1 /* 2 * Netlink event notifications for SELinux. 3 * 4 * Author: James Morris <jmorris@redhat.com> 5 * 6 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2, 10 * as published by the Free Software Foundation. 11 */ 12 #include <linux/init.h> 13 #include <linux/types.h> 14 #include <linux/stddef.h> 15 #include <linux/kernel.h> 16 #include <linux/list.h> 17 #include <linux/skbuff.h> 18 #include <linux/netlink.h> 19 #include <linux/selinux_netlink.h> 20 #include <net/net_namespace.h> 21 22 static struct sock *selnl; 23 24 static int selnl_msglen(int msgtype) 25 { 26 int ret = 0; 27 28 switch (msgtype) { 29 case SELNL_MSG_SETENFORCE: 30 ret = sizeof(struct selnl_msg_setenforce); 31 break; 32 33 case SELNL_MSG_POLICYLOAD: 34 ret = sizeof(struct selnl_msg_policyload); 35 break; 36 37 default: 38 BUG(); 39 } 40 return ret; 41 } 42 43 static void selnl_add_payload(struct nlmsghdr *nlh, int len, int msgtype, void *data) 44 { 45 switch (msgtype) { 46 case SELNL_MSG_SETENFORCE: { 47 struct selnl_msg_setenforce *msg = NLMSG_DATA(nlh); 48 49 memset(msg, 0, len); 50 msg->val = *((int *)data); 51 break; 52 } 53 54 case SELNL_MSG_POLICYLOAD: { 55 struct selnl_msg_policyload *msg = NLMSG_DATA(nlh); 56 57 memset(msg, 0, len); 58 msg->seqno = *((u32 *)data); 59 break; 60 } 61 62 default: 63 BUG(); 64 } 65 } 66 67 static void selnl_notify(int msgtype, void *data) 68 { 69 int len; 70 sk_buff_data_t tmp; 71 struct sk_buff *skb; 72 struct nlmsghdr *nlh; 73 74 len = selnl_msglen(msgtype); 75 76 skb = alloc_skb(NLMSG_SPACE(len), GFP_USER); 77 if (!skb) 78 goto oom; 79 80 tmp = skb->tail; 81 nlh = NLMSG_PUT(skb, 0, 0, msgtype, len); 82 selnl_add_payload(nlh, len, msgtype, data); 83 nlh->nlmsg_len = skb->tail - tmp; 84 NETLINK_CB(skb).dst_group = SELNLGRP_AVC; 85 netlink_broadcast(selnl, skb, 0, SELNLGRP_AVC, GFP_USER); 86 out: 87 return; 88 89 nlmsg_failure: 90 kfree_skb(skb); 91 oom: 92 printk(KERN_ERR "SELinux: OOM in %s\n", __FUNCTION__); 93 goto out; 94 } 95 96 void selnl_notify_setenforce(int val) 97 { 98 selnl_notify(SELNL_MSG_SETENFORCE, &val); 99 } 100 101 void selnl_notify_policyload(u32 seqno) 102 { 103 selnl_notify(SELNL_MSG_POLICYLOAD, &seqno); 104 } 105 106 static int __init selnl_init(void) 107 { 108 selnl = netlink_kernel_create(&init_net, NETLINK_SELINUX, 109 SELNLGRP_MAX, NULL, NULL, THIS_MODULE); 110 if (selnl == NULL) 111 panic("SELinux: Cannot create netlink socket."); 112 netlink_set_nonroot(NETLINK_SELINUX, NL_NONROOT_RECV); 113 return 0; 114 } 115 116 __initcall(selnl_init); 117