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12#include <linux/init.h>
13#include <linux/types.h>
14#include <linux/slab.h>
15#include <linux/stddef.h>
16#include <linux/kernel.h>
17#include <linux/export.h>
18#include <linux/skbuff.h>
19#include <linux/netlink.h>
20#include <linux/selinux_netlink.h>
21#include <net/net_namespace.h>
22#include <net/netlink.h>
23
24#include "security.h"
25
26static struct sock *selnl;
27
28static int selnl_msglen(int msgtype)
29{
30 int ret = 0;
31
32 switch (msgtype) {
33 case SELNL_MSG_SETENFORCE:
34 ret = sizeof(struct selnl_msg_setenforce);
35 break;
36
37 case SELNL_MSG_POLICYLOAD:
38 ret = sizeof(struct selnl_msg_policyload);
39 break;
40
41 default:
42 BUG();
43 }
44 return ret;
45}
46
47static void selnl_add_payload(struct nlmsghdr *nlh, int len, int msgtype, void *data)
48{
49 switch (msgtype) {
50 case SELNL_MSG_SETENFORCE: {
51 struct selnl_msg_setenforce *msg = nlmsg_data(nlh);
52
53 memset(msg, 0, len);
54 msg->val = *((int *)data);
55 break;
56 }
57
58 case SELNL_MSG_POLICYLOAD: {
59 struct selnl_msg_policyload *msg = nlmsg_data(nlh);
60
61 memset(msg, 0, len);
62 msg->seqno = *((u32 *)data);
63 break;
64 }
65
66 default:
67 BUG();
68 }
69}
70
71static void selnl_notify(int msgtype, void *data)
72{
73 int len;
74 sk_buff_data_t tmp;
75 struct sk_buff *skb;
76 struct nlmsghdr *nlh;
77
78 len = selnl_msglen(msgtype);
79
80 skb = alloc_skb(NLMSG_SPACE(len), GFP_USER);
81 if (!skb)
82 goto oom;
83
84 tmp = skb->tail;
85 nlh = nlmsg_put(skb, 0, 0, msgtype, len, 0);
86 if (!nlh)
87 goto out_kfree_skb;
88 selnl_add_payload(nlh, len, msgtype, data);
89 nlh->nlmsg_len = skb->tail - tmp;
90 NETLINK_CB(skb).dst_group = SELNLGRP_AVC;
91 netlink_broadcast(selnl, skb, 0, SELNLGRP_AVC, GFP_USER);
92out:
93 return;
94
95out_kfree_skb:
96 kfree_skb(skb);
97oom:
98 printk(KERN_ERR "SELinux: OOM in %s\n", __func__);
99 goto out;
100}
101
102void selnl_notify_setenforce(int val)
103{
104 selnl_notify(SELNL_MSG_SETENFORCE, &val);
105}
106
107void selnl_notify_policyload(u32 seqno)
108{
109 selnl_notify(SELNL_MSG_POLICYLOAD, &seqno);
110}
111
112static int __init selnl_init(void)
113{
114 struct netlink_kernel_cfg cfg = {
115 .groups = SELNLGRP_MAX,
116 .flags = NL_CFG_F_NONROOT_RECV,
117 };
118
119 selnl = netlink_kernel_create(&init_net, NETLINK_SELINUX, &cfg);
120 if (selnl == NULL)
121 panic("SELinux: Cannot create netlink socket.");
122 return 0;
123}
124
125__initcall(selnl_init);
126