ssh_selinux(8) ssh SELinux Policy documentation ssh_selinux(8)NAMEssh_selinux - Security Enhanced Linux Policy for the ssh processes
DESCRIPTION
Security-Enhanced Linux secures the ssh processes via flexible manda‐
tory 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 bool‐
ean.
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
If you want to allow internal-sftp to read and write files in the user
ssh home directories, you must turn on the sftpd_write_ssh_home bool‐
ean.
setsebool -P sftpd_write_ssh_home 1
NSSWITCH DOMAIN
If you want to allow users to login using a sssd serve for the ssh_key‐
gen_t, sshd_t, ssh_t, you must turn on the authlogin_nsswitch_use_ldap
boolean.
setsebool -P authlogin_nsswitch_use_ldap 1
If you want to allow confined applications to run with kerberos for the
ssh_keygen_t, sshd_t, ssh_t, you must turn on the allow_kerberos bool‐
ean.
setsebool -P allow_kerberos 1
If you want to allow system to run with NI for the ssh_keygen_t,
sshd_t, ssh_t, you must turn on the allow_ypbind boolean.
setsebool -P allow_ypbind 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 ls
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 exe‐
cutable 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/nocpulse/.ssh(/.*)?, /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_key.pub, /etc/ssh/ssh_host_dsa_key,
/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.
Paths:
/var/run/sshd.init.pid, /var/run/sshd.pid
Note: File context can be temporarily modified with the chcon command.
If you want to permanantly change the file context you need to use the
semanage fcontext command. This will modify the SELinux labeling data‐
base. 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 22
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 ps
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:
sshd_sandbox_t, 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 pol‐
icy 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 pol‐
icy settings.
AUTHOR
This manual page was autogenerated by genman.py.
SEE ALSOselinux(8), ssh(8), semanage(8), restorecon(8), chcon(1) , setsebool(8)dwalsh@redhat.com ssh ssh_selinux(8)
