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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
59
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73
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 {
85 .prefix = &in6addr_any,
86 .label = 1,
87 },{
88 .prefix = &(struct in6_addr){{{ 0xfc }}},
89 .prefixlen = 7,
90 .label = 5,
91 },{
92 .prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
93 .prefixlen = 16,
94 .label = 2,
95 },{
96 .prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
97 .prefixlen = 32,
98 .label = 6,
99 },{
100 .prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
101 .prefixlen = 28,
102 .label = 7,
103 },{
104 .prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
105 .prefixlen = 96,
106 .label = 4,
107 },{
108 .prefix = &in6addr_any,
109 .prefixlen = 96,
110 .label = 3,
111 },{
112 .prefix = &in6addr_loopback,
113 .prefixlen = 128,
114 .label = 0,
115 }
116};
117
118
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
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
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
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
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
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
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
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
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)
523 + nla_total_size(4);
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, NULL);
596 __rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel, NULL);
597 __rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get, ip6addrlbl_dump);
598}
599
600
