File: /usr/src/linux/net/sched/cls_route.c
1 /*
2 * net/sched/cls_route.c ROUTE4 classifier.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 */
11
12 #include <linux/module.h>
13 #include <linux/config.h>
14 #include <asm/uaccess.h>
15 #include <asm/system.h>
16 #include <asm/bitops.h>
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/string.h>
21 #include <linux/mm.h>
22 #include <linux/socket.h>
23 #include <linux/sockios.h>
24 #include <linux/in.h>
25 #include <linux/errno.h>
26 #include <linux/interrupt.h>
27 #include <linux/if_ether.h>
28 #include <linux/inet.h>
29 #include <linux/netdevice.h>
30 #include <linux/etherdevice.h>
31 #include <linux/notifier.h>
32 #include <net/ip.h>
33 #include <net/route.h>
34 #include <linux/skbuff.h>
35 #include <net/sock.h>
36 #include <net/pkt_sched.h>
37
38 /*
39 1. For now we assume that route tags < 256.
40 It allows to use direct table lookups, instead of hash tables.
41 2. For now we assume that "from TAG" and "fromdev DEV" statements
42 are mutually exclusive.
43 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
44 */
45
46 struct route4_fastmap
47 {
48 struct route4_filter *filter;
49 u32 id;
50 int iif;
51 };
52
53 struct route4_head
54 {
55 struct route4_fastmap fastmap[16];
56 struct route4_bucket *table[256+1];
57 };
58
59 struct route4_bucket
60 {
61 struct route4_filter *ht[16+16+1];
62 };
63
64 struct route4_filter
65 {
66 struct route4_filter *next;
67 u32 id;
68 int iif;
69
70 struct tcf_result res;
71 #ifdef CONFIG_NET_CLS_POLICE
72 struct tcf_police *police;
73 #endif
74
75 u32 handle;
76 struct route4_bucket *bkt;
77 };
78
79 #define ROUTE4_FAILURE ((struct route4_filter*)(-1L))
80
81 static __inline__ int route4_fastmap_hash(u32 id, int iif)
82 {
83 return id&0xF;
84 }
85
86 static void route4_reset_fastmap(struct net_device *dev, struct route4_head *head, u32 id)
87 {
88 spin_lock_bh(&dev->queue_lock);
89 memset(head->fastmap, 0, sizeof(head->fastmap));
90 spin_unlock_bh(&dev->queue_lock);
91 }
92
93 static void __inline__
94 route4_set_fastmap(struct route4_head *head, u32 id, int iif,
95 struct route4_filter *f)
96 {
97 int h = route4_fastmap_hash(id, iif);
98 head->fastmap[h].id = id;
99 head->fastmap[h].iif = iif;
100 head->fastmap[h].filter = f;
101 }
102
103 static __inline__ int route4_hash_to(u32 id)
104 {
105 return id&0xFF;
106 }
107
108 static __inline__ int route4_hash_from(u32 id)
109 {
110 return (id>>16)&0xF;
111 }
112
113 static __inline__ int route4_hash_iif(int iif)
114 {
115 return 16 + ((iif>>16)&0xF);
116 }
117
118 static __inline__ int route4_hash_wild(void)
119 {
120 return 32;
121 }
122
123 #ifdef CONFIG_NET_CLS_POLICE
124 #define IF_ROUTE_POLICE \
125 if (f->police) { \
126 int pol_res = tcf_police(skb, f->police); \
127 if (pol_res >= 0) return pol_res; \
128 dont_cache = 1; \
129 continue; \
130 } \
131 if (!dont_cache)
132 #else
133 #define IF_ROUTE_POLICE
134 #endif
135
136
137 static int route4_classify(struct sk_buff *skb, struct tcf_proto *tp,
138 struct tcf_result *res)
139 {
140 struct route4_head *head = (struct route4_head*)tp->root;
141 struct dst_entry *dst;
142 struct route4_bucket *b;
143 struct route4_filter *f;
144 #ifdef CONFIG_NET_CLS_POLICE
145 int dont_cache = 0;
146 #endif
147 u32 id, h;
148 int iif;
149
150 if ((dst = skb->dst) == NULL)
151 goto failure;
152
153 id = dst->tclassid;
154 if (head == NULL)
155 goto old_method;
156
157 iif = ((struct rtable*)dst)->key.iif;
158
159 h = route4_fastmap_hash(id, iif);
160 if (id == head->fastmap[h].id &&
161 iif == head->fastmap[h].iif &&
162 (f = head->fastmap[h].filter) != NULL) {
163 if (f == ROUTE4_FAILURE)
164 goto failure;
165
166 *res = f->res;
167 return 0;
168 }
169
170 h = route4_hash_to(id);
171
172 restart:
173 if ((b = head->table[h]) != NULL) {
174 f = b->ht[route4_hash_from(id)];
175
176 for ( ; f; f = f->next) {
177 if (f->id == id) {
178 *res = f->res;
179 IF_ROUTE_POLICE route4_set_fastmap(head, id, iif, f);
180 return 0;
181 }
182 }
183
184 for (f = b->ht[route4_hash_iif(iif)]; f; f = f->next) {
185 if (f->iif == iif) {
186 *res = f->res;
187 IF_ROUTE_POLICE route4_set_fastmap(head, id, iif, f);
188 return 0;
189 }
190 }
191
192 for (f = b->ht[route4_hash_wild()]; f; f = f->next) {
193 *res = f->res;
194 IF_ROUTE_POLICE route4_set_fastmap(head, id, iif, f);
195 return 0;
196 }
197
198 }
199 if (h < 256) {
200 h = 256;
201 id &= ~0xFFFF;
202 goto restart;
203 }
204
205 #ifdef CONFIG_NET_CLS_POLICE
206 if (!dont_cache)
207 #endif
208 route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
209 failure:
210 return -1;
211
212 old_method:
213 if (id && (TC_H_MAJ(id) == 0 ||
214 !(TC_H_MAJ(id^tp->q->handle)))) {
215 res->classid = id;
216 res->class = 0;
217 return 0;
218 }
219 return -1;
220 }
221
222 static u32 to_hash(u32 id)
223 {
224 u32 h = id&0xFF;
225 if (id&0x8000)
226 h += 256;
227 return h;
228 }
229
230 static u32 from_hash(u32 id)
231 {
232 id &= 0xFFFF;
233 if (id == 0xFFFF)
234 return 32;
235 if (!(id & 0x8000)) {
236 if (id > 255)
237 return 256;
238 return id&0xF;
239 }
240 return 16 + (id&0xF);
241 }
242
243 static unsigned long route4_get(struct tcf_proto *tp, u32 handle)
244 {
245 struct route4_head *head = (struct route4_head*)tp->root;
246 struct route4_bucket *b;
247 struct route4_filter *f;
248 unsigned h1, h2;
249
250 if (!head)
251 return 0;
252
253 h1 = to_hash(handle);
254 if (h1 > 256)
255 return 0;
256
257 h2 = from_hash(handle>>16);
258 if (h2 > 32)
259 return 0;
260
261 if ((b = head->table[h1]) != NULL) {
262 for (f = b->ht[h2]; f; f = f->next)
263 if (f->handle == handle)
264 return (unsigned long)f;
265 }
266 return 0;
267 }
268
269 static void route4_put(struct tcf_proto *tp, unsigned long f)
270 {
271 }
272
273 static int route4_init(struct tcf_proto *tp)
274 {
275 MOD_INC_USE_COUNT;
276 return 0;
277 }
278
279 static void route4_destroy(struct tcf_proto *tp)
280 {
281 struct route4_head *head = xchg(&tp->root, NULL);
282 int h1, h2;
283
284 if (head == NULL) {
285 MOD_DEC_USE_COUNT;
286 return;
287 }
288
289 for (h1=0; h1<=256; h1++) {
290 struct route4_bucket *b;
291
292 if ((b = head->table[h1]) != NULL) {
293 for (h2=0; h2<=32; h2++) {
294 struct route4_filter *f;
295
296 while ((f = b->ht[h2]) != NULL) {
297 unsigned long cl;
298
299 b->ht[h2] = f->next;
300 if ((cl = __cls_set_class(&f->res.class, 0)) != 0)
301 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
302 #ifdef CONFIG_NET_CLS_POLICE
303 tcf_police_release(f->police);
304 #endif
305 kfree(f);
306 }
307 }
308 kfree(b);
309 }
310 }
311 kfree(head);
312 MOD_DEC_USE_COUNT;
313 }
314
315 static int route4_delete(struct tcf_proto *tp, unsigned long arg)
316 {
317 struct route4_head *head = (struct route4_head*)tp->root;
318 struct route4_filter **fp, *f = (struct route4_filter*)arg;
319 unsigned h = 0;
320 struct route4_bucket *b;
321 int i;
322
323 if (!head || !f)
324 return -EINVAL;
325
326 h = f->handle;
327 b = f->bkt;
328
329 for (fp = &b->ht[from_hash(h>>16)]; *fp; fp = &(*fp)->next) {
330 if (*fp == f) {
331 unsigned long cl;
332
333 tcf_tree_lock(tp);
334 *fp = f->next;
335 tcf_tree_unlock(tp);
336
337 route4_reset_fastmap(tp->q->dev, head, f->id);
338
339 if ((cl = cls_set_class(tp, &f->res.class, 0)) != 0)
340 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
341
342 #ifdef CONFIG_NET_CLS_POLICE
343 tcf_police_release(f->police);
344 #endif
345 kfree(f);
346
347 /* Strip tree */
348
349 for (i=0; i<=32; i++)
350 if (b->ht[i])
351 return 0;
352
353 /* OK, session has no flows */
354 tcf_tree_lock(tp);
355 head->table[to_hash(h)] = NULL;
356 tcf_tree_unlock(tp);
357
358 kfree(b);
359 return 0;
360 }
361 }
362 return 0;
363 }
364
365 static int route4_change(struct tcf_proto *tp, unsigned long base,
366 u32 handle,
367 struct rtattr **tca,
368 unsigned long *arg)
369 {
370 struct route4_head *head = tp->root;
371 struct route4_filter *f, *f1, **ins_f;
372 struct route4_bucket *b;
373 struct rtattr *opt = tca[TCA_OPTIONS-1];
374 struct rtattr *tb[TCA_ROUTE4_MAX];
375 unsigned h1, h2;
376 int err;
377
378 if (opt == NULL)
379 return handle ? -EINVAL : 0;
380
381 if (rtattr_parse(tb, TCA_ROUTE4_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)
382 return -EINVAL;
383
384 if ((f = (struct route4_filter*)*arg) != NULL) {
385 /* Node exists: adjust only classid */
386
387 if (f->handle != handle && handle)
388 return -EINVAL;
389 if (tb[TCA_ROUTE4_CLASSID-1]) {
390 unsigned long cl;
391
392 f->res.classid = *(u32*)RTA_DATA(tb[TCA_ROUTE4_CLASSID-1]);
393 cl = cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
394 if (cl)
395 tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
396 }
397 #ifdef CONFIG_NET_CLS_POLICE
398 if (tb[TCA_ROUTE4_POLICE-1]) {
399 struct tcf_police *police = tcf_police_locate(tb[TCA_ROUTE4_POLICE-1], tca[TCA_RATE-1]);
400
401 tcf_tree_lock(tp);
402 police = xchg(&f->police, police);
403 tcf_tree_unlock(tp);
404
405 tcf_police_release(police);
406 }
407 #endif
408 return 0;
409 }
410
411 /* Now more serious part... */
412
413 if (head == NULL) {
414 head = kmalloc(sizeof(struct route4_head), GFP_KERNEL);
415 if (head == NULL)
416 return -ENOBUFS;
417 memset(head, 0, sizeof(struct route4_head));
418
419 tcf_tree_lock(tp);
420 tp->root = head;
421 tcf_tree_unlock(tp);
422 }
423
424 f = kmalloc(sizeof(struct route4_filter), GFP_KERNEL);
425 if (f == NULL)
426 return -ENOBUFS;
427
428 memset(f, 0, sizeof(*f));
429
430 err = -EINVAL;
431 f->handle = 0x8000;
432 if (tb[TCA_ROUTE4_TO-1]) {
433 if (handle&0x8000)
434 goto errout;
435 if (RTA_PAYLOAD(tb[TCA_ROUTE4_TO-1]) < 4)
436 goto errout;
437 f->id = *(u32*)RTA_DATA(tb[TCA_ROUTE4_TO-1]);
438 if (f->id > 0xFF)
439 goto errout;
440 f->handle = f->id;
441 }
442 if (tb[TCA_ROUTE4_FROM-1]) {
443 u32 sid;
444 if (tb[TCA_ROUTE4_IIF-1])
445 goto errout;
446 if (RTA_PAYLOAD(tb[TCA_ROUTE4_FROM-1]) < 4)
447 goto errout;
448 sid = (*(u32*)RTA_DATA(tb[TCA_ROUTE4_FROM-1]));
449 if (sid > 0xFF)
450 goto errout;
451 f->handle |= sid<<16;
452 f->id |= sid<<16;
453 } else if (tb[TCA_ROUTE4_IIF-1]) {
454 if (RTA_PAYLOAD(tb[TCA_ROUTE4_IIF-1]) < 4)
455 goto errout;
456 f->iif = *(u32*)RTA_DATA(tb[TCA_ROUTE4_IIF-1]);
457 if (f->iif > 0x7FFF)
458 goto errout;
459 f->handle |= (f->iif|0x8000)<<16;
460 } else
461 f->handle |= 0xFFFF<<16;
462
463 if (handle) {
464 f->handle |= handle&0x7F00;
465 if (f->handle != handle)
466 goto errout;
467 }
468
469 if (tb[TCA_ROUTE4_CLASSID-1]) {
470 if (RTA_PAYLOAD(tb[TCA_ROUTE4_CLASSID-1]) < 4)
471 goto errout;
472 f->res.classid = *(u32*)RTA_DATA(tb[TCA_ROUTE4_CLASSID-1]);
473 }
474
475 h1 = to_hash(f->handle);
476 if ((b = head->table[h1]) == NULL) {
477 err = -ENOBUFS;
478 b = kmalloc(sizeof(struct route4_bucket), GFP_KERNEL);
479 if (b == NULL)
480 goto errout;
481 memset(b, 0, sizeof(*b));
482
483 tcf_tree_lock(tp);
484 head->table[h1] = b;
485 tcf_tree_unlock(tp);
486 }
487 f->bkt = b;
488
489 err = -EEXIST;
490 h2 = from_hash(f->handle>>16);
491 for (ins_f = &b->ht[h2]; (f1=*ins_f) != NULL; ins_f = &f1->next) {
492 if (f->handle < f1->handle)
493 break;
494 if (f1->handle == f->handle)
495 goto errout;
496 }
497
498 cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
499 #ifdef CONFIG_NET_CLS_POLICE
500 if (tb[TCA_ROUTE4_POLICE-1])
501 f->police = tcf_police_locate(tb[TCA_ROUTE4_POLICE-1], tca[TCA_RATE-1]);
502 #endif
503
504 f->next = f1;
505 tcf_tree_lock(tp);
506 *ins_f = f;
507 tcf_tree_unlock(tp);
508
509 route4_reset_fastmap(tp->q->dev, head, f->id);
510 *arg = (unsigned long)f;
511 return 0;
512
513 errout:
514 if (f)
515 kfree(f);
516 return err;
517 }
518
519 static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg)
520 {
521 struct route4_head *head = tp->root;
522 unsigned h, h1;
523
524 if (head == NULL)
525 arg->stop = 1;
526
527 if (arg->stop)
528 return;
529
530 for (h = 0; h <= 256; h++) {
531 struct route4_bucket *b = head->table[h];
532
533 if (b) {
534 for (h1 = 0; h1 <= 32; h1++) {
535 struct route4_filter *f;
536
537 for (f = b->ht[h1]; f; f = f->next) {
538 if (arg->count < arg->skip) {
539 arg->count++;
540 continue;
541 }
542 if (arg->fn(tp, (unsigned long)f, arg) < 0) {
543 arg->stop = 1;
544 break;
545 }
546 arg->count++;
547 }
548 }
549 }
550 }
551 }
552
553 #ifdef CONFIG_RTNETLINK
554 static int route4_dump(struct tcf_proto *tp, unsigned long fh,
555 struct sk_buff *skb, struct tcmsg *t)
556 {
557 struct route4_filter *f = (struct route4_filter*)fh;
558 unsigned char *b = skb->tail;
559 struct rtattr *rta;
560 u32 id;
561
562 if (f == NULL)
563 return skb->len;
564
565 t->tcm_handle = f->handle;
566
567 rta = (struct rtattr*)b;
568 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
569
570 if (!(f->handle&0x8000)) {
571 id = f->id&0xFF;
572 RTA_PUT(skb, TCA_ROUTE4_TO, sizeof(id), &id);
573 }
574 if (f->handle&0x80000000) {
575 if ((f->handle>>16) != 0xFFFF)
576 RTA_PUT(skb, TCA_ROUTE4_IIF, sizeof(f->iif), &f->iif);
577 } else {
578 id = f->id>>16;
579 RTA_PUT(skb, TCA_ROUTE4_FROM, sizeof(id), &id);
580 }
581 if (f->res.classid)
582 RTA_PUT(skb, TCA_ROUTE4_CLASSID, 4, &f->res.classid);
583 #ifdef CONFIG_NET_CLS_POLICE
584 if (f->police) {
585 struct rtattr * p_rta = (struct rtattr*)skb->tail;
586
587 RTA_PUT(skb, TCA_ROUTE4_POLICE, 0, NULL);
588
589 if (tcf_police_dump(skb, f->police) < 0)
590 goto rtattr_failure;
591
592 p_rta->rta_len = skb->tail - (u8*)p_rta;
593 }
594 #endif
595
596 rta->rta_len = skb->tail - b;
597 #ifdef CONFIG_NET_CLS_POLICE
598 if (f->police) {
599 if (qdisc_copy_stats(skb, &f->police->stats))
600 goto rtattr_failure;
601 }
602 #endif
603 return skb->len;
604
605 rtattr_failure:
606 skb_trim(skb, b - skb->data);
607 return -1;
608 }
609 #endif
610
611 struct tcf_proto_ops cls_route4_ops = {
612 NULL,
613 "route",
614 route4_classify,
615 route4_init,
616 route4_destroy,
617
618 route4_get,
619 route4_put,
620 route4_change,
621 route4_delete,
622 route4_walk,
623 #ifdef CONFIG_RTNETLINK
624 route4_dump
625 #else
626 NULL
627 #endif
628 };
629
630 #ifdef MODULE
631 int init_module(void)
632 {
633 return register_tcf_proto_ops(&cls_route4_ops);
634 }
635
636 void cleanup_module(void)
637 {
638 unregister_tcf_proto_ops(&cls_route4_ops);
639 }
640 #endif
641