diff mbox series

[v4] scripts/selinux: modernize mdp

Message ID 20190220194302.2075-1-dominick.grift@defensec.nl (mailing list archive)
State Superseded
Headers show
Series [v4] scripts/selinux: modernize mdp | expand

Commit Message

Dominick Grift Feb. 20, 2019, 7:43 p.m. UTC
The MDP example no longer works on modern systems.

Add support for devtmpfs. This is required by login programs to relabel terminals.
Compile the policy with deny_unknown allow status to anticipate user space object managers in core components such as systemd.
Add default seusers mapping and failsafe context for the SELinux PAM module.

V2:
Fix existing file test for setfiles.
Add a file test for checkpolicy similar to the test for setfiles for consistency.
Execute setfiles with -F to ensure that customizables are relabeled as well in scenarios where filesystems are labeled but where SELinux is disabled.

V3: Fixes file test that was introduced in V2.

V4: Remove file tests and instead rely on which

Signed-off-by: Dominick Grift <dominick.grift@defensec.nl>
---
 scripts/selinux/install_policy.sh | 23 +++++++++++++----------
 scripts/selinux/mdp/mdp.c         |  1 +
 2 files changed, 14 insertions(+), 10 deletions(-)

Comments

Dominick Grift Feb. 20, 2019, 8:32 p.m. UTC | #1
On Wed, Feb 20, 2019 at 08:43:02PM +0100, Dominick Grift wrote:
> The MDP example no longer works on modern systems.

I would prefer that my changes would just be addressed in Stephen's patch instead.
In that case this patch can be ignored.

> 
> Add support for devtmpfs. This is required by login programs to relabel terminals.
> Compile the policy with deny_unknown allow status to anticipate user space object managers in core components such as systemd.
> Add default seusers mapping and failsafe context for the SELinux PAM module.
> 
> V2:
> Fix existing file test for setfiles.
> Add a file test for checkpolicy similar to the test for setfiles for consistency.
> Execute setfiles with -F to ensure that customizables are relabeled as well in scenarios where filesystems are labeled but where SELinux is disabled.
> 
> V3: Fixes file test that was introduced in V2.
> 
> V4: Remove file tests and instead rely on which
> 
> Signed-off-by: Dominick Grift <dominick.grift@defensec.nl>
> ---
>  scripts/selinux/install_policy.sh | 23 +++++++++++++----------
>  scripts/selinux/mdp/mdp.c         |  1 +
>  2 files changed, 14 insertions(+), 10 deletions(-)
> 
> diff --git a/scripts/selinux/install_policy.sh b/scripts/selinux/install_policy.sh
> index 0b86c47baf7d..773377838670 100755
> --- a/scripts/selinux/install_policy.sh
> +++ b/scripts/selinux/install_policy.sh
> @@ -6,25 +6,28 @@ if [ `id -u` -ne 0 ]; then
>  fi
>  SF=`which setfiles`
>  if [ $? -eq 1 ]; then
> -	if [ -f /sbin/setfiles ]; then
> -		SF="/usr/setfiles"
> -	else
> -		echo "no selinux tools installed: setfiles"
> -		exit 1
> -	fi
> +	echo "no selinux tools installed: setfiles"
> +	exit 1
>  fi
>  
>  cd mdp
>  
>  CP=`which checkpolicy`
> +if [ $? -eq 1 ]; then
> +	echo "no selinux tools installed: checkpolicy"
> +	exit 1
> +fi
>  VERS=`$CP -V | awk '{print $1}'`
>  
>  ./mdp policy.conf file_contexts
> -$CP -o policy.$VERS policy.conf
> +$CP -U allow -o policy.$VERS policy.conf
>  
>  mkdir -p /etc/selinux/dummy/policy
>  mkdir -p /etc/selinux/dummy/contexts/files
>  
> +echo "__default__:user_u" > /etc/selinux/dummy/seusers
> +echo "base_r:base_t" > /etc/selinux/dummy/contexts/failsafe_context
> +
>  cp file_contexts /etc/selinux/dummy/contexts/files
>  cp dbus_contexts /etc/selinux/dummy/contexts
>  cp policy.$VERS /etc/selinux/dummy/policy
> @@ -55,15 +58,15 @@ else
>  fi
>  
>  cd /etc/selinux/dummy/contexts/files
> -$SF file_contexts /
> +$SF -F file_contexts /
>  
>  mounts=`cat /proc/$$/mounts | egrep "ext2|ext3|xfs|jfs|ext4|ext4dev|gfs2" | awk '{ print $2 '}`
> -$SF file_contexts $mounts
> +$SF -F file_contexts $mounts
>  
>  
>  dodev=`cat /proc/$$/mounts | grep "/dev "`
>  if [ "eq$dodev" != "eq" ]; then
>  	mount --move /dev /mnt
> -	$SF file_contexts /dev
> +	$SF -F file_contexts /dev
>  	mount --move /mnt /dev
>  fi
> diff --git a/scripts/selinux/mdp/mdp.c b/scripts/selinux/mdp/mdp.c
> index 073fe7537f6c..cf06d5694cbc 100644
> --- a/scripts/selinux/mdp/mdp.c
> +++ b/scripts/selinux/mdp/mdp.c
> @@ -131,6 +131,7 @@ int main(int argc, char *argv[])
>  
>  	fprintf(fout, "fs_use_trans mqueue user_u:base_r:base_t;\n");
>  	fprintf(fout, "fs_use_trans devpts user_u:base_r:base_t;\n");
> +	fprintf(fout, "fs_use_trans devtmpfs user_u:base_r:base_t;\n");
>  	fprintf(fout, "fs_use_trans hugetlbfs user_u:base_r:base_t;\n");
>  	fprintf(fout, "fs_use_trans tmpfs user_u:base_r:base_t;\n");
>  	fprintf(fout, "fs_use_trans shm user_u:base_r:base_t;\n");
> -- 
> 2.21.0.rc1
>
diff mbox series

Patch

diff --git a/scripts/selinux/install_policy.sh b/scripts/selinux/install_policy.sh
index 0b86c47baf7d..773377838670 100755
--- a/scripts/selinux/install_policy.sh
+++ b/scripts/selinux/install_policy.sh
@@ -6,25 +6,28 @@  if [ `id -u` -ne 0 ]; then
 fi
 SF=`which setfiles`
 if [ $? -eq 1 ]; then
-	if [ -f /sbin/setfiles ]; then
-		SF="/usr/setfiles"
-	else
-		echo "no selinux tools installed: setfiles"
-		exit 1
-	fi
+	echo "no selinux tools installed: setfiles"
+	exit 1
 fi
 
 cd mdp
 
 CP=`which checkpolicy`
+if [ $? -eq 1 ]; then
+	echo "no selinux tools installed: checkpolicy"
+	exit 1
+fi
 VERS=`$CP -V | awk '{print $1}'`
 
 ./mdp policy.conf file_contexts
-$CP -o policy.$VERS policy.conf
+$CP -U allow -o policy.$VERS policy.conf
 
 mkdir -p /etc/selinux/dummy/policy
 mkdir -p /etc/selinux/dummy/contexts/files
 
+echo "__default__:user_u" > /etc/selinux/dummy/seusers
+echo "base_r:base_t" > /etc/selinux/dummy/contexts/failsafe_context
+
 cp file_contexts /etc/selinux/dummy/contexts/files
 cp dbus_contexts /etc/selinux/dummy/contexts
 cp policy.$VERS /etc/selinux/dummy/policy
@@ -55,15 +58,15 @@  else
 fi
 
 cd /etc/selinux/dummy/contexts/files
-$SF file_contexts /
+$SF -F file_contexts /
 
 mounts=`cat /proc/$$/mounts | egrep "ext2|ext3|xfs|jfs|ext4|ext4dev|gfs2" | awk '{ print $2 '}`
-$SF file_contexts $mounts
+$SF -F file_contexts $mounts
 
 
 dodev=`cat /proc/$$/mounts | grep "/dev "`
 if [ "eq$dodev" != "eq" ]; then
 	mount --move /dev /mnt
-	$SF file_contexts /dev
+	$SF -F file_contexts /dev
 	mount --move /mnt /dev
 fi
diff --git a/scripts/selinux/mdp/mdp.c b/scripts/selinux/mdp/mdp.c
index 073fe7537f6c..cf06d5694cbc 100644
--- a/scripts/selinux/mdp/mdp.c
+++ b/scripts/selinux/mdp/mdp.c
@@ -131,6 +131,7 @@  int main(int argc, char *argv[])
 
 	fprintf(fout, "fs_use_trans mqueue user_u:base_r:base_t;\n");
 	fprintf(fout, "fs_use_trans devpts user_u:base_r:base_t;\n");
+	fprintf(fout, "fs_use_trans devtmpfs user_u:base_r:base_t;\n");
 	fprintf(fout, "fs_use_trans hugetlbfs user_u:base_r:base_t;\n");
 	fprintf(fout, "fs_use_trans tmpfs user_u:base_r:base_t;\n");
 	fprintf(fout, "fs_use_trans shm user_u:base_r:base_t;\n");