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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/em_meta.c Metadata ematch
4 *
5 * Authors: Thomas Graf <tgraf@suug.ch>
6 *
7 * ==========================================================================
8 *
9 * The metadata ematch compares two meta objects where each object
10 * represents either a meta value stored in the kernel or a static
11 * value provided by userspace. The objects are not provided by
12 * userspace itself but rather a definition providing the information
13 * to build them. Every object is of a certain type which must be
14 * equal to the object it is being compared to.
15 *
16 * The definition of a objects conists of the type (meta type), a
17 * identifier (meta id) and additional type specific information.
18 * The meta id is either TCF_META_TYPE_VALUE for values provided by
19 * userspace or a index to the meta operations table consisting of
20 * function pointers to type specific meta data collectors returning
21 * the value of the requested meta value.
22 *
23 * lvalue rvalue
24 * +-----------+ +-----------+
25 * | type: INT | | type: INT |
26 * def | id: DEV | | id: VALUE |
27 * | data: | | data: 3 |
28 * +-----------+ +-----------+
29 * | |
30 * ---> meta_ops[INT][DEV](...) |
31 * | |
32 * ----------- |
33 * V V
34 * +-----------+ +-----------+
35 * | type: INT | | type: INT |
36 * obj | id: DEV | | id: VALUE |
37 * | data: 2 |<--data got filled out | data: 3 |
38 * +-----------+ +-----------+
39 * | |
40 * --------------> 2 equals 3 <--------------
41 *
42 * This is a simplified schema, the complexity varies depending
43 * on the meta type. Obviously, the length of the data must also
44 * be provided for non-numeric types.
45 *
46 * Additionally, type dependent modifiers such as shift operators
47 * or mask may be applied to extend the functionaliy. As of now,
48 * the variable length type supports shifting the byte string to
49 * the right, eating up any number of octets and thus supporting
50 * wildcard interface name comparisons such as "ppp%" matching
51 * ppp0..9.
52 *
53 * NOTE: Certain meta values depend on other subsystems and are
54 * only available if that subsystem is enabled in the kernel.
55 */
56
57#include <linux/slab.h>
58#include <linux/module.h>
59#include <linux/types.h>
60#include <linux/kernel.h>
61#include <linux/sched.h>
62#include <linux/sched/loadavg.h>
63#include <linux/string.h>
64#include <linux/skbuff.h>
65#include <linux/random.h>
66#include <linux/if_vlan.h>
67#include <linux/tc_ematch/tc_em_meta.h>
68#include <net/dst.h>
69#include <net/route.h>
70#include <net/pkt_cls.h>
71#include <net/sock.h>
72
73struct meta_obj {
74 unsigned long value;
75 unsigned int len;
76};
77
78struct meta_value {
79 struct tcf_meta_val hdr;
80 unsigned long val;
81 unsigned int len;
82};
83
84struct meta_match {
85 struct meta_value lvalue;
86 struct meta_value rvalue;
87};
88
89static inline int meta_id(struct meta_value *v)
90{
91 return TCF_META_ID(v->hdr.kind);
92}
93
94static inline int meta_type(struct meta_value *v)
95{
96 return TCF_META_TYPE(v->hdr.kind);
97}
98
99#define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \
100 struct tcf_pkt_info *info, struct meta_value *v, \
101 struct meta_obj *dst, int *err)
102
103/**************************************************************************
104 * System status & misc
105 **************************************************************************/
106
107META_COLLECTOR(int_random)
108{
109 get_random_bytes(&dst->value, sizeof(dst->value));
110}
111
112static inline unsigned long fixed_loadavg(int load)
113{
114 int rnd_load = load + (FIXED_1/200);
115 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT;
116
117 return ((rnd_load >> FSHIFT) * 100) + rnd_frac;
118}
119
120META_COLLECTOR(int_loadavg_0)
121{
122 dst->value = fixed_loadavg(avenrun[0]);
123}
124
125META_COLLECTOR(int_loadavg_1)
126{
127 dst->value = fixed_loadavg(avenrun[1]);
128}
129
130META_COLLECTOR(int_loadavg_2)
131{
132 dst->value = fixed_loadavg(avenrun[2]);
133}
134
135/**************************************************************************
136 * Device names & indices
137 **************************************************************************/
138
139static inline int int_dev(struct net_device *dev, struct meta_obj *dst)
140{
141 if (unlikely(dev == NULL))
142 return -1;
143
144 dst->value = dev->ifindex;
145 return 0;
146}
147
148static inline int var_dev(struct net_device *dev, struct meta_obj *dst)
149{
150 if (unlikely(dev == NULL))
151 return -1;
152
153 dst->value = (unsigned long) dev->name;
154 dst->len = strlen(dev->name);
155 return 0;
156}
157
158META_COLLECTOR(int_dev)
159{
160 *err = int_dev(skb->dev, dst);
161}
162
163META_COLLECTOR(var_dev)
164{
165 *err = var_dev(skb->dev, dst);
166}
167
168/**************************************************************************
169 * vlan tag
170 **************************************************************************/
171
172META_COLLECTOR(int_vlan_tag)
173{
174 unsigned short tag;
175
176 if (skb_vlan_tag_present(skb))
177 dst->value = skb_vlan_tag_get(skb);
178 else if (!__vlan_get_tag(skb, &tag))
179 dst->value = tag;
180 else
181 *err = -1;
182}
183
184
185
186/**************************************************************************
187 * skb attributes
188 **************************************************************************/
189
190META_COLLECTOR(int_priority)
191{
192 dst->value = skb->priority;
193}
194
195META_COLLECTOR(int_protocol)
196{
197 /* Let userspace take care of the byte ordering */
198 dst->value = tc_skb_protocol(skb);
199}
200
201META_COLLECTOR(int_pkttype)
202{
203 dst->value = skb->pkt_type;
204}
205
206META_COLLECTOR(int_pktlen)
207{
208 dst->value = skb->len;
209}
210
211META_COLLECTOR(int_datalen)
212{
213 dst->value = skb->data_len;
214}
215
216META_COLLECTOR(int_maclen)
217{
218 dst->value = skb->mac_len;
219}
220
221META_COLLECTOR(int_rxhash)
222{
223 dst->value = skb_get_hash(skb);
224}
225
226/**************************************************************************
227 * Netfilter
228 **************************************************************************/
229
230META_COLLECTOR(int_mark)
231{
232 dst->value = skb->mark;
233}
234
235/**************************************************************************
236 * Traffic Control
237 **************************************************************************/
238
239META_COLLECTOR(int_tcindex)
240{
241 dst->value = skb->tc_index;
242}
243
244/**************************************************************************
245 * Routing
246 **************************************************************************/
247
248META_COLLECTOR(int_rtclassid)
249{
250 if (unlikely(skb_dst(skb) == NULL))
251 *err = -1;
252 else
253#ifdef CONFIG_IP_ROUTE_CLASSID
254 dst->value = skb_dst(skb)->tclassid;
255#else
256 dst->value = 0;
257#endif
258}
259
260META_COLLECTOR(int_rtiif)
261{
262 if (unlikely(skb_rtable(skb) == NULL))
263 *err = -1;
264 else
265 dst->value = inet_iif(skb);
266}
267
268/**************************************************************************
269 * Socket Attributes
270 **************************************************************************/
271
272#define skip_nonlocal(skb) \
273 (unlikely(skb->sk == NULL))
274
275META_COLLECTOR(int_sk_family)
276{
277 if (skip_nonlocal(skb)) {
278 *err = -1;
279 return;
280 }
281 dst->value = skb->sk->sk_family;
282}
283
284META_COLLECTOR(int_sk_state)
285{
286 if (skip_nonlocal(skb)) {
287 *err = -1;
288 return;
289 }
290 dst->value = skb->sk->sk_state;
291}
292
293META_COLLECTOR(int_sk_reuse)
294{
295 if (skip_nonlocal(skb)) {
296 *err = -1;
297 return;
298 }
299 dst->value = skb->sk->sk_reuse;
300}
301
302META_COLLECTOR(int_sk_bound_if)
303{
304 if (skip_nonlocal(skb)) {
305 *err = -1;
306 return;
307 }
308 /* No error if bound_dev_if is 0, legal userspace check */
309 dst->value = skb->sk->sk_bound_dev_if;
310}
311
312META_COLLECTOR(var_sk_bound_if)
313{
314 if (skip_nonlocal(skb)) {
315 *err = -1;
316 return;
317 }
318
319 if (skb->sk->sk_bound_dev_if == 0) {
320 dst->value = (unsigned long) "any";
321 dst->len = 3;
322 } else {
323 struct net_device *dev;
324
325 rcu_read_lock();
326 dev = dev_get_by_index_rcu(sock_net(skb->sk),
327 skb->sk->sk_bound_dev_if);
328 *err = var_dev(dev, dst);
329 rcu_read_unlock();
330 }
331}
332
333META_COLLECTOR(int_sk_refcnt)
334{
335 if (skip_nonlocal(skb)) {
336 *err = -1;
337 return;
338 }
339 dst->value = refcount_read(&skb->sk->sk_refcnt);
340}
341
342META_COLLECTOR(int_sk_rcvbuf)
343{
344 const struct sock *sk = skb_to_full_sk(skb);
345
346 if (!sk) {
347 *err = -1;
348 return;
349 }
350 dst->value = sk->sk_rcvbuf;
351}
352
353META_COLLECTOR(int_sk_shutdown)
354{
355 const struct sock *sk = skb_to_full_sk(skb);
356
357 if (!sk) {
358 *err = -1;
359 return;
360 }
361 dst->value = sk->sk_shutdown;
362}
363
364META_COLLECTOR(int_sk_proto)
365{
366 const struct sock *sk = skb_to_full_sk(skb);
367
368 if (!sk) {
369 *err = -1;
370 return;
371 }
372 dst->value = sk->sk_protocol;
373}
374
375META_COLLECTOR(int_sk_type)
376{
377 const struct sock *sk = skb_to_full_sk(skb);
378
379 if (!sk) {
380 *err = -1;
381 return;
382 }
383 dst->value = sk->sk_type;
384}
385
386META_COLLECTOR(int_sk_rmem_alloc)
387{
388 const struct sock *sk = skb_to_full_sk(skb);
389
390 if (!sk) {
391 *err = -1;
392 return;
393 }
394 dst->value = sk_rmem_alloc_get(sk);
395}
396
397META_COLLECTOR(int_sk_wmem_alloc)
398{
399 const struct sock *sk = skb_to_full_sk(skb);
400
401 if (!sk) {
402 *err = -1;
403 return;
404 }
405 dst->value = sk_wmem_alloc_get(sk);
406}
407
408META_COLLECTOR(int_sk_omem_alloc)
409{
410 const struct sock *sk = skb_to_full_sk(skb);
411
412 if (!sk) {
413 *err = -1;
414 return;
415 }
416 dst->value = atomic_read(&sk->sk_omem_alloc);
417}
418
419META_COLLECTOR(int_sk_rcv_qlen)
420{
421 const struct sock *sk = skb_to_full_sk(skb);
422
423 if (!sk) {
424 *err = -1;
425 return;
426 }
427 dst->value = sk->sk_receive_queue.qlen;
428}
429
430META_COLLECTOR(int_sk_snd_qlen)
431{
432 const struct sock *sk = skb_to_full_sk(skb);
433
434 if (!sk) {
435 *err = -1;
436 return;
437 }
438 dst->value = sk->sk_write_queue.qlen;
439}
440
441META_COLLECTOR(int_sk_wmem_queued)
442{
443 const struct sock *sk = skb_to_full_sk(skb);
444
445 if (!sk) {
446 *err = -1;
447 return;
448 }
449 dst->value = READ_ONCE(sk->sk_wmem_queued);
450}
451
452META_COLLECTOR(int_sk_fwd_alloc)
453{
454 const struct sock *sk = skb_to_full_sk(skb);
455
456 if (!sk) {
457 *err = -1;
458 return;
459 }
460 dst->value = sk->sk_forward_alloc;
461}
462
463META_COLLECTOR(int_sk_sndbuf)
464{
465 const struct sock *sk = skb_to_full_sk(skb);
466
467 if (!sk) {
468 *err = -1;
469 return;
470 }
471 dst->value = sk->sk_sndbuf;
472}
473
474META_COLLECTOR(int_sk_alloc)
475{
476 const struct sock *sk = skb_to_full_sk(skb);
477
478 if (!sk) {
479 *err = -1;
480 return;
481 }
482 dst->value = (__force int) sk->sk_allocation;
483}
484
485META_COLLECTOR(int_sk_hash)
486{
487 if (skip_nonlocal(skb)) {
488 *err = -1;
489 return;
490 }
491 dst->value = skb->sk->sk_hash;
492}
493
494META_COLLECTOR(int_sk_lingertime)
495{
496 const struct sock *sk = skb_to_full_sk(skb);
497
498 if (!sk) {
499 *err = -1;
500 return;
501 }
502 dst->value = sk->sk_lingertime / HZ;
503}
504
505META_COLLECTOR(int_sk_err_qlen)
506{
507 const struct sock *sk = skb_to_full_sk(skb);
508
509 if (!sk) {
510 *err = -1;
511 return;
512 }
513 dst->value = sk->sk_error_queue.qlen;
514}
515
516META_COLLECTOR(int_sk_ack_bl)
517{
518 const struct sock *sk = skb_to_full_sk(skb);
519
520 if (!sk) {
521 *err = -1;
522 return;
523 }
524 dst->value = sk->sk_ack_backlog;
525}
526
527META_COLLECTOR(int_sk_max_ack_bl)
528{
529 const struct sock *sk = skb_to_full_sk(skb);
530
531 if (!sk) {
532 *err = -1;
533 return;
534 }
535 dst->value = sk->sk_max_ack_backlog;
536}
537
538META_COLLECTOR(int_sk_prio)
539{
540 const struct sock *sk = skb_to_full_sk(skb);
541
542 if (!sk) {
543 *err = -1;
544 return;
545 }
546 dst->value = sk->sk_priority;
547}
548
549META_COLLECTOR(int_sk_rcvlowat)
550{
551 const struct sock *sk = skb_to_full_sk(skb);
552
553 if (!sk) {
554 *err = -1;
555 return;
556 }
557 dst->value = READ_ONCE(sk->sk_rcvlowat);
558}
559
560META_COLLECTOR(int_sk_rcvtimeo)
561{
562 const struct sock *sk = skb_to_full_sk(skb);
563
564 if (!sk) {
565 *err = -1;
566 return;
567 }
568 dst->value = sk->sk_rcvtimeo / HZ;
569}
570
571META_COLLECTOR(int_sk_sndtimeo)
572{
573 const struct sock *sk = skb_to_full_sk(skb);
574
575 if (!sk) {
576 *err = -1;
577 return;
578 }
579 dst->value = sk->sk_sndtimeo / HZ;
580}
581
582META_COLLECTOR(int_sk_sendmsg_off)
583{
584 const struct sock *sk = skb_to_full_sk(skb);
585
586 if (!sk) {
587 *err = -1;
588 return;
589 }
590 dst->value = sk->sk_frag.offset;
591}
592
593META_COLLECTOR(int_sk_write_pend)
594{
595 const struct sock *sk = skb_to_full_sk(skb);
596
597 if (!sk) {
598 *err = -1;
599 return;
600 }
601 dst->value = sk->sk_write_pending;
602}
603
604/**************************************************************************
605 * Meta value collectors assignment table
606 **************************************************************************/
607
608struct meta_ops {
609 void (*get)(struct sk_buff *, struct tcf_pkt_info *,
610 struct meta_value *, struct meta_obj *, int *);
611};
612
613#define META_ID(name) TCF_META_ID_##name
614#define META_FUNC(name) { .get = meta_##name }
615
616/* Meta value operations table listing all meta value collectors and
617 * assigns them to a type and meta id. */
618static struct meta_ops __meta_ops[TCF_META_TYPE_MAX + 1][TCF_META_ID_MAX + 1] = {
619 [TCF_META_TYPE_VAR] = {
620 [META_ID(DEV)] = META_FUNC(var_dev),
621 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if),
622 },
623 [TCF_META_TYPE_INT] = {
624 [META_ID(RANDOM)] = META_FUNC(int_random),
625 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0),
626 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1),
627 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2),
628 [META_ID(DEV)] = META_FUNC(int_dev),
629 [META_ID(PRIORITY)] = META_FUNC(int_priority),
630 [META_ID(PROTOCOL)] = META_FUNC(int_protocol),
631 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype),
632 [META_ID(PKTLEN)] = META_FUNC(int_pktlen),
633 [META_ID(DATALEN)] = META_FUNC(int_datalen),
634 [META_ID(MACLEN)] = META_FUNC(int_maclen),
635 [META_ID(NFMARK)] = META_FUNC(int_mark),
636 [META_ID(TCINDEX)] = META_FUNC(int_tcindex),
637 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid),
638 [META_ID(RTIIF)] = META_FUNC(int_rtiif),
639 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family),
640 [META_ID(SK_STATE)] = META_FUNC(int_sk_state),
641 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse),
642 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if),
643 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt),
644 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf),
645 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf),
646 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown),
647 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto),
648 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type),
649 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc),
650 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc),
651 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc),
652 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued),
653 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen),
654 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen),
655 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen),
656 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc),
657 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc),
658 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash),
659 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime),
660 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl),
661 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl),
662 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio),
663 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat),
664 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo),
665 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo),
666 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off),
667 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend),
668 [META_ID(VLAN_TAG)] = META_FUNC(int_vlan_tag),
669 [META_ID(RXHASH)] = META_FUNC(int_rxhash),
670 }
671};
672
673static inline struct meta_ops *meta_ops(struct meta_value *val)
674{
675 return &__meta_ops[meta_type(val)][meta_id(val)];
676}
677
678/**************************************************************************
679 * Type specific operations for TCF_META_TYPE_VAR
680 **************************************************************************/
681
682static int meta_var_compare(struct meta_obj *a, struct meta_obj *b)
683{
684 int r = a->len - b->len;
685
686 if (r == 0)
687 r = memcmp((void *) a->value, (void *) b->value, a->len);
688
689 return r;
690}
691
692static int meta_var_change(struct meta_value *dst, struct nlattr *nla)
693{
694 int len = nla_len(nla);
695
696 dst->val = (unsigned long)kmemdup(nla_data(nla), len, GFP_KERNEL);
697 if (dst->val == 0UL)
698 return -ENOMEM;
699 dst->len = len;
700 return 0;
701}
702
703static void meta_var_destroy(struct meta_value *v)
704{
705 kfree((void *) v->val);
706}
707
708static void meta_var_apply_extras(struct meta_value *v,
709 struct meta_obj *dst)
710{
711 int shift = v->hdr.shift;
712
713 if (shift && shift < dst->len)
714 dst->len -= shift;
715}
716
717static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
718{
719 if (v->val && v->len &&
720 nla_put(skb, tlv, v->len, (void *) v->val))
721 goto nla_put_failure;
722 return 0;
723
724nla_put_failure:
725 return -1;
726}
727
728/**************************************************************************
729 * Type specific operations for TCF_META_TYPE_INT
730 **************************************************************************/
731
732static int meta_int_compare(struct meta_obj *a, struct meta_obj *b)
733{
734 /* Let gcc optimize it, the unlikely is not really based on
735 * some numbers but jump free code for mismatches seems
736 * more logical. */
737 if (unlikely(a->value == b->value))
738 return 0;
739 else if (a->value < b->value)
740 return -1;
741 else
742 return 1;
743}
744
745static int meta_int_change(struct meta_value *dst, struct nlattr *nla)
746{
747 if (nla_len(nla) >= sizeof(unsigned long)) {
748 dst->val = *(unsigned long *) nla_data(nla);
749 dst->len = sizeof(unsigned long);
750 } else if (nla_len(nla) == sizeof(u32)) {
751 dst->val = nla_get_u32(nla);
752 dst->len = sizeof(u32);
753 } else
754 return -EINVAL;
755
756 return 0;
757}
758
759static void meta_int_apply_extras(struct meta_value *v,
760 struct meta_obj *dst)
761{
762 if (v->hdr.shift)
763 dst->value >>= v->hdr.shift;
764
765 if (v->val)
766 dst->value &= v->val;
767}
768
769static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
770{
771 if (v->len == sizeof(unsigned long)) {
772 if (nla_put(skb, tlv, sizeof(unsigned long), &v->val))
773 goto nla_put_failure;
774 } else if (v->len == sizeof(u32)) {
775 if (nla_put_u32(skb, tlv, v->val))
776 goto nla_put_failure;
777 }
778
779 return 0;
780
781nla_put_failure:
782 return -1;
783}
784
785/**************************************************************************
786 * Type specific operations table
787 **************************************************************************/
788
789struct meta_type_ops {
790 void (*destroy)(struct meta_value *);
791 int (*compare)(struct meta_obj *, struct meta_obj *);
792 int (*change)(struct meta_value *, struct nlattr *);
793 void (*apply_extras)(struct meta_value *, struct meta_obj *);
794 int (*dump)(struct sk_buff *, struct meta_value *, int);
795};
796
797static const struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX + 1] = {
798 [TCF_META_TYPE_VAR] = {
799 .destroy = meta_var_destroy,
800 .compare = meta_var_compare,
801 .change = meta_var_change,
802 .apply_extras = meta_var_apply_extras,
803 .dump = meta_var_dump
804 },
805 [TCF_META_TYPE_INT] = {
806 .compare = meta_int_compare,
807 .change = meta_int_change,
808 .apply_extras = meta_int_apply_extras,
809 .dump = meta_int_dump
810 }
811};
812
813static inline const struct meta_type_ops *meta_type_ops(struct meta_value *v)
814{
815 return &__meta_type_ops[meta_type(v)];
816}
817
818/**************************************************************************
819 * Core
820 **************************************************************************/
821
822static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
823 struct meta_value *v, struct meta_obj *dst)
824{
825 int err = 0;
826
827 if (meta_id(v) == TCF_META_ID_VALUE) {
828 dst->value = v->val;
829 dst->len = v->len;
830 return 0;
831 }
832
833 meta_ops(v)->get(skb, info, v, dst, &err);
834 if (err < 0)
835 return err;
836
837 if (meta_type_ops(v)->apply_extras)
838 meta_type_ops(v)->apply_extras(v, dst);
839
840 return 0;
841}
842
843static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
844 struct tcf_pkt_info *info)
845{
846 int r;
847 struct meta_match *meta = (struct meta_match *) m->data;
848 struct meta_obj l_value, r_value;
849
850 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
851 meta_get(skb, info, &meta->rvalue, &r_value) < 0)
852 return 0;
853
854 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
855
856 switch (meta->lvalue.hdr.op) {
857 case TCF_EM_OPND_EQ:
858 return !r;
859 case TCF_EM_OPND_LT:
860 return r < 0;
861 case TCF_EM_OPND_GT:
862 return r > 0;
863 }
864
865 return 0;
866}
867
868static void meta_delete(struct meta_match *meta)
869{
870 if (meta) {
871 const struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
872
873 if (ops && ops->destroy) {
874 ops->destroy(&meta->lvalue);
875 ops->destroy(&meta->rvalue);
876 }
877 }
878
879 kfree(meta);
880}
881
882static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla)
883{
884 if (nla) {
885 if (nla_len(nla) == 0)
886 return -EINVAL;
887
888 return meta_type_ops(dst)->change(dst, nla);
889 }
890
891 return 0;
892}
893
894static inline int meta_is_supported(struct meta_value *val)
895{
896 return !meta_id(val) || meta_ops(val)->get;
897}
898
899static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = {
900 [TCA_EM_META_HDR] = { .len = sizeof(struct tcf_meta_hdr) },
901};
902
903static int em_meta_change(struct net *net, void *data, int len,
904 struct tcf_ematch *m)
905{
906 int err;
907 struct nlattr *tb[TCA_EM_META_MAX + 1];
908 struct tcf_meta_hdr *hdr;
909 struct meta_match *meta = NULL;
910
911 err = nla_parse_deprecated(tb, TCA_EM_META_MAX, data, len,
912 meta_policy, NULL);
913 if (err < 0)
914 goto errout;
915
916 err = -EINVAL;
917 if (tb[TCA_EM_META_HDR] == NULL)
918 goto errout;
919 hdr = nla_data(tb[TCA_EM_META_HDR]);
920
921 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
922 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
923 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
924 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
925 goto errout;
926
927 meta = kzalloc(sizeof(*meta), GFP_KERNEL);
928 if (meta == NULL) {
929 err = -ENOMEM;
930 goto errout;
931 }
932
933 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
934 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
935
936 if (!meta_is_supported(&meta->lvalue) ||
937 !meta_is_supported(&meta->rvalue)) {
938 err = -EOPNOTSUPP;
939 goto errout;
940 }
941
942 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 ||
943 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0)
944 goto errout;
945
946 m->datalen = sizeof(*meta);
947 m->data = (unsigned long) meta;
948
949 err = 0;
950errout:
951 if (err && meta)
952 meta_delete(meta);
953 return err;
954}
955
956static void em_meta_destroy(struct tcf_ematch *m)
957{
958 if (m)
959 meta_delete((struct meta_match *) m->data);
960}
961
962static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
963{
964 struct meta_match *meta = (struct meta_match *) em->data;
965 struct tcf_meta_hdr hdr;
966 const struct meta_type_ops *ops;
967
968 memset(&hdr, 0, sizeof(hdr));
969 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
970 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
971
972 if (nla_put(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr))
973 goto nla_put_failure;
974
975 ops = meta_type_ops(&meta->lvalue);
976 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 ||
977 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0)
978 goto nla_put_failure;
979
980 return 0;
981
982nla_put_failure:
983 return -1;
984}
985
986static struct tcf_ematch_ops em_meta_ops = {
987 .kind = TCF_EM_META,
988 .change = em_meta_change,
989 .match = em_meta_match,
990 .destroy = em_meta_destroy,
991 .dump = em_meta_dump,
992 .owner = THIS_MODULE,
993 .link = LIST_HEAD_INIT(em_meta_ops.link)
994};
995
996static int __init init_em_meta(void)
997{
998 return tcf_em_register(&em_meta_ops);
999}
1000
1001static void __exit exit_em_meta(void)
1002{
1003 tcf_em_unregister(&em_meta_ops);
1004}
1005
1006MODULE_LICENSE("GPL");
1007
1008module_init(init_em_meta);
1009module_exit(exit_em_meta);
1010
1011MODULE_ALIAS_TCF_EMATCH(TCF_EM_META);
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 * Additionally, type dependent 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
76struct meta_obj {
77 unsigned long value;
78 unsigned int len;
79};
80
81struct meta_value {
82 struct tcf_meta_val hdr;
83 unsigned long val;
84 unsigned int len;
85};
86
87struct meta_match {
88 struct meta_value lvalue;
89 struct meta_value rvalue;
90};
91
92static inline int meta_id(struct meta_value *v)
93{
94 return TCF_META_ID(v->hdr.kind);
95}
96
97static inline int meta_type(struct meta_value *v)
98{
99 return TCF_META_TYPE(v->hdr.kind);
100}
101
102#define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \
103 struct tcf_pkt_info *info, struct meta_value *v, \
104 struct meta_obj *dst, int *err)
105
106/**************************************************************************
107 * System status & misc
108 **************************************************************************/
109
110META_COLLECTOR(int_random)
111{
112 get_random_bytes(&dst->value, sizeof(dst->value));
113}
114
115static inline unsigned long fixed_loadavg(int load)
116{
117 int rnd_load = load + (FIXED_1/200);
118 int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT;
119
120 return ((rnd_load >> FSHIFT) * 100) + rnd_frac;
121}
122
123META_COLLECTOR(int_loadavg_0)
124{
125 dst->value = fixed_loadavg(avenrun[0]);
126}
127
128META_COLLECTOR(int_loadavg_1)
129{
130 dst->value = fixed_loadavg(avenrun[1]);
131}
132
133META_COLLECTOR(int_loadavg_2)
134{
135 dst->value = fixed_loadavg(avenrun[2]);
136}
137
138/**************************************************************************
139 * Device names & indices
140 **************************************************************************/
141
142static inline int int_dev(struct net_device *dev, struct meta_obj *dst)
143{
144 if (unlikely(dev == NULL))
145 return -1;
146
147 dst->value = dev->ifindex;
148 return 0;
149}
150
151static inline int var_dev(struct net_device *dev, struct meta_obj *dst)
152{
153 if (unlikely(dev == NULL))
154 return -1;
155
156 dst->value = (unsigned long) dev->name;
157 dst->len = strlen(dev->name);
158 return 0;
159}
160
161META_COLLECTOR(int_dev)
162{
163 *err = int_dev(skb->dev, dst);
164}
165
166META_COLLECTOR(var_dev)
167{
168 *err = var_dev(skb->dev, dst);
169}
170
171/**************************************************************************
172 * vlan tag
173 **************************************************************************/
174
175META_COLLECTOR(int_vlan_tag)
176{
177 unsigned short tag;
178
179 tag = vlan_tx_tag_get(skb);
180 if (!tag && __vlan_get_tag(skb, &tag))
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
223META_COLLECTOR(int_rxhash)
224{
225 dst->value = skb_get_rxhash(skb);
226}
227
228/**************************************************************************
229 * Netfilter
230 **************************************************************************/
231
232META_COLLECTOR(int_mark)
233{
234 dst->value = skb->mark;
235}
236
237/**************************************************************************
238 * Traffic Control
239 **************************************************************************/
240
241META_COLLECTOR(int_tcindex)
242{
243 dst->value = skb->tc_index;
244}
245
246/**************************************************************************
247 * Routing
248 **************************************************************************/
249
250META_COLLECTOR(int_rtclassid)
251{
252 if (unlikely(skb_dst(skb) == NULL))
253 *err = -1;
254 else
255#ifdef CONFIG_IP_ROUTE_CLASSID
256 dst->value = skb_dst(skb)->tclassid;
257#else
258 dst->value = 0;
259#endif
260}
261
262META_COLLECTOR(int_rtiif)
263{
264 if (unlikely(skb_rtable(skb) == NULL))
265 *err = -1;
266 else
267 dst->value = skb_rtable(skb)->rt_iif;
268}
269
270/**************************************************************************
271 * Socket Attributes
272 **************************************************************************/
273
274#define SKIP_NONLOCAL(skb) \
275 if (unlikely(skb->sk == NULL)) { \
276 *err = -1; \
277 return; \
278 }
279
280META_COLLECTOR(int_sk_family)
281{
282 SKIP_NONLOCAL(skb);
283 dst->value = skb->sk->sk_family;
284}
285
286META_COLLECTOR(int_sk_state)
287{
288 SKIP_NONLOCAL(skb);
289 dst->value = skb->sk->sk_state;
290}
291
292META_COLLECTOR(int_sk_reuse)
293{
294 SKIP_NONLOCAL(skb);
295 dst->value = skb->sk->sk_reuse;
296}
297
298META_COLLECTOR(int_sk_bound_if)
299{
300 SKIP_NONLOCAL(skb);
301 /* No error if bound_dev_if is 0, legal userspace check */
302 dst->value = skb->sk->sk_bound_dev_if;
303}
304
305META_COLLECTOR(var_sk_bound_if)
306{
307 SKIP_NONLOCAL(skb);
308
309 if (skb->sk->sk_bound_dev_if == 0) {
310 dst->value = (unsigned long) "any";
311 dst->len = 3;
312 } else {
313 struct net_device *dev;
314
315 rcu_read_lock();
316 dev = dev_get_by_index_rcu(sock_net(skb->sk),
317 skb->sk->sk_bound_dev_if);
318 *err = var_dev(dev, dst);
319 rcu_read_unlock();
320 }
321}
322
323META_COLLECTOR(int_sk_refcnt)
324{
325 SKIP_NONLOCAL(skb);
326 dst->value = atomic_read(&skb->sk->sk_refcnt);
327}
328
329META_COLLECTOR(int_sk_rcvbuf)
330{
331 SKIP_NONLOCAL(skb);
332 dst->value = skb->sk->sk_rcvbuf;
333}
334
335META_COLLECTOR(int_sk_shutdown)
336{
337 SKIP_NONLOCAL(skb);
338 dst->value = skb->sk->sk_shutdown;
339}
340
341META_COLLECTOR(int_sk_proto)
342{
343 SKIP_NONLOCAL(skb);
344 dst->value = skb->sk->sk_protocol;
345}
346
347META_COLLECTOR(int_sk_type)
348{
349 SKIP_NONLOCAL(skb);
350 dst->value = skb->sk->sk_type;
351}
352
353META_COLLECTOR(int_sk_rmem_alloc)
354{
355 SKIP_NONLOCAL(skb);
356 dst->value = sk_rmem_alloc_get(skb->sk);
357}
358
359META_COLLECTOR(int_sk_wmem_alloc)
360{
361 SKIP_NONLOCAL(skb);
362 dst->value = sk_wmem_alloc_get(skb->sk);
363}
364
365META_COLLECTOR(int_sk_omem_alloc)
366{
367 SKIP_NONLOCAL(skb);
368 dst->value = atomic_read(&skb->sk->sk_omem_alloc);
369}
370
371META_COLLECTOR(int_sk_rcv_qlen)
372{
373 SKIP_NONLOCAL(skb);
374 dst->value = skb->sk->sk_receive_queue.qlen;
375}
376
377META_COLLECTOR(int_sk_snd_qlen)
378{
379 SKIP_NONLOCAL(skb);
380 dst->value = skb->sk->sk_write_queue.qlen;
381}
382
383META_COLLECTOR(int_sk_wmem_queued)
384{
385 SKIP_NONLOCAL(skb);
386 dst->value = skb->sk->sk_wmem_queued;
387}
388
389META_COLLECTOR(int_sk_fwd_alloc)
390{
391 SKIP_NONLOCAL(skb);
392 dst->value = skb->sk->sk_forward_alloc;
393}
394
395META_COLLECTOR(int_sk_sndbuf)
396{
397 SKIP_NONLOCAL(skb);
398 dst->value = skb->sk->sk_sndbuf;
399}
400
401META_COLLECTOR(int_sk_alloc)
402{
403 SKIP_NONLOCAL(skb);
404 dst->value = (__force int) skb->sk->sk_allocation;
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 void (*get)(struct sk_buff *, struct tcf_pkt_info *,
479 struct meta_value *, struct meta_obj *, int *);
480};
481
482#define META_ID(name) TCF_META_ID_##name
483#define META_FUNC(name) { .get = meta_##name }
484
485/* Meta value operations table listing all meta value collectors and
486 * assigns them to a type and meta id. */
487static struct meta_ops __meta_ops[TCF_META_TYPE_MAX + 1][TCF_META_ID_MAX + 1] = {
488 [TCF_META_TYPE_VAR] = {
489 [META_ID(DEV)] = META_FUNC(var_dev),
490 [META_ID(SK_BOUND_IF)] = META_FUNC(var_sk_bound_if),
491 },
492 [TCF_META_TYPE_INT] = {
493 [META_ID(RANDOM)] = META_FUNC(int_random),
494 [META_ID(LOADAVG_0)] = META_FUNC(int_loadavg_0),
495 [META_ID(LOADAVG_1)] = META_FUNC(int_loadavg_1),
496 [META_ID(LOADAVG_2)] = META_FUNC(int_loadavg_2),
497 [META_ID(DEV)] = META_FUNC(int_dev),
498 [META_ID(PRIORITY)] = META_FUNC(int_priority),
499 [META_ID(PROTOCOL)] = META_FUNC(int_protocol),
500 [META_ID(PKTTYPE)] = META_FUNC(int_pkttype),
501 [META_ID(PKTLEN)] = META_FUNC(int_pktlen),
502 [META_ID(DATALEN)] = META_FUNC(int_datalen),
503 [META_ID(MACLEN)] = META_FUNC(int_maclen),
504 [META_ID(NFMARK)] = META_FUNC(int_mark),
505 [META_ID(TCINDEX)] = META_FUNC(int_tcindex),
506 [META_ID(RTCLASSID)] = META_FUNC(int_rtclassid),
507 [META_ID(RTIIF)] = META_FUNC(int_rtiif),
508 [META_ID(SK_FAMILY)] = META_FUNC(int_sk_family),
509 [META_ID(SK_STATE)] = META_FUNC(int_sk_state),
510 [META_ID(SK_REUSE)] = META_FUNC(int_sk_reuse),
511 [META_ID(SK_BOUND_IF)] = META_FUNC(int_sk_bound_if),
512 [META_ID(SK_REFCNT)] = META_FUNC(int_sk_refcnt),
513 [META_ID(SK_RCVBUF)] = META_FUNC(int_sk_rcvbuf),
514 [META_ID(SK_SNDBUF)] = META_FUNC(int_sk_sndbuf),
515 [META_ID(SK_SHUTDOWN)] = META_FUNC(int_sk_shutdown),
516 [META_ID(SK_PROTO)] = META_FUNC(int_sk_proto),
517 [META_ID(SK_TYPE)] = META_FUNC(int_sk_type),
518 [META_ID(SK_RMEM_ALLOC)] = META_FUNC(int_sk_rmem_alloc),
519 [META_ID(SK_WMEM_ALLOC)] = META_FUNC(int_sk_wmem_alloc),
520 [META_ID(SK_OMEM_ALLOC)] = META_FUNC(int_sk_omem_alloc),
521 [META_ID(SK_WMEM_QUEUED)] = META_FUNC(int_sk_wmem_queued),
522 [META_ID(SK_RCV_QLEN)] = META_FUNC(int_sk_rcv_qlen),
523 [META_ID(SK_SND_QLEN)] = META_FUNC(int_sk_snd_qlen),
524 [META_ID(SK_ERR_QLEN)] = META_FUNC(int_sk_err_qlen),
525 [META_ID(SK_FORWARD_ALLOCS)] = META_FUNC(int_sk_fwd_alloc),
526 [META_ID(SK_ALLOCS)] = META_FUNC(int_sk_alloc),
527 [META_ID(SK_HASH)] = META_FUNC(int_sk_hash),
528 [META_ID(SK_LINGERTIME)] = META_FUNC(int_sk_lingertime),
529 [META_ID(SK_ACK_BACKLOG)] = META_FUNC(int_sk_ack_bl),
530 [META_ID(SK_MAX_ACK_BACKLOG)] = META_FUNC(int_sk_max_ack_bl),
531 [META_ID(SK_PRIO)] = META_FUNC(int_sk_prio),
532 [META_ID(SK_RCVLOWAT)] = META_FUNC(int_sk_rcvlowat),
533 [META_ID(SK_RCVTIMEO)] = META_FUNC(int_sk_rcvtimeo),
534 [META_ID(SK_SNDTIMEO)] = META_FUNC(int_sk_sndtimeo),
535 [META_ID(SK_SENDMSG_OFF)] = META_FUNC(int_sk_sendmsg_off),
536 [META_ID(SK_WRITE_PENDING)] = META_FUNC(int_sk_write_pend),
537 [META_ID(VLAN_TAG)] = META_FUNC(int_vlan_tag),
538 [META_ID(RXHASH)] = META_FUNC(int_rxhash),
539 }
540};
541
542static inline struct meta_ops *meta_ops(struct meta_value *val)
543{
544 return &__meta_ops[meta_type(val)][meta_id(val)];
545}
546
547/**************************************************************************
548 * Type specific operations for TCF_META_TYPE_VAR
549 **************************************************************************/
550
551static int meta_var_compare(struct meta_obj *a, struct meta_obj *b)
552{
553 int r = a->len - b->len;
554
555 if (r == 0)
556 r = memcmp((void *) a->value, (void *) b->value, a->len);
557
558 return r;
559}
560
561static int meta_var_change(struct meta_value *dst, struct nlattr *nla)
562{
563 int len = nla_len(nla);
564
565 dst->val = (unsigned long)kmemdup(nla_data(nla), len, GFP_KERNEL);
566 if (dst->val == 0UL)
567 return -ENOMEM;
568 dst->len = len;
569 return 0;
570}
571
572static void meta_var_destroy(struct meta_value *v)
573{
574 kfree((void *) v->val);
575}
576
577static void meta_var_apply_extras(struct meta_value *v,
578 struct meta_obj *dst)
579{
580 int shift = v->hdr.shift;
581
582 if (shift && shift < dst->len)
583 dst->len -= shift;
584}
585
586static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
587{
588 if (v->val && v->len)
589 NLA_PUT(skb, tlv, v->len, (void *) v->val);
590 return 0;
591
592nla_put_failure:
593 return -1;
594}
595
596/**************************************************************************
597 * Type specific operations for TCF_META_TYPE_INT
598 **************************************************************************/
599
600static int meta_int_compare(struct meta_obj *a, struct meta_obj *b)
601{
602 /* Let gcc optimize it, the unlikely is not really based on
603 * some numbers but jump free code for mismatches seems
604 * more logical. */
605 if (unlikely(a->value == b->value))
606 return 0;
607 else if (a->value < b->value)
608 return -1;
609 else
610 return 1;
611}
612
613static int meta_int_change(struct meta_value *dst, struct nlattr *nla)
614{
615 if (nla_len(nla) >= sizeof(unsigned long)) {
616 dst->val = *(unsigned long *) nla_data(nla);
617 dst->len = sizeof(unsigned long);
618 } else if (nla_len(nla) == sizeof(u32)) {
619 dst->val = nla_get_u32(nla);
620 dst->len = sizeof(u32);
621 } else
622 return -EINVAL;
623
624 return 0;
625}
626
627static void meta_int_apply_extras(struct meta_value *v,
628 struct meta_obj *dst)
629{
630 if (v->hdr.shift)
631 dst->value >>= v->hdr.shift;
632
633 if (v->val)
634 dst->value &= v->val;
635}
636
637static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
638{
639 if (v->len == sizeof(unsigned long))
640 NLA_PUT(skb, tlv, sizeof(unsigned long), &v->val);
641 else if (v->len == sizeof(u32))
642 NLA_PUT_U32(skb, tlv, v->val);
643
644 return 0;
645
646nla_put_failure:
647 return -1;
648}
649
650/**************************************************************************
651 * Type specific operations table
652 **************************************************************************/
653
654struct meta_type_ops {
655 void (*destroy)(struct meta_value *);
656 int (*compare)(struct meta_obj *, struct meta_obj *);
657 int (*change)(struct meta_value *, struct nlattr *);
658 void (*apply_extras)(struct meta_value *, struct meta_obj *);
659 int (*dump)(struct sk_buff *, struct meta_value *, int);
660};
661
662static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX + 1] = {
663 [TCF_META_TYPE_VAR] = {
664 .destroy = meta_var_destroy,
665 .compare = meta_var_compare,
666 .change = meta_var_change,
667 .apply_extras = meta_var_apply_extras,
668 .dump = meta_var_dump
669 },
670 [TCF_META_TYPE_INT] = {
671 .compare = meta_int_compare,
672 .change = meta_int_change,
673 .apply_extras = meta_int_apply_extras,
674 .dump = meta_int_dump
675 }
676};
677
678static inline struct meta_type_ops *meta_type_ops(struct meta_value *v)
679{
680 return &__meta_type_ops[meta_type(v)];
681}
682
683/**************************************************************************
684 * Core
685 **************************************************************************/
686
687static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
688 struct meta_value *v, struct meta_obj *dst)
689{
690 int err = 0;
691
692 if (meta_id(v) == TCF_META_ID_VALUE) {
693 dst->value = v->val;
694 dst->len = v->len;
695 return 0;
696 }
697
698 meta_ops(v)->get(skb, info, v, dst, &err);
699 if (err < 0)
700 return err;
701
702 if (meta_type_ops(v)->apply_extras)
703 meta_type_ops(v)->apply_extras(v, dst);
704
705 return 0;
706}
707
708static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
709 struct tcf_pkt_info *info)
710{
711 int r;
712 struct meta_match *meta = (struct meta_match *) m->data;
713 struct meta_obj l_value, r_value;
714
715 if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
716 meta_get(skb, info, &meta->rvalue, &r_value) < 0)
717 return 0;
718
719 r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
720
721 switch (meta->lvalue.hdr.op) {
722 case TCF_EM_OPND_EQ:
723 return !r;
724 case TCF_EM_OPND_LT:
725 return r < 0;
726 case TCF_EM_OPND_GT:
727 return r > 0;
728 }
729
730 return 0;
731}
732
733static void meta_delete(struct meta_match *meta)
734{
735 if (meta) {
736 struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
737
738 if (ops && ops->destroy) {
739 ops->destroy(&meta->lvalue);
740 ops->destroy(&meta->rvalue);
741 }
742 }
743
744 kfree(meta);
745}
746
747static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla)
748{
749 if (nla) {
750 if (nla_len(nla) == 0)
751 return -EINVAL;
752
753 return meta_type_ops(dst)->change(dst, nla);
754 }
755
756 return 0;
757}
758
759static inline int meta_is_supported(struct meta_value *val)
760{
761 return !meta_id(val) || meta_ops(val)->get;
762}
763
764static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = {
765 [TCA_EM_META_HDR] = { .len = sizeof(struct tcf_meta_hdr) },
766};
767
768static int em_meta_change(struct tcf_proto *tp, void *data, int len,
769 struct tcf_ematch *m)
770{
771 int err;
772 struct nlattr *tb[TCA_EM_META_MAX + 1];
773 struct tcf_meta_hdr *hdr;
774 struct meta_match *meta = NULL;
775
776 err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy);
777 if (err < 0)
778 goto errout;
779
780 err = -EINVAL;
781 if (tb[TCA_EM_META_HDR] == NULL)
782 goto errout;
783 hdr = nla_data(tb[TCA_EM_META_HDR]);
784
785 if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
786 TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
787 TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
788 TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
789 goto errout;
790
791 meta = kzalloc(sizeof(*meta), GFP_KERNEL);
792 if (meta == NULL)
793 goto errout;
794
795 memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
796 memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
797
798 if (!meta_is_supported(&meta->lvalue) ||
799 !meta_is_supported(&meta->rvalue)) {
800 err = -EOPNOTSUPP;
801 goto errout;
802 }
803
804 if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 ||
805 meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0)
806 goto errout;
807
808 m->datalen = sizeof(*meta);
809 m->data = (unsigned long) meta;
810
811 err = 0;
812errout:
813 if (err && meta)
814 meta_delete(meta);
815 return err;
816}
817
818static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
819{
820 if (m)
821 meta_delete((struct meta_match *) m->data);
822}
823
824static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
825{
826 struct meta_match *meta = (struct meta_match *) em->data;
827 struct tcf_meta_hdr hdr;
828 struct meta_type_ops *ops;
829
830 memset(&hdr, 0, sizeof(hdr));
831 memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
832 memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
833
834 NLA_PUT(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr);
835
836 ops = meta_type_ops(&meta->lvalue);
837 if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 ||
838 ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0)
839 goto nla_put_failure;
840
841 return 0;
842
843nla_put_failure:
844 return -1;
845}
846
847static struct tcf_ematch_ops em_meta_ops = {
848 .kind = TCF_EM_META,
849 .change = em_meta_change,
850 .match = em_meta_match,
851 .destroy = em_meta_destroy,
852 .dump = em_meta_dump,
853 .owner = THIS_MODULE,
854 .link = LIST_HEAD_INIT(em_meta_ops.link)
855};
856
857static int __init init_em_meta(void)
858{
859 return tcf_em_register(&em_meta_ops);
860}
861
862static void __exit exit_em_meta(void)
863{
864 tcf_em_unregister(&em_meta_ops);
865}
866
867MODULE_LICENSE("GPL");
868
869module_init(init_em_meta);
870module_exit(exit_em_meta);
871
872MODULE_ALIAS_TCF_EMATCH(TCF_EM_META);