[linux-2.6-block.git] / net / ipv6 / fib6_rules.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * net/ipv6/fib6_rules.c	IPv6 Routing Policy Rules
 *
 * Copyright (C)2003-2006 Helsinki University of Technology
 * Copyright (C)2003-2006 USAGI/WIDE Project
 *
 * Authors
 *	Thomas Graf		<tgraf@suug.ch>
 *	Ville Nuorvala		<vnuorval@tcs.hut.fi>
 */

#include <linux/netdevice.h>
#include <linux/notifier.h>
#include <linux/export.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 bool fib6_rule_matchall(const struct fib_rule *rule)
{
	struct fib6_rule *r = container_of(rule, struct fib6_rule, common);

	if (r->dst.plen || r->src.plen || r->tclass)
		return false;
	return fib_rule_matchall(rule);
}

bool fib6_rule_default(const struct fib_rule *rule)
{
	if (!fib6_rule_matchall(rule) || rule->action != FR_ACT_TO_TBL ||
	    rule->l3mdev)
		return false;
	if (rule->table != RT6_TABLE_LOCAL && rule->table != RT6_TABLE_MAIN)
		return false;
	return true;
}
EXPORT_SYMBOL_GPL(fib6_rule_default);

int fib6_rules_dump(struct net *net, struct notifier_block *nb)
{
	return fib_rules_dump(net, nb, AF_INET6);
}

unsigned int fib6_rules_seq_read(struct net *net)
{
	return fib_rules_seq_read(net, AF_INET6);
}

/* called with rcu lock held; no reference taken on fib6_info */
int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
		struct fib6_result *res, int flags)
{
	int err;

	if (net->ipv6.fib6_has_custom_rules) {
		struct fib_lookup_arg arg = {
			.lookup_ptr = fib6_table_lookup,
			.lookup_data = &oif,
			.result = res,
			.flags = FIB_LOOKUP_NOREF,
		};

		l3mdev_update_flow(net, flowi6_to_flowi(fl6));

		err = fib_rules_lookup(net->ipv6.fib6_rules_ops,
				       flowi6_to_flowi(fl6), flags, &arg);
	} else {
		err = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, oif,
					fl6, res, flags);
		if (err || res->f6i == net->ipv6.fib6_null_entry)
			err = fib6_table_lookup(net, net->ipv6.fib6_main_tbl,
						oif, fl6, res, flags);
	}

	return err;
}

struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
				   const struct sk_buff *skb,
				   int flags, pol_lookup_t lookup)
{
	if (net->ipv6.fib6_has_custom_rules) {
		struct fib6_result res = {};
		struct fib_lookup_arg arg = {
			.lookup_ptr = lookup,
			.lookup_data = skb,
			.result = &res,
			.flags = FIB_LOOKUP_NOREF,
		};

		/* update flow if oif or iif point to device enslaved to l3mdev */
		l3mdev_update_flow(net, flowi6_to_flowi(fl6));

		fib_rules_lookup(net->ipv6.fib6_rules_ops,
				 flowi6_to_flowi(fl6), flags, &arg);

		if (res.rt6)
			return &res.rt6->dst;
	} else {
		struct rt6_info *rt;

		rt = lookup(net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
		if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
			return &rt->dst;
		ip6_rt_put_flags(rt, flags);
		rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
		if (rt->dst.error != -EAGAIN)
			return &rt->dst;
		ip6_rt_put_flags(rt, flags);
	}

	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
		dst_hold(&net->ipv6.ip6_null_entry->dst);
	return &net->ipv6.ip6_null_entry->dst;
}

static int fib6_rule_saddr(struct net *net, struct fib_rule *rule, int flags,
			   struct flowi6 *flp6, const struct net_device *dev)
{
	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(net, dev, &flp6->daddr,
				       rt6_flags2srcprefs(flags), &saddr))
			return -EAGAIN;

		if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
			return -EAGAIN;

		flp6->saddr = saddr;
	}

	return 0;
}

static int fib6_rule_action_alt(struct fib_rule *rule, struct flowi *flp,
				int flags, struct fib_lookup_arg *arg)
{
	struct fib6_result *res = arg->result;
	struct flowi6 *flp6 = &flp->u.ip6;
	struct net *net = rule->fr_net;
	struct fib6_table *table;
	int err, *oif;
	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;
	}

	tb_id = fib_rule_get_table(rule, arg);
	table = fib6_get_table(net, tb_id);
	if (!table)
		return -EAGAIN;

	oif = (int *)arg->lookup_data;
	err = fib6_table_lookup(net, table, *oif, flp6, res, flags);
	if (!err && res->f6i != net->ipv6.fib6_null_entry)
		err = fib6_rule_saddr(net, rule, flags, flp6,
				      res->nh->fib_nh_dev);
	else
		err = -EAGAIN;

	return err;
}

static int __fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
			      int flags, struct fib_lookup_arg *arg)
{
	struct fib6_result *res = arg->result;
	struct flowi6 *flp6 = &flp->u.ip6;
	struct rt6_info *rt = NULL;
	struct fib6_table *table;
	struct net *net = rule->fr_net;
	pol_lookup_t lookup = arg->lookup_ptr;
	int err = 0;
	u32 tb_id;

	switch (rule->action) {
	case FR_ACT_TO_TBL:
		break;
	case FR_ACT_UNREACHABLE:
		err = -ENETUNREACH;
		rt = net->ipv6.ip6_null_entry;
		goto discard_pkt;
	default:
	case FR_ACT_BLACKHOLE:
		err = -EINVAL;
		rt = net->ipv6.ip6_blk_hole_entry;
		goto discard_pkt;
	case FR_ACT_PROHIBIT:
		err = -EACCES;
		rt = net->ipv6.ip6_prohibit_entry;
		goto discard_pkt;
	}

	tb_id = fib_rule_get_table(rule, arg);
	table = fib6_get_table(net, tb_id);
	if (!table) {
		err = -EAGAIN;
		goto out;
	}

	rt = lookup(net, table, flp6, arg->lookup_data, flags);
	if (rt != net->ipv6.ip6_null_entry) {
		err = fib6_rule_saddr(net, rule, flags, flp6,
				      ip6_dst_idev(&rt->dst)->dev);

		if (err == -EAGAIN)
			goto again;

		err = rt->dst.error;
		if (err != -EAGAIN)
			goto out;
	}
again:
	ip6_rt_put_flags(rt, flags);
	err = -EAGAIN;
	rt = NULL;
	goto out;

discard_pkt:
	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
		dst_hold(&rt->dst);
out:
	res->rt6 = rt;
	return err;
}

static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
			    int flags, struct fib_lookup_arg *arg)
{
	if (arg->lookup_ptr == fib6_table_lookup)
		return fib6_rule_action_alt(rule, flp, flags, arg);

	return __fib6_rule_action(rule, flp, flags, arg);
}

static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
{
	struct fib6_result *res = arg->result;
	struct rt6_info *rt = res->rt6;
	struct net_device *dev = NULL;

	if (!rt)
		return false;

	if (rt->rt6i_idev)
		dev = rt->rt6i_idev->dev;

	/* do not accept result if the route does
	 * not meet the required prefix length
	 */
	if (rt->rt6i_dst.plen <= 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:
	ip6_rt_put(rt);
	return true;
}

static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
{
	struct fib6_rule *r = (struct fib6_rule *) rule;
	struct flowi6 *fl6 = &fl->u.ip6;

	if (r->dst.plen &&
	    !ipv6_prefix_equal(&fl6->daddr, &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(&fl6->saddr, &r->src.addr,
					       r->src.plen))
				return 0;
		} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
			return 0;
	}

	if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel))
		return 0;

	if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
		return 0;

	if (fib_rule_port_range_set(&rule->sport_range) &&
	    !fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport))
		return 0;

	if (fib_rule_port_range_set(&rule->dport_range) &&
	    !fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport))
		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 fib_rule_hdr *frh,
			       struct nlattr **tb,
			       struct netlink_ext_ack *extack)
{
	int err = -EINVAL;
	struct net *net = sock_net(skb->sk);
	struct fib6_rule *rule6 = (struct fib6_rule *) rule;

	if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
		if (rule->table == RT6_TABLE_UNSPEC) {
			NL_SET_ERR_MSG(extack, "Invalid table");
			goto errout;
		}

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

	if (frh->src_len)
		rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);

	if (frh->dst_len)
		rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);

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

	if (fib_rule_requires_fldissect(rule))
		net->ipv6.fib6_rules_require_fldissect++;

	net->ipv6.fib6_has_custom_rules = true;
	err = 0;
errout:
	return err;
}

static int fib6_rule_delete(struct fib_rule *rule)
{
	struct net *net = rule->fr_net;

	if (net->ipv6.fib6_rules_require_fldissect &&
	    fib_rule_requires_fldissect(rule))
		net->ipv6.fib6_rules_require_fldissect--;

	return 0;
}

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 fib_rule_hdr *frh)
{
	struct fib6_rule *rule6 = (struct fib6_rule *) rule;

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

	if ((rule6->dst.plen &&
	     nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) ||
	    (rule6->src.plen &&
	     nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -ENOBUFS;
}

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

static const struct fib_rules_ops __net_initconst 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,
	.suppress		= fib6_rule_suppress,
	.configure		= fib6_rule_configure,
	.delete			= fib6_rule_delete,
	.compare		= fib6_rule_compare,
	.fill			= fib6_rule_fill,
	.nlmsg_payload		= fib6_rule_nlmsg_payload,
	.nlgroup		= RTNLGRP_IPV6_RULE,
	.policy			= fib6_rule_policy,
	.owner			= THIS_MODULE,
	.fro_net		= &init_net,
};

static int __net_init fib6_rules_net_init(struct net *net)
{
	struct fib_rules_ops *ops;
	int err = -ENOMEM;

	ops = fib_rules_register(&fib6_rules_ops_template, net);
	if (IS_ERR(ops))
		return PTR_ERR(ops);

	err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0);
	if (err)
		goto out_fib6_rules_ops;

	err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0);
	if (err)
		goto out_fib6_rules_ops;

	net->ipv6.fib6_rules_ops = ops;
	net->ipv6.fib6_rules_require_fldissect = 0;
out:
	return err;

out_fib6_rules_ops:
	fib_rules_unregister(ops);
	goto out;
}

static void __net_exit fib6_rules_net_exit(struct net *net)
{
	rtnl_lock();
	fib_rules_unregister(net->ipv6.fib6_rules_ops);
	rtnl_unlock();
}

static struct pernet_operations fib6_rules_net_ops = {
	.init = fib6_rules_net_init,
	.exit = fib6_rules_net_exit,
};

int __init fib6_rules_init(void)
{
	return register_pernet_subsys(&fib6_rules_net_ops);
}


void fib6_rules_cleanup(void)
{
	unregister_pernet_subsys(&fib6_rules_net_ops);
}
Commit	Line	Data
a10e763b	1	// SPDX-License-Identifier: GPL-2.0-only
101367c2 TG	2	/*
	3	* net/ipv6/fib6_rules.c IPv6 Routing Policy Rules
	4	*
	5	* Copyright (C)2003-2006 Helsinki University of Technology
	6	* Copyright (C)2003-2006 USAGI/WIDE Project
	7	*
101367c2 TG	8	* Authors
	9	* Thomas Graf <tgraf@suug.ch>
	10	* Ville Nuorvala <vnuorval@tcs.hut.fi>
	11	*/
	12
101367c2	13	#include <linux/netdevice.h>
dcb18f76	14	#include <linux/notifier.h>
bc3b2d7f	15	#include <linux/export.h>
101367c2 TG	16
	17	#include <net/fib_rules.h>
	18	#include <net/ipv6.h>
29f6af77	19	#include <net/addrconf.h>
101367c2 TG	20	#include <net/ip6_route.h>
	21	#include <net/netlink.h>
	22
911c8541	23	struct fib6_rule {
101367c2 TG	24	struct fib_rule common;
	25	struct rt6key src;
	26	struct rt6key dst;
	27	u8 tclass;
	28	};
	29
e3ea9731 IS	30	static bool fib6_rule_matchall(const struct fib_rule *rule)
	31	{
	32	struct fib6_rule *r = container_of(rule, struct fib6_rule, common);
	33
	34	if (r->dst.plen \|\| r->src.plen \|\| r->tclass)
	35	return false;
	36	return fib_rule_matchall(rule);
	37	}
	38
	39	bool fib6_rule_default(const struct fib_rule *rule)
	40	{
	41	if (!fib6_rule_matchall(rule) \|\| rule->action != FR_ACT_TO_TBL \|\|
	42	rule->l3mdev)
	43	return false;
	44	if (rule->table != RT6_TABLE_LOCAL && rule->table != RT6_TABLE_MAIN)
	45	return false;
	46	return true;
	47	}
	48	EXPORT_SYMBOL_GPL(fib6_rule_default);
	49
dcb18f76 IS	50	int fib6_rules_dump(struct net net, struct notifier_block nb)
	51	{
	52	return fib_rules_dump(net, nb, AF_INET6);
	53	}
	54
	55	unsigned int fib6_rules_seq_read(struct net *net)
	56	{
	57	return fib_rules_seq_read(net, AF_INET6);
	58	}
	59
138118ec	60	/* called with rcu lock held; no reference taken on fib6_info */
effda4dd DA	61	int fib6_lookup(struct net net, int oif, struct flowi6 fl6,
effda4dd DA	62	struct fib6_result *res, int flags)
138118ec	63	{
138118ec DA	64	int err;
	65
	66	if (net->ipv6.fib6_has_custom_rules) {
	67	struct fib_lookup_arg arg = {
	68	.lookup_ptr = fib6_table_lookup,
	69	.lookup_data = &oif,
effda4dd	70	.result = res,
138118ec DA	71	.flags = FIB_LOOKUP_NOREF,
	72	};
	73
	74	l3mdev_update_flow(net, flowi6_to_flowi(fl6));
	75
	76	err = fib_rules_lookup(net->ipv6.fib6_rules_ops,
	77	flowi6_to_flowi(fl6), flags, &arg);
138118ec	78	} else {
effda4dd DA	79	err = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, oif,
	80	fl6, res, flags);
	81	if (err \|\| res->f6i == net->ipv6.fib6_null_entry)
	82	err = fib6_table_lookup(net, net->ipv6.fib6_main_tbl,
	83	oif, fl6, res, flags);
138118ec DA	84	}
138118ec DA	85
effda4dd	86	return err;
138118ec DA	87	}
138118ec DA	88
4c9483b2	89	struct dst_entry fib6_rule_lookup(struct net net, struct flowi6 *fl6,
b75cc8f9	90	const struct sk_buff *skb,
58f09b78	91	int flags, pol_lookup_t lookup)
101367c2	92	{
feca7d8c	93	if (net->ipv6.fib6_has_custom_rules) {
a65120ba	94	struct fib6_result res = {};
feca7d8c VB	95	struct fib_lookup_arg arg = {
feca7d8c VB	96	.lookup_ptr = lookup,
b75cc8f9	97	.lookup_data = skb,
a65120ba	98	.result = &res,
feca7d8c VB	99	.flags = FIB_LOOKUP_NOREF,
	100	};
	101
	102	/* update flow if oif or iif point to device enslaved to l3mdev */
	103	l3mdev_update_flow(net, flowi6_to_flowi(fl6));
	104
	105	fib_rules_lookup(net->ipv6.fib6_rules_ops,
	106	flowi6_to_flowi(fl6), flags, &arg);
	107
a65120ba DA	108	if (res.rt6)
a65120ba DA	109	return &res.rt6->dst;
feca7d8c VB	110	} else {
	111	struct rt6_info *rt;
	112
b75cc8f9	113	rt = lookup(net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
feca7d8c VB	114	if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
feca7d8c VB	115	return &rt->dst;
d64a1f57	116	ip6_rt_put_flags(rt, flags);
b75cc8f9	117	rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
feca7d8c VB	118	if (rt->dst.error != -EAGAIN)
feca7d8c VB	119	return &rt->dst;
d64a1f57	120	ip6_rt_put_flags(rt, flags);
feca7d8c	121	}
b1429553	122
d64a1f57 WW	123	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
d64a1f57 WW	124	dst_hold(&net->ipv6.ip6_null_entry->dst);
07f61557	125	return &net->ipv6.ip6_null_entry->dst;
101367c2 TG	126	}
101367c2 TG	127
cc065a9e DA	128	static int fib6_rule_saddr(struct net net, struct fib_rule rule, int flags,
	129	struct flowi6 flp6, const struct net_device dev)
	130	{
	131	struct fib6_rule r = (struct fib6_rule )rule;
	132
	133	/* If we need to find a source address for this traffic,
	134	* we check the result if it meets requirement of the rule.
	135	*/
	136	if ((rule->flags & FIB_RULE_FIND_SADDR) &&
	137	r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
	138	struct in6_addr saddr;
	139
	140	if (ipv6_dev_get_saddr(net, dev, &flp6->daddr,
	141	rt6_flags2srcprefs(flags), &saddr))
	142	return -EAGAIN;
	143
	144	if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
	145	return -EAGAIN;
	146
	147	flp6->saddr = saddr;
	148	}
	149
	150	return 0;
	151	}
	152
138118ec DA	153	static int fib6_rule_action_alt(struct fib_rule rule, struct flowi flp,
	154	int flags, struct fib_lookup_arg *arg)
	155	{
effda4dd	156	struct fib6_result *res = arg->result;
138118ec DA	157	struct flowi6 *flp6 = &flp->u.ip6;
	158	struct net *net = rule->fr_net;
	159	struct fib6_table *table;
b2f97f7d	160	int err, *oif;
138118ec DA	161	u32 tb_id;
	162
	163	switch (rule->action) {
	164	case FR_ACT_TO_TBL:
	165	break;
	166	case FR_ACT_UNREACHABLE:
	167	return -ENETUNREACH;
	168	case FR_ACT_PROHIBIT:
	169	return -EACCES;
	170	case FR_ACT_BLACKHOLE:
	171	default:
	172	return -EINVAL;
	173	}
	174
	175	tb_id = fib_rule_get_table(rule, arg);
	176	table = fib6_get_table(net, tb_id);
	177	if (!table)
	178	return -EAGAIN;
	179
	180	oif = (int *)arg->lookup_data;
effda4dd DA	181	err = fib6_table_lookup(net, table, *oif, flp6, res, flags);
effda4dd DA	182	if (!err && res->f6i != net->ipv6.fib6_null_entry)
138118ec	183	err = fib6_rule_saddr(net, rule, flags, flp6,
effda4dd	184	res->nh->fib_nh_dev);
b2f97f7d DA	185	else
b2f97f7d DA	186	err = -EAGAIN;
138118ec DA	187
	188	return err;
	189	}
	190
	191	static int __fib6_rule_action(struct fib_rule rule, struct flowi flp,
	192	int flags, struct fib_lookup_arg *arg)
101367c2	193	{
a65120ba	194	struct fib6_result *res = arg->result;
4c9483b2	195	struct flowi6 *flp6 = &flp->u.ip6;
101367c2 TG	196	struct rt6_info *rt = NULL;
101367c2 TG	197	struct fib6_table *table;
8ed67789	198	struct net *net = rule->fr_net;
101367c2	199	pol_lookup_t lookup = arg->lookup_ptr;
46b3a421	200	int err = 0;
96c63fa7	201	u32 tb_id;
101367c2 TG	202
	203	switch (rule->action) {
	204	case FR_ACT_TO_TBL:
	205	break;
	206	case FR_ACT_UNREACHABLE:
46b3a421	207	err = -ENETUNREACH;
8ed67789	208	rt = net->ipv6.ip6_null_entry;
101367c2 TG	209	goto discard_pkt;
	210	default:
	211	case FR_ACT_BLACKHOLE:
46b3a421	212	err = -EINVAL;
8ed67789	213	rt = net->ipv6.ip6_blk_hole_entry;
101367c2 TG	214	goto discard_pkt;
101367c2 TG	215	case FR_ACT_PROHIBIT:
46b3a421	216	err = -EACCES;
8ed67789	217	rt = net->ipv6.ip6_prohibit_entry;
101367c2 TG	218	goto discard_pkt;
	219	}
	220
96c63fa7 DA	221	tb_id = fib_rule_get_table(rule, arg);
96c63fa7 DA	222	table = fib6_get_table(net, tb_id);
46b3a421 HFS	223	if (!table) {
	224	err = -EAGAIN;
	225	goto out;
	226	}
101367c2	227
b75cc8f9	228	rt = lookup(net, table, flp6, arg->lookup_data, flags);
8ed67789	229	if (rt != net->ipv6.ip6_null_entry) {
cc065a9e DA	230	err = fib6_rule_saddr(net, rule, flags, flp6,
	231	ip6_dst_idev(&rt->dst)->dev);
	232
	233	if (err == -EAGAIN)
	234	goto again;
	235
73ba57bf	236	err = rt->dst.error;
07f61557 SP	237	if (err != -EAGAIN)
07f61557 SP	238	goto out;
29f6af77 YH	239	}
29f6af77 YH	240	again:
d64a1f57	241	ip6_rt_put_flags(rt, flags);
46b3a421	242	err = -EAGAIN;
3226f688 PM	243	rt = NULL;
	244	goto out;
	245
101367c2	246	discard_pkt:
d64a1f57 WW	247	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
d64a1f57 WW	248	dst_hold(&rt->dst);
101367c2	249	out:
a65120ba	250	res->rt6 = rt;
46b3a421	251	return err;
101367c2 TG	252	}
101367c2 TG	253
138118ec DA	254	static int fib6_rule_action(struct fib_rule rule, struct flowi flp,
	255	int flags, struct fib_lookup_arg *arg)
	256	{
	257	if (arg->lookup_ptr == fib6_table_lookup)
	258	return fib6_rule_action_alt(rule, flp, flags, arg);
	259
	260	return __fib6_rule_action(rule, flp, flags, arg);
	261	}
	262
7764a45a ST	263	static bool fib6_rule_suppress(struct fib_rule rule, struct fib_lookup_arg arg)
7764a45a ST	264	{
a65120ba DA	265	struct fib6_result *res = arg->result;
a65120ba DA	266	struct rt6_info *rt = res->rt6;
673498b8 ST	267	struct net_device *dev = NULL;
673498b8 ST	268
a65120ba DA	269	if (!rt)
	270	return false;
	271
673498b8 ST	272	if (rt->rt6i_idev)
	273	dev = rt->rt6i_idev->dev;
	274
7764a45a ST	275	/* do not accept result if the route does
	276	* not meet the required prefix length
	277	*/
73f5698e	278	if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
6ef94cfa ST	279	goto suppress_route;
	280
	281	/* do not accept result if the route uses a device
	282	* belonging to a forbidden interface group
	283	*/
	284	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	285	goto suppress_route;
	286
	287	return false;
	288
	289	suppress_route:
04f0888d ST	290	ip6_rt_put(rt);
04f0888d ST	291	return true;
7764a45a	292	}
101367c2 TG	293
	294	static int fib6_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	295	{
	296	struct fib6_rule r = (struct fib6_rule ) rule;
4c9483b2	297	struct flowi6 *fl6 = &fl->u.ip6;
101367c2	298
adaa70bb	299	if (r->dst.plen &&
4c9483b2	300	!ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
101367c2 TG	301	return 0;
101367c2 TG	302
29f6af77 YH	303	/*
	304	* If FIB_RULE_FIND_SADDR is set and we do not have a
	305	* source address for the traffic, we defer check for
	306	* source address.
	307	*/
adaa70bb	308	if (r->src.plen) {
29f6af77	309	if (flags & RT6_LOOKUP_F_HAS_SADDR) {
4c9483b2	310	if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
29f6af77 YH	311	r->src.plen))
	312	return 0;
	313	} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
adaa70bb TG	314	return 0;
adaa70bb TG	315	}
101367c2	316
d76ed22b	317	if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel))
2cc67cc7 YH	318	return 0;
2cc67cc7 YH	319
bb0ad198 RP	320	if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
	321	return 0;
	322
	323	if (fib_rule_port_range_set(&rule->sport_range) &&
	324	!fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport))
	325	return 0;
	326
	327	if (fib_rule_port_range_set(&rule->dport_range) &&
	328	!fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport))
	329	return 0;
	330
101367c2 TG	331	return 1;
	332	}
	333
ef7c79ed	334	static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
1f6c9557	335	FRA_GENERIC_POLICY,
101367c2 TG	336	};
	337
	338	static int fib6_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	339	struct fib_rule_hdr *frh,
b16fb418 RP	340	struct nlattr **tb,
b16fb418 RP	341	struct netlink_ext_ack *extack)
101367c2 TG	342	{
101367c2 TG	343	int err = -EINVAL;
3b1e0a65	344	struct net *net = sock_net(skb->sk);
101367c2 TG	345	struct fib6_rule rule6 = (struct fib6_rule ) rule;
101367c2 TG	346
96c63fa7	347	if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
b16fb418 RP	348	if (rule->table == RT6_TABLE_UNSPEC) {
b16fb418 RP	349	NL_SET_ERR_MSG(extack, "Invalid table");
101367c2	350	goto errout;
b16fb418	351	}
101367c2	352
dcabb819	353	if (fib6_new_table(net, rule->table) == NULL) {
101367c2 TG	354	err = -ENOBUFS;
	355	goto errout;
	356	}
	357	}
	358
e1701c68	359	if (frh->src_len)
67b61f6c	360	rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
101367c2	361
e1701c68	362	if (frh->dst_len)
67b61f6c	363	rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
101367c2 TG	364
	365	rule6->src.plen = frh->src_len;
	366	rule6->dst.plen = frh->dst_len;
	367	rule6->tclass = frh->tos;
	368
5e5d6fed RP	369	if (fib_rule_requires_fldissect(rule))
	370	net->ipv6.fib6_rules_require_fldissect++;
	371
feca7d8c	372	net->ipv6.fib6_has_custom_rules = true;
101367c2 TG	373	err = 0;
	374	errout:
	375	return err;
	376	}
	377
5e5d6fed RP	378	static int fib6_rule_delete(struct fib_rule *rule)
	379	{
	380	struct net *net = rule->fr_net;
	381
	382	if (net->ipv6.fib6_rules_require_fldissect &&
	383	fib_rule_requires_fldissect(rule))
	384	net->ipv6.fib6_rules_require_fldissect--;
	385
	386	return 0;
	387	}
	388
101367c2 TG	389	static int fib6_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
	390	struct nlattr **tb)
	391	{
	392	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	393
	394	if (frh->src_len && (rule6->src.plen != frh->src_len))
	395	return 0;
	396
	397	if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
	398	return 0;
	399
	400	if (frh->tos && (rule6->tclass != frh->tos))
	401	return 0;
	402
e1701c68	403	if (frh->src_len &&
101367c2 TG	404	nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
	405	return 0;
	406
e1701c68	407	if (frh->dst_len &&
101367c2 TG	408	nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
	409	return 0;
	410
	411	return 1;
	412	}
	413
	414	static int fib6_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	415	struct fib_rule_hdr *frh)
101367c2 TG	416	{
	417	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	418
101367c2 TG	419	frh->dst_len = rule6->dst.plen;
	420	frh->src_len = rule6->src.plen;
	421	frh->tos = rule6->tclass;
	422
c78679e8	423	if ((rule6->dst.plen &&
930345ea	424	nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) \|\|
c78679e8	425	(rule6->src.plen &&
930345ea	426	nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
c78679e8	427	goto nla_put_failure;
101367c2 TG	428	return 0;
	429
	430	nla_put_failure:
	431	return -ENOBUFS;
	432	}
	433
339bf98f TG	434	static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
	435	{
	436	return nla_total_size(16) /* dst */
	437	+ nla_total_size(16); /* src */
	438	}
	439
04a6f82c	440	static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
25239cee	441	.family = AF_INET6,
101367c2	442	.rule_size = sizeof(struct fib6_rule),
e1701c68	443	.addr_size = sizeof(struct in6_addr),
101367c2 TG	444	.action = fib6_rule_action,
101367c2 TG	445	.match = fib6_rule_match,
7764a45a	446	.suppress = fib6_rule_suppress,
101367c2	447	.configure = fib6_rule_configure,
5e5d6fed	448	.delete = fib6_rule_delete,
101367c2 TG	449	.compare = fib6_rule_compare,
101367c2 TG	450	.fill = fib6_rule_fill,
339bf98f	451	.nlmsg_payload = fib6_rule_nlmsg_payload,
101367c2 TG	452	.nlgroup = RTNLGRP_IPV6_RULE,
101367c2 TG	453	.policy = fib6_rule_policy,
101367c2	454	.owner = THIS_MODULE,
03592383	455	.fro_net = &init_net,
101367c2 TG	456	};
101367c2 TG	457
2c8c1e72	458	static int __net_init fib6_rules_net_init(struct net *net)
101367c2	459	{
e9c5158a	460	struct fib_rules_ops *ops;
dcabb819	461	int err = -ENOMEM;
2994c638	462
e9c5158a EB	463	ops = fib_rules_register(&fib6_rules_ops_template, net);
	464	if (IS_ERR(ops))
	465	return PTR_ERR(ops);
eb5564b8	466
85b99092	467	err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0);
dcabb819 DL	468	if (err)
dcabb819 DL	469	goto out_fib6_rules_ops;
9eb87f3f	470
85b99092	471	err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0);
dcabb819	472	if (err)
e9c5158a	473	goto out_fib6_rules_ops;
9eb87f3f	474
85b99092	475	net->ipv6.fib6_rules_ops = ops;
5e5d6fed	476	net->ipv6.fib6_rules_require_fldissect = 0;
9eb87f3f	477	out:
dcabb819	478	return err;
9eb87f3f	479
dcabb819	480	out_fib6_rules_ops:
e9c5158a	481	fib_rules_unregister(ops);
9eb87f3f	482	goto out;
101367c2 TG	483	}
101367c2 TG	484
2c8c1e72	485	static void __net_exit fib6_rules_net_exit(struct net *net)
dcabb819	486	{
419df12f	487	rtnl_lock();
dcabb819	488	fib_rules_unregister(net->ipv6.fib6_rules_ops);
419df12f	489	rtnl_unlock();
dcabb819 DL	490	}
	491
	492	static struct pernet_operations fib6_rules_net_ops = {
	493	.init = fib6_rules_net_init,
	494	.exit = fib6_rules_net_exit,
	495	};
	496
	497	int __init fib6_rules_init(void)
	498	{
	499	return register_pernet_subsys(&fib6_rules_net_ops);
	500	}
	501
	502
101367c2 TG	503	void fib6_rules_cleanup(void)
101367c2 TG	504	{
ff4e1fb0	505	unregister_pernet_subsys(&fib6_rules_net_ops);
101367c2	506	}