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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
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}
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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 {
86 .prefix = &in6addr_any,
87 .label = 1,
88 }, {
89 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
90 .prefixlen = 7,
91 .label = 5,
92 }, {
93 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
94 .prefixlen = 10,
95 .label = 11,
96 }, {
97 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
98 .prefixlen = 16,
99 .label = 2,
100 }, {
101 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
102 .prefixlen = 16,
103 .label = 12,
104 }, {
105 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
106 .prefixlen = 32,
107 .label = 6,
108 }, {
109 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
110 .prefixlen = 28,
111 .label = 7,
112 }, {
113 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
114 .prefixlen = 96,
115 .label = 4,
116 }, {
117 .prefix = &in6addr_any,
118 .prefixlen = 96,
119 .label = 3,
120 }, {
121 .prefix = &in6addr_loopback,
122 .prefixlen = 128,
123 .label = 0,
124 }
125};
126
127
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
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
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
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
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
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
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
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
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)
521 + nla_total_size(4);
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
598
