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