[NET_SCHED]: Use nla_nest_start/nla_nest_end
[linux-2.6.git] / 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 nlattr **tb,
134                                   struct nlattr *est)
135 {
136         int err = -EINVAL;
137         struct tcf_exts e;
138         struct tcf_ematch_tree t;
139
140         if (tb[TCA_BASIC_CLASSID])
141                 if (nla_len(tb[TCA_BASIC_CLASSID]) < 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], &t);
149         if (err < 0)
150                 goto errout;
151
152         if (tb[TCA_BASIC_CLASSID]) {
153                 f->res.classid = *(u32*)nla_data(tb[TCA_BASIC_CLASSID]);
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 nlattr **tca, unsigned long *arg)
168 {
169         int err;
170         struct basic_head *head = (struct basic_head *) tp->root;
171         struct nlattr *tb[TCA_BASIC_MAX + 1];
172         struct basic_filter *f = (struct basic_filter *) *arg;
173
174         if (tca[TCA_OPTIONS] == NULL)
175                 return -EINVAL;
176
177         err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS], NULL);
178         if (err < 0)
179                 return err;
180
181         if (f != NULL) {
182                 if (handle && f->handle != handle)
183                         return -EINVAL;
184                 return basic_set_parms(tp, f, base, tb, tca[TCA_RATE]);
185         }
186
187         err = -ENOBUFS;
188         f = kzalloc(sizeof(*f), GFP_KERNEL);
189         if (f == NULL)
190                 goto errout;
191
192         err = -EINVAL;
193         if (handle)
194                 f->handle = handle;
195         else {
196                 unsigned int i = 0x80000000;
197                 do {
198                         if (++head->hgenerator == 0x7FFFFFFF)
199                                 head->hgenerator = 1;
200                 } while (--i > 0 && basic_get(tp, head->hgenerator));
201
202                 if (i <= 0) {
203                         printk(KERN_ERR "Insufficient number of handles\n");
204                         goto errout;
205                 }
206
207                 f->handle = head->hgenerator;
208         }
209
210         err = basic_set_parms(tp, f, base, tb, tca[TCA_RATE]);
211         if (err < 0)
212                 goto errout;
213
214         tcf_tree_lock(tp);
215         list_add(&f->link, &head->flist);
216         tcf_tree_unlock(tp);
217         *arg = (unsigned long) f;
218
219         return 0;
220 errout:
221         if (*arg == 0UL && f)
222                 kfree(f);
223
224         return err;
225 }
226
227 static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
228 {
229         struct basic_head *head = (struct basic_head *) tp->root;
230         struct basic_filter *f;
231
232         list_for_each_entry(f, &head->flist, link) {
233                 if (arg->count < arg->skip)
234                         goto skip;
235
236                 if (arg->fn(tp, (unsigned long) f, arg) < 0) {
237                         arg->stop = 1;
238                         break;
239                 }
240 skip:
241                 arg->count++;
242         }
243 }
244
245 static int basic_dump(struct tcf_proto *tp, unsigned long fh,
246                       struct sk_buff *skb, struct tcmsg *t)
247 {
248         struct basic_filter *f = (struct basic_filter *) fh;
249         struct nlattr *nest;
250
251         if (f == NULL)
252                 return skb->len;
253
254         t->tcm_handle = f->handle;
255
256         nest = nla_nest_start(skb, TCA_OPTIONS);
257         if (nest == NULL)
258                 goto nla_put_failure;
259
260         if (f->res.classid)
261                 NLA_PUT(skb, TCA_BASIC_CLASSID, sizeof(u32), &f->res.classid);
262
263         if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
264             tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
265                 goto nla_put_failure;
266
267         nla_nest_end(skb, nest);
268         return skb->len;
269
270 nla_put_failure:
271         nla_nest_cancel(skb, nest);
272         return -1;
273 }
274
275 static struct tcf_proto_ops cls_basic_ops __read_mostly = {
276         .kind           =       "basic",
277         .classify       =       basic_classify,
278         .init           =       basic_init,
279         .destroy        =       basic_destroy,
280         .get            =       basic_get,
281         .put            =       basic_put,
282         .change         =       basic_change,
283         .delete         =       basic_delete,
284         .walk           =       basic_walk,
285         .dump           =       basic_dump,
286         .owner          =       THIS_MODULE,
287 };
288
289 static int __init init_basic(void)
290 {
291         return register_tcf_proto_ops(&cls_basic_ops);
292 }
293
294 static void __exit exit_basic(void)
295 {
296         unregister_tcf_proto_ops(&cls_basic_ops);
297 }
298
299 module_init(init_basic)
300 module_exit(exit_basic)
301 MODULE_LICENSE("GPL");
302