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> | |
5a0e3ad6 | 12 | #include <linux/slab.h> |
1da177e4 | 13 | #include <net/act_api.h> |
dc5fc579 | 14 | #include <net/netlink.h> |
1da177e4 | 15 | #include <net/pkt_cls.h> |
1da177e4 | 16 | |
1da177e4 LT |
17 | /* |
18 | * Passing parameters to the root seems to be done more awkwardly than really | |
19 | * necessary. At least, u32 doesn't seem to use such dirty hacks. To be | |
20 | * verified. FIXME. | |
21 | */ | |
22 | ||
23 | #define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */ | |
24 | #define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */ | |
25 | ||
26 | ||
1da177e4 LT |
27 | #define PRIV(tp) ((struct tcindex_data *) (tp)->root) |
28 | ||
29 | ||
30 | struct tcindex_filter_result { | |
31 | struct tcf_exts exts; | |
32 | struct tcf_result res; | |
33 | }; | |
34 | ||
35 | struct tcindex_filter { | |
36 | u16 key; | |
37 | struct tcindex_filter_result result; | |
38 | struct tcindex_filter *next; | |
39 | }; | |
40 | ||
41 | ||
42 | struct tcindex_data { | |
43 | struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */ | |
44 | struct tcindex_filter **h; /* imperfect hash; only used if !perfect; | |
45 | NULL if unused */ | |
46 | u16 mask; /* AND key with mask */ | |
47 | int shift; /* shift ANDed key to the right */ | |
48 | int hash; /* hash table size; 0 if undefined */ | |
49 | int alloc_hash; /* allocated size */ | |
50 | int fall_through; /* 0: only classify if explicit match */ | |
51 | }; | |
52 | ||
5239008b | 53 | static const struct tcf_ext_map tcindex_ext_map = { |
1da177e4 LT |
54 | .police = TCA_TCINDEX_POLICE, |
55 | .action = TCA_TCINDEX_ACT | |
56 | }; | |
57 | ||
58 | static inline int | |
59 | tcindex_filter_is_set(struct tcindex_filter_result *r) | |
60 | { | |
61 | return tcf_exts_is_predicative(&r->exts) || r->res.classid; | |
62 | } | |
63 | ||
64 | static struct tcindex_filter_result * | |
65 | tcindex_lookup(struct tcindex_data *p, u16 key) | |
66 | { | |
67 | struct tcindex_filter *f; | |
68 | ||
69 | if (p->perfect) | |
70 | return tcindex_filter_is_set(p->perfect + key) ? | |
71 | p->perfect + key : NULL; | |
72 | else if (p->h) { | |
73 | for (f = p->h[key % p->hash]; f; f = f->next) | |
74 | if (f->key == key) | |
75 | return &f->result; | |
76 | } | |
77 | ||
78 | return NULL; | |
79 | } | |
80 | ||
81 | ||
dc7f9f6e | 82 | static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp, |
1da177e4 LT |
83 | struct tcf_result *res) |
84 | { | |
85 | struct tcindex_data *p = PRIV(tp); | |
86 | struct tcindex_filter_result *f; | |
87 | int key = (skb->tc_index & p->mask) >> p->shift; | |
88 | ||
aa767bfe SH |
89 | pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n", |
90 | skb, tp, res, p); | |
1da177e4 LT |
91 | |
92 | f = tcindex_lookup(p, key); | |
93 | if (!f) { | |
94 | if (!p->fall_through) | |
95 | return -1; | |
96 | res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key); | |
97 | res->class = 0; | |
aa767bfe | 98 | pr_debug("alg 0x%x\n", res->classid); |
1da177e4 LT |
99 | return 0; |
100 | } | |
101 | *res = f->res; | |
aa767bfe | 102 | pr_debug("map 0x%x\n", res->classid); |
1da177e4 LT |
103 | |
104 | return tcf_exts_exec(skb, &f->exts, res); | |
105 | } | |
106 | ||
107 | ||
108 | static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle) | |
109 | { | |
110 | struct tcindex_data *p = PRIV(tp); | |
111 | struct tcindex_filter_result *r; | |
112 | ||
aa767bfe | 113 | pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle); |
1da177e4 LT |
114 | if (p->perfect && handle >= p->alloc_hash) |
115 | return 0; | |
116 | r = tcindex_lookup(p, handle); | |
117 | return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL; | |
118 | } | |
119 | ||
120 | ||
121 | static void tcindex_put(struct tcf_proto *tp, unsigned long f) | |
122 | { | |
aa767bfe | 123 | pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f); |
1da177e4 LT |
124 | } |
125 | ||
126 | ||
127 | static int tcindex_init(struct tcf_proto *tp) | |
128 | { | |
129 | struct tcindex_data *p; | |
130 | ||
aa767bfe SH |
131 | pr_debug("tcindex_init(tp %p)\n", tp); |
132 | p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL); | |
1da177e4 LT |
133 | if (!p) |
134 | return -ENOMEM; | |
135 | ||
1da177e4 LT |
136 | p->mask = 0xffff; |
137 | p->hash = DEFAULT_HASH_SIZE; | |
138 | p->fall_through = 1; | |
139 | ||
140 | tp->root = p; | |
141 | return 0; | |
142 | } | |
143 | ||
144 | ||
145 | static int | |
146 | __tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock) | |
147 | { | |
148 | struct tcindex_data *p = PRIV(tp); | |
149 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg; | |
150 | struct tcindex_filter *f = NULL; | |
151 | ||
aa767bfe | 152 | pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f); |
1da177e4 LT |
153 | if (p->perfect) { |
154 | if (!r->res.class) | |
155 | return -ENOENT; | |
156 | } else { | |
157 | int i; | |
158 | struct tcindex_filter **walk = NULL; | |
159 | ||
160 | for (i = 0; i < p->hash; i++) | |
161 | for (walk = p->h+i; *walk; walk = &(*walk)->next) | |
162 | if (&(*walk)->result == r) | |
163 | goto found; | |
164 | return -ENOENT; | |
165 | ||
166 | found: | |
167 | f = *walk; | |
168 | if (lock) | |
169 | tcf_tree_lock(tp); | |
170 | *walk = f->next; | |
171 | if (lock) | |
172 | tcf_tree_unlock(tp); | |
173 | } | |
174 | tcf_unbind_filter(tp, &r->res); | |
175 | tcf_exts_destroy(tp, &r->exts); | |
a51482bd | 176 | kfree(f); |
1da177e4 LT |
177 | return 0; |
178 | } | |
179 | ||
180 | static int tcindex_delete(struct tcf_proto *tp, unsigned long arg) | |
181 | { | |
182 | return __tcindex_delete(tp, arg, 1); | |
183 | } | |
184 | ||
185 | static inline int | |
186 | valid_perfect_hash(struct tcindex_data *p) | |
187 | { | |
188 | return p->hash > (p->mask >> p->shift); | |
189 | } | |
190 | ||
6fa8c014 PM |
191 | static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = { |
192 | [TCA_TCINDEX_HASH] = { .type = NLA_U32 }, | |
193 | [TCA_TCINDEX_MASK] = { .type = NLA_U16 }, | |
194 | [TCA_TCINDEX_SHIFT] = { .type = NLA_U32 }, | |
195 | [TCA_TCINDEX_FALL_THROUGH] = { .type = NLA_U32 }, | |
196 | [TCA_TCINDEX_CLASSID] = { .type = NLA_U32 }, | |
197 | }; | |
198 | ||
1da177e4 | 199 | static int |
c1b52739 BL |
200 | tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, |
201 | u32 handle, struct tcindex_data *p, | |
202 | struct tcindex_filter_result *r, struct nlattr **tb, | |
203 | struct nlattr *est) | |
1da177e4 LT |
204 | { |
205 | int err, balloc = 0; | |
206 | struct tcindex_filter_result new_filter_result, *old_r = r; | |
207 | struct tcindex_filter_result cr; | |
208 | struct tcindex_data cp; | |
209 | struct tcindex_filter *f = NULL; /* make gcc behave */ | |
210 | struct tcf_exts e; | |
211 | ||
c1b52739 | 212 | err = tcf_exts_validate(net, tp, tb, est, &e, &tcindex_ext_map); |
1da177e4 LT |
213 | if (err < 0) |
214 | return err; | |
10297b99 | 215 | |
1da177e4 LT |
216 | memcpy(&cp, p, sizeof(cp)); |
217 | memset(&new_filter_result, 0, sizeof(new_filter_result)); | |
218 | ||
219 | if (old_r) | |
220 | memcpy(&cr, r, sizeof(cr)); | |
221 | else | |
222 | memset(&cr, 0, sizeof(cr)); | |
223 | ||
6fa8c014 | 224 | if (tb[TCA_TCINDEX_HASH]) |
1587bac4 | 225 | cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]); |
1da177e4 | 226 | |
6fa8c014 | 227 | if (tb[TCA_TCINDEX_MASK]) |
1587bac4 | 228 | cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]); |
1da177e4 | 229 | |
6fa8c014 | 230 | if (tb[TCA_TCINDEX_SHIFT]) |
1587bac4 | 231 | cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]); |
1da177e4 LT |
232 | |
233 | err = -EBUSY; | |
234 | /* Hash already allocated, make sure that we still meet the | |
235 | * requirements for the allocated hash. | |
236 | */ | |
237 | if (cp.perfect) { | |
238 | if (!valid_perfect_hash(&cp) || | |
239 | cp.hash > cp.alloc_hash) | |
240 | goto errout; | |
241 | } else if (cp.h && cp.hash != cp.alloc_hash) | |
242 | goto errout; | |
243 | ||
244 | err = -EINVAL; | |
6fa8c014 | 245 | if (tb[TCA_TCINDEX_FALL_THROUGH]) |
1587bac4 | 246 | cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]); |
1da177e4 LT |
247 | |
248 | if (!cp.hash) { | |
249 | /* Hash not specified, use perfect hash if the upper limit | |
250 | * of the hashing index is below the threshold. | |
251 | */ | |
252 | if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD) | |
cc7ec456 | 253 | cp.hash = (cp.mask >> cp.shift) + 1; |
1da177e4 LT |
254 | else |
255 | cp.hash = DEFAULT_HASH_SIZE; | |
256 | } | |
257 | ||
258 | if (!cp.perfect && !cp.h) | |
259 | cp.alloc_hash = cp.hash; | |
260 | ||
261 | /* Note: this could be as restrictive as if (handle & ~(mask >> shift)) | |
262 | * but then, we'd fail handles that may become valid after some future | |
263 | * mask change. While this is extremely unlikely to ever matter, | |
264 | * the check below is safer (and also more backwards-compatible). | |
265 | */ | |
266 | if (cp.perfect || valid_perfect_hash(&cp)) | |
267 | if (handle >= cp.alloc_hash) | |
268 | goto errout; | |
269 | ||
270 | ||
271 | err = -ENOMEM; | |
272 | if (!cp.perfect && !cp.h) { | |
273 | if (valid_perfect_hash(&cp)) { | |
0da974f4 | 274 | cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL); |
1da177e4 LT |
275 | if (!cp.perfect) |
276 | goto errout; | |
1da177e4 LT |
277 | balloc = 1; |
278 | } else { | |
0da974f4 | 279 | cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL); |
1da177e4 LT |
280 | if (!cp.h) |
281 | goto errout; | |
1da177e4 LT |
282 | balloc = 2; |
283 | } | |
284 | } | |
285 | ||
286 | if (cp.perfect) | |
287 | r = cp.perfect + handle; | |
288 | else | |
289 | r = tcindex_lookup(&cp, handle) ? : &new_filter_result; | |
290 | ||
291 | if (r == &new_filter_result) { | |
0da974f4 | 292 | f = kzalloc(sizeof(*f), GFP_KERNEL); |
1da177e4 LT |
293 | if (!f) |
294 | goto errout_alloc; | |
10297b99 | 295 | } |
1da177e4 | 296 | |
add93b61 | 297 | if (tb[TCA_TCINDEX_CLASSID]) { |
1587bac4 | 298 | cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]); |
1da177e4 | 299 | tcf_bind_filter(tp, &cr.res, base); |
10297b99 | 300 | } |
1da177e4 LT |
301 | |
302 | tcf_exts_change(tp, &cr.exts, &e); | |
303 | ||
304 | tcf_tree_lock(tp); | |
305 | if (old_r && old_r != r) | |
306 | memset(old_r, 0, sizeof(*old_r)); | |
307 | ||
308 | memcpy(p, &cp, sizeof(cp)); | |
309 | memcpy(r, &cr, sizeof(cr)); | |
310 | ||
311 | if (r == &new_filter_result) { | |
312 | struct tcindex_filter **fp; | |
313 | ||
314 | f->key = handle; | |
315 | f->result = new_filter_result; | |
316 | f->next = NULL; | |
317 | for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next) | |
318 | /* nothing */; | |
319 | *fp = f; | |
10297b99 | 320 | } |
1da177e4 LT |
321 | tcf_tree_unlock(tp); |
322 | ||
323 | return 0; | |
324 | ||
325 | errout_alloc: | |
326 | if (balloc == 1) | |
327 | kfree(cp.perfect); | |
328 | else if (balloc == 2) | |
329 | kfree(cp.h); | |
330 | errout: | |
331 | tcf_exts_destroy(tp, &e); | |
332 | return err; | |
333 | } | |
334 | ||
335 | static int | |
c1b52739 | 336 | tcindex_change(struct net *net, struct sk_buff *in_skb, |
af4c6641 | 337 | struct tcf_proto *tp, unsigned long base, u32 handle, |
add93b61 | 338 | struct nlattr **tca, unsigned long *arg) |
1da177e4 | 339 | { |
add93b61 PM |
340 | struct nlattr *opt = tca[TCA_OPTIONS]; |
341 | struct nlattr *tb[TCA_TCINDEX_MAX + 1]; | |
1da177e4 LT |
342 | struct tcindex_data *p = PRIV(tp); |
343 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg; | |
cee63723 | 344 | int err; |
1da177e4 | 345 | |
aa767bfe | 346 | pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p," |
1da177e4 LT |
347 | "p %p,r %p,*arg 0x%lx\n", |
348 | tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L); | |
349 | ||
350 | if (!opt) | |
351 | return 0; | |
352 | ||
6fa8c014 | 353 | err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy); |
cee63723 PM |
354 | if (err < 0) |
355 | return err; | |
1da177e4 | 356 | |
c1b52739 BL |
357 | return tcindex_set_parms(net, tp, base, handle, p, r, tb, |
358 | tca[TCA_RATE]); | |
1da177e4 LT |
359 | } |
360 | ||
361 | ||
362 | static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker) | |
363 | { | |
364 | struct tcindex_data *p = PRIV(tp); | |
aa767bfe | 365 | struct tcindex_filter *f, *next; |
1da177e4 LT |
366 | int i; |
367 | ||
aa767bfe | 368 | pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p); |
1da177e4 LT |
369 | if (p->perfect) { |
370 | for (i = 0; i < p->hash; i++) { | |
371 | if (!p->perfect[i].res.class) | |
372 | continue; | |
373 | if (walker->count >= walker->skip) { | |
374 | if (walker->fn(tp, | |
375 | (unsigned long) (p->perfect+i), walker) | |
376 | < 0) { | |
377 | walker->stop = 1; | |
378 | return; | |
379 | } | |
380 | } | |
381 | walker->count++; | |
382 | } | |
383 | } | |
384 | if (!p->h) | |
385 | return; | |
386 | for (i = 0; i < p->hash; i++) { | |
387 | for (f = p->h[i]; f; f = next) { | |
388 | next = f->next; | |
389 | if (walker->count >= walker->skip) { | |
aa767bfe | 390 | if (walker->fn(tp, (unsigned long) &f->result, |
1da177e4 LT |
391 | walker) < 0) { |
392 | walker->stop = 1; | |
393 | return; | |
394 | } | |
395 | } | |
396 | walker->count++; | |
397 | } | |
398 | } | |
399 | } | |
400 | ||
401 | ||
402 | static int tcindex_destroy_element(struct tcf_proto *tp, | |
403 | unsigned long arg, struct tcf_walker *walker) | |
404 | { | |
405 | return __tcindex_delete(tp, arg, 0); | |
406 | } | |
407 | ||
408 | ||
409 | static void tcindex_destroy(struct tcf_proto *tp) | |
410 | { | |
411 | struct tcindex_data *p = PRIV(tp); | |
412 | struct tcf_walker walker; | |
413 | ||
aa767bfe | 414 | pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p); |
1da177e4 LT |
415 | walker.count = 0; |
416 | walker.skip = 0; | |
417 | walker.fn = &tcindex_destroy_element; | |
aa767bfe | 418 | tcindex_walk(tp, &walker); |
a51482bd JJ |
419 | kfree(p->perfect); |
420 | kfree(p->h); | |
1da177e4 LT |
421 | kfree(p); |
422 | tp->root = NULL; | |
423 | } | |
424 | ||
425 | ||
426 | static int tcindex_dump(struct tcf_proto *tp, unsigned long fh, | |
427 | struct sk_buff *skb, struct tcmsg *t) | |
428 | { | |
429 | struct tcindex_data *p = PRIV(tp); | |
430 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh; | |
27a884dc | 431 | unsigned char *b = skb_tail_pointer(skb); |
4b3550ef | 432 | struct nlattr *nest; |
1da177e4 | 433 | |
aa767bfe SH |
434 | pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n", |
435 | tp, fh, skb, t, p, r, b); | |
436 | pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h); | |
4b3550ef PM |
437 | |
438 | nest = nla_nest_start(skb, TCA_OPTIONS); | |
439 | if (nest == NULL) | |
440 | goto nla_put_failure; | |
441 | ||
1da177e4 LT |
442 | if (!fh) { |
443 | t->tcm_handle = ~0; /* whatever ... */ | |
1b34ec43 DM |
444 | if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) || |
445 | nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) || | |
446 | nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) || | |
447 | nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through)) | |
448 | goto nla_put_failure; | |
4b3550ef | 449 | nla_nest_end(skb, nest); |
1da177e4 LT |
450 | } else { |
451 | if (p->perfect) { | |
452 | t->tcm_handle = r-p->perfect; | |
453 | } else { | |
454 | struct tcindex_filter *f; | |
455 | int i; | |
456 | ||
457 | t->tcm_handle = 0; | |
458 | for (i = 0; !t->tcm_handle && i < p->hash; i++) { | |
459 | for (f = p->h[i]; !t->tcm_handle && f; | |
460 | f = f->next) { | |
461 | if (&f->result == r) | |
462 | t->tcm_handle = f->key; | |
463 | } | |
464 | } | |
465 | } | |
aa767bfe | 466 | pr_debug("handle = %d\n", t->tcm_handle); |
1b34ec43 DM |
467 | if (r->res.class && |
468 | nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid)) | |
469 | goto nla_put_failure; | |
1da177e4 LT |
470 | |
471 | if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0) | |
add93b61 | 472 | goto nla_put_failure; |
4b3550ef | 473 | nla_nest_end(skb, nest); |
1da177e4 LT |
474 | |
475 | if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0) | |
add93b61 | 476 | goto nla_put_failure; |
1da177e4 | 477 | } |
10297b99 | 478 | |
1da177e4 LT |
479 | return skb->len; |
480 | ||
add93b61 | 481 | nla_put_failure: |
dc5fc579 | 482 | nlmsg_trim(skb, b); |
1da177e4 LT |
483 | return -1; |
484 | } | |
485 | ||
2eb9d75c | 486 | static struct tcf_proto_ops cls_tcindex_ops __read_mostly = { |
1da177e4 LT |
487 | .kind = "tcindex", |
488 | .classify = tcindex_classify, | |
489 | .init = tcindex_init, | |
490 | .destroy = tcindex_destroy, | |
491 | .get = tcindex_get, | |
492 | .put = tcindex_put, | |
493 | .change = tcindex_change, | |
494 | .delete = tcindex_delete, | |
495 | .walk = tcindex_walk, | |
496 | .dump = tcindex_dump, | |
497 | .owner = THIS_MODULE, | |
498 | }; | |
499 | ||
500 | static int __init init_tcindex(void) | |
501 | { | |
502 | return register_tcf_proto_ops(&cls_tcindex_ops); | |
503 | } | |
504 | ||
10297b99 | 505 | static void __exit exit_tcindex(void) |
1da177e4 LT |
506 | { |
507 | unregister_tcf_proto_ops(&cls_tcindex_ops); | |
508 | } | |
509 | ||
510 | module_init(init_tcindex) | |
511 | module_exit(exit_tcindex) | |
512 | MODULE_LICENSE("GPL"); |