selinux: Deprecate and schedule the removal of the the compat_net functionality

This patch is the first step towards removing the old "compat_net" code from
the kernel.  Secmark, the "compat_net" replacement was first introduced in
2.6.18 (September 2006) and the major Linux distributions with SELinux support
have transitioned to Secmark so it is time to start deprecating the "compat_net"
mechanism.  Testing a patched version of 2.6.28-rc6 with the initial release of
Fedora Core 5 did not show any problems when running in enforcing mode.

This patch adds an entry to the feature-removal-schedule.txt file and removes
the SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT configuration option, forcing
Secmark on by default although it can still be disabled at runtime.  The patch
also makes the Secmark permission checks "dynamic" in the sense that they are
only executed when Secmark is configured; this should help prevent problems
with older distributions that have not yet migrated to Secmark.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
This commit is contained in:
Paul Moore 2008-12-31 12:54:11 -05:00
parent 6c2e8ac095
commit 277d342fc4
4 changed files with 23 additions and 38 deletions

View File

@ -324,3 +324,15 @@ When: 2.6.29 (ideally) or 2.6.30 (more likely)
Why: Deprecated by the new (standard) device driver binding model. Use
i2c_driver->probe() and ->remove() instead.
Who: Jean Delvare <khali@linux-fr.org>
---------------------------
What: SELinux "compat_net" functionality
When: 2.6.30 at the earliest
Why: In 2.6.18 the Secmark concept was introduced to replace the "compat_net"
network access control functionality of SELinux. Secmark offers both
better performance and greater flexibility than the "compat_net"
mechanism. Now that the major Linux distributions have moved to
Secmark, it is time to deprecate the older mechanism and start the
process of removing the old code.
Who: Paul Moore <paul.moore@hp.com>

View File

@ -94,33 +94,6 @@ config SECURITY_SELINUX_CHECKREQPROT_VALUE
If you are unsure how to answer this question, answer 1.
config SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
bool "NSA SELinux enable new secmark network controls by default"
depends on SECURITY_SELINUX
default n
help
This option determines whether the new secmark-based network
controls will be enabled by default. If not, the old internal
per-packet controls will be enabled by default, preserving
old behavior.
If you enable the new controls, you will need updated
SELinux userspace libraries, tools and policy. Typically,
your distribution will provide these and enable the new controls
in the kernel they also distribute.
Note that this option can be overridden at boot with the
selinux_compat_net parameter, and after boot via
/selinux/compat_net. See Documentation/kernel-parameters.txt
for details on this parameter.
If you enable the new network controls, you will likely
also require the SECMARK and CONNSECMARK targets, as
well as any conntrack helpers for protocols which you
wish to control.
If you are unsure what to do here, select N.
config SECURITY_SELINUX_POLICYDB_VERSION_MAX
bool "NSA SELinux maximum supported policy format version"
depends on SECURITY_SELINUX

View File

@ -4185,7 +4185,7 @@ static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
u16 family)
{
int err;
int err = 0;
struct sk_security_struct *sksec = sk->sk_security;
u32 peer_sid;
u32 sk_sid = sksec->sid;
@ -4202,7 +4202,7 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
if (selinux_compat_net)
err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
family, addrp);
else
else if (selinux_secmark_enabled())
err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
PACKET__RECV, &ad);
if (err)
@ -4705,7 +4705,7 @@ static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
&ad, family, addrp))
return NF_DROP;
} else {
} else if (selinux_secmark_enabled()) {
if (avc_has_perm(sksec->sid, skb->secmark,
SECCLASS_PACKET, PACKET__SEND, &ad))
return NF_DROP;

View File

@ -47,13 +47,7 @@ static char *policycap_names[] = {
unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
#ifdef CONFIG_SECURITY_SELINUX_ENABLE_SECMARK_DEFAULT
#define SELINUX_COMPAT_NET_VALUE 0
#else
#define SELINUX_COMPAT_NET_VALUE 1
#endif
int selinux_compat_net = SELINUX_COMPAT_NET_VALUE;
int selinux_compat_net = 0;
static int __init checkreqprot_setup(char *str)
{
@ -494,7 +488,13 @@ static ssize_t sel_write_compat_net(struct file *file, const char __user *buf,
if (sscanf(page, "%d", &new_value) != 1)
goto out;
selinux_compat_net = new_value ? 1 : 0;
if (new_value) {
printk(KERN_NOTICE
"SELinux: compat_net is deprecated, please use secmark"
" instead\n");
selinux_compat_net = 1;
} else
selinux_compat_net = 0;
length = count;
out:
free_page((unsigned long) page);