]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * net/sched/cls_tcindex.c Packet classifier for skb->tc_index | |
3 | * | |
4 | * Written 1998,1999 by Werner Almesberger, EPFL ICA | |
5 | */ | |
6 | ||
1da177e4 LT |
7 | #include <linux/module.h> |
8 | #include <linux/types.h> | |
9 | #include <linux/kernel.h> | |
10 | #include <linux/skbuff.h> | |
11 | #include <linux/errno.h> | |
1da177e4 | 12 | #include <net/act_api.h> |
dc5fc579 | 13 | #include <net/netlink.h> |
1da177e4 | 14 | #include <net/pkt_cls.h> |
1da177e4 LT |
15 | |
16 | ||
17 | /* | |
18 | * Not quite sure if we need all the xchgs Alexey uses when accessing things. | |
19 | * Can always add them later ... :) | |
20 | */ | |
21 | ||
22 | /* | |
23 | * Passing parameters to the root seems to be done more awkwardly than really | |
24 | * necessary. At least, u32 doesn't seem to use such dirty hacks. To be | |
25 | * verified. FIXME. | |
26 | */ | |
27 | ||
28 | #define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */ | |
29 | #define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */ | |
30 | ||
31 | ||
1da177e4 LT |
32 | #define PRIV(tp) ((struct tcindex_data *) (tp)->root) |
33 | ||
34 | ||
35 | struct tcindex_filter_result { | |
36 | struct tcf_exts exts; | |
37 | struct tcf_result res; | |
38 | }; | |
39 | ||
40 | struct tcindex_filter { | |
41 | u16 key; | |
42 | struct tcindex_filter_result result; | |
43 | struct tcindex_filter *next; | |
44 | }; | |
45 | ||
46 | ||
47 | struct tcindex_data { | |
48 | struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */ | |
49 | struct tcindex_filter **h; /* imperfect hash; only used if !perfect; | |
50 | NULL if unused */ | |
51 | u16 mask; /* AND key with mask */ | |
52 | int shift; /* shift ANDed key to the right */ | |
53 | int hash; /* hash table size; 0 if undefined */ | |
54 | int alloc_hash; /* allocated size */ | |
55 | int fall_through; /* 0: only classify if explicit match */ | |
56 | }; | |
57 | ||
58 | static struct tcf_ext_map tcindex_ext_map = { | |
59 | .police = TCA_TCINDEX_POLICE, | |
60 | .action = TCA_TCINDEX_ACT | |
61 | }; | |
62 | ||
63 | static inline int | |
64 | tcindex_filter_is_set(struct tcindex_filter_result *r) | |
65 | { | |
66 | return tcf_exts_is_predicative(&r->exts) || r->res.classid; | |
67 | } | |
68 | ||
69 | static struct tcindex_filter_result * | |
70 | tcindex_lookup(struct tcindex_data *p, u16 key) | |
71 | { | |
72 | struct tcindex_filter *f; | |
73 | ||
74 | if (p->perfect) | |
75 | return tcindex_filter_is_set(p->perfect + key) ? | |
76 | p->perfect + key : NULL; | |
77 | else if (p->h) { | |
78 | for (f = p->h[key % p->hash]; f; f = f->next) | |
79 | if (f->key == key) | |
80 | return &f->result; | |
81 | } | |
82 | ||
83 | return NULL; | |
84 | } | |
85 | ||
86 | ||
87 | static int tcindex_classify(struct sk_buff *skb, struct tcf_proto *tp, | |
88 | struct tcf_result *res) | |
89 | { | |
90 | struct tcindex_data *p = PRIV(tp); | |
91 | struct tcindex_filter_result *f; | |
92 | int key = (skb->tc_index & p->mask) >> p->shift; | |
93 | ||
aa767bfe SH |
94 | pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n", |
95 | skb, tp, res, p); | |
1da177e4 LT |
96 | |
97 | f = tcindex_lookup(p, key); | |
98 | if (!f) { | |
99 | if (!p->fall_through) | |
100 | return -1; | |
101 | res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key); | |
102 | res->class = 0; | |
aa767bfe | 103 | pr_debug("alg 0x%x\n", res->classid); |
1da177e4 LT |
104 | return 0; |
105 | } | |
106 | *res = f->res; | |
aa767bfe | 107 | pr_debug("map 0x%x\n", res->classid); |
1da177e4 LT |
108 | |
109 | return tcf_exts_exec(skb, &f->exts, res); | |
110 | } | |
111 | ||
112 | ||
113 | static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle) | |
114 | { | |
115 | struct tcindex_data *p = PRIV(tp); | |
116 | struct tcindex_filter_result *r; | |
117 | ||
aa767bfe | 118 | pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle); |
1da177e4 LT |
119 | if (p->perfect && handle >= p->alloc_hash) |
120 | return 0; | |
121 | r = tcindex_lookup(p, handle); | |
122 | return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL; | |
123 | } | |
124 | ||
125 | ||
126 | static void tcindex_put(struct tcf_proto *tp, unsigned long f) | |
127 | { | |
aa767bfe | 128 | pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f); |
1da177e4 LT |
129 | } |
130 | ||
131 | ||
132 | static int tcindex_init(struct tcf_proto *tp) | |
133 | { | |
134 | struct tcindex_data *p; | |
135 | ||
aa767bfe SH |
136 | pr_debug("tcindex_init(tp %p)\n", tp); |
137 | p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL); | |
1da177e4 LT |
138 | if (!p) |
139 | return -ENOMEM; | |
140 | ||
1da177e4 LT |
141 | p->mask = 0xffff; |
142 | p->hash = DEFAULT_HASH_SIZE; | |
143 | p->fall_through = 1; | |
144 | ||
145 | tp->root = p; | |
146 | return 0; | |
147 | } | |
148 | ||
149 | ||
150 | static int | |
151 | __tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock) | |
152 | { | |
153 | struct tcindex_data *p = PRIV(tp); | |
154 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg; | |
155 | struct tcindex_filter *f = NULL; | |
156 | ||
aa767bfe | 157 | pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f); |
1da177e4 LT |
158 | if (p->perfect) { |
159 | if (!r->res.class) | |
160 | return -ENOENT; | |
161 | } else { | |
162 | int i; | |
163 | struct tcindex_filter **walk = NULL; | |
164 | ||
165 | for (i = 0; i < p->hash; i++) | |
166 | for (walk = p->h+i; *walk; walk = &(*walk)->next) | |
167 | if (&(*walk)->result == r) | |
168 | goto found; | |
169 | return -ENOENT; | |
170 | ||
171 | found: | |
172 | f = *walk; | |
173 | if (lock) | |
174 | tcf_tree_lock(tp); | |
175 | *walk = f->next; | |
176 | if (lock) | |
177 | tcf_tree_unlock(tp); | |
178 | } | |
179 | tcf_unbind_filter(tp, &r->res); | |
180 | tcf_exts_destroy(tp, &r->exts); | |
a51482bd | 181 | kfree(f); |
1da177e4 LT |
182 | return 0; |
183 | } | |
184 | ||
185 | static int tcindex_delete(struct tcf_proto *tp, unsigned long arg) | |
186 | { | |
187 | return __tcindex_delete(tp, arg, 1); | |
188 | } | |
189 | ||
190 | static inline int | |
191 | valid_perfect_hash(struct tcindex_data *p) | |
192 | { | |
193 | return p->hash > (p->mask >> p->shift); | |
194 | } | |
195 | ||
196 | static int | |
197 | tcindex_set_parms(struct tcf_proto *tp, unsigned long base, u32 handle, | |
198 | struct tcindex_data *p, struct tcindex_filter_result *r, | |
add93b61 | 199 | struct nlattr **tb, struct nlattr *est) |
1da177e4 LT |
200 | { |
201 | int err, balloc = 0; | |
202 | struct tcindex_filter_result new_filter_result, *old_r = r; | |
203 | struct tcindex_filter_result cr; | |
204 | struct tcindex_data cp; | |
205 | struct tcindex_filter *f = NULL; /* make gcc behave */ | |
206 | struct tcf_exts e; | |
207 | ||
208 | err = tcf_exts_validate(tp, tb, est, &e, &tcindex_ext_map); | |
209 | if (err < 0) | |
210 | return err; | |
10297b99 | 211 | |
1da177e4 LT |
212 | memcpy(&cp, p, sizeof(cp)); |
213 | memset(&new_filter_result, 0, sizeof(new_filter_result)); | |
214 | ||
215 | if (old_r) | |
216 | memcpy(&cr, r, sizeof(cr)); | |
217 | else | |
218 | memset(&cr, 0, sizeof(cr)); | |
219 | ||
220 | err = -EINVAL; | |
add93b61 PM |
221 | if (tb[TCA_TCINDEX_HASH]) { |
222 | if (nla_len(tb[TCA_TCINDEX_HASH]) < sizeof(u32)) | |
1da177e4 | 223 | goto errout; |
add93b61 | 224 | cp.hash = *(u32 *) nla_data(tb[TCA_TCINDEX_HASH]); |
1da177e4 LT |
225 | } |
226 | ||
add93b61 PM |
227 | if (tb[TCA_TCINDEX_MASK]) { |
228 | if (nla_len(tb[TCA_TCINDEX_MASK]) < sizeof(u16)) | |
1da177e4 | 229 | goto errout; |
add93b61 | 230 | cp.mask = *(u16 *) nla_data(tb[TCA_TCINDEX_MASK]); |
1da177e4 LT |
231 | } |
232 | ||
add93b61 PM |
233 | if (tb[TCA_TCINDEX_SHIFT]) { |
234 | if (nla_len(tb[TCA_TCINDEX_SHIFT]) < sizeof(int)) | |
1da177e4 | 235 | goto errout; |
add93b61 | 236 | cp.shift = *(int *) nla_data(tb[TCA_TCINDEX_SHIFT]); |
1da177e4 LT |
237 | } |
238 | ||
239 | err = -EBUSY; | |
240 | /* Hash already allocated, make sure that we still meet the | |
241 | * requirements for the allocated hash. | |
242 | */ | |
243 | if (cp.perfect) { | |
244 | if (!valid_perfect_hash(&cp) || | |
245 | cp.hash > cp.alloc_hash) | |
246 | goto errout; | |
247 | } else if (cp.h && cp.hash != cp.alloc_hash) | |
248 | goto errout; | |
249 | ||
250 | err = -EINVAL; | |
add93b61 PM |
251 | if (tb[TCA_TCINDEX_FALL_THROUGH]) { |
252 | if (nla_len(tb[TCA_TCINDEX_FALL_THROUGH]) < sizeof(u32)) | |
1da177e4 LT |
253 | goto errout; |
254 | cp.fall_through = | |
add93b61 | 255 | *(u32 *) nla_data(tb[TCA_TCINDEX_FALL_THROUGH]); |
1da177e4 LT |
256 | } |
257 | ||
258 | if (!cp.hash) { | |
259 | /* Hash not specified, use perfect hash if the upper limit | |
260 | * of the hashing index is below the threshold. | |
261 | */ | |
262 | if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD) | |
263 | cp.hash = (cp.mask >> cp.shift)+1; | |
264 | else | |
265 | cp.hash = DEFAULT_HASH_SIZE; | |
266 | } | |
267 | ||
268 | if (!cp.perfect && !cp.h) | |
269 | cp.alloc_hash = cp.hash; | |
270 | ||
271 | /* Note: this could be as restrictive as if (handle & ~(mask >> shift)) | |
272 | * but then, we'd fail handles that may become valid after some future | |
273 | * mask change. While this is extremely unlikely to ever matter, | |
274 | * the check below is safer (and also more backwards-compatible). | |
275 | */ | |
276 | if (cp.perfect || valid_perfect_hash(&cp)) | |
277 | if (handle >= cp.alloc_hash) | |
278 | goto errout; | |
279 | ||
280 | ||
281 | err = -ENOMEM; | |
282 | if (!cp.perfect && !cp.h) { | |
283 | if (valid_perfect_hash(&cp)) { | |
0da974f4 | 284 | cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL); |
1da177e4 LT |
285 | if (!cp.perfect) |
286 | goto errout; | |
1da177e4 LT |
287 | balloc = 1; |
288 | } else { | |
0da974f4 | 289 | cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL); |
1da177e4 LT |
290 | if (!cp.h) |
291 | goto errout; | |
1da177e4 LT |
292 | balloc = 2; |
293 | } | |
294 | } | |
295 | ||
296 | if (cp.perfect) | |
297 | r = cp.perfect + handle; | |
298 | else | |
299 | r = tcindex_lookup(&cp, handle) ? : &new_filter_result; | |
300 | ||
301 | if (r == &new_filter_result) { | |
0da974f4 | 302 | f = kzalloc(sizeof(*f), GFP_KERNEL); |
1da177e4 LT |
303 | if (!f) |
304 | goto errout_alloc; | |
10297b99 | 305 | } |
1da177e4 | 306 | |
add93b61 PM |
307 | if (tb[TCA_TCINDEX_CLASSID]) { |
308 | cr.res.classid = *(u32 *) nla_data(tb[TCA_TCINDEX_CLASSID]); | |
1da177e4 | 309 | tcf_bind_filter(tp, &cr.res, base); |
10297b99 | 310 | } |
1da177e4 LT |
311 | |
312 | tcf_exts_change(tp, &cr.exts, &e); | |
313 | ||
314 | tcf_tree_lock(tp); | |
315 | if (old_r && old_r != r) | |
316 | memset(old_r, 0, sizeof(*old_r)); | |
317 | ||
318 | memcpy(p, &cp, sizeof(cp)); | |
319 | memcpy(r, &cr, sizeof(cr)); | |
320 | ||
321 | if (r == &new_filter_result) { | |
322 | struct tcindex_filter **fp; | |
323 | ||
324 | f->key = handle; | |
325 | f->result = new_filter_result; | |
326 | f->next = NULL; | |
327 | for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next) | |
328 | /* nothing */; | |
329 | *fp = f; | |
10297b99 | 330 | } |
1da177e4 LT |
331 | tcf_tree_unlock(tp); |
332 | ||
333 | return 0; | |
334 | ||
335 | errout_alloc: | |
336 | if (balloc == 1) | |
337 | kfree(cp.perfect); | |
338 | else if (balloc == 2) | |
339 | kfree(cp.h); | |
340 | errout: | |
341 | tcf_exts_destroy(tp, &e); | |
342 | return err; | |
343 | } | |
344 | ||
345 | static int | |
346 | tcindex_change(struct tcf_proto *tp, unsigned long base, u32 handle, | |
add93b61 | 347 | struct nlattr **tca, unsigned long *arg) |
1da177e4 | 348 | { |
add93b61 PM |
349 | struct nlattr *opt = tca[TCA_OPTIONS]; |
350 | struct nlattr *tb[TCA_TCINDEX_MAX + 1]; | |
1da177e4 LT |
351 | struct tcindex_data *p = PRIV(tp); |
352 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg; | |
cee63723 | 353 | int err; |
1da177e4 | 354 | |
aa767bfe | 355 | pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p," |
1da177e4 LT |
356 | "p %p,r %p,*arg 0x%lx\n", |
357 | tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L); | |
358 | ||
359 | if (!opt) | |
360 | return 0; | |
361 | ||
cee63723 PM |
362 | err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, NULL); |
363 | if (err < 0) | |
364 | return err; | |
1da177e4 | 365 | |
add93b61 | 366 | return tcindex_set_parms(tp, base, handle, p, r, tb, tca[TCA_RATE]); |
1da177e4 LT |
367 | } |
368 | ||
369 | ||
370 | static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker) | |
371 | { | |
372 | struct tcindex_data *p = PRIV(tp); | |
aa767bfe | 373 | struct tcindex_filter *f, *next; |
1da177e4 LT |
374 | int i; |
375 | ||
aa767bfe | 376 | pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p); |
1da177e4 LT |
377 | if (p->perfect) { |
378 | for (i = 0; i < p->hash; i++) { | |
379 | if (!p->perfect[i].res.class) | |
380 | continue; | |
381 | if (walker->count >= walker->skip) { | |
382 | if (walker->fn(tp, | |
383 | (unsigned long) (p->perfect+i), walker) | |
384 | < 0) { | |
385 | walker->stop = 1; | |
386 | return; | |
387 | } | |
388 | } | |
389 | walker->count++; | |
390 | } | |
391 | } | |
392 | if (!p->h) | |
393 | return; | |
394 | for (i = 0; i < p->hash; i++) { | |
395 | for (f = p->h[i]; f; f = next) { | |
396 | next = f->next; | |
397 | if (walker->count >= walker->skip) { | |
aa767bfe | 398 | if (walker->fn(tp, (unsigned long) &f->result, |
1da177e4 LT |
399 | walker) < 0) { |
400 | walker->stop = 1; | |
401 | return; | |
402 | } | |
403 | } | |
404 | walker->count++; | |
405 | } | |
406 | } | |
407 | } | |
408 | ||
409 | ||
410 | static int tcindex_destroy_element(struct tcf_proto *tp, | |
411 | unsigned long arg, struct tcf_walker *walker) | |
412 | { | |
413 | return __tcindex_delete(tp, arg, 0); | |
414 | } | |
415 | ||
416 | ||
417 | static void tcindex_destroy(struct tcf_proto *tp) | |
418 | { | |
419 | struct tcindex_data *p = PRIV(tp); | |
420 | struct tcf_walker walker; | |
421 | ||
aa767bfe | 422 | pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p); |
1da177e4 LT |
423 | walker.count = 0; |
424 | walker.skip = 0; | |
425 | walker.fn = &tcindex_destroy_element; | |
aa767bfe | 426 | tcindex_walk(tp, &walker); |
a51482bd JJ |
427 | kfree(p->perfect); |
428 | kfree(p->h); | |
1da177e4 LT |
429 | kfree(p); |
430 | tp->root = NULL; | |
431 | } | |
432 | ||
433 | ||
434 | static int tcindex_dump(struct tcf_proto *tp, unsigned long fh, | |
435 | struct sk_buff *skb, struct tcmsg *t) | |
436 | { | |
437 | struct tcindex_data *p = PRIV(tp); | |
438 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh; | |
27a884dc | 439 | unsigned char *b = skb_tail_pointer(skb); |
4b3550ef | 440 | struct nlattr *nest; |
1da177e4 | 441 | |
aa767bfe SH |
442 | pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n", |
443 | tp, fh, skb, t, p, r, b); | |
444 | pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h); | |
4b3550ef PM |
445 | |
446 | nest = nla_nest_start(skb, TCA_OPTIONS); | |
447 | if (nest == NULL) | |
448 | goto nla_put_failure; | |
449 | ||
1da177e4 LT |
450 | if (!fh) { |
451 | t->tcm_handle = ~0; /* whatever ... */ | |
24beeab5 PM |
452 | NLA_PUT_U32(skb, TCA_TCINDEX_HASH, p->hash); |
453 | NLA_PUT_U16(skb, TCA_TCINDEX_MASK, p->mask); | |
454 | NLA_PUT_U32(skb, TCA_TCINDEX_SHIFT, p->shift); | |
455 | NLA_PUT_U32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through); | |
4b3550ef | 456 | nla_nest_end(skb, nest); |
1da177e4 LT |
457 | } else { |
458 | if (p->perfect) { | |
459 | t->tcm_handle = r-p->perfect; | |
460 | } else { | |
461 | struct tcindex_filter *f; | |
462 | int i; | |
463 | ||
464 | t->tcm_handle = 0; | |
465 | for (i = 0; !t->tcm_handle && i < p->hash; i++) { | |
466 | for (f = p->h[i]; !t->tcm_handle && f; | |
467 | f = f->next) { | |
468 | if (&f->result == r) | |
469 | t->tcm_handle = f->key; | |
470 | } | |
471 | } | |
472 | } | |
aa767bfe | 473 | pr_debug("handle = %d\n", t->tcm_handle); |
1da177e4 | 474 | if (r->res.class) |
24beeab5 | 475 | NLA_PUT_U32(skb, TCA_TCINDEX_CLASSID, r->res.classid); |
1da177e4 LT |
476 | |
477 | if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0) | |
add93b61 | 478 | goto nla_put_failure; |
4b3550ef | 479 | nla_nest_end(skb, nest); |
1da177e4 LT |
480 | |
481 | if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0) | |
add93b61 | 482 | goto nla_put_failure; |
1da177e4 | 483 | } |
10297b99 | 484 | |
1da177e4 LT |
485 | return skb->len; |
486 | ||
add93b61 | 487 | nla_put_failure: |
dc5fc579 | 488 | nlmsg_trim(skb, b); |
1da177e4 LT |
489 | return -1; |
490 | } | |
491 | ||
2eb9d75c | 492 | static struct tcf_proto_ops cls_tcindex_ops __read_mostly = { |
1da177e4 LT |
493 | .kind = "tcindex", |
494 | .classify = tcindex_classify, | |
495 | .init = tcindex_init, | |
496 | .destroy = tcindex_destroy, | |
497 | .get = tcindex_get, | |
498 | .put = tcindex_put, | |
499 | .change = tcindex_change, | |
500 | .delete = tcindex_delete, | |
501 | .walk = tcindex_walk, | |
502 | .dump = tcindex_dump, | |
503 | .owner = THIS_MODULE, | |
504 | }; | |
505 | ||
506 | static int __init init_tcindex(void) | |
507 | { | |
508 | return register_tcf_proto_ops(&cls_tcindex_ops); | |
509 | } | |
510 | ||
10297b99 | 511 | static void __exit exit_tcindex(void) |
1da177e4 LT |
512 | { |
513 | unregister_tcf_proto_ops(&cls_tcindex_ops); | |
514 | } | |
515 | ||
516 | module_init(init_tcindex) | |
517 | module_exit(exit_tcindex) | |
518 | MODULE_LICENSE("GPL"); |