[PATCH] Add interface to allow relabeling of iso 9660 filesystems.

[PATCH] Add interface to allow relabeling of iso 9660 filesystems.

[Sugar, David]

I have a case where I'm labeling media with my own types to control
access.  But that is requiring that I relabel from iso9660_t to my
own type.  This interface allows that relabel.

type=AVC msg=audit(1551621984.372:919): avc:  denied  { relabelfrom } for  pid=9717 comm="mount" scontext=staff_u:staff_r:mymedia_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:iso9660_t:s0 tclass=filesystem permissive=0

Signed-off-by: Dave Sugar <dsugar@tresys.com>
---
 policy/modules/kernel/filesystem.if | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/policy/modules/kernel/filesystem.if b/policy/modules/kernel/filesystem.if
index 048b9d65..a22cb6ba 100644
--- a/policy/modules/kernel/filesystem.if
+++ b/policy/modules/kernel/filesystem.if
@@ -2505,6 +2505,25 @@ interface(`fs_remount_iso9660_fs',`
 	allow $1 iso9660_t:filesystem remount;
 ')
 
+########################################
+## <summary>
+##	Allow changing of the label of a
+##	filesystem with iso9660 type
+## </summary>
+## <param name="domain">
+##	<summary>
+##	Domain allowed access.
+##	</summary>
+## </param>
+#
+interface(`fs_relabelfrom_iso9660_fs',`
+	gen_require(`
+		type iso9660_t;
+	')
+
+	allow $1 iso9660_t:filesystem relabelfrom;
+')
+
 ########################################
 ## <summary>
 ##	Unmount an iso9660 filesystem, which
-- 
2.20.1

Re: [PATCH] Add interface to allow relabeling of iso 9660 filesystems.

[Dominick Grift]

"Sugar, David" <dsugar@tresys.com> writes:

> I have a case where I'm labeling media with my own types to control
> access.  But that is requiring that I relabel from iso9660_t to my
> own type.  This interface allows that relabel.

Not sure why you would want this as iso9600 is read-only any way, I
suppose you want to block read access for entities that can already read iso9660.

>
> type=AVC msg=audit(1551621984.372:919): avc:  denied  { relabelfrom } for  pid=9717 comm="mount" scontext=staff_u:staff_r:mymedia_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:iso9660_t:s0 tclass=filesystem permissive=0
>
> Signed-off-by: Dave Sugar <dsugar@tresys.com>
> ---
>  policy/modules/kernel/filesystem.if | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
>
> diff --git a/policy/modules/kernel/filesystem.if b/policy/modules/kernel/filesystem.if
> index 048b9d65..a22cb6ba 100644
> --- a/policy/modules/kernel/filesystem.if
> +++ b/policy/modules/kernel/filesystem.if
> @@ -2505,6 +2505,25 @@ interface(`fs_remount_iso9660_fs',`
>  	allow $1 iso9660_t:filesystem remount;
>  ')
>  
> +########################################
> +## <summary>
> +##	Allow changing of the label of a
> +##	filesystem with iso9660 type
> +## </summary>
> +## <param name="domain">
> +##	<summary>
> +##	Domain allowed access.
> +##	</summary>
> +## </param>
> +#
> +interface(`fs_relabelfrom_iso9660_fs',`
> +	gen_require(`
> +		type iso9660_t;
> +	')
> +
> +	allow $1 iso9660_t:filesystem relabelfrom;
> +')
> +
>  ########################################
>  ## <summary>
>  ##	Unmount an iso9660 filesystem, which

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Dominick Grift

Re: [PATCH] Add interface to allow relabeling of iso 9660 filesystems.

[Sugar, David]

On 3/6/19 3:20 AM, Dominick Grift wrote:
> "Sugar, David" <dsugar@tresys.com> writes:
> 
>> I have a case where I'm labeling media with my own types to control
>> access.  But that is requiring that I relabel from iso9660_t to my
>> own type.  This interface allows that relabel.
> 
> Not sure why you would want this as iso9600 is read-only any way, I
> suppose you want to block read access for entities that can already read iso9660.
> 

In what I am working on I have to support encrypted USB devices.  Many 
of these devices work by first presenting a read-only partition.  It 
shows up as /dev/sr#.  This partition is used to unlock the encrypted 
partition (which then shows up as /dev/sd*#).

When mounting the read-only partition I'm providing a specific context 
to the mount command.  I think during the mount it initially gets the 
context iso9660_t and then relabels from that to my context.  Note that 
I am not transitioning to the call to mount, but running mount in my domain.

And I kind of do want to keep other domains from accessing this mounted 
partition.

>>
>> type=AVC msg=audit(1551621984.372:919): avc:  denied  { relabelfrom } for  pid=9717 comm="mount" scontext=staff_u:staff_r:mymedia_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:iso9660_t:s0 tclass=filesystem permissive=0
>>
>> Signed-off-by: Dave Sugar <dsugar@tresys.com>
>> ---
>>   policy/modules/kernel/filesystem.if | 19 +++++++++++++++++++
>>   1 file changed, 19 insertions(+)
>>
>> diff --git a/policy/modules/kernel/filesystem.if b/policy/modules/kernel/filesystem.if
>> index 048b9d65..a22cb6ba 100644
>> --- a/policy/modules/kernel/filesystem.if
>> +++ b/policy/modules/kernel/filesystem.if
>> @@ -2505,6 +2505,25 @@ interface(`fs_remount_iso9660_fs',`
>>   	allow $1 iso9660_t:filesystem remount;
>>   ')
>>   
>> +########################################
>> +## <summary>
>> +##	Allow changing of the label of a
>> +##	filesystem with iso9660 type
>> +## </summary>
>> +## <param name="domain">
>> +##	<summary>
>> +##	Domain allowed access.
>> +##	</summary>
>> +## </param>
>> +#
>> +interface(`fs_relabelfrom_iso9660_fs',`
>> +	gen_require(`
>> +		type iso9660_t;
>> +	')
>> +
>> +	allow $1 iso9660_t:filesystem relabelfrom;
>> +')
>> +
>>   ########################################
>>   ## <summary>
>>   ##	Unmount an iso9660 filesystem, which
> 

Re: [PATCH] Add interface to allow relabeling of iso 9660 filesystems.

[Chris PeBenito]

On 3/5/19 5:32 PM, Sugar, David wrote:
> I have a case where I'm labeling media with my own types to control
> access.  But that is requiring that I relabel from iso9660_t to my
> own type.  This interface allows that relabel.
> 
> type=AVC msg=audit(1551621984.372:919): avc:  denied  { relabelfrom } for  pid=9717 comm="mount" scontext=staff_u:staff_r:mymedia_sudo_t:s0-s0:c0.c1023 tcontext=system_u:object_r:iso9660_t:s0 tclass=filesystem permissive=0
> 
> Signed-off-by: Dave Sugar <dsugar@tresys.com>
> ---
>   policy/modules/kernel/filesystem.if | 19 +++++++++++++++++++
>   1 file changed, 19 insertions(+)
> 
> diff --git a/policy/modules/kernel/filesystem.if b/policy/modules/kernel/filesystem.if
> index 048b9d65..a22cb6ba 100644
> --- a/policy/modules/kernel/filesystem.if
> +++ b/policy/modules/kernel/filesystem.if
> @@ -2505,6 +2505,25 @@ interface(`fs_remount_iso9660_fs',`
>   	allow $1 iso9660_t:filesystem remount;
>   ')
>   
> +########################################
> +## <summary>
> +##	Allow changing of the label of a
> +##	filesystem with iso9660 type
> +## </summary>
> +## <param name="domain">
> +##	<summary>
> +##	Domain allowed access.
> +##	</summary>
> +## </param>
> +#
> +interface(`fs_relabelfrom_iso9660_fs',`
> +	gen_require(`
> +		type iso9660_t;
> +	')
> +
> +	allow $1 iso9660_t:filesystem relabelfrom;
> +')
> +
>   ########################################
>   ## <summary>
>   ##	Unmount an iso9660 filesystem, which

Merged.

-- 
Chris PeBenito