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