1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * cls_cgroup.h			Control Group Classifier
 4 *
 5 * Authors:	Thomas Graf <tgraf@suug.ch>
 
 
 
 
 
 
 6 */
 7
 8#ifndef _NET_CLS_CGROUP_H
 9#define _NET_CLS_CGROUP_H
10
11#include <linux/cgroup.h>
12#include <linux/hardirq.h>
13#include <linux/rcupdate.h>
14#include <net/sock.h>
15#include <net/inet_sock.h>
16
17#ifdef CONFIG_CGROUP_NET_CLASSID
18struct cgroup_cls_state {
19	struct cgroup_subsys_state css;
20	u32 classid;
21};
22
23struct cgroup_cls_state *task_cls_state(struct task_struct *p);
24
25static inline u32 task_cls_classid(struct task_struct *p)
26{
27	u32 classid;
28
29	if (in_interrupt())
30		return 0;
31
32	rcu_read_lock();
33	classid = container_of(task_css(p, net_cls_cgrp_id),
34			       struct cgroup_cls_state, css)->classid;
35	rcu_read_unlock();
36
37	return classid;
38}
39
40static inline void sock_update_classid(struct sock_cgroup_data *skcd)
41{
42	u32 classid;
43
44	classid = task_cls_classid(current);
45	sock_cgroup_set_classid(skcd, classid);
46}
47
48static inline u32 task_get_classid(const struct sk_buff *skb)
49{
50	u32 classid = task_cls_state(current)->classid;
51
52	/* Due to the nature of the classifier it is required to ignore all
53	 * packets originating from softirq context as accessing `current'
54	 * would lead to false results.
55	 *
56	 * This test assumes that all callers of dev_queue_xmit() explicitly
57	 * disable bh. Knowing this, it is possible to detect softirq based
58	 * calls by looking at the number of nested bh disable calls because
59	 * softirqs always disables bh.
60	 */
61	if (in_serving_softirq()) {
62		struct sock *sk = skb_to_full_sk(skb);
63
64		/* If there is an sock_cgroup_classid we'll use that. */
65		if (!sk || !sk_fullsock(sk))
66			return 0;
67
68		classid = sock_cgroup_classid(&sk->sk_cgrp_data);
69	}
70
71	return classid;
72}
73#else /* !CONFIG_CGROUP_NET_CLASSID */
74static inline void sock_update_classid(struct sock_cgroup_data *skcd)
75{
76}
77
78static inline u32 task_get_classid(const struct sk_buff *skb)
79{
80	return 0;
81}
82#endif /* CONFIG_CGROUP_NET_CLASSID */
83#endif  /* _NET_CLS_CGROUP_H */

 
 1/*
 2 * cls_cgroup.h			Control Group Classifier
 3 *
 4 * Authors:	Thomas Graf <tgraf@suug.ch>
 5 *
 6 * This program is free software; you can redistribute it and/or modify it
 7 * under the terms of the GNU General Public License as published by the Free
 8 * Software Foundation; either version 2 of the License, or (at your option)
 9 * any later version.
10 *
11 */
12
13#ifndef _NET_CLS_CGROUP_H
14#define _NET_CLS_CGROUP_H
15
16#include <linux/cgroup.h>
17#include <linux/hardirq.h>
18#include <linux/rcupdate.h>
19#include <net/sock.h>
 
20
21#ifdef CONFIG_CGROUP_NET_CLASSID
22struct cgroup_cls_state {
23	struct cgroup_subsys_state css;
24	u32 classid;
25};
26
27struct cgroup_cls_state *task_cls_state(struct task_struct *p);
28
29static inline u32 task_cls_classid(struct task_struct *p)
30{
31	u32 classid;
32
33	if (in_interrupt())
34		return 0;
35
36	rcu_read_lock();
37	classid = container_of(task_css(p, net_cls_cgrp_id),
38			       struct cgroup_cls_state, css)->classid;
39	rcu_read_unlock();
40
41	return classid;
42}
43
44static inline void sock_update_classid(struct sock *sk)
45{
46	u32 classid;
47
48	classid = task_cls_classid(current);
49	if (classid != sk->sk_classid)
50		sk->sk_classid = classid;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
51}
52#else /* !CONFIG_CGROUP_NET_CLASSID */
53static inline void sock_update_classid(struct sock *sk)
 
 
 
 
54{
 
55}
56#endif /* CONFIG_CGROUP_NET_CLASSID */
57#endif  /* _NET_CLS_CGROUP_H */