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v3.5.6
  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		goto nla_put_failure;
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		if (nla_put(skb, tlv, sizeof(unsigned long), &v->val))
642			goto nla_put_failure;
643	} else if (v->len == sizeof(u32)) {
644		if (nla_put_u32(skb, tlv, v->val))
645			goto nla_put_failure;
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	void	(*destroy)(struct meta_value *);
660	int	(*compare)(struct meta_obj *, struct meta_obj *);
661	int	(*change)(struct meta_value *, struct nlattr *);
662	void	(*apply_extras)(struct meta_value *, struct meta_obj *);
663	int	(*dump)(struct sk_buff *, struct meta_value *, int);
664};
665
666static struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX + 1] = {
667	[TCF_META_TYPE_VAR] = {
668		.destroy = meta_var_destroy,
669		.compare = meta_var_compare,
670		.change = meta_var_change,
671		.apply_extras = meta_var_apply_extras,
672		.dump = meta_var_dump
673	},
674	[TCF_META_TYPE_INT] = {
675		.compare = meta_int_compare,
676		.change = meta_int_change,
677		.apply_extras = meta_int_apply_extras,
678		.dump = meta_int_dump
679	}
680};
681
682static inline struct meta_type_ops *meta_type_ops(struct meta_value *v)
683{
684	return &__meta_type_ops[meta_type(v)];
685}
686
687/**************************************************************************
688 * Core
689 **************************************************************************/
690
691static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
692		    struct meta_value *v, struct meta_obj *dst)
693{
694	int err = 0;
695
696	if (meta_id(v) == TCF_META_ID_VALUE) {
697		dst->value = v->val;
698		dst->len = v->len;
699		return 0;
700	}
701
702	meta_ops(v)->get(skb, info, v, dst, &err);
703	if (err < 0)
704		return err;
705
706	if (meta_type_ops(v)->apply_extras)
707		meta_type_ops(v)->apply_extras(v, dst);
708
709	return 0;
710}
711
712static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
713			 struct tcf_pkt_info *info)
714{
715	int r;
716	struct meta_match *meta = (struct meta_match *) m->data;
717	struct meta_obj l_value, r_value;
718
719	if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
720	    meta_get(skb, info, &meta->rvalue, &r_value) < 0)
721		return 0;
722
723	r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
724
725	switch (meta->lvalue.hdr.op) {
726	case TCF_EM_OPND_EQ:
727		return !r;
728	case TCF_EM_OPND_LT:
729		return r < 0;
730	case TCF_EM_OPND_GT:
731		return r > 0;
732	}
733
734	return 0;
735}
736
737static void meta_delete(struct meta_match *meta)
738{
739	if (meta) {
740		struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
741
742		if (ops && ops->destroy) {
743			ops->destroy(&meta->lvalue);
744			ops->destroy(&meta->rvalue);
745		}
746	}
747
748	kfree(meta);
749}
750
751static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla)
752{
753	if (nla) {
754		if (nla_len(nla) == 0)
755			return -EINVAL;
756
757		return meta_type_ops(dst)->change(dst, nla);
758	}
759
760	return 0;
761}
762
763static inline int meta_is_supported(struct meta_value *val)
764{
765	return !meta_id(val) || meta_ops(val)->get;
766}
767
768static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = {
769	[TCA_EM_META_HDR]	= { .len = sizeof(struct tcf_meta_hdr) },
770};
771
772static int em_meta_change(struct tcf_proto *tp, void *data, int len,
773			  struct tcf_ematch *m)
774{
775	int err;
776	struct nlattr *tb[TCA_EM_META_MAX + 1];
777	struct tcf_meta_hdr *hdr;
778	struct meta_match *meta = NULL;
779
780	err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy);
781	if (err < 0)
782		goto errout;
783
784	err = -EINVAL;
785	if (tb[TCA_EM_META_HDR] == NULL)
786		goto errout;
787	hdr = nla_data(tb[TCA_EM_META_HDR]);
788
789	if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
790	    TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
791	    TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
792	    TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
793		goto errout;
794
795	meta = kzalloc(sizeof(*meta), GFP_KERNEL);
796	if (meta == NULL)
 
797		goto errout;
 
798
799	memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
800	memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
801
802	if (!meta_is_supported(&meta->lvalue) ||
803	    !meta_is_supported(&meta->rvalue)) {
804		err = -EOPNOTSUPP;
805		goto errout;
806	}
807
808	if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 ||
809	    meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0)
810		goto errout;
811
812	m->datalen = sizeof(*meta);
813	m->data = (unsigned long) meta;
814
815	err = 0;
816errout:
817	if (err && meta)
818		meta_delete(meta);
819	return err;
820}
821
822static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
823{
824	if (m)
825		meta_delete((struct meta_match *) m->data);
826}
827
828static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
829{
830	struct meta_match *meta = (struct meta_match *) em->data;
831	struct tcf_meta_hdr hdr;
832	struct meta_type_ops *ops;
833
834	memset(&hdr, 0, sizeof(hdr));
835	memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
836	memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
837
838	if (nla_put(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr))
839		goto nla_put_failure;
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);
v4.17
   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/sched/loadavg.h>
  67#include <linux/string.h>
  68#include <linux/skbuff.h>
  69#include <linux/random.h>
  70#include <linux/if_vlan.h>
  71#include <linux/tc_ematch/tc_em_meta.h>
  72#include <net/dst.h>
  73#include <net/route.h>
  74#include <net/pkt_cls.h>
  75#include <net/sock.h>
  76
  77struct meta_obj {
  78	unsigned long		value;
  79	unsigned int		len;
  80};
  81
  82struct meta_value {
  83	struct tcf_meta_val	hdr;
  84	unsigned long		val;
  85	unsigned int		len;
  86};
  87
  88struct meta_match {
  89	struct meta_value	lvalue;
  90	struct meta_value	rvalue;
  91};
  92
  93static inline int meta_id(struct meta_value *v)
  94{
  95	return TCF_META_ID(v->hdr.kind);
  96}
  97
  98static inline int meta_type(struct meta_value *v)
  99{
 100	return TCF_META_TYPE(v->hdr.kind);
 101}
 102
 103#define META_COLLECTOR(FUNC) static void meta_##FUNC(struct sk_buff *skb, \
 104	struct tcf_pkt_info *info, struct meta_value *v, \
 105	struct meta_obj *dst, int *err)
 106
 107/**************************************************************************
 108 * System status & misc
 109 **************************************************************************/
 110
 111META_COLLECTOR(int_random)
 112{
 113	get_random_bytes(&dst->value, sizeof(dst->value));
 114}
 115
 116static inline unsigned long fixed_loadavg(int load)
 117{
 118	int rnd_load = load + (FIXED_1/200);
 119	int rnd_frac = ((rnd_load & (FIXED_1-1)) * 100) >> FSHIFT;
 120
 121	return ((rnd_load >> FSHIFT) * 100) + rnd_frac;
 122}
 123
 124META_COLLECTOR(int_loadavg_0)
 125{
 126	dst->value = fixed_loadavg(avenrun[0]);
 127}
 128
 129META_COLLECTOR(int_loadavg_1)
 130{
 131	dst->value = fixed_loadavg(avenrun[1]);
 132}
 133
 134META_COLLECTOR(int_loadavg_2)
 135{
 136	dst->value = fixed_loadavg(avenrun[2]);
 137}
 138
 139/**************************************************************************
 140 * Device names & indices
 141 **************************************************************************/
 142
 143static inline int int_dev(struct net_device *dev, struct meta_obj *dst)
 144{
 145	if (unlikely(dev == NULL))
 146		return -1;
 147
 148	dst->value = dev->ifindex;
 149	return 0;
 150}
 151
 152static inline int var_dev(struct net_device *dev, struct meta_obj *dst)
 153{
 154	if (unlikely(dev == NULL))
 155		return -1;
 156
 157	dst->value = (unsigned long) dev->name;
 158	dst->len = strlen(dev->name);
 159	return 0;
 160}
 161
 162META_COLLECTOR(int_dev)
 163{
 164	*err = int_dev(skb->dev, dst);
 165}
 166
 167META_COLLECTOR(var_dev)
 168{
 169	*err = var_dev(skb->dev, dst);
 170}
 171
 172/**************************************************************************
 173 * vlan tag
 174 **************************************************************************/
 175
 176META_COLLECTOR(int_vlan_tag)
 177{
 178	unsigned short tag;
 179
 180	if (skb_vlan_tag_present(skb))
 181		dst->value = skb_vlan_tag_get(skb);
 182	else if (!__vlan_get_tag(skb, &tag))
 
 183		dst->value = tag;
 184	else
 185		*err = -1;
 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 = tc_skb_protocol(skb);
 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
 225META_COLLECTOR(int_rxhash)
 226{
 227	dst->value = skb_get_hash(skb);
 228}
 229
 230/**************************************************************************
 231 * Netfilter
 232 **************************************************************************/
 233
 234META_COLLECTOR(int_mark)
 235{
 236	dst->value = skb->mark;
 237}
 238
 239/**************************************************************************
 240 * Traffic Control
 241 **************************************************************************/
 242
 243META_COLLECTOR(int_tcindex)
 244{
 245	dst->value = skb->tc_index;
 246}
 247
 248/**************************************************************************
 249 * Routing
 250 **************************************************************************/
 251
 252META_COLLECTOR(int_rtclassid)
 253{
 254	if (unlikely(skb_dst(skb) == NULL))
 255		*err = -1;
 256	else
 257#ifdef CONFIG_IP_ROUTE_CLASSID
 258		dst->value = skb_dst(skb)->tclassid;
 259#else
 260		dst->value = 0;
 261#endif
 262}
 263
 264META_COLLECTOR(int_rtiif)
 265{
 266	if (unlikely(skb_rtable(skb) == NULL))
 267		*err = -1;
 268	else
 269		dst->value = inet_iif(skb);
 270}
 271
 272/**************************************************************************
 273 * Socket Attributes
 274 **************************************************************************/
 275
 276#define skip_nonlocal(skb) \
 277	(unlikely(skb->sk == NULL))
 
 
 
 278
 279META_COLLECTOR(int_sk_family)
 280{
 281	if (skip_nonlocal(skb)) {
 282		*err = -1;
 283		return;
 284	}
 285	dst->value = skb->sk->sk_family;
 286}
 287
 288META_COLLECTOR(int_sk_state)
 289{
 290	if (skip_nonlocal(skb)) {
 291		*err = -1;
 292		return;
 293	}
 294	dst->value = skb->sk->sk_state;
 295}
 296
 297META_COLLECTOR(int_sk_reuse)
 298{
 299	if (skip_nonlocal(skb)) {
 300		*err = -1;
 301		return;
 302	}
 303	dst->value = skb->sk->sk_reuse;
 304}
 305
 306META_COLLECTOR(int_sk_bound_if)
 307{
 308	if (skip_nonlocal(skb)) {
 309		*err = -1;
 310		return;
 311	}
 312	/* No error if bound_dev_if is 0, legal userspace check */
 313	dst->value = skb->sk->sk_bound_dev_if;
 314}
 315
 316META_COLLECTOR(var_sk_bound_if)
 317{
 318	if (skip_nonlocal(skb)) {
 319		*err = -1;
 320		return;
 321	}
 322
 323	if (skb->sk->sk_bound_dev_if == 0) {
 324		dst->value = (unsigned long) "any";
 325		dst->len = 3;
 326	} else {
 327		struct net_device *dev;
 328
 329		rcu_read_lock();
 330		dev = dev_get_by_index_rcu(sock_net(skb->sk),
 331					   skb->sk->sk_bound_dev_if);
 332		*err = var_dev(dev, dst);
 333		rcu_read_unlock();
 334	}
 335}
 336
 337META_COLLECTOR(int_sk_refcnt)
 338{
 339	if (skip_nonlocal(skb)) {
 340		*err = -1;
 341		return;
 342	}
 343	dst->value = refcount_read(&skb->sk->sk_refcnt);
 344}
 345
 346META_COLLECTOR(int_sk_rcvbuf)
 347{
 348	const struct sock *sk = skb_to_full_sk(skb);
 349
 350	if (!sk) {
 351		*err = -1;
 352		return;
 353	}
 354	dst->value = sk->sk_rcvbuf;
 355}
 356
 357META_COLLECTOR(int_sk_shutdown)
 358{
 359	const struct sock *sk = skb_to_full_sk(skb);
 360
 361	if (!sk) {
 362		*err = -1;
 363		return;
 364	}
 365	dst->value = sk->sk_shutdown;
 366}
 367
 368META_COLLECTOR(int_sk_proto)
 369{
 370	const struct sock *sk = skb_to_full_sk(skb);
 371
 372	if (!sk) {
 373		*err = -1;
 374		return;
 375	}
 376	dst->value = sk->sk_protocol;
 377}
 378
 379META_COLLECTOR(int_sk_type)
 380{
 381	const struct sock *sk = skb_to_full_sk(skb);
 382
 383	if (!sk) {
 384		*err = -1;
 385		return;
 386	}
 387	dst->value = sk->sk_type;
 388}
 389
 390META_COLLECTOR(int_sk_rmem_alloc)
 391{
 392	const struct sock *sk = skb_to_full_sk(skb);
 393
 394	if (!sk) {
 395		*err = -1;
 396		return;
 397	}
 398	dst->value = sk_rmem_alloc_get(sk);
 399}
 400
 401META_COLLECTOR(int_sk_wmem_alloc)
 402{
 403	const struct sock *sk = skb_to_full_sk(skb);
 404
 405	if (!sk) {
 406		*err = -1;
 407		return;
 408	}
 409	dst->value = sk_wmem_alloc_get(sk);
 410}
 411
 412META_COLLECTOR(int_sk_omem_alloc)
 413{
 414	const struct sock *sk = skb_to_full_sk(skb);
 415
 416	if (!sk) {
 417		*err = -1;
 418		return;
 419	}
 420	dst->value = atomic_read(&sk->sk_omem_alloc);
 421}
 422
 423META_COLLECTOR(int_sk_rcv_qlen)
 424{
 425	const struct sock *sk = skb_to_full_sk(skb);
 426
 427	if (!sk) {
 428		*err = -1;
 429		return;
 430	}
 431	dst->value = sk->sk_receive_queue.qlen;
 432}
 433
 434META_COLLECTOR(int_sk_snd_qlen)
 435{
 436	const struct sock *sk = skb_to_full_sk(skb);
 437
 438	if (!sk) {
 439		*err = -1;
 440		return;
 441	}
 442	dst->value = sk->sk_write_queue.qlen;
 443}
 444
 445META_COLLECTOR(int_sk_wmem_queued)
 446{
 447	const struct sock *sk = skb_to_full_sk(skb);
 448
 449	if (!sk) {
 450		*err = -1;
 451		return;
 452	}
 453	dst->value = sk->sk_wmem_queued;
 454}
 455
 456META_COLLECTOR(int_sk_fwd_alloc)
 457{
 458	const struct sock *sk = skb_to_full_sk(skb);
 459
 460	if (!sk) {
 461		*err = -1;
 462		return;
 463	}
 464	dst->value = sk->sk_forward_alloc;
 465}
 466
 467META_COLLECTOR(int_sk_sndbuf)
 468{
 469	const struct sock *sk = skb_to_full_sk(skb);
 470
 471	if (!sk) {
 472		*err = -1;
 473		return;
 474	}
 475	dst->value = sk->sk_sndbuf;
 476}
 477
 478META_COLLECTOR(int_sk_alloc)
 479{
 480	const struct sock *sk = skb_to_full_sk(skb);
 481
 482	if (!sk) {
 483		*err = -1;
 484		return;
 485	}
 486	dst->value = (__force int) sk->sk_allocation;
 487}
 488
 489META_COLLECTOR(int_sk_hash)
 490{
 491	if (skip_nonlocal(skb)) {
 492		*err = -1;
 493		return;
 494	}
 495	dst->value = skb->sk->sk_hash;
 496}
 497
 498META_COLLECTOR(int_sk_lingertime)
 499{
 500	const struct sock *sk = skb_to_full_sk(skb);
 501
 502	if (!sk) {
 503		*err = -1;
 504		return;
 505	}
 506	dst->value = sk->sk_lingertime / HZ;
 507}
 508
 509META_COLLECTOR(int_sk_err_qlen)
 510{
 511	const struct sock *sk = skb_to_full_sk(skb);
 512
 513	if (!sk) {
 514		*err = -1;
 515		return;
 516	}
 517	dst->value = sk->sk_error_queue.qlen;
 518}
 519
 520META_COLLECTOR(int_sk_ack_bl)
 521{
 522	const struct sock *sk = skb_to_full_sk(skb);
 523
 524	if (!sk) {
 525		*err = -1;
 526		return;
 527	}
 528	dst->value = sk->sk_ack_backlog;
 529}
 530
 531META_COLLECTOR(int_sk_max_ack_bl)
 532{
 533	const struct sock *sk = skb_to_full_sk(skb);
 534
 535	if (!sk) {
 536		*err = -1;
 537		return;
 538	}
 539	dst->value = sk->sk_max_ack_backlog;
 540}
 541
 542META_COLLECTOR(int_sk_prio)
 543{
 544	const struct sock *sk = skb_to_full_sk(skb);
 545
 546	if (!sk) {
 547		*err = -1;
 548		return;
 549	}
 550	dst->value = sk->sk_priority;
 551}
 552
 553META_COLLECTOR(int_sk_rcvlowat)
 554{
 555	const struct sock *sk = skb_to_full_sk(skb);
 556
 557	if (!sk) {
 558		*err = -1;
 559		return;
 560	}
 561	dst->value = sk->sk_rcvlowat;
 562}
 563
 564META_COLLECTOR(int_sk_rcvtimeo)
 565{
 566	const struct sock *sk = skb_to_full_sk(skb);
 567
 568	if (!sk) {
 569		*err = -1;
 570		return;
 571	}
 572	dst->value = sk->sk_rcvtimeo / HZ;
 573}
 574
 575META_COLLECTOR(int_sk_sndtimeo)
 576{
 577	const struct sock *sk = skb_to_full_sk(skb);
 578
 579	if (!sk) {
 580		*err = -1;
 581		return;
 582	}
 583	dst->value = sk->sk_sndtimeo / HZ;
 584}
 585
 586META_COLLECTOR(int_sk_sendmsg_off)
 587{
 588	const struct sock *sk = skb_to_full_sk(skb);
 589
 590	if (!sk) {
 591		*err = -1;
 592		return;
 593	}
 594	dst->value = sk->sk_frag.offset;
 595}
 596
 597META_COLLECTOR(int_sk_write_pend)
 598{
 599	const struct sock *sk = skb_to_full_sk(skb);
 600
 601	if (!sk) {
 602		*err = -1;
 603		return;
 604	}
 605	dst->value = sk->sk_write_pending;
 606}
 607
 608/**************************************************************************
 609 * Meta value collectors assignment table
 610 **************************************************************************/
 611
 612struct meta_ops {
 613	void		(*get)(struct sk_buff *, struct tcf_pkt_info *,
 614			       struct meta_value *, struct meta_obj *, int *);
 615};
 616
 617#define META_ID(name) TCF_META_ID_##name
 618#define META_FUNC(name) { .get = meta_##name }
 619
 620/* Meta value operations table listing all meta value collectors and
 621 * assigns them to a type and meta id. */
 622static struct meta_ops __meta_ops[TCF_META_TYPE_MAX + 1][TCF_META_ID_MAX + 1] = {
 623	[TCF_META_TYPE_VAR] = {
 624		[META_ID(DEV)]			= META_FUNC(var_dev),
 625		[META_ID(SK_BOUND_IF)] 		= META_FUNC(var_sk_bound_if),
 626	},
 627	[TCF_META_TYPE_INT] = {
 628		[META_ID(RANDOM)]		= META_FUNC(int_random),
 629		[META_ID(LOADAVG_0)]		= META_FUNC(int_loadavg_0),
 630		[META_ID(LOADAVG_1)]		= META_FUNC(int_loadavg_1),
 631		[META_ID(LOADAVG_2)]		= META_FUNC(int_loadavg_2),
 632		[META_ID(DEV)]			= META_FUNC(int_dev),
 633		[META_ID(PRIORITY)]		= META_FUNC(int_priority),
 634		[META_ID(PROTOCOL)]		= META_FUNC(int_protocol),
 635		[META_ID(PKTTYPE)]		= META_FUNC(int_pkttype),
 636		[META_ID(PKTLEN)]		= META_FUNC(int_pktlen),
 637		[META_ID(DATALEN)]		= META_FUNC(int_datalen),
 638		[META_ID(MACLEN)]		= META_FUNC(int_maclen),
 639		[META_ID(NFMARK)]		= META_FUNC(int_mark),
 640		[META_ID(TCINDEX)]		= META_FUNC(int_tcindex),
 641		[META_ID(RTCLASSID)]		= META_FUNC(int_rtclassid),
 642		[META_ID(RTIIF)]		= META_FUNC(int_rtiif),
 643		[META_ID(SK_FAMILY)]		= META_FUNC(int_sk_family),
 644		[META_ID(SK_STATE)]		= META_FUNC(int_sk_state),
 645		[META_ID(SK_REUSE)]		= META_FUNC(int_sk_reuse),
 646		[META_ID(SK_BOUND_IF)]		= META_FUNC(int_sk_bound_if),
 647		[META_ID(SK_REFCNT)]		= META_FUNC(int_sk_refcnt),
 648		[META_ID(SK_RCVBUF)]		= META_FUNC(int_sk_rcvbuf),
 649		[META_ID(SK_SNDBUF)]		= META_FUNC(int_sk_sndbuf),
 650		[META_ID(SK_SHUTDOWN)]		= META_FUNC(int_sk_shutdown),
 651		[META_ID(SK_PROTO)]		= META_FUNC(int_sk_proto),
 652		[META_ID(SK_TYPE)]		= META_FUNC(int_sk_type),
 653		[META_ID(SK_RMEM_ALLOC)]	= META_FUNC(int_sk_rmem_alloc),
 654		[META_ID(SK_WMEM_ALLOC)]	= META_FUNC(int_sk_wmem_alloc),
 655		[META_ID(SK_OMEM_ALLOC)]	= META_FUNC(int_sk_omem_alloc),
 656		[META_ID(SK_WMEM_QUEUED)]	= META_FUNC(int_sk_wmem_queued),
 657		[META_ID(SK_RCV_QLEN)]		= META_FUNC(int_sk_rcv_qlen),
 658		[META_ID(SK_SND_QLEN)]		= META_FUNC(int_sk_snd_qlen),
 659		[META_ID(SK_ERR_QLEN)]		= META_FUNC(int_sk_err_qlen),
 660		[META_ID(SK_FORWARD_ALLOCS)]	= META_FUNC(int_sk_fwd_alloc),
 661		[META_ID(SK_ALLOCS)]		= META_FUNC(int_sk_alloc),
 662		[META_ID(SK_HASH)]		= META_FUNC(int_sk_hash),
 663		[META_ID(SK_LINGERTIME)]	= META_FUNC(int_sk_lingertime),
 664		[META_ID(SK_ACK_BACKLOG)]	= META_FUNC(int_sk_ack_bl),
 665		[META_ID(SK_MAX_ACK_BACKLOG)]	= META_FUNC(int_sk_max_ack_bl),
 666		[META_ID(SK_PRIO)]		= META_FUNC(int_sk_prio),
 667		[META_ID(SK_RCVLOWAT)]		= META_FUNC(int_sk_rcvlowat),
 668		[META_ID(SK_RCVTIMEO)]		= META_FUNC(int_sk_rcvtimeo),
 669		[META_ID(SK_SNDTIMEO)]		= META_FUNC(int_sk_sndtimeo),
 670		[META_ID(SK_SENDMSG_OFF)]	= META_FUNC(int_sk_sendmsg_off),
 671		[META_ID(SK_WRITE_PENDING)]	= META_FUNC(int_sk_write_pend),
 672		[META_ID(VLAN_TAG)]		= META_FUNC(int_vlan_tag),
 673		[META_ID(RXHASH)]		= META_FUNC(int_rxhash),
 674	}
 675};
 676
 677static inline struct meta_ops *meta_ops(struct meta_value *val)
 678{
 679	return &__meta_ops[meta_type(val)][meta_id(val)];
 680}
 681
 682/**************************************************************************
 683 * Type specific operations for TCF_META_TYPE_VAR
 684 **************************************************************************/
 685
 686static int meta_var_compare(struct meta_obj *a, struct meta_obj *b)
 687{
 688	int r = a->len - b->len;
 689
 690	if (r == 0)
 691		r = memcmp((void *) a->value, (void *) b->value, a->len);
 692
 693	return r;
 694}
 695
 696static int meta_var_change(struct meta_value *dst, struct nlattr *nla)
 697{
 698	int len = nla_len(nla);
 699
 700	dst->val = (unsigned long)kmemdup(nla_data(nla), len, GFP_KERNEL);
 701	if (dst->val == 0UL)
 702		return -ENOMEM;
 703	dst->len = len;
 704	return 0;
 705}
 706
 707static void meta_var_destroy(struct meta_value *v)
 708{
 709	kfree((void *) v->val);
 710}
 711
 712static void meta_var_apply_extras(struct meta_value *v,
 713				  struct meta_obj *dst)
 714{
 715	int shift = v->hdr.shift;
 716
 717	if (shift && shift < dst->len)
 718		dst->len -= shift;
 719}
 720
 721static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
 722{
 723	if (v->val && v->len &&
 724	    nla_put(skb, tlv, v->len, (void *) v->val))
 725		goto nla_put_failure;
 726	return 0;
 727
 728nla_put_failure:
 729	return -1;
 730}
 731
 732/**************************************************************************
 733 * Type specific operations for TCF_META_TYPE_INT
 734 **************************************************************************/
 735
 736static int meta_int_compare(struct meta_obj *a, struct meta_obj *b)
 737{
 738	/* Let gcc optimize it, the unlikely is not really based on
 739	 * some numbers but jump free code for mismatches seems
 740	 * more logical. */
 741	if (unlikely(a->value == b->value))
 742		return 0;
 743	else if (a->value < b->value)
 744		return -1;
 745	else
 746		return 1;
 747}
 748
 749static int meta_int_change(struct meta_value *dst, struct nlattr *nla)
 750{
 751	if (nla_len(nla) >= sizeof(unsigned long)) {
 752		dst->val = *(unsigned long *) nla_data(nla);
 753		dst->len = sizeof(unsigned long);
 754	} else if (nla_len(nla) == sizeof(u32)) {
 755		dst->val = nla_get_u32(nla);
 756		dst->len = sizeof(u32);
 757	} else
 758		return -EINVAL;
 759
 760	return 0;
 761}
 762
 763static void meta_int_apply_extras(struct meta_value *v,
 764				  struct meta_obj *dst)
 765{
 766	if (v->hdr.shift)
 767		dst->value >>= v->hdr.shift;
 768
 769	if (v->val)
 770		dst->value &= v->val;
 771}
 772
 773static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv)
 774{
 775	if (v->len == sizeof(unsigned long)) {
 776		if (nla_put(skb, tlv, sizeof(unsigned long), &v->val))
 777			goto nla_put_failure;
 778	} else if (v->len == sizeof(u32)) {
 779		if (nla_put_u32(skb, tlv, v->val))
 780			goto nla_put_failure;
 781	}
 782
 783	return 0;
 784
 785nla_put_failure:
 786	return -1;
 787}
 788
 789/**************************************************************************
 790 * Type specific operations table
 791 **************************************************************************/
 792
 793struct meta_type_ops {
 794	void	(*destroy)(struct meta_value *);
 795	int	(*compare)(struct meta_obj *, struct meta_obj *);
 796	int	(*change)(struct meta_value *, struct nlattr *);
 797	void	(*apply_extras)(struct meta_value *, struct meta_obj *);
 798	int	(*dump)(struct sk_buff *, struct meta_value *, int);
 799};
 800
 801static const struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX + 1] = {
 802	[TCF_META_TYPE_VAR] = {
 803		.destroy = meta_var_destroy,
 804		.compare = meta_var_compare,
 805		.change = meta_var_change,
 806		.apply_extras = meta_var_apply_extras,
 807		.dump = meta_var_dump
 808	},
 809	[TCF_META_TYPE_INT] = {
 810		.compare = meta_int_compare,
 811		.change = meta_int_change,
 812		.apply_extras = meta_int_apply_extras,
 813		.dump = meta_int_dump
 814	}
 815};
 816
 817static inline const struct meta_type_ops *meta_type_ops(struct meta_value *v)
 818{
 819	return &__meta_type_ops[meta_type(v)];
 820}
 821
 822/**************************************************************************
 823 * Core
 824 **************************************************************************/
 825
 826static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info,
 827		    struct meta_value *v, struct meta_obj *dst)
 828{
 829	int err = 0;
 830
 831	if (meta_id(v) == TCF_META_ID_VALUE) {
 832		dst->value = v->val;
 833		dst->len = v->len;
 834		return 0;
 835	}
 836
 837	meta_ops(v)->get(skb, info, v, dst, &err);
 838	if (err < 0)
 839		return err;
 840
 841	if (meta_type_ops(v)->apply_extras)
 842		meta_type_ops(v)->apply_extras(v, dst);
 843
 844	return 0;
 845}
 846
 847static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m,
 848			 struct tcf_pkt_info *info)
 849{
 850	int r;
 851	struct meta_match *meta = (struct meta_match *) m->data;
 852	struct meta_obj l_value, r_value;
 853
 854	if (meta_get(skb, info, &meta->lvalue, &l_value) < 0 ||
 855	    meta_get(skb, info, &meta->rvalue, &r_value) < 0)
 856		return 0;
 857
 858	r = meta_type_ops(&meta->lvalue)->compare(&l_value, &r_value);
 859
 860	switch (meta->lvalue.hdr.op) {
 861	case TCF_EM_OPND_EQ:
 862		return !r;
 863	case TCF_EM_OPND_LT:
 864		return r < 0;
 865	case TCF_EM_OPND_GT:
 866		return r > 0;
 867	}
 868
 869	return 0;
 870}
 871
 872static void meta_delete(struct meta_match *meta)
 873{
 874	if (meta) {
 875		const struct meta_type_ops *ops = meta_type_ops(&meta->lvalue);
 876
 877		if (ops && ops->destroy) {
 878			ops->destroy(&meta->lvalue);
 879			ops->destroy(&meta->rvalue);
 880		}
 881	}
 882
 883	kfree(meta);
 884}
 885
 886static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla)
 887{
 888	if (nla) {
 889		if (nla_len(nla) == 0)
 890			return -EINVAL;
 891
 892		return meta_type_ops(dst)->change(dst, nla);
 893	}
 894
 895	return 0;
 896}
 897
 898static inline int meta_is_supported(struct meta_value *val)
 899{
 900	return !meta_id(val) || meta_ops(val)->get;
 901}
 902
 903static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = {
 904	[TCA_EM_META_HDR]	= { .len = sizeof(struct tcf_meta_hdr) },
 905};
 906
 907static int em_meta_change(struct net *net, void *data, int len,
 908			  struct tcf_ematch *m)
 909{
 910	int err;
 911	struct nlattr *tb[TCA_EM_META_MAX + 1];
 912	struct tcf_meta_hdr *hdr;
 913	struct meta_match *meta = NULL;
 914
 915	err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy, NULL);
 916	if (err < 0)
 917		goto errout;
 918
 919	err = -EINVAL;
 920	if (tb[TCA_EM_META_HDR] == NULL)
 921		goto errout;
 922	hdr = nla_data(tb[TCA_EM_META_HDR]);
 923
 924	if (TCF_META_TYPE(hdr->left.kind) != TCF_META_TYPE(hdr->right.kind) ||
 925	    TCF_META_TYPE(hdr->left.kind) > TCF_META_TYPE_MAX ||
 926	    TCF_META_ID(hdr->left.kind) > TCF_META_ID_MAX ||
 927	    TCF_META_ID(hdr->right.kind) > TCF_META_ID_MAX)
 928		goto errout;
 929
 930	meta = kzalloc(sizeof(*meta), GFP_KERNEL);
 931	if (meta == NULL) {
 932		err = -ENOMEM;
 933		goto errout;
 934	}
 935
 936	memcpy(&meta->lvalue.hdr, &hdr->left, sizeof(hdr->left));
 937	memcpy(&meta->rvalue.hdr, &hdr->right, sizeof(hdr->right));
 938
 939	if (!meta_is_supported(&meta->lvalue) ||
 940	    !meta_is_supported(&meta->rvalue)) {
 941		err = -EOPNOTSUPP;
 942		goto errout;
 943	}
 944
 945	if (meta_change_data(&meta->lvalue, tb[TCA_EM_META_LVALUE]) < 0 ||
 946	    meta_change_data(&meta->rvalue, tb[TCA_EM_META_RVALUE]) < 0)
 947		goto errout;
 948
 949	m->datalen = sizeof(*meta);
 950	m->data = (unsigned long) meta;
 951
 952	err = 0;
 953errout:
 954	if (err && meta)
 955		meta_delete(meta);
 956	return err;
 957}
 958
 959static void em_meta_destroy(struct tcf_ematch *m)
 960{
 961	if (m)
 962		meta_delete((struct meta_match *) m->data);
 963}
 964
 965static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em)
 966{
 967	struct meta_match *meta = (struct meta_match *) em->data;
 968	struct tcf_meta_hdr hdr;
 969	const struct meta_type_ops *ops;
 970
 971	memset(&hdr, 0, sizeof(hdr));
 972	memcpy(&hdr.left, &meta->lvalue.hdr, sizeof(hdr.left));
 973	memcpy(&hdr.right, &meta->rvalue.hdr, sizeof(hdr.right));
 974
 975	if (nla_put(skb, TCA_EM_META_HDR, sizeof(hdr), &hdr))
 976		goto nla_put_failure;
 977
 978	ops = meta_type_ops(&meta->lvalue);
 979	if (ops->dump(skb, &meta->lvalue, TCA_EM_META_LVALUE) < 0 ||
 980	    ops->dump(skb, &meta->rvalue, TCA_EM_META_RVALUE) < 0)
 981		goto nla_put_failure;
 982
 983	return 0;
 984
 985nla_put_failure:
 986	return -1;
 987}
 988
 989static struct tcf_ematch_ops em_meta_ops = {
 990	.kind	  = TCF_EM_META,
 991	.change	  = em_meta_change,
 992	.match	  = em_meta_match,
 993	.destroy  = em_meta_destroy,
 994	.dump	  = em_meta_dump,
 995	.owner	  = THIS_MODULE,
 996	.link	  = LIST_HEAD_INIT(em_meta_ops.link)
 997};
 998
 999static int __init init_em_meta(void)
1000{
1001	return tcf_em_register(&em_meta_ops);
1002}
1003
1004static void __exit exit_em_meta(void)
1005{
1006	tcf_em_unregister(&em_meta_ops);
1007}
1008
1009MODULE_LICENSE("GPL");
1010
1011module_init(init_em_meta);
1012module_exit(exit_em_meta);
1013
1014MODULE_ALIAS_TCF_EMATCH(TCF_EM_META);