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1/*
2 * IPv6 Address Label subsystem
3 * for the IPv6 "Default" Source Address Selection
4 *
5 * Copyright (C)2007 USAGI/WIDE Project
6 */
7/*
8 * Author:
9 * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
10 */
11
12#include <linux/kernel.h>
13#include <linux/list.h>
14#include <linux/rcupdate.h>
15#include <linux/in6.h>
16#include <linux/slab.h>
17#include <net/addrconf.h>
18#include <linux/if_addrlabel.h>
19#include <linux/netlink.h>
20#include <linux/rtnetlink.h>
21
22#if 0
23#define ADDRLABEL(x...) printk(x)
24#else
25#define ADDRLABEL(x...) do { ; } while (0)
26#endif
27
28/*
29 * Policy Table
30 */
31struct ip6addrlbl_entry {
32 possible_net_t lbl_net;
33 struct in6_addr prefix;
34 int prefixlen;
35 int ifindex;
36 int addrtype;
37 u32 label;
38 struct hlist_node list;
39 atomic_t refcnt;
40 struct rcu_head rcu;
41};
42
43static struct ip6addrlbl_table
44{
45 struct hlist_head head;
46 spinlock_t lock;
47 u32 seq;
48} ip6addrlbl_table;
49
50static inline
51struct net *ip6addrlbl_net(const struct ip6addrlbl_entry *lbl)
52{
53 return read_pnet(&lbl->lbl_net);
54}
55
56/*
57 * Default policy table (RFC6724 + extensions)
58 *
59 * prefix addr_type label
60 * -------------------------------------------------------------------------
61 * ::1/128 LOOPBACK 0
62 * ::/0 N/A 1
63 * 2002::/16 N/A 2
64 * ::/96 COMPATv4 3
65 * ::ffff:0:0/96 V4MAPPED 4
66 * fc00::/7 N/A 5 ULA (RFC 4193)
67 * 2001::/32 N/A 6 Teredo (RFC 4380)
68 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
69 * fec0::/10 N/A 11 Site-local
70 * (deprecated by RFC3879)
71 * 3ffe::/16 N/A 12 6bone
72 *
73 * Note: 0xffffffff is used if we do not have any policies.
74 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
75 */
76
77#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
78
79static const __net_initconst struct ip6addrlbl_init_table
80{
81 const struct in6_addr *prefix;
82 int prefixlen;
83 u32 label;
84} ip6addrlbl_init_table[] = {
85 { /* ::/0 */
86 .prefix = &in6addr_any,
87 .label = 1,
88 }, { /* fc00::/7 */
89 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
90 .prefixlen = 7,
91 .label = 5,
92 }, { /* fec0::/10 */
93 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
94 .prefixlen = 10,
95 .label = 11,
96 }, { /* 2002::/16 */
97 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
98 .prefixlen = 16,
99 .label = 2,
100 }, { /* 3ffe::/16 */
101 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
102 .prefixlen = 16,
103 .label = 12,
104 }, { /* 2001::/32 */
105 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
106 .prefixlen = 32,
107 .label = 6,
108 }, { /* 2001:10::/28 */
109 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
110 .prefixlen = 28,
111 .label = 7,
112 }, { /* ::ffff:0:0 */
113 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
114 .prefixlen = 96,
115 .label = 4,
116 }, { /* ::/96 */
117 .prefix = &in6addr_any,
118 .prefixlen = 96,
119 .label = 3,
120 }, { /* ::1/128 */
121 .prefix = &in6addr_loopback,
122 .prefixlen = 128,
123 .label = 0,
124 }
125};
126
127/* Object management */
128static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
129{
130 kfree(p);
131}
132
133static void ip6addrlbl_free_rcu(struct rcu_head *h)
134{
135 ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
136}
137
138static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p)
139{
140 return atomic_inc_not_zero(&p->refcnt);
141}
142
143static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
144{
145 if (atomic_dec_and_test(&p->refcnt))
146 call_rcu(&p->rcu, ip6addrlbl_free_rcu);
147}
148
149/* Find label */
150static bool __ip6addrlbl_match(struct net *net,
151 const struct ip6addrlbl_entry *p,
152 const struct in6_addr *addr,
153 int addrtype, int ifindex)
154{
155 if (!net_eq(ip6addrlbl_net(p), net))
156 return false;
157 if (p->ifindex && p->ifindex != ifindex)
158 return false;
159 if (p->addrtype && p->addrtype != addrtype)
160 return false;
161 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
162 return false;
163 return true;
164}
165
166static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
167 const struct in6_addr *addr,
168 int type, int ifindex)
169{
170 struct ip6addrlbl_entry *p;
171 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
172 if (__ip6addrlbl_match(net, p, addr, type, ifindex))
173 return p;
174 }
175 return NULL;
176}
177
178u32 ipv6_addr_label(struct net *net,
179 const struct in6_addr *addr, int type, int ifindex)
180{
181 u32 label;
182 struct ip6addrlbl_entry *p;
183
184 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
185
186 rcu_read_lock();
187 p = __ipv6_addr_label(net, addr, type, ifindex);
188 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
189 rcu_read_unlock();
190
191 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
192 __func__, addr, type, ifindex, label);
193
194 return label;
195}
196
197/* allocate one entry */
198static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net,
199 const struct in6_addr *prefix,
200 int prefixlen, int ifindex,
201 u32 label)
202{
203 struct ip6addrlbl_entry *newp;
204 int addrtype;
205
206 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
207 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
208
209 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
210
211 switch (addrtype) {
212 case IPV6_ADDR_MAPPED:
213 if (prefixlen > 96)
214 return ERR_PTR(-EINVAL);
215 if (prefixlen < 96)
216 addrtype = 0;
217 break;
218 case IPV6_ADDR_COMPATv4:
219 if (prefixlen != 96)
220 addrtype = 0;
221 break;
222 case IPV6_ADDR_LOOPBACK:
223 if (prefixlen != 128)
224 addrtype = 0;
225 break;
226 }
227
228 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
229 if (!newp)
230 return ERR_PTR(-ENOMEM);
231
232 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
233 newp->prefixlen = prefixlen;
234 newp->ifindex = ifindex;
235 newp->addrtype = addrtype;
236 newp->label = label;
237 INIT_HLIST_NODE(&newp->list);
238 write_pnet(&newp->lbl_net, net);
239 atomic_set(&newp->refcnt, 1);
240 return newp;
241}
242
243/* add a label */
244static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
245{
246 struct hlist_node *n;
247 struct ip6addrlbl_entry *last = NULL, *p = NULL;
248 int ret = 0;
249
250 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
251 replace);
252
253 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
254 if (p->prefixlen == newp->prefixlen &&
255 net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
256 p->ifindex == newp->ifindex &&
257 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
258 if (!replace) {
259 ret = -EEXIST;
260 goto out;
261 }
262 hlist_replace_rcu(&p->list, &newp->list);
263 ip6addrlbl_put(p);
264 goto out;
265 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
266 (p->prefixlen < newp->prefixlen)) {
267 hlist_add_before_rcu(&newp->list, &p->list);
268 goto out;
269 }
270 last = p;
271 }
272 if (last)
273 hlist_add_behind_rcu(&newp->list, &last->list);
274 else
275 hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
276out:
277 if (!ret)
278 ip6addrlbl_table.seq++;
279 return ret;
280}
281
282/* add a label */
283static int ip6addrlbl_add(struct net *net,
284 const struct in6_addr *prefix, int prefixlen,
285 int ifindex, u32 label, int replace)
286{
287 struct ip6addrlbl_entry *newp;
288 int ret = 0;
289
290 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
291 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
292 replace);
293
294 newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
295 if (IS_ERR(newp))
296 return PTR_ERR(newp);
297 spin_lock(&ip6addrlbl_table.lock);
298 ret = __ip6addrlbl_add(newp, replace);
299 spin_unlock(&ip6addrlbl_table.lock);
300 if (ret)
301 ip6addrlbl_free(newp);
302 return ret;
303}
304
305/* remove a label */
306static int __ip6addrlbl_del(struct net *net,
307 const struct in6_addr *prefix, int prefixlen,
308 int ifindex)
309{
310 struct ip6addrlbl_entry *p = NULL;
311 struct hlist_node *n;
312 int ret = -ESRCH;
313
314 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
315 __func__, prefix, prefixlen, ifindex);
316
317 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
318 if (p->prefixlen == prefixlen &&
319 net_eq(ip6addrlbl_net(p), net) &&
320 p->ifindex == ifindex &&
321 ipv6_addr_equal(&p->prefix, prefix)) {
322 hlist_del_rcu(&p->list);
323 ip6addrlbl_put(p);
324 ret = 0;
325 break;
326 }
327 }
328 return ret;
329}
330
331static int ip6addrlbl_del(struct net *net,
332 const struct in6_addr *prefix, int prefixlen,
333 int ifindex)
334{
335 struct in6_addr prefix_buf;
336 int ret;
337
338 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
339 __func__, prefix, prefixlen, ifindex);
340
341 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
342 spin_lock(&ip6addrlbl_table.lock);
343 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
344 spin_unlock(&ip6addrlbl_table.lock);
345 return ret;
346}
347
348/* add default label */
349static int __net_init ip6addrlbl_net_init(struct net *net)
350{
351 int err = 0;
352 int i;
353
354 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
355
356 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
357 int ret = ip6addrlbl_add(net,
358 ip6addrlbl_init_table[i].prefix,
359 ip6addrlbl_init_table[i].prefixlen,
360 0,
361 ip6addrlbl_init_table[i].label, 0);
362 /* XXX: should we free all rules when we catch an error? */
363 if (ret && (!err || err != -ENOMEM))
364 err = ret;
365 }
366 return err;
367}
368
369static void __net_exit ip6addrlbl_net_exit(struct net *net)
370{
371 struct ip6addrlbl_entry *p = NULL;
372 struct hlist_node *n;
373
374 /* Remove all labels belonging to the exiting net */
375 spin_lock(&ip6addrlbl_table.lock);
376 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
377 if (net_eq(ip6addrlbl_net(p), net)) {
378 hlist_del_rcu(&p->list);
379 ip6addrlbl_put(p);
380 }
381 }
382 spin_unlock(&ip6addrlbl_table.lock);
383}
384
385static struct pernet_operations ipv6_addr_label_ops = {
386 .init = ip6addrlbl_net_init,
387 .exit = ip6addrlbl_net_exit,
388};
389
390int __init ipv6_addr_label_init(void)
391{
392 spin_lock_init(&ip6addrlbl_table.lock);
393
394 return register_pernet_subsys(&ipv6_addr_label_ops);
395}
396
397void ipv6_addr_label_cleanup(void)
398{
399 unregister_pernet_subsys(&ipv6_addr_label_ops);
400}
401
402static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
403 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
404 [IFAL_LABEL] = { .len = sizeof(u32), },
405};
406
407static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh)
408{
409 struct net *net = sock_net(skb->sk);
410 struct ifaddrlblmsg *ifal;
411 struct nlattr *tb[IFAL_MAX+1];
412 struct in6_addr *pfx;
413 u32 label;
414 int err = 0;
415
416 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
417 if (err < 0)
418 return err;
419
420 ifal = nlmsg_data(nlh);
421
422 if (ifal->ifal_family != AF_INET6 ||
423 ifal->ifal_prefixlen > 128)
424 return -EINVAL;
425
426 if (!tb[IFAL_ADDRESS])
427 return -EINVAL;
428 pfx = nla_data(tb[IFAL_ADDRESS]);
429
430 if (!tb[IFAL_LABEL])
431 return -EINVAL;
432 label = nla_get_u32(tb[IFAL_LABEL]);
433 if (label == IPV6_ADDR_LABEL_DEFAULT)
434 return -EINVAL;
435
436 switch (nlh->nlmsg_type) {
437 case RTM_NEWADDRLABEL:
438 if (ifal->ifal_index &&
439 !__dev_get_by_index(net, ifal->ifal_index))
440 return -EINVAL;
441
442 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
443 ifal->ifal_index, label,
444 nlh->nlmsg_flags & NLM_F_REPLACE);
445 break;
446 case RTM_DELADDRLABEL:
447 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
448 ifal->ifal_index);
449 break;
450 default:
451 err = -EOPNOTSUPP;
452 }
453 return err;
454}
455
456static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
457 int prefixlen, int ifindex, u32 lseq)
458{
459 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
460 ifal->ifal_family = AF_INET6;
461 ifal->ifal_prefixlen = prefixlen;
462 ifal->ifal_flags = 0;
463 ifal->ifal_index = ifindex;
464 ifal->ifal_seq = lseq;
465};
466
467static int ip6addrlbl_fill(struct sk_buff *skb,
468 struct ip6addrlbl_entry *p,
469 u32 lseq,
470 u32 portid, u32 seq, int event,
471 unsigned int flags)
472{
473 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
474 sizeof(struct ifaddrlblmsg), flags);
475 if (!nlh)
476 return -EMSGSIZE;
477
478 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
479
480 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
481 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
482 nlmsg_cancel(skb, nlh);
483 return -EMSGSIZE;
484 }
485
486 nlmsg_end(skb, nlh);
487 return 0;
488}
489
490static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
491{
492 struct net *net = sock_net(skb->sk);
493 struct ip6addrlbl_entry *p;
494 int idx = 0, s_idx = cb->args[0];
495 int err;
496
497 rcu_read_lock();
498 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
499 if (idx >= s_idx &&
500 net_eq(ip6addrlbl_net(p), net)) {
501 err = ip6addrlbl_fill(skb, p,
502 ip6addrlbl_table.seq,
503 NETLINK_CB(cb->skb).portid,
504 cb->nlh->nlmsg_seq,
505 RTM_NEWADDRLABEL,
506 NLM_F_MULTI);
507 if (err < 0)
508 break;
509 }
510 idx++;
511 }
512 rcu_read_unlock();
513 cb->args[0] = idx;
514 return skb->len;
515}
516
517static inline int ip6addrlbl_msgsize(void)
518{
519 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
520 + nla_total_size(16) /* IFAL_ADDRESS */
521 + nla_total_size(4); /* IFAL_LABEL */
522}
523
524static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh)
525{
526 struct net *net = sock_net(in_skb->sk);
527 struct ifaddrlblmsg *ifal;
528 struct nlattr *tb[IFAL_MAX+1];
529 struct in6_addr *addr;
530 u32 lseq;
531 int err = 0;
532 struct ip6addrlbl_entry *p;
533 struct sk_buff *skb;
534
535 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
536 if (err < 0)
537 return err;
538
539 ifal = nlmsg_data(nlh);
540
541 if (ifal->ifal_family != AF_INET6 ||
542 ifal->ifal_prefixlen != 128)
543 return -EINVAL;
544
545 if (ifal->ifal_index &&
546 !__dev_get_by_index(net, ifal->ifal_index))
547 return -EINVAL;
548
549 if (!tb[IFAL_ADDRESS])
550 return -EINVAL;
551 addr = nla_data(tb[IFAL_ADDRESS]);
552
553 rcu_read_lock();
554 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
555 if (p && !ip6addrlbl_hold(p))
556 p = NULL;
557 lseq = ip6addrlbl_table.seq;
558 rcu_read_unlock();
559
560 if (!p) {
561 err = -ESRCH;
562 goto out;
563 }
564
565 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
566 if (!skb) {
567 ip6addrlbl_put(p);
568 return -ENOBUFS;
569 }
570
571 err = ip6addrlbl_fill(skb, p, lseq,
572 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
573 RTM_NEWADDRLABEL, 0);
574
575 ip6addrlbl_put(p);
576
577 if (err < 0) {
578 WARN_ON(err == -EMSGSIZE);
579 kfree_skb(skb);
580 goto out;
581 }
582
583 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
584out:
585 return err;
586}
587
588void __init ipv6_addr_label_rtnl_register(void)
589{
590 __rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel,
591 NULL, NULL);
592 __rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel,
593 NULL, NULL);
594 __rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get,
595 ip6addrlbl_dump, NULL);
596}
597
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 WRITE_ONCE(net->ipv6.ip6addrlbl_table.seq,
238 net->ipv6.ip6addrlbl_table.seq + 1);
239 return ret;
240}
241
242/* add a label */
243static int ip6addrlbl_add(struct net *net,
244 const struct in6_addr *prefix, int prefixlen,
245 int ifindex, u32 label, int replace)
246{
247 struct ip6addrlbl_entry *newp;
248 int ret = 0;
249
250 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
251 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
252 replace);
253
254 newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
255 if (IS_ERR(newp))
256 return PTR_ERR(newp);
257 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
258 ret = __ip6addrlbl_add(net, newp, replace);
259 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
260 if (ret)
261 kfree(newp);
262 return ret;
263}
264
265/* remove a label */
266static int __ip6addrlbl_del(struct net *net,
267 const struct in6_addr *prefix, int prefixlen,
268 int ifindex)
269{
270 struct ip6addrlbl_entry *p = NULL;
271 struct hlist_node *n;
272 int ret = -ESRCH;
273
274 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
275 __func__, prefix, prefixlen, ifindex);
276
277 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
278 if (p->prefixlen == prefixlen &&
279 p->ifindex == ifindex &&
280 ipv6_addr_equal(&p->prefix, prefix)) {
281 hlist_del_rcu(&p->list);
282 kfree_rcu(p, rcu);
283 ret = 0;
284 break;
285 }
286 }
287 return ret;
288}
289
290static int ip6addrlbl_del(struct net *net,
291 const struct in6_addr *prefix, int prefixlen,
292 int ifindex)
293{
294 struct in6_addr prefix_buf;
295 int ret;
296
297 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
298 __func__, prefix, prefixlen, ifindex);
299
300 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
301 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
302 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
303 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
304 return ret;
305}
306
307/* add default label */
308static int __net_init ip6addrlbl_net_init(struct net *net)
309{
310 struct ip6addrlbl_entry *p = NULL;
311 struct hlist_node *n;
312 int err;
313 int i;
314
315 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
316
317 spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
318 INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
319
320 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
321 err = ip6addrlbl_add(net,
322 ip6addrlbl_init_table[i].prefix,
323 ip6addrlbl_init_table[i].prefixlen,
324 0,
325 ip6addrlbl_init_table[i].label, 0);
326 if (err)
327 goto err_ip6addrlbl_add;
328 }
329 return 0;
330
331err_ip6addrlbl_add:
332 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
333 hlist_del_rcu(&p->list);
334 kfree_rcu(p, rcu);
335 }
336 return err;
337}
338
339static void __net_exit ip6addrlbl_net_exit(struct net *net)
340{
341 struct ip6addrlbl_entry *p = NULL;
342 struct hlist_node *n;
343
344 /* Remove all labels belonging to the exiting net */
345 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
346 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
347 hlist_del_rcu(&p->list);
348 kfree_rcu(p, rcu);
349 }
350 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
351}
352
353static struct pernet_operations ipv6_addr_label_ops = {
354 .init = ip6addrlbl_net_init,
355 .exit = ip6addrlbl_net_exit,
356};
357
358int __init ipv6_addr_label_init(void)
359{
360 return register_pernet_subsys(&ipv6_addr_label_ops);
361}
362
363void ipv6_addr_label_cleanup(void)
364{
365 unregister_pernet_subsys(&ipv6_addr_label_ops);
366}
367
368static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
369 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
370 [IFAL_LABEL] = { .len = sizeof(u32), },
371};
372
373static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
374{
375
376 struct net_device *dev;
377
378 rcu_read_lock();
379 dev = dev_get_by_index_rcu(net, ifindex);
380 rcu_read_unlock();
381
382 return dev != NULL;
383}
384
385static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
386 struct netlink_ext_ack *extack)
387{
388 struct net *net = sock_net(skb->sk);
389 struct ifaddrlblmsg *ifal;
390 struct nlattr *tb[IFAL_MAX+1];
391 struct in6_addr *pfx;
392 u32 label;
393 int err = 0;
394
395 err = nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb, IFAL_MAX,
396 ifal_policy, extack);
397 if (err < 0)
398 return err;
399
400 ifal = nlmsg_data(nlh);
401
402 if (ifal->ifal_family != AF_INET6 ||
403 ifal->ifal_prefixlen > 128)
404 return -EINVAL;
405
406 if (!tb[IFAL_ADDRESS])
407 return -EINVAL;
408 pfx = nla_data(tb[IFAL_ADDRESS]);
409
410 if (!tb[IFAL_LABEL])
411 return -EINVAL;
412 label = nla_get_u32(tb[IFAL_LABEL]);
413 if (label == IPV6_ADDR_LABEL_DEFAULT)
414 return -EINVAL;
415
416 switch (nlh->nlmsg_type) {
417 case RTM_NEWADDRLABEL:
418 if (ifal->ifal_index &&
419 !addrlbl_ifindex_exists(net, ifal->ifal_index))
420 return -EINVAL;
421
422 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
423 ifal->ifal_index, label,
424 nlh->nlmsg_flags & NLM_F_REPLACE);
425 break;
426 case RTM_DELADDRLABEL:
427 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
428 ifal->ifal_index);
429 break;
430 default:
431 err = -EOPNOTSUPP;
432 }
433 return err;
434}
435
436static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
437 int prefixlen, int ifindex, u32 lseq)
438{
439 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
440 ifal->ifal_family = AF_INET6;
441 ifal->__ifal_reserved = 0;
442 ifal->ifal_prefixlen = prefixlen;
443 ifal->ifal_flags = 0;
444 ifal->ifal_index = ifindex;
445 ifal->ifal_seq = lseq;
446};
447
448static int ip6addrlbl_fill(struct sk_buff *skb,
449 const struct ip6addrlbl_entry *p,
450 u32 lseq,
451 u32 portid, u32 seq, int event,
452 unsigned int flags)
453{
454 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
455 sizeof(struct ifaddrlblmsg), flags);
456 if (!nlh)
457 return -EMSGSIZE;
458
459 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
460
461 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
462 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
463 nlmsg_cancel(skb, nlh);
464 return -EMSGSIZE;
465 }
466
467 nlmsg_end(skb, nlh);
468 return 0;
469}
470
471static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
472 struct netlink_ext_ack *extack)
473{
474 struct ifaddrlblmsg *ifal;
475
476 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
477 NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
478 return -EINVAL;
479 }
480
481 ifal = nlmsg_data(nlh);
482 if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
483 ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
484 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
485 return -EINVAL;
486 }
487
488 if (nlmsg_attrlen(nlh, sizeof(*ifal))) {
489 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header for address label dump request");
490 return -EINVAL;
491 }
492
493 return 0;
494}
495
496static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
497{
498 const struct nlmsghdr *nlh = cb->nlh;
499 struct net *net = sock_net(skb->sk);
500 struct ip6addrlbl_entry *p;
501 int idx = 0, s_idx = cb->args[0];
502 int err = 0;
503 u32 lseq;
504
505 if (cb->strict_check) {
506 err = ip6addrlbl_valid_dump_req(nlh, cb->extack);
507 if (err < 0)
508 return err;
509 }
510
511 rcu_read_lock();
512 lseq = READ_ONCE(net->ipv6.ip6addrlbl_table.seq);
513 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
514 if (idx >= s_idx) {
515 err = ip6addrlbl_fill(skb, p,
516 lseq,
517 NETLINK_CB(cb->skb).portid,
518 nlh->nlmsg_seq,
519 RTM_NEWADDRLABEL,
520 NLM_F_MULTI);
521 if (err < 0)
522 break;
523 }
524 idx++;
525 }
526 rcu_read_unlock();
527 cb->args[0] = idx;
528 return err;
529}
530
531static inline int ip6addrlbl_msgsize(void)
532{
533 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
534 + nla_total_size(16) /* IFAL_ADDRESS */
535 + nla_total_size(4); /* IFAL_LABEL */
536}
537
538static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
539 const struct nlmsghdr *nlh,
540 struct nlattr **tb,
541 struct netlink_ext_ack *extack)
542{
543 struct ifaddrlblmsg *ifal;
544 int i, err;
545
546 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
547 NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
548 return -EINVAL;
549 }
550
551 if (!netlink_strict_get_check(skb))
552 return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
553 IFAL_MAX, ifal_policy, extack);
554
555 ifal = nlmsg_data(nlh);
556 if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
557 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
558 return -EINVAL;
559 }
560
561 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifal), tb, IFAL_MAX,
562 ifal_policy, extack);
563 if (err)
564 return err;
565
566 for (i = 0; i <= IFAL_MAX; i++) {
567 if (!tb[i])
568 continue;
569
570 switch (i) {
571 case IFAL_ADDRESS:
572 break;
573 default:
574 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in addrlabel get request");
575 return -EINVAL;
576 }
577 }
578
579 return 0;
580}
581
582static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
583 struct netlink_ext_ack *extack)
584{
585 struct net *net = sock_net(in_skb->sk);
586 struct ifaddrlblmsg *ifal;
587 struct nlattr *tb[IFAL_MAX+1];
588 struct in6_addr *addr;
589 u32 lseq;
590 int err = 0;
591 struct ip6addrlbl_entry *p;
592 struct sk_buff *skb;
593
594 err = ip6addrlbl_valid_get_req(in_skb, nlh, tb, extack);
595 if (err < 0)
596 return err;
597
598 ifal = nlmsg_data(nlh);
599
600 if (ifal->ifal_family != AF_INET6 ||
601 ifal->ifal_prefixlen != 128)
602 return -EINVAL;
603
604 if (ifal->ifal_index &&
605 !addrlbl_ifindex_exists(net, ifal->ifal_index))
606 return -EINVAL;
607
608 if (!tb[IFAL_ADDRESS])
609 return -EINVAL;
610 addr = nla_data(tb[IFAL_ADDRESS]);
611
612 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
613 if (!skb)
614 return -ENOBUFS;
615
616 err = -ESRCH;
617
618 rcu_read_lock();
619 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
620 lseq = READ_ONCE(net->ipv6.ip6addrlbl_table.seq);
621 if (p)
622 err = ip6addrlbl_fill(skb, p, lseq,
623 NETLINK_CB(in_skb).portid,
624 nlh->nlmsg_seq,
625 RTM_NEWADDRLABEL, 0);
626 rcu_read_unlock();
627
628 if (err < 0) {
629 WARN_ON(err == -EMSGSIZE);
630 kfree_skb(skb);
631 } else {
632 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
633 }
634 return err;
635}
636
637static const struct rtnl_msg_handler ipv6_adddr_label_rtnl_msg_handlers[] __initconst_or_module = {
638 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDRLABEL,
639 .doit = ip6addrlbl_newdel, .flags = RTNL_FLAG_DOIT_UNLOCKED},
640 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDRLABEL,
641 .doit = ip6addrlbl_newdel, .flags = RTNL_FLAG_DOIT_UNLOCKED},
642 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDRLABEL,
643 .doit = ip6addrlbl_get, .dumpit = ip6addrlbl_dump,
644 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
645};
646
647int __init ipv6_addr_label_rtnl_register(void)
648{
649 return rtnl_register_many(ipv6_adddr_label_rtnl_msg_handlers);
650}