Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-2.6] / net / sched / cls_basic.c
1 /*
2  * net/sched/cls_basic.c        Basic Packet Classifier.
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:     Thomas Graf <tgraf@suug.ch>
10  */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/errno.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/skbuff.h>
19 #include <net/netlink.h>
20 #include <net/act_api.h>
21 #include <net/pkt_cls.h>
22
23 struct basic_head
24 {
25         u32                     hgenerator;
26         struct list_head        flist;
27 };
28
29 struct basic_filter
30 {
31         u32                     handle;
32         struct tcf_exts         exts;
33         struct tcf_ematch_tree  ematches;
34         struct tcf_result       res;
35         struct list_head        link;
36 };
37
38 static struct tcf_ext_map basic_ext_map = {
39         .action = TCA_BASIC_ACT,
40         .police = TCA_BASIC_POLICE
41 };
42
43 static int basic_classify(struct sk_buff *skb, struct tcf_proto *tp,
44                           struct tcf_result *res)
45 {
46         int r;
47         struct basic_head *head = (struct basic_head *) tp->root;
48         struct basic_filter *f;
49
50         list_for_each_entry(f, &head->flist, link) {
51                 if (!tcf_em_tree_match(skb, &f->ematches, NULL))
52                         continue;
53                 *res = f->res;
54                 r = tcf_exts_exec(skb, &f->exts, res);
55                 if (r < 0)
56                         continue;
57                 return r;
58         }
59         return -1;
60 }
61
62 static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
63 {
64         unsigned long l = 0UL;
65         struct basic_head *head = (struct basic_head *) tp->root;
66         struct basic_filter *f;
67
68         if (head == NULL)
69                 return 0UL;
70
71         list_for_each_entry(f, &head->flist, link)
72                 if (f->handle == handle)
73                         l = (unsigned long) f;
74
75         return l;
76 }
77
78 static void basic_put(struct tcf_proto *tp, unsigned long f)
79 {
80 }
81
82 static int basic_init(struct tcf_proto *tp)
83 {
84         struct basic_head *head;
85
86         head = kzalloc(sizeof(*head), GFP_KERNEL);
87         if (head == NULL)
88                 return -ENOBUFS;
89         INIT_LIST_HEAD(&head->flist);
90         tp->root = head;
91         return 0;
92 }
93
94 static inline void basic_delete_filter(struct tcf_proto *tp,
95                                        struct basic_filter *f)
96 {
97         tcf_unbind_filter(tp, &f->res);
98         tcf_exts_destroy(tp, &f->exts);
99         tcf_em_tree_destroy(tp, &f->ematches);
100         kfree(f);
101 }
102
103 static void basic_destroy(struct tcf_proto *tp)
104 {
105         struct basic_head *head = (struct basic_head *) xchg(&tp->root, NULL);
106         struct basic_filter *f, *n;
107
108         list_for_each_entry_safe(f, n, &head->flist, link) {
109                 list_del(&f->link);
110                 basic_delete_filter(tp, f);
111         }
112         kfree(head);
113 }
114
115 static int basic_delete(struct tcf_proto *tp, unsigned long arg)
116 {
117         struct basic_head *head = (struct basic_head *) tp->root;
118         struct basic_filter *t, *f = (struct basic_filter *) arg;
119
120         list_for_each_entry(t, &head->flist, link)
121                 if (t == f) {
122                         tcf_tree_lock(tp);
123                         list_del(&t->link);
124                         tcf_tree_unlock(tp);
125                         basic_delete_filter(tp, t);
126                         return 0;
127                 }
128
129         return -ENOENT;
130 }
131
132 static inline int basic_set_parms(struct tcf_proto *tp, struct basic_filter *f,
133                                   unsigned long base, struct rtattr **tb,
134                                   struct rtattr *est)
135 {
136         int err = -EINVAL;
137         struct tcf_exts e;
138         struct tcf_ematch_tree t;
139
140         if (tb[TCA_BASIC_CLASSID-1])
141                 if (RTA_PAYLOAD(tb[TCA_BASIC_CLASSID-1]) < sizeof(u32))
142                         return err;
143
144         err = tcf_exts_validate(tp, tb, est, &e, &basic_ext_map);
145         if (err < 0)
146                 return err;
147
148         err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES-1], &t);
149         if (err < 0)
150                 goto errout;
151
152         if (tb[TCA_BASIC_CLASSID-1]) {
153                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_BASIC_CLASSID-1]);
154                 tcf_bind_filter(tp, &f->res, base);
155         }
156
157         tcf_exts_change(tp, &f->exts, &e);
158         tcf_em_tree_change(tp, &f->ematches, &t);
159
160         return 0;
161 errout:
162         tcf_exts_destroy(tp, &e);
163         return err;
164 }
165
166 static int basic_change(struct tcf_proto *tp, unsigned long base, u32 handle,
167                         struct rtattr **tca, unsigned long *arg)
168 {
169         int err = -EINVAL;
170         struct basic_head *head = (struct basic_head *) tp->root;
171         struct rtattr *tb[TCA_BASIC_MAX];
172         struct basic_filter *f = (struct basic_filter *) *arg;
173
174         if (tca[TCA_OPTIONS-1] == NULL)
175                 return -EINVAL;
176
177         if (rtattr_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS-1]) < 0)
178                 return -EINVAL;
179
180         if (f != NULL) {
181                 if (handle && f->handle != handle)
182                         return -EINVAL;
183                 return basic_set_parms(tp, f, base, tb, tca[TCA_RATE-1]);
184         }
185
186         err = -ENOBUFS;
187         f = kzalloc(sizeof(*f), GFP_KERNEL);
188         if (f == NULL)
189                 goto errout;
190
191         err = -EINVAL;
192         if (handle)
193                 f->handle = handle;
194         else {
195                 unsigned int i = 0x80000000;
196                 do {
197                         if (++head->hgenerator == 0x7FFFFFFF)
198                                 head->hgenerator = 1;
199                 } while (--i > 0 && basic_get(tp, head->hgenerator));
200
201                 if (i <= 0) {
202                         printk(KERN_ERR "Insufficient number of handles\n");
203                         goto errout;
204                 }
205
206                 f->handle = head->hgenerator;
207         }
208
209         err = basic_set_parms(tp, f, base, tb, tca[TCA_RATE-1]);
210         if (err < 0)
211                 goto errout;
212
213         tcf_tree_lock(tp);
214         list_add(&f->link, &head->flist);
215         tcf_tree_unlock(tp);
216         *arg = (unsigned long) f;
217
218         return 0;
219 errout:
220         if (*arg == 0UL && f)
221                 kfree(f);
222
223         return err;
224 }
225
226 static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
227 {
228         struct basic_head *head = (struct basic_head *) tp->root;
229         struct basic_filter *f;
230
231         list_for_each_entry(f, &head->flist, link) {
232                 if (arg->count < arg->skip)
233                         goto skip;
234
235                 if (arg->fn(tp, (unsigned long) f, arg) < 0) {
236                         arg->stop = 1;
237                         break;
238                 }
239 skip:
240                 arg->count++;
241         }
242 }
243
244 static int basic_dump(struct tcf_proto *tp, unsigned long fh,
245                       struct sk_buff *skb, struct tcmsg *t)
246 {
247         struct basic_filter *f = (struct basic_filter *) fh;
248         unsigned char *b = skb_tail_pointer(skb);
249         struct rtattr *rta;
250
251         if (f == NULL)
252                 return skb->len;
253
254         t->tcm_handle = f->handle;
255
256         rta = (struct rtattr *) b;
257         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
258
259         if (f->res.classid)
260                 RTA_PUT(skb, TCA_BASIC_CLASSID, sizeof(u32), &f->res.classid);
261
262         if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
263             tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
264                 goto rtattr_failure;
265
266         rta->rta_len = skb_tail_pointer(skb) - b;
267         return skb->len;
268
269 rtattr_failure:
270         nlmsg_trim(skb, b);
271         return -1;
272 }
273
274 static struct tcf_proto_ops cls_basic_ops = {
275         .kind           =       "basic",
276         .classify       =       basic_classify,
277         .init           =       basic_init,
278         .destroy        =       basic_destroy,
279         .get            =       basic_get,
280         .put            =       basic_put,
281         .change         =       basic_change,
282         .delete         =       basic_delete,
283         .walk           =       basic_walk,
284         .dump           =       basic_dump,
285         .owner          =       THIS_MODULE,
286 };
287
288 static int __init init_basic(void)
289 {
290         return register_tcf_proto_ops(&cls_basic_ops);
291 }
292
293 static void __exit exit_basic(void)
294 {
295         unregister_tcf_proto_ops(&cls_basic_ops);
296 }
297
298 module_init(init_basic)
299 module_exit(exit_basic)
300 MODULE_LICENSE("GPL");
301