Security-Enhanced Linux secures the ssh_keysign processes via flexible mandatory access control.
The ssh_keysign processes execute with the ssh_keysign_t SELinux type. You can check if you have these processes running by executing the ps command with the -Z qualifier.
For example:
ps -eZ | grep ssh_keysign_t
The ssh_keysign_t SELinux type can be entered via the ssh_keysign_exec_t file type.
The default entrypoint paths for the ssh_keysign_t domain are the following:
/usr/lib/openssh/ssh-keysign, /usr/libexec/openssh/ssh-keysign
You can see the context of a process using the -Z option to psP Policy governs the access confined processes have to files. SELinux ssh_keysign policy is very flexible allowing users to setup their ssh_keysign processes in as secure a method as possible.
The following process types are defined for ssh_keysign:
ssh_keysign_t
Note: semanage permissive -a ssh_keysign_t can be used to make the process type ssh_keysign_t permissive. SELinux does not deny access to permissive process types, but the AVC (SELinux denials) messages are still generated.
If you want to allow host key based authentication, you must turn on the ssh_keysign boolean. Disabled by default.
setsebool -P ssh_keysign 1
If you want to allow all domains to execute in fips_mode, you must turn on the fips_mode boolean. Enabled by default.
setsebool -P fips_mode 1
If you want to allow confined applications to use nscd shared memory, you must turn on the nscd_use_shm boolean. Enabled by default.
setsebool -P nscd_use_shm 1
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 ssh_keysign policy is very flexible allowing users to setup their ssh_keysign processes in as secure a method as possible.
The following file types are defined for ssh_keysign:
ssh_keysign_exec_t
- Set files with the ssh_keysign_exec_t type, if you want to transition an executable to the ssh_keysign_t domain.
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.
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 boolean can also be used to manipulate the booleans
system-config-selinux is a GUI tool available to customize SELinux policy settings.