summaryrefslogtreecommitdiff
path: root/security/selinux/netlink.c
blob: 14d810ead42078482807666a41902e4cb24161c0 (plain)
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
/*
 * Netlink event notifications for SELinux.
 *
 * Author: James Morris <jmorris@redhat.com>
 *
 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@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/init.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/selinux_netlink.h>
#include <net/net_namespace.h>
#include <net/netlink.h>

#include "security.h"

static struct sock *selnl;

static int selnl_msglen(int msgtype)
{
	int ret = 0;

	switch (msgtype) {
	case SELNL_MSG_SETENFORCE:
		ret = sizeof(struct selnl_msg_setenforce);
		break;

	case SELNL_MSG_POLICYLOAD:
		ret = sizeof(struct selnl_msg_policyload);
		break;

	default:
		BUG();
	}
	return ret;
}

static void selnl_add_payload(struct nlmsghdr *nlh, int len, int msgtype, void *data)
{
	switch (msgtype) {
	case SELNL_MSG_SETENFORCE: {
		struct selnl_msg_setenforce *msg = nlmsg_data(nlh);

		memset(msg, 0, len);
		msg->val = *((int *)data);
		break;
	}

	case SELNL_MSG_POLICYLOAD: {
		struct selnl_msg_policyload *msg = nlmsg_data(nlh);

		memset(msg, 0, len);
		msg->seqno = *((u32 *)data);
		break;
	}

	default:
		BUG();
	}
}

static void selnl_notify(int msgtype, void *data)
{
	int len;
	sk_buff_data_t tmp;
	struct sk_buff *skb;
	struct nlmsghdr *nlh;

	len = selnl_msglen(msgtype);

	skb = alloc_skb(NLMSG_SPACE(len), GFP_USER);
	if (!skb)
		goto oom;

	tmp = skb->tail;
	nlh = nlmsg_put(skb, 0, 0, msgtype, len, 0);
	if (!nlh)
		goto out_kfree_skb;
	selnl_add_payload(nlh, len, msgtype, data);
	nlh->nlmsg_len = skb->tail - tmp;
	NETLINK_CB(skb).dst_group = SELNLGRP_AVC;
	netlink_broadcast(selnl, skb, 0, SELNLGRP_AVC, GFP_USER);
out:
	return;

out_kfree_skb:
	kfree_skb(skb);
oom:
	printk(KERN_ERR "SELinux:  OOM in %s\n", __func__);
	goto out;
}

void selnl_notify_setenforce(int val)
{
	selnl_notify(SELNL_MSG_SETENFORCE, &val);
}

void selnl_notify_policyload(u32 seqno)
{
	selnl_notify(SELNL_MSG_POLICYLOAD, &seqno);
}

static int __init selnl_init(void)
{
	struct netlink_kernel_cfg cfg = {
		.groups	= SELNLGRP_MAX,
		.flags	= NL_CFG_F_NONROOT_RECV,
	};

	selnl = netlink_kernel_create(&init_net, NETLINK_SELINUX, &cfg);
	if (selnl == NULL)
		panic("SELinux:  Cannot create netlink socket.");
	return 0;
}

__initcall(selnl_init);