From d4c10902026b76a6372cf738fc98860b29b39759 Mon Sep 17 00:00:00 2001 From: Daniil Baturin Date: Wed, 16 May 2018 16:01:38 +0200 Subject: T644: remove prefixing from all scripts and update environment variables with VyOS paths. --- src/conf_mode/ssh.py | 249 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 249 insertions(+) create mode 100755 src/conf_mode/ssh.py (limited to 'src/conf_mode/ssh.py') diff --git a/src/conf_mode/ssh.py b/src/conf_mode/ssh.py new file mode 100755 index 000000000..a4857bba9 --- /dev/null +++ b/src/conf_mode/ssh.py @@ -0,0 +1,249 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2018 VyOS maintainers and contributors +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 2 or later as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . +# +# + +import sys +import os + +import jinja2 + +from vyos.config import Config +from vyos import ConfigError + +config_file = r'/etc/ssh/sshd_config' + +# Please be careful if you edit the template. +config_tmpl = """ + +### Autogenerated by vyos-config-ssh.py ### + +# Non-configurable defaults +Protocol 2 +HostKey /etc/ssh/ssh_host_rsa_key +HostKey /etc/ssh/ssh_host_dsa_key +HostKey /etc/ssh/ssh_host_ecdsa_key +HostKey /etc/ssh/ssh_host_ed25519_key +UsePrivilegeSeparation yes +KeyRegenerationInterval 3600 +ServerKeyBits 1024 +SyslogFacility AUTH +LoginGraceTime 120 +StrictModes yes +RSAAuthentication yes +PubkeyAuthentication yes +IgnoreRhosts yes +RhostsRSAAuthentication no +HostbasedAuthentication no +PermitEmptyPasswords no +ChallengeResponseAuthentication no +X11Forwarding yes +X11DisplayOffset 10 +PrintMotd no +PrintLastLog yes +TCPKeepAlive yes +Banner /etc/issue.net +Subsystem sftp /usr/lib/openssh/sftp-server +UsePAM yes +HostKey /etc/ssh/ssh_host_key +PermitRootLogin no + +# Specifies whether sshd should look up the remote host name, +# and to check that the resolved host name for the remote IP +# address maps back to the very same IP address. +UseDNS {{ host_validation }} + +# Specifies the port number that sshd listens on. The default is 22. +# Multiple options of this type are permitted. +Port {{ port }} + +# Gives the verbosity level that is used when logging messages from sshd +LogLevel {{ log_level }} + +# Specifies whether password authentication is allowed +PasswordAuthentication {{ password_authentication }} + +{% if listen_on -%} +# Specifies the local addresses sshd should listen on +{% for a in listen_on -%} +ListenAddress {{ a }} +{% endfor -%} +{% endif %} + +{% if ciphers -%} +# Specifies the ciphers allowed. Multiple ciphers must be comma-separated. +# +# NOTE: As of now, there is no 'multi' node for 'ciphers', thus we have only one :/ +Ciphers {{ ciphers | join(",") }} +{% endif %} + +{% if mac -%} +# Specifies the available MAC (message authentication code) algorithms. The MAC +# algorithm is used for data integrity protection. Multiple algorithms must be +# comma-separated. +# +# NOTE: As of now, there is no 'multi' node for 'mac', thus we have only one :/ +MACs {{ mac | join(",") }} +{% endif %} + +{% if key_exchange -%} +# Specifies the available KEX (Key Exchange) algorithms. Multiple algorithms must +# be comma-separated. +# +# NOTE: As of now, there is no 'multi' node for 'key-exchange', thus we have only one :/ +KexAlgorithms {{ key_exchange | join(",") }} +{% endif %} + +{% if allow_users -%} +# This keyword can be followed by a list of user name patterns, separated by spaces. +# If specified, login is allowed only for user names that match one of the patterns. +# Only user names are valid, a numerical user ID is not recognized. +AllowUsers {{ allow_users | join(" ") }} +{% endif %} + +{% if allow_groups -%} +# This keyword can be followed by a list of group name patterns, separated by spaces. +# If specified, login is allowed only for users whose primary group or supplementary +# group list matches one of the patterns. Only group names are valid, a numerical group +# ID is not recognized. +AllowGroups {{ allow_groups | join(" ") }} +{% endif %} + +{% if deny_users -%} +# This keyword can be followed by a list of user name patterns, separated by spaces. +# Login is disallowed for user names that match one of the patterns. Only user names +# are valid, a numerical user ID is not recognized. +DenyUsers {{ deny_users | join(" ") }} +{% endif %} + +{% if deny_groups -%} +# This keyword can be followed by a list of group name patterns, separated by spaces. +# Login is disallowed for users whose primary group or supplementary group list matches +# one of the patterns. Only group names are valid, a numerical group ID is not recognized. +DenyGroups {{ deny_groups | join(" ") }} +{% endif %} +""" + +default_config_data = { + 'port' : '22', + 'log_level': 'INFO', + 'password_authentication': 'yes', + 'host_validation': 'yes' +} + +def get_config(): + ssh = default_config_data + conf = Config() + if not conf.exists('service ssh'): + return None + else: + conf.set_level('service ssh') + + if conf.exists('access-control allow user'): + allow_users = conf.return_values('access-control allow user') + ssh.setdefault('allow_users', allow_users) + + if conf.exists('access-control allow group'): + allow_groups = conf.return_values('access-control allow group') + ssh.setdefault('allow_groups', allow_groups) + + if conf.exists('access-control deny user'): + deny_users = conf.return_values('access-control deny user') + ssh.setdefault('deny_users', deny_users) + + if conf.exists('access-control deny group'): + deny_groups = conf.return_values('access-control deny group') + ssh.setdefault('deny_groups', deny_groups) + + if conf.exists('ciphers'): + ciphers = conf.return_values('ciphers') + ssh.setdefault('ciphers', ciphers) + + if conf.exists('disable-host-validation'): + ssh['host_validation'] = 'no' + + if conf.exists('disable-password-authentication'): + ssh['password_authentication'] = 'no' + + if conf.exists('key-exchange'): + kex = conf.return_values('key-exchange') + ssh.setdefault('key_exchange', kex) + + if conf.exists('listen-address'): + # We can listen on both IPv4 and IPv6 addresses + # Maybe there could be a check in the future if the configured IP address + # is configured on this system at all? + addresses = conf.return_values('listen-address') + listen = [] + + for addr in addresses: + listen.append(addr) + + ssh.setdefault('listen_on', listen) + + if conf.exists('loglevel'): + ssh['log_level'] = conf.return_value('loglevel') + + if conf.exists('mac'): + mac = conf.return_values('mac') + ssh.setdefault('mac', mac) + + if conf.exists('port'): + port = conf.return_value('port') + ssh.setdefault('port', port) + + return ssh + +def verify(ssh): + if ssh is None: + return None + + if 'loglevel' in ssh.keys(): + allowed_loglevel = 'QUIET, FATAL, ERROR, INFO, VERBOSE' + if not ssh['loglevel'] in allowed_loglevel: + raise ConfigError('loglevel must be one of "{0}"\n'.format(allowed_loglevel)) + + return None + +def generate(ssh): + if ssh is None: + return None + + tmpl = jinja2.Template(config_tmpl) + config_text = tmpl.render(ssh) + with open(config_file, 'w') as f: + f.write(config_text) + return None + +def apply(ssh): + if ssh is not None and 'port' in ssh.keys(): + os.system("sudo systemctl restart ssh") + else: + # SSH access is removed in the commit + os.system("sudo systemctl stop ssh") + os.unlink(config_file) + + return None + +if __name__ == '__main__': + try: + c = get_config() + verify(c) + generate(c) + apply(c) + except ConfigError as e: + print(e) + sys.exit(1) -- cgit v1.2.3