1
2#include <linux/jhash.h>
3#include <linux/netfilter.h>
4#include <linux/rcupdate.h>
5#include <linux/rhashtable.h>
6#include <linux/vmalloc.h>
7#include <net/genetlink.h>
8#include <net/ila.h>
9#include <net/netns/generic.h>
10#include <uapi/linux/genetlink.h>
11#include "ila.h"
12
13struct ila_xlat_params {
14 struct ila_params ip;
15 int ifindex;
16};
17
18struct ila_map {
19 struct ila_xlat_params xp;
20 struct rhash_head node;
21 struct ila_map __rcu *next;
22 struct rcu_head rcu;
23};
24
25#define MAX_LOCKS 1024
26#define LOCKS_PER_CPU 10
27
28static int alloc_ila_locks(struct ila_net *ilan)
29{
30 return alloc_bucket_spinlocks(&ilan->xlat.locks, &ilan->xlat.locks_mask,
31 MAX_LOCKS, LOCKS_PER_CPU,
32 GFP_KERNEL);
33}
34
35static u32 hashrnd __read_mostly;
36static __always_inline void __ila_hash_secret_init(void)
37{
38 net_get_random_once(&hashrnd, sizeof(hashrnd));
39}
40
41static inline u32 ila_locator_hash(struct ila_locator loc)
42{
43 u32 *v = (u32 *)loc.v32;
44
45 __ila_hash_secret_init();
46 return jhash_2words(v[0], v[1], hashrnd);
47}
48
49static inline spinlock_t *ila_get_lock(struct ila_net *ilan,
50 struct ila_locator loc)
51{
52 return &ilan->xlat.locks[ila_locator_hash(loc) & ilan->xlat.locks_mask];
53}
54
55static inline int ila_cmp_wildcards(struct ila_map *ila,
56 struct ila_addr *iaddr, int ifindex)
57{
58 return (ila->xp.ifindex && ila->xp.ifindex != ifindex);
59}
60
61static inline int ila_cmp_params(struct ila_map *ila,
62 struct ila_xlat_params *xp)
63{
64 return (ila->xp.ifindex != xp->ifindex);
65}
66
67static int ila_cmpfn(struct rhashtable_compare_arg *arg,
68 const void *obj)
69{
70 const struct ila_map *ila = obj;
71
72 return (ila->xp.ip.locator_match.v64 != *(__be64 *)arg->key);
73}
74
75static inline int ila_order(struct ila_map *ila)
76{
77 int score = 0;
78
79 if (ila->xp.ifindex)
80 score += 1 << 1;
81
82 return score;
83}
84
85static const struct rhashtable_params rht_params = {
86 .nelem_hint = 1024,
87 .head_offset = offsetof(struct ila_map, node),
88 .key_offset = offsetof(struct ila_map, xp.ip.locator_match),
89 .key_len = sizeof(u64),
90 .max_size = 1048576,
91 .min_size = 256,
92 .automatic_shrinking = true,
93 .obj_cmpfn = ila_cmpfn,
94};
95
96static int parse_nl_config(struct genl_info *info,
97 struct ila_xlat_params *xp)
98{
99 memset(xp, 0, sizeof(*xp));
100
101 if (info->attrs[ILA_ATTR_LOCATOR])
102 xp->ip.locator.v64 = (__force __be64)nla_get_u64(
103 info->attrs[ILA_ATTR_LOCATOR]);
104
105 if (info->attrs[ILA_ATTR_LOCATOR_MATCH])
106 xp->ip.locator_match.v64 = (__force __be64)nla_get_u64(
107 info->attrs[ILA_ATTR_LOCATOR_MATCH]);
108
109 if (info->attrs[ILA_ATTR_CSUM_MODE])
110 xp->ip.csum_mode = nla_get_u8(info->attrs[ILA_ATTR_CSUM_MODE]);
111 else
112 xp->ip.csum_mode = ILA_CSUM_NO_ACTION;
113
114 if (info->attrs[ILA_ATTR_IDENT_TYPE])
115 xp->ip.ident_type = nla_get_u8(
116 info->attrs[ILA_ATTR_IDENT_TYPE]);
117 else
118 xp->ip.ident_type = ILA_ATYPE_USE_FORMAT;
119
120 if (info->attrs[ILA_ATTR_IFINDEX])
121 xp->ifindex = nla_get_s32(info->attrs[ILA_ATTR_IFINDEX]);
122
123 return 0;
124}
125
126
127static inline struct ila_map *ila_lookup_wildcards(struct ila_addr *iaddr,
128 int ifindex,
129 struct ila_net *ilan)
130{
131 struct ila_map *ila;
132
133 ila = rhashtable_lookup_fast(&ilan->xlat.rhash_table, &iaddr->loc,
134 rht_params);
135 while (ila) {
136 if (!ila_cmp_wildcards(ila, iaddr, ifindex))
137 return ila;
138 ila = rcu_access_pointer(ila->next);
139 }
140
141 return NULL;
142}
143
144
145static inline struct ila_map *ila_lookup_by_params(struct ila_xlat_params *xp,
146 struct ila_net *ilan)
147{
148 struct ila_map *ila;
149
150 ila = rhashtable_lookup_fast(&ilan->xlat.rhash_table,
151 &xp->ip.locator_match,
152 rht_params);
153 while (ila) {
154 if (!ila_cmp_params(ila, xp))
155 return ila;
156 ila = rcu_access_pointer(ila->next);
157 }
158
159 return NULL;
160}
161
162static inline void ila_release(struct ila_map *ila)
163{
164 kfree_rcu(ila, rcu);
165}
166
167static void ila_free_node(struct ila_map *ila)
168{
169 struct ila_map *next;
170
171
172 while (ila) {
173 next = rcu_access_pointer(ila->next);
174 ila_release(ila);
175 ila = next;
176 }
177}
178
179static void ila_free_cb(void *ptr, void *arg)
180{
181 ila_free_node((struct ila_map *)ptr);
182}
183
184static int ila_xlat_addr(struct sk_buff *skb, bool sir2ila);
185
186static unsigned int
187ila_nf_input(void *priv,
188 struct sk_buff *skb,
189 const struct nf_hook_state *state)
190{
191 ila_xlat_addr(skb, false);
192 return NF_ACCEPT;
193}
194
195static const struct nf_hook_ops ila_nf_hook_ops[] = {
196 {
197 .hook = ila_nf_input,
198 .pf = NFPROTO_IPV6,
199 .hooknum = NF_INET_PRE_ROUTING,
200 .priority = -1,
201 },
202};
203
204static int ila_add_mapping(struct net *net, struct ila_xlat_params *xp)
205{
206 struct ila_net *ilan = net_generic(net, ila_net_id);
207 struct ila_map *ila, *head;
208 spinlock_t *lock = ila_get_lock(ilan, xp->ip.locator_match);
209 int err = 0, order;
210
211 if (!ilan->xlat.hooks_registered) {
212
213
214
215 err = nf_register_net_hooks(net, ila_nf_hook_ops,
216 ARRAY_SIZE(ila_nf_hook_ops));
217 if (err)
218 return err;
219
220 ilan->xlat.hooks_registered = true;
221 }
222
223 ila = kzalloc(sizeof(*ila), GFP_KERNEL);
224 if (!ila)
225 return -ENOMEM;
226
227 ila_init_saved_csum(&xp->ip);
228
229 ila->xp = *xp;
230
231 order = ila_order(ila);
232
233 spin_lock(lock);
234
235 head = rhashtable_lookup_fast(&ilan->xlat.rhash_table,
236 &xp->ip.locator_match,
237 rht_params);
238 if (!head) {
239
240 err = rhashtable_lookup_insert_fast(&ilan->xlat.rhash_table,
241 &ila->node, rht_params);
242 } else {
243 struct ila_map *tila = head, *prev = NULL;
244
245 do {
246 if (!ila_cmp_params(tila, xp)) {
247 err = -EEXIST;
248 goto out;
249 }
250
251 if (order > ila_order(tila))
252 break;
253
254 prev = tila;
255 tila = rcu_dereference_protected(tila->next,
256 lockdep_is_held(lock));
257 } while (tila);
258
259 if (prev) {
260
261 RCU_INIT_POINTER(ila->next, tila);
262 rcu_assign_pointer(prev->next, ila);
263 } else {
264
265 RCU_INIT_POINTER(ila->next, head);
266 err = rhashtable_replace_fast(&ilan->xlat.rhash_table,
267 &head->node,
268 &ila->node, rht_params);
269 if (err)
270 goto out;
271 }
272 }
273
274out:
275 spin_unlock(lock);
276
277 if (err)
278 kfree(ila);
279
280 return err;
281}
282
283static int ila_del_mapping(struct net *net, struct ila_xlat_params *xp)
284{
285 struct ila_net *ilan = net_generic(net, ila_net_id);
286 struct ila_map *ila, *head, *prev;
287 spinlock_t *lock = ila_get_lock(ilan, xp->ip.locator_match);
288 int err = -ENOENT;
289
290 spin_lock(lock);
291
292 head = rhashtable_lookup_fast(&ilan->xlat.rhash_table,
293 &xp->ip.locator_match, rht_params);
294 ila = head;
295
296 prev = NULL;
297
298 while (ila) {
299 if (ila_cmp_params(ila, xp)) {
300 prev = ila;
301 ila = rcu_dereference_protected(ila->next,
302 lockdep_is_held(lock));
303 continue;
304 }
305
306 err = 0;
307
308 if (prev) {
309
310 rcu_assign_pointer(prev->next, ila->next);
311 } else {
312
313
314
315 head = rcu_dereference_protected(ila->next,
316 lockdep_is_held(lock));
317 if (head) {
318
319
320
321 err = rhashtable_replace_fast(
322 &ilan->xlat.rhash_table, &ila->node,
323 &head->node, rht_params);
324 if (err)
325 goto out;
326 } else {
327
328 err = rhashtable_remove_fast(
329 &ilan->xlat.rhash_table,
330 &ila->node, rht_params);
331 }
332 }
333
334 ila_release(ila);
335
336 break;
337 }
338
339out:
340 spin_unlock(lock);
341
342 return err;
343}
344
345int ila_xlat_nl_cmd_add_mapping(struct sk_buff *skb, struct genl_info *info)
346{
347 struct net *net = genl_info_net(info);
348 struct ila_xlat_params p;
349 int err;
350
351 err = parse_nl_config(info, &p);
352 if (err)
353 return err;
354
355 return ila_add_mapping(net, &p);
356}
357
358int ila_xlat_nl_cmd_del_mapping(struct sk_buff *skb, struct genl_info *info)
359{
360 struct net *net = genl_info_net(info);
361 struct ila_xlat_params xp;
362 int err;
363
364 err = parse_nl_config(info, &xp);
365 if (err)
366 return err;
367
368 ila_del_mapping(net, &xp);
369
370 return 0;
371}
372
373static inline spinlock_t *lock_from_ila_map(struct ila_net *ilan,
374 struct ila_map *ila)
375{
376 return ila_get_lock(ilan, ila->xp.ip.locator_match);
377}
378
379int ila_xlat_nl_cmd_flush(struct sk_buff *skb, struct genl_info *info)
380{
381 struct net *net = genl_info_net(info);
382 struct ila_net *ilan = net_generic(net, ila_net_id);
383 struct rhashtable_iter iter;
384 struct ila_map *ila;
385 spinlock_t *lock;
386 int ret = 0;
387
388 rhashtable_walk_enter(&ilan->xlat.rhash_table, &iter);
389 rhashtable_walk_start(&iter);
390
391 for (;;) {
392 ila = rhashtable_walk_next(&iter);
393
394 if (IS_ERR(ila)) {
395 if (PTR_ERR(ila) == -EAGAIN)
396 continue;
397 ret = PTR_ERR(ila);
398 goto done;
399 } else if (!ila) {
400 break;
401 }
402
403 lock = lock_from_ila_map(ilan, ila);
404
405 spin_lock(lock);
406
407 ret = rhashtable_remove_fast(&ilan->xlat.rhash_table,
408 &ila->node, rht_params);
409 if (!ret)
410 ila_free_node(ila);
411
412 spin_unlock(lock);
413
414 if (ret)
415 break;
416 }
417
418done:
419 rhashtable_walk_stop(&iter);
420 rhashtable_walk_exit(&iter);
421 return ret;
422}
423
424static int ila_fill_info(struct ila_map *ila, struct sk_buff *msg)
425{
426 if (nla_put_u64_64bit(msg, ILA_ATTR_LOCATOR,
427 (__force u64)ila->xp.ip.locator.v64,
428 ILA_ATTR_PAD) ||
429 nla_put_u64_64bit(msg, ILA_ATTR_LOCATOR_MATCH,
430 (__force u64)ila->xp.ip.locator_match.v64,
431 ILA_ATTR_PAD) ||
432 nla_put_s32(msg, ILA_ATTR_IFINDEX, ila->xp.ifindex) ||
433 nla_put_u8(msg, ILA_ATTR_CSUM_MODE, ila->xp.ip.csum_mode) ||
434 nla_put_u8(msg, ILA_ATTR_IDENT_TYPE, ila->xp.ip.ident_type))
435 return -1;
436
437 return 0;
438}
439
440static int ila_dump_info(struct ila_map *ila,
441 u32 portid, u32 seq, u32 flags,
442 struct sk_buff *skb, u8 cmd)
443{
444 void *hdr;
445
446 hdr = genlmsg_put(skb, portid, seq, &ila_nl_family, flags, cmd);
447 if (!hdr)
448 return -ENOMEM;
449
450 if (ila_fill_info(ila, skb) < 0)
451 goto nla_put_failure;
452
453 genlmsg_end(skb, hdr);
454 return 0;
455
456nla_put_failure:
457 genlmsg_cancel(skb, hdr);
458 return -EMSGSIZE;
459}
460
461int ila_xlat_nl_cmd_get_mapping(struct sk_buff *skb, struct genl_info *info)
462{
463 struct net *net = genl_info_net(info);
464 struct ila_net *ilan = net_generic(net, ila_net_id);
465 struct sk_buff *msg;
466 struct ila_xlat_params xp;
467 struct ila_map *ila;
468 int ret;
469
470 ret = parse_nl_config(info, &xp);
471 if (ret)
472 return ret;
473
474 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
475 if (!msg)
476 return -ENOMEM;
477
478 rcu_read_lock();
479
480 ila = ila_lookup_by_params(&xp, ilan);
481 if (ila) {
482 ret = ila_dump_info(ila,
483 info->snd_portid,
484 info->snd_seq, 0, msg,
485 info->genlhdr->cmd);
486 }
487
488 rcu_read_unlock();
489
490 if (ret < 0)
491 goto out_free;
492
493 return genlmsg_reply(msg, info);
494
495out_free:
496 nlmsg_free(msg);
497 return ret;
498}
499
500struct ila_dump_iter {
501 struct rhashtable_iter rhiter;
502 int skip;
503};
504
505int ila_xlat_nl_dump_start(struct netlink_callback *cb)
506{
507 struct net *net = sock_net(cb->skb->sk);
508 struct ila_net *ilan = net_generic(net, ila_net_id);
509 struct ila_dump_iter *iter;
510
511 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
512 if (!iter)
513 return -ENOMEM;
514
515 rhashtable_walk_enter(&ilan->xlat.rhash_table, &iter->rhiter);
516
517 iter->skip = 0;
518 cb->args[0] = (long)iter;
519
520 return 0;
521}
522
523int ila_xlat_nl_dump_done(struct netlink_callback *cb)
524{
525 struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args[0];
526
527 rhashtable_walk_exit(&iter->rhiter);
528
529 kfree(iter);
530
531 return 0;
532}
533
534int ila_xlat_nl_dump(struct sk_buff *skb, struct netlink_callback *cb)
535{
536 struct ila_dump_iter *iter = (struct ila_dump_iter *)cb->args[0];
537 struct rhashtable_iter *rhiter = &iter->rhiter;
538 int skip = iter->skip;
539 struct ila_map *ila;
540 int ret;
541
542 rhashtable_walk_start(rhiter);
543
544
545 ila = rhashtable_walk_peek(rhiter);
546
547 if (ila && !IS_ERR(ila) && skip) {
548
549
550 while (ila && skip) {
551
552
553
554 ila = rcu_access_pointer(ila->next);
555 skip--;
556 }
557 }
558
559 skip = 0;
560
561 for (;;) {
562 if (IS_ERR(ila)) {
563 ret = PTR_ERR(ila);
564 if (ret == -EAGAIN) {
565
566
567
568
569
570
571 goto out_ret;
572 } else {
573 break;
574 }
575 } else if (!ila) {
576 ret = 0;
577 break;
578 }
579
580 while (ila) {
581 ret = ila_dump_info(ila, NETLINK_CB(cb->skb).portid,
582 cb->nlh->nlmsg_seq, NLM_F_MULTI,
583 skb, ILA_CMD_GET);
584 if (ret)
585 goto out;
586
587 skip++;
588 ila = rcu_access_pointer(ila->next);
589 }
590
591 skip = 0;
592 ila = rhashtable_walk_next(rhiter);
593 }
594
595out:
596 iter->skip = skip;
597 ret = (skb->len ? : ret);
598
599out_ret:
600 rhashtable_walk_stop(rhiter);
601 return ret;
602}
603
604int ila_xlat_init_net(struct net *net)
605{
606 struct ila_net *ilan = net_generic(net, ila_net_id);
607 int err;
608
609 err = alloc_ila_locks(ilan);
610 if (err)
611 return err;
612
613 rhashtable_init(&ilan->xlat.rhash_table, &rht_params);
614
615 return 0;
616}
617
618void ila_xlat_exit_net(struct net *net)
619{
620 struct ila_net *ilan = net_generic(net, ila_net_id);
621
622 rhashtable_free_and_destroy(&ilan->xlat.rhash_table, ila_free_cb, NULL);
623
624 free_bucket_spinlocks(ilan->xlat.locks);
625
626 if (ilan->xlat.hooks_registered)
627 nf_unregister_net_hooks(net, ila_nf_hook_ops,
628 ARRAY_SIZE(ila_nf_hook_ops));
629}
630
631static int ila_xlat_addr(struct sk_buff *skb, bool sir2ila)
632{
633 struct ila_map *ila;
634 struct ipv6hdr *ip6h = ipv6_hdr(skb);
635 struct net *net = dev_net(skb->dev);
636 struct ila_net *ilan = net_generic(net, ila_net_id);
637 struct ila_addr *iaddr = ila_a2i(&ip6h->daddr);
638
639
640
641
642
643
644
645
646 rcu_read_lock();
647
648 ila = ila_lookup_wildcards(iaddr, skb->dev->ifindex, ilan);
649 if (ila)
650 ila_update_ipv6_locator(skb, &ila->xp.ip, sir2ila);
651
652 rcu_read_unlock();
653
654 return 0;
655}
656
