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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#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 return read_pnet(&lbl->lbl_net);
56}
57
58/*
59 * Default policy table (RFC6724 + extensions)
60 *
61 * prefix addr_type label
62 * -------------------------------------------------------------------------
63 * ::1/128 LOOPBACK 0
64 * ::/0 N/A 1
65 * 2002::/16 N/A 2
66 * ::/96 COMPATv4 3
67 * ::ffff:0:0/96 V4MAPPED 4
68 * fc00::/7 N/A 5 ULA (RFC 4193)
69 * 2001::/32 N/A 6 Teredo (RFC 4380)
70 * 2001:10::/28 N/A 7 ORCHID (RFC 4843)
71 * fec0::/10 N/A 11 Site-local
72 * (deprecated by RFC3879)
73 * 3ffe::/16 N/A 12 6bone
74 *
75 * Note: 0xffffffff is used if we do not have any policies.
76 * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724.
77 */
78
79#define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL
80
81static const __net_initconst struct ip6addrlbl_init_table
82{
83 const struct in6_addr *prefix;
84 int prefixlen;
85 u32 label;
86} ip6addrlbl_init_table[] = {
87 { /* ::/0 */
88 .prefix = &in6addr_any,
89 .label = 1,
90 }, { /* fc00::/7 */
91 .prefix = &(struct in6_addr){ { { 0xfc } } } ,
92 .prefixlen = 7,
93 .label = 5,
94 }, { /* fec0::/10 */
95 .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } },
96 .prefixlen = 10,
97 .label = 11,
98 }, { /* 2002::/16 */
99 .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } },
100 .prefixlen = 16,
101 .label = 2,
102 }, { /* 3ffe::/16 */
103 .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } },
104 .prefixlen = 16,
105 .label = 12,
106 }, { /* 2001::/32 */
107 .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } },
108 .prefixlen = 32,
109 .label = 6,
110 }, { /* 2001:10::/28 */
111 .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } },
112 .prefixlen = 28,
113 .label = 7,
114 }, { /* ::ffff:0:0 */
115 .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } },
116 .prefixlen = 96,
117 .label = 4,
118 }, { /* ::/96 */
119 .prefix = &in6addr_any,
120 .prefixlen = 96,
121 .label = 3,
122 }, { /* ::1/128 */
123 .prefix = &in6addr_loopback,
124 .prefixlen = 128,
125 .label = 0,
126 }
127};
128
129/* Object management */
130static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
131{
132#ifdef CONFIG_NET_NS
133 release_net(p->lbl_net);
134#endif
135 kfree(p);
136}
137
138static void ip6addrlbl_free_rcu(struct rcu_head *h)
139{
140 ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu));
141}
142
143static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p)
144{
145 return atomic_inc_not_zero(&p->refcnt);
146}
147
148static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
149{
150 if (atomic_dec_and_test(&p->refcnt))
151 call_rcu(&p->rcu, ip6addrlbl_free_rcu);
152}
153
154/* Find label */
155static bool __ip6addrlbl_match(struct net *net,
156 const struct ip6addrlbl_entry *p,
157 const struct in6_addr *addr,
158 int addrtype, int ifindex)
159{
160 if (!net_eq(ip6addrlbl_net(p), net))
161 return false;
162 if (p->ifindex && p->ifindex != ifindex)
163 return false;
164 if (p->addrtype && p->addrtype != addrtype)
165 return false;
166 if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen))
167 return false;
168 return true;
169}
170
171static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
172 const struct in6_addr *addr,
173 int type, int ifindex)
174{
175 struct ip6addrlbl_entry *p;
176 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
177 if (__ip6addrlbl_match(net, p, addr, type, ifindex))
178 return p;
179 }
180 return NULL;
181}
182
183u32 ipv6_addr_label(struct net *net,
184 const struct in6_addr *addr, int type, int ifindex)
185{
186 u32 label;
187 struct ip6addrlbl_entry *p;
188
189 type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
190
191 rcu_read_lock();
192 p = __ipv6_addr_label(net, addr, type, ifindex);
193 label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
194 rcu_read_unlock();
195
196 ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n",
197 __func__, addr, type, ifindex, label);
198
199 return label;
200}
201
202/* allocate one entry */
203static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net,
204 const struct in6_addr *prefix,
205 int prefixlen, int ifindex,
206 u32 label)
207{
208 struct ip6addrlbl_entry *newp;
209 int addrtype;
210
211 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n",
212 __func__, prefix, prefixlen, ifindex, (unsigned int)label);
213
214 addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK);
215
216 switch (addrtype) {
217 case IPV6_ADDR_MAPPED:
218 if (prefixlen > 96)
219 return ERR_PTR(-EINVAL);
220 if (prefixlen < 96)
221 addrtype = 0;
222 break;
223 case IPV6_ADDR_COMPATv4:
224 if (prefixlen != 96)
225 addrtype = 0;
226 break;
227 case IPV6_ADDR_LOOPBACK:
228 if (prefixlen != 128)
229 addrtype = 0;
230 break;
231 }
232
233 newp = kmalloc(sizeof(*newp), GFP_KERNEL);
234 if (!newp)
235 return ERR_PTR(-ENOMEM);
236
237 ipv6_addr_prefix(&newp->prefix, prefix, prefixlen);
238 newp->prefixlen = prefixlen;
239 newp->ifindex = ifindex;
240 newp->addrtype = addrtype;
241 newp->label = label;
242 INIT_HLIST_NODE(&newp->list);
243#ifdef CONFIG_NET_NS
244 newp->lbl_net = hold_net(net);
245#endif
246 atomic_set(&newp->refcnt, 1);
247 return newp;
248}
249
250/* add a label */
251static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
252{
253 struct hlist_node *n;
254 struct ip6addrlbl_entry *last = NULL, *p = NULL;
255 int ret = 0;
256
257 ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp,
258 replace);
259
260 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
261 if (p->prefixlen == newp->prefixlen &&
262 net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
263 p->ifindex == newp->ifindex &&
264 ipv6_addr_equal(&p->prefix, &newp->prefix)) {
265 if (!replace) {
266 ret = -EEXIST;
267 goto out;
268 }
269 hlist_replace_rcu(&p->list, &newp->list);
270 ip6addrlbl_put(p);
271 goto out;
272 } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) ||
273 (p->prefixlen < newp->prefixlen)) {
274 hlist_add_before_rcu(&newp->list, &p->list);
275 goto out;
276 }
277 last = p;
278 }
279 if (last)
280 hlist_add_after_rcu(&last->list, &newp->list);
281 else
282 hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
283out:
284 if (!ret)
285 ip6addrlbl_table.seq++;
286 return ret;
287}
288
289/* add a label */
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=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
298 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
299 replace);
300
301 newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
302 if (IS_ERR(newp))
303 return PTR_ERR(newp);
304 spin_lock(&ip6addrlbl_table.lock);
305 ret = __ip6addrlbl_add(newp, replace);
306 spin_unlock(&ip6addrlbl_table.lock);
307 if (ret)
308 ip6addrlbl_free(newp);
309 return ret;
310}
311
312/* remove a label */
313static int __ip6addrlbl_del(struct net *net,
314 const struct in6_addr *prefix, int prefixlen,
315 int ifindex)
316{
317 struct ip6addrlbl_entry *p = NULL;
318 struct hlist_node *n;
319 int ret = -ESRCH;
320
321 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
322 __func__, prefix, prefixlen, ifindex);
323
324 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
325 if (p->prefixlen == prefixlen &&
326 net_eq(ip6addrlbl_net(p), net) &&
327 p->ifindex == ifindex &&
328 ipv6_addr_equal(&p->prefix, prefix)) {
329 hlist_del_rcu(&p->list);
330 ip6addrlbl_put(p);
331 ret = 0;
332 break;
333 }
334 }
335 return ret;
336}
337
338static int ip6addrlbl_del(struct net *net,
339 const struct in6_addr *prefix, int prefixlen,
340 int ifindex)
341{
342 struct in6_addr prefix_buf;
343 int ret;
344
345 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
346 __func__, prefix, prefixlen, ifindex);
347
348 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
349 spin_lock(&ip6addrlbl_table.lock);
350 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
351 spin_unlock(&ip6addrlbl_table.lock);
352 return ret;
353}
354
355/* add default label */
356static int __net_init ip6addrlbl_net_init(struct net *net)
357{
358 int err = 0;
359 int i;
360
361 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
362
363 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
364 int ret = ip6addrlbl_add(net,
365 ip6addrlbl_init_table[i].prefix,
366 ip6addrlbl_init_table[i].prefixlen,
367 0,
368 ip6addrlbl_init_table[i].label, 0);
369 /* XXX: should we free all rules when we catch an error? */
370 if (ret && (!err || err != -ENOMEM))
371 err = ret;
372 }
373 return err;
374}
375
376static void __net_exit ip6addrlbl_net_exit(struct net *net)
377{
378 struct ip6addrlbl_entry *p = NULL;
379 struct hlist_node *n;
380
381 /* Remove all labels belonging to the exiting net */
382 spin_lock(&ip6addrlbl_table.lock);
383 hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
384 if (net_eq(ip6addrlbl_net(p), net)) {
385 hlist_del_rcu(&p->list);
386 ip6addrlbl_put(p);
387 }
388 }
389 spin_unlock(&ip6addrlbl_table.lock);
390}
391
392static struct pernet_operations ipv6_addr_label_ops = {
393 .init = ip6addrlbl_net_init,
394 .exit = ip6addrlbl_net_exit,
395};
396
397int __init ipv6_addr_label_init(void)
398{
399 spin_lock_init(&ip6addrlbl_table.lock);
400
401 return register_pernet_subsys(&ipv6_addr_label_ops);
402}
403
404void ipv6_addr_label_cleanup(void)
405{
406 unregister_pernet_subsys(&ipv6_addr_label_ops);
407}
408
409static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
410 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
411 [IFAL_LABEL] = { .len = sizeof(u32), },
412};
413
414static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh)
415{
416 struct net *net = sock_net(skb->sk);
417 struct ifaddrlblmsg *ifal;
418 struct nlattr *tb[IFAL_MAX+1];
419 struct in6_addr *pfx;
420 u32 label;
421 int err = 0;
422
423 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
424 if (err < 0)
425 return err;
426
427 ifal = nlmsg_data(nlh);
428
429 if (ifal->ifal_family != AF_INET6 ||
430 ifal->ifal_prefixlen > 128)
431 return -EINVAL;
432
433 if (!tb[IFAL_ADDRESS])
434 return -EINVAL;
435 pfx = nla_data(tb[IFAL_ADDRESS]);
436
437 if (!tb[IFAL_LABEL])
438 return -EINVAL;
439 label = nla_get_u32(tb[IFAL_LABEL]);
440 if (label == IPV6_ADDR_LABEL_DEFAULT)
441 return -EINVAL;
442
443 switch (nlh->nlmsg_type) {
444 case RTM_NEWADDRLABEL:
445 if (ifal->ifal_index &&
446 !__dev_get_by_index(net, ifal->ifal_index))
447 return -EINVAL;
448
449 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
450 ifal->ifal_index, label,
451 nlh->nlmsg_flags & NLM_F_REPLACE);
452 break;
453 case RTM_DELADDRLABEL:
454 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
455 ifal->ifal_index);
456 break;
457 default:
458 err = -EOPNOTSUPP;
459 }
460 return err;
461}
462
463static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
464 int prefixlen, int ifindex, u32 lseq)
465{
466 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
467 ifal->ifal_family = AF_INET6;
468 ifal->ifal_prefixlen = prefixlen;
469 ifal->ifal_flags = 0;
470 ifal->ifal_index = ifindex;
471 ifal->ifal_seq = lseq;
472};
473
474static int ip6addrlbl_fill(struct sk_buff *skb,
475 struct ip6addrlbl_entry *p,
476 u32 lseq,
477 u32 portid, u32 seq, int event,
478 unsigned int flags)
479{
480 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
481 sizeof(struct ifaddrlblmsg), flags);
482 if (!nlh)
483 return -EMSGSIZE;
484
485 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
486
487 if (nla_put(skb, IFAL_ADDRESS, 16, &p->prefix) < 0 ||
488 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
489 nlmsg_cancel(skb, nlh);
490 return -EMSGSIZE;
491 }
492
493 return nlmsg_end(skb, nlh);
494}
495
496static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
497{
498 struct net *net = sock_net(skb->sk);
499 struct ip6addrlbl_entry *p;
500 int idx = 0, s_idx = cb->args[0];
501 int err;
502
503 rcu_read_lock();
504 hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
505 if (idx >= s_idx &&
506 net_eq(ip6addrlbl_net(p), net)) {
507 err = ip6addrlbl_fill(skb, p,
508 ip6addrlbl_table.seq,
509 NETLINK_CB(cb->skb).portid,
510 cb->nlh->nlmsg_seq,
511 RTM_NEWADDRLABEL,
512 NLM_F_MULTI);
513 if (err <= 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) /* IFAL_ADDRESS */
527 + nla_total_size(4); /* IFAL_LABEL */
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 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
572 if (!skb) {
573 ip6addrlbl_put(p);
574 return -ENOBUFS;
575 }
576
577 err = ip6addrlbl_fill(skb, p, lseq,
578 NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
579 RTM_NEWADDRLABEL, 0);
580
581 ip6addrlbl_put(p);
582
583 if (err < 0) {
584 WARN_ON(err == -EMSGSIZE);
585 kfree_skb(skb);
586 goto out;
587 }
588
589 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
590out:
591 return err;
592}
593
594void __init ipv6_addr_label_rtnl_register(void)
595{
596 __rtnl_register(PF_INET6, RTM_NEWADDRLABEL, ip6addrlbl_newdel,
597 NULL, NULL);
598 __rtnl_register(PF_INET6, RTM_DELADDRLABEL, ip6addrlbl_newdel,
599 NULL, NULL);
600 __rtnl_register(PF_INET6, RTM_GETADDRLABEL, ip6addrlbl_get,
601 ip6addrlbl_dump, NULL);
602}
603
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 WRITE_ONCE(net->ipv6.ip6addrlbl_table.seq,
238 net->ipv6.ip6addrlbl_table.seq + 1);
239 return ret;
240}
241
242/* add a label */
243static int ip6addrlbl_add(struct net *net,
244 const struct in6_addr *prefix, int prefixlen,
245 int ifindex, u32 label, int replace)
246{
247 struct ip6addrlbl_entry *newp;
248 int ret = 0;
249
250 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n",
251 __func__, prefix, prefixlen, ifindex, (unsigned int)label,
252 replace);
253
254 newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
255 if (IS_ERR(newp))
256 return PTR_ERR(newp);
257 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
258 ret = __ip6addrlbl_add(net, newp, replace);
259 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
260 if (ret)
261 kfree(newp);
262 return ret;
263}
264
265/* remove a label */
266static int __ip6addrlbl_del(struct net *net,
267 const struct in6_addr *prefix, int prefixlen,
268 int ifindex)
269{
270 struct ip6addrlbl_entry *p = NULL;
271 struct hlist_node *n;
272 int ret = -ESRCH;
273
274 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
275 __func__, prefix, prefixlen, ifindex);
276
277 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
278 if (p->prefixlen == prefixlen &&
279 p->ifindex == ifindex &&
280 ipv6_addr_equal(&p->prefix, prefix)) {
281 hlist_del_rcu(&p->list);
282 kfree_rcu(p, rcu);
283 ret = 0;
284 break;
285 }
286 }
287 return ret;
288}
289
290static int ip6addrlbl_del(struct net *net,
291 const struct in6_addr *prefix, int prefixlen,
292 int ifindex)
293{
294 struct in6_addr prefix_buf;
295 int ret;
296
297 ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
298 __func__, prefix, prefixlen, ifindex);
299
300 ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
301 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
302 ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
303 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
304 return ret;
305}
306
307/* add default label */
308static int __net_init ip6addrlbl_net_init(struct net *net)
309{
310 struct ip6addrlbl_entry *p = NULL;
311 struct hlist_node *n;
312 int err;
313 int i;
314
315 ADDRLABEL(KERN_DEBUG "%s\n", __func__);
316
317 spin_lock_init(&net->ipv6.ip6addrlbl_table.lock);
318 INIT_HLIST_HEAD(&net->ipv6.ip6addrlbl_table.head);
319
320 for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
321 err = ip6addrlbl_add(net,
322 ip6addrlbl_init_table[i].prefix,
323 ip6addrlbl_init_table[i].prefixlen,
324 0,
325 ip6addrlbl_init_table[i].label, 0);
326 if (err)
327 goto err_ip6addrlbl_add;
328 }
329 return 0;
330
331err_ip6addrlbl_add:
332 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
333 hlist_del_rcu(&p->list);
334 kfree_rcu(p, rcu);
335 }
336 return err;
337}
338
339static void __net_exit ip6addrlbl_net_exit(struct net *net)
340{
341 struct ip6addrlbl_entry *p = NULL;
342 struct hlist_node *n;
343
344 /* Remove all labels belonging to the exiting net */
345 spin_lock(&net->ipv6.ip6addrlbl_table.lock);
346 hlist_for_each_entry_safe(p, n, &net->ipv6.ip6addrlbl_table.head, list) {
347 hlist_del_rcu(&p->list);
348 kfree_rcu(p, rcu);
349 }
350 spin_unlock(&net->ipv6.ip6addrlbl_table.lock);
351}
352
353static struct pernet_operations ipv6_addr_label_ops = {
354 .init = ip6addrlbl_net_init,
355 .exit = ip6addrlbl_net_exit,
356};
357
358int __init ipv6_addr_label_init(void)
359{
360 return register_pernet_subsys(&ipv6_addr_label_ops);
361}
362
363void ipv6_addr_label_cleanup(void)
364{
365 unregister_pernet_subsys(&ipv6_addr_label_ops);
366}
367
368static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
369 [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), },
370 [IFAL_LABEL] = { .len = sizeof(u32), },
371};
372
373static bool addrlbl_ifindex_exists(struct net *net, int ifindex)
374{
375
376 struct net_device *dev;
377
378 rcu_read_lock();
379 dev = dev_get_by_index_rcu(net, ifindex);
380 rcu_read_unlock();
381
382 return dev != NULL;
383}
384
385static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
386 struct netlink_ext_ack *extack)
387{
388 struct net *net = sock_net(skb->sk);
389 struct ifaddrlblmsg *ifal;
390 struct nlattr *tb[IFAL_MAX+1];
391 struct in6_addr *pfx;
392 u32 label;
393 int err = 0;
394
395 err = nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb, IFAL_MAX,
396 ifal_policy, extack);
397 if (err < 0)
398 return err;
399
400 ifal = nlmsg_data(nlh);
401
402 if (ifal->ifal_family != AF_INET6 ||
403 ifal->ifal_prefixlen > 128)
404 return -EINVAL;
405
406 if (!tb[IFAL_ADDRESS])
407 return -EINVAL;
408 pfx = nla_data(tb[IFAL_ADDRESS]);
409
410 if (!tb[IFAL_LABEL])
411 return -EINVAL;
412 label = nla_get_u32(tb[IFAL_LABEL]);
413 if (label == IPV6_ADDR_LABEL_DEFAULT)
414 return -EINVAL;
415
416 switch (nlh->nlmsg_type) {
417 case RTM_NEWADDRLABEL:
418 if (ifal->ifal_index &&
419 !addrlbl_ifindex_exists(net, ifal->ifal_index))
420 return -EINVAL;
421
422 err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
423 ifal->ifal_index, label,
424 nlh->nlmsg_flags & NLM_F_REPLACE);
425 break;
426 case RTM_DELADDRLABEL:
427 err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
428 ifal->ifal_index);
429 break;
430 default:
431 err = -EOPNOTSUPP;
432 }
433 return err;
434}
435
436static void ip6addrlbl_putmsg(struct nlmsghdr *nlh,
437 int prefixlen, int ifindex, u32 lseq)
438{
439 struct ifaddrlblmsg *ifal = nlmsg_data(nlh);
440 ifal->ifal_family = AF_INET6;
441 ifal->__ifal_reserved = 0;
442 ifal->ifal_prefixlen = prefixlen;
443 ifal->ifal_flags = 0;
444 ifal->ifal_index = ifindex;
445 ifal->ifal_seq = lseq;
446};
447
448static int ip6addrlbl_fill(struct sk_buff *skb,
449 const struct ip6addrlbl_entry *p,
450 u32 lseq,
451 u32 portid, u32 seq, int event,
452 unsigned int flags)
453{
454 struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event,
455 sizeof(struct ifaddrlblmsg), flags);
456 if (!nlh)
457 return -EMSGSIZE;
458
459 ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq);
460
461 if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 ||
462 nla_put_u32(skb, IFAL_LABEL, p->label) < 0) {
463 nlmsg_cancel(skb, nlh);
464 return -EMSGSIZE;
465 }
466
467 nlmsg_end(skb, nlh);
468 return 0;
469}
470
471static int ip6addrlbl_valid_dump_req(const struct nlmsghdr *nlh,
472 struct netlink_ext_ack *extack)
473{
474 struct ifaddrlblmsg *ifal;
475
476 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
477 NL_SET_ERR_MSG_MOD(extack, "Invalid header for address label dump request");
478 return -EINVAL;
479 }
480
481 ifal = nlmsg_data(nlh);
482 if (ifal->__ifal_reserved || ifal->ifal_prefixlen ||
483 ifal->ifal_flags || ifal->ifal_index || ifal->ifal_seq) {
484 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address label dump request");
485 return -EINVAL;
486 }
487
488 if (nlmsg_attrlen(nlh, sizeof(*ifal))) {
489 NL_SET_ERR_MSG_MOD(extack, "Invalid data after header for address label dump request");
490 return -EINVAL;
491 }
492
493 return 0;
494}
495
496static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
497{
498 const struct nlmsghdr *nlh = cb->nlh;
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 = 0;
503 u32 lseq;
504
505 if (cb->strict_check) {
506 err = ip6addrlbl_valid_dump_req(nlh, cb->extack);
507 if (err < 0)
508 return err;
509 }
510
511 rcu_read_lock();
512 lseq = READ_ONCE(net->ipv6.ip6addrlbl_table.seq);
513 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
514 if (idx >= s_idx) {
515 err = ip6addrlbl_fill(skb, p,
516 lseq,
517 NETLINK_CB(cb->skb).portid,
518 nlh->nlmsg_seq,
519 RTM_NEWADDRLABEL,
520 NLM_F_MULTI);
521 if (err < 0)
522 break;
523 }
524 idx++;
525 }
526 rcu_read_unlock();
527 cb->args[0] = idx;
528 return err;
529}
530
531static inline int ip6addrlbl_msgsize(void)
532{
533 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
534 + nla_total_size(16) /* IFAL_ADDRESS */
535 + nla_total_size(4); /* IFAL_LABEL */
536}
537
538static int ip6addrlbl_valid_get_req(struct sk_buff *skb,
539 const struct nlmsghdr *nlh,
540 struct nlattr **tb,
541 struct netlink_ext_ack *extack)
542{
543 struct ifaddrlblmsg *ifal;
544 int i, err;
545
546 if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifal))) {
547 NL_SET_ERR_MSG_MOD(extack, "Invalid header for addrlabel get request");
548 return -EINVAL;
549 }
550
551 if (!netlink_strict_get_check(skb))
552 return nlmsg_parse_deprecated(nlh, sizeof(*ifal), tb,
553 IFAL_MAX, ifal_policy, extack);
554
555 ifal = nlmsg_data(nlh);
556 if (ifal->__ifal_reserved || ifal->ifal_flags || ifal->ifal_seq) {
557 NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for addrlabel get request");
558 return -EINVAL;
559 }
560
561 err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifal), tb, IFAL_MAX,
562 ifal_policy, extack);
563 if (err)
564 return err;
565
566 for (i = 0; i <= IFAL_MAX; i++) {
567 if (!tb[i])
568 continue;
569
570 switch (i) {
571 case IFAL_ADDRESS:
572 break;
573 default:
574 NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in addrlabel get request");
575 return -EINVAL;
576 }
577 }
578
579 return 0;
580}
581
582static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
583 struct netlink_ext_ack *extack)
584{
585 struct net *net = sock_net(in_skb->sk);
586 struct ifaddrlblmsg *ifal;
587 struct nlattr *tb[IFAL_MAX+1];
588 struct in6_addr *addr;
589 u32 lseq;
590 int err = 0;
591 struct ip6addrlbl_entry *p;
592 struct sk_buff *skb;
593
594 err = ip6addrlbl_valid_get_req(in_skb, nlh, tb, extack);
595 if (err < 0)
596 return err;
597
598 ifal = nlmsg_data(nlh);
599
600 if (ifal->ifal_family != AF_INET6 ||
601 ifal->ifal_prefixlen != 128)
602 return -EINVAL;
603
604 if (ifal->ifal_index &&
605 !addrlbl_ifindex_exists(net, ifal->ifal_index))
606 return -EINVAL;
607
608 if (!tb[IFAL_ADDRESS])
609 return -EINVAL;
610 addr = nla_data(tb[IFAL_ADDRESS]);
611
612 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
613 if (!skb)
614 return -ENOBUFS;
615
616 err = -ESRCH;
617
618 rcu_read_lock();
619 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
620 lseq = READ_ONCE(net->ipv6.ip6addrlbl_table.seq);
621 if (p)
622 err = ip6addrlbl_fill(skb, p, lseq,
623 NETLINK_CB(in_skb).portid,
624 nlh->nlmsg_seq,
625 RTM_NEWADDRLABEL, 0);
626 rcu_read_unlock();
627
628 if (err < 0) {
629 WARN_ON(err == -EMSGSIZE);
630 kfree_skb(skb);
631 } else {
632 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
633 }
634 return err;
635}
636
637static const struct rtnl_msg_handler ipv6_adddr_label_rtnl_msg_handlers[] __initconst_or_module = {
638 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_NEWADDRLABEL,
639 .doit = ip6addrlbl_newdel, .flags = RTNL_FLAG_DOIT_UNLOCKED},
640 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_DELADDRLABEL,
641 .doit = ip6addrlbl_newdel, .flags = RTNL_FLAG_DOIT_UNLOCKED},
642 {.owner = THIS_MODULE, .protocol = PF_INET6, .msgtype = RTM_GETADDRLABEL,
643 .doit = ip6addrlbl_get, .dumpit = ip6addrlbl_dump,
644 .flags = RTNL_FLAG_DOIT_UNLOCKED | RTNL_FLAG_DUMP_UNLOCKED},
645};
646
647int __init ipv6_addr_label_rtnl_register(void)
648{
649 return rtnl_register_many(ipv6_adddr_label_rtnl_msg_handlers);
650}