Linux Audio

Check our new training course

Linux kernel drivers training

May 6-19, 2025
Register
Loading...
v3.1
  1/*
  2 * net/sched/cls_basic.c	Basic Packet Classifier.
  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:	Thomas Graf <tgraf@suug.ch>
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/slab.h>
 14#include <linux/types.h>
 15#include <linux/kernel.h>
 16#include <linux/string.h>
 17#include <linux/errno.h>
 18#include <linux/rtnetlink.h>
 19#include <linux/skbuff.h>
 20#include <net/netlink.h>
 21#include <net/act_api.h>
 22#include <net/pkt_cls.h>
 23
 24struct basic_head {
 25	u32			hgenerator;
 26	struct list_head	flist;
 
 27};
 28
 29struct basic_filter {
 30	u32			handle;
 31	struct tcf_exts		exts;
 32	struct tcf_ematch_tree	ematches;
 33	struct tcf_result	res;
 
 34	struct list_head	link;
 35};
 36
 37static const struct tcf_ext_map basic_ext_map = {
 38	.action = TCA_BASIC_ACT,
 39	.police = TCA_BASIC_POLICE
 40};
 41
 42static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 43			  struct tcf_result *res)
 44{
 45	int r;
 46	struct basic_head *head = (struct basic_head *) tp->root;
 47	struct basic_filter *f;
 48
 49	list_for_each_entry(f, &head->flist, link) {
 50		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
 51			continue;
 52		*res = f->res;
 53		r = tcf_exts_exec(skb, &f->exts, res);
 54		if (r < 0)
 55			continue;
 56		return r;
 57	}
 58	return -1;
 59}
 60
 61static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
 62{
 63	unsigned long l = 0UL;
 64	struct basic_head *head = (struct basic_head *) tp->root;
 65	struct basic_filter *f;
 66
 67	if (head == NULL)
 68		return 0UL;
 69
 70	list_for_each_entry(f, &head->flist, link)
 71		if (f->handle == handle)
 72			l = (unsigned long) f;
 
 
 
 73
 74	return l;
 75}
 76
 77static void basic_put(struct tcf_proto *tp, unsigned long f)
 78{
 79}
 80
 81static int basic_init(struct tcf_proto *tp)
 82{
 83	struct basic_head *head;
 84
 85	head = kzalloc(sizeof(*head), GFP_KERNEL);
 86	if (head == NULL)
 87		return -ENOBUFS;
 88	INIT_LIST_HEAD(&head->flist);
 89	tp->root = head;
 90	return 0;
 91}
 92
 93static void basic_delete_filter(struct tcf_proto *tp, struct basic_filter *f)
 94{
 95	tcf_unbind_filter(tp, &f->res);
 96	tcf_exts_destroy(tp, &f->exts);
 97	tcf_em_tree_destroy(tp, &f->ematches);
 
 98	kfree(f);
 99}
100
101static void basic_destroy(struct tcf_proto *tp)
102{
103	struct basic_head *head = tp->root;
104	struct basic_filter *f, *n;
105
 
 
 
106	list_for_each_entry_safe(f, n, &head->flist, link) {
107		list_del(&f->link);
108		basic_delete_filter(tp, f);
 
109	}
110	kfree(head);
 
111}
112
113static int basic_delete(struct tcf_proto *tp, unsigned long arg)
114{
115	struct basic_head *head = (struct basic_head *) tp->root;
116	struct basic_filter *t, *f = (struct basic_filter *) arg;
117
118	list_for_each_entry(t, &head->flist, link)
119		if (t == f) {
120			tcf_tree_lock(tp);
121			list_del(&t->link);
122			tcf_tree_unlock(tp);
123			basic_delete_filter(tp, t);
124			return 0;
125		}
126
127	return -ENOENT;
128}
129
130static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
131	[TCA_BASIC_CLASSID]	= { .type = NLA_U32 },
132	[TCA_BASIC_EMATCHES]	= { .type = NLA_NESTED },
133};
134
135static int basic_set_parms(struct tcf_proto *tp, struct basic_filter *f,
136			   unsigned long base, struct nlattr **tb,
137			   struct nlattr *est)
 
138{
139	int err = -EINVAL;
140	struct tcf_exts e;
141	struct tcf_ematch_tree t;
142
143	err = tcf_exts_validate(tp, tb, est, &e, &basic_ext_map);
144	if (err < 0)
145		return err;
 
 
 
146
147	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
148	if (err < 0)
149		goto errout;
150
151	if (tb[TCA_BASIC_CLASSID]) {
152		f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
153		tcf_bind_filter(tp, &f->res, base);
154	}
155
156	tcf_exts_change(tp, &f->exts, &e);
157	tcf_em_tree_change(tp, &f->ematches, &t);
 
158
159	return 0;
160errout:
161	tcf_exts_destroy(tp, &e);
162	return err;
163}
164
165static int basic_change(struct tcf_proto *tp, unsigned long base, u32 handle,
166			struct nlattr **tca, unsigned long *arg)
 
167{
168	int err;
169	struct basic_head *head = (struct basic_head *) tp->root;
170	struct nlattr *tb[TCA_BASIC_MAX + 1];
171	struct basic_filter *f = (struct basic_filter *) *arg;
 
172
173	if (tca[TCA_OPTIONS] == NULL)
174		return -EINVAL;
175
176	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
177			       basic_policy);
178	if (err < 0)
179		return err;
180
181	if (f != NULL) {
182		if (handle && f->handle != handle)
183			return -EINVAL;
184		return basic_set_parms(tp, f, base, tb, tca[TCA_RATE]);
185	}
186
187	err = -ENOBUFS;
188	f = kzalloc(sizeof(*f), GFP_KERNEL);
189	if (f == NULL)
 
 
 
190		goto errout;
191
192	err = -EINVAL;
193	if (handle)
194		f->handle = handle;
195	else {
 
 
196		unsigned int i = 0x80000000;
197		do {
198			if (++head->hgenerator == 0x7FFFFFFF)
199				head->hgenerator = 1;
200		} while (--i > 0 && basic_get(tp, head->hgenerator));
201
202		if (i <= 0) {
203			pr_err("Insufficient number of handles\n");
204			goto errout;
205		}
206
207		f->handle = head->hgenerator;
208	}
209
210	err = basic_set_parms(tp, f, base, tb, tca[TCA_RATE]);
211	if (err < 0)
212		goto errout;
213
214	tcf_tree_lock(tp);
215	list_add(&f->link, &head->flist);
216	tcf_tree_unlock(tp);
217	*arg = (unsigned long) f;
 
 
 
 
 
218
219	return 0;
220errout:
221	if (*arg == 0UL && f)
222		kfree(f);
223
224	return err;
225}
226
227static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
228{
229	struct basic_head *head = (struct basic_head *) tp->root;
230	struct basic_filter *f;
231
232	list_for_each_entry(f, &head->flist, link) {
233		if (arg->count < arg->skip)
234			goto skip;
235
236		if (arg->fn(tp, (unsigned long) f, arg) < 0) {
237			arg->stop = 1;
238			break;
239		}
240skip:
241		arg->count++;
242	}
243}
244
245static int basic_dump(struct tcf_proto *tp, unsigned long fh,
246		      struct sk_buff *skb, struct tcmsg *t)
247{
248	struct basic_filter *f = (struct basic_filter *) fh;
249	struct nlattr *nest;
250
251	if (f == NULL)
252		return skb->len;
253
254	t->tcm_handle = f->handle;
255
256	nest = nla_nest_start(skb, TCA_OPTIONS);
257	if (nest == NULL)
258		goto nla_put_failure;
259
260	if (f->res.classid)
261		NLA_PUT_U32(skb, TCA_BASIC_CLASSID, f->res.classid);
 
262
263	if (tcf_exts_dump(skb, &f->exts, &basic_ext_map) < 0 ||
264	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
265		goto nla_put_failure;
266
267	nla_nest_end(skb, nest);
268
269	if (tcf_exts_dump_stats(skb, &f->exts, &basic_ext_map) < 0)
270		goto nla_put_failure;
271
272	return skb->len;
273
274nla_put_failure:
275	nla_nest_cancel(skb, nest);
276	return -1;
277}
278
279static struct tcf_proto_ops cls_basic_ops __read_mostly = {
280	.kind		=	"basic",
281	.classify	=	basic_classify,
282	.init		=	basic_init,
283	.destroy	=	basic_destroy,
284	.get		=	basic_get,
285	.put		=	basic_put,
286	.change		=	basic_change,
287	.delete		=	basic_delete,
288	.walk		=	basic_walk,
289	.dump		=	basic_dump,
290	.owner		=	THIS_MODULE,
291};
292
293static int __init init_basic(void)
294{
295	return register_tcf_proto_ops(&cls_basic_ops);
296}
297
298static void __exit exit_basic(void)
299{
300	unregister_tcf_proto_ops(&cls_basic_ops);
301}
302
303module_init(init_basic)
304module_exit(exit_basic)
305MODULE_LICENSE("GPL");
306
v4.10.11
  1/*
  2 * net/sched/cls_basic.c	Basic Packet Classifier.
  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:	Thomas Graf <tgraf@suug.ch>
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/slab.h>
 14#include <linux/types.h>
 15#include <linux/kernel.h>
 16#include <linux/string.h>
 17#include <linux/errno.h>
 18#include <linux/rtnetlink.h>
 19#include <linux/skbuff.h>
 20#include <net/netlink.h>
 21#include <net/act_api.h>
 22#include <net/pkt_cls.h>
 23
 24struct basic_head {
 25	u32			hgenerator;
 26	struct list_head	flist;
 27	struct rcu_head		rcu;
 28};
 29
 30struct basic_filter {
 31	u32			handle;
 32	struct tcf_exts		exts;
 33	struct tcf_ematch_tree	ematches;
 34	struct tcf_result	res;
 35	struct tcf_proto	*tp;
 36	struct list_head	link;
 37	struct rcu_head		rcu;
 
 
 
 
 38};
 39
 40static int basic_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 41			  struct tcf_result *res)
 42{
 43	int r;
 44	struct basic_head *head = rcu_dereference_bh(tp->root);
 45	struct basic_filter *f;
 46
 47	list_for_each_entry_rcu(f, &head->flist, link) {
 48		if (!tcf_em_tree_match(skb, &f->ematches, NULL))
 49			continue;
 50		*res = f->res;
 51		r = tcf_exts_exec(skb, &f->exts, res);
 52		if (r < 0)
 53			continue;
 54		return r;
 55	}
 56	return -1;
 57}
 58
 59static unsigned long basic_get(struct tcf_proto *tp, u32 handle)
 60{
 61	unsigned long l = 0UL;
 62	struct basic_head *head = rtnl_dereference(tp->root);
 63	struct basic_filter *f;
 64
 65	list_for_each_entry(f, &head->flist, link) {
 66		if (f->handle == handle) {
 
 
 
 67			l = (unsigned long) f;
 68			break;
 69		}
 70	}
 71
 72	return l;
 73}
 74
 
 
 
 
 75static int basic_init(struct tcf_proto *tp)
 76{
 77	struct basic_head *head;
 78
 79	head = kzalloc(sizeof(*head), GFP_KERNEL);
 80	if (head == NULL)
 81		return -ENOBUFS;
 82	INIT_LIST_HEAD(&head->flist);
 83	rcu_assign_pointer(tp->root, head);
 84	return 0;
 85}
 86
 87static void basic_delete_filter(struct rcu_head *head)
 88{
 89	struct basic_filter *f = container_of(head, struct basic_filter, rcu);
 90
 91	tcf_exts_destroy(&f->exts);
 92	tcf_em_tree_destroy(&f->ematches);
 93	kfree(f);
 94}
 95
 96static bool basic_destroy(struct tcf_proto *tp, bool force)
 97{
 98	struct basic_head *head = rtnl_dereference(tp->root);
 99	struct basic_filter *f, *n;
100
101	if (!force && !list_empty(&head->flist))
102		return false;
103
104	list_for_each_entry_safe(f, n, &head->flist, link) {
105		list_del_rcu(&f->link);
106		tcf_unbind_filter(tp, &f->res);
107		call_rcu(&f->rcu, basic_delete_filter);
108	}
109	kfree_rcu(head, rcu);
110	return true;
111}
112
113static int basic_delete(struct tcf_proto *tp, unsigned long arg)
114{
115	struct basic_filter *f = (struct basic_filter *) arg;
 
116
117	list_del_rcu(&f->link);
118	tcf_unbind_filter(tp, &f->res);
119	call_rcu(&f->rcu, basic_delete_filter);
120	return 0;
 
 
 
 
 
 
121}
122
123static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
124	[TCA_BASIC_CLASSID]	= { .type = NLA_U32 },
125	[TCA_BASIC_EMATCHES]	= { .type = NLA_NESTED },
126};
127
128static int basic_set_parms(struct net *net, struct tcf_proto *tp,
129			   struct basic_filter *f, unsigned long base,
130			   struct nlattr **tb,
131			   struct nlattr *est, bool ovr)
132{
133	int err;
134	struct tcf_exts e;
135	struct tcf_ematch_tree t;
136
137	err = tcf_exts_init(&e, TCA_BASIC_ACT, TCA_BASIC_POLICE);
138	if (err < 0)
139		return err;
140	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
141	if (err < 0)
142		goto errout;
143
144	err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &t);
145	if (err < 0)
146		goto errout;
147
148	if (tb[TCA_BASIC_CLASSID]) {
149		f->res.classid = nla_get_u32(tb[TCA_BASIC_CLASSID]);
150		tcf_bind_filter(tp, &f->res, base);
151	}
152
153	tcf_exts_change(tp, &f->exts, &e);
154	tcf_em_tree_change(tp, &f->ematches, &t);
155	f->tp = tp;
156
157	return 0;
158errout:
159	tcf_exts_destroy(&e);
160	return err;
161}
162
163static int basic_change(struct net *net, struct sk_buff *in_skb,
164			struct tcf_proto *tp, unsigned long base, u32 handle,
165			struct nlattr **tca, unsigned long *arg, bool ovr)
166{
167	int err;
168	struct basic_head *head = rtnl_dereference(tp->root);
169	struct nlattr *tb[TCA_BASIC_MAX + 1];
170	struct basic_filter *fold = (struct basic_filter *) *arg;
171	struct basic_filter *fnew;
172
173	if (tca[TCA_OPTIONS] == NULL)
174		return -EINVAL;
175
176	err = nla_parse_nested(tb, TCA_BASIC_MAX, tca[TCA_OPTIONS],
177			       basic_policy);
178	if (err < 0)
179		return err;
180
181	if (fold != NULL) {
182		if (handle && fold->handle != handle)
183			return -EINVAL;
 
184	}
185
186	fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
187	if (!fnew)
188		return -ENOBUFS;
189
190	err = tcf_exts_init(&fnew->exts, TCA_BASIC_ACT, TCA_BASIC_POLICE);
191	if (err < 0)
192		goto errout;
193
194	err = -EINVAL;
195	if (handle) {
196		fnew->handle = handle;
197	} else if (fold) {
198		fnew->handle = fold->handle;
199	} else {
200		unsigned int i = 0x80000000;
201		do {
202			if (++head->hgenerator == 0x7FFFFFFF)
203				head->hgenerator = 1;
204		} while (--i > 0 && basic_get(tp, head->hgenerator));
205
206		if (i <= 0) {
207			pr_err("Insufficient number of handles\n");
208			goto errout;
209		}
210
211		fnew->handle = head->hgenerator;
212	}
213
214	err = basic_set_parms(net, tp, fnew, base, tb, tca[TCA_RATE], ovr);
215	if (err < 0)
216		goto errout;
217
218	*arg = (unsigned long)fnew;
219
220	if (fold) {
221		list_replace_rcu(&fold->link, &fnew->link);
222		tcf_unbind_filter(tp, &fold->res);
223		call_rcu(&fold->rcu, basic_delete_filter);
224	} else {
225		list_add_rcu(&fnew->link, &head->flist);
226	}
227
228	return 0;
229errout:
230	tcf_exts_destroy(&fnew->exts);
231	kfree(fnew);
 
232	return err;
233}
234
235static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg)
236{
237	struct basic_head *head = rtnl_dereference(tp->root);
238	struct basic_filter *f;
239
240	list_for_each_entry(f, &head->flist, link) {
241		if (arg->count < arg->skip)
242			goto skip;
243
244		if (arg->fn(tp, (unsigned long) f, arg) < 0) {
245			arg->stop = 1;
246			break;
247		}
248skip:
249		arg->count++;
250	}
251}
252
253static int basic_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
254		      struct sk_buff *skb, struct tcmsg *t)
255{
256	struct basic_filter *f = (struct basic_filter *) fh;
257	struct nlattr *nest;
258
259	if (f == NULL)
260		return skb->len;
261
262	t->tcm_handle = f->handle;
263
264	nest = nla_nest_start(skb, TCA_OPTIONS);
265	if (nest == NULL)
266		goto nla_put_failure;
267
268	if (f->res.classid &&
269	    nla_put_u32(skb, TCA_BASIC_CLASSID, f->res.classid))
270		goto nla_put_failure;
271
272	if (tcf_exts_dump(skb, &f->exts) < 0 ||
273	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
274		goto nla_put_failure;
275
276	nla_nest_end(skb, nest);
277
278	if (tcf_exts_dump_stats(skb, &f->exts) < 0)
279		goto nla_put_failure;
280
281	return skb->len;
282
283nla_put_failure:
284	nla_nest_cancel(skb, nest);
285	return -1;
286}
287
288static struct tcf_proto_ops cls_basic_ops __read_mostly = {
289	.kind		=	"basic",
290	.classify	=	basic_classify,
291	.init		=	basic_init,
292	.destroy	=	basic_destroy,
293	.get		=	basic_get,
 
294	.change		=	basic_change,
295	.delete		=	basic_delete,
296	.walk		=	basic_walk,
297	.dump		=	basic_dump,
298	.owner		=	THIS_MODULE,
299};
300
301static int __init init_basic(void)
302{
303	return register_tcf_proto_ops(&cls_basic_ops);
304}
305
306static void __exit exit_basic(void)
307{
308	unregister_tcf_proto_ops(&cls_basic_ops);
309}
310
311module_init(init_basic)
312module_exit(exit_basic)
313MODULE_LICENSE("GPL");
314