Merge branches 'release' and 'menlo' into release
[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 const 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 const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
133         [TCA_BASIC_CLASSID]     = { .type = NLA_U32 },
134         [TCA_BASIC_EMATCHES]    = { .type = NLA_NESTED },
135 };
136
137 static inline int basic_set_parms(struct tcf_proto *tp, struct basic_filter *f,
138                                   unsigned long base, struct nlattr **tb,
139                                   struct nlattr *est)
140 {
141         int err = -EINVAL;
142         struct tcf_exts e;
143         struct tcf_ematch_tree t;
144
145         err = tcf_exts_validate(tp, tb, est, &e, &basic_ext_map);
146         if (err < 0)
147                 return err;
148
149         err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
150         if (err < 0)
151                 goto errout;
152
153         if (tb[TCA_BASIC_CLASSID]) {
154                 f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
155                 tcf_bind_filter(tp, &f->res, base);
156         }
157
158         tcf_exts_change(tp, &f->exts, &e);
159         tcf_em_tree_change(tp, &f->ematches, &t);
160
161         return 0;
162 errout:
163         tcf_exts_destroy(tp, &e);
164         return err;
165 }
166
167 static int basic_change(struct tcf_proto *tp, unsigned long base, u32 handle,
168                         struct nlattr **tca, unsigned long *arg)
169 {
170         int err;
171         struct basic_head *head = (struct basic_head *) tp->root;
172         struct nlattr *tb[TCA_BASIC_MAX + 1];
173         struct basic_filter *f = (struct basic_filter *) *arg;
174
175         if (tca[TCA_OPTIONS] == NULL)
176                 return -EINVAL;
177
178         err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
179                                basic_policy);
180         if (err < 0)
181                 return err;
182
183         if (f != NULL) {
184                 if (handle && f->handle != handle)
185                         return -EINVAL;
186                 return basic_set_parms(tp, f, base, tb, tca[TCA_RATE]);
187         }
188
189         err = -ENOBUFS;
190         f = kzalloc(sizeof(*f), GFP_KERNEL);
191         if (f == NULL)
192                 goto errout;
193
194         err = -EINVAL;
195         if (handle)
196                 f->handle = handle;
197         else {
198                 unsigned int i = 0x80000000;
199                 do {
200                         if (++head->hgenerator == 0x7FFFFFFF)
201                                 head->hgenerator = 1;
202                 } while (--i > 0 && basic_get(tp, head->hgenerator));
203
204                 if (i <= 0) {
205                         printk(KERN_ERR "Insufficient number of handles\n");
206                         goto errout;
207                 }
208
209                 f->handle = head->hgenerator;
210         }
211
212         err = basic_set_parms(tp, f, base, tb, tca[TCA_RATE]);
213         if (err < 0)
214                 goto errout;
215
216         tcf_tree_lock(tp);
217         list_add(&f->link, &head->flist);
218         tcf_tree_unlock(tp);
219         *arg = (unsigned long) f;
220
221         return 0;
222 errout:
223         if (*arg == 0UL && f)
224                 kfree(f);
225
226         return err;
227 }
228
229 static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
230 {
231         struct basic_head *head = (struct basic_head *) tp->root;
232         struct basic_filter *f;
233
234         list_for_each_entry(f, &head->flist, link) {
235                 if (arg->count < arg->skip)
236                         goto skip;
237
238                 if (arg->fn(tp, (unsigned long) f, arg) < 0) {
239                         arg->stop = 1;
240                         break;
241                 }
242 skip:
243                 arg->count++;
244         }
245 }
246
247 static int basic_dump(struct tcf_proto *tp, unsigned long fh,
248                       struct sk_buff *skb, struct tcmsg *t)
249 {
250         struct basic_filter *f = (struct basic_filter *) fh;
251         struct nlattr *nest;
252
253         if (f == NULL)
254                 return skb->len;
255
256         t->tcm_handle = f->handle;
257
258         nest = nla_nest_start(skb, TCA_OPTIONS);
259         if (nest == NULL)
260                 goto nla_put_failure;
261
262         if (f->res.classid)
263                 NLA_PUT_U32(skb, TCA_BASIC_CLASSID, f->res.classid);
264
265         if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
266             tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
267                 goto nla_put_failure;
268
269         nla_nest_end(skb, nest);
270         return skb->len;
271
272 nla_put_failure:
273         nla_nest_cancel(skb, nest);
274         return -1;
275 }
276
277 static struct tcf_proto_ops cls_basic_ops __read_mostly = {
278         .kind           =       "basic",
279         .classify       =       basic_classify,
280         .init           =       basic_init,
281         .destroy        =       basic_destroy,
282         .get            =       basic_get,
283         .put            =       basic_put,
284         .change         =       basic_change,
285         .delete         =       basic_delete,
286         .walk           =       basic_walk,
287         .dump           =       basic_dump,
288         .owner          =       THIS_MODULE,
289 };
290
291 static int __init init_basic(void)
292 {
293         return register_tcf_proto_ops(&cls_basic_ops);
294 }
295
296 static void __exit exit_basic(void)
297 {
298         unregister_tcf_proto_ops(&cls_basic_ops);
299 }
300
301 module_init(init_basic)
302 module_exit(exit_basic)
303 MODULE_LICENSE("GPL");
304