2 * net/sched/em_meta.c Metadata ematch
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.
9 * Authors: Thomas Graf <tgraf@suug.ch>
11 * ==========================================================================
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.
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.
28 * +-----------+ +-----------+
29 * | type: INT | | type: INT |
30 * def | id: INDEV | | id: VALUE |
31 * | data: | | data: 3 |
32 * +-----------+ +-----------+
34 * ---> meta_ops[INT][INDEV](...) |
38 * +-----------+ +-----------+
39 * | type: INT | | type: INT |
40 * obj | id: INDEV | | id: VALUE |
41 * | data: 2 |<--data got filled out | data: 3 |
42 * +-----------+ +-----------+
44 * --------------> 2 equals 3 <--------------
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.
50 * Additionaly, type dependant modifiers such as shift operators
51 * or mask may be applied to extend the functionaliy. As of now,
52 * the variable length type supports shifting the byte string to
53 * the right, eating up any number of octets and thus supporting
54 * wildcard interface name comparisons such as "ppp%" matching
57 * NOTE: Certain meta values depend on other subsystems and are
58 * only available if that subsytem is enabled in the kernel.
61 #include <linux/config.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/tc_ematch/tc_em_meta.h>
71 #include <net/route.h>
72 #include <net/pkt_cls.h>
82 struct tcf_meta_val hdr
;
89 struct meta_value lvalue
;
90 struct meta_value rvalue
;
93 static inline int meta_id(struct meta_value
*v
)
95 return TCF_META_ID(v
->hdr
.kind
);
98 static inline int meta_type(struct meta_value
*v
)
100 return TCF_META_TYPE(v
->hdr
.kind
);
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)
107 /**************************************************************************
108 * System status & misc
109 **************************************************************************/
111 META_COLLECTOR(int_random
)
113 get_random_bytes(&dst
->value
, sizeof(dst
->value
));
116 static inline unsigned long fixed_loadavg(int load
)
118 int rnd_load
= load
+ (FIXED_1
/200);
119 int rnd_frac
= ((rnd_load
& (FIXED_1
-1)) * 100) >> FSHIFT
;
121 return ((rnd_load
>> FSHIFT
) * 100) + rnd_frac
;
124 META_COLLECTOR(int_loadavg_0
)
126 dst
->value
= fixed_loadavg(avenrun
[0]);
129 META_COLLECTOR(int_loadavg_1
)
131 dst
->value
= fixed_loadavg(avenrun
[1]);
134 META_COLLECTOR(int_loadavg_2
)
136 dst
->value
= fixed_loadavg(avenrun
[2]);
139 /**************************************************************************
140 * Device names & indices
141 **************************************************************************/
143 static inline int int_dev(struct net_device
*dev
, struct meta_obj
*dst
)
145 if (unlikely(dev
== NULL
))
148 dst
->value
= dev
->ifindex
;
152 static inline int var_dev(struct net_device
*dev
, struct meta_obj
*dst
)
154 if (unlikely(dev
== NULL
))
157 dst
->value
= (unsigned long) dev
->name
;
158 dst
->len
= strlen(dev
->name
);
162 META_COLLECTOR(int_dev
)
164 *err
= int_dev(skb
->dev
, dst
);
167 META_COLLECTOR(var_dev
)
169 *err
= var_dev(skb
->dev
, dst
);
172 META_COLLECTOR(int_indev
)
174 *err
= int_dev(skb
->input_dev
, dst
);
177 META_COLLECTOR(var_indev
)
179 *err
= var_dev(skb
->input_dev
, dst
);
182 META_COLLECTOR(int_realdev
)
184 *err
= int_dev(skb
->real_dev
, dst
);
187 META_COLLECTOR(var_realdev
)
189 *err
= var_dev(skb
->real_dev
, dst
);
192 /**************************************************************************
194 **************************************************************************/
196 META_COLLECTOR(int_priority
)
198 dst
->value
= skb
->priority
;
201 META_COLLECTOR(int_protocol
)
203 /* Let userspace take care of the byte ordering */
204 dst
->value
= skb
->protocol
;
207 META_COLLECTOR(int_security
)
209 dst
->value
= skb
->security
;
212 META_COLLECTOR(int_pkttype
)
214 dst
->value
= skb
->pkt_type
;
217 META_COLLECTOR(int_pktlen
)
219 dst
->value
= skb
->len
;
222 META_COLLECTOR(int_datalen
)
224 dst
->value
= skb
->data_len
;
227 META_COLLECTOR(int_maclen
)
229 dst
->value
= skb
->mac_len
;
232 /**************************************************************************
234 **************************************************************************/
236 #ifdef CONFIG_NETFILTER
237 META_COLLECTOR(int_nfmark
)
239 dst
->value
= skb
->nfmark
;
243 /**************************************************************************
245 **************************************************************************/
247 META_COLLECTOR(int_tcindex
)
249 dst
->value
= skb
->tc_index
;
252 #ifdef CONFIG_NET_CLS_ACT
253 META_COLLECTOR(int_tcverd
)
255 dst
->value
= skb
->tc_verd
;
258 META_COLLECTOR(int_tcclassid
)
260 dst
->value
= skb
->tc_classid
;
264 /**************************************************************************
266 **************************************************************************/
268 #ifdef CONFIG_NET_CLS_ROUTE
269 META_COLLECTOR(int_rtclassid
)
271 if (unlikely(skb
->dst
== NULL
))
274 dst
->value
= skb
->dst
->tclassid
;
278 META_COLLECTOR(int_rtiif
)
280 if (unlikely(skb
->dst
== NULL
))
283 dst
->value
= ((struct rtable
*) skb
->dst
)->fl
.iif
;
286 /**************************************************************************
287 * Meta value collectors assignment table
288 **************************************************************************/
292 void (*get
)(struct sk_buff
*, struct tcf_pkt_info
*,
293 struct meta_value
*, struct meta_obj
*, int *);
296 /* Meta value operations table listing all meta value collectors and
297 * assigns them to a type and meta id. */
298 static struct meta_ops __meta_ops
[TCF_META_TYPE_MAX
+1][TCF_META_ID_MAX
+1] = {
299 [TCF_META_TYPE_VAR
] = {
300 [TCF_META_ID_DEV
] = { .get
= meta_var_dev
},
301 [TCF_META_ID_INDEV
] = { .get
= meta_var_indev
},
302 [TCF_META_ID_REALDEV
] = { .get
= meta_var_realdev
}
304 [TCF_META_TYPE_INT
] = {
305 [TCF_META_ID_RANDOM
] = { .get
= meta_int_random
},
306 [TCF_META_ID_LOADAVG_0
] = { .get
= meta_int_loadavg_0
},
307 [TCF_META_ID_LOADAVG_1
] = { .get
= meta_int_loadavg_1
},
308 [TCF_META_ID_LOADAVG_2
] = { .get
= meta_int_loadavg_2
},
309 [TCF_META_ID_DEV
] = { .get
= meta_int_dev
},
310 [TCF_META_ID_INDEV
] = { .get
= meta_int_indev
},
311 [TCF_META_ID_REALDEV
] = { .get
= meta_int_realdev
},
312 [TCF_META_ID_PRIORITY
] = { .get
= meta_int_priority
},
313 [TCF_META_ID_PROTOCOL
] = { .get
= meta_int_protocol
},
314 [TCF_META_ID_SECURITY
] = { .get
= meta_int_security
},
315 [TCF_META_ID_PKTTYPE
] = { .get
= meta_int_pkttype
},
316 [TCF_META_ID_PKTLEN
] = { .get
= meta_int_pktlen
},
317 [TCF_META_ID_DATALEN
] = { .get
= meta_int_datalen
},
318 [TCF_META_ID_MACLEN
] = { .get
= meta_int_maclen
},
319 #ifdef CONFIG_NETFILTER
320 [TCF_META_ID_NFMARK
] = { .get
= meta_int_nfmark
},
322 [TCF_META_ID_TCINDEX
] = { .get
= meta_int_tcindex
},
323 #ifdef CONFIG_NET_CLS_ACT
324 [TCF_META_ID_TCVERDICT
] = { .get
= meta_int_tcverd
},
325 [TCF_META_ID_TCCLASSID
] = { .get
= meta_int_tcclassid
},
327 #ifdef CONFIG_NET_CLS_ROUTE
328 [TCF_META_ID_RTCLASSID
] = { .get
= meta_int_rtclassid
},
330 [TCF_META_ID_RTIIF
] = { .get
= meta_int_rtiif
}
334 static inline struct meta_ops
* meta_ops(struct meta_value
*val
)
336 return &__meta_ops
[meta_type(val
)][meta_id(val
)];
339 /**************************************************************************
340 * Type specific operations for TCF_META_TYPE_VAR
341 **************************************************************************/
343 static int meta_var_compare(struct meta_obj
*a
, struct meta_obj
*b
)
345 int r
= a
->len
- b
->len
;
348 r
= memcmp((void *) a
->value
, (void *) b
->value
, a
->len
);
353 static int meta_var_change(struct meta_value
*dst
, struct rtattr
*rta
)
355 int len
= RTA_PAYLOAD(rta
);
357 dst
->val
= (unsigned long) kmalloc(len
, GFP_KERNEL
);
360 memcpy((void *) dst
->val
, RTA_DATA(rta
), len
);
365 static void meta_var_destroy(struct meta_value
*v
)
368 kfree((void *) v
->val
);
371 static void meta_var_apply_extras(struct meta_value
*v
,
372 struct meta_obj
*dst
)
374 int shift
= v
->hdr
.shift
;
376 if (shift
&& shift
< dst
->len
)
380 static int meta_var_dump(struct sk_buff
*skb
, struct meta_value
*v
, int tlv
)
382 if (v
->val
&& v
->len
)
383 RTA_PUT(skb
, tlv
, v
->len
, (void *) v
->val
);
390 /**************************************************************************
391 * Type specific operations for TCF_META_TYPE_INT
392 **************************************************************************/
394 static int meta_int_compare(struct meta_obj
*a
, struct meta_obj
*b
)
396 /* Let gcc optimize it, the unlikely is not really based on
397 * some numbers but jump free code for mismatches seems
399 if (unlikely(a
== b
))
407 static int meta_int_change(struct meta_value
*dst
, struct rtattr
*rta
)
409 if (RTA_PAYLOAD(rta
) >= sizeof(unsigned long)) {
410 dst
->val
= *(unsigned long *) RTA_DATA(rta
);
411 dst
->len
= sizeof(unsigned long);
412 } else if (RTA_PAYLOAD(rta
) == sizeof(u32
)) {
413 dst
->val
= *(u32
*) RTA_DATA(rta
);
414 dst
->len
= sizeof(u32
);
421 static void meta_int_apply_extras(struct meta_value
*v
,
422 struct meta_obj
*dst
)
425 dst
->value
>>= v
->hdr
.shift
;
428 dst
->value
&= v
->val
;
431 static int meta_int_dump(struct sk_buff
*skb
, struct meta_value
*v
, int tlv
)
433 if (v
->len
== sizeof(unsigned long))
434 RTA_PUT(skb
, tlv
, sizeof(unsigned long), &v
->val
);
435 else if (v
->len
== sizeof(u32
)) {
437 RTA_PUT(skb
, tlv
, sizeof(d
), &d
);
446 /**************************************************************************
447 * Type specific operations table
448 **************************************************************************/
452 void (*destroy
)(struct meta_value
*);
453 int (*compare
)(struct meta_obj
*, struct meta_obj
*);
454 int (*change
)(struct meta_value
*, struct rtattr
*);
455 void (*apply_extras
)(struct meta_value
*, struct meta_obj
*);
456 int (*dump
)(struct sk_buff
*, struct meta_value
*, int);
459 static struct meta_type_ops __meta_type_ops
[TCF_META_TYPE_MAX
+1] = {
460 [TCF_META_TYPE_VAR
] = {
461 .destroy
= meta_var_destroy
,
462 .compare
= meta_var_compare
,
463 .change
= meta_var_change
,
464 .apply_extras
= meta_var_apply_extras
,
465 .dump
= meta_var_dump
467 [TCF_META_TYPE_INT
] = {
468 .compare
= meta_int_compare
,
469 .change
= meta_int_change
,
470 .apply_extras
= meta_int_apply_extras
,
471 .dump
= meta_int_dump
475 static inline struct meta_type_ops
* meta_type_ops(struct meta_value
*v
)
477 return &__meta_type_ops
[meta_type(v
)];
480 /**************************************************************************
482 **************************************************************************/
484 static inline int meta_get(struct sk_buff
*skb
, struct tcf_pkt_info
*info
,
485 struct meta_value
*v
, struct meta_obj
*dst
)
489 if (meta_id(v
) == TCF_META_ID_VALUE
) {
495 meta_ops(v
)->get(skb
, info
, v
, dst
, &err
);
499 if (meta_type_ops(v
)->apply_extras
)
500 meta_type_ops(v
)->apply_extras(v
, dst
);
505 static int em_meta_match(struct sk_buff
*skb
, struct tcf_ematch
*m
,
506 struct tcf_pkt_info
*info
)
509 struct meta_match
*meta
= (struct meta_match
*) m
->data
;
510 struct meta_obj l_value
, r_value
;
512 if (meta_get(skb
, info
, &meta
->lvalue
, &l_value
) < 0 ||
513 meta_get(skb
, info
, &meta
->rvalue
, &r_value
) < 0)
516 r
= meta_type_ops(&meta
->lvalue
)->compare(&l_value
, &r_value
);
518 switch (meta
->lvalue
.hdr
.op
) {
530 static inline void meta_delete(struct meta_match
*meta
)
532 struct meta_type_ops
*ops
= meta_type_ops(&meta
->lvalue
);
534 if (ops
&& ops
->destroy
) {
535 ops
->destroy(&meta
->lvalue
);
536 ops
->destroy(&meta
->rvalue
);
542 static inline int meta_change_data(struct meta_value
*dst
, struct rtattr
*rta
)
545 if (RTA_PAYLOAD(rta
) == 0)
548 return meta_type_ops(dst
)->change(dst
, rta
);
554 static inline int meta_is_supported(struct meta_value
*val
)
556 return (!meta_id(val
) || meta_ops(val
)->get
);
559 static int em_meta_change(struct tcf_proto
*tp
, void *data
, int len
,
560 struct tcf_ematch
*m
)
563 struct rtattr
*tb
[TCA_EM_META_MAX
];
564 struct tcf_meta_hdr
*hdr
;
565 struct meta_match
*meta
= NULL
;
567 if (rtattr_parse(tb
, TCA_EM_META_MAX
, data
, len
) < 0)
570 if (tb
[TCA_EM_META_HDR
-1] == NULL
||
571 RTA_PAYLOAD(tb
[TCA_EM_META_HDR
-1]) < sizeof(*hdr
))
573 hdr
= RTA_DATA(tb
[TCA_EM_META_HDR
-1]);
575 if (TCF_META_TYPE(hdr
->left
.kind
) != TCF_META_TYPE(hdr
->right
.kind
) ||
576 TCF_META_TYPE(hdr
->left
.kind
) > TCF_META_TYPE_MAX
||
577 TCF_META_ID(hdr
->left
.kind
) > TCF_META_ID_MAX
||
578 TCF_META_ID(hdr
->right
.kind
) > TCF_META_ID_MAX
)
581 meta
= kmalloc(sizeof(*meta
), GFP_KERNEL
);
584 memset(meta
, 0, sizeof(*meta
));
586 memcpy(&meta
->lvalue
.hdr
, &hdr
->left
, sizeof(hdr
->left
));
587 memcpy(&meta
->rvalue
.hdr
, &hdr
->right
, sizeof(hdr
->right
));
589 if (!meta_is_supported(&meta
->lvalue
) ||
590 !meta_is_supported(&meta
->rvalue
)) {
595 if (meta_change_data(&meta
->lvalue
, tb
[TCA_EM_META_LVALUE
-1]) < 0 ||
596 meta_change_data(&meta
->rvalue
, tb
[TCA_EM_META_RVALUE
-1]) < 0)
599 m
->datalen
= sizeof(*meta
);
600 m
->data
= (unsigned long) meta
;
609 static void em_meta_destroy(struct tcf_proto
*tp
, struct tcf_ematch
*m
)
612 meta_delete((struct meta_match
*) m
->data
);
615 static int em_meta_dump(struct sk_buff
*skb
, struct tcf_ematch
*em
)
617 struct meta_match
*meta
= (struct meta_match
*) em
->data
;
618 struct tcf_meta_hdr hdr
;
619 struct meta_type_ops
*ops
;
621 memset(&hdr
, 0, sizeof(hdr
));
622 memcpy(&hdr
.left
, &meta
->lvalue
.hdr
, sizeof(hdr
.left
));
623 memcpy(&hdr
.right
, &meta
->rvalue
.hdr
, sizeof(hdr
.right
));
625 RTA_PUT(skb
, TCA_EM_META_HDR
, sizeof(hdr
), &hdr
);
627 ops
= meta_type_ops(&meta
->lvalue
);
628 if (ops
->dump(skb
, &meta
->lvalue
, TCA_EM_META_LVALUE
) < 0 ||
629 ops
->dump(skb
, &meta
->rvalue
, TCA_EM_META_RVALUE
) < 0)
638 static struct tcf_ematch_ops em_meta_ops
= {
640 .change
= em_meta_change
,
641 .match
= em_meta_match
,
642 .destroy
= em_meta_destroy
,
643 .dump
= em_meta_dump
,
644 .owner
= THIS_MODULE
,
645 .link
= LIST_HEAD_INIT(em_meta_ops
.link
)
648 static int __init
init_em_meta(void)
650 return tcf_em_register(&em_meta_ops
);
653 static void __exit
exit_em_meta(void)
655 tcf_em_unregister(&em_meta_ops
);
658 MODULE_LICENSE("GPL");
660 module_init(init_em_meta
);
661 module_exit(exit_em_meta
);