[mirror_ubuntu-jammy-kernel.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,
		    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 = 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:
	if (!(arg->flags & FIB_LOOKUP_NOREF))
		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
b7a59557 JP	50	int fib6_rules_dump(struct net net, struct notifier_block nb,
b7a59557 JP	51	struct netlink_ext_ack *extack)
dcb18f76	52	{
b7a59557	53	return fib_rules_dump(net, nb, AF_INET6, extack);
dcb18f76 IS	54	}
	55
	56	unsigned int fib6_rules_seq_read(struct net *net)
	57	{
	58	return fib_rules_seq_read(net, AF_INET6);
	59	}
	60
138118ec	61	/* called with rcu lock held; no reference taken on fib6_info */
effda4dd DA	62	int fib6_lookup(struct net net, int oif, struct flowi6 fl6,
effda4dd DA	63	struct fib6_result *res, int flags)
138118ec	64	{
138118ec DA	65	int err;
	66
	67	if (net->ipv6.fib6_has_custom_rules) {
	68	struct fib_lookup_arg arg = {
	69	.lookup_ptr = fib6_table_lookup,
	70	.lookup_data = &oif,
effda4dd	71	.result = res,
138118ec DA	72	.flags = FIB_LOOKUP_NOREF,
	73	};
	74
	75	l3mdev_update_flow(net, flowi6_to_flowi(fl6));
	76
	77	err = fib_rules_lookup(net->ipv6.fib6_rules_ops,
	78	flowi6_to_flowi(fl6), flags, &arg);
138118ec	79	} else {
effda4dd DA	80	err = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, oif,
	81	fl6, res, flags);
	82	if (err \|\| res->f6i == net->ipv6.fib6_null_entry)
	83	err = fib6_table_lookup(net, net->ipv6.fib6_main_tbl,
	84	oif, fl6, res, flags);
138118ec DA	85	}
138118ec DA	86
effda4dd	87	return err;
138118ec DA	88	}
138118ec DA	89
4c9483b2	90	struct dst_entry fib6_rule_lookup(struct net net, struct flowi6 *fl6,
b75cc8f9	91	const struct sk_buff *skb,
58f09b78	92	int flags, pol_lookup_t lookup)
101367c2	93	{
feca7d8c	94	if (net->ipv6.fib6_has_custom_rules) {
a65120ba	95	struct fib6_result res = {};
feca7d8c VB	96	struct fib_lookup_arg arg = {
feca7d8c VB	97	.lookup_ptr = lookup,
b75cc8f9	98	.lookup_data = skb,
a65120ba	99	.result = &res,
feca7d8c VB	100	.flags = FIB_LOOKUP_NOREF,
	101	};
	102
	103	/* update flow if oif or iif point to device enslaved to l3mdev */
	104	l3mdev_update_flow(net, flowi6_to_flowi(fl6));
	105
	106	fib_rules_lookup(net->ipv6.fib6_rules_ops,
	107	flowi6_to_flowi(fl6), flags, &arg);
	108
a65120ba DA	109	if (res.rt6)
a65120ba DA	110	return &res.rt6->dst;
feca7d8c VB	111	} else {
	112	struct rt6_info *rt;
	113
b75cc8f9	114	rt = lookup(net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
feca7d8c VB	115	if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
feca7d8c VB	116	return &rt->dst;
d64a1f57	117	ip6_rt_put_flags(rt, flags);
b75cc8f9	118	rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
feca7d8c VB	119	if (rt->dst.error != -EAGAIN)
feca7d8c VB	120	return &rt->dst;
d64a1f57	121	ip6_rt_put_flags(rt, flags);
feca7d8c	122	}
b1429553	123
d64a1f57 WW	124	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
d64a1f57 WW	125	dst_hold(&net->ipv6.ip6_null_entry->dst);
07f61557	126	return &net->ipv6.ip6_null_entry->dst;
101367c2 TG	127	}
101367c2 TG	128
cc065a9e DA	129	static int fib6_rule_saddr(struct net net, struct fib_rule rule, int flags,
	130	struct flowi6 flp6, const struct net_device dev)
	131	{
	132	struct fib6_rule r = (struct fib6_rule )rule;
	133
	134	/* If we need to find a source address for this traffic,
	135	* we check the result if it meets requirement of the rule.
	136	*/
	137	if ((rule->flags & FIB_RULE_FIND_SADDR) &&
	138	r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
	139	struct in6_addr saddr;
	140
	141	if (ipv6_dev_get_saddr(net, dev, &flp6->daddr,
	142	rt6_flags2srcprefs(flags), &saddr))
	143	return -EAGAIN;
	144
	145	if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
	146	return -EAGAIN;
	147
	148	flp6->saddr = saddr;
	149	}
	150
	151	return 0;
	152	}
	153
138118ec DA	154	static int fib6_rule_action_alt(struct fib_rule rule, struct flowi flp,
	155	int flags, struct fib_lookup_arg *arg)
	156	{
effda4dd	157	struct fib6_result *res = arg->result;
138118ec DA	158	struct flowi6 *flp6 = &flp->u.ip6;
	159	struct net *net = rule->fr_net;
	160	struct fib6_table *table;
b2f97f7d	161	int err, *oif;
138118ec DA	162	u32 tb_id;
	163
	164	switch (rule->action) {
	165	case FR_ACT_TO_TBL:
	166	break;
	167	case FR_ACT_UNREACHABLE:
	168	return -ENETUNREACH;
	169	case FR_ACT_PROHIBIT:
	170	return -EACCES;
	171	case FR_ACT_BLACKHOLE:
	172	default:
	173	return -EINVAL;
	174	}
	175
	176	tb_id = fib_rule_get_table(rule, arg);
	177	table = fib6_get_table(net, tb_id);
	178	if (!table)
	179	return -EAGAIN;
	180
	181	oif = (int *)arg->lookup_data;
effda4dd DA	182	err = fib6_table_lookup(net, table, *oif, flp6, res, flags);
effda4dd DA	183	if (!err && res->f6i != net->ipv6.fib6_null_entry)
138118ec	184	err = fib6_rule_saddr(net, rule, flags, flp6,
effda4dd	185	res->nh->fib_nh_dev);
b2f97f7d DA	186	else
b2f97f7d DA	187	err = -EAGAIN;
138118ec DA	188
	189	return err;
	190	}
	191
	192	static int __fib6_rule_action(struct fib_rule rule, struct flowi flp,
	193	int flags, struct fib_lookup_arg *arg)
101367c2	194	{
a65120ba	195	struct fib6_result *res = arg->result;
4c9483b2	196	struct flowi6 *flp6 = &flp->u.ip6;
101367c2 TG	197	struct rt6_info *rt = NULL;
101367c2 TG	198	struct fib6_table *table;
8ed67789	199	struct net *net = rule->fr_net;
101367c2	200	pol_lookup_t lookup = arg->lookup_ptr;
46b3a421	201	int err = 0;
96c63fa7	202	u32 tb_id;
101367c2 TG	203
	204	switch (rule->action) {
	205	case FR_ACT_TO_TBL:
	206	break;
	207	case FR_ACT_UNREACHABLE:
46b3a421	208	err = -ENETUNREACH;
8ed67789	209	rt = net->ipv6.ip6_null_entry;
101367c2 TG	210	goto discard_pkt;
	211	default:
	212	case FR_ACT_BLACKHOLE:
46b3a421	213	err = -EINVAL;
8ed67789	214	rt = net->ipv6.ip6_blk_hole_entry;
101367c2 TG	215	goto discard_pkt;
101367c2 TG	216	case FR_ACT_PROHIBIT:
46b3a421	217	err = -EACCES;
8ed67789	218	rt = net->ipv6.ip6_prohibit_entry;
101367c2 TG	219	goto discard_pkt;
	220	}
	221
96c63fa7 DA	222	tb_id = fib_rule_get_table(rule, arg);
96c63fa7 DA	223	table = fib6_get_table(net, tb_id);
46b3a421 HFS	224	if (!table) {
	225	err = -EAGAIN;
	226	goto out;
	227	}
101367c2	228
b75cc8f9	229	rt = lookup(net, table, flp6, arg->lookup_data, flags);
8ed67789	230	if (rt != net->ipv6.ip6_null_entry) {
cc065a9e DA	231	err = fib6_rule_saddr(net, rule, flags, flp6,
	232	ip6_dst_idev(&rt->dst)->dev);
	233
	234	if (err == -EAGAIN)
	235	goto again;
	236
73ba57bf	237	err = rt->dst.error;
07f61557 SP	238	if (err != -EAGAIN)
07f61557 SP	239	goto out;
29f6af77 YH	240	}
29f6af77 YH	241	again:
d64a1f57	242	ip6_rt_put_flags(rt, flags);
46b3a421	243	err = -EAGAIN;
3226f688 PM	244	rt = NULL;
	245	goto out;
	246
101367c2	247	discard_pkt:
d64a1f57 WW	248	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
d64a1f57 WW	249	dst_hold(&rt->dst);
101367c2	250	out:
a65120ba	251	res->rt6 = rt;
46b3a421	252	return err;
101367c2 TG	253	}
101367c2 TG	254
138118ec DA	255	static int fib6_rule_action(struct fib_rule rule, struct flowi flp,
	256	int flags, struct fib_lookup_arg *arg)
	257	{
	258	if (arg->lookup_ptr == fib6_table_lookup)
	259	return fib6_rule_action_alt(rule, flp, flags, arg);
	260
	261	return __fib6_rule_action(rule, flp, flags, arg);
	262	}
	263
7764a45a ST	264	static bool fib6_rule_suppress(struct fib_rule rule, struct fib_lookup_arg arg)
7764a45a ST	265	{
a65120ba DA	266	struct fib6_result *res = arg->result;
a65120ba DA	267	struct rt6_info *rt = res->rt6;
673498b8 ST	268	struct net_device *dev = NULL;
673498b8 ST	269
a65120ba DA	270	if (!rt)
	271	return false;
	272
673498b8 ST	273	if (rt->rt6i_idev)
	274	dev = rt->rt6i_idev->dev;
	275
7764a45a ST	276	/* do not accept result if the route does
	277	* not meet the required prefix length
	278	*/
73f5698e	279	if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
6ef94cfa ST	280	goto suppress_route;
	281
	282	/* do not accept result if the route uses a device
	283	* belonging to a forbidden interface group
	284	*/
	285	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
	286	goto suppress_route;
	287
	288	return false;
	289
	290	suppress_route:
ca7a03c4 JD	291	if (!(arg->flags & FIB_LOOKUP_NOREF))
ca7a03c4 JD	292	ip6_rt_put(rt);
04f0888d	293	return true;
7764a45a	294	}
101367c2 TG	295
	296	static int fib6_rule_match(struct fib_rule rule, struct flowi fl, int flags)
	297	{
	298	struct fib6_rule r = (struct fib6_rule ) rule;
4c9483b2	299	struct flowi6 *fl6 = &fl->u.ip6;
101367c2	300
adaa70bb	301	if (r->dst.plen &&
4c9483b2	302	!ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
101367c2 TG	303	return 0;
101367c2 TG	304
29f6af77 YH	305	/*
	306	* If FIB_RULE_FIND_SADDR is set and we do not have a
	307	* source address for the traffic, we defer check for
	308	* source address.
	309	*/
adaa70bb	310	if (r->src.plen) {
29f6af77	311	if (flags & RT6_LOOKUP_F_HAS_SADDR) {
4c9483b2	312	if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
29f6af77 YH	313	r->src.plen))
	314	return 0;
	315	} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
adaa70bb TG	316	return 0;
adaa70bb TG	317	}
101367c2	318
d76ed22b	319	if (r->tclass && r->tclass != ip6_tclass(fl6->flowlabel))
2cc67cc7 YH	320	return 0;
2cc67cc7 YH	321
bb0ad198 RP	322	if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
	323	return 0;
	324
	325	if (fib_rule_port_range_set(&rule->sport_range) &&
	326	!fib_rule_port_inrange(&rule->sport_range, fl6->fl6_sport))
	327	return 0;
	328
	329	if (fib_rule_port_range_set(&rule->dport_range) &&
	330	!fib_rule_port_inrange(&rule->dport_range, fl6->fl6_dport))
	331	return 0;
	332
101367c2 TG	333	return 1;
	334	}
	335
ef7c79ed	336	static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
1f6c9557	337	FRA_GENERIC_POLICY,
101367c2 TG	338	};
	339
	340	static int fib6_rule_configure(struct fib_rule rule, struct sk_buff skb,
8b3521ee	341	struct fib_rule_hdr *frh,
b16fb418 RP	342	struct nlattr **tb,
b16fb418 RP	343	struct netlink_ext_ack *extack)
101367c2 TG	344	{
101367c2 TG	345	int err = -EINVAL;
3b1e0a65	346	struct net *net = sock_net(skb->sk);
101367c2 TG	347	struct fib6_rule rule6 = (struct fib6_rule ) rule;
101367c2 TG	348
96c63fa7	349	if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
b16fb418 RP	350	if (rule->table == RT6_TABLE_UNSPEC) {
b16fb418 RP	351	NL_SET_ERR_MSG(extack, "Invalid table");
101367c2	352	goto errout;
b16fb418	353	}
101367c2	354
dcabb819	355	if (fib6_new_table(net, rule->table) == NULL) {
101367c2 TG	356	err = -ENOBUFS;
	357	goto errout;
	358	}
	359	}
	360
e1701c68	361	if (frh->src_len)
67b61f6c	362	rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
101367c2	363
e1701c68	364	if (frh->dst_len)
67b61f6c	365	rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
101367c2 TG	366
	367	rule6->src.plen = frh->src_len;
	368	rule6->dst.plen = frh->dst_len;
	369	rule6->tclass = frh->tos;
	370
5e5d6fed RP	371	if (fib_rule_requires_fldissect(rule))
	372	net->ipv6.fib6_rules_require_fldissect++;
	373
feca7d8c	374	net->ipv6.fib6_has_custom_rules = true;
101367c2 TG	375	err = 0;
	376	errout:
	377	return err;
	378	}
	379
5e5d6fed RP	380	static int fib6_rule_delete(struct fib_rule *rule)
	381	{
	382	struct net *net = rule->fr_net;
	383
	384	if (net->ipv6.fib6_rules_require_fldissect &&
	385	fib_rule_requires_fldissect(rule))
	386	net->ipv6.fib6_rules_require_fldissect--;
	387
	388	return 0;
	389	}
	390
101367c2 TG	391	static int fib6_rule_compare(struct fib_rule rule, struct fib_rule_hdr frh,
	392	struct nlattr **tb)
	393	{
	394	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	395
	396	if (frh->src_len && (rule6->src.plen != frh->src_len))
	397	return 0;
	398
	399	if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
	400	return 0;
	401
	402	if (frh->tos && (rule6->tclass != frh->tos))
	403	return 0;
	404
e1701c68	405	if (frh->src_len &&
101367c2 TG	406	nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
	407	return 0;
	408
e1701c68	409	if (frh->dst_len &&
101367c2 TG	410	nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
	411	return 0;
	412
	413	return 1;
	414	}
	415
	416	static int fib6_rule_fill(struct fib_rule rule, struct sk_buff skb,
04af8cf6	417	struct fib_rule_hdr *frh)
101367c2 TG	418	{
	419	struct fib6_rule rule6 = (struct fib6_rule ) rule;
	420
101367c2 TG	421	frh->dst_len = rule6->dst.plen;
	422	frh->src_len = rule6->src.plen;
	423	frh->tos = rule6->tclass;
	424
c78679e8	425	if ((rule6->dst.plen &&
930345ea	426	nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) \|\|
c78679e8	427	(rule6->src.plen &&
930345ea	428	nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
c78679e8	429	goto nla_put_failure;
101367c2 TG	430	return 0;
	431
	432	nla_put_failure:
	433	return -ENOBUFS;
	434	}
	435
339bf98f TG	436	static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
	437	{
	438	return nla_total_size(16) /* dst */
	439	+ nla_total_size(16); /* src */
	440	}
	441
04a6f82c	442	static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
25239cee	443	.family = AF_INET6,
101367c2	444	.rule_size = sizeof(struct fib6_rule),
e1701c68	445	.addr_size = sizeof(struct in6_addr),
101367c2 TG	446	.action = fib6_rule_action,
101367c2 TG	447	.match = fib6_rule_match,
7764a45a	448	.suppress = fib6_rule_suppress,
101367c2	449	.configure = fib6_rule_configure,
5e5d6fed	450	.delete = fib6_rule_delete,
101367c2 TG	451	.compare = fib6_rule_compare,
101367c2 TG	452	.fill = fib6_rule_fill,
339bf98f	453	.nlmsg_payload = fib6_rule_nlmsg_payload,
101367c2 TG	454	.nlgroup = RTNLGRP_IPV6_RULE,
101367c2 TG	455	.policy = fib6_rule_policy,
101367c2	456	.owner = THIS_MODULE,
03592383	457	.fro_net = &init_net,
101367c2 TG	458	};
101367c2 TG	459
2c8c1e72	460	static int __net_init fib6_rules_net_init(struct net *net)
101367c2	461	{
e9c5158a	462	struct fib_rules_ops *ops;
dcabb819	463	int err = -ENOMEM;
2994c638	464
e9c5158a EB	465	ops = fib_rules_register(&fib6_rules_ops_template, net);
	466	if (IS_ERR(ops))
	467	return PTR_ERR(ops);
eb5564b8	468
85b99092	469	err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL, 0);
dcabb819 DL	470	if (err)
dcabb819 DL	471	goto out_fib6_rules_ops;
9eb87f3f	472
85b99092	473	err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN, 0);
dcabb819	474	if (err)
e9c5158a	475	goto out_fib6_rules_ops;
9eb87f3f	476
85b99092	477	net->ipv6.fib6_rules_ops = ops;
5e5d6fed	478	net->ipv6.fib6_rules_require_fldissect = 0;
9eb87f3f	479	out:
dcabb819	480	return err;
9eb87f3f	481
dcabb819	482	out_fib6_rules_ops:
e9c5158a	483	fib_rules_unregister(ops);
9eb87f3f	484	goto out;
101367c2 TG	485	}
101367c2 TG	486
2c8c1e72	487	static void __net_exit fib6_rules_net_exit(struct net *net)
dcabb819	488	{
419df12f	489	rtnl_lock();
dcabb819	490	fib_rules_unregister(net->ipv6.fib6_rules_ops);
419df12f	491	rtnl_unlock();
dcabb819 DL	492	}
	493
	494	static struct pernet_operations fib6_rules_net_ops = {
	495	.init = fib6_rules_net_init,
	496	.exit = fib6_rules_net_exit,
	497	};
	498
	499	int __init fib6_rules_init(void)
	500	{
	501	return register_pernet_subsys(&fib6_rules_net_ops);
	502	}
	503
	504
101367c2 TG	505	void fib6_rules_cleanup(void)
101367c2 TG	506	{
ff4e1fb0	507	unregister_pernet_subsys(&fib6_rules_net_ops);
101367c2	508	}