[net-next-2.6.git] / net / ipv6 / fib6_rules.c

/*
 * net/ipv6/fib6_rules.c	IPv6 Routing Policy Rules
 *
 * Copyright (C)2003-2006 Helsinki University of Technology
 * Copyright (C)2003-2006 USAGI/WIDE Project
 *
 *	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, version 2.
 *
 * Authors
 *	Thomas Graf		<tgraf@suug.ch>
 *	Ville Nuorvala		<vnuorval@tcs.hut.fi>
 */

#include <linux/netdevice.h>

#include <net/fib_rules.h>
#include <net/ipv6.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include <net/netlink.h>

struct fib6_rule
{
	struct fib_rule		common;
	struct rt6key		src;
	struct rt6key		dst;
	u8			tclass;
};

static struct fib_rules_ops *fib6_rules_ops;

struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi *fl,
				   int flags, pol_lookup_t lookup)
{
	struct fib_lookup_arg arg = {
		.lookup_ptr = lookup,
	};

	fib_rules_lookup(fib6_rules_ops, fl, flags, &arg);
	if (arg.rule)
		fib_rule_put(arg.rule);

	if (arg.result)
		return arg.result;

	dst_hold(&ip6_null_entry.u.dst);
	return &ip6_null_entry.u.dst;
}

static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
			    int flags, struct fib_lookup_arg *arg)
{
	struct rt6_info *rt = NULL;
	struct fib6_table *table;
	pol_lookup_t lookup = arg->lookup_ptr;

	switch (rule->action) {
	case FR_ACT_TO_TBL:
		break;
	case FR_ACT_UNREACHABLE:
		rt = &ip6_null_entry;
		goto discard_pkt;
	default:
	case FR_ACT_BLACKHOLE:
		rt = &ip6_blk_hole_entry;
		goto discard_pkt;
	case FR_ACT_PROHIBIT:
		rt = &ip6_prohibit_entry;
		goto discard_pkt;
	}

	table = fib6_get_table(&init_net, rule->table);
	if (table)
		rt = lookup(table, flp, flags);

	if (rt != &ip6_null_entry) {
		struct fib6_rule *r = (struct fib6_rule *)rule;

		/*
		 * If we need to find a source address for this traffic,
		 * we check the result if it meets requirement of the rule.
		 */
		if ((rule->flags & FIB_RULE_FIND_SADDR) &&
		    r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
			struct in6_addr saddr;
			if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev,
					       &flp->fl6_dst, &saddr))
				goto again;
			if (!ipv6_prefix_equal(&saddr, &r->src.addr,
					       r->src.plen))
				goto again;
			ipv6_addr_copy(&flp->fl6_src, &saddr);
		}
		goto out;
	}
again:
	dst_release(&rt->u.dst);
	rt = NULL;
	goto out;

discard_pkt:
	dst_hold(&rt->u.dst);
out:
	arg->result = rt;
	return rt == NULL ? -EAGAIN : 0;
}


static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
{
	struct fib6_rule *r = (struct fib6_rule *) rule;

	if (r->dst.plen &&
	    !ipv6_prefix_equal(&fl->fl6_dst, &r->dst.addr, r->dst.plen))
		return 0;

	/*
	 * If FIB_RULE_FIND_SADDR is set and we do not have a
	 * source address for the traffic, we defer check for
	 * source address.
	 */
	if (r->src.plen) {
		if (flags & RT6_LOOKUP_F_HAS_SADDR) {
			if (!ipv6_prefix_equal(&fl->fl6_src, &r->src.addr,
					       r->src.plen))
				return 0;
		} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
			return 0;
	}

	if (r->tclass && r->tclass != ((ntohl(fl->fl6_flowlabel) >> 20) & 0xff))
		return 0;

	return 1;
}

static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
	FRA_GENERIC_POLICY,
};

static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
			       struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
			       struct nlattr **tb)
{
	int err = -EINVAL;
	struct fib6_rule *rule6 = (struct fib6_rule *) rule;

	if (rule->action == FR_ACT_TO_TBL) {
		if (rule->table == RT6_TABLE_UNSPEC)
			goto errout;

		if (fib6_new_table(&init_net, rule->table) == NULL) {
			err = -ENOBUFS;
			goto errout;
		}
	}

	if (frh->src_len)
		nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
			   sizeof(struct in6_addr));

	if (frh->dst_len)
		nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
			   sizeof(struct in6_addr));

	rule6->src.plen = frh->src_len;
	rule6->dst.plen = frh->dst_len;
	rule6->tclass = frh->tos;

	err = 0;
errout:
	return err;
}

static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
			     struct nlattr **tb)
{
	struct fib6_rule *rule6 = (struct fib6_rule *) rule;

	if (frh->src_len && (rule6->src.plen != frh->src_len))
		return 0;

	if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
		return 0;

	if (frh->tos && (rule6->tclass != frh->tos))
		return 0;

	if (frh->src_len &&
	    nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
		return 0;

	if (frh->dst_len &&
	    nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
		return 0;

	return 1;
}

static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
			  struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
{
	struct fib6_rule *rule6 = (struct fib6_rule *) rule;

	frh->family = AF_INET6;
	frh->dst_len = rule6->dst.plen;
	frh->src_len = rule6->src.plen;
	frh->tos = rule6->tclass;

	if (rule6->dst.plen)
		NLA_PUT(skb, FRA_DST, sizeof(struct in6_addr),
			&rule6->dst.addr);

	if (rule6->src.plen)
		NLA_PUT(skb, FRA_SRC, sizeof(struct in6_addr),
			&rule6->src.addr);

	return 0;

nla_put_failure:
	return -ENOBUFS;
}

static u32 fib6_rule_default_pref(struct fib_rules_ops *ops)
{
	return 0x3FFF;
}

static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
{
	return nla_total_size(16) /* dst */
	       + nla_total_size(16); /* src */
}

static struct fib_rules_ops fib6_rules_ops_template = {
	.family			= AF_INET6,
	.rule_size		= sizeof(struct fib6_rule),
	.addr_size		= sizeof(struct in6_addr),
	.action			= fib6_rule_action,
	.match			= fib6_rule_match,
	.configure		= fib6_rule_configure,
	.compare		= fib6_rule_compare,
	.fill			= fib6_rule_fill,
	.default_pref		= fib6_rule_default_pref,
	.nlmsg_payload		= fib6_rule_nlmsg_payload,
	.nlgroup		= RTNLGRP_IPV6_RULE,
	.policy			= fib6_rule_policy,
	.owner			= THIS_MODULE,
	.fro_net		= &init_net,
};

static int __init fib6_default_rules_init(void)
{
	int err;

	fib6_rules_ops = kmemdup(&fib6_rules_ops_template,
				 sizeof(*fib6_rules_ops), GFP_KERNEL);
	if (!fib6_rules_ops)
		return -ENOMEM;

	INIT_LIST_HEAD(&fib6_rules_ops->rules_list);

	err = fib_default_rule_add(fib6_rules_ops, 0,
				   RT6_TABLE_LOCAL, FIB_RULE_PERMANENT);
	if (err < 0)
		return err;
	err = fib_default_rule_add(fib6_rules_ops, 0x7FFE, RT6_TABLE_MAIN, 0);
	if (err < 0)
		return err;
	return 0;
}

int __init fib6_rules_init(void)
{
	int ret;

	ret = fib6_default_rules_init();
	if (ret)
		goto out;

	ret = fib_rules_register(fib6_rules_ops);
	if (ret)
		goto out_default_rules_init;
out:
	return ret;

out_default_rules_init:
	fib_rules_cleanup_ops(fib6_rules_ops);
	kfree(fib6_rules_ops);
	goto out;
}

void fib6_rules_cleanup(void)
{
	fib_rules_unregister(fib6_rules_ops);
	kfree(fib6_rules_ops);
}
Commit	Line	Data
101367c2 TG	1	/*
	2	* net/ipv6/fib6_rules.c IPv6 Routing Policy Rules
	3	*
	4	* Copyright (C)2003-2006 Helsinki University of Technology
	5	* Copyright (C)2003-2006 USAGI/WIDE Project
	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License as
	9	* published by the Free Software Foundation, version 2.
	10	*
	11	* Authors
	12	* Thomas Graf <tgraf@suug.ch>
	13	* Ville Nuorvala <vnuorval@tcs.hut.fi>
	14	*/
	15
101367c2 TG	16	#include <linux/netdevice.h>
	17
	18	#include <net/fib_rules.h>
	19	#include <net/ipv6.h>
29f6af77	20	#include <net/addrconf.h>
101367c2 TG	21	#include <net/ip6_route.h>
	22	#include <net/netlink.h>
	23
	24	struct fib6_rule
	25	{
	26	struct fib_rule common;
	27	struct rt6key src;
	28	struct rt6key dst;
	29	u8 tclass;
	30	};
	31
eb5564b8	32	static struct fib_rules_ops *fib6_rules_ops;
101367c2	33
58f09b78 DL	34	struct dst_entry fib6_rule_lookup(struct net net, struct flowi *fl,
58f09b78 DL	35	int flags, pol_lookup_t lookup)
101367c2 TG	36	{
	37	struct fib_lookup_arg arg = {
	38	.lookup_ptr = lookup,
	39	};
	40
eb5564b8	41	fib_rules_lookup(fib6_rules_ops, fl, flags, &arg);
101367c2 TG	42	if (arg.rule)
	43	fib_rule_put(arg.rule);
	44
b1429553	45	if (arg.result)
40aa7b90	46	return arg.result;
b1429553 VN	47
	48	dst_hold(&ip6_null_entry.u.dst);
	49	return &ip6_null_entry.u.dst;
101367c2 TG	50	}
101367c2 TG	51
8ce11e6a AB	52	static int fib6_rule_action(struct fib_rule rule, struct flowi flp,
8ce11e6a AB	53	int flags, struct fib_lookup_arg *arg)
101367c2 TG	54	{
	55	struct rt6_info *rt = NULL;
	56	struct fib6_table *table;
	57	pol_lookup_t lookup = arg->lookup_ptr;
	58
	59	switch (rule->action) {
	60	case FR_ACT_TO_TBL:
	61	break;
	62	case FR_ACT_UNREACHABLE:
	63	rt = &ip6_null_entry;
	64	goto discard_pkt;
	65	default:
	66	case FR_ACT_BLACKHOLE:
	67	rt = &ip6_blk_hole_entry;
	68	goto discard_pkt;
	69	case FR_ACT_PROHIBIT:
	70	rt = &ip6_prohibit_entry;
	71	goto discard_pkt;
	72	}
	73
58f09b78	74	table = fib6_get_table(&init_net, rule->table);
101367c2 TG	75	if (table)
	76	rt = lookup(table, flp, flags);
	77
29f6af77 YH	78	if (rt != &ip6_null_entry) {
	79	struct fib6_rule r = (struct fib6_rule )rule;
	80
	81	/*
	82	* If we need to find a source address for this traffic,
	83	* we check the result if it meets requirement of the rule.
	84	*/
	85	if ((rule->flags & FIB_RULE_FIND_SADDR) &&
	86	r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
	87	struct in6_addr saddr;
5e5f3f0f YH	88	if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev,
5e5f3f0f YH	89	&flp->fl6_dst, &saddr))
29f6af77 YH	90	goto again;
	91	if (!ipv6_prefix_equal(&saddr, &r->src.addr,
	92	r->src.plen))
	93	goto again;
	94	ipv6_addr_copy(&flp->fl6_src, &saddr);
	95	}
101367c2	96	goto out;
29f6af77 YH	97	}
29f6af77 YH	98	again:
101367c2	99	dst_release(&rt->u.dst);
3226f688 PM	100	rt = NULL;
	101	goto out;
	102
101367c2 TG	103	discard_pkt:
	104	dst_hold(&rt->u.dst);
	105	out:
	106	arg->result = rt;
	107	return rt == NULL ? -EAGAIN : 0;
	108	}
	109
	110
	111	static int fib6_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	112	{
	113	struct fib6_rule r = (struct fib6_rule ) rule;
	114
adaa70bb TG	115	if (r->dst.plen &&
adaa70bb TG	116	!ipv6_prefix_equal(&fl->fl6_dst, &r->dst.addr, r->dst.plen))
101367c2 TG	117	return 0;
101367c2 TG	118
29f6af77 YH	119	/*
	120	* If FIB_RULE_FIND_SADDR is set and we do not have a
	121	* source address for the traffic, we defer check for
	122	* source address.
	123	*/
adaa70bb	124	if (r->src.plen) {
29f6af77 YH	125	if (flags & RT6_LOOKUP_F_HAS_SADDR) {
	126	if (!ipv6_prefix_equal(&fl->fl6_src, &r->src.addr,
	127	r->src.plen))
	128	return 0;
	129	} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
adaa70bb TG	130	return 0;
adaa70bb TG	131	}
101367c2	132
2cc67cc7 YH	133	if (r->tclass && r->tclass != ((ntohl(fl->fl6_flowlabel) >> 20) & 0xff))
	134	return 0;
	135
101367c2 TG	136	return 1;
	137	}
	138
ef7c79ed	139	static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
1f6c9557	140	FRA_GENERIC_POLICY,
101367c2 TG	141	};
	142
	143	static int fib6_rule_configure(struct fib_rule rule, struct sk_buff skb,
	144	struct nlmsghdr nlh, struct fib_rule_hdr frh,
	145	struct nlattr **tb)
	146	{
	147	int err = -EINVAL;
	148	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	149
101367c2 TG	150	if (rule->action == FR_ACT_TO_TBL) {
	151	if (rule->table == RT6_TABLE_UNSPEC)
	152	goto errout;
	153
58f09b78	154	if (fib6_new_table(&init_net, rule->table) == NULL) {
101367c2 TG	155	err = -ENOBUFS;
	156	goto errout;
	157	}
	158	}
	159
e1701c68	160	if (frh->src_len)
101367c2 TG	161	nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
	162	sizeof(struct in6_addr));
	163
e1701c68	164	if (frh->dst_len)
101367c2 TG	165	nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
	166	sizeof(struct in6_addr));
	167
	168	rule6->src.plen = frh->src_len;
	169	rule6->dst.plen = frh->dst_len;
	170	rule6->tclass = frh->tos;
	171
	172	err = 0;
	173	errout:
	174	return err;
	175	}
	176
	177	static int fib6_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
	178	struct nlattr **tb)
	179	{
	180	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	181
	182	if (frh->src_len && (rule6->src.plen != frh->src_len))
	183	return 0;
	184
	185	if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
	186	return 0;
	187
	188	if (frh->tos && (rule6->tclass != frh->tos))
	189	return 0;
	190
e1701c68	191	if (frh->src_len &&
101367c2 TG	192	nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
	193	return 0;
	194
e1701c68	195	if (frh->dst_len &&
101367c2 TG	196	nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
	197	return 0;
	198
	199	return 1;
	200	}
	201
	202	static int fib6_rule_fill(struct fib_rule rule, struct sk_buff skb,
	203	struct nlmsghdr nlh, struct fib_rule_hdr frh)
	204	{
	205	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	206
	207	frh->family = AF_INET6;
	208	frh->dst_len = rule6->dst.plen;
	209	frh->src_len = rule6->src.plen;
	210	frh->tos = rule6->tclass;
	211
	212	if (rule6->dst.plen)
	213	NLA_PUT(skb, FRA_DST, sizeof(struct in6_addr),
	214	&rule6->dst.addr);
	215
	216	if (rule6->src.plen)
	217	NLA_PUT(skb, FRA_SRC, sizeof(struct in6_addr),
	218	&rule6->src.addr);
	219
	220	return 0;
	221
	222	nla_put_failure:
	223	return -ENOBUFS;
	224	}
	225
868d13ac	226	static u32 fib6_rule_default_pref(struct fib_rules_ops *ops)
101367c2 TG	227	{
	228	return 0x3FFF;
	229	}
	230
339bf98f TG	231	static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
	232	{
	233	return nla_total_size(16) /* dst */
	234	+ nla_total_size(16); /* src */
	235	}
	236
eb5564b8	237	static struct fib_rules_ops fib6_rules_ops_template = {
101367c2 TG	238	.family = AF_INET6,
101367c2 TG	239	.rule_size = sizeof(struct fib6_rule),
e1701c68	240	.addr_size = sizeof(struct in6_addr),
101367c2 TG	241	.action = fib6_rule_action,
	242	.match = fib6_rule_match,
	243	.configure = fib6_rule_configure,
	244	.compare = fib6_rule_compare,
	245	.fill = fib6_rule_fill,
	246	.default_pref = fib6_rule_default_pref,
339bf98f	247	.nlmsg_payload = fib6_rule_nlmsg_payload,
101367c2 TG	248	.nlgroup = RTNLGRP_IPV6_RULE,
101367c2 TG	249	.policy = fib6_rule_policy,
101367c2	250	.owner = THIS_MODULE,
03592383	251	.fro_net = &init_net,
101367c2 TG	252	};
101367c2 TG	253
2994c638	254	static int __init fib6_default_rules_init(void)
101367c2	255	{
2994c638 DL	256	int err;
2994c638 DL	257
eb5564b8 DL	258	fib6_rules_ops = kmemdup(&fib6_rules_ops_template,
	259	sizeof(*fib6_rules_ops), GFP_KERNEL);
	260	if (!fib6_rules_ops)
	261	return -ENOMEM;
	262
	263	INIT_LIST_HEAD(&fib6_rules_ops->rules_list);
	264
	265	err = fib_default_rule_add(fib6_rules_ops, 0,
2994c638 DL	266	RT6_TABLE_LOCAL, FIB_RULE_PERMANENT);
	267	if (err < 0)
	268	return err;
eb5564b8	269	err = fib_default_rule_add(fib6_rules_ops, 0x7FFE, RT6_TABLE_MAIN, 0);
2994c638 DL	270	if (err < 0)
	271	return err;
	272	return 0;
	273	}
101367c2	274
9eb87f3f	275	int __init fib6_rules_init(void)
2994c638	276	{
9eb87f3f DL	277	int ret;
	278
	279	ret = fib6_default_rules_init();
	280	if (ret)
	281	goto out;
	282
eb5564b8	283	ret = fib_rules_register(fib6_rules_ops);
9eb87f3f DL	284	if (ret)
	285	goto out_default_rules_init;
	286	out:
	287	return ret;
	288
	289	out_default_rules_init:
eb5564b8 DL	290	fib_rules_cleanup_ops(fib6_rules_ops);
eb5564b8 DL	291	kfree(fib6_rules_ops);
9eb87f3f	292	goto out;
101367c2 TG	293	}
	294
	295	void fib6_rules_cleanup(void)
	296	{
eb5564b8 DL	297	fib_rules_unregister(fib6_rules_ops);
eb5564b8 DL	298	kfree(fib6_rules_ops);
101367c2	299	}