Subject: Re: [PATCH] Add interface xdm_run_domain
To:     "Sugar, David" <dsugar@tresys.com>,
        "selinux-refpolicy@vger.kernel.org" 
        <selinux-refpolicy@vger.kernel.org>
References: <20190404122900.8945-1-dsugar@tresys.com>
From:   Chris PeBenito <pebenito@ieee.org>
Message-ID: <6688c91f-9b5a-67f6-faf3-9aa5e3c55e65@ieee.org>
Date:   Sun, 7 Apr 2019 20:52:52 -0400
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On 4/4/19 8:29 AM, Sugar, David wrote:
> This interface is needed when using the various script options in
> lightdm (others?) configuration file.  I'm using with 'display-setup-script'
> and 'greeter-setup-script', but I suspect the same would be useful for
> 'display-stopped-script', 'session-cleanup-script' and others.  In these
> cases lightdm will be executing a configured script to perform some action
> during the specified phase of the greeter/session.  But without this interface
> there is no way to transition into a new domain to execute the action.

I'm reluctant to add this "reversed" interface.  In other cases, the 
domain (init, cron, inetd, etc.) is legitimately transitioning to many 
domains.  I don't see that here.


> Signed-off-by: Dave Sugar <dsugar@tresys.com>
> ---
>   policy/modules/services/xserver.if | 31 ++++++++++++++++++++++++++++++
>   1 file changed, 31 insertions(+)
> 
> diff --git a/policy/modules/services/xserver.if b/policy/modules/services/xserver.if
> index 854f3b90..2faef71d 100644
> --- a/policy/modules/services/xserver.if
> +++ b/policy/modules/services/xserver.if
> @@ -734,6 +734,37 @@ interface(`xserver_relabel_console_pipes',`
>   	allow $1 xconsole_device_t:fifo_file { getattr relabelfrom relabelto };
>   ')
>   
> +########################################
> +## <summary>
> +##	Allow display manager to execute the specified program in
> +##	the specified domain.
> +## </summary>
> +## <desc>
> +##	<p>
> +##	This is a interface to support the lightdm *-setup-script
> +##	options.  This will allow the command run by lightdm to
> +##	be run in a domain other than xdm_t.
> +##	</p>
> +## </desc>
> +## <param name="domain">
> +##	<summary>
> +##	Domain to execute in.
> +##	</summary>
> +## </param>
> +## <param name="entry_file">
> +##	<summary>
> +##	Domain entry point file.
> +##	</summary>
> +## </param>
> +#
> +interface(`xdm_run_domain',`
> +	gen_require(`
> +		type xdm_t;
> +	')
> +
> +	domtrans_pattern(xdm_t,$2,$1)
> +')
> +
>   ########################################
>   ## <summary>
>   ##	Use file descriptors for xdm.
> 


-- 
Chris PeBenito