sched, cls: check if we could overwrite actions when changing a filter
[linux/fpc-iii.git] / net / sched / cls_fw.c
blob861b03ccfed0a55007ceb001a297b05906b36ed3
1 /*
2 * net/sched/cls_fw.c Classifier mapping ipchains' fwmark to traffic class.
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.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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
16 * JHS: We should remove the CONFIG_NET_CLS_IND from here
17 * eventually when the meta match extension is made available
21 #include <linux/module.h>
22 #include <linux/slab.h>
23 #include <linux/types.h>
24 #include <linux/kernel.h>
25 #include <linux/string.h>
26 #include <linux/errno.h>
27 #include <linux/skbuff.h>
28 #include <net/netlink.h>
29 #include <net/act_api.h>
30 #include <net/pkt_cls.h>
32 #define HTSIZE 256
34 struct fw_head {
35 u32 mask;
36 struct fw_filter *ht[HTSIZE];
39 struct fw_filter {
40 struct fw_filter *next;
41 u32 id;
42 struct tcf_result res;
43 #ifdef CONFIG_NET_CLS_IND
44 int ifindex;
45 #endif /* CONFIG_NET_CLS_IND */
46 struct tcf_exts exts;
49 static u32 fw_hash(u32 handle)
51 handle ^= (handle >> 16);
52 handle ^= (handle >> 8);
53 return handle % HTSIZE;
56 static int fw_classify(struct sk_buff *skb, const struct tcf_proto *tp,
57 struct tcf_result *res)
59 struct fw_head *head = tp->root;
60 struct fw_filter *f;
61 int r;
62 u32 id = skb->mark;
64 if (head != NULL) {
65 id &= head->mask;
66 for (f = head->ht[fw_hash(id)]; f; f = f->next) {
67 if (f->id == id) {
68 *res = f->res;
69 #ifdef CONFIG_NET_CLS_IND
70 if (!tcf_match_indev(skb, f->ifindex))
71 continue;
72 #endif /* CONFIG_NET_CLS_IND */
73 r = tcf_exts_exec(skb, &f->exts, res);
74 if (r < 0)
75 continue;
77 return r;
80 } else {
81 /* old method */
82 if (id && (TC_H_MAJ(id) == 0 ||
83 !(TC_H_MAJ(id ^ tp->q->handle)))) {
84 res->classid = id;
85 res->class = 0;
86 return 0;
90 return -1;
93 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
95 struct fw_head *head = tp->root;
96 struct fw_filter *f;
98 if (head == NULL)
99 return 0;
101 for (f = head->ht[fw_hash(handle)]; f; f = f->next) {
102 if (f->id == handle)
103 return (unsigned long)f;
105 return 0;
108 static void fw_put(struct tcf_proto *tp, unsigned long f)
112 static int fw_init(struct tcf_proto *tp)
114 return 0;
117 static void fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
119 tcf_unbind_filter(tp, &f->res);
120 tcf_exts_destroy(tp, &f->exts);
121 kfree(f);
124 static void fw_destroy(struct tcf_proto *tp)
126 struct fw_head *head = tp->root;
127 struct fw_filter *f;
128 int h;
130 if (head == NULL)
131 return;
133 for (h = 0; h < HTSIZE; h++) {
134 while ((f = head->ht[h]) != NULL) {
135 head->ht[h] = f->next;
136 fw_delete_filter(tp, f);
139 kfree(head);
142 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
144 struct fw_head *head = tp->root;
145 struct fw_filter *f = (struct fw_filter *)arg;
146 struct fw_filter **fp;
148 if (head == NULL || f == NULL)
149 goto out;
151 for (fp = &head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
152 if (*fp == f) {
153 tcf_tree_lock(tp);
154 *fp = f->next;
155 tcf_tree_unlock(tp);
156 fw_delete_filter(tp, f);
157 return 0;
160 out:
161 return -EINVAL;
164 static const struct nla_policy fw_policy[TCA_FW_MAX + 1] = {
165 [TCA_FW_CLASSID] = { .type = NLA_U32 },
166 [TCA_FW_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ },
167 [TCA_FW_MASK] = { .type = NLA_U32 },
170 static int
171 fw_change_attrs(struct net *net, struct tcf_proto *tp, struct fw_filter *f,
172 struct nlattr **tb, struct nlattr **tca, unsigned long base, bool ovr)
174 struct fw_head *head = tp->root;
175 struct tcf_exts e;
176 u32 mask;
177 int err;
179 tcf_exts_init(&e, TCA_FW_ACT, TCA_FW_POLICE);
180 err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &e, ovr);
181 if (err < 0)
182 return err;
184 if (tb[TCA_FW_CLASSID]) {
185 f->res.classid = nla_get_u32(tb[TCA_FW_CLASSID]);
186 tcf_bind_filter(tp, &f->res, base);
189 #ifdef CONFIG_NET_CLS_IND
190 if (tb[TCA_FW_INDEV]) {
191 int ret;
192 ret = tcf_change_indev(net, tb[TCA_FW_INDEV]);
193 if (ret < 0) {
194 err = ret;
195 goto errout;
197 f->ifindex = ret;
199 #endif /* CONFIG_NET_CLS_IND */
201 err = -EINVAL;
202 if (tb[TCA_FW_MASK]) {
203 mask = nla_get_u32(tb[TCA_FW_MASK]);
204 if (mask != head->mask)
205 goto errout;
206 } else if (head->mask != 0xFFFFFFFF)
207 goto errout;
209 tcf_exts_change(tp, &f->exts, &e);
211 return 0;
212 errout:
213 tcf_exts_destroy(tp, &e);
214 return err;
217 static int fw_change(struct net *net, struct sk_buff *in_skb,
218 struct tcf_proto *tp, unsigned long base,
219 u32 handle,
220 struct nlattr **tca,
221 unsigned long *arg, bool ovr)
223 struct fw_head *head = tp->root;
224 struct fw_filter *f = (struct fw_filter *) *arg;
225 struct nlattr *opt = tca[TCA_OPTIONS];
226 struct nlattr *tb[TCA_FW_MAX + 1];
227 int err;
229 if (!opt)
230 return handle ? -EINVAL : 0;
232 err = nla_parse_nested(tb, TCA_FW_MAX, opt, fw_policy);
233 if (err < 0)
234 return err;
236 if (f != NULL) {
237 if (f->id != handle && handle)
238 return -EINVAL;
239 return fw_change_attrs(net, tp, f, tb, tca, base, ovr);
242 if (!handle)
243 return -EINVAL;
245 if (head == NULL) {
246 u32 mask = 0xFFFFFFFF;
247 if (tb[TCA_FW_MASK])
248 mask = nla_get_u32(tb[TCA_FW_MASK]);
250 head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
251 if (head == NULL)
252 return -ENOBUFS;
253 head->mask = mask;
255 tcf_tree_lock(tp);
256 tp->root = head;
257 tcf_tree_unlock(tp);
260 f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
261 if (f == NULL)
262 return -ENOBUFS;
264 tcf_exts_init(&f->exts, TCA_FW_ACT, TCA_FW_POLICE);
265 f->id = handle;
267 err = fw_change_attrs(net, tp, f, tb, tca, base, ovr);
268 if (err < 0)
269 goto errout;
271 f->next = head->ht[fw_hash(handle)];
272 tcf_tree_lock(tp);
273 head->ht[fw_hash(handle)] = f;
274 tcf_tree_unlock(tp);
276 *arg = (unsigned long)f;
277 return 0;
279 errout:
280 kfree(f);
281 return err;
284 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
286 struct fw_head *head = tp->root;
287 int h;
289 if (head == NULL)
290 arg->stop = 1;
292 if (arg->stop)
293 return;
295 for (h = 0; h < HTSIZE; h++) {
296 struct fw_filter *f;
298 for (f = head->ht[h]; f; f = f->next) {
299 if (arg->count < arg->skip) {
300 arg->count++;
301 continue;
303 if (arg->fn(tp, (unsigned long)f, arg) < 0) {
304 arg->stop = 1;
305 return;
307 arg->count++;
312 static int fw_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
313 struct sk_buff *skb, struct tcmsg *t)
315 struct fw_head *head = tp->root;
316 struct fw_filter *f = (struct fw_filter *)fh;
317 unsigned char *b = skb_tail_pointer(skb);
318 struct nlattr *nest;
320 if (f == NULL)
321 return skb->len;
323 t->tcm_handle = f->id;
325 if (!f->res.classid && !tcf_exts_is_available(&f->exts))
326 return skb->len;
328 nest = nla_nest_start(skb, TCA_OPTIONS);
329 if (nest == NULL)
330 goto nla_put_failure;
332 if (f->res.classid &&
333 nla_put_u32(skb, TCA_FW_CLASSID, f->res.classid))
334 goto nla_put_failure;
335 #ifdef CONFIG_NET_CLS_IND
336 if (f->ifindex) {
337 struct net_device *dev;
338 dev = __dev_get_by_index(net, f->ifindex);
339 if (dev && nla_put_string(skb, TCA_FW_INDEV, dev->name))
340 goto nla_put_failure;
342 #endif /* CONFIG_NET_CLS_IND */
343 if (head->mask != 0xFFFFFFFF &&
344 nla_put_u32(skb, TCA_FW_MASK, head->mask))
345 goto nla_put_failure;
347 if (tcf_exts_dump(skb, &f->exts) < 0)
348 goto nla_put_failure;
350 nla_nest_end(skb, nest);
352 if (tcf_exts_dump_stats(skb, &f->exts) < 0)
353 goto nla_put_failure;
355 return skb->len;
357 nla_put_failure:
358 nlmsg_trim(skb, b);
359 return -1;
362 static struct tcf_proto_ops cls_fw_ops __read_mostly = {
363 .kind = "fw",
364 .classify = fw_classify,
365 .init = fw_init,
366 .destroy = fw_destroy,
367 .get = fw_get,
368 .put = fw_put,
369 .change = fw_change,
370 .delete = fw_delete,
371 .walk = fw_walk,
372 .dump = fw_dump,
373 .owner = THIS_MODULE,
376 static int __init init_fw(void)
378 return register_tcf_proto_ops(&cls_fw_ops);
381 static void __exit exit_fw(void)
383 unregister_tcf_proto_ops(&cls_fw_ops);
386 module_init(init_fw)
387 module_exit(exit_fw)
388 MODULE_LICENSE("GPL");