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
|
/*
* Xtables module to match the process control group.
*
* Might be used to implement individual "per-application" firewall
* policies in contrast to global policies based on control groups.
* Matching is based upon processes tagged to net_cls' classid marker.
*
* (C) 2013 Daniel Borkmann <dborkman@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/skbuff.h>
#include <linux/module.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_cgroup.h>
#include <net/sock.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Daniel Borkmann <dborkman@redhat.com>");
MODULE_DESCRIPTION("Xtables: process control group matching");
MODULE_ALIAS("ipt_cgroup");
MODULE_ALIAS("ip6t_cgroup");
static int cgroup_mt_check_v0(const struct xt_mtchk_param *par)
{
struct xt_cgroup_info_v0 *info = par->matchinfo;
if (info->invert & ~1)
return -EINVAL;
return 0;
}
static int cgroup_mt_check_v1(const struct xt_mtchk_param *par)
{
struct xt_cgroup_info_v1 *info = par->matchinfo;
struct cgroup *cgrp;
if ((info->invert_path & ~1) || (info->invert_classid & ~1))
return -EINVAL;
if (!info->has_path && !info->has_classid) {
pr_info("xt_cgroup: no path or classid specified\n");
return -EINVAL;
}
if (info->has_path && info->has_classid) {
pr_info("xt_cgroup: both path and classid specified\n");
return -EINVAL;
}
info->priv = NULL;
if (info->has_path) {
cgrp = cgroup_get_from_path(info->path);
if (IS_ERR(cgrp)) {
pr_info("xt_cgroup: invalid path, errno=%ld\n",
PTR_ERR(cgrp));
return -EINVAL;
}
info->priv = cgrp;
}
return 0;
}
static bool
cgroup_mt_v0(const struct sk_buff *skb, struct xt_action_param *par)
{
const struct xt_cgroup_info_v0 *info = par->matchinfo;
if (skb->sk == NULL || !sk_fullsock(skb->sk))
return false;
return (info->id == sock_cgroup_classid(&skb->sk->sk_cgrp_data)) ^
info->invert;
}
static bool cgroup_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
{
const struct xt_cgroup_info_v1 *info = par->matchinfo;
struct sock_cgroup_data *skcd = &skb->sk->sk_cgrp_data;
struct cgroup *ancestor = info->priv;
if (!skb->sk || !sk_fullsock(skb->sk))
return false;
if (ancestor)
return cgroup_is_descendant(sock_cgroup_ptr(skcd), ancestor) ^
info->invert_path;
else
return (info->classid == sock_cgroup_classid(skcd)) ^
info->invert_classid;
}
static void cgroup_mt_destroy_v1(const struct xt_mtdtor_param *par)
{
struct xt_cgroup_info_v1 *info = par->matchinfo;
if (info->priv)
cgroup_put(info->priv);
}
static struct xt_match cgroup_mt_reg[] __read_mostly = {
{
.name = "cgroup",
.revision = 0,
.family = NFPROTO_UNSPEC,
.checkentry = cgroup_mt_check_v0,
.match = cgroup_mt_v0,
.matchsize = sizeof(struct xt_cgroup_info_v0),
.me = THIS_MODULE,
.hooks = (1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_POST_ROUTING) |
(1 << NF_INET_LOCAL_IN),
},
{
.name = "cgroup",
.revision = 1,
.family = NFPROTO_UNSPEC,
.checkentry = cgroup_mt_check_v1,
.match = cgroup_mt_v1,
.matchsize = sizeof(struct xt_cgroup_info_v1),
.usersize = offsetof(struct xt_cgroup_info_v1, priv),
.destroy = cgroup_mt_destroy_v1,
.me = THIS_MODULE,
.hooks = (1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_POST_ROUTING) |
(1 << NF_INET_LOCAL_IN),
},
};
static int __init cgroup_mt_init(void)
{
return xt_register_matches(cgroup_mt_reg, ARRAY_SIZE(cgroup_mt_reg));
}
static void __exit cgroup_mt_exit(void)
{
xt_unregister_matches(cgroup_mt_reg, ARRAY_SIZE(cgroup_mt_reg));
}
module_init(cgroup_mt_init);
module_exit(cgroup_mt_exit);
|
