ssh_selinux

Section: ssh SELinux Policy documentation (8)
Updated: ssh
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NAME

ssh_selinux - Security Enhanced Linux Policy for the ssh processes

DESCRIPTION

SELinux Linux secures ssh (Secure shell client and server policy) processes via flexible mandatory access control.

BOOLEANS

SELinux policy is customizable based on least access required. ssh policy is extremely flexible and has several booleans that allow you to manipulate the policy and run ssh with the tightest access possible.

If you want to allow ssh with chroot env to read and write files in the user home directorie, you must turn on the ssh_chroot_rw_homedirs boolean.

setsebool -P ssh_chroot_rw_homedirs 1

If you want to allow ssh logins as sysadm_r:sysadm_, you must turn on the ssh_sysadm_login boolean.

setsebool -P ssh_sysadm_login 1

If you want to allow host key based authenticatio, you must turn on the allow_ssh_keysign boolean.

setsebool -P allow_ssh_keysign 1

If you want to allow fenced domain to execute ssh, you must turn on the fenced_can_ssh boolean.

setsebool -P fenced_can_ssh 1

FILE CONTEXTS

SELinux requires files to have an extended attribute to define the file type.

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 policy is very flexible allowing users to setup their ssh processes in as secure a method as possible.

The following file types are defined for ssh:

ssh_agent_exec_t

- Set files with the ssh_agent_exec_t type, if you want to transition an executable to the ssh_agent_t domain.

ssh_agent_tmp_t

- Set files with the ssh_agent_tmp_t type, if you want to store ssh agent temporary files in the /tmp directories.

ssh_exec_t

- Set files with the ssh_exec_t type, if you want to transition an executable to the ssh_t domain.

ssh_home_t

- Set files with the ssh_home_t type, if you want to store ssh files in the users home directory.

Paths:: /var/lib/gitolite/.ssh(/.*)?, /root/.shosts, /var/lib/amanda/.ssh(/.*)?, /root/.ssh(/.*)?

ssh_keygen_exec_t

- Set files with the ssh_keygen_exec_t type, if you want to transition an executable to the ssh_keygen_t domain.

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.

ssh_tmpfs_t

- Set files with the ssh_tmpfs_t type, if you want to store ssh files on a tmpfs file system.

sshd_exec_t

- Set files with the sshd_exec_t type, if you want to transition an executable to the sshd_t domain.

sshd_initrc_exec_t

- Set files with the sshd_initrc_exec_t type, if you want to transition an executable to the sshd_initrc_t domain.

sshd_key_t

- Set files with the sshd_key_t type, if you want to treat the files as sshd key data.

Paths:: /etc/ssh/ssh_host_rsa_key, /etc/ssh/ssh_host_rsa_key.pub, /etc/ssh/ssh_host_dsa_key.pub, /etc/ssh/ssh_host_key, /etc/ssh/ssh_host_dsa_key, /etc/ssh/ssh_host_key.pub, /etc/ssh/primes

sshd_keytab_t

- Set files with the sshd_keytab_t type, if you want to treat the files as kerberos keytab files.

sshd_tmpfs_t

- Set files with the sshd_tmpfs_t type, if you want to store sshd files on a tmpfs file system.

sshd_var_run_t

- Set files with the sshd_var_run_t type, if you want to store the sshd 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.

PORT TYPES

SELinux defines port types to represent TCP and UDP ports.

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 ssh policy is very flexible allowing users to setup their ssh processes in as secure a method as possible.

The following port types are defined for ssh:

ssh_port_t

Default Defined Ports: tcp 8021

PROCESS TYPES

SELinux defines process types (domains) for each process running on the system

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 policy is very flexible allowing users to setup their ssh processes in as secure a method as possible.

The following process types are defined for ssh:

ssh_keysign_t, ssh_keygen_t, ssh_t, sshd_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.

COMMANDS

semanage fcontext can also be used to manipulate default file context mappings.

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

semanage boolean can also be used to manipulate the booleans

system-config-selinux is a GUI tool available to customize SELinux policy settings.

AUTHOR

This manual page was autogenerated by genman.py.

This document was created by man2html, using the manual pages.
Time: 05:34:30 GMT, December 24, 2015