[linux-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 <linux/indirect_call_wrapper.h>

#include <net/fib_rules.h>
#include <net/inet_dscp.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;
	dscp_t			dscp;
};

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->dscp)
		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,
		    struct netlink_ext_ack *extack)
{
	return fib_rules_dump(net, nb, AF_INET6, extack);
}

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 = pol_lookup_func(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 = pol_lookup_func(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 = pol_lookup_func(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;
}

INDIRECT_CALLABLE_SCOPE 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);
}

INDIRECT_CALLABLE_SCOPE bool fib6_rule_suppress(struct fib_rule *rule,
						int flags,
						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_flags(rt, flags);
	return true;
}

INDIRECT_CALLABLE_SCOPE 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->dscp && r->dscp != ip6_dscp(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 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 (!inet_validate_dscp(frh->tos)) {
		NL_SET_ERR_MSG(extack,
			       "Invalid dsfield (tos): ECN bits must be 0");
		goto errout;
	}
	rule6->dscp = inet_dsfield_to_dscp(frh->tos);

	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;

	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 && inet_dscp_to_dsfield(rule6->dscp) != 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 = inet_dscp_to_dsfield(rule6->dscp);

	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,
	.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;

	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_batch(struct list_head *net_list)
{
	struct net *net;

	rtnl_lock();
	list_for_each_entry(net, net_list, exit_list) {
		fib_rules_unregister(net->ipv6.fib6_rules_ops);
		cond_resched();
	}
	rtnl_unlock();
}

static struct pernet_operations fib6_rules_net_ops = {
	.init = fib6_rules_net_init,
	.exit_batch = fib6_rules_net_exit_batch,
};

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>
b9aaec8f	16	#include <linux/indirect_call_wrapper.h>
101367c2 TG	17
101367c2 TG	18	#include <net/fib_rules.h>
a410a0cf	19	#include <net/inet_dscp.h>
101367c2	20	#include <net/ipv6.h>
29f6af77	21	#include <net/addrconf.h>
101367c2 TG	22	#include <net/ip6_route.h>
	23	#include <net/netlink.h>
	24
911c8541	25	struct fib6_rule {
101367c2 TG	26	struct fib_rule common;
	27	struct rt6key src;
	28	struct rt6key dst;
a410a0cf	29	dscp_t dscp;
101367c2 TG	30	};
101367c2 TG	31
e3ea9731 IS	32	static bool fib6_rule_matchall(const struct fib_rule *rule)
	33	{
	34	struct fib6_rule *r = container_of(rule, struct fib6_rule, common);
	35
a410a0cf	36	if (r->dst.plen \|\| r->src.plen \|\| r->dscp)
e3ea9731 IS	37	return false;
	38	return fib_rule_matchall(rule);
	39	}
	40
	41	bool fib6_rule_default(const struct fib_rule *rule)
	42	{
	43	if (!fib6_rule_matchall(rule) \|\| rule->action != FR_ACT_TO_TBL \|\|
	44	rule->l3mdev)
	45	return false;
	46	if (rule->table != RT6_TABLE_LOCAL && rule->table != RT6_TABLE_MAIN)
	47	return false;
	48	return true;
	49	}
	50	EXPORT_SYMBOL_GPL(fib6_rule_default);
	51
b7a59557 JP	52	int fib6_rules_dump(struct net net, struct notifier_block nb,
b7a59557 JP	53	struct netlink_ext_ack *extack)
dcb18f76	54	{
b7a59557	55	return fib_rules_dump(net, nb, AF_INET6, extack);
dcb18f76 IS	56	}
	57
	58	unsigned int fib6_rules_seq_read(struct net *net)
	59	{
	60	return fib_rules_seq_read(net, AF_INET6);
	61	}
	62
138118ec	63	/* called with rcu lock held; no reference taken on fib6_info */
effda4dd DA	64	int fib6_lookup(struct net net, int oif, struct flowi6 fl6,
effda4dd DA	65	struct fib6_result *res, int flags)
138118ec	66	{
138118ec DA	67	int err;
	68
	69	if (net->ipv6.fib6_has_custom_rules) {
	70	struct fib_lookup_arg arg = {
	71	.lookup_ptr = fib6_table_lookup,
	72	.lookup_data = &oif,
effda4dd	73	.result = res,
138118ec DA	74	.flags = FIB_LOOKUP_NOREF,
	75	};
	76
	77	l3mdev_update_flow(net, flowi6_to_flowi(fl6));
	78
	79	err = fib_rules_lookup(net->ipv6.fib6_rules_ops,
	80	flowi6_to_flowi(fl6), flags, &arg);
138118ec	81	} else {
effda4dd DA	82	err = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, oif,
	83	fl6, res, flags);
	84	if (err \|\| res->f6i == net->ipv6.fib6_null_entry)
	85	err = fib6_table_lookup(net, net->ipv6.fib6_main_tbl,
	86	oif, fl6, res, flags);
138118ec DA	87	}
138118ec DA	88
effda4dd	89	return err;
138118ec DA	90	}
138118ec DA	91
4c9483b2	92	struct dst_entry fib6_rule_lookup(struct net net, struct flowi6 *fl6,
b75cc8f9	93	const struct sk_buff *skb,
58f09b78	94	int flags, pol_lookup_t lookup)
101367c2	95	{
feca7d8c	96	if (net->ipv6.fib6_has_custom_rules) {
a65120ba	97	struct fib6_result res = {};
feca7d8c VB	98	struct fib_lookup_arg arg = {
feca7d8c VB	99	.lookup_ptr = lookup,
b75cc8f9	100	.lookup_data = skb,
a65120ba	101	.result = &res,
feca7d8c VB	102	.flags = FIB_LOOKUP_NOREF,
	103	};
	104
	105	/* update flow if oif or iif point to device enslaved to l3mdev */
	106	l3mdev_update_flow(net, flowi6_to_flowi(fl6));
	107
	108	fib_rules_lookup(net->ipv6.fib6_rules_ops,
	109	flowi6_to_flowi(fl6), flags, &arg);
	110
a65120ba DA	111	if (res.rt6)
a65120ba DA	112	return &res.rt6->dst;
feca7d8c VB	113	} else {
	114	struct rt6_info *rt;
	115
55cced4f BV	116	rt = pol_lookup_func(lookup,
55cced4f BV	117	net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
feca7d8c VB	118	if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
feca7d8c VB	119	return &rt->dst;
d64a1f57	120	ip6_rt_put_flags(rt, flags);
55cced4f BV	121	rt = pol_lookup_func(lookup,
55cced4f BV	122	net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
feca7d8c VB	123	if (rt->dst.error != -EAGAIN)
feca7d8c VB	124	return &rt->dst;
d64a1f57	125	ip6_rt_put_flags(rt, flags);
feca7d8c	126	}
b1429553	127
d64a1f57 WW	128	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
d64a1f57 WW	129	dst_hold(&net->ipv6.ip6_null_entry->dst);
07f61557	130	return &net->ipv6.ip6_null_entry->dst;
101367c2 TG	131	}
101367c2 TG	132
cc065a9e DA	133	static int fib6_rule_saddr(struct net net, struct fib_rule rule, int flags,
	134	struct flowi6 flp6, const struct net_device dev)
	135	{
	136	struct fib6_rule r = (struct fib6_rule )rule;
	137
	138	/* If we need to find a source address for this traffic,
	139	* we check the result if it meets requirement of the rule.
	140	*/
	141	if ((rule->flags & FIB_RULE_FIND_SADDR) &&
	142	r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
	143	struct in6_addr saddr;
	144
	145	if (ipv6_dev_get_saddr(net, dev, &flp6->daddr,
	146	rt6_flags2srcprefs(flags), &saddr))
	147	return -EAGAIN;
	148
	149	if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
	150	return -EAGAIN;
	151
	152	flp6->saddr = saddr;
	153	}
	154
	155	return 0;
	156	}
	157
138118ec DA	158	static int fib6_rule_action_alt(struct fib_rule rule, struct flowi flp,
	159	int flags, struct fib_lookup_arg *arg)
	160	{
effda4dd	161	struct fib6_result *res = arg->result;
138118ec DA	162	struct flowi6 *flp6 = &flp->u.ip6;
	163	struct net *net = rule->fr_net;
	164	struct fib6_table *table;
b2f97f7d	165	int err, *oif;
138118ec DA	166	u32 tb_id;
	167
	168	switch (rule->action) {
	169	case FR_ACT_TO_TBL:
	170	break;
	171	case FR_ACT_UNREACHABLE:
	172	return -ENETUNREACH;
	173	case FR_ACT_PROHIBIT:
	174	return -EACCES;
	175	case FR_ACT_BLACKHOLE:
	176	default:
	177	return -EINVAL;
	178	}
	179
	180	tb_id = fib_rule_get_table(rule, arg);
	181	table = fib6_get_table(net, tb_id);
	182	if (!table)
	183	return -EAGAIN;
	184
	185	oif = (int *)arg->lookup_data;
effda4dd DA	186	err = fib6_table_lookup(net, table, *oif, flp6, res, flags);
effda4dd DA	187	if (!err && res->f6i != net->ipv6.fib6_null_entry)
138118ec	188	err = fib6_rule_saddr(net, rule, flags, flp6,
effda4dd	189	res->nh->fib_nh_dev);
b2f97f7d DA	190	else
b2f97f7d DA	191	err = -EAGAIN;
138118ec DA	192
	193	return err;
	194	}
	195
	196	static int __fib6_rule_action(struct fib_rule rule, struct flowi flp,
	197	int flags, struct fib_lookup_arg *arg)
101367c2	198	{
a65120ba	199	struct fib6_result *res = arg->result;
4c9483b2	200	struct flowi6 *flp6 = &flp->u.ip6;
101367c2 TG	201	struct rt6_info *rt = NULL;
101367c2 TG	202	struct fib6_table *table;
8ed67789	203	struct net *net = rule->fr_net;
101367c2	204	pol_lookup_t lookup = arg->lookup_ptr;
46b3a421	205	int err = 0;
96c63fa7	206	u32 tb_id;
101367c2 TG	207
	208	switch (rule->action) {
	209	case FR_ACT_TO_TBL:
	210	break;
	211	case FR_ACT_UNREACHABLE:
46b3a421	212	err = -ENETUNREACH;
8ed67789	213	rt = net->ipv6.ip6_null_entry;
101367c2 TG	214	goto discard_pkt;
	215	default:
	216	case FR_ACT_BLACKHOLE:
46b3a421	217	err = -EINVAL;
8ed67789	218	rt = net->ipv6.ip6_blk_hole_entry;
101367c2 TG	219	goto discard_pkt;
101367c2 TG	220	case FR_ACT_PROHIBIT:
46b3a421	221	err = -EACCES;
8ed67789	222	rt = net->ipv6.ip6_prohibit_entry;
101367c2 TG	223	goto discard_pkt;
	224	}
	225
96c63fa7 DA	226	tb_id = fib_rule_get_table(rule, arg);
96c63fa7 DA	227	table = fib6_get_table(net, tb_id);
46b3a421 HFS	228	if (!table) {
	229	err = -EAGAIN;
	230	goto out;
	231	}
101367c2	232
55cced4f BV	233	rt = pol_lookup_func(lookup,
55cced4f BV	234	net, table, flp6, arg->lookup_data, flags);
8ed67789	235	if (rt != net->ipv6.ip6_null_entry) {
cc065a9e DA	236	err = fib6_rule_saddr(net, rule, flags, flp6,
	237	ip6_dst_idev(&rt->dst)->dev);
	238
	239	if (err == -EAGAIN)
	240	goto again;
	241
73ba57bf	242	err = rt->dst.error;
07f61557 SP	243	if (err != -EAGAIN)
07f61557 SP	244	goto out;
29f6af77 YH	245	}
29f6af77 YH	246	again:
d64a1f57	247	ip6_rt_put_flags(rt, flags);
46b3a421	248	err = -EAGAIN;
3226f688 PM	249	rt = NULL;
	250	goto out;
	251
101367c2	252	discard_pkt:
d64a1f57 WW	253	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
d64a1f57 WW	254	dst_hold(&rt->dst);
101367c2	255	out:
a65120ba	256	res->rt6 = rt;
46b3a421	257	return err;
101367c2 TG	258	}
101367c2 TG	259
b9aaec8f BV	260	INDIRECT_CALLABLE_SCOPE int fib6_rule_action(struct fib_rule *rule,
	261	struct flowi *flp, int flags,
	262	struct fib_lookup_arg *arg)
138118ec DA	263	{
	264	if (arg->lookup_ptr == fib6_table_lookup)
	265	return fib6_rule_action_alt(rule, flp, flags, arg);
	266
	267	return __fib6_rule_action(rule, flp, flags, arg);
	268	}
	269
b9aaec8f	270	INDIRECT_CALLABLE_SCOPE bool fib6_rule_suppress(struct fib_rule *rule,
cdef4852	271	int flags,
b9aaec8f	272	struct fib_lookup_arg *arg)
7764a45a	273	{
a65120ba DA	274	struct fib6_result *res = arg->result;
a65120ba DA	275	struct rt6_info *rt = res->rt6;
673498b8 ST	276	struct net_device *dev = NULL;
673498b8 ST	277
a65120ba DA	278	if (!rt)
	279	return false;
	280
673498b8 ST	281	if (rt->rt6i_idev)
	282	dev = rt->rt6i_idev->dev;
	283
7764a45a ST	284	/* do not accept result if the route does
	285	* not meet the required prefix length
	286	*/
73f5698e	287	if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
6ef94cfa ST	288	goto suppress_route;
	289
	290	/* do not accept result if the route uses a device
	291	* belonging to a forbidden interface group
	292	*/
	293	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	294	goto suppress_route;
	295
	296	return false;
	297
	298	suppress_route:
cdef4852	299	ip6_rt_put_flags(rt, flags);
04f0888d	300	return true;
7764a45a	301	}
101367c2	302
b9aaec8f BV	303	INDIRECT_CALLABLE_SCOPE int fib6_rule_match(struct fib_rule *rule,
b9aaec8f BV	304	struct flowi *fl, int flags)
101367c2 TG	305	{
101367c2 TG	306	struct fib6_rule r = (struct fib6_rule ) rule;
4c9483b2	307	struct flowi6 *fl6 = &fl->u.ip6;
101367c2	308
adaa70bb	309	if (r->dst.plen &&
4c9483b2	310	!ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
101367c2 TG	311	return 0;
101367c2 TG	312
29f6af77 YH	313	/*
	314	* If FIB_RULE_FIND_SADDR is set and we do not have a
	315	* source address for the traffic, we defer check for
	316	* source address.
	317	*/
adaa70bb	318	if (r->src.plen) {
29f6af77	319	if (flags & RT6_LOOKUP_F_HAS_SADDR) {
4c9483b2	320	if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
29f6af77 YH	321	r->src.plen))
	322	return 0;
	323	} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
adaa70bb TG	324	return 0;
adaa70bb TG	325	}
101367c2	326
a410a0cf	327	if (r->dscp && r->dscp != ip6_dscp(fl6->flowlabel))
2cc67cc7 YH	328	return 0;
2cc67cc7 YH	329
bb0ad198 RP	330	if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
	331	return 0;
	332
	333	if (fib_rule_port_range_set(&rule->sport_range) &&
	334	!fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport))
	335	return 0;
	336
	337	if (fib_rule_port_range_set(&rule->dport_range) &&
	338	!fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport))
	339	return 0;
	340
101367c2 TG	341	return 1;
	342	}
	343
101367c2	344	static int fib6_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	345	struct fib_rule_hdr *frh,
b16fb418 RP	346	struct nlattr **tb,
b16fb418 RP	347	struct netlink_ext_ack *extack)
101367c2 TG	348	{
101367c2 TG	349	int err = -EINVAL;
3b1e0a65	350	struct net *net = sock_net(skb->sk);
101367c2 TG	351	struct fib6_rule rule6 = (struct fib6_rule ) rule;
101367c2 TG	352
a410a0cf GN	353	if (!inet_validate_dscp(frh->tos)) {
	354	NL_SET_ERR_MSG(extack,
	355	"Invalid dsfield (tos): ECN bits must be 0");
	356	goto errout;
	357	}
	358	rule6->dscp = inet_dsfield_to_dscp(frh->tos);
	359
96c63fa7	360	if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
b16fb418 RP	361	if (rule->table == RT6_TABLE_UNSPEC) {
b16fb418 RP	362	NL_SET_ERR_MSG(extack, "Invalid table");
101367c2	363	goto errout;
b16fb418	364	}
101367c2	365
dcabb819	366	if (fib6_new_table(net, rule->table) == NULL) {
101367c2 TG	367	err = -ENOBUFS;
	368	goto errout;
	369	}
	370	}
	371
e1701c68	372	if (frh->src_len)
67b61f6c	373	rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
101367c2	374
e1701c68	375	if (frh->dst_len)
67b61f6c	376	rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
101367c2 TG	377
	378	rule6->src.plen = frh->src_len;
	379	rule6->dst.plen = frh->dst_len;
101367c2	380
5e5d6fed RP	381	if (fib_rule_requires_fldissect(rule))
	382	net->ipv6.fib6_rules_require_fldissect++;
	383
feca7d8c	384	net->ipv6.fib6_has_custom_rules = true;
101367c2 TG	385	err = 0;
	386	errout:
	387	return err;
	388	}
	389
5e5d6fed RP	390	static int fib6_rule_delete(struct fib_rule *rule)
	391	{
	392	struct net *net = rule->fr_net;
	393
	394	if (net->ipv6.fib6_rules_require_fldissect &&
	395	fib_rule_requires_fldissect(rule))
	396	net->ipv6.fib6_rules_require_fldissect--;
	397
	398	return 0;
	399	}
	400
101367c2 TG	401	static int fib6_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
	402	struct nlattr **tb)
	403	{
	404	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	405
	406	if (frh->src_len && (rule6->src.plen != frh->src_len))
	407	return 0;
	408
	409	if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
	410	return 0;
	411
a410a0cf	412	if (frh->tos && inet_dscp_to_dsfield(rule6->dscp) != frh->tos)
101367c2 TG	413	return 0;
101367c2 TG	414
e1701c68	415	if (frh->src_len &&
101367c2 TG	416	nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
	417	return 0;
	418
e1701c68	419	if (frh->dst_len &&
101367c2 TG	420	nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
	421	return 0;
	422
	423	return 1;
	424	}
	425
	426	static int fib6_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	427	struct fib_rule_hdr *frh)
101367c2 TG	428	{
	429	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	430
101367c2 TG	431	frh->dst_len = rule6->dst.plen;
101367c2 TG	432	frh->src_len = rule6->src.plen;
a410a0cf	433	frh->tos = inet_dscp_to_dsfield(rule6->dscp);
101367c2	434
c78679e8	435	if ((rule6->dst.plen &&
930345ea	436	nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) \|\|
c78679e8	437	(rule6->src.plen &&
930345ea	438	nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
c78679e8	439	goto nla_put_failure;
101367c2 TG	440	return 0;
	441
	442	nla_put_failure:
	443	return -ENOBUFS;
	444	}
	445
339bf98f TG	446	static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
	447	{
	448	return nla_total_size(16) /* dst */
	449	+ nla_total_size(16); /* src */
	450	}
	451
04a6f82c	452	static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
25239cee	453	.family = AF_INET6,
101367c2	454	.rule_size = sizeof(struct fib6_rule),
e1701c68	455	.addr_size = sizeof(struct in6_addr),
101367c2 TG	456	.action = fib6_rule_action,
101367c2 TG	457	.match = fib6_rule_match,
7764a45a	458	.suppress = fib6_rule_suppress,
101367c2	459	.configure = fib6_rule_configure,
5e5d6fed	460	.delete = fib6_rule_delete,
101367c2 TG	461	.compare = fib6_rule_compare,
101367c2 TG	462	.fill = fib6_rule_fill,
339bf98f	463	.nlmsg_payload = fib6_rule_nlmsg_payload,
101367c2	464	.nlgroup = RTNLGRP_IPV6_RULE,
101367c2	465	.owner = THIS_MODULE,
03592383	466	.fro_net = &init_net,
101367c2 TG	467	};
101367c2 TG	468
2c8c1e72	469	static int __net_init fib6_rules_net_init(struct net *net)
101367c2	470	{
e9c5158a	471	struct fib_rules_ops *ops;
b5ec0705	472	int err;
2994c638	473
e9c5158a EB	474	ops = fib_rules_register(&fib6_rules_ops_template, net);
	475	if (IS_ERR(ops))
	476	return PTR_ERR(ops);
eb5564b8	477
85b99092	478	err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0);
dcabb819 DL	479	if (err)
dcabb819 DL	480	goto out_fib6_rules_ops;
9eb87f3f	481
85b99092	482	err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0);
dcabb819	483	if (err)
e9c5158a	484	goto out_fib6_rules_ops;
9eb87f3f	485
85b99092	486	net->ipv6.fib6_rules_ops = ops;
5e5d6fed	487	net->ipv6.fib6_rules_require_fldissect = 0;
9eb87f3f	488	out:
dcabb819	489	return err;
9eb87f3f	490
dcabb819	491	out_fib6_rules_ops:
e9c5158a	492	fib_rules_unregister(ops);
9eb87f3f	493	goto out;
101367c2 TG	494	}
101367c2 TG	495
ea3e9166	496	static void __net_exit fib6_rules_net_exit_batch(struct list_head *net_list)
dcabb819	497	{
ea3e9166 ED	498	struct net *net;
ea3e9166 ED	499
419df12f	500	rtnl_lock();
ea3e9166 ED	501	list_for_each_entry(net, net_list, exit_list) {
	502	fib_rules_unregister(net->ipv6.fib6_rules_ops);
	503	cond_resched();
	504	}
419df12f	505	rtnl_unlock();
dcabb819 DL	506	}
	507
	508	static struct pernet_operations fib6_rules_net_ops = {
	509	.init = fib6_rules_net_init,
ea3e9166	510	.exit_batch = fib6_rules_net_exit_batch,
dcabb819 DL	511	};
	512
	513	int __init fib6_rules_init(void)
	514	{
	515	return register_pernet_subsys(&fib6_rules_net_ops);
	516	}
	517
	518
101367c2 TG	519	void fib6_rules_cleanup(void)
101367c2 TG	520	{
ff4e1fb0	521	unregister_pernet_subsys(&fib6_rules_net_ops);
101367c2	522	}