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1/*
2 * IPv6 Address Label subsystem
3 * for the IPv6 "Default" Source Address Selection
4 *
5 * Copyright (C)2007 USAGI/WIDE Project
6 */
7/*
8 * Author:
9 * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
10 */
11
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 * Policy Table
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/*
60 * Default policy table (RFC3484 + extensions)
61 *
62 * prefix addr_type label
63 * -------------------------------------------------------------------------
64 * ::1/128 LOOPBACK 0
65 * ::/0 N/A 1
66 * 2002::/16 N/A 2
67 * ::/96 COMPATv4 3
68 * ::ffff:0:0/96 V4MAPPED 4
69 * fc00::/7 N/A 5 ULA (RFC 4193)
70 * 2001::/32 N/A 6 Teredo (RFC 4380)
71 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
72 *
73 * Note: 0xffffffff is used if we do not have any policies.
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 { /* ::/0 */
85 .prefix = &in6addr_any,
86 .label = 1,
87 },{ /* fc00::/7 */
88 .prefix = &(struct in6_addr){{{ 0xfc }}},
89 .prefixlen = 7,
90 .label = 5,
91 },{ /* 2002::/16 */
92 .prefix = &(struct in6_addr){{{ 0x20, 0x02 }}},
93 .prefixlen = 16,
94 .label = 2,
95 },{ /* 2001::/32 */
96 .prefix = &(struct in6_addr){{{ 0x20, 0x01 }}},
97 .prefixlen = 32,
98 .label = 6,
99 },{ /* 2001:10::/28 */
100 .prefix = &(struct in6_addr){{{ 0x20, 0x01, 0x00, 0x10 }}},
101 .prefixlen = 28,
102 .label = 7,
103 },{ /* ::ffff:0:0 */
104 .prefix = &(struct in6_addr){{{ [10] = 0xff, [11] = 0xff }}},
105 .prefixlen = 96,
106 .label = 4,
107 },{ /* ::/96 */
108 .prefix = &in6addr_any,
109 .prefixlen = 96,
110 .label = 3,
111 },{ /* ::1/128 */
112 .prefix = &in6addr_loopback,
113 .prefixlen = 128,
114 .label = 0,
115 }
116};
117
118/* Object management */
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/* Find label */
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/* allocate one entry */
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/* add a label */
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/* add a label */
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/* remove a label */
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/* add default label */
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 /* XXX: should we free all rules when we catch an error? */
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 /* Remove all labels belonging to the exiting net */
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) /* IFAL_ADDRESS */
523 + nla_total_size(4); /* IFAL_LABEL */
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,
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
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * IPv6 Address Label subsystem
4 * for the IPv6 "Default" Source Address Selection
5 *
6 * Copyright (C)2007 USAGI/WIDE Project
7 */
8/*
9 * Author:
10 * YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
11 */
12
13#include <linux/kernel.h>
14#include <linux/list.h>
15#include <linux/rcupdate.h>
16#include <linux/in6.h>
17#include <linux/slab.h>
18#include <net/addrconf.h>
19#include <linux/if_addrlabel.h>
20#include <linux/netlink.h>
21#include <linux/rtnetlink.h>
22
23#if 0
24#define ADDRLABEL(x...) printk(x)
25#else
26#define ADDRLABEL(x...) do { ; } while (0)
27#endif
28
29/*
30 * Policy Table
31 */
32struct ip6addrlbl_entry {
33 struct in6_addr prefix;
34 int prefixlen;
35 int ifindex;
36 int addrtype;
37 u32 label;
38 struct hlist_node list;
39 struct rcu_head rcu;
40};
41
42/*
43 * Default policy table (RFC6724 + extensions)
44 *
45 * prefix addr_type label
46 * -------------------------------------------------------------------------
47 * ::1/128 LOOPBACK 0
48 * ::/0 N/A 1
49 * 2002::/16 N/A 2
50 * ::/96 COMPATv4 3
51 * ::ffff:0:0/96 V4MAPPED 4
52 * fc00::/7 N/A 5 ULA (RFC 4193)
53 * 2001::/32 N/A 6 Teredo (RFC 4380)
54 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
55 * fec0::/10 N/A 11 Site-local
56 * (deprecated by RFC3879)
57 * 3ffe::/16 N/A 12 6bone
58 *
59 * Note: 0xffffffff is used if we do not have any policies.
60 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
61 */
62
63#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
64
65static const __net_initconst struct ip6addrlbl_init_table
66{
67 const struct in6_addr *prefix;
68 int prefixlen;
69 u32 label;
70} ip6addrlbl_init_table[] = {
71 { /* ::/0 */
72 .prefix = &in6addr_any,
73 .label = 1,
74 }, { /* fc00::/7 */
75 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
76 .prefixlen = 7,
77 .label = 5,
78 }, { /* fec0::/10 */
79 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
80 .prefixlen = 10,
81 .label = 11,
82 }, { /* 2002::/16 */
83 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
84 .prefixlen = 16,
85 .label = 2,
86 }, { /* 3ffe::/16 */
87 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
88 .prefixlen = 16,
89 .label = 12,
90 }, { /* 2001::/32 */
91 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
92 .prefixlen = 32,
93 .label = 6,
94 }, { /* 2001:10::/28 */
95 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
96 .prefixlen = 28,
97 .label = 7,
98 }, { /* ::ffff:0:0 */
99 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
100 .prefixlen = 96,
101 .label = 4,
102 }, { /* ::/96 */
103 .prefix = &in6addr_any,
104 .prefixlen = 96,
105 .label = 3,
106 }, { /* ::1/128 */
107 .prefix = &in6addr_loopback,
108 .prefixlen = 128,
109 .label = 0,
110 }
111};
112
113/* Find label */
114static bool __ip6addrlbl_match(const struct ip6addrlbl_entry *p,
115 const struct in6_addr *addr,
116 int addrtype, int ifindex)
117{
118 if (p->ifindex && p->ifindex != ifindex)
119 return false;
120 if (p->addrtype && p->addrtype != addrtype)
121 return false;
122 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
123 return false;
124 return true;
125}
126
127static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
128 const struct in6_addr *addr,
129 int type, int ifindex)
130{
131 struct ip6addrlbl_entry *p;
132
133 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
134 if (__ip6addrlbl_match(p, addr, type, ifindex))
135 return p;
136 }
137 return NULL;
138}
139
140u32 ipv6_addr_label(struct net *net,
141 const struct in6_addr *addr, int type, int ifindex)
142{
143 u32 label;
144 struct ip6addrlbl_entry *p;
145
146 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
147
148 rcu_read_lock();
149 p = __ipv6_addr_label(net, addr, type, ifindex);
150 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
151 rcu_read_unlock();
152
153 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
154 __func__, addr, type, ifindex, label);
155
156 return label;
157}
158
159/* allocate one entry */
160static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
161 int prefixlen, int ifindex,
162 u32 label)
163{
164 struct ip6addrlbl_entry *newp;
165 int addrtype;
166
167 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
168 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
169
170 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
171
172 switch (addrtype) {
173 case IPV6_ADDR_MAPPED:
174 if (prefixlen > 96)
175 return ERR_PTR(-EINVAL);
176 if (prefixlen < 96)
177 addrtype = 0;
178 break;
179 case IPV6_ADDR_COMPATv4:
180 if (prefixlen != 96)
181 addrtype = 0;
182 break;
183 case IPV6_ADDR_LOOPBACK:
184 if (prefixlen != 128)
185 addrtype = 0;
186 break;
187 }
188
189 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
190 if (!newp)
191 return ERR_PTR(-ENOMEM);
192
193 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
194 newp->prefixlen = prefixlen;
195 newp->ifindex = ifindex;
196 newp->addrtype = addrtype;
197 newp->label = label;
198 INIT_HLIST_NODE(&newp->list);
199 return newp;
200}
201
202/* add a label */
203static int __ip6addrlbl_add(struct net *net, struct ip6addrlbl_entry *newp,
204 int replace)
205{
206 struct ip6addrlbl_entry *last = NULL, *p = NULL;
207 struct hlist_node *n;
208 int ret = 0;
209
210 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
211 replace);
212
213 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
214 if (p->prefixlen == newp->prefixlen &&
215 p->ifindex == newp->ifindex &&
216 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
217 if (!replace) {
218 ret = -EEXIST;
219 goto out;
220 }
221 hlist_replace_rcu(&p->list, &newp->list);
222 kfree_rcu(p, rcu);
223 goto out;
224 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
225 (p->prefixlen < newp->prefixlen)) {
226 hlist_add_before_rcu(&newp->list, &p->list);
227 goto out;
228 }
229 last = p;
230 }
231 if (last)
232 hlist_add_behind_rcu(&newp->list, &last->list);
233 else
234 hlist_add_head_rcu(&newp->list, &net->ipv6.ip6addrlbl_table.head);
235out:
236 if (!ret)
237 net->ipv6.ip6addrlbl_table.seq++;
238 return ret;
239}
240
241/* add a label */
242static int ip6addrlbl_add(struct net *net,
243 const struct in6_addr *prefix, int prefixlen,
244 int ifindex, u32 label, int replace)
245{
246 struct ip6addrlbl_entry *newp;
247 int ret = 0;
248
249 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
250 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
251 replace);
252
253 newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
254 if (IS_ERR(newp))
255 return PTR_ERR(newp);
256 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
257 ret = __ip6addrlbl_add(net, newp, replace);
258 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
259 if (ret)
260 kfree(newp);
261 return ret;
262}
263
264/* remove a label */
265static int __ip6addrlbl_del(struct net *net,
266 const struct in6_addr *prefix, int prefixlen,
267 int ifindex)
268{
269 struct ip6addrlbl_entry *p = NULL;
270 struct hlist_node *n;
271 int ret = -ESRCH;
272
273 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
274 __func__, prefix, prefixlen, ifindex);
275
276 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
277 if (p->prefixlen == prefixlen &&
278 p->ifindex == ifindex &&
279 ipv6_addr_equal(&p->prefix, prefix)) {
280 hlist_del_rcu(&p->list);
281 kfree_rcu(p, rcu);
282 ret = 0;
283 break;
284 }
285 }
286 return ret;
287}
288
289static int ip6addrlbl_del(struct net *net,
290 const struct in6_addr *prefix, int prefixlen,
291 int ifindex)
292{
293 struct in6_addr prefix_buf;
294 int ret;
295
296 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
297 __func__, prefix, prefixlen, ifindex);
298
299 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
300 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
301 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
302 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
303 return ret;
304}
305
306/* add default label */
307static int __net_init ip6addrlbl_net_init(struct net *net)
308{
309 int err = 0;
310 int i;
311
312 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
313
314 spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
315 INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
316
317 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
318 int ret = ip6addrlbl_add(net,
319 ip6addrlbl_init_table[i].prefix,
320 ip6addrlbl_init_table[i].prefixlen,
321 0,
322 ip6addrlbl_init_table[i].label, 0);
323 /* XXX: should we free all rules when we catch an error? */
324 if (ret && (!err || err != -ENOMEM))
325 err = ret;
326 }
327 return err;
328}
329
330static void __net_exit ip6addrlbl_net_exit(struct net *net)
331{
332 struct ip6addrlbl_entry *p = NULL;
333 struct hlist_node *n;
334
335 /* Remove all labels belonging to the exiting net */
336 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
337 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
338 hlist_del_rcu(&p->list);
339 kfree_rcu(p, rcu);
340 }
341 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
342}
343
344static struct pernet_operations ipv6_addr_label_ops = {
345 .init = ip6addrlbl_net_init,
346 .exit = ip6addrlbl_net_exit,
347};
348
349int __init ipv6_addr_label_init(void)
350{
351 return register_pernet_subsys(&ipv6_addr_label_ops);
352}
353
354void ipv6_addr_label_cleanup(void)
355{
356 unregister_pernet_subsys(&ipv6_addr_label_ops);
357}
358
359static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
360 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
361 [IFAL_LABEL] = { .len = sizeof(u32), },
362};
363
364static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
365{
366
367 struct net_device *dev;
368
369 rcu_read_lock();
370 dev = dev_get_by_index_rcu(net, ifindex);
371 rcu_read_unlock();
372
373 return dev != NULL;
374}
375
376static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
377 struct netlink_ext_ack *extack)
378{
379 struct net *net = sock_net(skb->sk);
380 struct ifaddrlblmsg *ifal;
381 struct nlattr *tb[IFAL_MAX+1];
382 struct in6_addr *pfx;
383 u32 label;
384 int err = 0;
385
386 err = nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb, IFAL_MAX,
387 ifal_policy, extack);
388 if (err < 0)
389 return err;
390
391 ifal = nlmsg_data(nlh);
392
393 if (ifal->ifal_family != AF_INET6 ||
394 ifal->ifal_prefixlen > 128)
395 return -EINVAL;
396
397 if (!tb[IFAL_ADDRESS])
398 return -EINVAL;
399 pfx = nla_data(tb[IFAL_ADDRESS]);
400
401 if (!tb[IFAL_LABEL])
402 return -EINVAL;
403 label = nla_get_u32(tb[IFAL_LABEL]);
404 if (label == IPV6_ADDR_LABEL_DEFAULT)
405 return -EINVAL;
406
407 switch (nlh->nlmsg_type) {
408 case RTM_NEWADDRLABEL:
409 if (ifal->ifal_index &&
410 !addrlbl_ifindex_exists(net, ifal->ifal_index))
411 return -EINVAL;
412
413 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
414 ifal->ifal_index, label,
415 nlh->nlmsg_flags & NLM_F_REPLACE);
416 break;
417 case RTM_DELADDRLABEL:
418 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
419 ifal->ifal_index);
420 break;
421 default:
422 err = -EOPNOTSUPP;
423 }
424 return err;
425}
426
427static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
428 int prefixlen, int ifindex, u32 lseq)
429{
430 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
431 ifal->ifal_family = AF_INET6;
432 ifal->ifal_prefixlen = prefixlen;
433 ifal->ifal_flags = 0;
434 ifal->ifal_index = ifindex;
435 ifal->ifal_seq = lseq;
436};
437
438static int ip6addrlbl_fill(struct sk_buff *skb,
439 struct ip6addrlbl_entry *p,
440 u32 lseq,
441 u32 portid, u32 seq, int event,
442 unsigned int flags)
443{
444 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
445 sizeof(struct ifaddrlblmsg), flags);
446 if (!nlh)
447 return -EMSGSIZE;
448
449 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
450
451 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
452 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
453 nlmsg_cancel(skb, nlh);
454 return -EMSGSIZE;
455 }
456
457 nlmsg_end(skb, nlh);
458 return 0;
459}
460
461static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
462 struct netlink_ext_ack *extack)
463{
464 struct ifaddrlblmsg *ifal;
465
466 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
467 NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
468 return -EINVAL;
469 }
470
471 ifal = nlmsg_data(nlh);
472 if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
473 ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
474 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
475 return -EINVAL;
476 }
477
478 if (nlmsg_attrlen(nlh, sizeof(*ifal))) {
479 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header for address label dump request");
480 return -EINVAL;
481 }
482
483 return 0;
484}
485
486static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
487{
488 const struct nlmsghdr *nlh = cb->nlh;
489 struct net *net = sock_net(skb->sk);
490 struct ip6addrlbl_entry *p;
491 int idx = 0, s_idx = cb->args[0];
492 int err;
493
494 if (cb->strict_check) {
495 err = ip6addrlbl_valid_dump_req(nlh, cb->extack);
496 if (err < 0)
497 return err;
498 }
499
500 rcu_read_lock();
501 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
502 if (idx >= s_idx) {
503 err = ip6addrlbl_fill(skb, p,
504 net->ipv6.ip6addrlbl_table.seq,
505 NETLINK_CB(cb->skb).portid,
506 nlh->nlmsg_seq,
507 RTM_NEWADDRLABEL,
508 NLM_F_MULTI);
509 if (err < 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) /* IFAL_ADDRESS */
523 + nla_total_size(4); /* IFAL_LABEL */
524}
525
526static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
527 const struct nlmsghdr *nlh,
528 struct nlattr **tb,
529 struct netlink_ext_ack *extack)
530{
531 struct ifaddrlblmsg *ifal;
532 int i, err;
533
534 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
535 NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
536 return -EINVAL;
537 }
538
539 if (!netlink_strict_get_check(skb))
540 return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
541 IFAL_MAX, ifal_policy, extack);
542
543 ifal = nlmsg_data(nlh);
544 if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
545 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
546 return -EINVAL;
547 }
548
549 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifal), tb, IFAL_MAX,
550 ifal_policy, extack);
551 if (err)
552 return err;
553
554 for (i = 0; i <= IFAL_MAX; i++) {
555 if (!tb[i])
556 continue;
557
558 switch (i) {
559 case IFAL_ADDRESS:
560 break;
561 default:
562 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in addrlabel get request");
563 return -EINVAL;
564 }
565 }
566
567 return 0;
568}
569
570static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
571 struct netlink_ext_ack *extack)
572{
573 struct net *net = sock_net(in_skb->sk);
574 struct ifaddrlblmsg *ifal;
575 struct nlattr *tb[IFAL_MAX+1];
576 struct in6_addr *addr;
577 u32 lseq;
578 int err = 0;
579 struct ip6addrlbl_entry *p;
580 struct sk_buff *skb;
581
582 err = ip6addrlbl_valid_get_req(in_skb, nlh, tb, extack);
583 if (err < 0)
584 return err;
585
586 ifal = nlmsg_data(nlh);
587
588 if (ifal->ifal_family != AF_INET6 ||
589 ifal->ifal_prefixlen != 128)
590 return -EINVAL;
591
592 if (ifal->ifal_index &&
593 !addrlbl_ifindex_exists(net, ifal->ifal_index))
594 return -EINVAL;
595
596 if (!tb[IFAL_ADDRESS])
597 return -EINVAL;
598 addr = nla_data(tb[IFAL_ADDRESS]);
599
600 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
601 if (!skb)
602 return -ENOBUFS;
603
604 err = -ESRCH;
605
606 rcu_read_lock();
607 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
608 lseq = net->ipv6.ip6addrlbl_table.seq;
609 if (p)
610 err = ip6addrlbl_fill(skb, p, lseq,
611 NETLINK_CB(in_skb).portid,
612 nlh->nlmsg_seq,
613 RTM_NEWADDRLABEL, 0);
614 rcu_read_unlock();
615
616 if (err < 0) {
617 WARN_ON(err == -EMSGSIZE);
618 kfree_skb(skb);
619 } else {
620 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
621 }
622 return err;
623}
624
625int __init ipv6_addr_label_rtnl_register(void)
626{
627 int ret;
628
629 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDRLABEL,
630 ip6addrlbl_newdel,
631 NULL, RTNL_FLAG_DOIT_UNLOCKED);
632 if (ret < 0)
633 return ret;
634 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDRLABEL,
635 ip6addrlbl_newdel,
636 NULL, RTNL_FLAG_DOIT_UNLOCKED);
637 if (ret < 0)
638 return ret;
639 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDRLABEL,
640 ip6addrlbl_get,
641 ip6addrlbl_dump, RTNL_FLAG_DOIT_UNLOCKED);
642 return ret;
643}