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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/sched/cls_cgroup.c Control Group Classifier
4 *
5 * Authors: Thomas Graf <tgraf@suug.ch>
6 */
7
8#include <linux/module.h>
9#include <linux/slab.h>
10#include <linux/skbuff.h>
11#include <linux/rcupdate.h>
12#include <net/rtnetlink.h>
13#include <net/pkt_cls.h>
14#include <net/sock.h>
15#include <net/cls_cgroup.h>
16#include <net/tc_wrapper.h>
17
18struct cls_cgroup_head {
19 u32 handle;
20 struct tcf_exts exts;
21 struct tcf_ematch_tree ematches;
22 struct tcf_proto *tp;
23 struct rcu_work rwork;
24};
25
26TC_INDIRECT_SCOPE int cls_cgroup_classify(struct sk_buff *skb,
27 const struct tcf_proto *tp,
28 struct tcf_result *res)
29{
30 struct cls_cgroup_head *head = rcu_dereference_bh(tp->root);
31 u32 classid = task_get_classid(skb);
32
33 if (unlikely(!head))
34 return -1;
35 if (!classid)
36 return -1;
37 if (!tcf_em_tree_match(skb, &head->ematches, NULL))
38 return -1;
39
40 res->classid = classid;
41 res->class = 0;
42
43 return tcf_exts_exec(skb, &head->exts, res);
44}
45
46static void *cls_cgroup_get(struct tcf_proto *tp, u32 handle)
47{
48 return NULL;
49}
50
51static int cls_cgroup_init(struct tcf_proto *tp)
52{
53 return 0;
54}
55
56static const struct nla_policy cgroup_policy[TCA_CGROUP_MAX + 1] = {
57 [TCA_CGROUP_EMATCHES] = { .type = NLA_NESTED },
58};
59
60static void __cls_cgroup_destroy(struct cls_cgroup_head *head)
61{
62 tcf_exts_destroy(&head->exts);
63 tcf_em_tree_destroy(&head->ematches);
64 tcf_exts_put_net(&head->exts);
65 kfree(head);
66}
67
68static void cls_cgroup_destroy_work(struct work_struct *work)
69{
70 struct cls_cgroup_head *head = container_of(to_rcu_work(work),
71 struct cls_cgroup_head,
72 rwork);
73 rtnl_lock();
74 __cls_cgroup_destroy(head);
75 rtnl_unlock();
76}
77
78static int cls_cgroup_change(struct net *net, struct sk_buff *in_skb,
79 struct tcf_proto *tp, unsigned long base,
80 u32 handle, struct nlattr **tca,
81 void **arg, u32 flags,
82 struct netlink_ext_ack *extack)
83{
84 struct nlattr *tb[TCA_CGROUP_MAX + 1];
85 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
86 struct cls_cgroup_head *new;
87 int err;
88
89 if (!tca[TCA_OPTIONS])
90 return -EINVAL;
91
92 if (!head && !handle)
93 return -EINVAL;
94
95 if (head && handle != head->handle)
96 return -ENOENT;
97
98 new = kzalloc(sizeof(*head), GFP_KERNEL);
99 if (!new)
100 return -ENOBUFS;
101
102 err = tcf_exts_init(&new->exts, net, TCA_CGROUP_ACT, TCA_CGROUP_POLICE);
103 if (err < 0)
104 goto errout;
105 new->handle = handle;
106 new->tp = tp;
107 err = nla_parse_nested_deprecated(tb, TCA_CGROUP_MAX,
108 tca[TCA_OPTIONS], cgroup_policy,
109 NULL);
110 if (err < 0)
111 goto errout;
112
113 err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &new->exts, flags,
114 extack);
115 if (err < 0)
116 goto errout;
117
118 err = tcf_em_tree_validate(tp, tb[TCA_CGROUP_EMATCHES], &new->ematches);
119 if (err < 0)
120 goto errout;
121
122 rcu_assign_pointer(tp->root, new);
123 if (head) {
124 tcf_exts_get_net(&head->exts);
125 tcf_queue_work(&head->rwork, cls_cgroup_destroy_work);
126 }
127 return 0;
128errout:
129 tcf_exts_destroy(&new->exts);
130 kfree(new);
131 return err;
132}
133
134static void cls_cgroup_destroy(struct tcf_proto *tp, bool rtnl_held,
135 struct netlink_ext_ack *extack)
136{
137 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
138
139 /* Head can still be NULL due to cls_cgroup_init(). */
140 if (head) {
141 if (tcf_exts_get_net(&head->exts))
142 tcf_queue_work(&head->rwork, cls_cgroup_destroy_work);
143 else
144 __cls_cgroup_destroy(head);
145 }
146}
147
148static int cls_cgroup_delete(struct tcf_proto *tp, void *arg, bool *last,
149 bool rtnl_held, struct netlink_ext_ack *extack)
150{
151 return -EOPNOTSUPP;
152}
153
154static void cls_cgroup_walk(struct tcf_proto *tp, struct tcf_walker *arg,
155 bool rtnl_held)
156{
157 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
158
159 if (arg->count < arg->skip)
160 goto skip;
161
162 if (!head)
163 return;
164 if (arg->fn(tp, head, arg) < 0) {
165 arg->stop = 1;
166 return;
167 }
168skip:
169 arg->count++;
170}
171
172static int cls_cgroup_dump(struct net *net, struct tcf_proto *tp, void *fh,
173 struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
174{
175 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
176 struct nlattr *nest;
177
178 t->tcm_handle = head->handle;
179
180 nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
181 if (nest == NULL)
182 goto nla_put_failure;
183
184 if (tcf_exts_dump(skb, &head->exts) < 0 ||
185 tcf_em_tree_dump(skb, &head->ematches, TCA_CGROUP_EMATCHES) < 0)
186 goto nla_put_failure;
187
188 nla_nest_end(skb, nest);
189
190 if (tcf_exts_dump_stats(skb, &head->exts) < 0)
191 goto nla_put_failure;
192
193 return skb->len;
194
195nla_put_failure:
196 nla_nest_cancel(skb, nest);
197 return -1;
198}
199
200static struct tcf_proto_ops cls_cgroup_ops __read_mostly = {
201 .kind = "cgroup",
202 .init = cls_cgroup_init,
203 .change = cls_cgroup_change,
204 .classify = cls_cgroup_classify,
205 .destroy = cls_cgroup_destroy,
206 .get = cls_cgroup_get,
207 .delete = cls_cgroup_delete,
208 .walk = cls_cgroup_walk,
209 .dump = cls_cgroup_dump,
210 .owner = THIS_MODULE,
211};
212MODULE_ALIAS_NET_CLS("cgroup");
213
214static int __init init_cgroup_cls(void)
215{
216 return register_tcf_proto_ops(&cls_cgroup_ops);
217}
218
219static void __exit exit_cgroup_cls(void)
220{
221 unregister_tcf_proto_ops(&cls_cgroup_ops);
222}
223
224module_init(init_cgroup_cls);
225module_exit(exit_cgroup_cls);
226MODULE_DESCRIPTION("TC cgroup classifier");
227MODULE_LICENSE("GPL");
1/*
2 * net/sched/cls_cgroup.c Control Group 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/skbuff.h>
15#include <linux/rcupdate.h>
16#include <net/rtnetlink.h>
17#include <net/pkt_cls.h>
18#include <net/sock.h>
19#include <net/cls_cgroup.h>
20
21struct cls_cgroup_head {
22 u32 handle;
23 struct tcf_exts exts;
24 struct tcf_ematch_tree ematches;
25 struct tcf_proto *tp;
26 union {
27 struct work_struct work;
28 struct rcu_head rcu;
29 };
30};
31
32static int cls_cgroup_classify(struct sk_buff *skb, const struct tcf_proto *tp,
33 struct tcf_result *res)
34{
35 struct cls_cgroup_head *head = rcu_dereference_bh(tp->root);
36 u32 classid = task_get_classid(skb);
37
38 if (!classid)
39 return -1;
40 if (!tcf_em_tree_match(skb, &head->ematches, NULL))
41 return -1;
42
43 res->classid = classid;
44 res->class = 0;
45
46 return tcf_exts_exec(skb, &head->exts, res);
47}
48
49static void *cls_cgroup_get(struct tcf_proto *tp, u32 handle)
50{
51 return NULL;
52}
53
54static int cls_cgroup_init(struct tcf_proto *tp)
55{
56 return 0;
57}
58
59static const struct nla_policy cgroup_policy[TCA_CGROUP_MAX + 1] = {
60 [TCA_CGROUP_EMATCHES] = { .type = NLA_NESTED },
61};
62
63static void __cls_cgroup_destroy(struct cls_cgroup_head *head)
64{
65 tcf_exts_destroy(&head->exts);
66 tcf_em_tree_destroy(&head->ematches);
67 tcf_exts_put_net(&head->exts);
68 kfree(head);
69}
70
71static void cls_cgroup_destroy_work(struct work_struct *work)
72{
73 struct cls_cgroup_head *head = container_of(work,
74 struct cls_cgroup_head,
75 work);
76 rtnl_lock();
77 __cls_cgroup_destroy(head);
78 rtnl_unlock();
79}
80
81static void cls_cgroup_destroy_rcu(struct rcu_head *root)
82{
83 struct cls_cgroup_head *head = container_of(root,
84 struct cls_cgroup_head,
85 rcu);
86
87 INIT_WORK(&head->work, cls_cgroup_destroy_work);
88 tcf_queue_work(&head->work);
89}
90
91static int cls_cgroup_change(struct net *net, struct sk_buff *in_skb,
92 struct tcf_proto *tp, unsigned long base,
93 u32 handle, struct nlattr **tca,
94 void **arg, bool ovr,
95 struct netlink_ext_ack *extack)
96{
97 struct nlattr *tb[TCA_CGROUP_MAX + 1];
98 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
99 struct cls_cgroup_head *new;
100 int err;
101
102 if (!tca[TCA_OPTIONS])
103 return -EINVAL;
104
105 if (!head && !handle)
106 return -EINVAL;
107
108 if (head && handle != head->handle)
109 return -ENOENT;
110
111 new = kzalloc(sizeof(*head), GFP_KERNEL);
112 if (!new)
113 return -ENOBUFS;
114
115 err = tcf_exts_init(&new->exts, TCA_CGROUP_ACT, TCA_CGROUP_POLICE);
116 if (err < 0)
117 goto errout;
118 new->handle = handle;
119 new->tp = tp;
120 err = nla_parse_nested(tb, TCA_CGROUP_MAX, tca[TCA_OPTIONS],
121 cgroup_policy, NULL);
122 if (err < 0)
123 goto errout;
124
125 err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &new->exts, ovr,
126 extack);
127 if (err < 0)
128 goto errout;
129
130 err = tcf_em_tree_validate(tp, tb[TCA_CGROUP_EMATCHES], &new->ematches);
131 if (err < 0)
132 goto errout;
133
134 rcu_assign_pointer(tp->root, new);
135 if (head) {
136 tcf_exts_get_net(&head->exts);
137 call_rcu(&head->rcu, cls_cgroup_destroy_rcu);
138 }
139 return 0;
140errout:
141 tcf_exts_destroy(&new->exts);
142 kfree(new);
143 return err;
144}
145
146static void cls_cgroup_destroy(struct tcf_proto *tp,
147 struct netlink_ext_ack *extack)
148{
149 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
150
151 /* Head can still be NULL due to cls_cgroup_init(). */
152 if (head) {
153 if (tcf_exts_get_net(&head->exts))
154 call_rcu(&head->rcu, cls_cgroup_destroy_rcu);
155 else
156 __cls_cgroup_destroy(head);
157 }
158}
159
160static int cls_cgroup_delete(struct tcf_proto *tp, void *arg, bool *last,
161 struct netlink_ext_ack *extack)
162{
163 return -EOPNOTSUPP;
164}
165
166static void cls_cgroup_walk(struct tcf_proto *tp, struct tcf_walker *arg)
167{
168 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
169
170 if (arg->count < arg->skip)
171 goto skip;
172
173 if (arg->fn(tp, head, arg) < 0) {
174 arg->stop = 1;
175 return;
176 }
177skip:
178 arg->count++;
179}
180
181static int cls_cgroup_dump(struct net *net, struct tcf_proto *tp, void *fh,
182 struct sk_buff *skb, struct tcmsg *t)
183{
184 struct cls_cgroup_head *head = rtnl_dereference(tp->root);
185 struct nlattr *nest;
186
187 t->tcm_handle = head->handle;
188
189 nest = nla_nest_start(skb, TCA_OPTIONS);
190 if (nest == NULL)
191 goto nla_put_failure;
192
193 if (tcf_exts_dump(skb, &head->exts) < 0 ||
194 tcf_em_tree_dump(skb, &head->ematches, TCA_CGROUP_EMATCHES) < 0)
195 goto nla_put_failure;
196
197 nla_nest_end(skb, nest);
198
199 if (tcf_exts_dump_stats(skb, &head->exts) < 0)
200 goto nla_put_failure;
201
202 return skb->len;
203
204nla_put_failure:
205 nla_nest_cancel(skb, nest);
206 return -1;
207}
208
209static struct tcf_proto_ops cls_cgroup_ops __read_mostly = {
210 .kind = "cgroup",
211 .init = cls_cgroup_init,
212 .change = cls_cgroup_change,
213 .classify = cls_cgroup_classify,
214 .destroy = cls_cgroup_destroy,
215 .get = cls_cgroup_get,
216 .delete = cls_cgroup_delete,
217 .walk = cls_cgroup_walk,
218 .dump = cls_cgroup_dump,
219 .owner = THIS_MODULE,
220};
221
222static int __init init_cgroup_cls(void)
223{
224 return register_tcf_proto_ops(&cls_cgroup_ops);
225}
226
227static void __exit exit_cgroup_cls(void)
228{
229 unregister_tcf_proto_ops(&cls_cgroup_ops);
230}
231
232module_init(init_cgroup_cls);
233module_exit(exit_cgroup_cls);
234MODULE_LICENSE("GPL");