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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 <net/addrconf.h>
17#include <linux/if_addrlabel.h>
18#include <linux/netlink.h>
19#include <linux/rtnetlink.h>
20
21#if 0
22#define ADDRLABEL(x...) printk(x)
23#else
24#define ADDRLABEL(x...) do { ; } while(0)
25#endif
26
27
28
29
30struct ip6addrlbl_entry
31{
32#ifdef CONFIG_NET_NS
33 struct net *lbl_net;
34#endif
35 struct in6_addr prefix;
36 int prefixlen;
37 int ifindex;
38 int addrtype;
39 u32 label;
40 struct hlist_node list;
41 atomic_t refcnt;
42 struct rcu_head rcu;
43};
44
45static struct ip6addrlbl_table
46{
47 struct hlist_head head;
48 spinlock_t lock;
49 u32 seq;
50} ip6addrlbl_table;
51
52static inline
53struct net *ip6addrlbl_net(const struct ip6addrlbl_entry *lbl)
54{
55#ifdef CONFIG_NET_NS
56 return lbl->lbl_net;
57#else
58 return &init_net;
59#endif
60}
61
62
63
64
65
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76
77
78
79#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
80
81static const __net_initdata struct ip6addrlbl_init_table
82{
83 const struct in6_addr *prefix;
84 int prefixlen;
85 u32 label;
86} ip6addrlbl_init_table[] = {
87 {
88 .prefix = &in6addr_any,
89 .label = 1,
90 },{
91 .prefix = &(struct in6_addr){{{ 0xfc }}},
92 .prefixlen = 7,
93 .label = 5,
94 },{
95 .prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
96 .prefixlen = 16,
97 .label = 2,
98 },{
99 .prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
100 .prefixlen = 32,
101 .label = 6,
102 },{
103 .prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
104 .prefixlen = 28,
105 .label = 7,
106 },{
107 .prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
108 .prefixlen = 96,
109 .label = 4,
110 },{
111 .prefix = &in6addr_any,
112 .prefixlen = 96,
113 .label = 3,
114 },{
115 .prefix = &in6addr_loopback,
116 .prefixlen = 128,
117 .label = 0,
118 }
119};
120
121
122static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
123{
124#ifdef CONFIG_NET_NS
125 release_net(p->lbl_net);
126#endif
127 kfree(p);
128}
129
130static void ip6addrlbl_free_rcu(struct rcu_head *h)
131{
132 ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
133}
134
135static inline int ip6addrlbl_hold(struct ip6addrlbl_entry *p)
136{
137 return atomic_inc_not_zero(&p->refcnt);
138}
139
140static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
141{
142 if (atomic_dec_and_test(&p->refcnt))
143 call_rcu(&p->rcu, ip6addrlbl_free_rcu);
144}
145
146
147static int __ip6addrlbl_match(struct net *net,
148 struct ip6addrlbl_entry *p,
149 const struct in6_addr *addr,
150 int addrtype, int ifindex)
151{
152 if (!net_eq(ip6addrlbl_net(p), net))
153 return 0;
154 if (p->ifindex && p->ifindex != ifindex)
155 return 0;
156 if (p->addrtype && p->addrtype != addrtype)
157 return 0;
158 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
159 return 0;
160 return 1;
161}
162
163static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
164 const struct in6_addr *addr,
165 int type, int ifindex)
166{
167 struct hlist_node *pos;
168 struct ip6addrlbl_entry *p;
169 hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
170 if (__ip6addrlbl_match(net, p, addr, type, ifindex))
171 return p;
172 }
173 return NULL;
174}
175
176u32 ipv6_addr_label(struct net *net,
177 const struct in6_addr *addr, int type, int ifindex)
178{
179 u32 label;
180 struct ip6addrlbl_entry *p;
181
182 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
183
184 rcu_read_lock();
185 p = __ipv6_addr_label(net, addr, type, ifindex);
186 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
187 rcu_read_unlock();
188
189 ADDRLABEL(KERN_DEBUG "%s(addr=" NIP6_FMT ", type=%d, ifindex=%d) => %08x\n",
190 __func__,
191 NIP6(*addr), type, ifindex,
192 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=" NIP6_FMT ", prefixlen=%d, ifindex=%d, label=%u)\n",
207 __func__,
208 NIP6(*prefix), prefixlen,
209 ifindex,
210 (unsigned int)label);
211
212 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
213
214 switch (addrtype) {
215 case IPV6_ADDR_MAPPED:
216 if (prefixlen > 96)
217 return ERR_PTR(-EINVAL);
218 if (prefixlen < 96)
219 addrtype = 0;
220 break;
221 case IPV6_ADDR_COMPATv4:
222 if (prefixlen != 96)
223 addrtype = 0;
224 break;
225 case IPV6_ADDR_LOOPBACK:
226 if (prefixlen != 128)
227 addrtype = 0;
228 break;
229 }
230
231 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
232 if (!newp)
233 return ERR_PTR(-ENOMEM);
234
235 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
236 newp->prefixlen = prefixlen;
237 newp->ifindex = ifindex;
238 newp->addrtype = addrtype;
239 newp->label = label;
240 INIT_HLIST_NODE(&newp->list);
241#ifdef CONFIG_NET_NS
242 newp->lbl_net = hold_net(net);
243#endif
244 atomic_set(&newp->refcnt, 1);
245 return newp;
246}
247
248
249static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
250{
251 int ret = 0;
252
253 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n",
254 __func__,
255 newp, replace);
256
257 if (hlist_empty(&ip6addrlbl_table.head)) {
258 hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
259 } else {
260 struct hlist_node *pos, *n;
261 struct ip6addrlbl_entry *p = NULL;
262 hlist_for_each_entry_safe(p, pos, n,
263 &ip6addrlbl_table.head, list) {
264 if (p->prefixlen == newp->prefixlen &&
265 net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
266 p->ifindex == newp->ifindex &&
267 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
268 if (!replace) {
269 ret = -EEXIST;
270 goto out;
271 }
272 hlist_replace_rcu(&p->list, &newp->list);
273 ip6addrlbl_put(p);
274 goto out;
275 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
276 (p->prefixlen < newp->prefixlen)) {
277 hlist_add_before_rcu(&newp->list, &p->list);
278 goto out;
279 }
280 }
281 hlist_add_after_rcu(&p->list, &newp->list);
282 }
283out:
284 if (!ret)
285 ip6addrlbl_table.seq++;
286 return ret;
287}
288
289
290static int ip6addrlbl_add(struct net *net,
291 const struct in6_addr *prefix, int prefixlen,
292 int ifindex, u32 label, int replace)
293{
294 struct ip6addrlbl_entry *newp;
295 int ret = 0;
296
297 ADDRLABEL(KERN_DEBUG "%s(prefix=" NIP6_FMT ", prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
298 __func__,
299 NIP6(*prefix), prefixlen,
300 ifindex,
301 (unsigned int)label,
302 replace);
303
304 newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
305 if (IS_ERR(newp))
306 return PTR_ERR(newp);
307 spin_lock(&ip6addrlbl_table.lock);
308 ret = __ip6addrlbl_add(newp, replace);
309 spin_unlock(&ip6addrlbl_table.lock);
310 if (ret)
311 ip6addrlbl_free(newp);
312 return ret;
313}
314
315
316static int __ip6addrlbl_del(struct net *net,
317 const struct in6_addr *prefix, int prefixlen,
318 int ifindex)
319{
320 struct ip6addrlbl_entry *p = NULL;
321 struct hlist_node *pos, *n;
322 int ret = -ESRCH;
323
324 ADDRLABEL(KERN_DEBUG "%s(prefix=" NIP6_FMT ", prefixlen=%d, ifindex=%d)\n",
325 __func__,
326 NIP6(*prefix), prefixlen,
327 ifindex);
328
329 hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
330 if (p->prefixlen == prefixlen &&
331 net_eq(ip6addrlbl_net(p), net) &&
332 p->ifindex == ifindex &&
333 ipv6_addr_equal(&p->prefix, prefix)) {
334 hlist_del_rcu(&p->list);
335 ip6addrlbl_put(p);
336 ret = 0;
337 break;
338 }
339 }
340 return ret;
341}
342
343static int ip6addrlbl_del(struct net *net,
344 const struct in6_addr *prefix, int prefixlen,
345 int ifindex)
346{
347 struct in6_addr prefix_buf;
348 int ret;
349
350 ADDRLABEL(KERN_DEBUG "%s(prefix=" NIP6_FMT ", prefixlen=%d, ifindex=%d)\n",
351 __func__,
352 NIP6(*prefix), prefixlen,
353 ifindex);
354
355 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
356 spin_lock(&ip6addrlbl_table.lock);
357 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
358 spin_unlock(&ip6addrlbl_table.lock);
359 return ret;
360}
361
362
363static int __net_init ip6addrlbl_net_init(struct net *net)
364{
365 int err = 0;
366 int i;
367
368 ADDRLABEL(KERN_DEBUG "%s()\n", __func__);
369
370 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
371 int ret = ip6addrlbl_add(net,
372 ip6addrlbl_init_table[i].prefix,
373 ip6addrlbl_init_table[i].prefixlen,
374 0,
375 ip6addrlbl_init_table[i].label, 0);
376
377 if (ret && (!err || err != -ENOMEM))
378 err = ret;
379 }
380 return err;
381}
382
383static void __net_exit ip6addrlbl_net_exit(struct net *net)
384{
385 struct ip6addrlbl_entry *p = NULL;
386 struct hlist_node *pos, *n;
387
388
389 spin_lock(&ip6addrlbl_table.lock);
390 hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
391 if (net_eq(ip6addrlbl_net(p), net)) {
392 hlist_del_rcu(&p->list);
393 ip6addrlbl_put(p);
394 }
395 }
396 spin_unlock(&ip6addrlbl_table.lock);
397}
398
399static struct pernet_operations ipv6_addr_label_ops = {
400 .init = ip6addrlbl_net_init,
401 .exit = ip6addrlbl_net_exit,
402};
403
404int __init ipv6_addr_label_init(void)
405{
406 spin_lock_init(&ip6addrlbl_table.lock);
407
408 return register_pernet_subsys(&ipv6_addr_label_ops);
409}
410
411static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
412 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
413 [IFAL_LABEL] = { .len = sizeof(u32), },
414};
415
416static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
417 void *arg)
418{
419 struct net *net = sock_net(skb->sk);
420 struct ifaddrlblmsg *ifal;
421 struct nlattr *tb[IFAL_MAX+1];
422 struct in6_addr *pfx;
423 u32 label;
424 int err = 0;
425
426 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
427 if (err < 0)
428 return err;
429
430 ifal = nlmsg_data(nlh);
431
432 if (ifal->ifal_family != AF_INET6 ||
433 ifal->ifal_prefixlen > 128)
434 return -EINVAL;
435
436 if (ifal->ifal_index &&
437 !__dev_get_by_index(net, ifal->ifal_index))
438 return -EINVAL;
439
440 if (!tb[IFAL_ADDRESS])
441 return -EINVAL;
442
443 pfx = nla_data(tb[IFAL_ADDRESS]);
444 if (!pfx)
445 return -EINVAL;
446
447 if (!tb[IFAL_LABEL])
448 return -EINVAL;
449 label = nla_get_u32(tb[IFAL_LABEL]);
450 if (label == IPV6_ADDR_LABEL_DEFAULT)
451 return -EINVAL;
452
453 switch(nlh->nlmsg_type) {
454 case RTM_NEWADDRLABEL:
455 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
456 ifal->ifal_index, label,
457 nlh->nlmsg_flags & NLM_F_REPLACE);
458 break;
459 case RTM_DELADDRLABEL:
460 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
461 ifal->ifal_index);
462 break;
463 default:
464 err = -EOPNOTSUPP;
465 }
466 return err;
467}
468
469static inline void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
470 int prefixlen, int ifindex, u32 lseq)
471{
472 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
473 ifal->ifal_family = AF_INET6;
474 ifal->ifal_prefixlen = prefixlen;
475 ifal->ifal_flags = 0;
476 ifal->ifal_index = ifindex;
477 ifal->ifal_seq = lseq;
478};
479
480static int ip6addrlbl_fill(struct sk_buff *skb,
481 struct ip6addrlbl_entry *p,
482 u32 lseq,
483 u32 pid, u32 seq, int event,
484 unsigned int flags)
485{
486 struct nlmsghdr *nlh = nlmsg_put(skb, pid, seq, event,
487 sizeof(struct ifaddrlblmsg), flags);
488 if (!nlh)
489 return -EMSGSIZE;
490
491 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
492
493 if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 ||
494 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
495 nlmsg_cancel(skb, nlh);
496 return -EMSGSIZE;
497 }
498
499 return nlmsg_end(skb, nlh);
500}
501
502static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
503{
504 struct net *net = sock_net(skb->sk);
505 struct ip6addrlbl_entry *p;
506 struct hlist_node *pos;
507 int idx = 0, s_idx = cb->args[0];
508 int err;
509
510 rcu_read_lock();
511 hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
512 if (idx >= s_idx &&
513 net_eq(ip6addrlbl_net(p), net)) {
514 if ((err = ip6addrlbl_fill(skb, p,
515 ip6addrlbl_table.seq,
516 NETLINK_CB(cb->skb).pid,
517 cb->nlh->nlmsg_seq,
518 RTM_NEWADDRLABEL,
519 NLM_F_MULTI)) <= 0)
520 break;
521 }
522 idx++;
523 }
524 rcu_read_unlock();
525 cb->args[0] = idx;
526 return skb->len;
527}
528
529static inline int ip6addrlbl_msgsize(void)
530{
531 return (NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
532 + nla_total_size(16)
533 + nla_total_size(4)
534 );
535}
536
537static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
538 void *arg)
539{
540 struct net *net = sock_net(in_skb->sk);
541 struct ifaddrlblmsg *ifal;
542 struct nlattr *tb[IFAL_MAX+1];
543 struct in6_addr *addr;
544 u32 lseq;
545 int err = 0;
546 struct ip6addrlbl_entry *p;
547 struct sk_buff *skb;
548
549 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
550 if (err < 0)
551 return err;
552
553 ifal = nlmsg_data(nlh);
554
555 if (ifal->ifal_family != AF_INET6 ||
556 ifal->ifal_prefixlen != 128)
557 return -EINVAL;
558
559 if (ifal->ifal_index &&
560 !__dev_get_by_index(net, ifal->ifal_index))
561 return -EINVAL;
562
563 if (!tb[IFAL_ADDRESS])
564 return -EINVAL;
565
566 addr = nla_data(tb[IFAL_ADDRESS]);
567 if (!addr)
568 return -EINVAL;
569
570 rcu_read_lock();
571 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
572 if (p && ip6addrlbl_hold(p))
573 p = NULL;
574 lseq = ip6addrlbl_table.seq;
575 rcu_read_unlock();
576
577 if (!p) {
578 err = -ESRCH;
579 goto out;
580 }
581
582 if (!(skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL))) {
583 ip6addrlbl_put(p);
584 return -ENOBUFS;
585 }
586
587 err = ip6addrlbl_fill(skb, p, lseq,
588 NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
589 RTM_NEWADDRLABEL, 0);
590
591 ip6addrlbl_put(p);
592
593 if (err < 0) {
594 WARN_ON(err == -EMSGSIZE);
595 kfree_skb(skb);
596 goto out;
597 }
598
599 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
600out:
601 return err;
602}
603
604void __init ipv6_addr_label_rtnl_register(void)
605{
606 __rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel, NULL);
607 __rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel, NULL);
608 __rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get, ip6addrlbl_dump);
609}
610
611
