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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * IPv6 Address Label subsystem
4 * for the IPv6 "Default" Source Address Selection
5 *
6 * Copyright (C)2007 USAGI/WIDE Project
7 */
8/*
9 * Author:
10 * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
11 */
12
13#include <linux/kernel.h>
14#include <linux/list.h>
15#include <linux/rcupdate.h>
16#include <linux/in6.h>
17#include <linux/slab.h>
18#include <net/addrconf.h>
19#include <linux/if_addrlabel.h>
20#include <linux/netlink.h>
21#include <linux/rtnetlink.h>
22
23#if 0
24#define ADDRLABEL(x...) printk(x)
25#else
26#define ADDRLABEL(x...) do { ; } while (0)
27#endif
28
29/*
30 * Policy Table
31 */
32struct ip6addrlbl_entry {
33 struct in6_addr prefix;
34 int prefixlen;
35 int ifindex;
36 int addrtype;
37 u32 label;
38 struct hlist_node list;
39 struct rcu_head rcu;
40};
41
42/*
43 * Default policy table (RFC6724 + extensions)
44 *
45 * prefix addr_type label
46 * -------------------------------------------------------------------------
47 * ::1/128 LOOPBACK 0
48 * ::/0 N/A 1
49 * 2002::/16 N/A 2
50 * ::/96 COMPATv4 3
51 * ::ffff:0:0/96 V4MAPPED 4
52 * fc00::/7 N/A 5 ULA (RFC 4193)
53 * 2001::/32 N/A 6 Teredo (RFC 4380)
54 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
55 * fec0::/10 N/A 11 Site-local
56 * (deprecated by RFC3879)
57 * 3ffe::/16 N/A 12 6bone
58 *
59 * Note: 0xffffffff is used if we do not have any policies.
60 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
61 */
62
63#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
64
65static const __net_initconst struct ip6addrlbl_init_table
66{
67 const struct in6_addr *prefix;
68 int prefixlen;
69 u32 label;
70} ip6addrlbl_init_table[] = {
71 { /* ::/0 */
72 .prefix = &in6addr_any,
73 .label = 1,
74 }, { /* fc00::/7 */
75 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
76 .prefixlen = 7,
77 .label = 5,
78 }, { /* fec0::/10 */
79 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
80 .prefixlen = 10,
81 .label = 11,
82 }, { /* 2002::/16 */
83 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
84 .prefixlen = 16,
85 .label = 2,
86 }, { /* 3ffe::/16 */
87 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
88 .prefixlen = 16,
89 .label = 12,
90 }, { /* 2001::/32 */
91 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
92 .prefixlen = 32,
93 .label = 6,
94 }, { /* 2001:10::/28 */
95 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
96 .prefixlen = 28,
97 .label = 7,
98 }, { /* ::ffff:0:0 */
99 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
100 .prefixlen = 96,
101 .label = 4,
102 }, { /* ::/96 */
103 .prefix = &in6addr_any,
104 .prefixlen = 96,
105 .label = 3,
106 }, { /* ::1/128 */
107 .prefix = &in6addr_loopback,
108 .prefixlen = 128,
109 .label = 0,
110 }
111};
112
113/* Find label */
114static bool __ip6addrlbl_match(const struct ip6addrlbl_entry *p,
115 const struct in6_addr *addr,
116 int addrtype, int ifindex)
117{
118 if (p->ifindex && p->ifindex != ifindex)
119 return false;
120 if (p->addrtype && p->addrtype != addrtype)
121 return false;
122 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
123 return false;
124 return true;
125}
126
127static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
128 const struct in6_addr *addr,
129 int type, int ifindex)
130{
131 struct ip6addrlbl_entry *p;
132
133 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
134 if (__ip6addrlbl_match(p, addr, type, ifindex))
135 return p;
136 }
137 return NULL;
138}
139
140u32 ipv6_addr_label(struct net *net,
141 const struct in6_addr *addr, int type, int ifindex)
142{
143 u32 label;
144 struct ip6addrlbl_entry *p;
145
146 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
147
148 rcu_read_lock();
149 p = __ipv6_addr_label(net, addr, type, ifindex);
150 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
151 rcu_read_unlock();
152
153 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
154 __func__, addr, type, ifindex, label);
155
156 return label;
157}
158
159/* allocate one entry */
160static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
161 int prefixlen, int ifindex,
162 u32 label)
163{
164 struct ip6addrlbl_entry *newp;
165 int addrtype;
166
167 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
168 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
169
170 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
171
172 switch (addrtype) {
173 case IPV6_ADDR_MAPPED:
174 if (prefixlen > 96)
175 return ERR_PTR(-EINVAL);
176 if (prefixlen < 96)
177 addrtype = 0;
178 break;
179 case IPV6_ADDR_COMPATv4:
180 if (prefixlen != 96)
181 addrtype = 0;
182 break;
183 case IPV6_ADDR_LOOPBACK:
184 if (prefixlen != 128)
185 addrtype = 0;
186 break;
187 }
188
189 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
190 if (!newp)
191 return ERR_PTR(-ENOMEM);
192
193 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
194 newp->prefixlen = prefixlen;
195 newp->ifindex = ifindex;
196 newp->addrtype = addrtype;
197 newp->label = label;
198 INIT_HLIST_NODE(&newp->list);
199 return newp;
200}
201
202/* add a label */
203static int __ip6addrlbl_add(struct net *net, struct ip6addrlbl_entry *newp,
204 int replace)
205{
206 struct ip6addrlbl_entry *last = NULL, *p = NULL;
207 struct hlist_node *n;
208 int ret = 0;
209
210 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
211 replace);
212
213 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
214 if (p->prefixlen == newp->prefixlen &&
215 p->ifindex == newp->ifindex &&
216 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
217 if (!replace) {
218 ret = -EEXIST;
219 goto out;
220 }
221 hlist_replace_rcu(&p->list, &newp->list);
222 kfree_rcu(p, rcu);
223 goto out;
224 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
225 (p->prefixlen < newp->prefixlen)) {
226 hlist_add_before_rcu(&newp->list, &p->list);
227 goto out;
228 }
229 last = p;
230 }
231 if (last)
232 hlist_add_behind_rcu(&newp->list, &last->list);
233 else
234 hlist_add_head_rcu(&newp->list, &net->ipv6.ip6addrlbl_table.head);
235out:
236 if (!ret)
237 net->ipv6.ip6addrlbl_table.seq++;
238 return ret;
239}
240
241/* add a label */
242static int ip6addrlbl_add(struct net *net,
243 const struct in6_addr *prefix, int prefixlen,
244 int ifindex, u32 label, int replace)
245{
246 struct ip6addrlbl_entry *newp;
247 int ret = 0;
248
249 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
250 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
251 replace);
252
253 newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
254 if (IS_ERR(newp))
255 return PTR_ERR(newp);
256 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
257 ret = __ip6addrlbl_add(net, newp, replace);
258 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
259 if (ret)
260 kfree(newp);
261 return ret;
262}
263
264/* remove a label */
265static int __ip6addrlbl_del(struct net *net,
266 const struct in6_addr *prefix, int prefixlen,
267 int ifindex)
268{
269 struct ip6addrlbl_entry *p = NULL;
270 struct hlist_node *n;
271 int ret = -ESRCH;
272
273 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
274 __func__, prefix, prefixlen, ifindex);
275
276 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
277 if (p->prefixlen == prefixlen &&
278 p->ifindex == ifindex &&
279 ipv6_addr_equal(&p->prefix, prefix)) {
280 hlist_del_rcu(&p->list);
281 kfree_rcu(p, rcu);
282 ret = 0;
283 break;
284 }
285 }
286 return ret;
287}
288
289static int ip6addrlbl_del(struct net *net,
290 const struct in6_addr *prefix, int prefixlen,
291 int ifindex)
292{
293 struct in6_addr prefix_buf;
294 int ret;
295
296 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
297 __func__, prefix, prefixlen, ifindex);
298
299 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
300 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
301 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
302 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
303 return ret;
304}
305
306/* add default label */
307static int __net_init ip6addrlbl_net_init(struct net *net)
308{
309 struct ip6addrlbl_entry *p = NULL;
310 struct hlist_node *n;
311 int err;
312 int i;
313
314 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
315
316 spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
317 INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
318
319 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
320 err = ip6addrlbl_add(net,
321 ip6addrlbl_init_table[i].prefix,
322 ip6addrlbl_init_table[i].prefixlen,
323 0,
324 ip6addrlbl_init_table[i].label, 0);
325 if (err)
326 goto err_ip6addrlbl_add;
327 }
328 return 0;
329
330err_ip6addrlbl_add:
331 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
332 hlist_del_rcu(&p->list);
333 kfree_rcu(p, rcu);
334 }
335 return err;
336}
337
338static void __net_exit ip6addrlbl_net_exit(struct net *net)
339{
340 struct ip6addrlbl_entry *p = NULL;
341 struct hlist_node *n;
342
343 /* Remove all labels belonging to the exiting net */
344 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
345 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
346 hlist_del_rcu(&p->list);
347 kfree_rcu(p, rcu);
348 }
349 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
350}
351
352static struct pernet_operations ipv6_addr_label_ops = {
353 .init = ip6addrlbl_net_init,
354 .exit = ip6addrlbl_net_exit,
355};
356
357int __init ipv6_addr_label_init(void)
358{
359 return register_pernet_subsys(&ipv6_addr_label_ops);
360}
361
362void ipv6_addr_label_cleanup(void)
363{
364 unregister_pernet_subsys(&ipv6_addr_label_ops);
365}
366
367static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
368 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
369 [IFAL_LABEL] = { .len = sizeof(u32), },
370};
371
372static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
373{
374
375 struct net_device *dev;
376
377 rcu_read_lock();
378 dev = dev_get_by_index_rcu(net, ifindex);
379 rcu_read_unlock();
380
381 return dev != NULL;
382}
383
384static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
385 struct netlink_ext_ack *extack)
386{
387 struct net *net = sock_net(skb->sk);
388 struct ifaddrlblmsg *ifal;
389 struct nlattr *tb[IFAL_MAX+1];
390 struct in6_addr *pfx;
391 u32 label;
392 int err = 0;
393
394 err = nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb, IFAL_MAX,
395 ifal_policy, extack);
396 if (err < 0)
397 return err;
398
399 ifal = nlmsg_data(nlh);
400
401 if (ifal->ifal_family != AF_INET6 ||
402 ifal->ifal_prefixlen > 128)
403 return -EINVAL;
404
405 if (!tb[IFAL_ADDRESS])
406 return -EINVAL;
407 pfx = nla_data(tb[IFAL_ADDRESS]);
408
409 if (!tb[IFAL_LABEL])
410 return -EINVAL;
411 label = nla_get_u32(tb[IFAL_LABEL]);
412 if (label == IPV6_ADDR_LABEL_DEFAULT)
413 return -EINVAL;
414
415 switch (nlh->nlmsg_type) {
416 case RTM_NEWADDRLABEL:
417 if (ifal->ifal_index &&
418 !addrlbl_ifindex_exists(net, ifal->ifal_index))
419 return -EINVAL;
420
421 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
422 ifal->ifal_index, label,
423 nlh->nlmsg_flags & NLM_F_REPLACE);
424 break;
425 case RTM_DELADDRLABEL:
426 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
427 ifal->ifal_index);
428 break;
429 default:
430 err = -EOPNOTSUPP;
431 }
432 return err;
433}
434
435static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
436 int prefixlen, int ifindex, u32 lseq)
437{
438 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
439 ifal->ifal_family = AF_INET6;
440 ifal->ifal_prefixlen = prefixlen;
441 ifal->ifal_flags = 0;
442 ifal->ifal_index = ifindex;
443 ifal->ifal_seq = lseq;
444};
445
446static int ip6addrlbl_fill(struct sk_buff *skb,
447 struct ip6addrlbl_entry *p,
448 u32 lseq,
449 u32 portid, u32 seq, int event,
450 unsigned int flags)
451{
452 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
453 sizeof(struct ifaddrlblmsg), flags);
454 if (!nlh)
455 return -EMSGSIZE;
456
457 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
458
459 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
460 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
461 nlmsg_cancel(skb, nlh);
462 return -EMSGSIZE;
463 }
464
465 nlmsg_end(skb, nlh);
466 return 0;
467}
468
469static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
470 struct netlink_ext_ack *extack)
471{
472 struct ifaddrlblmsg *ifal;
473
474 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
475 NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
476 return -EINVAL;
477 }
478
479 ifal = nlmsg_data(nlh);
480 if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
481 ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
482 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
483 return -EINVAL;
484 }
485
486 if (nlmsg_attrlen(nlh, sizeof(*ifal))) {
487 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header for address label dump request");
488 return -EINVAL;
489 }
490
491 return 0;
492}
493
494static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
495{
496 const struct nlmsghdr *nlh = cb->nlh;
497 struct net *net = sock_net(skb->sk);
498 struct ip6addrlbl_entry *p;
499 int idx = 0, s_idx = cb->args[0];
500 int err;
501
502 if (cb->strict_check) {
503 err = ip6addrlbl_valid_dump_req(nlh, cb->extack);
504 if (err < 0)
505 return err;
506 }
507
508 rcu_read_lock();
509 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
510 if (idx >= s_idx) {
511 err = ip6addrlbl_fill(skb, p,
512 net->ipv6.ip6addrlbl_table.seq,
513 NETLINK_CB(cb->skb).portid,
514 nlh->nlmsg_seq,
515 RTM_NEWADDRLABEL,
516 NLM_F_MULTI);
517 if (err < 0)
518 break;
519 }
520 idx++;
521 }
522 rcu_read_unlock();
523 cb->args[0] = idx;
524 return skb->len;
525}
526
527static inline int ip6addrlbl_msgsize(void)
528{
529 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
530 + nla_total_size(16) /* IFAL_ADDRESS */
531 + nla_total_size(4); /* IFAL_LABEL */
532}
533
534static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
535 const struct nlmsghdr *nlh,
536 struct nlattr **tb,
537 struct netlink_ext_ack *extack)
538{
539 struct ifaddrlblmsg *ifal;
540 int i, err;
541
542 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
543 NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
544 return -EINVAL;
545 }
546
547 if (!netlink_strict_get_check(skb))
548 return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
549 IFAL_MAX, ifal_policy, extack);
550
551 ifal = nlmsg_data(nlh);
552 if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
553 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
554 return -EINVAL;
555 }
556
557 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifal), tb, IFAL_MAX,
558 ifal_policy, extack);
559 if (err)
560 return err;
561
562 for (i = 0; i <= IFAL_MAX; i++) {
563 if (!tb[i])
564 continue;
565
566 switch (i) {
567 case IFAL_ADDRESS:
568 break;
569 default:
570 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in addrlabel get request");
571 return -EINVAL;
572 }
573 }
574
575 return 0;
576}
577
578static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
579 struct netlink_ext_ack *extack)
580{
581 struct net *net = sock_net(in_skb->sk);
582 struct ifaddrlblmsg *ifal;
583 struct nlattr *tb[IFAL_MAX+1];
584 struct in6_addr *addr;
585 u32 lseq;
586 int err = 0;
587 struct ip6addrlbl_entry *p;
588 struct sk_buff *skb;
589
590 err = ip6addrlbl_valid_get_req(in_skb, nlh, tb, extack);
591 if (err < 0)
592 return err;
593
594 ifal = nlmsg_data(nlh);
595
596 if (ifal->ifal_family != AF_INET6 ||
597 ifal->ifal_prefixlen != 128)
598 return -EINVAL;
599
600 if (ifal->ifal_index &&
601 !addrlbl_ifindex_exists(net, ifal->ifal_index))
602 return -EINVAL;
603
604 if (!tb[IFAL_ADDRESS])
605 return -EINVAL;
606 addr = nla_data(tb[IFAL_ADDRESS]);
607
608 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
609 if (!skb)
610 return -ENOBUFS;
611
612 err = -ESRCH;
613
614 rcu_read_lock();
615 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
616 lseq = net->ipv6.ip6addrlbl_table.seq;
617 if (p)
618 err = ip6addrlbl_fill(skb, p, lseq,
619 NETLINK_CB(in_skb).portid,
620 nlh->nlmsg_seq,
621 RTM_NEWADDRLABEL, 0);
622 rcu_read_unlock();
623
624 if (err < 0) {
625 WARN_ON(err == -EMSGSIZE);
626 kfree_skb(skb);
627 } else {
628 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
629 }
630 return err;
631}
632
633int __init ipv6_addr_label_rtnl_register(void)
634{
635 int ret;
636
637 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDRLABEL,
638 ip6addrlbl_newdel,
639 NULL, RTNL_FLAG_DOIT_UNLOCKED);
640 if (ret < 0)
641 return ret;
642 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDRLABEL,
643 ip6addrlbl_newdel,
644 NULL, RTNL_FLAG_DOIT_UNLOCKED);
645 if (ret < 0)
646 return ret;
647 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDRLABEL,
648 ip6addrlbl_get,
649 ip6addrlbl_dump, RTNL_FLAG_DOIT_UNLOCKED);
650 return ret;
651}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * IPv6 Address Label subsystem
4 * for the IPv6 "Default" Source Address Selection
5 *
6 * Copyright (C)2007 USAGI/WIDE Project
7 */
8/*
9 * Author:
10 * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
11 */
12
13#include <linux/kernel.h>
14#include <linux/list.h>
15#include <linux/rcupdate.h>
16#include <linux/in6.h>
17#include <linux/slab.h>
18#include <net/addrconf.h>
19#include <linux/if_addrlabel.h>
20#include <linux/netlink.h>
21#include <linux/rtnetlink.h>
22
23#if 0
24#define ADDRLABEL(x...) printk(x)
25#else
26#define ADDRLABEL(x...) do { ; } while (0)
27#endif
28
29/*
30 * Policy Table
31 */
32struct ip6addrlbl_entry {
33 struct in6_addr prefix;
34 int prefixlen;
35 int ifindex;
36 int addrtype;
37 u32 label;
38 struct hlist_node list;
39 struct rcu_head rcu;
40};
41
42/*
43 * Default policy table (RFC6724 + extensions)
44 *
45 * prefix addr_type label
46 * -------------------------------------------------------------------------
47 * ::1/128 LOOPBACK 0
48 * ::/0 N/A 1
49 * 2002::/16 N/A 2
50 * ::/96 COMPATv4 3
51 * ::ffff:0:0/96 V4MAPPED 4
52 * fc00::/7 N/A 5 ULA (RFC 4193)
53 * 2001::/32 N/A 6 Teredo (RFC 4380)
54 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
55 * fec0::/10 N/A 11 Site-local
56 * (deprecated by RFC3879)
57 * 3ffe::/16 N/A 12 6bone
58 *
59 * Note: 0xffffffff is used if we do not have any policies.
60 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
61 */
62
63#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
64
65static const __net_initconst struct ip6addrlbl_init_table
66{
67 const struct in6_addr *prefix;
68 int prefixlen;
69 u32 label;
70} ip6addrlbl_init_table[] = {
71 { /* ::/0 */
72 .prefix = &in6addr_any,
73 .label = 1,
74 }, { /* fc00::/7 */
75 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
76 .prefixlen = 7,
77 .label = 5,
78 }, { /* fec0::/10 */
79 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
80 .prefixlen = 10,
81 .label = 11,
82 }, { /* 2002::/16 */
83 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
84 .prefixlen = 16,
85 .label = 2,
86 }, { /* 3ffe::/16 */
87 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
88 .prefixlen = 16,
89 .label = 12,
90 }, { /* 2001::/32 */
91 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
92 .prefixlen = 32,
93 .label = 6,
94 }, { /* 2001:10::/28 */
95 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
96 .prefixlen = 28,
97 .label = 7,
98 }, { /* ::ffff:0:0 */
99 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
100 .prefixlen = 96,
101 .label = 4,
102 }, { /* ::/96 */
103 .prefix = &in6addr_any,
104 .prefixlen = 96,
105 .label = 3,
106 }, { /* ::1/128 */
107 .prefix = &in6addr_loopback,
108 .prefixlen = 128,
109 .label = 0,
110 }
111};
112
113/* Find label */
114static bool __ip6addrlbl_match(const struct ip6addrlbl_entry *p,
115 const struct in6_addr *addr,
116 int addrtype, int ifindex)
117{
118 if (p->ifindex && p->ifindex != ifindex)
119 return false;
120 if (p->addrtype && p->addrtype != addrtype)
121 return false;
122 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
123 return false;
124 return true;
125}
126
127static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
128 const struct in6_addr *addr,
129 int type, int ifindex)
130{
131 struct ip6addrlbl_entry *p;
132
133 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
134 if (__ip6addrlbl_match(p, addr, type, ifindex))
135 return p;
136 }
137 return NULL;
138}
139
140u32 ipv6_addr_label(struct net *net,
141 const struct in6_addr *addr, int type, int ifindex)
142{
143 u32 label;
144 struct ip6addrlbl_entry *p;
145
146 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
147
148 rcu_read_lock();
149 p = __ipv6_addr_label(net, addr, type, ifindex);
150 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
151 rcu_read_unlock();
152
153 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
154 __func__, addr, type, ifindex, label);
155
156 return label;
157}
158
159/* allocate one entry */
160static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
161 int prefixlen, int ifindex,
162 u32 label)
163{
164 struct ip6addrlbl_entry *newp;
165 int addrtype;
166
167 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
168 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
169
170 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
171
172 switch (addrtype) {
173 case IPV6_ADDR_MAPPED:
174 if (prefixlen > 96)
175 return ERR_PTR(-EINVAL);
176 if (prefixlen < 96)
177 addrtype = 0;
178 break;
179 case IPV6_ADDR_COMPATv4:
180 if (prefixlen != 96)
181 addrtype = 0;
182 break;
183 case IPV6_ADDR_LOOPBACK:
184 if (prefixlen != 128)
185 addrtype = 0;
186 break;
187 }
188
189 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
190 if (!newp)
191 return ERR_PTR(-ENOMEM);
192
193 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
194 newp->prefixlen = prefixlen;
195 newp->ifindex = ifindex;
196 newp->addrtype = addrtype;
197 newp->label = label;
198 INIT_HLIST_NODE(&newp->list);
199 return newp;
200}
201
202/* add a label */
203static int __ip6addrlbl_add(struct net *net, struct ip6addrlbl_entry *newp,
204 int replace)
205{
206 struct ip6addrlbl_entry *last = NULL, *p = NULL;
207 struct hlist_node *n;
208 int ret = 0;
209
210 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
211 replace);
212
213 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
214 if (p->prefixlen == newp->prefixlen &&
215 p->ifindex == newp->ifindex &&
216 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
217 if (!replace) {
218 ret = -EEXIST;
219 goto out;
220 }
221 hlist_replace_rcu(&p->list, &newp->list);
222 kfree_rcu(p, rcu);
223 goto out;
224 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
225 (p->prefixlen < newp->prefixlen)) {
226 hlist_add_before_rcu(&newp->list, &p->list);
227 goto out;
228 }
229 last = p;
230 }
231 if (last)
232 hlist_add_behind_rcu(&newp->list, &last->list);
233 else
234 hlist_add_head_rcu(&newp->list, &net->ipv6.ip6addrlbl_table.head);
235out:
236 if (!ret)
237 net->ipv6.ip6addrlbl_table.seq++;
238 return ret;
239}
240
241/* add a label */
242static int ip6addrlbl_add(struct net *net,
243 const struct in6_addr *prefix, int prefixlen,
244 int ifindex, u32 label, int replace)
245{
246 struct ip6addrlbl_entry *newp;
247 int ret = 0;
248
249 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
250 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
251 replace);
252
253 newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
254 if (IS_ERR(newp))
255 return PTR_ERR(newp);
256 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
257 ret = __ip6addrlbl_add(net, newp, replace);
258 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
259 if (ret)
260 kfree(newp);
261 return ret;
262}
263
264/* remove a label */
265static int __ip6addrlbl_del(struct net *net,
266 const struct in6_addr *prefix, int prefixlen,
267 int ifindex)
268{
269 struct ip6addrlbl_entry *p = NULL;
270 struct hlist_node *n;
271 int ret = -ESRCH;
272
273 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
274 __func__, prefix, prefixlen, ifindex);
275
276 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
277 if (p->prefixlen == prefixlen &&
278 p->ifindex == ifindex &&
279 ipv6_addr_equal(&p->prefix, prefix)) {
280 hlist_del_rcu(&p->list);
281 kfree_rcu(p, rcu);
282 ret = 0;
283 break;
284 }
285 }
286 return ret;
287}
288
289static int ip6addrlbl_del(struct net *net,
290 const struct in6_addr *prefix, int prefixlen,
291 int ifindex)
292{
293 struct in6_addr prefix_buf;
294 int ret;
295
296 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
297 __func__, prefix, prefixlen, ifindex);
298
299 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
300 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
301 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
302 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
303 return ret;
304}
305
306/* add default label */
307static int __net_init ip6addrlbl_net_init(struct net *net)
308{
309 int err = 0;
310 int i;
311
312 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
313
314 spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
315 INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
316
317 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
318 int ret = ip6addrlbl_add(net,
319 ip6addrlbl_init_table[i].prefix,
320 ip6addrlbl_init_table[i].prefixlen,
321 0,
322 ip6addrlbl_init_table[i].label, 0);
323 /* XXX: should we free all rules when we catch an error? */
324 if (ret && (!err || err != -ENOMEM))
325 err = ret;
326 }
327 return err;
328}
329
330static void __net_exit ip6addrlbl_net_exit(struct net *net)
331{
332 struct ip6addrlbl_entry *p = NULL;
333 struct hlist_node *n;
334
335 /* Remove all labels belonging to the exiting net */
336 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
337 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
338 hlist_del_rcu(&p->list);
339 kfree_rcu(p, rcu);
340 }
341 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
342}
343
344static struct pernet_operations ipv6_addr_label_ops = {
345 .init = ip6addrlbl_net_init,
346 .exit = ip6addrlbl_net_exit,
347};
348
349int __init ipv6_addr_label_init(void)
350{
351 return register_pernet_subsys(&ipv6_addr_label_ops);
352}
353
354void ipv6_addr_label_cleanup(void)
355{
356 unregister_pernet_subsys(&ipv6_addr_label_ops);
357}
358
359static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
360 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
361 [IFAL_LABEL] = { .len = sizeof(u32), },
362};
363
364static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
365{
366
367 struct net_device *dev;
368
369 rcu_read_lock();
370 dev = dev_get_by_index_rcu(net, ifindex);
371 rcu_read_unlock();
372
373 return dev != NULL;
374}
375
376static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
377 struct netlink_ext_ack *extack)
378{
379 struct net *net = sock_net(skb->sk);
380 struct ifaddrlblmsg *ifal;
381 struct nlattr *tb[IFAL_MAX+1];
382 struct in6_addr *pfx;
383 u32 label;
384 int err = 0;
385
386 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy,
387 extack);
388 if (err < 0)
389 return err;
390
391 ifal = nlmsg_data(nlh);
392
393 if (ifal->ifal_family != AF_INET6 ||
394 ifal->ifal_prefixlen > 128)
395 return -EINVAL;
396
397 if (!tb[IFAL_ADDRESS])
398 return -EINVAL;
399 pfx = nla_data(tb[IFAL_ADDRESS]);
400
401 if (!tb[IFAL_LABEL])
402 return -EINVAL;
403 label = nla_get_u32(tb[IFAL_LABEL]);
404 if (label == IPV6_ADDR_LABEL_DEFAULT)
405 return -EINVAL;
406
407 switch (nlh->nlmsg_type) {
408 case RTM_NEWADDRLABEL:
409 if (ifal->ifal_index &&
410 !addrlbl_ifindex_exists(net, ifal->ifal_index))
411 return -EINVAL;
412
413 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
414 ifal->ifal_index, label,
415 nlh->nlmsg_flags & NLM_F_REPLACE);
416 break;
417 case RTM_DELADDRLABEL:
418 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
419 ifal->ifal_index);
420 break;
421 default:
422 err = -EOPNOTSUPP;
423 }
424 return err;
425}
426
427static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
428 int prefixlen, int ifindex, u32 lseq)
429{
430 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
431 ifal->ifal_family = AF_INET6;
432 ifal->ifal_prefixlen = prefixlen;
433 ifal->ifal_flags = 0;
434 ifal->ifal_index = ifindex;
435 ifal->ifal_seq = lseq;
436};
437
438static int ip6addrlbl_fill(struct sk_buff *skb,
439 struct ip6addrlbl_entry *p,
440 u32 lseq,
441 u32 portid, u32 seq, int event,
442 unsigned int flags)
443{
444 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
445 sizeof(struct ifaddrlblmsg), flags);
446 if (!nlh)
447 return -EMSGSIZE;
448
449 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
450
451 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
452 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
453 nlmsg_cancel(skb, nlh);
454 return -EMSGSIZE;
455 }
456
457 nlmsg_end(skb, nlh);
458 return 0;
459}
460
461static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
462{
463 struct net *net = sock_net(skb->sk);
464 struct ip6addrlbl_entry *p;
465 int idx = 0, s_idx = cb->args[0];
466 int err;
467
468 rcu_read_lock();
469 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
470 if (idx >= s_idx) {
471 err = ip6addrlbl_fill(skb, p,
472 net->ipv6.ip6addrlbl_table.seq,
473 NETLINK_CB(cb->skb).portid,
474 cb->nlh->nlmsg_seq,
475 RTM_NEWADDRLABEL,
476 NLM_F_MULTI);
477 if (err < 0)
478 break;
479 }
480 idx++;
481 }
482 rcu_read_unlock();
483 cb->args[0] = idx;
484 return skb->len;
485}
486
487static inline int ip6addrlbl_msgsize(void)
488{
489 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
490 + nla_total_size(16) /* IFAL_ADDRESS */
491 + nla_total_size(4); /* IFAL_LABEL */
492}
493
494static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
495 struct netlink_ext_ack *extack)
496{
497 struct net *net = sock_net(in_skb->sk);
498 struct ifaddrlblmsg *ifal;
499 struct nlattr *tb[IFAL_MAX+1];
500 struct in6_addr *addr;
501 u32 lseq;
502 int err = 0;
503 struct ip6addrlbl_entry *p;
504 struct sk_buff *skb;
505
506 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy,
507 extack);
508 if (err < 0)
509 return err;
510
511 ifal = nlmsg_data(nlh);
512
513 if (ifal->ifal_family != AF_INET6 ||
514 ifal->ifal_prefixlen != 128)
515 return -EINVAL;
516
517 if (ifal->ifal_index &&
518 !addrlbl_ifindex_exists(net, ifal->ifal_index))
519 return -EINVAL;
520
521 if (!tb[IFAL_ADDRESS])
522 return -EINVAL;
523 addr = nla_data(tb[IFAL_ADDRESS]);
524
525 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
526 if (!skb)
527 return -ENOBUFS;
528
529 err = -ESRCH;
530
531 rcu_read_lock();
532 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
533 lseq = net->ipv6.ip6addrlbl_table.seq;
534 if (p)
535 err = ip6addrlbl_fill(skb, p, lseq,
536 NETLINK_CB(in_skb).portid,
537 nlh->nlmsg_seq,
538 RTM_NEWADDRLABEL, 0);
539 rcu_read_unlock();
540
541 if (err < 0) {
542 WARN_ON(err == -EMSGSIZE);
543 kfree_skb(skb);
544 } else {
545 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
546 }
547 return err;
548}
549
550int __init ipv6_addr_label_rtnl_register(void)
551{
552 int ret;
553
554 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDRLABEL,
555 ip6addrlbl_newdel,
556 NULL, RTNL_FLAG_DOIT_UNLOCKED);
557 if (ret < 0)
558 return ret;
559 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDRLABEL,
560 ip6addrlbl_newdel,
561 NULL, RTNL_FLAG_DOIT_UNLOCKED);
562 if (ret < 0)
563 return ret;
564 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDRLABEL,
565 ip6addrlbl_get,
566 ip6addrlbl_dump, RTNL_FLAG_DOIT_UNLOCKED);
567 return ret;
568}