# Copyright (C) 2016 Canonical Ltd. # # Author: Ryan Harper # # This file is part of cloud-init. See LICENSE file for license information. """NTP: enable and configure ntp""" import copy import os from textwrap import dedent from cloudinit import log as logging from cloudinit import subp, temp_utils, templater, type_utils, util from cloudinit.config.schema import get_meta_doc, validate_cloudconfig_schema from cloudinit.settings import PER_INSTANCE LOG = logging.getLogger(__name__) frequency = PER_INSTANCE NTP_CONF = "/etc/ntp.conf" NR_POOL_SERVERS = 4 distros = [ "almalinux", "alpine", "centos", "cloudlinux", "debian", "eurolinux", "fedora", "miraclelinux", "openEuler", "opensuse", "photon", "rhel", "rocky", "sles", "ubuntu", "virtuozzo", ] NTP_CLIENT_CONFIG = { "chrony": { "check_exe": "chronyd", "confpath": "/etc/chrony.conf", "packages": ["chrony"], "service_name": "chrony", "template_name": "chrony.conf.{distro}", "template": None, }, "ntp": { "check_exe": "ntpd", "confpath": NTP_CONF, "packages": ["ntp"], "service_name": "ntp", "template_name": "ntp.conf.{distro}", "template": None, }, "ntpdate": { "check_exe": "ntpdate", "confpath": NTP_CONF, "packages": ["ntpdate"], "service_name": "ntpdate", "template_name": "ntp.conf.{distro}", "template": None, }, "systemd-timesyncd": { "check_exe": "/lib/systemd/systemd-timesyncd", "confpath": "/etc/systemd/timesyncd.conf.d/cloud-init.conf", "packages": [], "service_name": "systemd-timesyncd", "template_name": "timesyncd.conf", "template": None, }, } # This is Distro-specific configuration overrides of the base config DISTRO_CLIENT_CONFIG = { "alpine": { "chrony": { "confpath": "/etc/chrony/chrony.conf", "service_name": "chronyd", }, "ntp": { "confpath": "/etc/ntp.conf", "packages": [], "service_name": "ntpd", }, }, "debian": { "chrony": { "confpath": "/etc/chrony/chrony.conf", }, }, "opensuse": { "chrony": { "service_name": "chronyd", }, "ntp": { "confpath": "/etc/ntp.conf", "service_name": "ntpd", }, "systemd-timesyncd": { "check_exe": "/usr/lib/systemd/systemd-timesyncd", }, }, "photon": { "chrony": { "service_name": "chronyd", }, "ntp": {"service_name": "ntpd", "confpath": "/etc/ntp.conf"}, "systemd-timesyncd": { "check_exe": "/usr/lib/systemd/systemd-timesyncd", "confpath": "/etc/systemd/timesyncd.conf", }, }, "rhel": { "ntp": { "service_name": "ntpd", }, "chrony": { "service_name": "chronyd", }, }, "sles": { "chrony": { "service_name": "chronyd", }, "ntp": { "confpath": "/etc/ntp.conf", "service_name": "ntpd", }, "systemd-timesyncd": { "check_exe": "/usr/lib/systemd/systemd-timesyncd", }, }, "ubuntu": { "chrony": { "confpath": "/etc/chrony/chrony.conf", }, }, } # The schema definition for each cloud-config module is a strict contract for # describing supported configuration parameters for each cloud-config section. # It allows cloud-config to validate and alert users to invalid or ignored # configuration options before actually attempting to deploy with said # configuration. meta = { "id": "cc_ntp", "name": "NTP", "title": "enable and configure ntp", "description": dedent( """\ Handle ntp configuration. If ntp is not installed on the system and ntp configuration is specified, ntp will be installed. If there is a default ntp config file in the image or one is present in the distro's ntp package, it will be copied to a file with ``.dist`` appended to the filename before any changes are made. A list of ntp pools and ntp servers can be provided under the ``ntp`` config key. If no ntp ``servers`` or ``pools`` are provided, 4 pools will be used in the format ``{0-3}.{distro}.pool.ntp.org``.""" ), "distros": distros, "examples": [ dedent( """\ # Override ntp with chrony configuration on Ubuntu ntp: enabled: true ntp_client: chrony # Uses cloud-init default chrony configuration """ ), dedent( """\ # Provide a custom ntp client configuration ntp: enabled: true ntp_client: myntpclient config: confpath: /etc/myntpclient/myntpclient.conf check_exe: myntpclientd packages: - myntpclient service_name: myntpclient template: | ## template:jinja # My NTP Client config {% if pools -%}# pools{% endif %} {% for pool in pools -%} pool {{pool}} iburst {% endfor %} {%- if servers %}# servers {% endif %} {% for server in servers -%} server {{server}} iburst {% endfor %} pools: [0.int.pool.ntp.org, 1.int.pool.ntp.org, ntp.myorg.org] servers: - ntp.server.local - ntp.ubuntu.com - 192.168.23.2""" ), ], "frequency": PER_INSTANCE, } schema = { "type": "object", "properties": { "ntp": { "type": ["object", "null"], "properties": { "pools": { "type": "array", "items": {"type": "string", "format": "hostname"}, "uniqueItems": True, "description": dedent( """\ List of ntp pools. If both pools and servers are empty, 4 default pool servers will be provided of the format ``{0-3}.{distro}.pool.ntp.org``. NOTE: for Alpine Linux when using the Busybox NTP client this setting will be ignored due to the limited functionality of Busybox's ntpd.""" ), }, "servers": { "type": "array", "items": {"type": "string", "format": "hostname"}, "uniqueItems": True, "description": dedent( """\ List of ntp servers. If both pools and servers are empty, 4 default pool servers will be provided with the format ``{0-3}.{distro}.pool.ntp.org``.""" ), }, "ntp_client": { "type": "string", "default": "auto", "description": dedent( """\ Name of an NTP client to use to configure system NTP. When unprovided or 'auto' the default client preferred by the distribution will be used. The following built-in client names can be used to override existing configuration defaults: chrony, ntp, ntpdate, systemd-timesyncd.""" ), }, "enabled": { "type": "boolean", "default": True, "description": dedent( """\ Attempt to enable ntp clients if set to True. If set to False, ntp client will not be configured or installed""" ), }, "config": { "description": dedent( """\ Configuration settings or overrides for the ``ntp_client`` specified.""" ), "type": ["object"], "properties": { "confpath": { "type": "string", "description": dedent( """\ The path to where the ``ntp_client`` configuration is written.""" ), }, "check_exe": { "type": "string", "description": dedent( """\ The executable name for the ``ntp_client``. For example, ntp service ``check_exe`` is 'ntpd' because it runs the ntpd binary.""" ), }, "packages": { "type": "array", "items": { "type": "string", }, "uniqueItems": True, "description": dedent( """\ List of packages needed to be installed for the selected ``ntp_client``.""" ), }, "service_name": { "type": "string", "description": dedent( """\ The systemd or sysvinit service name used to start and stop the ``ntp_client`` service.""" ), }, "template": { "type": "string", "description": dedent( """\ Inline template allowing users to define their own ``ntp_client`` configuration template. The value must start with '## template:jinja' to enable use of templating support. """ ), }, }, # Don't use REQUIRED_NTP_CONFIG_KEYS to allow for override # of builtin client values. "minProperties": 1, # If we have config, define something "additionalProperties": False, }, }, "additionalProperties": False, } }, } REQUIRED_NTP_CONFIG_KEYS = frozenset( ["check_exe", "confpath", "packages", "service_name"] ) __doc__ = get_meta_doc(meta, schema) # Supplement python help() def distro_ntp_client_configs(distro): """Construct a distro-specific ntp client config dictionary by merging distro specific changes into base config. @param distro: String providing the distro class name. @returns: Dict of distro configurations for ntp clients. """ dcfg = DISTRO_CLIENT_CONFIG cfg = copy.copy(NTP_CLIENT_CONFIG) if distro in dcfg: cfg = util.mergemanydict([cfg, dcfg[distro]], reverse=True) return cfg def select_ntp_client(ntp_client, distro): """Determine which ntp client is to be used, consulting the distro for its preference. @param ntp_client: String name of the ntp client to use. @param distro: Distro class instance. @returns: Dict of the selected ntp client or {} if none selected. """ # construct distro-specific ntp_client_config dict distro_cfg = distro_ntp_client_configs(distro.name) # user specified client, return its config if ntp_client and ntp_client != "auto": LOG.debug( 'Selected NTP client "%s" via user-data configuration', ntp_client ) return distro_cfg.get(ntp_client, {}) # default to auto if unset in distro distro_ntp_client = distro.get_option("ntp_client", "auto") clientcfg = {} if distro_ntp_client == "auto": for client in distro.preferred_ntp_clients: cfg = distro_cfg.get(client) if subp.which(cfg.get("check_exe")): LOG.debug( 'Selected NTP client "%s", already installed', client ) clientcfg = cfg break if not clientcfg: client = distro.preferred_ntp_clients[0] LOG.debug( 'Selected distro preferred NTP client "%s", not yet installed', client, ) clientcfg = distro_cfg.get(client) else: LOG.debug( 'Selected NTP client "%s" via distro system config', distro_ntp_client, ) clientcfg = distro_cfg.get(distro_ntp_client, {}) return clientcfg def install_ntp_client(install_func, packages=None, check_exe="ntpd"): """Install ntp client package if not already installed. @param install_func: function. This parameter is invoked with the contents of the packages parameter. @param packages: list. This parameter defaults to ['ntp']. @param check_exe: string. The name of a binary that indicates the package the specified package is already installed. """ if subp.which(check_exe): return if packages is None: packages = ["ntp"] install_func(packages) def rename_ntp_conf(confpath=None): """Rename any existing ntp client config file @param confpath: string. Specify a path to an existing ntp client configuration file. """ if os.path.exists(confpath): util.rename(confpath, confpath + ".dist") def generate_server_names(distro): """Generate a list of server names to populate an ntp client configuration file. @param distro: string. Specify the distro name @returns: list: A list of strings representing ntp servers for this distro. """ names = [] pool_distro = distro if distro == "sles": # For legal reasons x.pool.sles.ntp.org does not exist, # use the opensuse pool pool_distro = "opensuse" elif distro == "alpine" or distro == "eurolinux": # Alpine-specific pool (i.e. x.alpine.pool.ntp.org) does not exist # so use general x.pool.ntp.org instead. The same applies to EuroLinux pool_distro = "" for x in range(0, NR_POOL_SERVERS): names.append( ".".join( [n for n in [str(x)] + [pool_distro] + ["pool.ntp.org"] if n] ) ) return names def write_ntp_config_template( distro_name, service_name=None, servers=None, pools=None, path=None, template_fn=None, template=None, ): """Render a ntp client configuration for the specified client. @param distro_name: string. The distro class name. @param service_name: string. The name of the NTP client service. @param servers: A list of strings specifying ntp servers. Defaults to empty list. @param pools: A list of strings specifying ntp pools. Defaults to empty list. @param path: A string to specify where to write the rendered template. @param template_fn: A string to specify the template source file. @param template: A string specifying the contents of the template. This content will be written to a temporary file before being used to render the configuration file. @raises: ValueError when path is None. @raises: ValueError when template_fn is None and template is None. """ if not servers: servers = [] if not pools: pools = [] if ( len(servers) == 0 and distro_name == "alpine" and service_name == "ntpd" ): # Alpine's Busybox ntpd only understands "servers" configuration # and not "pool" configuration. servers = generate_server_names(distro_name) LOG.debug("Adding distro default ntp servers: %s", ",".join(servers)) elif len(servers) == 0 and len(pools) == 0: pools = generate_server_names(distro_name) LOG.debug( "Adding distro default ntp pool servers: %s", ",".join(pools) ) if not path: raise ValueError("Invalid value for path parameter") if not template_fn and not template: raise ValueError("Not template_fn or template provided") params = {"servers": servers, "pools": pools} if template: tfile = temp_utils.mkstemp(prefix="template_name-", suffix=".tmpl") template_fn = tfile[1] # filepath is second item in tuple util.write_file(template_fn, content=template) templater.render_to_file(template_fn, path, params) # clean up temporary template if template: util.del_file(template_fn) def supplemental_schema_validation(ntp_config): """Validate user-provided ntp:config option values. This function supplements flexible jsonschema validation with specific value checks to aid in triage of invalid user-provided configuration. @param ntp_config: Dictionary of configuration value under 'ntp'. @raises: ValueError describing invalid values provided. """ errors = [] missing = REQUIRED_NTP_CONFIG_KEYS.difference(set(ntp_config.keys())) if missing: keys = ", ".join(sorted(missing)) errors.append( "Missing required ntp:config keys: {keys}".format(keys=keys) ) elif not any( [ntp_config.get("template"), ntp_config.get("template_name")] ): errors.append( "Either ntp:config:template or ntp:config:template_name values" " are required" ) for key, value in sorted(ntp_config.items()): keypath = "ntp:config:" + key if key == "confpath": if not all([value, isinstance(value, str)]): errors.append( "Expected a config file path {keypath}." " Found ({value})".format(keypath=keypath, value=value) ) elif key == "packages": if not isinstance(value, list): errors.append( "Expected a list of required package names for {keypath}." " Found ({value})".format(keypath=keypath, value=value) ) elif key in ("template", "template_name"): if value is None: # Either template or template_name can be none continue if not isinstance(value, str): errors.append( "Expected a string type for {keypath}." " Found ({value})".format(keypath=keypath, value=value) ) elif not isinstance(value, str): errors.append( "Expected a string type for {keypath}. Found ({value})".format( keypath=keypath, value=value ) ) if errors: raise ValueError( r"Invalid ntp configuration:\n{errors}".format( errors="\n".join(errors) ) ) def handle(name, cfg, cloud, log, _args): """Enable and configure ntp.""" if "ntp" not in cfg: LOG.debug( "Skipping module named %s, not present or disabled by cfg", name ) return ntp_cfg = cfg["ntp"] if ntp_cfg is None: ntp_cfg = {} # Allow empty config which will install the package # TODO drop this when validate_cloudconfig_schema is strict=True if not isinstance(ntp_cfg, (dict)): raise RuntimeError( "'ntp' key existed in config, but not a dictionary type," " is a {_type} instead".format(_type=type_utils.obj_name(ntp_cfg)) ) validate_cloudconfig_schema(cfg, schema) # Allow users to explicitly enable/disable enabled = ntp_cfg.get("enabled", True) if util.is_false(enabled): LOG.debug("Skipping module named %s, disabled by cfg", name) return # Select which client is going to be used and get the configuration ntp_client_config = select_ntp_client( ntp_cfg.get("ntp_client"), cloud.distro ) # Allow user ntp config to override distro configurations ntp_client_config = util.mergemanydict( [ntp_client_config, ntp_cfg.get("config", {})], reverse=True ) supplemental_schema_validation(ntp_client_config) rename_ntp_conf(confpath=ntp_client_config.get("confpath")) template_fn = None if not ntp_client_config.get("template"): template_name = ntp_client_config.get("template_name").replace( "{distro}", cloud.distro.name ) template_fn = cloud.get_template_filename(template_name) if not template_fn: msg = ( "No template found, not rendering %s" % ntp_client_config.get("template_name") ) raise RuntimeError(msg) write_ntp_config_template( cloud.distro.name, service_name=ntp_client_config.get("service_name"), servers=ntp_cfg.get("servers", []), pools=ntp_cfg.get("pools", []), path=ntp_client_config.get("confpath"), template_fn=template_fn, template=ntp_client_config.get("template"), ) install_ntp_client( cloud.distro.install_packages, packages=ntp_client_config["packages"], check_exe=ntp_client_config["check_exe"], ) try: cloud.distro.manage_service( "reload", ntp_client_config.get("service_name") ) except subp.ProcessExecutionError as e: LOG.exception("Failed to reload/start ntp service: %s", e) raise # vi: ts=4 expandtab