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v3.15
 
  1/*
  2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
  3 *		operating system.  INET is implemented using the  BSD Socket
  4 *		interface as the means of communication with the user level.
  5 *
  6 *		IPv4 Forwarding Information Base: policy rules.
  7 *
  8 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  9 *		Thomas Graf <tgraf@suug.ch>
 10 *
 11 *		This program is free software; you can redistribute it and/or
 12 *		modify it under the terms of the GNU General Public License
 13 *		as published by the Free Software Foundation; either version
 14 *		2 of the License, or (at your option) any later version.
 15 *
 16 * Fixes:
 17 *		Rani Assaf	:	local_rule cannot be deleted
 18 *		Marc Boucher	:	routing by fwmark
 19 */
 20
 21#include <linux/types.h>
 22#include <linux/kernel.h>
 23#include <linux/netdevice.h>
 24#include <linux/netlink.h>
 25#include <linux/inetdevice.h>
 26#include <linux/init.h>
 27#include <linux/list.h>
 28#include <linux/rcupdate.h>
 29#include <linux/export.h>
 30#include <net/ip.h>
 31#include <net/route.h>
 32#include <net/tcp.h>
 33#include <net/ip_fib.h>
 
 34#include <net/fib_rules.h>
 
 35
 36struct fib4_rule {
 37	struct fib_rule		common;
 38	u8			dst_len;
 39	u8			src_len;
 40	u8			tos;
 41	__be32			src;
 42	__be32			srcmask;
 43	__be32			dst;
 44	__be32			dstmask;
 45#ifdef CONFIG_IP_ROUTE_CLASSID
 46	u32			tclassid;
 47#endif
 48};
 49
 50int __fib_lookup(struct net *net, struct flowi4 *flp, struct fib_result *res)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 51{
 52	struct fib_lookup_arg arg = {
 53		.result = res,
 54		.flags = FIB_LOOKUP_NOREF,
 55	};
 56	int err;
 57
 
 
 
 58	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
 59#ifdef CONFIG_IP_ROUTE_CLASSID
 60	if (arg.rule)
 61		res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
 62	else
 63		res->tclassid = 0;
 64#endif
 
 
 
 
 65	return err;
 66}
 67EXPORT_SYMBOL_GPL(__fib_lookup);
 68
 69static int fib4_rule_action(struct fib_rule *rule, struct flowi *flp,
 70			    int flags, struct fib_lookup_arg *arg)
 
 71{
 72	int err = -EAGAIN;
 73	struct fib_table *tbl;
 
 74
 75	switch (rule->action) {
 76	case FR_ACT_TO_TBL:
 77		break;
 78
 79	case FR_ACT_UNREACHABLE:
 80		err = -ENETUNREACH;
 81		goto errout;
 82
 83	case FR_ACT_PROHIBIT:
 84		err = -EACCES;
 85		goto errout;
 86
 87	case FR_ACT_BLACKHOLE:
 88	default:
 89		err = -EINVAL;
 90		goto errout;
 91	}
 92
 93	tbl = fib_get_table(rule->fr_net, rule->table);
 94	if (!tbl)
 95		goto errout;
 96
 97	err = fib_table_lookup(tbl, &flp->u.ip4, (struct fib_result *) arg->result, arg->flags);
 98	if (err > 0)
 99		err = -EAGAIN;
100errout:
 
 
 
 
101	return err;
102}
103
104static bool fib4_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
 
105{
106	struct fib_result *result = (struct fib_result *) arg->result;
107	struct net_device *dev = NULL;
108
109	if (result->fi)
110		dev = result->fi->fib_dev;
 
 
 
111
112	/* do not accept result if the route does
113	 * not meet the required prefix length
114	 */
115	if (result->prefixlen <= rule->suppress_prefixlen)
116		goto suppress_route;
117
118	/* do not accept result if the route uses a device
119	 * belonging to a forbidden interface group
120	 */
121	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
122		goto suppress_route;
123
124	return false;
125
126suppress_route:
127	if (!(arg->flags & FIB_LOOKUP_NOREF))
128		fib_info_put(result->fi);
129	return true;
130}
131
132static int fib4_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
 
133{
134	struct fib4_rule *r = (struct fib4_rule *) rule;
135	struct flowi4 *fl4 = &fl->u.ip4;
136	__be32 daddr = fl4->daddr;
137	__be32 saddr = fl4->saddr;
138
139	if (((saddr ^ r->src) & r->srcmask) ||
140	    ((daddr ^ r->dst) & r->dstmask))
141		return 0;
142
143	if (r->tos && (r->tos != fl4->flowi4_tos))
144		return 0;
145
 
 
 
 
 
 
 
 
 
 
 
146	return 1;
147}
148
149static struct fib_table *fib_empty_table(struct net *net)
150{
151	u32 id;
152
153	for (id = 1; id <= RT_TABLE_MAX; id++)
154		if (fib_get_table(net, id) == NULL)
155			return fib_new_table(net, id);
 
 
 
 
156	return NULL;
157}
158
159static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
160	FRA_GENERIC_POLICY,
161	[FRA_FLOW]	= { .type = NLA_U32 },
162};
163
164static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
165			       struct fib_rule_hdr *frh,
166			       struct nlattr **tb)
 
167{
168	struct net *net = sock_net(skb->sk);
169	int err = -EINVAL;
170	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
171
172	if (frh->tos & ~IPTOS_TOS_MASK)
 
173		goto errout;
 
174
175	if (rule->table == RT_TABLE_UNSPEC) {
 
 
 
 
 
176		if (rule->action == FR_ACT_TO_TBL) {
177			struct fib_table *table;
178
179			table = fib_empty_table(net);
180			if (table == NULL) {
181				err = -ENOBUFS;
182				goto errout;
183			}
184
185			rule->table = table->tb_id;
186		}
187	}
188
189	if (frh->src_len)
190		rule4->src = nla_get_be32(tb[FRA_SRC]);
191
192	if (frh->dst_len)
193		rule4->dst = nla_get_be32(tb[FRA_DST]);
194
195#ifdef CONFIG_IP_ROUTE_CLASSID
196	if (tb[FRA_FLOW]) {
197		rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
198		if (rule4->tclassid)
199			net->ipv4.fib_num_tclassid_users++;
200	}
201#endif
202
 
 
 
203	rule4->src_len = frh->src_len;
204	rule4->srcmask = inet_make_mask(rule4->src_len);
205	rule4->dst_len = frh->dst_len;
206	rule4->dstmask = inet_make_mask(rule4->dst_len);
207	rule4->tos = frh->tos;
208
209	net->ipv4.fib_has_custom_rules = true;
 
210	err = 0;
211errout:
212	return err;
213}
214
215static void fib4_rule_delete(struct fib_rule *rule)
216{
217	struct net *net = rule->fr_net;
218#ifdef CONFIG_IP_ROUTE_CLASSID
219	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
220
221	if (rule4->tclassid)
 
 
 
 
 
 
222		net->ipv4.fib_num_tclassid_users--;
223#endif
224	net->ipv4.fib_has_custom_rules = true;
 
 
 
 
 
 
225}
226
227static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
228			     struct nlattr **tb)
229{
230	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
231
232	if (frh->src_len && (rule4->src_len != frh->src_len))
233		return 0;
234
235	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
236		return 0;
237
238	if (frh->tos && (rule4->tos != frh->tos))
239		return 0;
240
241#ifdef CONFIG_IP_ROUTE_CLASSID
242	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
243		return 0;
244#endif
245
246	if (frh->src_len && (rule4->src != nla_get_be32(tb[FRA_SRC])))
247		return 0;
248
249	if (frh->dst_len && (rule4->dst != nla_get_be32(tb[FRA_DST])))
250		return 0;
251
252	return 1;
253}
254
255static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
256			  struct fib_rule_hdr *frh)
257{
258	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
259
260	frh->dst_len = rule4->dst_len;
261	frh->src_len = rule4->src_len;
262	frh->tos = rule4->tos;
263
264	if ((rule4->dst_len &&
265	     nla_put_be32(skb, FRA_DST, rule4->dst)) ||
266	    (rule4->src_len &&
267	     nla_put_be32(skb, FRA_SRC, rule4->src)))
268		goto nla_put_failure;
269#ifdef CONFIG_IP_ROUTE_CLASSID
270	if (rule4->tclassid &&
271	    nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
272		goto nla_put_failure;
273#endif
274	return 0;
275
276nla_put_failure:
277	return -ENOBUFS;
278}
279
280static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
281{
282	return nla_total_size(4) /* dst */
283	       + nla_total_size(4) /* src */
284	       + nla_total_size(4); /* flow */
285}
286
287static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
288{
289	rt_cache_flush(ops->fro_net);
290}
291
292static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
293	.family		= AF_INET,
294	.rule_size	= sizeof(struct fib4_rule),
295	.addr_size	= sizeof(u32),
296	.action		= fib4_rule_action,
297	.suppress	= fib4_rule_suppress,
298	.match		= fib4_rule_match,
299	.configure	= fib4_rule_configure,
300	.delete		= fib4_rule_delete,
301	.compare	= fib4_rule_compare,
302	.fill		= fib4_rule_fill,
303	.default_pref	= fib_default_rule_pref,
304	.nlmsg_payload	= fib4_rule_nlmsg_payload,
305	.flush_cache	= fib4_rule_flush_cache,
306	.nlgroup	= RTNLGRP_IPV4_RULE,
307	.policy		= fib4_rule_policy,
308	.owner		= THIS_MODULE,
309};
310
311static int fib_default_rules_init(struct fib_rules_ops *ops)
312{
313	int err;
314
315	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
316	if (err < 0)
317		return err;
318	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
319	if (err < 0)
320		return err;
321	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
322	if (err < 0)
323		return err;
324	return 0;
325}
326
327int __net_init fib4_rules_init(struct net *net)
328{
329	int err;
330	struct fib_rules_ops *ops;
331
332	ops = fib_rules_register(&fib4_rules_ops_template, net);
333	if (IS_ERR(ops))
334		return PTR_ERR(ops);
335
336	err = fib_default_rules_init(ops);
337	if (err < 0)
338		goto fail;
339	net->ipv4.rules_ops = ops;
340	net->ipv4.fib_has_custom_rules = false;
 
341	return 0;
342
343fail:
344	/* also cleans all rules already added */
345	fib_rules_unregister(ops);
346	return err;
347}
348
349void __net_exit fib4_rules_exit(struct net *net)
350{
351	fib_rules_unregister(net->ipv4.rules_ops);
352}
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
  4 *		operating system.  INET is implemented using the  BSD Socket
  5 *		interface as the means of communication with the user level.
  6 *
  7 *		IPv4 Forwarding Information Base: policy rules.
  8 *
  9 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 10 *		Thomas Graf <tgraf@suug.ch>
 11 *
 
 
 
 
 
 12 * Fixes:
 13 *		Rani Assaf	:	local_rule cannot be deleted
 14 *		Marc Boucher	:	routing by fwmark
 15 */
 16
 17#include <linux/types.h>
 18#include <linux/kernel.h>
 19#include <linux/netdevice.h>
 20#include <linux/netlink.h>
 21#include <linux/inetdevice.h>
 22#include <linux/init.h>
 23#include <linux/list.h>
 24#include <linux/rcupdate.h>
 25#include <linux/export.h>
 26#include <net/ip.h>
 27#include <net/route.h>
 28#include <net/tcp.h>
 29#include <net/ip_fib.h>
 30#include <net/nexthop.h>
 31#include <net/fib_rules.h>
 32#include <linux/indirect_call_wrapper.h>
 33
 34struct fib4_rule {
 35	struct fib_rule		common;
 36	u8			dst_len;
 37	u8			src_len;
 38	u8			tos;
 39	__be32			src;
 40	__be32			srcmask;
 41	__be32			dst;
 42	__be32			dstmask;
 43#ifdef CONFIG_IP_ROUTE_CLASSID
 44	u32			tclassid;
 45#endif
 46};
 47
 48static bool fib4_rule_matchall(const struct fib_rule *rule)
 49{
 50	struct fib4_rule *r = container_of(rule, struct fib4_rule, common);
 51
 52	if (r->dst_len || r->src_len || r->tos)
 53		return false;
 54	return fib_rule_matchall(rule);
 55}
 56
 57bool fib4_rule_default(const struct fib_rule *rule)
 58{
 59	if (!fib4_rule_matchall(rule) || rule->action != FR_ACT_TO_TBL ||
 60	    rule->l3mdev)
 61		return false;
 62	if (rule->table != RT_TABLE_LOCAL && rule->table != RT_TABLE_MAIN &&
 63	    rule->table != RT_TABLE_DEFAULT)
 64		return false;
 65	return true;
 66}
 67EXPORT_SYMBOL_GPL(fib4_rule_default);
 68
 69int fib4_rules_dump(struct net *net, struct notifier_block *nb,
 70		    struct netlink_ext_ack *extack)
 71{
 72	return fib_rules_dump(net, nb, AF_INET, extack);
 73}
 74
 75unsigned int fib4_rules_seq_read(struct net *net)
 76{
 77	return fib_rules_seq_read(net, AF_INET);
 78}
 79
 80int __fib_lookup(struct net *net, struct flowi4 *flp,
 81		 struct fib_result *res, unsigned int flags)
 82{
 83	struct fib_lookup_arg arg = {
 84		.result = res,
 85		.flags = flags,
 86	};
 87	int err;
 88
 89	/* update flow if oif or iif point to device enslaved to l3mdev */
 90	l3mdev_update_flow(net, flowi4_to_flowi(flp));
 91
 92	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
 93#ifdef CONFIG_IP_ROUTE_CLASSID
 94	if (arg.rule)
 95		res->tclassid = ((struct fib4_rule *)arg.rule)->tclassid;
 96	else
 97		res->tclassid = 0;
 98#endif
 99
100	if (err == -ESRCH)
101		err = -ENETUNREACH;
102
103	return err;
104}
105EXPORT_SYMBOL_GPL(__fib_lookup);
106
107INDIRECT_CALLABLE_SCOPE int fib4_rule_action(struct fib_rule *rule,
108					     struct flowi *flp, int flags,
109					     struct fib_lookup_arg *arg)
110{
111	int err = -EAGAIN;
112	struct fib_table *tbl;
113	u32 tb_id;
114
115	switch (rule->action) {
116	case FR_ACT_TO_TBL:
117		break;
118
119	case FR_ACT_UNREACHABLE:
120		return -ENETUNREACH;
 
121
122	case FR_ACT_PROHIBIT:
123		return -EACCES;
 
124
125	case FR_ACT_BLACKHOLE:
126	default:
127		return -EINVAL;
 
128	}
129
130	rcu_read_lock();
 
 
131
132	tb_id = fib_rule_get_table(rule, arg);
133	tbl = fib_get_table(rule->fr_net, tb_id);
134	if (tbl)
135		err = fib_table_lookup(tbl, &flp->u.ip4,
136				       (struct fib_result *)arg->result,
137				       arg->flags);
138
139	rcu_read_unlock();
140	return err;
141}
142
143INDIRECT_CALLABLE_SCOPE bool fib4_rule_suppress(struct fib_rule *rule,
144						struct fib_lookup_arg *arg)
145{
146	struct fib_result *result = (struct fib_result *) arg->result;
147	struct net_device *dev = NULL;
148
149	if (result->fi) {
150		struct fib_nh_common *nhc = fib_info_nhc(result->fi, 0);
151
152		dev = nhc->nhc_dev;
153	}
154
155	/* do not accept result if the route does
156	 * not meet the required prefix length
157	 */
158	if (result->prefixlen <= rule->suppress_prefixlen)
159		goto suppress_route;
160
161	/* do not accept result if the route uses a device
162	 * belonging to a forbidden interface group
163	 */
164	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
165		goto suppress_route;
166
167	return false;
168
169suppress_route:
170	if (!(arg->flags & FIB_LOOKUP_NOREF))
171		fib_info_put(result->fi);
172	return true;
173}
174
175INDIRECT_CALLABLE_SCOPE int fib4_rule_match(struct fib_rule *rule,
176					    struct flowi *fl, int flags)
177{
178	struct fib4_rule *r = (struct fib4_rule *) rule;
179	struct flowi4 *fl4 = &fl->u.ip4;
180	__be32 daddr = fl4->daddr;
181	__be32 saddr = fl4->saddr;
182
183	if (((saddr ^ r->src) & r->srcmask) ||
184	    ((daddr ^ r->dst) & r->dstmask))
185		return 0;
186
187	if (r->tos && (r->tos != fl4->flowi4_tos))
188		return 0;
189
190	if (rule->ip_proto && (rule->ip_proto != fl4->flowi4_proto))
191		return 0;
192
193	if (fib_rule_port_range_set(&rule->sport_range) &&
194	    !fib_rule_port_inrange(&rule->sport_range, fl4->fl4_sport))
195		return 0;
196
197	if (fib_rule_port_range_set(&rule->dport_range) &&
198	    !fib_rule_port_inrange(&rule->dport_range, fl4->fl4_dport))
199		return 0;
200
201	return 1;
202}
203
204static struct fib_table *fib_empty_table(struct net *net)
205{
206	u32 id = 1;
207
208	while (1) {
209		if (!fib_get_table(net, id))
210			return fib_new_table(net, id);
211
212		if (id++ == RT_TABLE_MAX)
213			break;
214	}
215	return NULL;
216}
217
218static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
219	FRA_GENERIC_POLICY,
220	[FRA_FLOW]	= { .type = NLA_U32 },
221};
222
223static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
224			       struct fib_rule_hdr *frh,
225			       struct nlattr **tb,
226			       struct netlink_ext_ack *extack)
227{
228	struct net *net = sock_net(skb->sk);
229	int err = -EINVAL;
230	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
231
232	if (frh->tos & ~IPTOS_TOS_MASK) {
233		NL_SET_ERR_MSG(extack, "Invalid tos");
234		goto errout;
235	}
236
237	/* split local/main if they are not already split */
238	err = fib_unmerge(net);
239	if (err)
240		goto errout;
241
242	if (rule->table == RT_TABLE_UNSPEC && !rule->l3mdev) {
243		if (rule->action == FR_ACT_TO_TBL) {
244			struct fib_table *table;
245
246			table = fib_empty_table(net);
247			if (!table) {
248				err = -ENOBUFS;
249				goto errout;
250			}
251
252			rule->table = table->tb_id;
253		}
254	}
255
256	if (frh->src_len)
257		rule4->src = nla_get_in_addr(tb[FRA_SRC]);
258
259	if (frh->dst_len)
260		rule4->dst = nla_get_in_addr(tb[FRA_DST]);
261
262#ifdef CONFIG_IP_ROUTE_CLASSID
263	if (tb[FRA_FLOW]) {
264		rule4->tclassid = nla_get_u32(tb[FRA_FLOW]);
265		if (rule4->tclassid)
266			net->ipv4.fib_num_tclassid_users++;
267	}
268#endif
269
270	if (fib_rule_requires_fldissect(rule))
271		net->ipv4.fib_rules_require_fldissect++;
272
273	rule4->src_len = frh->src_len;
274	rule4->srcmask = inet_make_mask(rule4->src_len);
275	rule4->dst_len = frh->dst_len;
276	rule4->dstmask = inet_make_mask(rule4->dst_len);
277	rule4->tos = frh->tos;
278
279	net->ipv4.fib_has_custom_rules = true;
280
281	err = 0;
282errout:
283	return err;
284}
285
286static int fib4_rule_delete(struct fib_rule *rule)
287{
288	struct net *net = rule->fr_net;
289	int err;
 
290
291	/* split local/main if they are not already split */
292	err = fib_unmerge(net);
293	if (err)
294		goto errout;
295
296#ifdef CONFIG_IP_ROUTE_CLASSID
297	if (((struct fib4_rule *)rule)->tclassid)
298		net->ipv4.fib_num_tclassid_users--;
299#endif
300	net->ipv4.fib_has_custom_rules = true;
301
302	if (net->ipv4.fib_rules_require_fldissect &&
303	    fib_rule_requires_fldissect(rule))
304		net->ipv4.fib_rules_require_fldissect--;
305errout:
306	return err;
307}
308
309static int fib4_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
310			     struct nlattr **tb)
311{
312	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
313
314	if (frh->src_len && (rule4->src_len != frh->src_len))
315		return 0;
316
317	if (frh->dst_len && (rule4->dst_len != frh->dst_len))
318		return 0;
319
320	if (frh->tos && (rule4->tos != frh->tos))
321		return 0;
322
323#ifdef CONFIG_IP_ROUTE_CLASSID
324	if (tb[FRA_FLOW] && (rule4->tclassid != nla_get_u32(tb[FRA_FLOW])))
325		return 0;
326#endif
327
328	if (frh->src_len && (rule4->src != nla_get_in_addr(tb[FRA_SRC])))
329		return 0;
330
331	if (frh->dst_len && (rule4->dst != nla_get_in_addr(tb[FRA_DST])))
332		return 0;
333
334	return 1;
335}
336
337static int fib4_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
338			  struct fib_rule_hdr *frh)
339{
340	struct fib4_rule *rule4 = (struct fib4_rule *) rule;
341
342	frh->dst_len = rule4->dst_len;
343	frh->src_len = rule4->src_len;
344	frh->tos = rule4->tos;
345
346	if ((rule4->dst_len &&
347	     nla_put_in_addr(skb, FRA_DST, rule4->dst)) ||
348	    (rule4->src_len &&
349	     nla_put_in_addr(skb, FRA_SRC, rule4->src)))
350		goto nla_put_failure;
351#ifdef CONFIG_IP_ROUTE_CLASSID
352	if (rule4->tclassid &&
353	    nla_put_u32(skb, FRA_FLOW, rule4->tclassid))
354		goto nla_put_failure;
355#endif
356	return 0;
357
358nla_put_failure:
359	return -ENOBUFS;
360}
361
362static size_t fib4_rule_nlmsg_payload(struct fib_rule *rule)
363{
364	return nla_total_size(4) /* dst */
365	       + nla_total_size(4) /* src */
366	       + nla_total_size(4); /* flow */
367}
368
369static void fib4_rule_flush_cache(struct fib_rules_ops *ops)
370{
371	rt_cache_flush(ops->fro_net);
372}
373
374static const struct fib_rules_ops __net_initconst fib4_rules_ops_template = {
375	.family		= AF_INET,
376	.rule_size	= sizeof(struct fib4_rule),
377	.addr_size	= sizeof(u32),
378	.action		= fib4_rule_action,
379	.suppress	= fib4_rule_suppress,
380	.match		= fib4_rule_match,
381	.configure	= fib4_rule_configure,
382	.delete		= fib4_rule_delete,
383	.compare	= fib4_rule_compare,
384	.fill		= fib4_rule_fill,
 
385	.nlmsg_payload	= fib4_rule_nlmsg_payload,
386	.flush_cache	= fib4_rule_flush_cache,
387	.nlgroup	= RTNLGRP_IPV4_RULE,
388	.policy		= fib4_rule_policy,
389	.owner		= THIS_MODULE,
390};
391
392static int fib_default_rules_init(struct fib_rules_ops *ops)
393{
394	int err;
395
396	err = fib_default_rule_add(ops, 0, RT_TABLE_LOCAL, 0);
397	if (err < 0)
398		return err;
399	err = fib_default_rule_add(ops, 0x7FFE, RT_TABLE_MAIN, 0);
400	if (err < 0)
401		return err;
402	err = fib_default_rule_add(ops, 0x7FFF, RT_TABLE_DEFAULT, 0);
403	if (err < 0)
404		return err;
405	return 0;
406}
407
408int __net_init fib4_rules_init(struct net *net)
409{
410	int err;
411	struct fib_rules_ops *ops;
412
413	ops = fib_rules_register(&fib4_rules_ops_template, net);
414	if (IS_ERR(ops))
415		return PTR_ERR(ops);
416
417	err = fib_default_rules_init(ops);
418	if (err < 0)
419		goto fail;
420	net->ipv4.rules_ops = ops;
421	net->ipv4.fib_has_custom_rules = false;
422	net->ipv4.fib_rules_require_fldissect = 0;
423	return 0;
424
425fail:
426	/* also cleans all rules already added */
427	fib_rules_unregister(ops);
428	return err;
429}
430
431void __net_exit fib4_rules_exit(struct net *net)
432{
433	fib_rules_unregister(net->ipv4.rules_ops);
434}