linux/security/selinux/netlink.c
Eric W. Biederman b4b510290b [NET]: Support multiple network namespaces with netlink
Each netlink socket will live in exactly one network namespace,
this includes the controlling kernel sockets.

This patch updates all of the existing netlink protocols
to only support the initial network namespace.  Request
by clients in other namespaces will get -ECONREFUSED.
As they would if the kernel did not have the support for
that netlink protocol compiled in.

As each netlink protocol is updated to be multiple network
namespace safe it can register multiple kernel sockets
to acquire a presence in the rest of the network namespaces.

The implementation in af_netlink is a simple filter implementation
at hash table insertion and hash table look up time.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:49:09 -07:00

117 lines
2.4 KiB
C

/*
* 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/stddef.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/selinux_netlink.h>
#include <net/net_namespace.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);
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;
nlmsg_failure:
kfree_skb(skb);
oom:
printk(KERN_ERR "SELinux: OOM in %s\n", __FUNCTION__);
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)
{
selnl = netlink_kernel_create(&init_net, NETLINK_SELINUX,
SELNLGRP_MAX, NULL, NULL, THIS_MODULE);
if (selnl == NULL)
panic("SELinux: Cannot create netlink socket.");
netlink_set_nonroot(NETLINK_SELINUX, NL_NONROOT_RECV);
return 0;
}
__initcall(selnl_init);