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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{
33#ifdef CONFIG_NET_NS
34 struct net *lbl_net;
35#endif
36 struct in6_addr prefix;
37 int prefixlen;
38 int ifindex;
39 int addrtype;
40 u32 label;
41 struct hlist_node list;
42 atomic_t refcnt;
43 struct rcu_head rcu;
44};
45
46static struct ip6addrlbl_table
47{
48 struct hlist_head head;
49 spinlock_t lock;
50 u32 seq;
51} ip6addrlbl_table;
52
53static inline
54struct net *ip6addrlbl_net(const struct ip6addrlbl_entry *lbl)
55{
56 return read_pnet(&lbl->lbl_net);
57}
58
59/*
60 * Default policy table (RFC3484 + extensions)
61 *
62 * prefix addr_type label
63 * -------------------------------------------------------------------------
64 * ::1/128 LOOPBACK 0
65 * ::/0 N/A 1
66 * 2002::/16 N/A 2
67 * ::/96 COMPATv4 3
68 * ::ffff:0:0/96 V4MAPPED 4
69 * fc00::/7 N/A 5 ULA (RFC 4193)
70 * 2001::/32 N/A 6 Teredo (RFC 4380)
71 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
72 *
73 * Note: 0xffffffff is used if we do not have any policies.
74 */
75
76#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
77
78static const __net_initdata struct ip6addrlbl_init_table
79{
80 const struct in6_addr *prefix;
81 int prefixlen;
82 u32 label;
83} ip6addrlbl_init_table[] = {
84 { /* ::/0 */
85 .prefix = &in6addr_any,
86 .label = 1,
87 },{ /* fc00::/7 */
88 .prefix = &(struct in6_addr){{{ 0xfc }}},
89 .prefixlen = 7,
90 .label = 5,
91 },{ /* 2002::/16 */
92 .prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
93 .prefixlen = 16,
94 .label = 2,
95 },{ /* 2001::/32 */
96 .prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
97 .prefixlen = 32,
98 .label = 6,
99 },{ /* 2001:10::/28 */
100 .prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
101 .prefixlen = 28,
102 .label = 7,
103 },{ /* ::ffff:0:0 */
104 .prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
105 .prefixlen = 96,
106 .label = 4,
107 },{ /* ::/96 */
108 .prefix = &in6addr_any,
109 .prefixlen = 96,
110 .label = 3,
111 },{ /* ::1/128 */
112 .prefix = &in6addr_loopback,
113 .prefixlen = 128,
114 .label = 0,
115 }
116};
117
118/* Object management */
119static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
120{
121#ifdef CONFIG_NET_NS
122 release_net(p->lbl_net);
123#endif
124 kfree(p);
125}
126
127static void ip6addrlbl_free_rcu(struct rcu_head *h)
128{
129 ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
130}
131
132static inline int ip6addrlbl_hold(struct ip6addrlbl_entry *p)
133{
134 return atomic_inc_not_zero(&p->refcnt);
135}
136
137static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
138{
139 if (atomic_dec_and_test(&p->refcnt))
140 call_rcu(&p->rcu, ip6addrlbl_free_rcu);
141}
142
143/* Find label */
144static int __ip6addrlbl_match(struct net *net,
145 struct ip6addrlbl_entry *p,
146 const struct in6_addr *addr,
147 int addrtype, int ifindex)
148{
149 if (!net_eq(ip6addrlbl_net(p), net))
150 return 0;
151 if (p->ifindex && p->ifindex != ifindex)
152 return 0;
153 if (p->addrtype && p->addrtype != addrtype)
154 return 0;
155 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
156 return 0;
157 return 1;
158}
159
160static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
161 const struct in6_addr *addr,
162 int type, int ifindex)
163{
164 struct hlist_node *pos;
165 struct ip6addrlbl_entry *p;
166 hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
167 if (__ip6addrlbl_match(net, p, addr, type, ifindex))
168 return p;
169 }
170 return NULL;
171}
172
173u32 ipv6_addr_label(struct net *net,
174 const struct in6_addr *addr, int type, int ifindex)
175{
176 u32 label;
177 struct ip6addrlbl_entry *p;
178
179 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
180
181 rcu_read_lock();
182 p = __ipv6_addr_label(net, addr, type, ifindex);
183 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
184 rcu_read_unlock();
185
186 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
187 __func__, addr, type, ifindex, label);
188
189 return label;
190}
191
192/* allocate one entry */
193static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net,
194 const struct in6_addr *prefix,
195 int prefixlen, int ifindex,
196 u32 label)
197{
198 struct ip6addrlbl_entry *newp;
199 int addrtype;
200
201 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
202 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
203
204 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
205
206 switch (addrtype) {
207 case IPV6_ADDR_MAPPED:
208 if (prefixlen > 96)
209 return ERR_PTR(-EINVAL);
210 if (prefixlen < 96)
211 addrtype = 0;
212 break;
213 case IPV6_ADDR_COMPATv4:
214 if (prefixlen != 96)
215 addrtype = 0;
216 break;
217 case IPV6_ADDR_LOOPBACK:
218 if (prefixlen != 128)
219 addrtype = 0;
220 break;
221 }
222
223 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
224 if (!newp)
225 return ERR_PTR(-ENOMEM);
226
227 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
228 newp->prefixlen = prefixlen;
229 newp->ifindex = ifindex;
230 newp->addrtype = addrtype;
231 newp->label = label;
232 INIT_HLIST_NODE(&newp->list);
233#ifdef CONFIG_NET_NS
234 newp->lbl_net = hold_net(net);
235#endif
236 atomic_set(&newp->refcnt, 1);
237 return newp;
238}
239
240/* add a label */
241static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
242{
243 int ret = 0;
244
245 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n",
246 __func__,
247 newp, replace);
248
249 if (hlist_empty(&ip6addrlbl_table.head)) {
250 hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
251 } else {
252 struct hlist_node *pos, *n;
253 struct ip6addrlbl_entry *p = NULL;
254 hlist_for_each_entry_safe(p, pos, n,
255 &ip6addrlbl_table.head, list) {
256 if (p->prefixlen == newp->prefixlen &&
257 net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
258 p->ifindex == newp->ifindex &&
259 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
260 if (!replace) {
261 ret = -EEXIST;
262 goto out;
263 }
264 hlist_replace_rcu(&p->list, &newp->list);
265 ip6addrlbl_put(p);
266 goto out;
267 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
268 (p->prefixlen < newp->prefixlen)) {
269 hlist_add_before_rcu(&newp->list, &p->list);
270 goto out;
271 }
272 }
273 hlist_add_after_rcu(&p->list, &newp->list);
274 }
275out:
276 if (!ret)
277 ip6addrlbl_table.seq++;
278 return ret;
279}
280
281/* add a label */
282static int ip6addrlbl_add(struct net *net,
283 const struct in6_addr *prefix, int prefixlen,
284 int ifindex, u32 label, int replace)
285{
286 struct ip6addrlbl_entry *newp;
287 int ret = 0;
288
289 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
290 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
291 replace);
292
293 newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
294 if (IS_ERR(newp))
295 return PTR_ERR(newp);
296 spin_lock(&ip6addrlbl_table.lock);
297 ret = __ip6addrlbl_add(newp, replace);
298 spin_unlock(&ip6addrlbl_table.lock);
299 if (ret)
300 ip6addrlbl_free(newp);
301 return ret;
302}
303
304/* remove a label */
305static int __ip6addrlbl_del(struct net *net,
306 const struct in6_addr *prefix, int prefixlen,
307 int ifindex)
308{
309 struct ip6addrlbl_entry *p = NULL;
310 struct hlist_node *pos, *n;
311 int ret = -ESRCH;
312
313 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
314 __func__, prefix, prefixlen, ifindex);
315
316 hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
317 if (p->prefixlen == prefixlen &&
318 net_eq(ip6addrlbl_net(p), net) &&
319 p->ifindex == ifindex &&
320 ipv6_addr_equal(&p->prefix, prefix)) {
321 hlist_del_rcu(&p->list);
322 ip6addrlbl_put(p);
323 ret = 0;
324 break;
325 }
326 }
327 return ret;
328}
329
330static int ip6addrlbl_del(struct net *net,
331 const struct in6_addr *prefix, int prefixlen,
332 int ifindex)
333{
334 struct in6_addr prefix_buf;
335 int ret;
336
337 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
338 __func__, prefix, prefixlen, ifindex);
339
340 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
341 spin_lock(&ip6addrlbl_table.lock);
342 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
343 spin_unlock(&ip6addrlbl_table.lock);
344 return ret;
345}
346
347/* add default label */
348static int __net_init ip6addrlbl_net_init(struct net *net)
349{
350 int err = 0;
351 int i;
352
353 ADDRLABEL(KERN_DEBUG "%s()\n", __func__);
354
355 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
356 int ret = ip6addrlbl_add(net,
357 ip6addrlbl_init_table[i].prefix,
358 ip6addrlbl_init_table[i].prefixlen,
359 0,
360 ip6addrlbl_init_table[i].label, 0);
361 /* XXX: should we free all rules when we catch an error? */
362 if (ret && (!err || err != -ENOMEM))
363 err = ret;
364 }
365 return err;
366}
367
368static void __net_exit ip6addrlbl_net_exit(struct net *net)
369{
370 struct ip6addrlbl_entry *p = NULL;
371 struct hlist_node *pos, *n;
372
373 /* Remove all labels belonging to the exiting net */
374 spin_lock(&ip6addrlbl_table.lock);
375 hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
376 if (net_eq(ip6addrlbl_net(p), net)) {
377 hlist_del_rcu(&p->list);
378 ip6addrlbl_put(p);
379 }
380 }
381 spin_unlock(&ip6addrlbl_table.lock);
382}
383
384static struct pernet_operations ipv6_addr_label_ops = {
385 .init = ip6addrlbl_net_init,
386 .exit = ip6addrlbl_net_exit,
387};
388
389int __init ipv6_addr_label_init(void)
390{
391 spin_lock_init(&ip6addrlbl_table.lock);
392
393 return register_pernet_subsys(&ipv6_addr_label_ops);
394}
395
396void ipv6_addr_label_cleanup(void)
397{
398 unregister_pernet_subsys(&ipv6_addr_label_ops);
399}
400
401static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
402 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
403 [IFAL_LABEL] = { .len = sizeof(u32), },
404};
405
406static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
407 void *arg)
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
429 pfx = nla_data(tb[IFAL_ADDRESS]);
430 if (!pfx)
431 return -EINVAL;
432
433 if (!tb[IFAL_LABEL])
434 return -EINVAL;
435 label = nla_get_u32(tb[IFAL_LABEL]);
436 if (label == IPV6_ADDR_LABEL_DEFAULT)
437 return -EINVAL;
438
439 switch(nlh->nlmsg_type) {
440 case RTM_NEWADDRLABEL:
441 if (ifal->ifal_index &&
442 !__dev_get_by_index(net, ifal->ifal_index))
443 return -EINVAL;
444
445 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
446 ifal->ifal_index, label,
447 nlh->nlmsg_flags & NLM_F_REPLACE);
448 break;
449 case RTM_DELADDRLABEL:
450 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
451 ifal->ifal_index);
452 break;
453 default:
454 err = -EOPNOTSUPP;
455 }
456 return err;
457}
458
459static inline void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
460 int prefixlen, int ifindex, u32 lseq)
461{
462 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
463 ifal->ifal_family = AF_INET6;
464 ifal->ifal_prefixlen = prefixlen;
465 ifal->ifal_flags = 0;
466 ifal->ifal_index = ifindex;
467 ifal->ifal_seq = lseq;
468};
469
470static int ip6addrlbl_fill(struct sk_buff *skb,
471 struct ip6addrlbl_entry *p,
472 u32 lseq,
473 u32 pid, u32 seq, int event,
474 unsigned int flags)
475{
476 struct nlmsghdr *nlh = nlmsg_put(skb, pid, seq, event,
477 sizeof(struct ifaddrlblmsg), flags);
478 if (!nlh)
479 return -EMSGSIZE;
480
481 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
482
483 if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 ||
484 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
485 nlmsg_cancel(skb, nlh);
486 return -EMSGSIZE;
487 }
488
489 return nlmsg_end(skb, nlh);
490}
491
492static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
493{
494 struct net *net = sock_net(skb->sk);
495 struct ip6addrlbl_entry *p;
496 struct hlist_node *pos;
497 int idx = 0, s_idx = cb->args[0];
498 int err;
499
500 rcu_read_lock();
501 hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
502 if (idx >= s_idx &&
503 net_eq(ip6addrlbl_net(p), net)) {
504 if ((err = ip6addrlbl_fill(skb, p,
505 ip6addrlbl_table.seq,
506 NETLINK_CB(cb->skb).pid,
507 cb->nlh->nlmsg_seq,
508 RTM_NEWADDRLABEL,
509 NLM_F_MULTI)) <= 0)
510 break;
511 }
512 idx++;
513 }
514 rcu_read_unlock();
515 cb->args[0] = idx;
516 return skb->len;
517}
518
519static inline int ip6addrlbl_msgsize(void)
520{
521 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
522 + nla_total_size(16) /* IFAL_ADDRESS */
523 + nla_total_size(4); /* IFAL_LABEL */
524}
525
526static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
527 void *arg)
528{
529 struct net *net = sock_net(in_skb->sk);
530 struct ifaddrlblmsg *ifal;
531 struct nlattr *tb[IFAL_MAX+1];
532 struct in6_addr *addr;
533 u32 lseq;
534 int err = 0;
535 struct ip6addrlbl_entry *p;
536 struct sk_buff *skb;
537
538 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
539 if (err < 0)
540 return err;
541
542 ifal = nlmsg_data(nlh);
543
544 if (ifal->ifal_family != AF_INET6 ||
545 ifal->ifal_prefixlen != 128)
546 return -EINVAL;
547
548 if (ifal->ifal_index &&
549 !__dev_get_by_index(net, ifal->ifal_index))
550 return -EINVAL;
551
552 if (!tb[IFAL_ADDRESS])
553 return -EINVAL;
554
555 addr = nla_data(tb[IFAL_ADDRESS]);
556 if (!addr)
557 return -EINVAL;
558
559 rcu_read_lock();
560 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
561 if (p && ip6addrlbl_hold(p))
562 p = NULL;
563 lseq = ip6addrlbl_table.seq;
564 rcu_read_unlock();
565
566 if (!p) {
567 err = -ESRCH;
568 goto out;
569 }
570
571 if (!(skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL))) {
572 ip6addrlbl_put(p);
573 return -ENOBUFS;
574 }
575
576 err = ip6addrlbl_fill(skb, p, lseq,
577 NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
578 RTM_NEWADDRLABEL, 0);
579
580 ip6addrlbl_put(p);
581
582 if (err < 0) {
583 WARN_ON(err == -EMSGSIZE);
584 kfree_skb(skb);
585 goto out;
586 }
587
588 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
589out:
590 return err;
591}
592
593void __init ipv6_addr_label_rtnl_register(void)
594{
595 __rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel,
596 NULL, NULL);
597 __rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel,
598 NULL, NULL);
599 __rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get,
600 ip6addrlbl_dump, NULL);
601}
602
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