1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/cls_basic.c Basic Packet Classifier.
4 *
5 * Authors: Thomas Graf <tgraf@suug.ch>
6 */
7
8#include <linux/module.h>
9#include <linux/slab.h>
10#include <linux/types.h>
11#include <linux/kernel.h>
12#include <linux/string.h>
13#include <linux/errno.h>
14#include <linux/rtnetlink.h>
15#include <linux/skbuff.h>
16#include <linux/idr.h>
17#include <linux/percpu.h>
18#include <net/netlink.h>
19#include <net/act_api.h>
20#include <net/pkt_cls.h>
21#include <net/tc_wrapper.h>
22
23struct basic_head {
24 struct list_head flist;
25 struct idr handle_idr;
26 struct rcu_head rcu;
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 tcf_proto *tp;
35 struct list_head link;
36 struct tc_basic_pcnt __percpu *pf;
37 struct rcu_work rwork;
38};
39
40TC_INDIRECT_SCOPE int basic_classify(struct sk_buff *skb,
41 const struct tcf_proto *tp,
42 struct tcf_result *res)
43{
44 int r;
45 struct basic_head *head = rcu_dereference_bh(tp->root);
46 struct basic_filter *f;
47
48 list_for_each_entry_rcu(f, &head->flist, link) {
49 __this_cpu_inc(f->pf->rcnt);
50 if (!tcf_em_tree_match(skb, tree: &f->ematches, NULL))
51 continue;
52 __this_cpu_inc(f->pf->rhit);
53 *res = f->res;
54 r = tcf_exts_exec(skb, exts: &f->exts, res);
55 if (r < 0)
56 continue;
57 return r;
58 }
59 return -1;
60}
61
62static void *basic_get(struct tcf_proto *tp, u32 handle)
63{
64 struct basic_head *head = rtnl_dereference(tp->root);
65 struct basic_filter *f;
66
67 list_for_each_entry(f, &head->flist, link) {
68 if (f->handle == handle) {
69 return f;
70 }
71 }
72
73 return NULL;
74}
75
76static int basic_init(struct tcf_proto *tp)
77{
78 struct basic_head *head;
79
80 head = kzalloc(sizeof(*head), GFP_KERNEL);
81 if (head == NULL)
82 return -ENOBUFS;
83 INIT_LIST_HEAD(list: &head->flist);
84 idr_init(idr: &head->handle_idr);
85 rcu_assign_pointer(tp->root, head);
86 return 0;
87}
88
89static void __basic_delete_filter(struct basic_filter *f)
90{
91 tcf_exts_destroy(exts: &f->exts);
92 tcf_em_tree_destroy(&f->ematches);
93 tcf_exts_put_net(exts: &f->exts);
94 free_percpu(pdata: f->pf);
95 kfree(objp: f);
96}
97
98static void basic_delete_filter_work(struct work_struct *work)
99{
100 struct basic_filter *f = container_of(to_rcu_work(work),
101 struct basic_filter,
102 rwork);
103 rtnl_lock();
104 __basic_delete_filter(f);
105 rtnl_unlock();
106}
107
108static void basic_destroy(struct tcf_proto *tp, bool rtnl_held,
109 struct netlink_ext_ack *extack)
110{
111 struct basic_head *head = rtnl_dereference(tp->root);
112 struct basic_filter *f, *n;
113
114 list_for_each_entry_safe(f, n, &head->flist, link) {
115 list_del_rcu(entry: &f->link);
116 tcf_unbind_filter(tp, r: &f->res);
117 idr_remove(&head->handle_idr, id: f->handle);
118 if (tcf_exts_get_net(exts: &f->exts))
119 tcf_queue_work(rwork: &f->rwork, func: basic_delete_filter_work);
120 else
121 __basic_delete_filter(f);
122 }
123 idr_destroy(&head->handle_idr);
124 kfree_rcu(head, rcu);
125}
126
127static int basic_delete(struct tcf_proto *tp, void *arg, bool *last,
128 bool rtnl_held, struct netlink_ext_ack *extack)
129{
130 struct basic_head *head = rtnl_dereference(tp->root);
131 struct basic_filter *f = arg;
132
133 list_del_rcu(entry: &f->link);
134 tcf_unbind_filter(tp, r: &f->res);
135 idr_remove(&head->handle_idr, id: f->handle);
136 tcf_exts_get_net(exts: &f->exts);
137 tcf_queue_work(rwork: &f->rwork, func: basic_delete_filter_work);
138 *last = list_empty(head: &head->flist);
139 return 0;
140}
141
142static const struct nla_policy basic_policy[TCA_BASIC_MAX + 1] = {
143 [TCA_BASIC_CLASSID] = { .type = NLA_U32 },
144 [TCA_BASIC_EMATCHES] = { .type = NLA_NESTED },
145};
146
147static int basic_set_parms(struct net *net, struct tcf_proto *tp,
148 struct basic_filter *f, unsigned long base,
149 struct nlattr **tb,
150 struct nlattr *est, u32 flags,
151 struct netlink_ext_ack *extack)
152{
153 int err;
154
155 err = tcf_exts_validate(net, tp, tb, rate_tlv: est, exts: &f->exts, flags, extack);
156 if (err < 0)
157 return err;
158
159 err = tcf_em_tree_validate(tp, tb[TCA_BASIC_EMATCHES], &f->ematches);
160 if (err < 0)
161 return err;
162
163 if (tb[TCA_BASIC_CLASSID]) {
164 f->res.classid = nla_get_u32(nla: tb[TCA_BASIC_CLASSID]);
165 tcf_bind_filter(tp, r: &f->res, base);
166 }
167
168 f->tp = tp;
169 return 0;
170}
171
172static int basic_change(struct net *net, struct sk_buff *in_skb,
173 struct tcf_proto *tp, unsigned long base, u32 handle,
174 struct nlattr **tca, void **arg,
175 u32 flags, struct netlink_ext_ack *extack)
176{
177 int err;
178 struct basic_head *head = rtnl_dereference(tp->root);
179 struct nlattr *tb[TCA_BASIC_MAX + 1];
180 struct basic_filter *fold = (struct basic_filter *) *arg;
181 struct basic_filter *fnew;
182
183 if (tca[TCA_OPTIONS] == NULL)
184 return -EINVAL;
185
186 err = nla_parse_nested_deprecated(tb, TCA_BASIC_MAX, nla: tca[TCA_OPTIONS],
187 policy: basic_policy, NULL);
188 if (err < 0)
189 return err;
190
191 if (fold != NULL) {
192 if (handle && fold->handle != handle)
193 return -EINVAL;
194 }
195
196 fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
197 if (!fnew)
198 return -ENOBUFS;
199
200 err = tcf_exts_init(exts: &fnew->exts, net, action: TCA_BASIC_ACT, police: TCA_BASIC_POLICE);
201 if (err < 0)
202 goto errout;
203
204 if (!handle) {
205 handle = 1;
206 err = idr_alloc_u32(&head->handle_idr, ptr: fnew, id: &handle,
207 INT_MAX, GFP_KERNEL);
208 } else if (!fold) {
209 err = idr_alloc_u32(&head->handle_idr, ptr: fnew, id: &handle,
210 max: handle, GFP_KERNEL);
211 }
212 if (err)
213 goto errout;
214 fnew->handle = handle;
215 fnew->pf = alloc_percpu(struct tc_basic_pcnt);
216 if (!fnew->pf) {
217 err = -ENOMEM;
218 goto errout;
219 }
220
221 err = basic_set_parms(net, tp, f: fnew, base, tb, est: tca[TCA_RATE], flags,
222 extack);
223 if (err < 0) {
224 if (!fold)
225 idr_remove(&head->handle_idr, id: fnew->handle);
226 goto errout;
227 }
228
229 *arg = fnew;
230
231 if (fold) {
232 idr_replace(&head->handle_idr, fnew, id: fnew->handle);
233 list_replace_rcu(old: &fold->link, new: &fnew->link);
234 tcf_unbind_filter(tp, r: &fold->res);
235 tcf_exts_get_net(exts: &fold->exts);
236 tcf_queue_work(rwork: &fold->rwork, func: basic_delete_filter_work);
237 } else {
238 list_add_rcu(new: &fnew->link, head: &head->flist);
239 }
240
241 return 0;
242errout:
243 free_percpu(pdata: fnew->pf);
244 tcf_exts_destroy(exts: &fnew->exts);
245 kfree(objp: fnew);
246 return err;
247}
248
249static void basic_walk(struct tcf_proto *tp, struct tcf_walker *arg,
250 bool rtnl_held)
251{
252 struct basic_head *head = rtnl_dereference(tp->root);
253 struct basic_filter *f;
254
255 list_for_each_entry(f, &head->flist, link) {
256 if (!tc_cls_stats_dump(tp, arg, filter: f))
257 break;
258 }
259}
260
261static void basic_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
262 unsigned long base)
263{
264 struct basic_filter *f = fh;
265
266 tc_cls_bind_class(classid, cl, q, res: &f->res, base);
267}
268
269static int basic_dump(struct net *net, struct tcf_proto *tp, void *fh,
270 struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
271{
272 struct tc_basic_pcnt gpf = {};
273 struct basic_filter *f = fh;
274 struct nlattr *nest;
275 int cpu;
276
277 if (f == NULL)
278 return skb->len;
279
280 t->tcm_handle = f->handle;
281
282 nest = nla_nest_start_noflag(skb, attrtype: TCA_OPTIONS);
283 if (nest == NULL)
284 goto nla_put_failure;
285
286 if (f->res.classid &&
287 nla_put_u32(skb, attrtype: TCA_BASIC_CLASSID, value: f->res.classid))
288 goto nla_put_failure;
289
290 for_each_possible_cpu(cpu) {
291 struct tc_basic_pcnt *pf = per_cpu_ptr(f->pf, cpu);
292
293 gpf.rcnt += pf->rcnt;
294 gpf.rhit += pf->rhit;
295 }
296
297 if (nla_put_64bit(skb, attrtype: TCA_BASIC_PCNT,
298 attrlen: sizeof(struct tc_basic_pcnt),
299 data: &gpf, padattr: TCA_BASIC_PAD))
300 goto nla_put_failure;
301
302 if (tcf_exts_dump(skb, exts: &f->exts) < 0 ||
303 tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
304 goto nla_put_failure;
305
306 nla_nest_end(skb, start: nest);
307
308 if (tcf_exts_dump_stats(skb, exts: &f->exts) < 0)
309 goto nla_put_failure;
310
311 return skb->len;
312
313nla_put_failure:
314 nla_nest_cancel(skb, start: nest);
315 return -1;
316}
317
318static struct tcf_proto_ops cls_basic_ops __read_mostly = {
319 .kind = "basic",
320 .classify = basic_classify,
321 .init = basic_init,
322 .destroy = basic_destroy,
323 .get = basic_get,
324 .change = basic_change,
325 .delete = basic_delete,
326 .walk = basic_walk,
327 .dump = basic_dump,
328 .bind_class = basic_bind_class,
329 .owner = THIS_MODULE,
330};
331MODULE_ALIAS_NET_CLS("basic");
332
333static int __init init_basic(void)
334{
335 return register_tcf_proto_ops(ops: &cls_basic_ops);
336}
337
338static void __exit exit_basic(void)
339{
340 unregister_tcf_proto_ops(ops: &cls_basic_ops);
341}
342
343module_init(init_basic)
344module_exit(exit_basic)
345MODULE_DESCRIPTION("TC basic classifier");
346MODULE_LICENSE("GPL");
347

source code of linux/net/sched/cls_basic.c