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
50struct fw_head
51{
52	struct fw_filter *ht[HTSIZE];
53	u32 mask;
54};
55
56struct 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
67static struct tcf_ext_map fw_ext_map = {
68	.action = TCA_FW_ACT,
69	.police = TCA_FW_POLICE
70};
71
72static __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
98static 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
134static 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
149static void fw_put(struct tcf_proto *tp, unsigned long f)
150{
151}
152
153static int fw_init(struct tcf_proto *tp)
154{
155	return 0;
156}
157
158static inline void
159fw_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
166static 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
184static 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	}
202out:
203	return -EINVAL;
204}
205
206static int
207fw_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;
247errout:
248	tcf_exts_destroy(tp, &e);
249	return err;
250}
251
252static 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
314errout:
315	kfree(f);
316	return err;
317}
318
319static 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
347static 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
385rtattr_failure:
386	nlmsg_trim(skb, b);
387	return -1;
388}
389
390static 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
405static int __init init_fw(void)
406{
407	return register_tcf_proto_ops(&cls_fw_ops);
408}
409
410static void __exit exit_fw(void)
411{
412	unregister_tcf_proto_ops(&cls_fw_ops);
413}
414
415module_init(init_fw)
416module_exit(exit_fw)
417MODULE_LICENSE("GPL");
418