xref: /openbmc/linux/net/sched/cls_fw.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * net/sched/cls_fw.c	Classifier mapping ipchains' fwmark to traffic class.
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:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10  *
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
15  *
16  * JHS: We should remove the CONFIG_NET_CLS_IND from here
17  * eventually when the meta match extension is made available
18  *
19  */
20 
21 #include <linux/config.h>
22 #include <linux/module.h>
23 #include <asm/uaccess.h>
24 #include <asm/system.h>
25 #include <linux/bitops.h>
26 #include <linux/types.h>
27 #include <linux/kernel.h>
28 #include <linux/sched.h>
29 #include <linux/string.h>
30 #include <linux/mm.h>
31 #include <linux/socket.h>
32 #include <linux/sockios.h>
33 #include <linux/in.h>
34 #include <linux/errno.h>
35 #include <linux/interrupt.h>
36 #include <linux/if_ether.h>
37 #include <linux/inet.h>
38 #include <linux/netdevice.h>
39 #include <linux/etherdevice.h>
40 #include <linux/notifier.h>
41 #include <linux/netfilter.h>
42 #include <net/ip.h>
43 #include <net/route.h>
44 #include <linux/skbuff.h>
45 #include <net/sock.h>
46 #include <net/act_api.h>
47 #include <net/pkt_cls.h>
48 
49 struct fw_head
50 {
51 	struct fw_filter *ht[256];
52 };
53 
54 struct fw_filter
55 {
56 	struct fw_filter	*next;
57 	u32			id;
58 	struct tcf_result	res;
59 #ifdef CONFIG_NET_CLS_IND
60 	char			indev[IFNAMSIZ];
61 #endif /* CONFIG_NET_CLS_IND */
62 	struct tcf_exts		exts;
63 };
64 
65 static struct tcf_ext_map fw_ext_map = {
66 	.action = TCA_FW_ACT,
67 	.police = TCA_FW_POLICE
68 };
69 
70 static __inline__ int fw_hash(u32 handle)
71 {
72 	return handle&0xFF;
73 }
74 
75 static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
76 			  struct tcf_result *res)
77 {
78 	struct fw_head *head = (struct fw_head*)tp->root;
79 	struct fw_filter *f;
80 	int r;
81 #ifdef CONFIG_NETFILTER
82 	u32 id = skb->nfmark;
83 #else
84 	u32 id = 0;
85 #endif
86 
87 	if (head != NULL) {
88 		for (f=head->ht[fw_hash(id)]; f; f=f->next) {
89 			if (f->id == id) {
90 				*res = f->res;
91 #ifdef CONFIG_NET_CLS_IND
92 				if (!tcf_match_indev(skb, f->indev))
93 					continue;
94 #endif /* CONFIG_NET_CLS_IND */
95 				r = tcf_exts_exec(skb, &f->exts, res);
96 				if (r < 0)
97 					continue;
98 
99 				return r;
100 			}
101 		}
102 	} else {
103 		/* old method */
104 		if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
105 			res->classid = id;
106 			res->class = 0;
107 			return 0;
108 		}
109 	}
110 
111 	return -1;
112 }
113 
114 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
115 {
116 	struct fw_head *head = (struct fw_head*)tp->root;
117 	struct fw_filter *f;
118 
119 	if (head == NULL)
120 		return 0;
121 
122 	for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
123 		if (f->id == handle)
124 			return (unsigned long)f;
125 	}
126 	return 0;
127 }
128 
129 static void fw_put(struct tcf_proto *tp, unsigned long f)
130 {
131 }
132 
133 static int fw_init(struct tcf_proto *tp)
134 {
135 	return 0;
136 }
137 
138 static inline void
139 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
140 {
141 	tcf_unbind_filter(tp, &f->res);
142 	tcf_exts_destroy(tp, &f->exts);
143 	kfree(f);
144 }
145 
146 static void fw_destroy(struct tcf_proto *tp)
147 {
148 	struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
149 	struct fw_filter *f;
150 	int h;
151 
152 	if (head == NULL)
153 		return;
154 
155 	for (h=0; h<256; h++) {
156 		while ((f=head->ht[h]) != NULL) {
157 			head->ht[h] = f->next;
158 			fw_delete_filter(tp, f);
159 		}
160 	}
161 	kfree(head);
162 }
163 
164 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
165 {
166 	struct fw_head *head = (struct fw_head*)tp->root;
167 	struct fw_filter *f = (struct fw_filter*)arg;
168 	struct fw_filter **fp;
169 
170 	if (head == NULL || f == NULL)
171 		goto out;
172 
173 	for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
174 		if (*fp == f) {
175 			tcf_tree_lock(tp);
176 			*fp = f->next;
177 			tcf_tree_unlock(tp);
178 			fw_delete_filter(tp, f);
179 			return 0;
180 		}
181 	}
182 out:
183 	return -EINVAL;
184 }
185 
186 static int
187 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
188 	struct rtattr **tb, struct rtattr **tca, unsigned long base)
189 {
190 	struct tcf_exts e;
191 	int err;
192 
193 	err = tcf_exts_validate(tp, tb, tca[TCA_RATE-1], &e, &fw_ext_map);
194 	if (err < 0)
195 		return err;
196 
197 	err = -EINVAL;
198 	if (tb[TCA_FW_CLASSID-1]) {
199 		if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != sizeof(u32))
200 			goto errout;
201 		f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
202 		tcf_bind_filter(tp, &f->res, base);
203 	}
204 
205 #ifdef CONFIG_NET_CLS_IND
206 	if (tb[TCA_FW_INDEV-1]) {
207 		err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV-1]);
208 		if (err < 0)
209 			goto errout;
210 	}
211 #endif /* CONFIG_NET_CLS_IND */
212 
213 	tcf_exts_change(tp, &f->exts, &e);
214 
215 	return 0;
216 errout:
217 	tcf_exts_destroy(tp, &e);
218 	return err;
219 }
220 
221 static int fw_change(struct tcf_proto *tp, unsigned long base,
222 		     u32 handle,
223 		     struct rtattr **tca,
224 		     unsigned long *arg)
225 {
226 	struct fw_head *head = (struct fw_head*)tp->root;
227 	struct fw_filter *f = (struct fw_filter *) *arg;
228 	struct rtattr *opt = tca[TCA_OPTIONS-1];
229 	struct rtattr *tb[TCA_FW_MAX];
230 	int err;
231 
232 	if (!opt)
233 		return handle ? -EINVAL : 0;
234 
235 	if (rtattr_parse_nested(tb, TCA_FW_MAX, opt) < 0)
236 		return -EINVAL;
237 
238 	if (f != NULL) {
239 		if (f->id != handle && handle)
240 			return -EINVAL;
241 		return fw_change_attrs(tp, f, tb, tca, base);
242 	}
243 
244 	if (!handle)
245 		return -EINVAL;
246 
247 	if (head == NULL) {
248 		head = kmalloc(sizeof(struct fw_head), GFP_KERNEL);
249 		if (head == NULL)
250 			return -ENOBUFS;
251 		memset(head, 0, sizeof(*head));
252 
253 		tcf_tree_lock(tp);
254 		tp->root = head;
255 		tcf_tree_unlock(tp);
256 	}
257 
258 	f = kmalloc(sizeof(struct fw_filter), GFP_KERNEL);
259 	if (f == NULL)
260 		return -ENOBUFS;
261 	memset(f, 0, sizeof(*f));
262 
263 	f->id = handle;
264 
265 	err = fw_change_attrs(tp, f, tb, tca, base);
266 	if (err < 0)
267 		goto errout;
268 
269 	f->next = head->ht[fw_hash(handle)];
270 	tcf_tree_lock(tp);
271 	head->ht[fw_hash(handle)] = f;
272 	tcf_tree_unlock(tp);
273 
274 	*arg = (unsigned long)f;
275 	return 0;
276 
277 errout:
278 	if (f)
279 		kfree(f);
280 	return err;
281 }
282 
283 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
284 {
285 	struct fw_head *head = (struct fw_head*)tp->root;
286 	int h;
287 
288 	if (head == NULL)
289 		arg->stop = 1;
290 
291 	if (arg->stop)
292 		return;
293 
294 	for (h = 0; h < 256; h++) {
295 		struct fw_filter *f;
296 
297 		for (f = head->ht[h]; f; f = f->next) {
298 			if (arg->count < arg->skip) {
299 				arg->count++;
300 				continue;
301 			}
302 			if (arg->fn(tp, (unsigned long)f, arg) < 0) {
303 				arg->stop = 1;
304 				return;
305 			}
306 			arg->count++;
307 		}
308 	}
309 }
310 
311 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
312 		   struct sk_buff *skb, struct tcmsg *t)
313 {
314 	struct fw_filter *f = (struct fw_filter*)fh;
315 	unsigned char	 *b = skb->tail;
316 	struct rtattr *rta;
317 
318 	if (f == NULL)
319 		return skb->len;
320 
321 	t->tcm_handle = f->id;
322 
323 	if (!f->res.classid && !tcf_exts_is_available(&f->exts))
324 		return skb->len;
325 
326 	rta = (struct rtattr*)b;
327 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
328 
329 	if (f->res.classid)
330 		RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
331 #ifdef CONFIG_NET_CLS_IND
332 	if (strlen(f->indev))
333 		RTA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
334 #endif /* CONFIG_NET_CLS_IND */
335 
336 	if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
337 		goto rtattr_failure;
338 
339 	rta->rta_len = skb->tail - b;
340 
341 	if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
342 		goto rtattr_failure;
343 
344 	return skb->len;
345 
346 rtattr_failure:
347 	skb_trim(skb, b - skb->data);
348 	return -1;
349 }
350 
351 static struct tcf_proto_ops cls_fw_ops = {
352 	.next		=	NULL,
353 	.kind		=	"fw",
354 	.classify	=	fw_classify,
355 	.init		=	fw_init,
356 	.destroy	=	fw_destroy,
357 	.get		=	fw_get,
358 	.put		=	fw_put,
359 	.change		=	fw_change,
360 	.delete		=	fw_delete,
361 	.walk		=	fw_walk,
362 	.dump		=	fw_dump,
363 	.owner		=	THIS_MODULE,
364 };
365 
366 static int __init init_fw(void)
367 {
368 	return register_tcf_proto_ops(&cls_fw_ops);
369 }
370 
371 static void __exit exit_fw(void)
372 {
373 	unregister_tcf_proto_ops(&cls_fw_ops);
374 }
375 
376 module_init(init_fw)
377 module_exit(exit_fw)
378 MODULE_LICENSE("GPL");
379