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