"""Let's Encrypt CLI.""" # TODO: Sanity check all input. Be sure to avoid shell code etc... import argparse import atexit import functools import logging import logging.handlers import os import pkg_resources import sys import time import traceback import configargparse import zope.component import zope.interface.exceptions import zope.interface.verify import letsencrypt from letsencrypt import account from letsencrypt import configuration from letsencrypt import constants from letsencrypt import client from letsencrypt import errors from letsencrypt import interfaces from letsencrypt import le_util from letsencrypt import log from letsencrypt import reporter from letsencrypt.display import util as display_util from letsencrypt.display import ops as display_ops from letsencrypt.plugins import disco as plugins_disco logger = logging.getLogger(__name__) # Argparse's help formatting has a lot of unhelpful peculiarities, so we want # to replace as much of it as we can... # This is the stub to include in help generated by argparse SHORT_USAGE = """ letsencrypt [SUBCOMMAND] [options] [domains] The Let's Encrypt agent can obtain and install HTTPS/TLS/SSL certificates. By default, it will attempt to use a webserver both for obtaining and installing the cert. """ # This is the short help for letsencrypt --help, where we disable argparse # altogether USAGE = SHORT_USAGE + """Major SUBCOMMANDS are: (default) everything Obtain & install a cert in your current webserver auth Authenticate & obtain cert, but do not install it install Install a previously obtained cert in a server revoke Revoke a previously obtained certificate rollback Rollback server configuration changes made during install config_changes Show changes made to server config during installation Choice of server for authentication/installation: --apache Use the Apache plugin for authentication & installation --nginx Use the Nginx plugin for authentication & installation --standalone Run a standalone HTTPS server (for authentication only) OR: --authenticator standalone --installer nginx More detailed help: -h, --help [topic] print this message, or detailed help on a topic; the available topics are: all, apache, automation, nginx, paths, security, testing, or any of the subcommands """ def _find_domains(args, installer): if args.domains is None: domains = display_ops.choose_names(installer) else: domains = args.domains if not domains: raise errors.Error("Please specify --domains, or --installer that " "will help in domain names autodiscovery") return domains def _determine_account(args, config): """Determine which account to use. In order to make the renewer (configuration de/serialization) happy, if ``args.account`` is ``None``, it will be updated based on the user input. Same for ``args.email``. :param argparse.Namespace args: CLI arguments :param letsencrypt.interface.IConfig config: Configuration object :param .AccountStorage account_storage: Account storage. :returns: Account and optionally ACME client API (biproduct of new registration). :rtype: `tuple` of `letsencrypt.account.Account` and `acme.client.Client` """ account_storage = account.AccountFileStorage(config) acme = None if args.account is not None: acc = account_storage.load(args.account) else: accounts = account_storage.find_all() if len(accounts) > 1: acc = display_ops.choose_account(accounts) elif len(accounts) == 1: acc = accounts[0] else: # no account registered yet if args.email is None: args.email = display_ops.get_email() if not args.email: # get_email might return "" args.email = None def _tos_cb(regr): if args.tos: return True msg = ("Please read the Terms of Service at {0}. You " "must agree in order to register with the ACME " "server at {1}".format( regr.terms_of_service, config.server)) return zope.component.getUtility(interfaces.IDisplay).yesno( msg, "Agree", "Cancel") try: acc, acme = client.register( config, account_storage, tos_cb=_tos_cb) except errors.Error as error: logger.debug(error, exc_info=True) raise errors.Error( "Unable to register an account with ACME server") args.account = acc.id return acc, acme def _init_le_client(args, config, authenticator, installer): if authenticator is not None: # if authenticator was given, then we will need account... acc, acme = _determine_account(args, config) logger.debug("Picked account: %r", acc) # XXX #crypto_util.validate_key_csr(acc.key) else: acc, acme = None, None return client.Client(config, acc, authenticator, installer, acme=acme) def run(args, config, plugins): """Obtain a certificate and install.""" if args.configurator is not None and (args.installer is not None or args.authenticator is not None): return ("Either --configurator or --authenticator/--installer" "pair, but not both, is allowed") if args.authenticator is not None or args.installer is not None: installer = display_ops.pick_installer( config, args.installer, plugins) authenticator = display_ops.pick_authenticator( config, args.authenticator, plugins) else: # TODO: this assumes that user doesn't want to pick authenticator # and installer separately... authenticator = installer = display_ops.pick_configurator( config, args.configurator, plugins) if installer is None or authenticator is None: return "Configurator could not be determined" domains = _find_domains(args, installer) # TODO: Handle errors from _init_le_client? le_client = _init_le_client(args, config, authenticator, installer) lineage = le_client.obtain_and_enroll_certificate( domains, authenticator, installer, plugins) if not lineage: return "Certificate could not be obtained" le_client.deploy_certificate( domains, lineage.privkey, lineage.cert, lineage.chain) le_client.enhance_config(domains, args.redirect) def auth(args, config, plugins): """Authenticate & obtain cert, but do not install it.""" # XXX: Update for renewer / RenewableCert if args.domains is not None and args.csr is not None: # TODO: --csr could have a priority, when --domains is # supplied, check if CSR matches given domains? return "--domains and --csr are mutually exclusive" authenticator = display_ops.pick_authenticator( config, args.authenticator, plugins) if authenticator is None: return "Authenticator could not be determined" if args.installer is not None: installer = display_ops.pick_installer(config, args.installer, plugins) else: installer = None # TODO: Handle errors from _init_le_client? le_client = _init_le_client(args, config, authenticator, installer) if args.csr is not None: certr, chain = le_client.obtain_certificate_from_csr(le_util.CSR( file=args.csr[0], data=args.csr[1], form="der")) le_client.save_certificate( certr, chain, args.cert_path, args.chain_path) else: domains = _find_domains(args, installer) if not le_client.obtain_and_enroll_certificate( domains, authenticator, installer, plugins): return "Certificate could not be obtained" def install(args, config, plugins): """Install a previously obtained cert in a server.""" # XXX: Update for renewer/RenewableCert installer = display_ops.pick_installer(config, args.installer, plugins) if installer is None: return "Installer could not be determined" domains = _find_domains(args, installer) le_client = _init_le_client( args, config, authenticator=None, installer=installer) assert args.cert_path is not None # required=True in the subparser le_client.deploy_certificate( domains, args.key_path, args.cert_path, args.chain_path) le_client.enhance_config(domains, args.redirect) def revoke(args, unused_config, unused_plugins): """Revoke a previously obtained certificate.""" if args.cert_path is None and args.key_path is None: return "At least one of --cert-path or --key-path is required" # This depends on the renewal config and cannot be completed yet. zope.component.getUtility(interfaces.IDisplay).notification( "Revocation is not available with the new Boulder server yet.") #client.revoke(args.installer, config, plugins, args.no_confirm, # args.cert_path, args.key_path) def rollback(args, config, plugins): """Rollback server configuration changes made during install.""" client.rollback(args.installer, args.checkpoints, config, plugins) def config_changes(unused_args, config, unused_plugins): """Show changes made to server config during installation View checkpoints and associated configuration changes. """ client.view_config_changes(config) def plugins_cmd(args, config, plugins): # TODO: Use IDisplay rather than print """List server software plugins.""" logger.debug("Expected interfaces: %s", args.ifaces) ifaces = [] if args.ifaces is None else args.ifaces filtered = plugins.ifaces(ifaces) logger.debug("Filtered plugins: %r", filtered) if not args.init and not args.prepare: print str(filtered) return filtered.init(config) verified = filtered.verify(ifaces) logger.debug("Verified plugins: %r", verified) if not args.prepare: print str(verified) return verified.prepare() available = verified.available() logger.debug("Prepared plugins: %s", available) print str(available) def read_file(filename, mode="rb"): """Returns the given file's contents. :param str filename: Filename :param str mode: open mode (see `open`) :returns: A tuple of filename and its contents :rtype: tuple :raises argparse.ArgumentTypeError: File does not exist or is not readable. """ try: return filename, open(filename, mode).read() except IOError as exc: raise argparse.ArgumentTypeError(exc.strerror) def flag_default(name): """Default value for CLI flag.""" return constants.CLI_DEFAULTS[name] def config_help(name, hidden=False): """Help message for `.IConfig` attribute.""" if hidden: return argparse.SUPPRESS else: return interfaces.IConfig[name].__doc__ class SilentParser(object): # pylint: disable=too-few-public-methods """Silent wrapper around argparse. A mini parser wrapper that doesn't print help for its arguments. This is needed for the use of callbacks to define arguments within plugins. """ def __init__(self, parser): self.parser = parser def add_argument(self, *args, **kwargs): """Wrap, but silence help""" kwargs["help"] = argparse.SUPPRESS self.parser.add_argument(*args, **kwargs) HELP_TOPICS = ["all", "security", "paths", "automation", "testing", "plugins"] class HelpfulArgumentParser(object): """Argparse Wrapper. This class wraps argparse, adding the ability to make --help less verbose, and request help on specific subcategories at a time, eg 'letsencrypt --help security' for security options. """ def __init__(self, args, plugins): self.args = args plugin_names = [name for name, _p in plugins.iteritems()] self.help_topics = HELP_TOPICS + plugin_names + [None] self.parser = configargparse.ArgParser( usage=SHORT_USAGE, formatter_class=argparse.ArgumentDefaultsHelpFormatter, args_for_setting_config_path=["-c", "--config"], default_config_files=flag_default("config_files")) # This is the only way to turn off overly verbose config flag documentation self.parser._add_config_file_help = False # pylint: disable=protected-access self.silent_parser = SilentParser(self.parser) help1 = self.prescan_for_flag("-h", self.help_topics) help2 = self.prescan_for_flag("--help", self.help_topics) assert max(True, "a") == "a", "Gravity changed direction" help_arg = max(help1, help2) if help_arg == True: # just --help with no topic; avoid argparse altogether print USAGE sys.exit(0) self.visible_topics = self.determine_help_topics(help_arg) #print self.visible_topics self.groups = {} # elements are added by .add_group() def prescan_for_flag(self, flag, possible_arguments): """Checks cli input for flags. Check for a flag, which accepts a fixed set of possible arguments, in the command line; we will use this information to configure argparse's help correctly. Return the flag's argument, if it has one that matches the sequence @possible_arguments; otherwise return whether the flag is present. """ if flag not in self.args: return False pos = self.args.index(flag) try: nxt = self.args[pos + 1] if nxt in possible_arguments: return nxt except IndexError: pass return True def add(self, topic, *args, **kwargs): """Add a new command line argument. @topic is required, to indicate which part of the help will document it, but can be None for `always documented'. """ if self.visible_topics[topic]: if topic in self.groups: group = self.groups[topic] group.add_argument(*args, **kwargs) else: self.parser.add_argument(*args, **kwargs) else: kwargs["help"] = argparse.SUPPRESS self.parser.add_argument(*args, **kwargs) def add_group(self, topic, **kwargs): """ This has to be called once for every topic; but we leave those calls next to the argument definitions for clarity. Return something arguments can be added to if necessary, either the parser or an argument group. """ if self.visible_topics[topic]: #print "Adding visible group " + topic group = self.parser.add_argument_group(topic, **kwargs) self.groups[topic] = group return group else: #print "Invisible group " + topic return self.silent_parser def add_plugin_args(self, plugins): """ Let each of the plugins add its own command line arguments, which may or may not be displayed as help topics. """ for name, plugin_ep in plugins.iteritems(): parser_or_group = self.add_group(name, description=plugin_ep.description) #print parser_or_group plugin_ep.plugin_cls.inject_parser_options(parser_or_group, name) def determine_help_topics(self, chosen_topic): """ The user may have requested help on a topic, return a dict of which topics to display. @chosen_topic has prescan_for_flag's return type :returns: dict """ # topics maps each topic to whether it should be documented by # argparse on the command line if chosen_topic == "all": return dict([(t, True) for t in self.help_topics]) elif not chosen_topic: return dict([(t, False) for t in self.help_topics]) else: return dict([(t, t == chosen_topic) for t in self.help_topics]) def create_parser(plugins, args): """Create parser.""" helpful = HelpfulArgumentParser(args, plugins) # --help is automatically provided by argparse helpful.add( None, "-v", "--verbose", dest="verbose_count", action="count", default=flag_default("verbose_count"), help="This flag can be used " "multiple times to incrementally increase the verbosity of output, " "e.g. -vvv.") helpful.add( None, "-t", "--text", dest="text_mode", action="store_true", help="Use the text output instead of the curses UI.") helpful.add(None, "-m", "--email", help=config_help("email")) # positional arg shadows --domains, instead of appending, and # --domains is useful, because it can be stored in config #for subparser in parser_run, parser_auth, parser_install: # subparser.add_argument("domains", nargs="*", metavar="domain") helpful.add(None, "-d", "--domains", metavar="DOMAIN", action="append") helpful.add_group( "automation", description="Arguments for automating execution & other tweaks") helpful.add( "automation", "--version", action="version", version="%(prog)s {0}".format(letsencrypt.__version__), help="show program's version number and exit") helpful.add( "automation", "--no-confirm", dest="no_confirm", action="store_true", help="Turn off confirmation screens, currently used for --revoke") helpful.add( "automation", "--agree-eula", dest="eula", action="store_true", help="Agree to the Let's Encrypt Developer Preview EULA") helpful.add( "automation", "--agree-tos", dest="tos", action="store_true", help="Agree to the Let's Encrypt Subscriber Agreement") helpful.add( "automation", "--account", metavar="ACCOUNT_ID", help="Account ID to use") helpful.add_group( "testing", description="The following flags are meant for " "testing purposes only! Do NOT change them, unless you " "really know what you're doing!") helpful.add( "testing", "--debug", action="store_true", help="Show tracebacks if the program exits abnormally") helpful.add( "testing", "--no-verify-ssl", action="store_true", help=config_help("no_verify_ssl"), default=flag_default("no_verify_ssl")) helpful.add( # TODO: apache plugin does NOT respect it (#479) "testing", "--dvsni-port", type=int, default=flag_default("dvsni_port"), help=config_help("dvsni_port")) helpful.add("testing", "--simple-http-port", type=int, help=config_help("simple_http_port")) helpful.add("testing", "--no-simple-http-tls", action="store_true", help=config_help("no_simple_http_tls")) helpful.add_group( "security", description="Security parameters & server settings") helpful.add( "security", "-B", "--rsa-key-size", type=int, metavar="N", default=flag_default("rsa_key_size"), help=config_help("rsa_key_size")) # TODO: resolve - assumes binary logic while client.py assumes ternary. helpful.add( "security", "-r", "--redirect", action="store_true", help="Automatically redirect all HTTP traffic to HTTPS for the newly " "authenticated vhost.") _paths_parser(helpful) # _plugins_parsing should be the last thing to act upon the main # parser (--help should display plugin-specific options last) _plugins_parsing(helpful, plugins) _create_subparsers(helpful) return helpful.parser def _create_subparsers(helpful): subparsers = helpful.parser.add_subparsers(metavar="SUBCOMMAND") def add_subparser(name, func): # pylint: disable=missing-docstring subparser = subparsers.add_parser( name, help=func.__doc__.splitlines()[0], description=func.__doc__) subparser.set_defaults(func=func) return subparser # the order of add_subparser() calls is important: it defines the # order in which subparser names will be displayed in --help add_subparser("run", run) parser_auth = add_subparser("auth", auth) parser_install = add_subparser("install", install) parser_revoke = add_subparser("revoke", revoke) parser_rollback = add_subparser("rollback", rollback) add_subparser("config_changes", config_changes) parser_plugins = add_subparser("plugins", plugins_cmd) parser_auth.add_argument( "--csr", type=read_file, help="Path to a Certificate Signing " "Request (CSR) in DER format.") parser_auth.add_argument( "--cert-path", default=flag_default("auth_cert_path"), help="When using --csr this is where certificate is saved.") parser_auth.add_argument( "--chain-path", default=flag_default("auth_chain_path"), help="When using --csr this is where certificate chain is saved.") parser_install.add_argument( "--cert-path", required=True, help="Path to a certificate that " "is going to be installed.") parser_install.add_argument( "--key-path", required=True, help="Accompynying private key") parser_install.add_argument( "--chain-path", help="Accompanying path to a certificate chain.") parser_revoke.add_argument( "--cert-path", type=read_file, help="Revoke a specific certificate.") parser_revoke.add_argument( "--key-path", type=read_file, help="Revoke all certs generated by the provided authorized key.") parser_rollback.add_argument( "--checkpoints", type=int, metavar="N", default=flag_default("rollback_checkpoints"), help="Revert configuration N number of checkpoints.") parser_plugins.add_argument( "--init", action="store_true", help="Initialize plugins.") parser_plugins.add_argument( "--prepare", action="store_true", help="Initialize and prepare plugins.") parser_plugins.add_argument( "--authenticators", action="append_const", dest="ifaces", const=interfaces.IAuthenticator, help="Limit to authenticator plugins only.") parser_plugins.add_argument( "--installers", action="append_const", dest="ifaces", const=interfaces.IInstaller, help="Limit to installer plugins only.") def _paths_parser(helpful): add = helpful.add helpful.add_group( "paths", description="Arguments changing execution paths & servers") add("paths", "--config-dir", default=flag_default("config_dir"), help=config_help("config_dir")) add("paths", "--work-dir", default=flag_default("work_dir"), help=config_help("work_dir")) add("paths", "--logs-dir", default=flag_default("logs_dir"), help="Logs directory.") add("paths", "--server", default=flag_default("server"), help=config_help("server")) def _plugins_parsing(helpful, plugins): helpful.add_group( "plugins", description="Let's Encrypt client supports an " "extensible plugins architecture. See '%(prog)s plugins' for a " "list of all available plugins and their names. You can force " "a particular plugin by setting options provided below. Futher " "down this help message you will find plugin-specific options " "(prefixed by --{plugin_name}).") helpful.add( "plugins", "-a", "--authenticator", help="Authenticator plugin name.") helpful.add( "plugins", "-i", "--installer", help="Installer plugin name.") helpful.add( "plugins", "--configurator", help="Name of the plugin that is " "both an authenticator and an installer. Should not be used " "together with --authenticator or --installer.") # things should not be reorder past/pre this comment: # plugins_group should be displayed in --help before plugin # specific groups (so that plugins_group.description makes sense) helpful.add_plugin_args(plugins) def _setup_logging(args): level = -args.verbose_count * 10 fmt = "%(asctime)s:%(levelname)s:%(name)s:%(message)s" if args.text_mode: handler = logging.StreamHandler() handler.setFormatter(logging.Formatter(fmt)) else: handler = log.DialogHandler() # dialog box is small, display as less as possible handler.setFormatter(logging.Formatter("%(message)s")) handler.setLevel(level) # TODO: use fileConfig? # unconditionally log to file for debugging purposes # TODO: change before release? log_file_name = os.path.join(args.logs_dir, 'letsencrypt.log') file_handler = logging.handlers.RotatingFileHandler( log_file_name, maxBytes=2**20, backupCount=10) # rotate on each invocation, rollover only possible when maxBytes # is nonzero and backupCount is nonzero, so we set maxBytes as big # as possible not to overrun in single CLI invocation (1MB). file_handler.doRollover() # TODO: creates empty letsencrypt.log.1 file file_handler.setLevel(logging.DEBUG) file_handler_formatter = logging.Formatter(fmt=fmt) file_handler_formatter.converter = time.gmtime # don't use localtime file_handler.setFormatter(file_handler_formatter) root_logger = logging.getLogger() root_logger.setLevel(logging.DEBUG) # send all records to handlers root_logger.addHandler(handler) root_logger.addHandler(file_handler) logger.debug("Root logging level set at %d", level) logger.info("Saving debug log to %s", log_file_name) def _handle_exception(exc_type, exc_value, trace, args): """Logs exceptions and reports them to the user. Args is used to determine how to display exceptions to the user. In general, if args.debug is True, then the full exception and traceback is shown to the user, otherwise it is suppressed. If args itself is None, then the traceback and exception is attempted to be written to a logfile. If this is successful, the traceback is suppressed, otherwise it is shown to the user. sys.exit is always called with a nonzero status. """ logger.debug( "Exiting abnormally:\n%s", "".join(traceback.format_exception(exc_type, exc_value, trace))) if issubclass(exc_type, Exception) and (args is None or not args.debug): if args is None: logfile = "letsencrypt.log" try: with open(logfile, "w") as logfd: traceback.print_exception( exc_type, exc_value, trace, file=logfd) except: # pylint: disable=bare-except sys.exit("".join( traceback.format_exception(exc_type, exc_value, trace))) if issubclass(exc_type, errors.Error): sys.exit(exc_value) elif args is None: sys.exit( "An unexpected error occurred. Please see the logfile '{0}' " "for more details.".format(logfile)) else: sys.exit( "An unexpected error occurred. Please see the logfiles in {0} " "for more details.".format(args.logs_dir)) else: sys.exit("".join( traceback.format_exception(exc_type, exc_value, trace))) def main(cli_args=sys.argv[1:]): """Command line argument parsing and main script execution.""" sys.excepthook = functools.partial(_handle_exception, args=None) # note: arg parser internally handles --help (and exits afterwards) plugins = plugins_disco.PluginsRegistry.find_all() args = create_parser(plugins, cli_args).parse_args(cli_args) config = configuration.NamespaceConfig(args) # Setup logging ASAP, otherwise "No handlers could be found for # logger ..." TODO: this should be done before plugins discovery for directory in config.config_dir, config.work_dir: le_util.make_or_verify_dir( directory, constants.CONFIG_DIRS_MODE, os.geteuid()) # TODO: logs might contain sensitive data such as contents of the # private key! #525 le_util.make_or_verify_dir(args.logs_dir, 0o700, os.geteuid()) _setup_logging(args) # do not log `args`, as it contains sensitive data (e.g. revoke --key)! logger.debug("Arguments: %r", cli_args) logger.debug("Discovered plugins: %r", plugins) sys.excepthook = functools.partial(_handle_exception, args=args) # Displayer if args.text_mode: displayer = display_util.FileDisplay(sys.stdout) else: displayer = display_util.NcursesDisplay() zope.component.provideUtility(displayer) # Reporter report = reporter.Reporter() zope.component.provideUtility(report) atexit.register(report.atexit_print_messages) # TODO: remove developer EULA prompt for the launch if not config.eula: eula = pkg_resources.resource_string("letsencrypt", "EULA") if not zope.component.getUtility(interfaces.IDisplay).yesno( eula, "Agree", "Cancel"): raise errors.Error("Must agree to TOS") if not os.geteuid() == 0: logger.warning( "Root (sudo) is required to run most of letsencrypt functionality.") # check must be done after arg parsing as --help should work # w/o root; on the other hand, e.g. "letsencrypt run # --authenticator dns" or "letsencrypt plugins" does not # require root as well #return ( # "{0}Root is required to run letsencrypt. Please use sudo.{0}" # .format(os.linesep)) return args.func(args, config, plugins) if __name__ == "__main__": sys.exit(main()) # pragma: no cover