ddcf43d	290	int err;
7a9bc9b8	291
0ddcf43d AD	292	/* split local/main if they are not already split */
	293	err = fib_unmerge(net);
	294	if (err)
	295	goto errout;
	296
	297	#ifdef CONFIG_IP_ROUTE_CLASSID
	298	if (((struct fib4_rule *)rule)->tclassid)
97ca3f1a	299	atomic_dec(&net->ipv4.fib_num_tclassid_users);
7a9bc9b8	300	#endif
f4530fa5	301	net->ipv4.fib_has_custom_rules = true;
e37b1e97 RP	302
	303	if (net->ipv4.fib_rules_require_fldissect &&
	304	fib_rule_requires_fldissect(rule))
	305	net->ipv4.fib_rules_require_fldissect--;
0ddcf43d AD	306	errout:
0ddcf43d AD	307	return err;
7a9bc9b8 DM	308	}
7a9bc9b8 DM	309
e1ef4bf2 TG	310	static int fib4_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
e1ef4bf2 TG	311	struct nlattr **tb)
1da177e4	312	{
e1ef4bf2	313	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	314
e1ef4bf2 TG	315	if (frh->src_len && (rule4->src_len != frh->src_len))
e1ef4bf2 TG	316	return 0;
1da177e4	317
e1ef4bf2 TG	318	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
e1ef4bf2 TG	319	return 0;
7b204afd	320
e1ef4bf2 TG	321	if (frh->tos && (rule4->tos != frh->tos))
e1ef4bf2 TG	322	return 0;
7b204afd	323
c7066f70	324	#ifdef CONFIG_IP_ROUTE_CLASSID
e1ef4bf2 TG	325	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
	326	return 0;
	327	#endif
1da177e4	328
67b61f6c	329	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
e1ef4bf2	330	return 0;
1da177e4	331
67b61f6c	332	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
e1ef4bf2	333	return 0;
1da177e4	334
e1ef4bf2	335	return 1;
1da177e4 LT	336	}
1da177e4 LT	337
e1ef4bf2	338	static int fib4_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	339	struct fib_rule_hdr *frh)
e1ef4bf2 TG	340	{
e1ef4bf2 TG	341	struct fib4_rule rule4 = (struct fib4_rule ) rule;
1da177e4	342
e1ef4bf2 TG	343	frh->dst_len = rule4->dst_len;
	344	frh->src_len = rule4->src_len;
	345	frh->tos = rule4->tos;
1da177e4	346
f3756b79	347	if ((rule4->dst_len &&
930345ea	348	nla_put_in_addr(skb, FRA_DST, rule4->dst)) \|\|
f3756b79	349	(rule4->src_len &&
930345ea	350	nla_put_in_addr(skb, FRA_SRC, rule4->src)))
f3756b79	351	goto nla_put_failure;
c7066f70	352	#ifdef CONFIG_IP_ROUTE_CLASSID
f3756b79 DM	353	if (rule4->tclassid &&
	354	nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
	355	goto nla_put_failure;
1da177e4	356	#endif
e1ef4bf2	357	return 0;
1da177e4	358
e1ef4bf2 TG	359	nla_put_failure:
e1ef4bf2 TG	360	return -ENOBUFS;
1da177e4 LT	361	}
1da177e4 LT	362
339bf98f TG	363	static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
	364	{
	365	return nla_total_size(4) /* dst */
	366	+ nla_total_size(4) /* src */
	367	+ nla_total_size(4); /* flow */
	368	}
	369
ae299fc0	370	static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
73417f61	371	{
bafa6d9d	372	rt_cache_flush(ops->fro_net);
73417f61 TG	373	}
73417f61 TG	374
04a6f82c	375	static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
25239cee	376	.family = AF_INET,
e1ef4bf2	377	.rule_size = sizeof(struct fib4_rule),
e1701c68	378	.addr_size = sizeof(u32),
e1ef4bf2	379	.action = fib4_rule_action,
7764a45a	380	.suppress = fib4_rule_suppress,
e1ef4bf2 TG	381	.match = fib4_rule_match,
e1ef4bf2 TG	382	.configure = fib4_rule_configure,
7a9bc9b8	383	.delete = fib4_rule_delete,
e1ef4bf2 TG	384	.compare = fib4_rule_compare,
e1ef4bf2 TG	385	.fill = fib4_rule_fill,
339bf98f	386	.nlmsg_payload = fib4_rule_nlmsg_payload,
73417f61	387	.flush_cache = fib4_rule_flush_cache,
e1ef4bf2 TG	388	.nlgroup = RTNLGRP_IPV4_RULE,
e1ef4bf2 TG	389	.policy = fib4_rule_policy,
e1ef4bf2 TG	390	.owner = THIS_MODULE,
	391	};
	392
e4e4971c	393	static int fib_default_rules_init(struct fib_rules_ops *ops)
1da177e4	394	{
2994c638 DL	395	int err;
2994c638 DL	396
5adef180	397	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
2994c638 DL	398	if (err < 0)
2994c638 DL	399	return err;
e4e4971c	400	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
2994c638 DL	401	if (err < 0)
2994c638 DL	402	return err;
e4e4971c	403	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
2994c638 DL	404	if (err < 0)
	405	return err;
	406	return 0;
	407	}
1da177e4	408
7b1a74fd	409	int __net_init fib4_rules_init(struct net *net)
2994c638	410	{
dbb50165	411	int err;
e4e4971c DL	412	struct fib_rules_ops *ops;
e4e4971c DL	413
e9c5158a EB	414	ops = fib_rules_register(&fib4_rules_ops_template, net);
	415	if (IS_ERR(ops))
	416	return PTR_ERR(ops);
dbb50165	417
e4e4971c	418	err = fib_default_rules_init(ops);
dbb50165 DL	419	if (err < 0)
dbb50165 DL	420	goto fail;
e4e4971c	421	net->ipv4.rules_ops = ops;
f4530fa5	422	net->ipv4.fib_has_custom_rules = false;
e37b1e97	423	net->ipv4.fib_rules_require_fldissect = 0;
dbb50165 DL	424	return 0;
	425
	426	fail:
	427	/* also cleans all rules already added */
9e3a5487	428	fib_rules_unregister(ops);
dbb50165	429	return err;
1da177e4	430	}
7b1a74fd DL	431
	432	void __net_exit fib4_rules_exit(struct net *net)
	433	{
9e3a5487	434	fib_rules_unregister(net->ipv4.rules_ops);
7b1a74fd	435	}