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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 int ret = 0;
255
256 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n",
257 __func__,
258 newp, replace);
259
260 if (hlist_empty(&ip6addrlbl_table.head)) {
261 hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
262 } else {
263 struct hlist_node *n;
264 struct ip6addrlbl_entry *p = NULL;
265 hlist_for_each_entry_safe(p, n,
266 &ip6addrlbl_table.head, list) {
267 if (p->prefixlen == newp->prefixlen &&
268 net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
269 p->ifindex == newp->ifindex &&
270 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
271 if (!replace) {
272 ret = -EEXIST;
273 goto out;
274 }
275 hlist_replace_rcu(&p->list, &newp->list);
276 ip6addrlbl_put(p);
277 goto out;
278 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
279 (p->prefixlen < newp->prefixlen)) {
280 hlist_add_before_rcu(&newp->list, &p->list);
281 goto out;
282 }
283 }
284 hlist_add_after_rcu(&p->list, &newp->list);
285 }
286out:
287 if (!ret)
288 ip6addrlbl_table.seq++;
289 return ret;
290}
291
292
293static int ip6addrlbl_add(struct net *net,
294 const struct in6_addr *prefix, int prefixlen,
295 int ifindex, u32 label, int replace)
296{
297 struct ip6addrlbl_entry *newp;
298 int ret = 0;
299
300 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
301 __func__, prefix, prefixlen, ifindex, (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 *n;
322 int ret = -ESRCH;
323
324 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
325 __func__, prefix, prefixlen, ifindex);
326
327 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
328 if (p->prefixlen == prefixlen &&
329 net_eq(ip6addrlbl_net(p), net) &&
330 p->ifindex == ifindex &&
331 ipv6_addr_equal(&p->prefix, prefix)) {
332 hlist_del_rcu(&p->list);
333 ip6addrlbl_put(p);
334 ret = 0;
335 break;
336 }
337 }
338 return ret;
339}
340
341static int ip6addrlbl_del(struct net *net,
342 const struct in6_addr *prefix, int prefixlen,
343 int ifindex)
344{
345 struct in6_addr prefix_buf;
346 int ret;
347
348 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
349 __func__, prefix, prefixlen, ifindex);
350
351 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
352 spin_lock(&ip6addrlbl_table.lock);
353 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
354 spin_unlock(&ip6addrlbl_table.lock);
355 return ret;
356}
357
358
359static int __net_init ip6addrlbl_net_init(struct net *net)
360{
361 int err = 0;
362 int i;
363
364 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
365
366 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
367 int ret = ip6addrlbl_add(net,
368 ip6addrlbl_init_table[i].prefix,
369 ip6addrlbl_init_table[i].prefixlen,
370 0,
371 ip6addrlbl_init_table[i].label, 0);
372
373 if (ret && (!err || err != -ENOMEM))
374 err = ret;
375 }
376 return err;
377}
378
379static void __net_exit ip6addrlbl_net_exit(struct net *net)
380{
381 struct ip6addrlbl_entry *p = NULL;
382 struct hlist_node *n;
383
384
385 spin_lock(&ip6addrlbl_table.lock);
386 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
387 if (net_eq(ip6addrlbl_net(p), net)) {
388 hlist_del_rcu(&p->list);
389 ip6addrlbl_put(p);
390 }
391 }
392 spin_unlock(&ip6addrlbl_table.lock);
393}
394
395static struct pernet_operations ipv6_addr_label_ops = {
396 .init = ip6addrlbl_net_init,
397 .exit = ip6addrlbl_net_exit,
398};
399
400int __init ipv6_addr_label_init(void)
401{
402 spin_lock_init(&ip6addrlbl_table.lock);
403
404 return register_pernet_subsys(&ipv6_addr_label_ops);
405}
406
407void ipv6_addr_label_cleanup(void)
408{
409 unregister_pernet_subsys(&ipv6_addr_label_ops);
410}
411
412static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
413 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
414 [IFAL_LABEL] = { .len = sizeof(u32), },
415};
416
417static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh)
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 (!tb[IFAL_ADDRESS])
437 return -EINVAL;
438 pfx = nla_data(tb[IFAL_ADDRESS]);
439
440 if (!tb[IFAL_LABEL])
441 return -EINVAL;
442 label = nla_get_u32(tb[IFAL_LABEL]);
443 if (label == IPV6_ADDR_LABEL_DEFAULT)
444 return -EINVAL;
445
446 switch(nlh->nlmsg_type) {
447 case RTM_NEWADDRLABEL:
448 if (ifal->ifal_index &&
449 !__dev_get_by_index(net, ifal->ifal_index))
450 return -EINVAL;
451
452 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
453 ifal->ifal_index, label,
454 nlh->nlmsg_flags & NLM_F_REPLACE);
455 break;
456 case RTM_DELADDRLABEL:
457 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
458 ifal->ifal_index);
459 break;
460 default:
461 err = -EOPNOTSUPP;
462 }
463 return err;
464}
465
466static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
467 int prefixlen, int ifindex, u32 lseq)
468{
469 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
470 ifal->ifal_family = AF_INET6;
471 ifal->ifal_prefixlen = prefixlen;
472 ifal->ifal_flags = 0;
473 ifal->ifal_index = ifindex;
474 ifal->ifal_seq = lseq;
475};
476
477static int ip6addrlbl_fill(struct sk_buff *skb,
478 struct ip6addrlbl_entry *p,
479 u32 lseq,
480 u32 portid, u32 seq, int event,
481 unsigned int flags)
482{
483 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
484 sizeof(struct ifaddrlblmsg), flags);
485 if (!nlh)
486 return -EMSGSIZE;
487
488 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
489
490 if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 ||
491 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
492 nlmsg_cancel(skb, nlh);
493 return -EMSGSIZE;
494 }
495
496 return nlmsg_end(skb, nlh);
497}
498
499static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
500{
501 struct net *net = sock_net(skb->sk);
502 struct ip6addrlbl_entry *p;
503 int idx = 0, s_idx = cb->args[0];
504 int err;
505
506 rcu_read_lock();
507 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
508 if (idx >= s_idx &&
509 net_eq(ip6addrlbl_net(p), net)) {
510 if ((err = ip6addrlbl_fill(skb, p,
511 ip6addrlbl_table.seq,
512 NETLINK_CB(cb->skb).portid,
513 cb->nlh->nlmsg_seq,
514 RTM_NEWADDRLABEL,
515 NLM_F_MULTI)) <= 0)
516 break;
517 }
518 idx++;
519 }
520 rcu_read_unlock();
521 cb->args[0] = idx;
522 return skb->len;
523}
524
525static inline int ip6addrlbl_msgsize(void)
526{
527 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
528 + nla_total_size(16)
529 + nla_total_size(4);
530}
531
532static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh)
533{
534 struct net *net = sock_net(in_skb->sk);
535 struct ifaddrlblmsg *ifal;
536 struct nlattr *tb[IFAL_MAX+1];
537 struct in6_addr *addr;
538 u32 lseq;
539 int err = 0;
540 struct ip6addrlbl_entry *p;
541 struct sk_buff *skb;
542
543 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
544 if (err < 0)
545 return err;
546
547 ifal = nlmsg_data(nlh);
548
549 if (ifal->ifal_family != AF_INET6 ||
550 ifal->ifal_prefixlen != 128)
551 return -EINVAL;
552
553 if (ifal->ifal_index &&
554 !__dev_get_by_index(net, ifal->ifal_index))
555 return -EINVAL;
556
557 if (!tb[IFAL_ADDRESS])
558 return -EINVAL;
559 addr = nla_data(tb[IFAL_ADDRESS]);
560
561 rcu_read_lock();
562 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
563 if (p && ip6addrlbl_hold(p))
564 p = NULL;
565 lseq = ip6addrlbl_table.seq;
566 rcu_read_unlock();
567
568 if (!p) {
569 err = -ESRCH;
570 goto out;
571 }
572
573 if (!(skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL))) {
574 ip6addrlbl_put(p);
575 return -ENOBUFS;
576 }
577
578 err = ip6addrlbl_fill(skb, p, lseq,
579 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
580 RTM_NEWADDRLABEL, 0);
581
582 ip6addrlbl_put(p);
583
584 if (err < 0) {
585 WARN_ON(err == -EMSGSIZE);
586 kfree_skb(skb);
587 goto out;
588 }
589
590 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
591out:
592 return err;
593}
594
595void __init ipv6_addr_label_rtnl_register(void)
596{
597 __rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel,
598 NULL, NULL);
599 __rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel,
600 NULL, NULL);
601 __rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get,
602 ip6addrlbl_dump, NULL);
603}
604
605
