aboutsummaryrefslogtreecommitdiff
path: root/net/sched/cls_basic.c
blob: 636d9131d87016a46597af5cadd3471d21e1798f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
/*
 * net/sched/cls_basic.c	Basic Packet Classifier.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 * Authors:	Thomas Graf <tgraf@suug.ch>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>

struct basic_head {
	u32			hgenerator;
	struct list_head	flist;
};

struct basic_filter {
	u32			handle;
	struct tcf_exts		exts;
	struct tcf_ematch_tree	ematches;
	struct tcf_result	res;
	struct list_head	link;
};

static const struct tcf_ext_map basic_ext_map = {
	.action = TCA_BASIC_ACT,
	.police = TCA_BASIC_POLICE
};

static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
			  struct tcf_result *res)
{
	int r;
	struct basic_head *head = (struct basic_head *) tp->root;
	struct basic_filter *f;

	list_for_each_entry(f, &head->flist, link) {
		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
			continue;
		*res = f->res;
		r = tcf_exts_exec(skb, &f->exts, res);
		if (r < 0)
			continue;
		return r;
	}
	return -1;
}

static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
{
	unsigned long l = 0UL;
	struct basic_head *head = (struct basic_head *) tp->root;
	struct basic_filter *f;

	if (head == NULL)
		return 0UL;

	list_for_each_entry(f, &head->flist, link)
		if (f->handle == handle)
			l = (unsigned long) f;

	return l;
}

static void basic_put(struct tcf_proto *tp, unsigned long f)
{
}

static int basic_init(struct tcf_proto *tp)
{
	struct basic_head *head;

	head = kzalloc(sizeof(*head), GFP_KERNEL);
	if (head == NULL)
		return -ENOBUFS;
	INIT_LIST_HEAD(&head->flist);
	tp->root = head;
	return 0;
}

static void basic_delete_filter(struct tcf_proto *tp, struct basic_filter *f)
{
	tcf_unbind_filter(tp, &f->res);
	tcf_exts_destroy(tp, &f->exts);
	tcf_em_tree_destroy(tp, &f->ematches);
	kfree(f);
}

static void basic_destroy(struct tcf_proto *tp)
{
	struct basic_head *head = tp->root;
	struct basic_filter *f, *n;

	list_for_each_entry_safe(f, n, &head->flist, link) {
		list_del(&f->link);
		basic_delete_filter(tp, f);
	}
	kfree(head);
}

static int basic_delete(struct tcf_proto *tp, unsigned long arg)
{
	struct basic_head *head = (struct basic_head *) tp->root;
	struct basic_filter *t, *f = (struct basic_filter *) arg;

	list_for_each_entry(t, &head->flist, link)
		if (t == f) {
			tcf_tree_lock(tp);
			list_del(&t->link);
			tcf_tree_unlock(tp);
			basic_delete_filter(tp, t);
			return 0;
		}

	return -ENOENT;
}

static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
	[TCA_BASIC_CLASSID]	= { .type = NLA_U32 },
	[TCA_BASIC_EMATCHES]	= { .type = NLA_NESTED },
};

static int basic_set_parms(struct net *net, struct tcf_proto *tp,
			   struct basic_filter *f, unsigned long base,
			   struct nlattr **tb,
			   struct nlattr *est)
{
	int err;
	struct tcf_exts e;
	struct tcf_ematch_tree t;

	err = tcf_exts_validate(net, tp, tb, est, &e, &basic_ext_map);
	if (err < 0)
		return err;

	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
	if (err < 0)
		goto errout;

	if (tb[TCA_BASIC_CLASSID]) {
		f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
		tcf_bind_filter(tp, &f->res, base);
	}

	tcf_exts_change(tp, &f->exts, &e);
	tcf_em_tree_change(tp, &f->ematches, &t);

	return 0;
errout:
	tcf_exts_destroy(tp, &e);
	return err;
}

static int basic_change(struct net *net, struct sk_buff *in_skb,
			struct tcf_proto *tp, unsigned long base, u32 handle,
			struct nlattr **tca, unsigned long *arg)
{
	int err;
	struct basic_head *head = (struct basic_head *) tp->root;
	struct nlattr *tb[TCA_BASIC_MAX + 1];
	struct basic_filter *f = (struct basic_filter *) *arg;

	if (tca[TCA_OPTIONS] == NULL)
		return -EINVAL;

	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
			       basic_policy);
	if (err < 0)
		return err;

	if (f != NULL) {
		if (handle && f->handle != handle)
			return -EINVAL;
		return basic_set_parms(net, tp, f, base, tb, tca[TCA_RATE]);
	}

	err = -ENOBUFS;
	f = kzalloc(sizeof(*f), GFP_KERNEL);
	if (f == NULL)
		goto errout;

	err = -EINVAL;
	if (handle)
		f->handle = handle;
	else {
		unsigned int i = 0x80000000;
		do {
			if (++head->hgenerator == 0x7FFFFFFF)
				head->hgenerator = 1;
		} while (--i > 0 && basic_get(tp, head->hgenerator));

		if (i <= 0) {
			pr_err("Insufficient number of handles\n");
			goto errout;
		}

		f->handle = head->hgenerator;
	}

	err = basic_set_parms(net, tp, f, base, tb, tca[TCA_RATE]);
	if (err < 0)
		goto errout;

	tcf_tree_lock(tp);
	list_add(&f->link, &head->flist);
	tcf_tree_unlock(tp);
	*arg = (unsigned long) f;

	return 0;
errout:
	if (*arg == 0UL && f)
		kfree(f);

	return err;
}

static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
	struct basic_head *head = (struct basic_head *) tp->root;
	struct basic_filter *f;

	list_for_each_entry(f, &head->flist, link) {
		if (arg->count < arg->skip)
			goto skip;

		if (arg->fn(tp, (unsigned long) f, arg) < 0) {
			arg->stop = 1;
			break;
		}
skip:
		arg->count++;
	}
}

static int basic_dump(struct tcf_proto *tp, unsigned long fh,
		      struct sk_buff *skb, struct tcmsg *t)
{
	struct basic_filter *f = (struct basic_filter *) fh;
	struct nlattr *nest;

	if (f == NULL)
		return skb->len;

	t->tcm_handle = f->handle;

	nest = nla_nest_start(skb, TCA_OPTIONS);
	if (nest == NULL)
		goto nla_put_failure;

	if (f->res.classid &&
	    nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
		goto nla_put_failure;

	if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
		goto nla_put_failure;

	nla_nest_end(skb, nest);

	if (tcf_exts_dump_stats(skb, &f->exts, &basic_ext_map) < 0)
		goto nla_put_failure;

	return skb->len;

nla_put_failure:
	nla_nest_cancel(skb, nest);
	return -1;
}

static struct tcf_proto_ops cls_basic_ops __read_mostly = {
	.kind		=	"basic",
	.classify	=	basic_classify,
	.init		=	basic_init,
	.destroy	=	basic_destroy,
	.get		=	basic_get,
	.put		=	basic_put,
	.change		=	basic_change,
	.delete		=	basic_delete,
	.walk		=	basic_walk,
	.dump		=	basic_dump,
	.owner		=	THIS_MODULE,
};

static int __init init_basic(void)
{
	return register_tcf_proto_ops(&cls_basic_ops);
}

static void __exit exit_basic(void)
{
	unregister_tcf_proto_ops(&cls_basic_ops);
}

module_init(init_basic)
module_exit(exit_basic)
MODULE_LICENSE("GPL");