Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik...
[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/config.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/sched.h>
17 #include <linux/string.h>
18 #include <linux/mm.h>
19 #include <linux/errno.h>
20 #include <linux/rtnetlink.h>
21 #include <linux/skbuff.h>
22 #include <net/act_api.h>
23 #include <net/pkt_cls.h>
24
25 struct basic_head
26 {
27         u32                     hgenerator;
28         struct list_head        flist;
29 };
30
31 struct basic_filter
32 {
33         u32                     handle;
34         struct tcf_exts         exts;
35         struct tcf_ematch_tree  ematches;
36         struct tcf_result       res;
37         struct list_head        link;
38 };
39
40 static struct tcf_ext_map basic_ext_map = {
41         .action = TCA_BASIC_ACT,
42         .police = TCA_BASIC_POLICE
43 };
44
45 static int basic_classify(struct sk_buff *skb, struct tcf_proto *tp,
46                           struct tcf_result *res)
47 {
48         int r;
49         struct basic_head *head = (struct basic_head *) tp->root;
50         struct basic_filter *f;
51
52         list_for_each_entry(f, &head->flist, link) {
53                 if (!tcf_em_tree_match(skb, &f->ematches, NULL))
54                         continue;
55                 *res = f->res;
56                 r = tcf_exts_exec(skb, &f->exts, res);
57                 if (r < 0)
58                         continue;
59                 return r;
60         }
61         return -1;
62 }
63
64 static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
65 {
66         unsigned long l = 0UL;
67         struct basic_head *head = (struct basic_head *) tp->root;
68         struct basic_filter *f;
69
70         if (head == NULL)
71                 return 0UL;
72
73         list_for_each_entry(f, &head->flist, link)
74                 if (f->handle == handle)
75                         l = (unsigned long) f;
76
77         return l;
78 }
79
80 static void basic_put(struct tcf_proto *tp, unsigned long f)
81 {
82 }
83
84 static int basic_init(struct tcf_proto *tp)
85 {
86         return 0;
87 }
88
89 static inline void basic_delete_filter(struct tcf_proto *tp,
90                                        struct basic_filter *f)
91 {
92         tcf_unbind_filter(tp, &f->res);
93         tcf_exts_destroy(tp, &f->exts);
94         tcf_em_tree_destroy(tp, &f->ematches);
95         kfree(f);
96 }
97
98 static void basic_destroy(struct tcf_proto *tp)
99 {
100         struct basic_head *head = (struct basic_head *) xchg(&tp->root, NULL);
101         struct basic_filter *f, *n;
102         
103         list_for_each_entry_safe(f, n, &head->flist, link) {
104                 list_del(&f->link);
105                 basic_delete_filter(tp, f);
106         }
107 }
108
109 static int basic_delete(struct tcf_proto *tp, unsigned long arg)
110 {
111         struct basic_head *head = (struct basic_head *) tp->root;
112         struct basic_filter *t, *f = (struct basic_filter *) arg;
113
114         list_for_each_entry(t, &head->flist, link)
115                 if (t == f) {
116                         tcf_tree_lock(tp);
117                         list_del(&t->link);
118                         tcf_tree_unlock(tp);
119                         basic_delete_filter(tp, t);
120                         return 0;
121                 }
122
123         return -ENOENT;
124 }
125
126 static inline int basic_set_parms(struct tcf_proto *tp, struct basic_filter *f,
127                                   unsigned long base, struct rtattr **tb,
128                                   struct rtattr *est)
129 {
130         int err = -EINVAL;
131         struct tcf_exts e;
132         struct tcf_ematch_tree t;
133
134         if (tb[TCA_BASIC_CLASSID-1])
135                 if (RTA_PAYLOAD(tb[TCA_BASIC_CLASSID-1]) < sizeof(u32))
136                         return err;
137
138         err = tcf_exts_validate(tp, tb, est, &e, &basic_ext_map);
139         if (err < 0)
140                 return err;
141
142         err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES-1], &t);
143         if (err < 0)
144                 goto errout;
145
146         if (tb[TCA_BASIC_CLASSID-1]) {
147                 f->res.classid = *(u32*)RTA_DATA(tb[TCA_BASIC_CLASSID-1]);
148                 tcf_bind_filter(tp, &f->res, base);
149         }
150
151         tcf_exts_change(tp, &f->exts, &e);
152         tcf_em_tree_change(tp, &f->ematches, &t);
153
154         return 0;
155 errout:
156         tcf_exts_destroy(tp, &e);
157         return err;
158 }
159
160 static int basic_change(struct tcf_proto *tp, unsigned long base, u32 handle,
161                         struct rtattr **tca, unsigned long *arg)
162 {
163         int err = -EINVAL;
164         struct basic_head *head = (struct basic_head *) tp->root;
165         struct rtattr *tb[TCA_BASIC_MAX];
166         struct basic_filter *f = (struct basic_filter *) *arg;
167
168         if (tca[TCA_OPTIONS-1] == NULL)
169                 return -EINVAL;
170
171         if (rtattr_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS-1]) < 0)
172                 return -EINVAL;
173
174         if (f != NULL) {
175                 if (handle && f->handle != handle)
176                         return -EINVAL;
177                 return basic_set_parms(tp, f, base, tb, tca[TCA_RATE-1]);
178         }
179
180         err = -ENOBUFS;
181         if (head == NULL) {
182                 head = kmalloc(sizeof(*head), GFP_KERNEL);
183                 if (head == NULL)
184                         goto errout;
185
186                 memset(head, 0, sizeof(*head));
187                 INIT_LIST_HEAD(&head->flist);
188                 tp->root = head;
189         }
190
191         f = kmalloc(sizeof(*f), GFP_KERNEL);
192         if (f == NULL)
193                 goto errout;
194         memset(f, 0, sizeof(*f));
195
196         err = -EINVAL;
197         if (handle)
198                 f->handle = handle;
199         else {
200                 int i = 0x80000000;
201                 do {
202                         if (++head->hgenerator == 0x7FFFFFFF)
203                                 head->hgenerator = 1;
204                 } while (--i > 0 && basic_get(tp, head->hgenerator));
205
206                 if (i <= 0) {
207                         printk(KERN_ERR "Insufficient number of handles\n");
208                         goto errout;
209                 }
210
211                 f->handle = head->hgenerator;
212         }
213
214         err = basic_set_parms(tp, f, base, tb, tca[TCA_RATE-1]);
215         if (err < 0)
216                 goto errout;
217
218         tcf_tree_lock(tp);
219         list_add(&f->link, &head->flist);
220         tcf_tree_unlock(tp);
221         *arg = (unsigned long) f;
222
223         return 0;
224 errout:
225         if (*arg == 0UL && f)
226                 kfree(f);
227
228         return err;
229 }
230
231 static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
232 {
233         struct basic_head *head = (struct basic_head *) tp->root;
234         struct basic_filter *f;
235
236         list_for_each_entry(f, &head->flist, link) {
237                 if (arg->count < arg->skip)
238                         goto skip;
239
240                 if (arg->fn(tp, (unsigned long) f, arg) < 0) {
241                         arg->stop = 1;
242                         break;
243                 }
244 skip:
245                 arg->count++;
246         }
247 }
248
249 static int basic_dump(struct tcf_proto *tp, unsigned long fh,
250                       struct sk_buff *skb, struct tcmsg *t)
251 {
252         struct basic_filter *f = (struct basic_filter *) fh;
253         unsigned char *b = skb->tail;
254         struct rtattr *rta;
255
256         if (f == NULL)
257                 return skb->len;
258
259         t->tcm_handle = f->handle;
260
261         rta = (struct rtattr *) b;
262         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
263
264         if (f->res.classid)
265                 RTA_PUT(skb, TCA_BASIC_CLASSID, sizeof(u32), &f->res.classid);
266
267         if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
268             tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
269                 goto rtattr_failure;
270
271         rta->rta_len = (skb->tail - b);
272         return skb->len;
273
274 rtattr_failure:
275         skb_trim(skb, b - skb->data);
276         return -1;
277 }
278
279 static struct tcf_proto_ops cls_basic_ops = {
280         .kind           =       "basic",
281         .classify       =       basic_classify,
282         .init           =       basic_init,
283         .destroy        =       basic_destroy,
284         .get            =       basic_get,
285         .put            =       basic_put,
286         .change         =       basic_change,
287         .delete         =       basic_delete,
288         .walk           =       basic_walk,
289         .dump           =       basic_dump,
290         .owner          =       THIS_MODULE,
291 };
292
293 static int __init init_basic(void)
294 {
295         return register_tcf_proto_ops(&cls_basic_ops);
296 }
297
298 static void __exit exit_basic(void) 
299 {
300         unregister_tcf_proto_ops(&cls_basic_ops);
301 }
302
303 module_init(init_basic)
304 module_exit(exit_basic)
305 MODULE_LICENSE("GPL");
306