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writeback: split writeback_inodes_wb
[linux-2.6/next.git] / net / sched / em_meta.c
blob3bcac8aa333c2a322fb7283ce0803480e893d5d4
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 subsystem is enabled in the kernel.
59 */
60
61 #include <linux/slab.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/if_vlan.h>
70 #include <linux/tc_ematch/tc_em_meta.h>
71 #include <net/dst.h>
72 #include <net/route.h>
73 #include <net/pkt_cls.h>
74 #include <net/sock.h>
75
76 struct meta_obj
77 {
78 unsigned long value;
79 unsigned int len;
80 };
81
82 struct meta_value
83 {
84 struct tcf_meta_val hdr;
85 unsigned long val;
86 unsigned int len;
87 };
88
89 struct meta_match
90 {
91 struct meta_value lvalue;
92 struct meta_value rvalue;
93 };
94
95 static inline int meta_id(struct meta_value *v)
96 {
97 return TCF_META_ID(v->hdr.kind);
98 }
99
100 static inline int meta_type(struct meta_value *v)
101 {
102 return TCF_META_TYPE(v->hdr.kind);
103 }
104
105 #define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \
106 struct tcf_pkt_info *info, struct meta_value *v, \
107 struct meta_obj *dst, int *err)
108
109 /**************************************************************************
110 * System status & misc
111 **************************************************************************/
112
113 META_COLLECTOR(int_random)
114 {
115 get_random_bytes(&dst->value, sizeof(dst->value));
116 }
117
118 static inline unsigned long fixed_loadavg(int load)
119 {
120 int rnd_load = load + (FIXED_1/200);
121 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT;
122
123 return ((rnd_load >> FSHIFT) * 100) + rnd_frac;
124 }
125
126 META_COLLECTOR(int_loadavg_0)
127 {
128 dst->value = fixed_loadavg(avenrun[0]);
129 }
130
131 META_COLLECTOR(int_loadavg_1)
132 {
133 dst->value = fixed_loadavg(avenrun[1]);
134 }
135
136 META_COLLECTOR(int_loadavg_2)
137 {
138 dst->value = fixed_loadavg(avenrun[2]);
139 }
140
141 /**************************************************************************
142 * Device names & indices
143 **************************************************************************/
144
145 static inline int int_dev(struct net_device *dev, struct meta_obj *dst)
146 {
147 if (unlikely(dev == NULL))
148 return -1;
149
150 dst->value = dev->ifindex;
151 return 0;
152 }
153
154 static inline int var_dev(struct net_device *dev, struct meta_obj *dst)
155 {
156 if (unlikely(dev == NULL))
157 return -1;
158
159 dst->value = (unsigned long) dev->name;
160 dst->len = strlen(dev->name);
161 return 0;
162 }
163
164 META_COLLECTOR(int_dev)
165 {
166 *err = int_dev(skb->dev, dst);
167 }
168
169 META_COLLECTOR(var_dev)
170 {
171 *err = var_dev(skb->dev, dst);
172 }
173
174 /**************************************************************************
175 * vlan tag
176 **************************************************************************/
177
178 META_COLLECTOR(int_vlan_tag)
179 {
180 unsigned short tag;
181
182 tag = vlan_tx_tag_get(skb);
183 if (!tag && __vlan_get_tag(skb, &tag))
184 *err = -1;
185 else
186 dst->value = tag;
187 }
188
189
190
191 /**************************************************************************
192 * skb attributes
193 **************************************************************************/
194
195 META_COLLECTOR(int_priority)
196 {
197 dst->value = skb->priority;
198 }
199
200 META_COLLECTOR(int_protocol)
201 {
202 /* Let userspace take care of the byte ordering */
203 dst->value = skb->protocol;
204 }
205
206 META_COLLECTOR(int_pkttype)
207 {
208 dst->value = skb->pkt_type;
209 }
210
211 META_COLLECTOR(int_pktlen)
212 {
213 dst->value = skb->len;
214 }
215
216 META_COLLECTOR(int_datalen)
217 {
218 dst->value = skb->data_len;
219 }
220
221 META_COLLECTOR(int_maclen)
222 {
223 dst->value = skb->mac_len;
224 }
225
226 /**************************************************************************
227 * Netfilter
228 **************************************************************************/
229
230 META_COLLECTOR(int_mark)
231 {
232 dst->value = skb->mark;
233 }
234
235 /**************************************************************************
236 * Traffic Control
237 **************************************************************************/
238
239 META_COLLECTOR(int_tcindex)
240 {
241 dst->value = skb->tc_index;
242 }
243
244 /**************************************************************************
245 * Routing
246 **************************************************************************/
247
248 META_COLLECTOR(int_rtclassid)
249 {
250 if (unlikely(skb_dst(skb) == NULL))
251 *err = -1;
252 else
253 #ifdef CONFIG_NET_CLS_ROUTE
254 dst->value = skb_dst(skb)->tclassid;
255 #else
256 dst->value = 0;
257 #endif
258 }
259
260 META_COLLECTOR(int_rtiif)
261 {
262 if (unlikely(skb_rtable(skb) == NULL))
263 *err = -1;
264 else
265 dst->value = skb_rtable(skb)->fl.iif;
266 }
267
268 /**************************************************************************
269 * Socket Attributes
270 **************************************************************************/
271
272 #define SKIP_NONLOCAL(skb) \
273 if (unlikely(skb->sk == NULL)) { \
274 *err = -1; \
275 return; \
276 }
277
278 META_COLLECTOR(int_sk_family)
279 {
280 SKIP_NONLOCAL(skb);
281 dst->value = skb->sk->sk_family;
282 }
283
284 META_COLLECTOR(int_sk_state)
285 {
286 SKIP_NONLOCAL(skb);
287 dst->value = skb->sk->sk_state;
288 }
289
290 META_COLLECTOR(int_sk_reuse)
291 {
292 SKIP_NONLOCAL(skb);
293 dst->value = skb->sk->sk_reuse;
294 }
295
296 META_COLLECTOR(int_sk_bound_if)
297 {
298 SKIP_NONLOCAL(skb);
299 /* No error if bound_dev_if is 0, legal userspace check */
300 dst->value = skb->sk->sk_bound_dev_if;
301 }
302
303 META_COLLECTOR(var_sk_bound_if)
304 {
305 SKIP_NONLOCAL(skb);
306
307 if (skb->sk->sk_bound_dev_if == 0) {
308 dst->value = (unsigned long) "any";
309 dst->len = 3;
310 } else {
311 struct net_device *dev;
312
313 rcu_read_lock();
314 dev = dev_get_by_index_rcu(sock_net(skb->sk),
315 skb->sk->sk_bound_dev_if);
316 *err = var_dev(dev, dst);
317 rcu_read_unlock();
318 }
319 }
320
321 META_COLLECTOR(int_sk_refcnt)
322 {
323 SKIP_NONLOCAL(skb);
324 dst->value = atomic_read(&skb->sk->sk_refcnt);
325 }
326
327 META_COLLECTOR(int_sk_rcvbuf)
328 {
329 SKIP_NONLOCAL(skb);
330 dst->value = skb->sk->sk_rcvbuf;
331 }
332
333 META_COLLECTOR(int_sk_shutdown)
334 {
335 SKIP_NONLOCAL(skb);
336 dst->value = skb->sk->sk_shutdown;
337 }
338
339 META_COLLECTOR(int_sk_proto)
340 {
341 SKIP_NONLOCAL(skb);
342 dst->value = skb->sk->sk_protocol;
343 }
344
345 META_COLLECTOR(int_sk_type)
346 {
347 SKIP_NONLOCAL(skb);
348 dst->value = skb->sk->sk_type;
349 }
350
351 META_COLLECTOR(int_sk_rmem_alloc)
352 {
353 SKIP_NONLOCAL(skb);
354 dst->value = sk_rmem_alloc_get(skb->sk);
355 }
356
357 META_COLLECTOR(int_sk_wmem_alloc)
358 {
359 SKIP_NONLOCAL(skb);
360 dst->value = sk_wmem_alloc_get(skb->sk);
361 }
362
363 META_COLLECTOR(int_sk_omem_alloc)
364 {
365 SKIP_NONLOCAL(skb);
366 dst->value = atomic_read(&skb->sk->sk_omem_alloc);
367 }
368
369 META_COLLECTOR(int_sk_rcv_qlen)
370 {
371 SKIP_NONLOCAL(skb);
372 dst->value = skb->sk->sk_receive_queue.qlen;
373 }
374
375 META_COLLECTOR(int_sk_snd_qlen)
376 {
377 SKIP_NONLOCAL(skb);
378 dst->value = skb->sk->sk_write_queue.qlen;
379 }
380
381 META_COLLECTOR(int_sk_wmem_queued)
382 {
383 SKIP_NONLOCAL(skb);
384 dst->value = skb->sk->sk_wmem_queued;
385 }
386
387 META_COLLECTOR(int_sk_fwd_alloc)
388 {
389 SKIP_NONLOCAL(skb);
390 dst->value = skb->sk->sk_forward_alloc;
391 }
392
393 META_COLLECTOR(int_sk_sndbuf)
394 {
395 SKIP_NONLOCAL(skb);
396 dst->value = skb->sk->sk_sndbuf;
397 }
398
399 META_COLLECTOR(int_sk_alloc)
400 {
401 SKIP_NONLOCAL(skb);
402 dst->value = skb->sk->sk_allocation;
403 }
404
405 META_COLLECTOR(int_sk_route_caps)
406 {
407 SKIP_NONLOCAL(skb);
408 dst->value = skb->sk->sk_route_caps;
409 }
410
411 META_COLLECTOR(int_sk_hash)
412 {
413 SKIP_NONLOCAL(skb);
414 dst->value = skb->sk->sk_hash;
415 }
416
417 META_COLLECTOR(int_sk_lingertime)
418 {
419 SKIP_NONLOCAL(skb);
420 dst->value = skb->sk->sk_lingertime / HZ;
421 }
422
423 META_COLLECTOR(int_sk_err_qlen)
424 {
425 SKIP_NONLOCAL(skb);
426 dst->value = skb->sk->sk_error_queue.qlen;
427 }
428
429 META_COLLECTOR(int_sk_ack_bl)
430 {
431 SKIP_NONLOCAL(skb);
432 dst->value = skb->sk->sk_ack_backlog;
433 }
434
435 META_COLLECTOR(int_sk_max_ack_bl)
436 {
437 SKIP_NONLOCAL(skb);
438 dst->value = skb->sk->sk_max_ack_backlog;
439 }
440
441 META_COLLECTOR(int_sk_prio)
442 {
443 SKIP_NONLOCAL(skb);
444 dst->value = skb->sk->sk_priority;
445 }
446
447 META_COLLECTOR(int_sk_rcvlowat)
448 {
449 SKIP_NONLOCAL(skb);
450 dst->value = skb->sk->sk_rcvlowat;
451 }
452
453 META_COLLECTOR(int_sk_rcvtimeo)
454 {
455 SKIP_NONLOCAL(skb);
456 dst->value = skb->sk->sk_rcvtimeo / HZ;
457 }
458
459 META_COLLECTOR(int_sk_sndtimeo)
460 {
461 SKIP_NONLOCAL(skb);
462 dst->value = skb->sk->sk_sndtimeo / HZ;
463 }
464
465 META_COLLECTOR(int_sk_sendmsg_off)
466 {
467 SKIP_NONLOCAL(skb);
468 dst->value = skb->sk->sk_sndmsg_off;
469 }
470
471 META_COLLECTOR(int_sk_write_pend)
472 {
473 SKIP_NONLOCAL(skb);
474 dst->value = skb->sk->sk_write_pending;
475 }
476
477 /**************************************************************************
478 * Meta value collectors assignment table
479 **************************************************************************/
480
481 struct meta_ops
482 {
483 void (*get)(struct sk_buff *, struct tcf_pkt_info *,
484 struct meta_value *, struct meta_obj *, int *);
485 };
486
487 #define META_ID(name) TCF_META_ID_##name
488 #define META_FUNC(name) { .get = meta_##name }
489
490 /* Meta value operations table listing all meta value collectors and
491 * assigns them to a type and meta id. */
492 static struct meta_ops __meta_ops[TCF_META_TYPE_MAX+1][TCF_META_ID_MAX+1] = {
493 [TCF_META_TYPE_VAR] = {
494 [META_ID(DEV)] = META_FUNC(var_dev),
495 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if),
496 },
497 [TCF_META_TYPE_INT] = {
498 [META_ID(RANDOM)] = META_FUNC(int_random),
499 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0),
500 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1),
501 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2),
502 [META_ID(DEV)] = META_FUNC(int_dev),
503 [META_ID(PRIORITY)] = META_FUNC(int_priority),
504 [META_ID(PROTOCOL)] = META_FUNC(int_protocol),
505 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype),
506 [META_ID(PKTLEN)] = META_FUNC(int_pktlen),
507 [META_ID(DATALEN)] = META_FUNC(int_datalen),
508 [META_ID(MACLEN)] = META_FUNC(int_maclen),
509 [META_ID(NFMARK)] = META_FUNC(int_mark),
510 [META_ID(TCINDEX)] = META_FUNC(int_tcindex),
511 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid),
512 [META_ID(RTIIF)] = META_FUNC(int_rtiif),
513 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family),
514 [META_ID(SK_STATE)] = META_FUNC(int_sk_state),
515 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse),
516 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if),
517 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt),
518 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf),
519 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf),
520 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown),
521 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto),
522 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type),
523 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc),
524 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc),
525 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc),
526 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued),
527 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen),
528 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen),
529 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen),
530 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc),
531 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc),
532 [META_ID(SK_ROUTE_CAPS)] = META_FUNC(int_sk_route_caps),
533 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash),
534 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime),
535 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl),
536 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl),
537 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio),
538 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat),
539 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo),
540 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo),
541 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off),
542 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend),
543 [META_ID(VLAN_TAG)] = META_FUNC(int_vlan_tag),
544 }
545 };
546
547 static inline struct meta_ops * meta_ops(struct meta_value *val)
548 {
549 return &__meta_ops[meta_type(val)][meta_id(val)];
550 }
551
552 /**************************************************************************
553 * Type specific operations for TCF_META_TYPE_VAR
554 **************************************************************************/
555
556 static int meta_var_compare(struct meta_obj *a, struct meta_obj *b)
557 {
558 int r = a->len - b->len;
559
560 if (r == 0)
561 r = memcmp((void *) a->value, (void *) b->value, a->len);
562
563 return r;
564 }
565
566 static int meta_var_change(struct meta_value *dst, struct nlattr *nla)
567 {
568 int len = nla_len(nla);
569
570 dst->val = (unsigned long)kmemdup(nla_data(nla), len, GFP_KERNEL);
571 if (dst->val == 0UL)
572 return -ENOMEM;
573 dst->len = len;
574 return 0;
575 }
576
577 static void meta_var_destroy(struct meta_value *v)
578 {
579 kfree((void *) v->val);
580 }
581
582 static void meta_var_apply_extras(struct meta_value *v,
583 struct meta_obj *dst)
584 {
585 int shift = v->hdr.shift;
586
587 if (shift && shift < dst->len)
588 dst->len -= shift;
589 }
590
591 static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
592 {
593 if (v->val && v->len)
594 NLA_PUT(skb, tlv, v->len, (void *) v->val);
595 return 0;
596
597 nla_put_failure:
598 return -1;
599 }
600
601 /**************************************************************************
602 * Type specific operations for TCF_META_TYPE_INT
603 **************************************************************************/
604
605 static int meta_int_compare(struct meta_obj *a, struct meta_obj *b)
606 {
607 /* Let gcc optimize it, the unlikely is not really based on
608 * some numbers but jump free code for mismatches seems
609 * more logical. */
610 if (unlikely(a->value == b->value))
611 return 0;
612 else if (a->value < b->value)
613 return -1;
614 else
615 return 1;
616 }
617
618 static int meta_int_change(struct meta_value *dst, struct nlattr *nla)
619 {
620 if (nla_len(nla) >= sizeof(unsigned long)) {
621 dst->val = *(unsigned long *) nla_data(nla);
622 dst->len = sizeof(unsigned long);
623 } else if (nla_len(nla) == sizeof(u32)) {
624 dst->val = nla_get_u32(nla);
625 dst->len = sizeof(u32);
626 } else
627 return -EINVAL;
628
629 return 0;
630 }
631
632 static void meta_int_apply_extras(struct meta_value *v,
633 struct meta_obj *dst)
634 {
635 if (v->hdr.shift)
636 dst->value >>= v->hdr.shift;
637
638 if (v->val)
639 dst->value &= v->val;
640 }
641
642 static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
643 {
644 if (v->len == sizeof(unsigned long))
645 NLA_PUT(skb, tlv, sizeof(unsigned long), &v->val);
646 else if (v->len == sizeof(u32)) {
647 NLA_PUT_U32(skb, tlv, v->val);
648 }
649
650 return 0;
651
652 nla_put_failure:
653 return -1;
654 }
655
656 /**************************************************************************
657 * Type specific operations table
658 **************************************************************************/
659
660 struct meta_type_ops
661 {
662 void (*destroy)(struct meta_value *);
663 int (*compare)(struct meta_obj *, struct meta_obj *);
664 int (*change)(struct meta_value *, struct nlattr *);
665 void (*apply_extras)(struct meta_value *, struct meta_obj *);
666 int (*dump)(struct sk_buff *, struct meta_value *, int);
667 };
668
669 static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX+1] = {
670 [TCF_META_TYPE_VAR] = {
671 .destroy = meta_var_destroy,
672 .compare = meta_var_compare,
673 .change = meta_var_change,
674 .apply_extras = meta_var_apply_extras,
675 .dump = meta_var_dump
676 },
677 [TCF_META_TYPE_INT] = {
678 .compare = meta_int_compare,
679 .change = meta_int_change,
680 .apply_extras = meta_int_apply_extras,
681 .dump = meta_int_dump
682 }
683 };
684
685 static inline struct meta_type_ops * meta_type_ops(struct meta_value *v)
686 {
687 return &__meta_type_ops[meta_type(v)];
688 }
689
690 /**************************************************************************
691 * Core
692 **************************************************************************/
693
694 static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
695 struct meta_value *v, struct meta_obj *dst)
696 {
697 int err = 0;
698
699 if (meta_id(v) == TCF_META_ID_VALUE) {
700 dst->value = v->val;
701 dst->len = v->len;
702 return 0;
703 }
704
705 meta_ops(v)->get(skb, info, v, dst, &err);
706 if (err < 0)
707 return err;
708
709 if (meta_type_ops(v)->apply_extras)
710 meta_type_ops(v)->apply_extras(v, dst);
711
712 return 0;
713 }
714
715 static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
716 struct tcf_pkt_info *info)
717 {
718 int r;
719 struct meta_match *meta = (struct meta_match *) m->data;
720 struct meta_obj l_value, r_value;
721
722 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
723 meta_get(skb, info, &meta->rvalue, &r_value) < 0)
724 return 0;
725
726 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
727
728 switch (meta->lvalue.hdr.op) {
729 case TCF_EM_OPND_EQ:
730 return !r;
731 case TCF_EM_OPND_LT:
732 return r < 0;
733 case TCF_EM_OPND_GT:
734 return r > 0;
735 }
736
737 return 0;
738 }
739
740 static void meta_delete(struct meta_match *meta)
741 {
742 if (meta) {
743 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
744
745 if (ops && ops->destroy) {
746 ops->destroy(&meta->lvalue);
747 ops->destroy(&meta->rvalue);
748 }
749 }
750
751 kfree(meta);
752 }
753
754 static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla)
755 {
756 if (nla) {
757 if (nla_len(nla) == 0)
758 return -EINVAL;
759
760 return meta_type_ops(dst)->change(dst, nla);
761 }
762
763 return 0;
764 }
765
766 static inline int meta_is_supported(struct meta_value *val)
767 {
768 return (!meta_id(val) || meta_ops(val)->get);
769 }
770
771 static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = {
772 [TCA_EM_META_HDR] = { .len = sizeof(struct tcf_meta_hdr) },
773 };
774
775 static int em_meta_change(struct tcf_proto *tp, void *data, int len,
776 struct tcf_ematch *m)
777 {
778 int err;
779 struct nlattr *tb[TCA_EM_META_MAX + 1];
780 struct tcf_meta_hdr *hdr;
781 struct meta_match *meta = NULL;
782
783 err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy);
784 if (err < 0)
785 goto errout;
786
787 err = -EINVAL;
788 if (tb[TCA_EM_META_HDR] == NULL)
789 goto errout;
790 hdr = nla_data(tb[TCA_EM_META_HDR]);
791
792 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
793 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
794 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
795 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
796 goto errout;
797
798 meta = kzalloc(sizeof(*meta), GFP_KERNEL);
799 if (meta == NULL)
800 goto errout;
801
802 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
803 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
804
805 if (!meta_is_supported(&meta->lvalue) ||
806 !meta_is_supported(&meta->rvalue)) {
807 err = -EOPNOTSUPP;
808 goto errout;
809 }
810
811 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 ||
812 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0)
813 goto errout;
814
815 m->datalen = sizeof(*meta);
816 m->data = (unsigned long) meta;
817
818 err = 0;
819 errout:
820 if (err && meta)
821 meta_delete(meta);
822 return err;
823 }
824
825 static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
826 {
827 if (m)
828 meta_delete((struct meta_match *) m->data);
829 }
830
831 static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
832 {
833 struct meta_match *meta = (struct meta_match *) em->data;
834 struct tcf_meta_hdr hdr;
835 struct meta_type_ops *ops;
836
837 memset(&hdr, 0, sizeof(hdr));
838 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
839 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
840
841 NLA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr);
842
843 ops = meta_type_ops(&meta->lvalue);
844 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 ||
845 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0)
846 goto nla_put_failure;
847
848 return 0;
849
850 nla_put_failure:
851 return -1;
852 }
853
854 static struct tcf_ematch_ops em_meta_ops = {
855 .kind = TCF_EM_META,
856 .change = em_meta_change,
857 .match = em_meta_match,
858 .destroy = em_meta_destroy,
859 .dump = em_meta_dump,
860 .owner = THIS_MODULE,
861 .link = LIST_HEAD_INIT(em_meta_ops.link)
862 };
863
864 static int __init init_em_meta(void)
865 {
866 return tcf_em_register(&em_meta_ops);
867 }
868
869 static void __exit exit_em_meta(void)
870 {
871 tcf_em_unregister(&em_meta_ops);
872 }
873
874 MODULE_LICENSE("GPL");
875
876 module_init(init_em_meta);
877 module_exit(exit_em_meta);
878
879 MODULE_ALIAS_TCF_EMATCH(TCF_EM_META);
linux-next