xref: /openbmc/linux/net/sched/cls_fw.c (revision e868d61272caa648214046a096e5a6bfc068dc8c)
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/module.h>
22 #include <asm/uaccess.h>
23 #include <asm/system.h>
24 #include <linux/bitops.h>
25 #include <linux/types.h>
26 #include <linux/kernel.h>
27 #include <linux/string.h>
28 #include <linux/mm.h>
29 #include <linux/socket.h>
30 #include <linux/sockios.h>
31 #include <linux/in.h>
32 #include <linux/errno.h>
33 #include <linux/interrupt.h>
34 #include <linux/if_ether.h>
35 #include <linux/inet.h>
36 #include <linux/netdevice.h>
37 #include <linux/etherdevice.h>
38 #include <linux/notifier.h>
39 #include <linux/netfilter.h>
40 #include <net/ip.h>
41 #include <net/netlink.h>
42 #include <net/route.h>
43 #include <linux/skbuff.h>
44 #include <net/sock.h>
45 #include <net/act_api.h>
46 #include <net/pkt_cls.h>
47 
48 #define HTSIZE (PAGE_SIZE/sizeof(struct fw_filter *))
49 
50 struct fw_head
51 {
52 	struct fw_filter *ht[HTSIZE];
53 	u32 mask;
54 };
55 
56 struct fw_filter
57 {
58 	struct fw_filter	*next;
59 	u32			id;
60 	struct tcf_result	res;
61 #ifdef CONFIG_NET_CLS_IND
62 	char			indev[IFNAMSIZ];
63 #endif /* CONFIG_NET_CLS_IND */
64 	struct tcf_exts		exts;
65 };
66 
67 static struct tcf_ext_map fw_ext_map = {
68 	.action = TCA_FW_ACT,
69 	.police = TCA_FW_POLICE
70 };
71 
72 static __inline__ int fw_hash(u32 handle)
73 {
74 	if (HTSIZE == 4096)
75 		return ((handle >> 24) & 0xFFF) ^
76 		       ((handle >> 12) & 0xFFF) ^
77 		       (handle & 0xFFF);
78 	else if (HTSIZE == 2048)
79 		return ((handle >> 22) & 0x7FF) ^
80 		       ((handle >> 11) & 0x7FF) ^
81 		       (handle & 0x7FF);
82 	else if (HTSIZE == 1024)
83 		return ((handle >> 20) & 0x3FF) ^
84 		       ((handle >> 10) & 0x3FF) ^
85 		       (handle & 0x3FF);
86 	else if (HTSIZE == 512)
87 		return (handle >> 27) ^
88 		       ((handle >> 18) & 0x1FF) ^
89 		       ((handle >> 9) & 0x1FF) ^
90 		       (handle & 0x1FF);
91 	else if (HTSIZE == 256) {
92 		u8 *t = (u8 *) &handle;
93 		return t[0] ^ t[1] ^ t[2] ^ t[3];
94 	} else
95 		return handle & (HTSIZE - 1);
96 }
97 
98 static int fw_classify(struct sk_buff *skb, struct tcf_proto *tp,
99 			  struct tcf_result *res)
100 {
101 	struct fw_head *head = (struct fw_head*)tp->root;
102 	struct fw_filter *f;
103 	int r;
104 	u32 id = skb->mark;
105 
106 	if (head != NULL) {
107 		id &= head->mask;
108 		for (f=head->ht[fw_hash(id)]; f; f=f->next) {
109 			if (f->id == id) {
110 				*res = f->res;
111 #ifdef CONFIG_NET_CLS_IND
112 				if (!tcf_match_indev(skb, f->indev))
113 					continue;
114 #endif /* CONFIG_NET_CLS_IND */
115 				r = tcf_exts_exec(skb, &f->exts, res);
116 				if (r < 0)
117 					continue;
118 
119 				return r;
120 			}
121 		}
122 	} else {
123 		/* old method */
124 		if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) {
125 			res->classid = id;
126 			res->class = 0;
127 			return 0;
128 		}
129 	}
130 
131 	return -1;
132 }
133 
134 static unsigned long fw_get(struct tcf_proto *tp, u32 handle)
135 {
136 	struct fw_head *head = (struct fw_head*)tp->root;
137 	struct fw_filter *f;
138 
139 	if (head == NULL)
140 		return 0;
141 
142 	for (f=head->ht[fw_hash(handle)]; f; f=f->next) {
143 		if (f->id == handle)
144 			return (unsigned long)f;
145 	}
146 	return 0;
147 }
148 
149 static void fw_put(struct tcf_proto *tp, unsigned long f)
150 {
151 }
152 
153 static int fw_init(struct tcf_proto *tp)
154 {
155 	return 0;
156 }
157 
158 static inline void
159 fw_delete_filter(struct tcf_proto *tp, struct fw_filter *f)
160 {
161 	tcf_unbind_filter(tp, &f->res);
162 	tcf_exts_destroy(tp, &f->exts);
163 	kfree(f);
164 }
165 
166 static void fw_destroy(struct tcf_proto *tp)
167 {
168 	struct fw_head *head = (struct fw_head*)xchg(&tp->root, NULL);
169 	struct fw_filter *f;
170 	int h;
171 
172 	if (head == NULL)
173 		return;
174 
175 	for (h=0; h<HTSIZE; h++) {
176 		while ((f=head->ht[h]) != NULL) {
177 			head->ht[h] = f->next;
178 			fw_delete_filter(tp, f);
179 		}
180 	}
181 	kfree(head);
182 }
183 
184 static int fw_delete(struct tcf_proto *tp, unsigned long arg)
185 {
186 	struct fw_head *head = (struct fw_head*)tp->root;
187 	struct fw_filter *f = (struct fw_filter*)arg;
188 	struct fw_filter **fp;
189 
190 	if (head == NULL || f == NULL)
191 		goto out;
192 
193 	for (fp=&head->ht[fw_hash(f->id)]; *fp; fp = &(*fp)->next) {
194 		if (*fp == f) {
195 			tcf_tree_lock(tp);
196 			*fp = f->next;
197 			tcf_tree_unlock(tp);
198 			fw_delete_filter(tp, f);
199 			return 0;
200 		}
201 	}
202 out:
203 	return -EINVAL;
204 }
205 
206 static int
207 fw_change_attrs(struct tcf_proto *tp, struct fw_filter *f,
208 	struct rtattr **tb, struct rtattr **tca, unsigned long base)
209 {
210 	struct fw_head *head = (struct fw_head *)tp->root;
211 	struct tcf_exts e;
212 	u32 mask;
213 	int err;
214 
215 	err = tcf_exts_validate(tp, tb, tca[TCA_RATE-1], &e, &fw_ext_map);
216 	if (err < 0)
217 		return err;
218 
219 	err = -EINVAL;
220 	if (tb[TCA_FW_CLASSID-1]) {
221 		if (RTA_PAYLOAD(tb[TCA_FW_CLASSID-1]) != sizeof(u32))
222 			goto errout;
223 		f->res.classid = *(u32*)RTA_DATA(tb[TCA_FW_CLASSID-1]);
224 		tcf_bind_filter(tp, &f->res, base);
225 	}
226 
227 #ifdef CONFIG_NET_CLS_IND
228 	if (tb[TCA_FW_INDEV-1]) {
229 		err = tcf_change_indev(tp, f->indev, tb[TCA_FW_INDEV-1]);
230 		if (err < 0)
231 			goto errout;
232 	}
233 #endif /* CONFIG_NET_CLS_IND */
234 
235 	if (tb[TCA_FW_MASK-1]) {
236 		if (RTA_PAYLOAD(tb[TCA_FW_MASK-1]) != sizeof(u32))
237 			goto errout;
238 		mask = *(u32*)RTA_DATA(tb[TCA_FW_MASK-1]);
239 		if (mask != head->mask)
240 			goto errout;
241 	} else if (head->mask != 0xFFFFFFFF)
242 		goto errout;
243 
244 	tcf_exts_change(tp, &f->exts, &e);
245 
246 	return 0;
247 errout:
248 	tcf_exts_destroy(tp, &e);
249 	return err;
250 }
251 
252 static int fw_change(struct tcf_proto *tp, unsigned long base,
253 		     u32 handle,
254 		     struct rtattr **tca,
255 		     unsigned long *arg)
256 {
257 	struct fw_head *head = (struct fw_head*)tp->root;
258 	struct fw_filter *f = (struct fw_filter *) *arg;
259 	struct rtattr *opt = tca[TCA_OPTIONS-1];
260 	struct rtattr *tb[TCA_FW_MAX];
261 	int err;
262 
263 	if (!opt)
264 		return handle ? -EINVAL : 0;
265 
266 	if (rtattr_parse_nested(tb, TCA_FW_MAX, opt) < 0)
267 		return -EINVAL;
268 
269 	if (f != NULL) {
270 		if (f->id != handle && handle)
271 			return -EINVAL;
272 		return fw_change_attrs(tp, f, tb, tca, base);
273 	}
274 
275 	if (!handle)
276 		return -EINVAL;
277 
278 	if (head == NULL) {
279 		u32 mask = 0xFFFFFFFF;
280 		if (tb[TCA_FW_MASK-1]) {
281 			if (RTA_PAYLOAD(tb[TCA_FW_MASK-1]) != sizeof(u32))
282 				return -EINVAL;
283 			mask = *(u32*)RTA_DATA(tb[TCA_FW_MASK-1]);
284 		}
285 
286 		head = kzalloc(sizeof(struct fw_head), GFP_KERNEL);
287 		if (head == NULL)
288 			return -ENOBUFS;
289 		head->mask = mask;
290 
291 		tcf_tree_lock(tp);
292 		tp->root = head;
293 		tcf_tree_unlock(tp);
294 	}
295 
296 	f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL);
297 	if (f == NULL)
298 		return -ENOBUFS;
299 
300 	f->id = handle;
301 
302 	err = fw_change_attrs(tp, f, tb, tca, base);
303 	if (err < 0)
304 		goto errout;
305 
306 	f->next = head->ht[fw_hash(handle)];
307 	tcf_tree_lock(tp);
308 	head->ht[fw_hash(handle)] = f;
309 	tcf_tree_unlock(tp);
310 
311 	*arg = (unsigned long)f;
312 	return 0;
313 
314 errout:
315 	kfree(f);
316 	return err;
317 }
318 
319 static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg)
320 {
321 	struct fw_head *head = (struct fw_head*)tp->root;
322 	int h;
323 
324 	if (head == NULL)
325 		arg->stop = 1;
326 
327 	if (arg->stop)
328 		return;
329 
330 	for (h = 0; h < HTSIZE; h++) {
331 		struct fw_filter *f;
332 
333 		for (f = head->ht[h]; f; f = f->next) {
334 			if (arg->count < arg->skip) {
335 				arg->count++;
336 				continue;
337 			}
338 			if (arg->fn(tp, (unsigned long)f, arg) < 0) {
339 				arg->stop = 1;
340 				return;
341 			}
342 			arg->count++;
343 		}
344 	}
345 }
346 
347 static int fw_dump(struct tcf_proto *tp, unsigned long fh,
348 		   struct sk_buff *skb, struct tcmsg *t)
349 {
350 	struct fw_head *head = (struct fw_head *)tp->root;
351 	struct fw_filter *f = (struct fw_filter*)fh;
352 	unsigned char *b = skb_tail_pointer(skb);
353 	struct rtattr *rta;
354 
355 	if (f == NULL)
356 		return skb->len;
357 
358 	t->tcm_handle = f->id;
359 
360 	if (!f->res.classid && !tcf_exts_is_available(&f->exts))
361 		return skb->len;
362 
363 	rta = (struct rtattr*)b;
364 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
365 
366 	if (f->res.classid)
367 		RTA_PUT(skb, TCA_FW_CLASSID, 4, &f->res.classid);
368 #ifdef CONFIG_NET_CLS_IND
369 	if (strlen(f->indev))
370 		RTA_PUT(skb, TCA_FW_INDEV, IFNAMSIZ, f->indev);
371 #endif /* CONFIG_NET_CLS_IND */
372 	if (head->mask != 0xFFFFFFFF)
373 		RTA_PUT(skb, TCA_FW_MASK, 4, &head->mask);
374 
375 	if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
376 		goto rtattr_failure;
377 
378 	rta->rta_len = skb_tail_pointer(skb) - b;
379 
380 	if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
381 		goto rtattr_failure;
382 
383 	return skb->len;
384 
385 rtattr_failure:
386 	nlmsg_trim(skb, b);
387 	return -1;
388 }
389 
390 static struct tcf_proto_ops cls_fw_ops = {
391 	.next		=	NULL,
392 	.kind		=	"fw",
393 	.classify	=	fw_classify,
394 	.init		=	fw_init,
395 	.destroy	=	fw_destroy,
396 	.get		=	fw_get,
397 	.put		=	fw_put,
398 	.change		=	fw_change,
399 	.delete		=	fw_delete,
400 	.walk		=	fw_walk,
401 	.dump		=	fw_dump,
402 	.owner		=	THIS_MODULE,
403 };
404 
405 static int __init init_fw(void)
406 {
407 	return register_tcf_proto_ops(&cls_fw_ops);
408 }
409 
410 static void __exit exit_fw(void)
411 {
412 	unregister_tcf_proto_ops(&cls_fw_ops);
413 }
414 
415 module_init(init_fw)
416 module_exit(exit_fw)
417 MODULE_LICENSE("GPL");
418