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 | struct tcindex_filter_result { |
28 | struct tcf_exts exts; | |
29 | struct tcf_result res; | |
30 | }; | |
31 | ||
32 | struct tcindex_filter { | |
33 | u16 key; | |
34 | struct tcindex_filter_result result; | |
35 | struct tcindex_filter *next; | |
36 | }; | |
37 | ||
38 | ||
39 | struct tcindex_data { | |
40 | struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */ | |
41 | struct tcindex_filter **h; /* imperfect hash; only used if !perfect; | |
42 | NULL if unused */ | |
43 | u16 mask; /* AND key with mask */ | |
44 | int shift; /* shift ANDed key to the right */ | |
45 | int hash; /* hash table size; 0 if undefined */ | |
46 | int alloc_hash; /* allocated size */ | |
47 | int fall_through; /* 0: only classify if explicit match */ | |
48 | }; | |
49 | ||
1da177e4 LT |
50 | static inline int |
51 | tcindex_filter_is_set(struct tcindex_filter_result *r) | |
52 | { | |
53 | return tcf_exts_is_predicative(&r->exts) || r->res.classid; | |
54 | } | |
55 | ||
56 | static struct tcindex_filter_result * | |
57 | tcindex_lookup(struct tcindex_data *p, u16 key) | |
58 | { | |
59 | struct tcindex_filter *f; | |
60 | ||
61 | if (p->perfect) | |
62 | return tcindex_filter_is_set(p->perfect + key) ? | |
63 | p->perfect + key : NULL; | |
64 | else if (p->h) { | |
65 | for (f = p->h[key % p->hash]; f; f = f->next) | |
66 | if (f->key == key) | |
67 | return &f->result; | |
68 | } | |
69 | ||
70 | return NULL; | |
71 | } | |
72 | ||
73 | ||
dc7f9f6e | 74 | static int tcindex_classify(struct sk_buff *skb, const struct tcf_proto *tp, |
1da177e4 LT |
75 | struct tcf_result *res) |
76 | { | |
a8701a6c | 77 | struct tcindex_data *p = tp->root; |
1da177e4 LT |
78 | struct tcindex_filter_result *f; |
79 | int key = (skb->tc_index & p->mask) >> p->shift; | |
80 | ||
aa767bfe SH |
81 | pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n", |
82 | skb, tp, res, p); | |
1da177e4 LT |
83 | |
84 | f = tcindex_lookup(p, key); | |
85 | if (!f) { | |
86 | if (!p->fall_through) | |
87 | return -1; | |
88 | res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key); | |
89 | res->class = 0; | |
aa767bfe | 90 | pr_debug("alg 0x%x\n", res->classid); |
1da177e4 LT |
91 | return 0; |
92 | } | |
93 | *res = f->res; | |
aa767bfe | 94 | pr_debug("map 0x%x\n", res->classid); |
1da177e4 LT |
95 | |
96 | return tcf_exts_exec(skb, &f->exts, res); | |
97 | } | |
98 | ||
99 | ||
100 | static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle) | |
101 | { | |
a8701a6c | 102 | struct tcindex_data *p = tp->root; |
1da177e4 LT |
103 | struct tcindex_filter_result *r; |
104 | ||
aa767bfe | 105 | pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle); |
1da177e4 LT |
106 | if (p->perfect && handle >= p->alloc_hash) |
107 | return 0; | |
108 | r = tcindex_lookup(p, handle); | |
109 | return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL; | |
110 | } | |
111 | ||
112 | ||
113 | static void tcindex_put(struct tcf_proto *tp, unsigned long f) | |
114 | { | |
aa767bfe | 115 | pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f); |
1da177e4 LT |
116 | } |
117 | ||
118 | ||
119 | static int tcindex_init(struct tcf_proto *tp) | |
120 | { | |
121 | struct tcindex_data *p; | |
122 | ||
aa767bfe SH |
123 | pr_debug("tcindex_init(tp %p)\n", tp); |
124 | p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL); | |
1da177e4 LT |
125 | if (!p) |
126 | return -ENOMEM; | |
127 | ||
1da177e4 LT |
128 | p->mask = 0xffff; |
129 | p->hash = DEFAULT_HASH_SIZE; | |
130 | p->fall_through = 1; | |
131 | ||
132 | tp->root = p; | |
133 | return 0; | |
134 | } | |
135 | ||
136 | ||
137 | static int | |
138 | __tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock) | |
139 | { | |
a8701a6c | 140 | struct tcindex_data *p = tp->root; |
1da177e4 LT |
141 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg; |
142 | struct tcindex_filter *f = NULL; | |
143 | ||
aa767bfe | 144 | pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f); |
1da177e4 LT |
145 | if (p->perfect) { |
146 | if (!r->res.class) | |
147 | return -ENOENT; | |
148 | } else { | |
149 | int i; | |
150 | struct tcindex_filter **walk = NULL; | |
151 | ||
152 | for (i = 0; i < p->hash; i++) | |
153 | for (walk = p->h+i; *walk; walk = &(*walk)->next) | |
154 | if (&(*walk)->result == r) | |
155 | goto found; | |
156 | return -ENOENT; | |
157 | ||
158 | found: | |
159 | f = *walk; | |
160 | if (lock) | |
161 | tcf_tree_lock(tp); | |
162 | *walk = f->next; | |
163 | if (lock) | |
164 | tcf_tree_unlock(tp); | |
165 | } | |
166 | tcf_unbind_filter(tp, &r->res); | |
167 | tcf_exts_destroy(tp, &r->exts); | |
a51482bd | 168 | kfree(f); |
1da177e4 LT |
169 | return 0; |
170 | } | |
171 | ||
172 | static int tcindex_delete(struct tcf_proto *tp, unsigned long arg) | |
173 | { | |
174 | return __tcindex_delete(tp, arg, 1); | |
175 | } | |
176 | ||
177 | static inline int | |
178 | valid_perfect_hash(struct tcindex_data *p) | |
179 | { | |
180 | return p->hash > (p->mask >> p->shift); | |
181 | } | |
182 | ||
6fa8c014 PM |
183 | static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = { |
184 | [TCA_TCINDEX_HASH] = { .type = NLA_U32 }, | |
185 | [TCA_TCINDEX_MASK] = { .type = NLA_U16 }, | |
186 | [TCA_TCINDEX_SHIFT] = { .type = NLA_U32 }, | |
187 | [TCA_TCINDEX_FALL_THROUGH] = { .type = NLA_U32 }, | |
188 | [TCA_TCINDEX_CLASSID] = { .type = NLA_U32 }, | |
189 | }; | |
190 | ||
1da177e4 | 191 | static int |
c1b52739 BL |
192 | tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base, |
193 | u32 handle, struct tcindex_data *p, | |
194 | struct tcindex_filter_result *r, struct nlattr **tb, | |
195 | struct nlattr *est) | |
1da177e4 LT |
196 | { |
197 | int err, balloc = 0; | |
198 | struct tcindex_filter_result new_filter_result, *old_r = r; | |
199 | struct tcindex_filter_result cr; | |
200 | struct tcindex_data cp; | |
201 | struct tcindex_filter *f = NULL; /* make gcc behave */ | |
202 | struct tcf_exts e; | |
203 | ||
5da57f42 WC |
204 | tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE); |
205 | err = tcf_exts_validate(net, tp, tb, est, &e); | |
1da177e4 LT |
206 | if (err < 0) |
207 | return err; | |
10297b99 | 208 | |
1da177e4 LT |
209 | memcpy(&cp, p, sizeof(cp)); |
210 | memset(&new_filter_result, 0, sizeof(new_filter_result)); | |
5da57f42 | 211 | tcf_exts_init(&new_filter_result.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE); |
1da177e4 LT |
212 | |
213 | if (old_r) | |
214 | memcpy(&cr, r, sizeof(cr)); | |
33be6271 | 215 | else { |
1da177e4 | 216 | memset(&cr, 0, sizeof(cr)); |
5da57f42 | 217 | tcf_exts_init(&cr.exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE); |
33be6271 | 218 | } |
1da177e4 | 219 | |
6fa8c014 | 220 | if (tb[TCA_TCINDEX_HASH]) |
1587bac4 | 221 | cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]); |
1da177e4 | 222 | |
6fa8c014 | 223 | if (tb[TCA_TCINDEX_MASK]) |
1587bac4 | 224 | cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]); |
1da177e4 | 225 | |
6fa8c014 | 226 | if (tb[TCA_TCINDEX_SHIFT]) |
1587bac4 | 227 | cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]); |
1da177e4 LT |
228 | |
229 | err = -EBUSY; | |
230 | /* Hash already allocated, make sure that we still meet the | |
231 | * requirements for the allocated hash. | |
232 | */ | |
233 | if (cp.perfect) { | |
234 | if (!valid_perfect_hash(&cp) || | |
235 | cp.hash > cp.alloc_hash) | |
236 | goto errout; | |
237 | } else if (cp.h && cp.hash != cp.alloc_hash) | |
238 | goto errout; | |
239 | ||
240 | err = -EINVAL; | |
6fa8c014 | 241 | if (tb[TCA_TCINDEX_FALL_THROUGH]) |
1587bac4 | 242 | cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]); |
1da177e4 LT |
243 | |
244 | if (!cp.hash) { | |
245 | /* Hash not specified, use perfect hash if the upper limit | |
246 | * of the hashing index is below the threshold. | |
247 | */ | |
248 | if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD) | |
cc7ec456 | 249 | cp.hash = (cp.mask >> cp.shift) + 1; |
1da177e4 LT |
250 | else |
251 | cp.hash = DEFAULT_HASH_SIZE; | |
252 | } | |
253 | ||
254 | if (!cp.perfect && !cp.h) | |
255 | cp.alloc_hash = cp.hash; | |
256 | ||
257 | /* Note: this could be as restrictive as if (handle & ~(mask >> shift)) | |
258 | * but then, we'd fail handles that may become valid after some future | |
259 | * mask change. While this is extremely unlikely to ever matter, | |
260 | * the check below is safer (and also more backwards-compatible). | |
261 | */ | |
262 | if (cp.perfect || valid_perfect_hash(&cp)) | |
263 | if (handle >= cp.alloc_hash) | |
264 | goto errout; | |
265 | ||
266 | ||
267 | err = -ENOMEM; | |
268 | if (!cp.perfect && !cp.h) { | |
269 | if (valid_perfect_hash(&cp)) { | |
0da974f4 | 270 | cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL); |
1da177e4 LT |
271 | if (!cp.perfect) |
272 | goto errout; | |
1da177e4 LT |
273 | balloc = 1; |
274 | } else { | |
0da974f4 | 275 | cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL); |
1da177e4 LT |
276 | if (!cp.h) |
277 | goto errout; | |
1da177e4 LT |
278 | balloc = 2; |
279 | } | |
280 | } | |
281 | ||
282 | if (cp.perfect) | |
283 | r = cp.perfect + handle; | |
284 | else | |
285 | r = tcindex_lookup(&cp, handle) ? : &new_filter_result; | |
286 | ||
287 | if (r == &new_filter_result) { | |
0da974f4 | 288 | f = kzalloc(sizeof(*f), GFP_KERNEL); |
1da177e4 LT |
289 | if (!f) |
290 | goto errout_alloc; | |
10297b99 | 291 | } |
1da177e4 | 292 | |
add93b61 | 293 | if (tb[TCA_TCINDEX_CLASSID]) { |
1587bac4 | 294 | cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]); |
1da177e4 | 295 | tcf_bind_filter(tp, &cr.res, base); |
10297b99 | 296 | } |
1da177e4 LT |
297 | |
298 | tcf_exts_change(tp, &cr.exts, &e); | |
299 | ||
300 | tcf_tree_lock(tp); | |
301 | if (old_r && old_r != r) | |
302 | memset(old_r, 0, sizeof(*old_r)); | |
303 | ||
304 | memcpy(p, &cp, sizeof(cp)); | |
305 | memcpy(r, &cr, sizeof(cr)); | |
306 | ||
307 | if (r == &new_filter_result) { | |
308 | struct tcindex_filter **fp; | |
309 | ||
310 | f->key = handle; | |
311 | f->result = new_filter_result; | |
312 | f->next = NULL; | |
313 | for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next) | |
314 | /* nothing */; | |
315 | *fp = f; | |
10297b99 | 316 | } |
1da177e4 LT |
317 | tcf_tree_unlock(tp); |
318 | ||
319 | return 0; | |
320 | ||
321 | errout_alloc: | |
322 | if (balloc == 1) | |
323 | kfree(cp.perfect); | |
324 | else if (balloc == 2) | |
325 | kfree(cp.h); | |
326 | errout: | |
327 | tcf_exts_destroy(tp, &e); | |
328 | return err; | |
329 | } | |
330 | ||
331 | static int | |
c1b52739 | 332 | tcindex_change(struct net *net, struct sk_buff *in_skb, |
af4c6641 | 333 | struct tcf_proto *tp, unsigned long base, u32 handle, |
add93b61 | 334 | struct nlattr **tca, unsigned long *arg) |
1da177e4 | 335 | { |
add93b61 PM |
336 | struct nlattr *opt = tca[TCA_OPTIONS]; |
337 | struct nlattr *tb[TCA_TCINDEX_MAX + 1]; | |
a8701a6c | 338 | struct tcindex_data *p = tp->root; |
1da177e4 | 339 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg; |
cee63723 | 340 | int err; |
1da177e4 | 341 | |
aa767bfe | 342 | pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p," |
1da177e4 LT |
343 | "p %p,r %p,*arg 0x%lx\n", |
344 | tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L); | |
345 | ||
346 | if (!opt) | |
347 | return 0; | |
348 | ||
6fa8c014 | 349 | err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy); |
cee63723 PM |
350 | if (err < 0) |
351 | return err; | |
1da177e4 | 352 | |
c1b52739 BL |
353 | return tcindex_set_parms(net, tp, base, handle, p, r, tb, |
354 | tca[TCA_RATE]); | |
1da177e4 LT |
355 | } |
356 | ||
357 | ||
358 | static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker) | |
359 | { | |
a8701a6c | 360 | struct tcindex_data *p = tp->root; |
aa767bfe | 361 | struct tcindex_filter *f, *next; |
1da177e4 LT |
362 | int i; |
363 | ||
aa767bfe | 364 | pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p); |
1da177e4 LT |
365 | if (p->perfect) { |
366 | for (i = 0; i < p->hash; i++) { | |
367 | if (!p->perfect[i].res.class) | |
368 | continue; | |
369 | if (walker->count >= walker->skip) { | |
370 | if (walker->fn(tp, | |
371 | (unsigned long) (p->perfect+i), walker) | |
372 | < 0) { | |
373 | walker->stop = 1; | |
374 | return; | |
375 | } | |
376 | } | |
377 | walker->count++; | |
378 | } | |
379 | } | |
380 | if (!p->h) | |
381 | return; | |
382 | for (i = 0; i < p->hash; i++) { | |
383 | for (f = p->h[i]; f; f = next) { | |
384 | next = f->next; | |
385 | if (walker->count >= walker->skip) { | |
aa767bfe | 386 | if (walker->fn(tp, (unsigned long) &f->result, |
1da177e4 LT |
387 | walker) < 0) { |
388 | walker->stop = 1; | |
389 | return; | |
390 | } | |
391 | } | |
392 | walker->count++; | |
393 | } | |
394 | } | |
395 | } | |
396 | ||
397 | ||
398 | static int tcindex_destroy_element(struct tcf_proto *tp, | |
399 | unsigned long arg, struct tcf_walker *walker) | |
400 | { | |
401 | return __tcindex_delete(tp, arg, 0); | |
402 | } | |
403 | ||
404 | ||
405 | static void tcindex_destroy(struct tcf_proto *tp) | |
406 | { | |
a8701a6c | 407 | struct tcindex_data *p = tp->root; |
1da177e4 LT |
408 | struct tcf_walker walker; |
409 | ||
aa767bfe | 410 | pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p); |
1da177e4 LT |
411 | walker.count = 0; |
412 | walker.skip = 0; | |
413 | walker.fn = &tcindex_destroy_element; | |
aa767bfe | 414 | tcindex_walk(tp, &walker); |
a51482bd JJ |
415 | kfree(p->perfect); |
416 | kfree(p->h); | |
1da177e4 LT |
417 | kfree(p); |
418 | tp->root = NULL; | |
419 | } | |
420 | ||
421 | ||
832d1d5b | 422 | static int tcindex_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, |
1da177e4 LT |
423 | struct sk_buff *skb, struct tcmsg *t) |
424 | { | |
a8701a6c | 425 | struct tcindex_data *p = tp->root; |
1da177e4 | 426 | struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh; |
27a884dc | 427 | unsigned char *b = skb_tail_pointer(skb); |
4b3550ef | 428 | struct nlattr *nest; |
1da177e4 | 429 | |
aa767bfe SH |
430 | pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n", |
431 | tp, fh, skb, t, p, r, b); | |
432 | pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h); | |
4b3550ef PM |
433 | |
434 | nest = nla_nest_start(skb, TCA_OPTIONS); | |
435 | if (nest == NULL) | |
436 | goto nla_put_failure; | |
437 | ||
1da177e4 LT |
438 | if (!fh) { |
439 | t->tcm_handle = ~0; /* whatever ... */ | |
1b34ec43 DM |
440 | if (nla_put_u32(skb, TCA_TCINDEX_HASH, p->hash) || |
441 | nla_put_u16(skb, TCA_TCINDEX_MASK, p->mask) || | |
442 | nla_put_u32(skb, TCA_TCINDEX_SHIFT, p->shift) || | |
443 | nla_put_u32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through)) | |
444 | goto nla_put_failure; | |
4b3550ef | 445 | nla_nest_end(skb, nest); |
1da177e4 LT |
446 | } else { |
447 | if (p->perfect) { | |
448 | t->tcm_handle = r-p->perfect; | |
449 | } else { | |
450 | struct tcindex_filter *f; | |
451 | int i; | |
452 | ||
453 | t->tcm_handle = 0; | |
454 | for (i = 0; !t->tcm_handle && i < p->hash; i++) { | |
455 | for (f = p->h[i]; !t->tcm_handle && f; | |
456 | f = f->next) { | |
457 | if (&f->result == r) | |
458 | t->tcm_handle = f->key; | |
459 | } | |
460 | } | |
461 | } | |
aa767bfe | 462 | pr_debug("handle = %d\n", t->tcm_handle); |
1b34ec43 DM |
463 | if (r->res.class && |
464 | nla_put_u32(skb, TCA_TCINDEX_CLASSID, r->res.classid)) | |
465 | goto nla_put_failure; | |
1da177e4 | 466 | |
5da57f42 | 467 | if (tcf_exts_dump(skb, &r->exts) < 0) |
add93b61 | 468 | goto nla_put_failure; |
4b3550ef | 469 | nla_nest_end(skb, nest); |
1da177e4 | 470 | |
5da57f42 | 471 | if (tcf_exts_dump_stats(skb, &r->exts) < 0) |
add93b61 | 472 | goto nla_put_failure; |
1da177e4 | 473 | } |
10297b99 | 474 | |
1da177e4 LT |
475 | return skb->len; |
476 | ||
add93b61 | 477 | nla_put_failure: |
dc5fc579 | 478 | nlmsg_trim(skb, b); |
1da177e4 LT |
479 | return -1; |
480 | } | |
481 | ||
2eb9d75c | 482 | static struct tcf_proto_ops cls_tcindex_ops __read_mostly = { |
1da177e4 LT |
483 | .kind = "tcindex", |
484 | .classify = tcindex_classify, | |
485 | .init = tcindex_init, | |
486 | .destroy = tcindex_destroy, | |
487 | .get = tcindex_get, | |
488 | .put = tcindex_put, | |
489 | .change = tcindex_change, | |
490 | .delete = tcindex_delete, | |
491 | .walk = tcindex_walk, | |
492 | .dump = tcindex_dump, | |
493 | .owner = THIS_MODULE, | |
494 | }; | |
495 | ||
496 | static int __init init_tcindex(void) | |
497 | { | |
498 | return register_tcf_proto_ops(&cls_tcindex_ops); | |
499 | } | |
500 | ||
10297b99 | 501 | static void __exit exit_tcindex(void) |
1da177e4 LT |
502 | { |
503 | unregister_tcf_proto_ops(&cls_tcindex_ops); | |
504 | } | |
505 | ||
506 | module_init(init_tcindex) | |
507 | module_exit(exit_tcindex) | |
508 | MODULE_LICENSE("GPL"); |