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Linux v2.6.17-rc2
[linux-2.6/next.git] / net / sched / em_meta.c
blob700844d49d795d36acffd22815b5fb4f15ec3ce9
1 /*
2 * net/sched/em_meta.c Metadata ematch
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: Thomas Graf <tgraf@suug.ch>
10 *
11 * ==========================================================================
12 *
13 * The metadata ematch compares two meta objects where each object
14 * represents either a meta value stored in the kernel or a static
15 * value provided by userspace. The objects are not provided by
16 * userspace itself but rather a definition providing the information
17 * to build them. Every object is of a certain type which must be
18 * equal to the object it is being compared to.
19 *
20 * The definition of a objects conists of the type (meta type), a
21 * identifier (meta id) and additional type specific information.
22 * The meta id is either TCF_META_TYPE_VALUE for values provided by
23 * userspace or a index to the meta operations table consisting of
24 * function pointers to type specific meta data collectors returning
25 * the value of the requested meta value.
26 *
27 * lvalue rvalue
28 * +-----------+ +-----------+
29 * | type: INT | | type: INT |
30 * def | id: DEV | | id: VALUE |
31 * | data: | | data: 3 |
32 * +-----------+ +-----------+
33 * | |
34 * ---> meta_ops[INT][DEV](...) |
35 * | |
36 * ----------- |
37 * V V
38 * +-----------+ +-----------+
39 * | type: INT | | type: INT |
40 * obj | id: DEV | | id: VALUE |
41 * | data: 2 |<--data got filled out | data: 3 |
42 * +-----------+ +-----------+
43 * | |
44 * --------------> 2 equals 3 <--------------
45 *
46 * This is a simplified schema, the complexity varies depending
47 * on the meta type. Obviously, the length of the data must also
48 * be provided for non-numeric types.
49 *
50 * Additionaly, type dependant modifiers such as shift operators
51 * or mask may be applied to extend the functionaliy. As of now,
52 * the variable length type supports shifting the byte string to
53 * the right, eating up any number of octets and thus supporting
54 * wildcard interface name comparisons such as "ppp%" matching
55 * ppp0..9.
56 *
57 * NOTE: Certain meta values depend on other subsystems and are
58 * only available if that subsytem is enabled in the kernel.
59 */
60
61 #include <linux/config.h>
62 #include <linux/module.h>
63 #include <linux/types.h>
64 #include <linux/kernel.h>
65 #include <linux/sched.h>
66 #include <linux/string.h>
67 #include <linux/skbuff.h>
68 #include <linux/random.h>
69 #include <linux/tc_ematch/tc_em_meta.h>
70 #include <net/dst.h>
71 #include <net/route.h>
72 #include <net/pkt_cls.h>
73 #include <net/sock.h>
74
75 struct meta_obj
76 {
77 unsigned long value;
78 unsigned int len;
79 };
80
81 struct meta_value
82 {
83 struct tcf_meta_val hdr;
84 unsigned long val;
85 unsigned int len;
86 };
87
88 struct meta_match
89 {
90 struct meta_value lvalue;
91 struct meta_value rvalue;
92 };
93
94 static inline int meta_id(struct meta_value *v)
95 {
96 return TCF_META_ID(v->hdr.kind);
97 }
98
99 static inline int meta_type(struct meta_value *v)
100 {
101 return TCF_META_TYPE(v->hdr.kind);
102 }
103
104 #define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \
105 struct tcf_pkt_info *info, struct meta_value *v, \
106 struct meta_obj *dst, int *err)
107
108 /**************************************************************************
109 * System status & misc
110 **************************************************************************/
111
112 META_COLLECTOR(int_random)
113 {
114 get_random_bytes(&dst->value, sizeof(dst->value));
115 }
116
117 static inline unsigned long fixed_loadavg(int load)
118 {
119 int rnd_load = load + (FIXED_1/200);
120 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT;
121
122 return ((rnd_load >> FSHIFT) * 100) + rnd_frac;
123 }
124
125 META_COLLECTOR(int_loadavg_0)
126 {
127 dst->value = fixed_loadavg(avenrun[0]);
128 }
129
130 META_COLLECTOR(int_loadavg_1)
131 {
132 dst->value = fixed_loadavg(avenrun[1]);
133 }
134
135 META_COLLECTOR(int_loadavg_2)
136 {
137 dst->value = fixed_loadavg(avenrun[2]);
138 }
139
140 /**************************************************************************
141 * Device names & indices
142 **************************************************************************/
143
144 static inline int int_dev(struct net_device *dev, struct meta_obj *dst)
145 {
146 if (unlikely(dev == NULL))
147 return -1;
148
149 dst->value = dev->ifindex;
150 return 0;
151 }
152
153 static inline int var_dev(struct net_device *dev, struct meta_obj *dst)
154 {
155 if (unlikely(dev == NULL))
156 return -1;
157
158 dst->value = (unsigned long) dev->name;
159 dst->len = strlen(dev->name);
160 return 0;
161 }
162
163 META_COLLECTOR(int_dev)
164 {
165 *err = int_dev(skb->dev, dst);
166 }
167
168 META_COLLECTOR(var_dev)
169 {
170 *err = var_dev(skb->dev, dst);
171 }
172
173 /**************************************************************************
174 * skb attributes
175 **************************************************************************/
176
177 META_COLLECTOR(int_priority)
178 {
179 dst->value = skb->priority;
180 }
181
182 META_COLLECTOR(int_protocol)
183 {
184 /* Let userspace take care of the byte ordering */
185 dst->value = skb->protocol;
186 }
187
188 META_COLLECTOR(int_pkttype)
189 {
190 dst->value = skb->pkt_type;
191 }
192
193 META_COLLECTOR(int_pktlen)
194 {
195 dst->value = skb->len;
196 }
197
198 META_COLLECTOR(int_datalen)
199 {
200 dst->value = skb->data_len;
201 }
202
203 META_COLLECTOR(int_maclen)
204 {
205 dst->value = skb->mac_len;
206 }
207
208 /**************************************************************************
209 * Netfilter
210 **************************************************************************/
211
212 META_COLLECTOR(int_nfmark)
213 {
214 #ifdef CONFIG_NETFILTER
215 dst->value = skb->nfmark;
216 #else
217 dst->value = 0;
218 #endif
219 }
220
221 /**************************************************************************
222 * Traffic Control
223 **************************************************************************/
224
225 META_COLLECTOR(int_tcindex)
226 {
227 dst->value = skb->tc_index;
228 }
229
230 /**************************************************************************
231 * Routing
232 **************************************************************************/
233
234 META_COLLECTOR(int_rtclassid)
235 {
236 if (unlikely(skb->dst == NULL))
237 *err = -1;
238 else
239 #ifdef CONFIG_NET_CLS_ROUTE
240 dst->value = skb->dst->tclassid;
241 #else
242 dst->value = 0;
243 #endif
244 }
245
246 META_COLLECTOR(int_rtiif)
247 {
248 if (unlikely(skb->dst == NULL))
249 *err = -1;
250 else
251 dst->value = ((struct rtable*) skb->dst)->fl.iif;
252 }
253
254 /**************************************************************************
255 * Socket Attributes
256 **************************************************************************/
257
258 #define SKIP_NONLOCAL(skb) \
259 if (unlikely(skb->sk == NULL)) { \
260 *err = -1; \
261 return; \
262 }
263
264 META_COLLECTOR(int_sk_family)
265 {
266 SKIP_NONLOCAL(skb);
267 dst->value = skb->sk->sk_family;
268 }
269
270 META_COLLECTOR(int_sk_state)
271 {
272 SKIP_NONLOCAL(skb);
273 dst->value = skb->sk->sk_state;
274 }
275
276 META_COLLECTOR(int_sk_reuse)
277 {
278 SKIP_NONLOCAL(skb);
279 dst->value = skb->sk->sk_reuse;
280 }
281
282 META_COLLECTOR(int_sk_bound_if)
283 {
284 SKIP_NONLOCAL(skb);
285 /* No error if bound_dev_if is 0, legal userspace check */
286 dst->value = skb->sk->sk_bound_dev_if;
287 }
288
289 META_COLLECTOR(var_sk_bound_if)
290 {
291 SKIP_NONLOCAL(skb);
292
293 if (skb->sk->sk_bound_dev_if == 0) {
294 dst->value = (unsigned long) "any";
295 dst->len = 3;
296 } else {
297 struct net_device *dev;
298
299 dev = dev_get_by_index(skb->sk->sk_bound_dev_if);
300 *err = var_dev(dev, dst);
301 if (dev)
302 dev_put(dev);
303 }
304 }
305
306 META_COLLECTOR(int_sk_refcnt)
307 {
308 SKIP_NONLOCAL(skb);
309 dst->value = atomic_read(&skb->sk->sk_refcnt);
310 }
311
312 META_COLLECTOR(int_sk_rcvbuf)
313 {
314 SKIP_NONLOCAL(skb);
315 dst->value = skb->sk->sk_rcvbuf;
316 }
317
318 META_COLLECTOR(int_sk_shutdown)
319 {
320 SKIP_NONLOCAL(skb);
321 dst->value = skb->sk->sk_shutdown;
322 }
323
324 META_COLLECTOR(int_sk_proto)
325 {
326 SKIP_NONLOCAL(skb);
327 dst->value = skb->sk->sk_protocol;
328 }
329
330 META_COLLECTOR(int_sk_type)
331 {
332 SKIP_NONLOCAL(skb);
333 dst->value = skb->sk->sk_type;
334 }
335
336 META_COLLECTOR(int_sk_rmem_alloc)
337 {
338 SKIP_NONLOCAL(skb);
339 dst->value = atomic_read(&skb->sk->sk_rmem_alloc);
340 }
341
342 META_COLLECTOR(int_sk_wmem_alloc)
343 {
344 SKIP_NONLOCAL(skb);
345 dst->value = atomic_read(&skb->sk->sk_wmem_alloc);
346 }
347
348 META_COLLECTOR(int_sk_omem_alloc)
349 {
350 SKIP_NONLOCAL(skb);
351 dst->value = atomic_read(&skb->sk->sk_omem_alloc);
352 }
353
354 META_COLLECTOR(int_sk_rcv_qlen)
355 {
356 SKIP_NONLOCAL(skb);
357 dst->value = skb->sk->sk_receive_queue.qlen;
358 }
359
360 META_COLLECTOR(int_sk_snd_qlen)
361 {
362 SKIP_NONLOCAL(skb);
363 dst->value = skb->sk->sk_write_queue.qlen;
364 }
365
366 META_COLLECTOR(int_sk_wmem_queued)
367 {
368 SKIP_NONLOCAL(skb);
369 dst->value = skb->sk->sk_wmem_queued;
370 }
371
372 META_COLLECTOR(int_sk_fwd_alloc)
373 {
374 SKIP_NONLOCAL(skb);
375 dst->value = skb->sk->sk_forward_alloc;
376 }
377
378 META_COLLECTOR(int_sk_sndbuf)
379 {
380 SKIP_NONLOCAL(skb);
381 dst->value = skb->sk->sk_sndbuf;
382 }
383
384 META_COLLECTOR(int_sk_alloc)
385 {
386 SKIP_NONLOCAL(skb);
387 dst->value = skb->sk->sk_allocation;
388 }
389
390 META_COLLECTOR(int_sk_route_caps)
391 {
392 SKIP_NONLOCAL(skb);
393 dst->value = skb->sk->sk_route_caps;
394 }
395
396 META_COLLECTOR(int_sk_hash)
397 {
398 SKIP_NONLOCAL(skb);
399 dst->value = skb->sk->sk_hash;
400 }
401
402 META_COLLECTOR(int_sk_lingertime)
403 {
404 SKIP_NONLOCAL(skb);
405 dst->value = skb->sk->sk_lingertime / HZ;
406 }
407
408 META_COLLECTOR(int_sk_err_qlen)
409 {
410 SKIP_NONLOCAL(skb);
411 dst->value = skb->sk->sk_error_queue.qlen;
412 }
413
414 META_COLLECTOR(int_sk_ack_bl)
415 {
416 SKIP_NONLOCAL(skb);
417 dst->value = skb->sk->sk_ack_backlog;
418 }
419
420 META_COLLECTOR(int_sk_max_ack_bl)
421 {
422 SKIP_NONLOCAL(skb);
423 dst->value = skb->sk->sk_max_ack_backlog;
424 }
425
426 META_COLLECTOR(int_sk_prio)
427 {
428 SKIP_NONLOCAL(skb);
429 dst->value = skb->sk->sk_priority;
430 }
431
432 META_COLLECTOR(int_sk_rcvlowat)
433 {
434 SKIP_NONLOCAL(skb);
435 dst->value = skb->sk->sk_rcvlowat;
436 }
437
438 META_COLLECTOR(int_sk_rcvtimeo)
439 {
440 SKIP_NONLOCAL(skb);
441 dst->value = skb->sk->sk_rcvtimeo / HZ;
442 }
443
444 META_COLLECTOR(int_sk_sndtimeo)
445 {
446 SKIP_NONLOCAL(skb);
447 dst->value = skb->sk->sk_sndtimeo / HZ;
448 }
449
450 META_COLLECTOR(int_sk_sendmsg_off)
451 {
452 SKIP_NONLOCAL(skb);
453 dst->value = skb->sk->sk_sndmsg_off;
454 }
455
456 META_COLLECTOR(int_sk_write_pend)
457 {
458 SKIP_NONLOCAL(skb);
459 dst->value = skb->sk->sk_write_pending;
460 }
461
462 /**************************************************************************
463 * Meta value collectors assignment table
464 **************************************************************************/
465
466 struct meta_ops
467 {
468 void (*get)(struct sk_buff *, struct tcf_pkt_info *,
469 struct meta_value *, struct meta_obj *, int *);
470 };
471
472 #define META_ID(name) TCF_META_ID_##name
473 #define META_FUNC(name) { .get = meta_##name }
474
475 /* Meta value operations table listing all meta value collectors and
476 * assigns them to a type and meta id. */
477 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = {
478 [TCF_META_TYPE_VAR] = {
479 [META_ID(DEV)] = META_FUNC(var_dev),
480 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if),
481 },
482 [TCF_META_TYPE_INT] = {
483 [META_ID(RANDOM)] = META_FUNC(int_random),
484 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0),
485 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1),
486 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2),
487 [META_ID(DEV)] = META_FUNC(int_dev),
488 [META_ID(PRIORITY)] = META_FUNC(int_priority),
489 [META_ID(PROTOCOL)] = META_FUNC(int_protocol),
490 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype),
491 [META_ID(PKTLEN)] = META_FUNC(int_pktlen),
492 [META_ID(DATALEN)] = META_FUNC(int_datalen),
493 [META_ID(MACLEN)] = META_FUNC(int_maclen),
494 [META_ID(NFMARK)] = META_FUNC(int_nfmark),
495 [META_ID(TCINDEX)] = META_FUNC(int_tcindex),
496 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid),
497 [META_ID(RTIIF)] = META_FUNC(int_rtiif),
498 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family),
499 [META_ID(SK_STATE)] = META_FUNC(int_sk_state),
500 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse),
501 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if),
502 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt),
503 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf),
504 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf),
505 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown),
506 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto),
507 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type),
508 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc),
509 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc),
510 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc),
511 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued),
512 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen),
513 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen),
514 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen),
515 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc),
516 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc),
517 [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps),
518 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash),
519 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime),
520 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl),
521 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl),
522 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio),
523 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat),
524 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo),
525 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo),
526 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off),
527 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend),
528 }
529 };
530
531 static inline struct meta_ops * meta_ops(struct meta_value *val)
532 {
533 return &__meta_ops[meta_type(val)][meta_id(val)];
534 }
535
536 /**************************************************************************
537 * Type specific operations for TCF_META_TYPE_VAR
538 **************************************************************************/
539
540 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b)
541 {
542 int r = a->len - b->len;
543
544 if (r == 0)
545 r = memcmp((void *) a->value, (void *) b->value, a->len);
546
547 return r;
548 }
549
550 static int meta_var_change(struct meta_value *dst, struct rtattr *rta)
551 {
552 int len = RTA_PAYLOAD(rta);
553
554 dst->val = (unsigned long) kmalloc(len, GFP_KERNEL);
555 if (dst->val == 0UL)
556 return -ENOMEM;
557 memcpy((void *) dst->val, RTA_DATA(rta), len);
558 dst->len = len;
559 return 0;
560 }
561
562 static void meta_var_destroy(struct meta_value *v)
563 {
564 kfree((void *) v->val);
565 }
566
567 static void meta_var_apply_extras(struct meta_value *v,
568 struct meta_obj *dst)
569 {
570 int shift = v->hdr.shift;
571
572 if (shift && shift < dst->len)
573 dst->len -= shift;
574 }
575
576 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
577 {
578 if (v->val && v->len)
579 RTA_PUT(skb, tlv, v->len, (void *) v->val);
580 return 0;
581
582 rtattr_failure:
583 return -1;
584 }
585
586 /**************************************************************************
587 * Type specific operations for TCF_META_TYPE_INT
588 **************************************************************************/
589
590 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b)
591 {
592 /* Let gcc optimize it, the unlikely is not really based on
593 * some numbers but jump free code for mismatches seems
594 * more logical. */
595 if (unlikely(a->value == b->value))
596 return 0;
597 else if (a->value < b->value)
598 return -1;
599 else
600 return 1;
601 }
602
603 static int meta_int_change(struct meta_value *dst, struct rtattr *rta)
604 {
605 if (RTA_PAYLOAD(rta) >= sizeof(unsigned long)) {
606 dst->val = *(unsigned long *) RTA_DATA(rta);
607 dst->len = sizeof(unsigned long);
608 } else if (RTA_PAYLOAD(rta) == sizeof(u32)) {
609 dst->val = *(u32 *) RTA_DATA(rta);
610 dst->len = sizeof(u32);
611 } else
612 return -EINVAL;
613
614 return 0;
615 }
616
617 static void meta_int_apply_extras(struct meta_value *v,
618 struct meta_obj *dst)
619 {
620 if (v->hdr.shift)
621 dst->value >>= v->hdr.shift;
622
623 if (v->val)
624 dst->value &= v->val;
625 }
626
627 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
628 {
629 if (v->len == sizeof(unsigned long))
630 RTA_PUT(skb, tlv, sizeof(unsigned long), &v->val);
631 else if (v->len == sizeof(u32)) {
632 u32 d = v->val;
633 RTA_PUT(skb, tlv, sizeof(d), &d);
634 }
635
636 return 0;
637
638 rtattr_failure:
639 return -1;
640 }
641
642 /**************************************************************************
643 * Type specific operations table
644 **************************************************************************/
645
646 struct meta_type_ops
647 {
648 void (*destroy)(struct meta_value *);
649 int (*compare)(struct meta_obj *, struct meta_obj *);
650 int (*change)(struct meta_value *, struct rtattr *);
651 void (*apply_extras)(struct meta_value *, struct meta_obj *);
652 int (*dump)(struct sk_buff *, struct meta_value *, int);
653 };
654
655 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = {
656 [TCF_META_TYPE_VAR] = {
657 .destroy = meta_var_destroy,
658 .compare = meta_var_compare,
659 .change = meta_var_change,
660 .apply_extras = meta_var_apply_extras,
661 .dump = meta_var_dump
662 },
663 [TCF_META_TYPE_INT] = {
664 .compare = meta_int_compare,
665 .change = meta_int_change,
666 .apply_extras = meta_int_apply_extras,
667 .dump = meta_int_dump
668 }
669 };
670
671 static inline struct meta_type_ops * meta_type_ops(struct meta_value *v)
672 {
673 return &__meta_type_ops[meta_type(v)];
674 }
675
676 /**************************************************************************
677 * Core
678 **************************************************************************/
679
680 static inline int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
681 struct meta_value *v, struct meta_obj *dst)
682 {
683 int err = 0;
684
685 if (meta_id(v) == TCF_META_ID_VALUE) {
686 dst->value = v->val;
687 dst->len = v->len;
688 return 0;
689 }
690
691 meta_ops(v)->get(skb, info, v, dst, &err);
692 if (err < 0)
693 return err;
694
695 if (meta_type_ops(v)->apply_extras)
696 meta_type_ops(v)->apply_extras(v, dst);
697
698 return 0;
699 }
700
701 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
702 struct tcf_pkt_info *info)
703 {
704 int r;
705 struct meta_match *meta = (struct meta_match *) m->data;
706 struct meta_obj l_value, r_value;
707
708 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
709 meta_get(skb, info, &meta->rvalue, &r_value) < 0)
710 return 0;
711
712 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
713
714 switch (meta->lvalue.hdr.op) {
715 case TCF_EM_OPND_EQ:
716 return !r;
717 case TCF_EM_OPND_LT:
718 return r < 0;
719 case TCF_EM_OPND_GT:
720 return r > 0;
721 }
722
723 return 0;
724 }
725
726 static inline void meta_delete(struct meta_match *meta)
727 {
728 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
729
730 if (ops && ops->destroy) {
731 ops->destroy(&meta->lvalue);
732 ops->destroy(&meta->rvalue);
733 }
734
735 kfree(meta);
736 }
737
738 static inline int meta_change_data(struct meta_value *dst, struct rtattr *rta)
739 {
740 if (rta) {
741 if (RTA_PAYLOAD(rta) == 0)
742 return -EINVAL;
743
744 return meta_type_ops(dst)->change(dst, rta);
745 }
746
747 return 0;
748 }
749
750 static inline int meta_is_supported(struct meta_value *val)
751 {
752 return (!meta_id(val) || meta_ops(val)->get);
753 }
754
755 static int em_meta_change(struct tcf_proto *tp, void *data, int len,
756 struct tcf_ematch *m)
757 {
758 int err = -EINVAL;
759 struct rtattr *tb[TCA_EM_META_MAX];
760 struct tcf_meta_hdr *hdr;
761 struct meta_match *meta = NULL;
762
763 if (rtattr_parse(tb, TCA_EM_META_MAX, data, len) < 0)
764 goto errout;
765
766 if (tb[TCA_EM_META_HDR-1] == NULL ||
767 RTA_PAYLOAD(tb[TCA_EM_META_HDR-1]) < sizeof(*hdr))
768 goto errout;
769 hdr = RTA_DATA(tb[TCA_EM_META_HDR-1]);
770
771 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
772 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
773 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
774 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
775 goto errout;
776
777 meta = kmalloc(sizeof(*meta), GFP_KERNEL);
778 if (meta == NULL)
779 goto errout;
780 memset(meta, 0, sizeof(*meta));
781
782 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
783 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
784
785 if (!meta_is_supported(&meta->lvalue) ||
786 !meta_is_supported(&meta->rvalue)) {
787 err = -EOPNOTSUPP;
788 goto errout;
789 }
790
791 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE-1]) < 0 ||
792 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE-1]) < 0)
793 goto errout;
794
795 m->datalen = sizeof(*meta);
796 m->data = (unsigned long) meta;
797
798 err = 0;
799 errout:
800 if (err && meta)
801 meta_delete(meta);
802 return err;
803 }
804
805 static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
806 {
807 if (m)
808 meta_delete((struct meta_match *) m->data);
809 }
810
811 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
812 {
813 struct meta_match *meta = (struct meta_match *) em->data;
814 struct tcf_meta_hdr hdr;
815 struct meta_type_ops *ops;
816
817 memset(&hdr, 0, sizeof(hdr));
818 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
819 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
820
821 RTA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr);
822
823 ops = meta_type_ops(&meta->lvalue);
824 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 ||
825 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0)
826 goto rtattr_failure;
827
828 return 0;
829
830 rtattr_failure:
831 return -1;
832 }
833
834 static struct tcf_ematch_ops em_meta_ops = {
835 .kind = TCF_EM_META,
836 .change = em_meta_change,
837 .match = em_meta_match,
838 .destroy = em_meta_destroy,
839 .dump = em_meta_dump,
840 .owner = THIS_MODULE,
841 .link = LIST_HEAD_INIT(em_meta_ops.link)
842 };
843
844 static int __init init_em_meta(void)
845 {
846 return tcf_em_register(&em_meta_ops);
847 }
848
849 static void __exit exit_em_meta(void)
850 {
851 tcf_em_unregister(&em_meta_ops);
852 }
853
854 MODULE_LICENSE("GPL");
855
856 module_init(init_em_meta);
857 module_exit(exit_em_meta);
linux-next