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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 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(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy,
387 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_dump(struct sk_buff *skb, struct netlink_callback *cb)
462{
463 struct net *net = sock_net(skb->sk);
464 struct ip6addrlbl_entry *p;
465 int idx = 0, s_idx = cb->args[0];
466 int err;
467
468 rcu_read_lock();
469 hlist_for_each_entry_rcu(p, &net->ipv6.ip6addrlbl_table.head, list) {
470 if (idx >= s_idx) {
471 err = ip6addrlbl_fill(skb, p,
472 net->ipv6.ip6addrlbl_table.seq,
473 NETLINK_CB(cb->skb).portid,
474 cb->nlh->nlmsg_seq,
475 RTM_NEWADDRLABEL,
476 NLM_F_MULTI);
477 if (err < 0)
478 break;
479 }
480 idx++;
481 }
482 rcu_read_unlock();
483 cb->args[0] = idx;
484 return skb->len;
485}
486
487static inline int ip6addrlbl_msgsize(void)
488{
489 return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg))
490 + nla_total_size(16) /* IFAL_ADDRESS */
491 + nla_total_size(4); /* IFAL_LABEL */
492}
493
494static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh,
495 struct netlink_ext_ack *extack)
496{
497 struct net *net = sock_net(in_skb->sk);
498 struct ifaddrlblmsg *ifal;
499 struct nlattr *tb[IFAL_MAX+1];
500 struct in6_addr *addr;
501 u32 lseq;
502 int err = 0;
503 struct ip6addrlbl_entry *p;
504 struct sk_buff *skb;
505
506 err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy,
507 extack);
508 if (err < 0)
509 return err;
510
511 ifal = nlmsg_data(nlh);
512
513 if (ifal->ifal_family != AF_INET6 ||
514 ifal->ifal_prefixlen != 128)
515 return -EINVAL;
516
517 if (ifal->ifal_index &&
518 !addrlbl_ifindex_exists(net, ifal->ifal_index))
519 return -EINVAL;
520
521 if (!tb[IFAL_ADDRESS])
522 return -EINVAL;
523 addr = nla_data(tb[IFAL_ADDRESS]);
524
525 skb = nlmsg_new(ip6addrlbl_msgsize(), GFP_KERNEL);
526 if (!skb)
527 return -ENOBUFS;
528
529 err = -ESRCH;
530
531 rcu_read_lock();
532 p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
533 lseq = net->ipv6.ip6addrlbl_table.seq;
534 if (p)
535 err = ip6addrlbl_fill(skb, p, lseq,
536 NETLINK_CB(in_skb).portid,
537 nlh->nlmsg_seq,
538 RTM_NEWADDRLABEL, 0);
539 rcu_read_unlock();
540
541 if (err < 0) {
542 WARN_ON(err == -EMSGSIZE);
543 kfree_skb(skb);
544 } else {
545 err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
546 }
547 return err;
548}
549
550int __init ipv6_addr_label_rtnl_register(void)
551{
552 int ret;
553
554 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDRLABEL,
555 ip6addrlbl_newdel,
556 NULL, RTNL_FLAG_DOIT_UNLOCKED);
557 if (ret < 0)
558 return ret;
559 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDRLABEL,
560 ip6addrlbl_newdel,
561 NULL, RTNL_FLAG_DOIT_UNLOCKED);
562 if (ret < 0)
563 return ret;
564 ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDRLABEL,
565 ip6addrlbl_get,
566 ip6addrlbl_dump, RTNL_FLAG_DOIT_UNLOCKED);
567 return ret;
568}