Security-Enhanced Linux secures the postgrey processes via flexible mandatory access control.
You can see the context of a file using the -Z option to lsP Policy governs the access confined processes have to these files. SELinux postgrey policy is very flexible allowing users to setup their postgrey processes in as secure a method as possible.
The following file types are defined for postgrey:
postgrey_etc_t
- Set files with the postgrey_etc_t type, if you want to store postgrey files in the /etc directories.
postgrey_exec_t
- Set files with the postgrey_exec_t type, if you want to transition an executable to the postgrey_t domain.
postgrey_initrc_exec_t
- Set files with the postgrey_initrc_exec_t type, if you want to transition an executable to the postgrey_initrc_t domain.
postgrey_spool_t
- Set files with the postgrey_spool_t type, if you want to store the postgrey files under the /var/spool directory.
postgrey_var_lib_t
- Set files with the postgrey_var_lib_t type, if you want to store the postgrey files under the /var/lib directory.
postgrey_var_run_t
- Set files with the postgrey_var_run_t type, if you want to store the postgrey files under the /run directory.
Note: File context can be temporarily modified with the chcon command. If you want to permanently change the file context you need to use the semanage fcontext command. This will modify the SELinux labeling database. You will need to use restorecon to apply the labels.
You can see the types associated with a port by using the following command:
semanage port -l
Policy governs the access confined processes have to these ports. SELinux postgrey policy is very flexible allowing users to setup their postgrey processes in as secure a method as possible.
The following port types are defined for postgrey:
Default Defined Ports: tcp 60000
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux postgrey policy is very flexible allowing users to setup their postgrey processes in as secure a method as possible.
The following process types are defined for postgrey:
postgrey_t
Note: semanage permissive -a PROCESS_TYPE can be used to make a process type permissive. Permissive process types are not denied access by SELinux. AVC messages will still be generated.
The SELinux user type postgrey_t can manage files labeled with the following file types. The paths listed are the default paths for these file types. Note the processes UID still need to have DAC permissions.
postfix_spool_type
postgrey_spool_t
/var/spool/postfix/postgrey(/.*)?
postgrey_var_lib_t
/var/lib/postgrey(/.*)?
postgrey_var_run_t
/var/run/postgrey(/.*)?
/var/run/postgrey.pid
semanage permissive can also be used to manipulate whether or not a process type is permissive.
semanage module can also be used to enable/disable/install/remove policy modules.
semanage port can also be used to manipulate the port definitions
system-config-selinux is a GUI tool available to customize SELinux policy settings.