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