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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{
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
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79
80#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
81
82static const __net_initconst struct ip6addrlbl_init_table
83{
84 const struct in6_addr *prefix;
85 int prefixlen;
86 u32 label;
87} ip6addrlbl_init_table[] = {
88 {
89 .prefix = &in6addr_any,
90 .label = 1,
91 },{
92 .prefix = &(struct in6_addr){{{ 0xfc }}},
93 .prefixlen = 7,
94 .label = 5,
95 },{
96 .prefix = &(struct in6_addr){{{ 0xfe, 0xc0 }}},
97 .prefixlen = 10,
98 .label = 11,
99 },{
100 .prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
101 .prefixlen = 16,
102 .label = 2,
103 },{
104 .prefix = &(struct in6_addr){{{ 0x3f, 0xfe }}},
105 .prefixlen = 16,
106 .label = 12,
107 },{
108 .prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
109 .prefixlen = 32,
110 .label = 6,
111 },{
112 .prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
113 .prefixlen = 28,
114 .label = 7,
115 },{
116 .prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
117 .prefixlen = 96,
118 .label = 4,
119 },{
120 .prefix = &in6addr_any,
121 .prefixlen = 96,
122 .label = 3,
123 },{
124 .prefix = &in6addr_loopback,
125 .prefixlen = 128,
126 .label = 0,
127 }
128};
129
130
131static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
132{
133#ifdef CONFIG_NET_NS
134 release_net(p->lbl_net);
135#endif
136 kfree(p);
137}
138
139static void ip6addrlbl_free_rcu(struct rcu_head *h)
140{
141 ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
142}
143
144static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p)
145{
146 return atomic_inc_not_zero(&p->refcnt);
147}
148
149static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
150{
151 if (atomic_dec_and_test(&p->refcnt))
152 call_rcu(&p->rcu, ip6addrlbl_free_rcu);
153}
154
155
156static bool __ip6addrlbl_match(struct net *net,
157 const struct ip6addrlbl_entry *p,
158 const struct in6_addr *addr,
159 int addrtype, int ifindex)
160{
161 if (!net_eq(ip6addrlbl_net(p), net))
162 return false;
163 if (p->ifindex && p->ifindex != ifindex)
164 return false;
165 if (p->addrtype && p->addrtype != addrtype)
166 return false;
167 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
168 return false;
169 return true;
170}
171
172static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
173 const struct in6_addr *addr,
174 int type, int ifindex)
175{
176 struct ip6addrlbl_entry *p;
177 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
178 if (__ip6addrlbl_match(net, p, addr, type, ifindex))
179 return p;
180 }
181 return NULL;
182}
183
184u32 ipv6_addr_label(struct net *net,
185 const struct in6_addr *addr, int type, int ifindex)
186{
187 u32 label;
188 struct ip6addrlbl_entry *p;
189
190 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
191
192 rcu_read_lock();
193 p = __ipv6_addr_label(net, addr, type, ifindex);
194 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
195 rcu_read_unlock();
196
197 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
198 __func__, addr, type, ifindex, label);
199
200 return label;
201}
202
203
204static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net,
205 const struct in6_addr *prefix,
206 int prefixlen, int ifindex,
207 u32 label)
208{
209 struct ip6addrlbl_entry *newp;
210 int addrtype;
211
212 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
213 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
214
215 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
216
217 switch (addrtype) {
218 case IPV6_ADDR_MAPPED:
219 if (prefixlen > 96)
220 return ERR_PTR(-EINVAL);
221 if (prefixlen < 96)
222 addrtype = 0;
223 break;
224 case IPV6_ADDR_COMPATv4:
225 if (prefixlen != 96)
226 addrtype = 0;
227 break;
228 case IPV6_ADDR_LOOPBACK:
229 if (prefixlen != 128)
230 addrtype = 0;
231 break;
232 }
233
234 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
235 if (!newp)
236 return ERR_PTR(-ENOMEM);
237
238 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
239 newp->prefixlen = prefixlen;
240 newp->ifindex = ifindex;
241 newp->addrtype = addrtype;
242 newp->label = label;
243 INIT_HLIST_NODE(&newp->list);
244#ifdef CONFIG_NET_NS
245 newp->lbl_net = hold_net(net);
246#endif
247 atomic_set(&newp->refcnt, 1);
248 return newp;
249}
250
251
252static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
253{
254 struct hlist_node *n;
255 struct ip6addrlbl_entry *last = NULL, *p = NULL;
256 int ret = 0;
257
258 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
259 replace);
260
261 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
262 if (p->prefixlen == newp->prefixlen &&
263 net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
264 p->ifindex == newp->ifindex &&
265 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
266 if (!replace) {
267 ret = -EEXIST;
268 goto out;
269 }
270 hlist_replace_rcu(&p->list, &newp->list);
271 ip6addrlbl_put(p);
272 goto out;
273 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
274 (p->prefixlen < newp->prefixlen)) {
275 hlist_add_before_rcu(&newp->list, &p->list);
276 goto out;
277 }
278 last = p;
279 }
280 if (last)
281 hlist_add_after_rcu(&last->list, &newp->list);
282 else
283 hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
284out:
285 if (!ret)
286 ip6addrlbl_table.seq++;
287 return ret;
288}
289
290
291static int ip6addrlbl_add(struct net *net,
292 const struct in6_addr *prefix, int prefixlen,
293 int ifindex, u32 label, int replace)
294{
295 struct ip6addrlbl_entry *newp;
296 int ret = 0;
297
298 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
299 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
300 replace);
301
302 newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
303 if (IS_ERR(newp))
304 return PTR_ERR(newp);
305 spin_lock(&ip6addrlbl_table.lock);
306 ret = __ip6addrlbl_add(newp, replace);
307 spin_unlock(&ip6addrlbl_table.lock);
308 if (ret)
309 ip6addrlbl_free(newp);
310 return ret;
311}
312
313
314static int __ip6addrlbl_del(struct net *net,
315 const struct in6_addr *prefix, int prefixlen,
316 int ifindex)
317{
318 struct ip6addrlbl_entry *p = NULL;
319 struct hlist_node *n;
320 int ret = -ESRCH;
321
322 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
323 __func__, prefix, prefixlen, ifindex);
324
325 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
326 if (p->prefixlen == prefixlen &&
327 net_eq(ip6addrlbl_net(p), net) &&
328 p->ifindex == ifindex &&
329 ipv6_addr_equal(&p->prefix, prefix)) {
330 hlist_del_rcu(&p->list);
331 ip6addrlbl_put(p);
332 ret = 0;
333 break;
334 }
335 }
336 return ret;
337}
338
339static int ip6addrlbl_del(struct net *net,
340 const struct in6_addr *prefix, int prefixlen,
341 int ifindex)
342{
343 struct in6_addr prefix_buf;
344 int ret;
345
346 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
347 __func__, prefix, prefixlen, ifindex);
348
349 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
350 spin_lock(&ip6addrlbl_table.lock);
351 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
352 spin_unlock(&ip6addrlbl_table.lock);
353 return ret;
354}
355
356
357static int __net_init ip6addrlbl_net_init(struct net *net)
358{
359 int err = 0;
360 int i;
361
362 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
363
364 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
365 int ret = ip6addrlbl_add(net,
366 ip6addrlbl_init_table[i].prefix,
367 ip6addrlbl_init_table[i].prefixlen,
368 0,
369 ip6addrlbl_init_table[i].label, 0);
370
371 if (ret && (!err || err != -ENOMEM))
372 err = ret;
373 }
374 return err;
375}
376
377static void __net_exit ip6addrlbl_net_exit(struct net *net)
378{
379 struct ip6addrlbl_entry *p = NULL;
380 struct hlist_node *n;
381
382
383 spin_lock(&ip6addrlbl_table.lock);
384 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
385 if (net_eq(ip6addrlbl_net(p), net)) {
386 hlist_del_rcu(&p->list);
387 ip6addrlbl_put(p);
388 }
389 }
390 spin_unlock(&ip6addrlbl_table.lock);
391}
392
393static struct pernet_operations ipv6_addr_label_ops = {
394 .init = ip6addrlbl_net_init,
395 .exit = ip6addrlbl_net_exit,
396};
397
398int __init ipv6_addr_label_init(void)
399{
400 spin_lock_init(&ip6addrlbl_table.lock);
401
402 return register_pernet_subsys(&ipv6_addr_label_ops);
403}
404
405void ipv6_addr_label_cleanup(void)
406{
407 unregister_pernet_subsys(&ipv6_addr_label_ops);
408}
409
410static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
411 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
412 [IFAL_LABEL] = { .len = sizeof(u32), },
413};
414
415static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh)
416{
417 struct net *net = sock_net(skb->sk);
418 struct ifaddrlblmsg *ifal;
419 struct nlattr *tb[IFAL_MAX+1];
420 struct in6_addr *pfx;
421 u32 label;
422 int err = 0;
423
424 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
425 if (err < 0)
426 return err;
427
428 ifal = nlmsg_data(nlh);
429
430 if (ifal->ifal_family != AF_INET6 ||
431 ifal->ifal_prefixlen > 128)
432 return -EINVAL;
433
434 if (!tb[IFAL_ADDRESS])
435 return -EINVAL;
436 pfx = nla_data(tb[IFAL_ADDRESS]);
437
438 if (!tb[IFAL_LABEL])
439 return -EINVAL;
440 label = nla_get_u32(tb[IFAL_LABEL]);
441 if (label == IPV6_ADDR_LABEL_DEFAULT)
442 return -EINVAL;
443
444 switch(nlh->nlmsg_type) {
445 case RTM_NEWADDRLABEL:
446 if (ifal->ifal_index &&
447 !__dev_get_by_index(net, ifal->ifal_index))
448 return -EINVAL;
449
450 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
451 ifal->ifal_index, label,
452 nlh->nlmsg_flags & NLM_F_REPLACE);
453 break;
454 case RTM_DELADDRLABEL:
455 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
456 ifal->ifal_index);
457 break;
458 default:
459 err = -EOPNOTSUPP;
460 }
461 return err;
462}
463
464static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
465 int prefixlen, int ifindex, u32 lseq)
466{
467 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
468 ifal->ifal_family = AF_INET6;
469 ifal->ifal_prefixlen = prefixlen;
470 ifal->ifal_flags = 0;
471 ifal->ifal_index = ifindex;
472 ifal->ifal_seq = lseq;
473};
474
475static int ip6addrlbl_fill(struct sk_buff *skb,
476 struct ip6addrlbl_entry *p,
477 u32 lseq,
478 u32 portid, u32 seq, int event,
479 unsigned int flags)
480{
481 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
482 sizeof(struct ifaddrlblmsg), flags);
483 if (!nlh)
484 return -EMSGSIZE;
485
486 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
487
488 if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 ||
489 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
490 nlmsg_cancel(skb, nlh);
491 return -EMSGSIZE;
492 }
493
494 return nlmsg_end(skb, nlh);
495}
496
497static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
498{
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;
503
504 rcu_read_lock();
505 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
506 if (idx >= s_idx &&
507 net_eq(ip6addrlbl_net(p), net)) {
508 if ((err = ip6addrlbl_fill(skb, p,
509 ip6addrlbl_table.seq,
510 NETLINK_CB(cb->skb).portid,
511 cb->nlh->nlmsg_seq,
512 RTM_NEWADDRLABEL,
513 NLM_F_MULTI)) <= 0)
514 break;
515 }
516 idx++;
517 }
518 rcu_read_unlock();
519 cb->args[0] = idx;
520 return skb->len;
521}
522
523static inline int ip6addrlbl_msgsize(void)
524{
525 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
526 + nla_total_size(16)
527 + nla_total_size(4);
528}
529
530static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh)
531{
532 struct net *net = sock_net(in_skb->sk);
533 struct ifaddrlblmsg *ifal;
534 struct nlattr *tb[IFAL_MAX+1];
535 struct in6_addr *addr;
536 u32 lseq;
537 int err = 0;
538 struct ip6addrlbl_entry *p;
539 struct sk_buff *skb;
540
541 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
542 if (err < 0)
543 return err;
544
545 ifal = nlmsg_data(nlh);
546
547 if (ifal->ifal_family != AF_INET6 ||
548 ifal->ifal_prefixlen != 128)
549 return -EINVAL;
550
551 if (ifal->ifal_index &&
552 !__dev_get_by_index(net, ifal->ifal_index))
553 return -EINVAL;
554
555 if (!tb[IFAL_ADDRESS])
556 return -EINVAL;
557 addr = nla_data(tb[IFAL_ADDRESS]);
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).portid, 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).portid);
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
603
