e3dfbb3046c0cf52e44dcd58fded8da95595eba2
[linux-2.6.git] / net / sched / cls_fw.c
1 /*
2  * net/sched/cls_fw.c   Classifier mapping ipchains' fwmark to traffic class.
3  *
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.
8  *
9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10  *
11  * Changes:
12  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_walk off by one
13  * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_delete killed all the filter (and kernel).
14  * Alex <alex@pilotsoft.com> : 2004xxyy: Added Action extension
15  *
16  * JHS: We should remove the CONFIG_NET_CLS_IND from here
17  * eventually when the meta match extension is made available
18  *
19  */
20
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/kernel.h>
24 #include <linux/string.h>
25 #include <linux/errno.h>
26 #include <linux/skbuff.h>
27 #include <net/netlink.h>
28 #include <net/act_api.h>
29 #include <net/pkt_cls.h>
30
31 #define HTSIZE (PAGE_SIZE/sizeof(struct fw_filter *))
32
33 struct fw_head
34 {
35         struct fw_filter *ht[HTSIZE];
36         u32 mask;
37 };
38
39 struct fw_filter
40 {
41         struct fw_filter        *next;
42         u32                     id;
43         struct tcf_result       res;
44 #ifdef CONFIG_NET_CLS_IND
45         char                    indev[IFNAMSIZ];
46 #endif /* CONFIG_NET_CLS_IND */
47         struct tcf_exts         exts;
48 };
49
50 static struct tcf_ext_map fw_ext_map = {
51         .action = TCA_FW_ACT,
52         .police = TCA_FW_POLICE
53 };
54
55 static __inline__ int fw_hash(u32 handle)
56 {
57         if (HTSIZE == 4096)
58                 return ((handle >> 24) & 0xFFF) ^
59                        ((handle >> 12) & 0xFFF) ^
60                        (handle & 0xFFF);
61         else if (HTSIZE == 2048)
62                 return ((handle >> 22) & 0x7FF) ^
63                        ((handle >> 11) & 0x7FF) ^
64                        (handle & 0x7FF);
65         else if (HTSIZE == 1024)
66                 return ((handle >> 20) & 0x3FF) ^
67                        ((handle >> 10) & 0x3FF) ^
68                        (handle & 0x3FF);
69         else if (HTSIZE == 512)
70                 return (handle >> 27) ^
71                        ((handle >> 18) & 0x1FF) ^
72                        ((handle >> 9) & 0x1FF) ^
73                        (handle & 0x1FF);
74         else if (HTSIZE == 256) {
75                 u8 *t = (u8 *) &handle;
76                 return t[0] ^ t[1] ^ t[2] ^ t[3];
77         } else
78                 return handle & (HTSIZE - 1);
79 }
80
81 static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
82                           struct tcf_result *res)
83 {
84         struct fw_head *head = (struct fw_head*)tp->root;
85         struct fw_filter *f;
86         int r;
87         u32 id = skb->mark;
88
89         if (head != NULL) {
90                 id &= head->mask;
91                 for (f=head->ht[fw_hash(id)]; f; f=f->next) {
92                         if (f->id == id) {
93                                 *res = f->res;
94 #ifdef CONFIG_NET_CLS_IND
95                                 if (!tcf_match_indev(skb, f->indev))
96                                         continue;
97 #endif /* CONFIG_NET_CLS_IND */
98                                 r = tcf_exts_exec(skb, &f->exts, res);
99                                 if (r < 0)
100                                         continue;
101
102                                 return r;
103                         }
104                 }
105         } else {
106                 /* old method */
107                 if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
108                         res->classid = id;
109                         res->class = 0;
110                         return 0;
111                 }
112         }
113
114         return -1;
115 }
116
117 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
118 {
119         struct fw_head *head = (struct fw_head*)tp->root;
120         struct fw_filter *f;
121
122         if (head == NULL)
123                 return 0;
124
125         for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
126                 if (f->id == handle)
127                         return (unsigned long)f;
128         }
129         return 0;
130 }
131
132 static void fw_put(struct tcf_proto *tp, unsigned long f)
133 {
134 }
135
136 static int fw_init(struct tcf_proto *tp)
137 {
138         return 0;
139 }
140
141 static inline void
142 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
143 {
144         tcf_unbind_filter(tp, &f->res);
145         tcf_exts_destroy(tp, &f->exts);
146         kfree(f);
147 }
148
149 static void fw_destroy(struct tcf_proto *tp)
150 {
151         struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
152         struct fw_filter *f;
153         int h;
154
155         if (head == NULL)
156                 return;
157
158         for (h=0; h<HTSIZE; h++) {
159                 while ((f=head->ht[h]) != NULL) {
160                         head->ht[h] = f->next;
161                         fw_delete_filter(tp, f);
162                 }
163         }
164         kfree(head);
165 }
166
167 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
168 {
169         struct fw_head *head = (struct fw_head*)tp->root;
170         struct fw_filter *f = (struct fw_filter*)arg;
171         struct fw_filter **fp;
172
173         if (head == NULL || f == NULL)
174                 goto out;
175
176         for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
177                 if (*fp == f) {
178                         tcf_tree_lock(tp);
179                         *fp = f->next;
180                         tcf_tree_unlock(tp);
181                         fw_delete_filter(tp, f);
182                         return 0;
183                 }
184         }
185 out:
186         return -EINVAL;
187 }
188
189 static int
190 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
191         struct nlattr **tb, struct nlattr **tca, unsigned long base)
192 {
193         struct fw_head *head = (struct fw_head *)tp->root;
194         struct tcf_exts e;
195         u32 mask;
196         int err;
197
198         err = tcf_exts_validate(tp, tb, tca[TCA_RATE], &e, &fw_ext_map);
199         if (err < 0)
200                 return err;
201
202         err = -EINVAL;
203         if (tb[TCA_FW_CLASSID]) {
204                 if (nla_len(tb[TCA_FW_CLASSID]) != sizeof(u32))
205                         goto errout;
206                 f->res.classid = *(u32*)nla_data(tb[TCA_FW_CLASSID]);
207                 tcf_bind_filter(tp, &f->res, base);
208         }
209
210 #ifdef CONFIG_NET_CLS_IND
211         if (tb[TCA_FW_INDEV]) {
212                 err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV]);
213                 if (err < 0)
214                         goto errout;
215         }
216 #endif /* CONFIG_NET_CLS_IND */
217
218         if (tb[TCA_FW_MASK]) {
219                 if (nla_len(tb[TCA_FW_MASK]) != sizeof(u32))
220                         goto errout;
221                 mask = *(u32*)nla_data(tb[TCA_FW_MASK]);
222                 if (mask != head->mask)
223                         goto errout;
224         } else if (head->mask != 0xFFFFFFFF)
225                 goto errout;
226
227         tcf_exts_change(tp, &f->exts, &e);
228
229         return 0;
230 errout:
231         tcf_exts_destroy(tp, &e);
232         return err;
233 }
234
235 static int fw_change(struct tcf_proto *tp, unsigned long base,
236                      u32 handle,
237                      struct nlattr **tca,
238                      unsigned long *arg)
239 {
240         struct fw_head *head = (struct fw_head*)tp->root;
241         struct fw_filter *f = (struct fw_filter *) *arg;
242         struct nlattr *opt = tca[TCA_OPTIONS];
243         struct nlattr *tb[TCA_FW_MAX + 1];
244         int err;
245
246         if (!opt)
247                 return handle ? -EINVAL : 0;
248
249         err = nla_parse_nested(tb, TCA_FW_MAX, opt, NULL);
250         if (err < 0)
251                 return err;
252
253         if (f != NULL) {
254                 if (f->id != handle && handle)
255                         return -EINVAL;
256                 return fw_change_attrs(tp, f, tb, tca, base);
257         }
258
259         if (!handle)
260                 return -EINVAL;
261
262         if (head == NULL) {
263                 u32 mask = 0xFFFFFFFF;
264                 if (tb[TCA_FW_MASK]) {
265                         if (nla_len(tb[TCA_FW_MASK]) != sizeof(u32))
266                                 return -EINVAL;
267                         mask = *(u32*)nla_data(tb[TCA_FW_MASK]);
268                 }
269
270                 head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
271                 if (head == NULL)
272                         return -ENOBUFS;
273                 head->mask = mask;
274
275                 tcf_tree_lock(tp);
276                 tp->root = head;
277                 tcf_tree_unlock(tp);
278         }
279
280         f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
281         if (f == NULL)
282                 return -ENOBUFS;
283
284         f->id = handle;
285
286         err = fw_change_attrs(tp, f, tb, tca, base);
287         if (err < 0)
288                 goto errout;
289
290         f->next = head->ht[fw_hash(handle)];
291         tcf_tree_lock(tp);
292         head->ht[fw_hash(handle)] = f;
293         tcf_tree_unlock(tp);
294
295         *arg = (unsigned long)f;
296         return 0;
297
298 errout:
299         kfree(f);
300         return err;
301 }
302
303 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
304 {
305         struct fw_head *head = (struct fw_head*)tp->root;
306         int h;
307
308         if (head == NULL)
309                 arg->stop = 1;
310
311         if (arg->stop)
312                 return;
313
314         for (h = 0; h < HTSIZE; h++) {
315                 struct fw_filter *f;
316
317                 for (f = head->ht[h]; f; f = f->next) {
318                         if (arg->count < arg->skip) {
319                                 arg->count++;
320                                 continue;
321                         }
322                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
323                                 arg->stop = 1;
324                                 return;
325                         }
326                         arg->count++;
327                 }
328         }
329 }
330
331 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
332                    struct sk_buff *skb, struct tcmsg *t)
333 {
334         struct fw_head *head = (struct fw_head *)tp->root;
335         struct fw_filter *f = (struct fw_filter*)fh;
336         unsigned char *b = skb_tail_pointer(skb);
337         struct nlattr *nest;
338
339         if (f == NULL)
340                 return skb->len;
341
342         t->tcm_handle = f->id;
343
344         if (!f->res.classid && !tcf_exts_is_available(&f->exts))
345                 return skb->len;
346
347         nest = nla_nest_start(skb, TCA_OPTIONS);
348         if (nest == NULL)
349                 goto nla_put_failure;
350
351         if (f->res.classid)
352                 NLA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
353 #ifdef CONFIG_NET_CLS_IND
354         if (strlen(f->indev))
355                 NLA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
356 #endif /* CONFIG_NET_CLS_IND */
357         if (head->mask != 0xFFFFFFFF)
358                 NLA_PUT(skb, TCA_FW_MASK, 4, &head->mask);
359
360         if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
361                 goto nla_put_failure;
362
363         nla_nest_end(skb, nest);
364
365         if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
366                 goto nla_put_failure;
367
368         return skb->len;
369
370 nla_put_failure:
371         nlmsg_trim(skb, b);
372         return -1;
373 }
374
375 static struct tcf_proto_ops cls_fw_ops __read_mostly = {
376         .kind           =       "fw",
377         .classify       =       fw_classify,
378         .init           =       fw_init,
379         .destroy        =       fw_destroy,
380         .get            =       fw_get,
381         .put            =       fw_put,
382         .change         =       fw_change,
383         .delete         =       fw_delete,
384         .walk           =       fw_walk,
385         .dump           =       fw_dump,
386         .owner          =       THIS_MODULE,
387 };
388
389 static int __init init_fw(void)
390 {
391         return register_tcf_proto_ops(&cls_fw_ops);
392 }
393
394 static void __exit exit_fw(void)
395 {
396         unregister_tcf_proto_ops(&cls_fw_ops);
397 }
398
399 module_init(init_fw)
400 module_exit(exit_fw)
401 MODULE_LICENSE("GPL");