xref: /linux/net/ipv6/fib6_rules.c (revision 1a9239bb4253f9076b5b4b2a1a4e8d7defd77a95)
1 // SPDX-License-Identifier: GPL-2.0-only
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  *
8  * Authors
9  *	Thomas Graf		<tgraf@suug.ch>
10  *	Ville Nuorvala		<vnuorval@tcs.hut.fi>
11  */
12 
13 #include <linux/netdevice.h>
14 #include <linux/notifier.h>
15 #include <linux/export.h>
16 #include <linux/indirect_call_wrapper.h>
17 
18 #include <net/fib_rules.h>
19 #include <net/inet_dscp.h>
20 #include <net/ipv6.h>
21 #include <net/addrconf.h>
22 #include <net/ip6_route.h>
23 #include <net/netlink.h>
24 
25 struct fib6_rule {
26 	struct fib_rule		common;
27 	struct rt6key		src;
28 	struct rt6key		dst;
29 	__be32			flowlabel;
30 	__be32			flowlabel_mask;
31 	dscp_t			dscp;
32 	dscp_t			dscp_mask;
33 	u8			dscp_full:1;	/* DSCP or TOS selector */
34 };
35 
fib6_rule_matchall(const struct fib_rule * rule)36 static bool fib6_rule_matchall(const struct fib_rule *rule)
37 {
38 	struct fib6_rule *r = container_of(rule, struct fib6_rule, common);
39 
40 	if (r->dst.plen || r->src.plen || r->dscp || r->flowlabel_mask)
41 		return false;
42 	return fib_rule_matchall(rule);
43 }
44 
fib6_rule_default(const struct fib_rule * rule)45 bool fib6_rule_default(const struct fib_rule *rule)
46 {
47 	if (!fib6_rule_matchall(rule) || rule->action != FR_ACT_TO_TBL ||
48 	    rule->l3mdev)
49 		return false;
50 	if (rule->table != RT6_TABLE_LOCAL && rule->table != RT6_TABLE_MAIN)
51 		return false;
52 	return true;
53 }
54 EXPORT_SYMBOL_GPL(fib6_rule_default);
55 
fib6_rules_dump(struct net * net,struct notifier_block * nb,struct netlink_ext_ack * extack)56 int fib6_rules_dump(struct net *net, struct notifier_block *nb,
57 		    struct netlink_ext_ack *extack)
58 {
59 	return fib_rules_dump(net, nb, AF_INET6, extack);
60 }
61 
fib6_rules_seq_read(const struct net * net)62 unsigned int fib6_rules_seq_read(const struct net *net)
63 {
64 	return fib_rules_seq_read(net, AF_INET6);
65 }
66 
67 /* called with rcu lock held; no reference taken on fib6_info */
fib6_lookup(struct net * net,int oif,struct flowi6 * fl6,struct fib6_result * res,int flags)68 int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6,
69 		struct fib6_result *res, int flags)
70 {
71 	int err;
72 
73 	if (net->ipv6.fib6_has_custom_rules) {
74 		struct fib_lookup_arg arg = {
75 			.lookup_ptr = fib6_table_lookup,
76 			.lookup_data = &oif,
77 			.result = res,
78 			.flags = FIB_LOOKUP_NOREF,
79 		};
80 
81 		l3mdev_update_flow(net, flowi6_to_flowi(fl6));
82 
83 		err = fib_rules_lookup(net->ipv6.fib6_rules_ops,
84 				       flowi6_to_flowi(fl6), flags, &arg);
85 	} else {
86 		err = fib6_table_lookup(net, net->ipv6.fib6_local_tbl, oif,
87 					fl6, res, flags);
88 		if (err || res->f6i == net->ipv6.fib6_null_entry)
89 			err = fib6_table_lookup(net, net->ipv6.fib6_main_tbl,
90 						oif, fl6, res, flags);
91 	}
92 
93 	return err;
94 }
95 
fib6_rule_lookup(struct net * net,struct flowi6 * fl6,const struct sk_buff * skb,int flags,pol_lookup_t lookup)96 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
97 				   const struct sk_buff *skb,
98 				   int flags, pol_lookup_t lookup)
99 {
100 	if (net->ipv6.fib6_has_custom_rules) {
101 		struct fib6_result res = {};
102 		struct fib_lookup_arg arg = {
103 			.lookup_ptr = lookup,
104 			.lookup_data = skb,
105 			.result = &res,
106 			.flags = FIB_LOOKUP_NOREF,
107 		};
108 
109 		/* update flow if oif or iif point to device enslaved to l3mdev */
110 		l3mdev_update_flow(net, flowi6_to_flowi(fl6));
111 
112 		fib_rules_lookup(net->ipv6.fib6_rules_ops,
113 				 flowi6_to_flowi(fl6), flags, &arg);
114 
115 		if (res.rt6)
116 			return &res.rt6->dst;
117 	} else {
118 		struct rt6_info *rt;
119 
120 		rt = pol_lookup_func(lookup,
121 			     net, net->ipv6.fib6_local_tbl, fl6, skb, flags);
122 		if (rt != net->ipv6.ip6_null_entry && rt->dst.error != -EAGAIN)
123 			return &rt->dst;
124 		ip6_rt_put_flags(rt, flags);
125 		rt = pol_lookup_func(lookup,
126 			     net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
127 		if (rt->dst.error != -EAGAIN)
128 			return &rt->dst;
129 		ip6_rt_put_flags(rt, flags);
130 	}
131 
132 	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
133 		dst_hold(&net->ipv6.ip6_null_entry->dst);
134 	return &net->ipv6.ip6_null_entry->dst;
135 }
136 
fib6_rule_saddr(struct net * net,struct fib_rule * rule,int flags,struct flowi6 * flp6,const struct net_device * dev)137 static int fib6_rule_saddr(struct net *net, struct fib_rule *rule, int flags,
138 			   struct flowi6 *flp6, const struct net_device *dev)
139 {
140 	struct fib6_rule *r = (struct fib6_rule *)rule;
141 
142 	/* If we need to find a source address for this traffic,
143 	 * we check the result if it meets requirement of the rule.
144 	 */
145 	if ((rule->flags & FIB_RULE_FIND_SADDR) &&
146 	    r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
147 		struct in6_addr saddr;
148 
149 		if (ipv6_dev_get_saddr(net, dev, &flp6->daddr,
150 				       rt6_flags2srcprefs(flags), &saddr))
151 			return -EAGAIN;
152 
153 		if (!ipv6_prefix_equal(&saddr, &r->src.addr, r->src.plen))
154 			return -EAGAIN;
155 
156 		flp6->saddr = saddr;
157 	}
158 
159 	return 0;
160 }
161 
fib6_rule_action_alt(struct fib_rule * rule,struct flowi * flp,int flags,struct fib_lookup_arg * arg)162 static int fib6_rule_action_alt(struct fib_rule *rule, struct flowi *flp,
163 				int flags, struct fib_lookup_arg *arg)
164 {
165 	struct fib6_result *res = arg->result;
166 	struct flowi6 *flp6 = &flp->u.ip6;
167 	struct net *net = rule->fr_net;
168 	struct fib6_table *table;
169 	int err, *oif;
170 	u32 tb_id;
171 
172 	switch (rule->action) {
173 	case FR_ACT_TO_TBL:
174 		break;
175 	case FR_ACT_UNREACHABLE:
176 		return -ENETUNREACH;
177 	case FR_ACT_PROHIBIT:
178 		return -EACCES;
179 	case FR_ACT_BLACKHOLE:
180 	default:
181 		return -EINVAL;
182 	}
183 
184 	tb_id = fib_rule_get_table(rule, arg);
185 	table = fib6_get_table(net, tb_id);
186 	if (!table)
187 		return -EAGAIN;
188 
189 	oif = (int *)arg->lookup_data;
190 	err = fib6_table_lookup(net, table, *oif, flp6, res, flags);
191 	if (!err && res->f6i != net->ipv6.fib6_null_entry)
192 		err = fib6_rule_saddr(net, rule, flags, flp6,
193 				      res->nh->fib_nh_dev);
194 	else
195 		err = -EAGAIN;
196 
197 	return err;
198 }
199 
__fib6_rule_action(struct fib_rule * rule,struct flowi * flp,int flags,struct fib_lookup_arg * arg)200 static int __fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
201 			      int flags, struct fib_lookup_arg *arg)
202 {
203 	struct fib6_result *res = arg->result;
204 	struct flowi6 *flp6 = &flp->u.ip6;
205 	struct rt6_info *rt = NULL;
206 	struct fib6_table *table;
207 	struct net *net = rule->fr_net;
208 	pol_lookup_t lookup = arg->lookup_ptr;
209 	int err = 0;
210 	u32 tb_id;
211 
212 	switch (rule->action) {
213 	case FR_ACT_TO_TBL:
214 		break;
215 	case FR_ACT_UNREACHABLE:
216 		err = -ENETUNREACH;
217 		rt = net->ipv6.ip6_null_entry;
218 		goto discard_pkt;
219 	default:
220 	case FR_ACT_BLACKHOLE:
221 		err = -EINVAL;
222 		rt = net->ipv6.ip6_blk_hole_entry;
223 		goto discard_pkt;
224 	case FR_ACT_PROHIBIT:
225 		err = -EACCES;
226 		rt = net->ipv6.ip6_prohibit_entry;
227 		goto discard_pkt;
228 	}
229 
230 	tb_id = fib_rule_get_table(rule, arg);
231 	table = fib6_get_table(net, tb_id);
232 	if (!table) {
233 		err = -EAGAIN;
234 		goto out;
235 	}
236 
237 	rt = pol_lookup_func(lookup,
238 			     net, table, flp6, arg->lookup_data, flags);
239 	if (rt != net->ipv6.ip6_null_entry) {
240 		struct inet6_dev *idev = ip6_dst_idev(&rt->dst);
241 
242 		if (!idev)
243 			goto again;
244 		err = fib6_rule_saddr(net, rule, flags, flp6,
245 				      idev->dev);
246 
247 		if (err == -EAGAIN)
248 			goto again;
249 
250 		err = rt->dst.error;
251 		if (err != -EAGAIN)
252 			goto out;
253 	}
254 again:
255 	ip6_rt_put_flags(rt, flags);
256 	err = -EAGAIN;
257 	rt = NULL;
258 	goto out;
259 
260 discard_pkt:
261 	if (!(flags & RT6_LOOKUP_F_DST_NOREF))
262 		dst_hold(&rt->dst);
263 out:
264 	res->rt6 = rt;
265 	return err;
266 }
267 
fib6_rule_action(struct fib_rule * rule,struct flowi * flp,int flags,struct fib_lookup_arg * arg)268 INDIRECT_CALLABLE_SCOPE int fib6_rule_action(struct fib_rule *rule,
269 					     struct flowi *flp, int flags,
270 					     struct fib_lookup_arg *arg)
271 {
272 	if (arg->lookup_ptr == fib6_table_lookup)
273 		return fib6_rule_action_alt(rule, flp, flags, arg);
274 
275 	return __fib6_rule_action(rule, flp, flags, arg);
276 }
277 
fib6_rule_suppress(struct fib_rule * rule,int flags,struct fib_lookup_arg * arg)278 INDIRECT_CALLABLE_SCOPE bool fib6_rule_suppress(struct fib_rule *rule,
279 						int flags,
280 						struct fib_lookup_arg *arg)
281 {
282 	struct fib6_result *res = arg->result;
283 	struct rt6_info *rt = res->rt6;
284 	struct net_device *dev = NULL;
285 
286 	if (!rt)
287 		return false;
288 
289 	if (rt->rt6i_idev)
290 		dev = rt->rt6i_idev->dev;
291 
292 	/* do not accept result if the route does
293 	 * not meet the required prefix length
294 	 */
295 	if (rt->rt6i_dst.plen <= rule->suppress_prefixlen)
296 		goto suppress_route;
297 
298 	/* do not accept result if the route uses a device
299 	 * belonging to a forbidden interface group
300 	 */
301 	if (rule->suppress_ifgroup != -1 && dev && dev->group == rule->suppress_ifgroup)
302 		goto suppress_route;
303 
304 	return false;
305 
306 suppress_route:
307 	ip6_rt_put_flags(rt, flags);
308 	return true;
309 }
310 
fib6_rule_match(struct fib_rule * rule,struct flowi * fl,int flags)311 INDIRECT_CALLABLE_SCOPE int fib6_rule_match(struct fib_rule *rule,
312 					    struct flowi *fl, int flags)
313 {
314 	struct fib6_rule *r = (struct fib6_rule *) rule;
315 	struct flowi6 *fl6 = &fl->u.ip6;
316 
317 	if (r->dst.plen &&
318 	    !ipv6_prefix_equal(&fl6->daddr, &r->dst.addr, r->dst.plen))
319 		return 0;
320 
321 	/*
322 	 * If FIB_RULE_FIND_SADDR is set and we do not have a
323 	 * source address for the traffic, we defer check for
324 	 * source address.
325 	 */
326 	if (r->src.plen) {
327 		if (flags & RT6_LOOKUP_F_HAS_SADDR) {
328 			if (!ipv6_prefix_equal(&fl6->saddr, &r->src.addr,
329 					       r->src.plen))
330 				return 0;
331 		} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
332 			return 0;
333 	}
334 
335 	if ((r->dscp ^ ip6_dscp(fl6->flowlabel)) & r->dscp_mask)
336 		return 0;
337 
338 	if ((r->flowlabel ^ flowi6_get_flowlabel(fl6)) & r->flowlabel_mask)
339 		return 0;
340 
341 	if (rule->ip_proto && (rule->ip_proto != fl6->flowi6_proto))
342 		return 0;
343 
344 	if (!fib_rule_port_match(&rule->sport_range, rule->sport_mask,
345 				 fl6->fl6_sport))
346 		return 0;
347 
348 	if (!fib_rule_port_match(&rule->dport_range, rule->dport_mask,
349 				 fl6->fl6_dport))
350 		return 0;
351 
352 	return 1;
353 }
354 
fib6_nl2rule_dscp(const struct nlattr * nla,struct fib6_rule * rule6,struct netlink_ext_ack * extack)355 static int fib6_nl2rule_dscp(const struct nlattr *nla, struct fib6_rule *rule6,
356 			     struct netlink_ext_ack *extack)
357 {
358 	if (rule6->dscp) {
359 		NL_SET_ERR_MSG(extack, "Cannot specify both TOS and DSCP");
360 		return -EINVAL;
361 	}
362 
363 	rule6->dscp = inet_dsfield_to_dscp(nla_get_u8(nla) << 2);
364 	rule6->dscp_mask = inet_dsfield_to_dscp(INET_DSCP_MASK);
365 	rule6->dscp_full = true;
366 
367 	return 0;
368 }
369 
fib6_nl2rule_dscp_mask(const struct nlattr * nla,struct fib6_rule * rule6,struct netlink_ext_ack * extack)370 static int fib6_nl2rule_dscp_mask(const struct nlattr *nla,
371 				  struct fib6_rule *rule6,
372 				  struct netlink_ext_ack *extack)
373 {
374 	dscp_t dscp_mask;
375 
376 	if (!rule6->dscp_full) {
377 		NL_SET_ERR_MSG_ATTR(extack, nla,
378 				    "Cannot specify DSCP mask without DSCP value");
379 		return -EINVAL;
380 	}
381 
382 	dscp_mask = inet_dsfield_to_dscp(nla_get_u8(nla) << 2);
383 	if (rule6->dscp & ~dscp_mask) {
384 		NL_SET_ERR_MSG_ATTR(extack, nla, "Invalid DSCP mask");
385 		return -EINVAL;
386 	}
387 
388 	rule6->dscp_mask = dscp_mask;
389 
390 	return 0;
391 }
392 
fib6_nl2rule_flowlabel(struct nlattr ** tb,struct fib6_rule * rule6,struct netlink_ext_ack * extack)393 static int fib6_nl2rule_flowlabel(struct nlattr **tb, struct fib6_rule *rule6,
394 				  struct netlink_ext_ack *extack)
395 {
396 	__be32 flowlabel, flowlabel_mask;
397 
398 	if (NL_REQ_ATTR_CHECK(extack, NULL, tb, FRA_FLOWLABEL) ||
399 	    NL_REQ_ATTR_CHECK(extack, NULL, tb, FRA_FLOWLABEL_MASK))
400 		return -EINVAL;
401 
402 	flowlabel = nla_get_be32(tb[FRA_FLOWLABEL]);
403 	flowlabel_mask = nla_get_be32(tb[FRA_FLOWLABEL_MASK]);
404 
405 	if (flowlabel_mask & ~IPV6_FLOWLABEL_MASK) {
406 		NL_SET_ERR_MSG_ATTR(extack, tb[FRA_FLOWLABEL_MASK],
407 				    "Invalid flow label mask");
408 		return -EINVAL;
409 	}
410 
411 	if (flowlabel & ~flowlabel_mask) {
412 		NL_SET_ERR_MSG(extack, "Flow label and mask do not match");
413 		return -EINVAL;
414 	}
415 
416 	rule6->flowlabel = flowlabel;
417 	rule6->flowlabel_mask = flowlabel_mask;
418 
419 	return 0;
420 }
421 
fib6_rule_configure(struct fib_rule * rule,struct sk_buff * skb,struct fib_rule_hdr * frh,struct nlattr ** tb,struct netlink_ext_ack * extack)422 static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
423 			       struct fib_rule_hdr *frh,
424 			       struct nlattr **tb,
425 			       struct netlink_ext_ack *extack)
426 {
427 	struct fib6_rule *rule6 = (struct fib6_rule *)rule;
428 	struct net *net = rule->fr_net;
429 	int err = -EINVAL;
430 
431 	if (!inet_validate_dscp(frh->tos)) {
432 		NL_SET_ERR_MSG(extack,
433 			       "Invalid dsfield (tos): ECN bits must be 0");
434 		goto errout;
435 	}
436 	rule6->dscp = inet_dsfield_to_dscp(frh->tos);
437 	rule6->dscp_mask = frh->tos ? inet_dsfield_to_dscp(INET_DSCP_MASK) : 0;
438 
439 	if (tb[FRA_DSCP] && fib6_nl2rule_dscp(tb[FRA_DSCP], rule6, extack) < 0)
440 		goto errout;
441 
442 	if (tb[FRA_DSCP_MASK] &&
443 	    fib6_nl2rule_dscp_mask(tb[FRA_DSCP_MASK], rule6, extack) < 0)
444 		goto errout;
445 
446 	if ((tb[FRA_FLOWLABEL] || tb[FRA_FLOWLABEL_MASK]) &&
447 	    fib6_nl2rule_flowlabel(tb, rule6, extack) < 0)
448 		goto errout;
449 
450 	if (rule->action == FR_ACT_TO_TBL && !rule->l3mdev) {
451 		if (rule->table == RT6_TABLE_UNSPEC) {
452 			NL_SET_ERR_MSG(extack, "Invalid table");
453 			goto errout;
454 		}
455 
456 		if (fib6_new_table(net, rule->table) == NULL) {
457 			err = -ENOBUFS;
458 			goto errout;
459 		}
460 	}
461 
462 	if (frh->src_len)
463 		rule6->src.addr = nla_get_in6_addr(tb[FRA_SRC]);
464 
465 	if (frh->dst_len)
466 		rule6->dst.addr = nla_get_in6_addr(tb[FRA_DST]);
467 
468 	rule6->src.plen = frh->src_len;
469 	rule6->dst.plen = frh->dst_len;
470 
471 	if (fib_rule_requires_fldissect(rule))
472 		net->ipv6.fib6_rules_require_fldissect++;
473 
474 	net->ipv6.fib6_has_custom_rules = true;
475 	err = 0;
476 errout:
477 	return err;
478 }
479 
fib6_rule_delete(struct fib_rule * rule)480 static int fib6_rule_delete(struct fib_rule *rule)
481 {
482 	struct net *net = rule->fr_net;
483 
484 	if (net->ipv6.fib6_rules_require_fldissect &&
485 	    fib_rule_requires_fldissect(rule))
486 		net->ipv6.fib6_rules_require_fldissect--;
487 
488 	return 0;
489 }
490 
fib6_rule_compare(struct fib_rule * rule,struct fib_rule_hdr * frh,struct nlattr ** tb)491 static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
492 			     struct nlattr **tb)
493 {
494 	struct fib6_rule *rule6 = (struct fib6_rule *) rule;
495 
496 	if (frh->src_len && (rule6->src.plen != frh->src_len))
497 		return 0;
498 
499 	if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
500 		return 0;
501 
502 	if (frh->tos &&
503 	    (rule6->dscp_full ||
504 	     inet_dscp_to_dsfield(rule6->dscp) != frh->tos))
505 		return 0;
506 
507 	if (tb[FRA_DSCP]) {
508 		dscp_t dscp;
509 
510 		dscp = inet_dsfield_to_dscp(nla_get_u8(tb[FRA_DSCP]) << 2);
511 		if (!rule6->dscp_full || rule6->dscp != dscp)
512 			return 0;
513 	}
514 
515 	if (tb[FRA_DSCP_MASK]) {
516 		dscp_t dscp_mask;
517 
518 		dscp_mask = inet_dsfield_to_dscp(nla_get_u8(tb[FRA_DSCP_MASK]) << 2);
519 		if (!rule6->dscp_full || rule6->dscp_mask != dscp_mask)
520 			return 0;
521 	}
522 
523 	if (tb[FRA_FLOWLABEL] &&
524 	    nla_get_be32(tb[FRA_FLOWLABEL]) != rule6->flowlabel)
525 		return 0;
526 
527 	if (tb[FRA_FLOWLABEL_MASK] &&
528 	    nla_get_be32(tb[FRA_FLOWLABEL_MASK]) != rule6->flowlabel_mask)
529 		return 0;
530 
531 	if (frh->src_len &&
532 	    nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
533 		return 0;
534 
535 	if (frh->dst_len &&
536 	    nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
537 		return 0;
538 
539 	return 1;
540 }
541 
fib6_rule_fill(struct fib_rule * rule,struct sk_buff * skb,struct fib_rule_hdr * frh)542 static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
543 			  struct fib_rule_hdr *frh)
544 {
545 	struct fib6_rule *rule6 = (struct fib6_rule *) rule;
546 
547 	frh->dst_len = rule6->dst.plen;
548 	frh->src_len = rule6->src.plen;
549 
550 	if (rule6->dscp_full) {
551 		frh->tos = 0;
552 		if (nla_put_u8(skb, FRA_DSCP,
553 			       inet_dscp_to_dsfield(rule6->dscp) >> 2) ||
554 		    nla_put_u8(skb, FRA_DSCP_MASK,
555 			       inet_dscp_to_dsfield(rule6->dscp_mask) >> 2))
556 			goto nla_put_failure;
557 	} else {
558 		frh->tos = inet_dscp_to_dsfield(rule6->dscp);
559 	}
560 
561 	if (rule6->flowlabel_mask &&
562 	    (nla_put_be32(skb, FRA_FLOWLABEL, rule6->flowlabel) ||
563 	     nla_put_be32(skb, FRA_FLOWLABEL_MASK, rule6->flowlabel_mask)))
564 		goto nla_put_failure;
565 
566 	if ((rule6->dst.plen &&
567 	     nla_put_in6_addr(skb, FRA_DST, &rule6->dst.addr)) ||
568 	    (rule6->src.plen &&
569 	     nla_put_in6_addr(skb, FRA_SRC, &rule6->src.addr)))
570 		goto nla_put_failure;
571 	return 0;
572 
573 nla_put_failure:
574 	return -ENOBUFS;
575 }
576 
fib6_rule_nlmsg_payload(struct fib_rule * rule)577 static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
578 {
579 	return nla_total_size(16) /* dst */
580 	       + nla_total_size(16) /* src */
581 	       + nla_total_size(1) /* dscp */
582 	       + nla_total_size(1) /* dscp mask */
583 	       + nla_total_size(4) /* flowlabel */
584 	       + nla_total_size(4); /* flowlabel mask */
585 }
586 
fib6_rule_flush_cache(struct fib_rules_ops * ops)587 static void fib6_rule_flush_cache(struct fib_rules_ops *ops)
588 {
589 	rt_genid_bump_ipv6(ops->fro_net);
590 }
591 
592 static const struct fib_rules_ops __net_initconst fib6_rules_ops_template = {
593 	.family			= AF_INET6,
594 	.rule_size		= sizeof(struct fib6_rule),
595 	.addr_size		= sizeof(struct in6_addr),
596 	.action			= fib6_rule_action,
597 	.match			= fib6_rule_match,
598 	.suppress		= fib6_rule_suppress,
599 	.configure		= fib6_rule_configure,
600 	.delete			= fib6_rule_delete,
601 	.compare		= fib6_rule_compare,
602 	.fill			= fib6_rule_fill,
603 	.nlmsg_payload		= fib6_rule_nlmsg_payload,
604 	.flush_cache		= fib6_rule_flush_cache,
605 	.nlgroup		= RTNLGRP_IPV6_RULE,
606 	.owner			= THIS_MODULE,
607 	.fro_net		= &init_net,
608 };
609 
fib6_rules_net_init(struct net * net)610 static int __net_init fib6_rules_net_init(struct net *net)
611 {
612 	struct fib_rules_ops *ops;
613 	int err;
614 
615 	ops = fib_rules_register(&fib6_rules_ops_template, net);
616 	if (IS_ERR(ops))
617 		return PTR_ERR(ops);
618 
619 	err = fib_default_rule_add(ops, 0, RT6_TABLE_LOCAL);
620 	if (err)
621 		goto out_fib6_rules_ops;
622 
623 	err = fib_default_rule_add(ops, 0x7FFE, RT6_TABLE_MAIN);
624 	if (err)
625 		goto out_fib6_rules_ops;
626 
627 	net->ipv6.fib6_rules_ops = ops;
628 	net->ipv6.fib6_rules_require_fldissect = 0;
629 out:
630 	return err;
631 
632 out_fib6_rules_ops:
633 	fib_rules_unregister(ops);
634 	goto out;
635 }
636 
fib6_rules_net_exit_batch(struct list_head * net_list)637 static void __net_exit fib6_rules_net_exit_batch(struct list_head *net_list)
638 {
639 	struct net *net;
640 
641 	rtnl_lock();
642 	list_for_each_entry(net, net_list, exit_list) {
643 		fib_rules_unregister(net->ipv6.fib6_rules_ops);
644 		cond_resched();
645 	}
646 	rtnl_unlock();
647 }
648 
649 static struct pernet_operations fib6_rules_net_ops = {
650 	.init = fib6_rules_net_init,
651 	.exit_batch = fib6_rules_net_exit_batch,
652 };
653 
fib6_rules_init(void)654 int __init fib6_rules_init(void)
655 {
656 	return register_pernet_subsys(&fib6_rules_net_ops);
657 }
658 
659 
fib6_rules_cleanup(void)660 void fib6_rules_cleanup(void)
661 {
662 	unregister_pernet_subsys(&fib6_rules_net_ops);
663 }
664