Source code for fabtools.ssh

OpenSSH tasks

This module provides tools to manage OpenSSH server and client.

from __future__ import with_statement

from fabric.api import hide, shell_env
from fabric.contrib.files import append, sed

from fabtools.service import is_running, restart
from fabtools.files import watch

[docs]def harden(allow_root_login=False, allow_password_auth=False, sshd_config='/etc/ssh/sshd_config'): """ Apply best practices for ssh security. See :func:`fabtools.ssh.disable_password_auth` and :func:`fabtools.ssh.disable_root_login` for a detailed description. :: import fabtools # This will apply all hardening techniques. fabtools.ssh.harden() # Only apply some of the techniques. fabtools.ssh.harden(allow_password_auth=True) # Override the sshd_config file location. fabtools.ssh.harden(sshd_config='/etc/sshd_config') """ if not allow_password_auth: disable_password_auth(sshd_config=sshd_config) if not allow_root_login: disable_root_login(sshd_config=sshd_config)
[docs]def disable_password_auth(sshd_config='/etc/ssh/sshd_config'): """ Do not allow users to use passwords to login via ssh. """ _update_ssh_setting(sshd_config, 'PasswordAuthentication', 'no')
[docs]def enable_password_auth(sshd_config='/etc/ssh/sshd_config'): """ Allow users to use passwords to login via ssh. """ _update_ssh_setting(sshd_config, 'PasswordAuthentication', 'yes')
[docs]def disable_root_login(sshd_config='/etc/ssh/sshd_config'): """ Do not allow root to login via ssh. """ _update_ssh_setting(sshd_config, 'PermitRootLogin', 'no')
[docs]def enable_root_login(sshd_config='/etc/ssh/sshd_config'): """ Allow root to login via ssh. """ _update_ssh_setting(sshd_config, 'PermitRootLogin', 'yes')
def _update_ssh_setting(sshd_config, name, value): """ Update a yes/no setting in the SSH config file """ with watch(sshd_config) as config_file: with shell_env(): # First try to change existing setting sed(sshd_config, r'^(\s*#\s*)?%s\s+(yes|no)' % name, '%s %s' % (name, value), use_sudo=True) # Then append setting if it's still missing _append(sshd_config, '%s %s' % (name, value), use_sudo=True) if config_file.changed and is_running('ssh'): restart('ssh') def _append(filename, regex, use_sudo): """ Less verbose append """ with hide('stdout', 'warnings'): return append(filename, regex, use_sudo=use_sudo)