/mandos/release : revision 22

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# This program is partly derived from an example program for an Avahi

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# service publisher, downloaded from

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# <http://avahi.org/wiki/PythonPublishExample>. This includes the

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# methods "add" and "remove" in the "AvahiService" class, the

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# "server_state_changed" and "entry_group_state_changed" functions,

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# and some lines in "main".

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# following functions: "add_service", "remove_service",

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# "server_state_changed", "entry_group_state_changed", and some lines

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# in "main".

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#

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# Everything else is

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# Påhlsson.

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#

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# This program is free software: you can redistribute it and/or modify

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# it under the terms of the GNU General Public License as published by

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# You should have received a copy of the GNU General Public License

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# along with this program. If not, see <http://www.gnu.org/licenses/>.

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#

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# Contact the authors at <mandos@fukt.bsnet.se>.

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# Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and

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# <https://www.fukt.bsnet.se/~teddy/>.

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#

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from __future__ import division

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from dbus.mainloop.glib import DBusGMainLoop

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import ctypes

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version = "1.0"

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# Brief description of the operation of this program:

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#

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# This server announces itself as a Zeroconf service. Connecting

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# clients use the TLS protocol, with the unusual quirk that this

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# server program acts as a TLS "client" while the connecting clients

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# acts as a TLS "server". The clients (acting as a TLS "server") must

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# supply an OpenPGP certificate, and the fingerprint of this

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# certificate is used by this server to look up (in a list read from a

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# file at start time) which binary blob to give the client. No other

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# authentication or authorization is done by this server.

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logger = logging.Logger('mandos')

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syslogger = logging.handlers.SysLogHandler\

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(facility = logging.handlers.SysLogHandler.LOG_DAEMON,

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address = "/dev/log")

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(facility = logging.handlers.SysLogHandler.LOG_DAEMON)

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syslogger.setFormatter(logging.Formatter\

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('Mandos: %(levelname)s: %(message)s'))

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('%(levelname)s: %(message)s'))

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logger.addHandler(syslogger)

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console = logging.StreamHandler()

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console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'

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' %(message)s'))

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logger.addHandler(console)

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class AvahiError(Exception):

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def __init__(self, value):

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self.value = value

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def __str__(self):

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return repr(self.value)

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class AvahiServiceError(AvahiError):

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pass

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class AvahiGroupError(AvahiError):

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pass

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class AvahiService(object):

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"""An Avahi (Zeroconf) service.

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Attributes:

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interface: integer; avahi.IF_UNSPEC or an interface index.

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Used to optionally bind to the specified interface.

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name: string; Example: 'Mandos'

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type: string; Example: '_mandos._tcp'.

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See <http://www.dns-sd.org/ServiceTypes.html>

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port: integer; what port to announce

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TXT: list of strings; TXT record for the service

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domain: string; Domain to publish on, default to .local if empty.

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host: string; Host to publish records for, default is localhost

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max_renames: integer; maximum number of renames

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rename_count: integer; counter so we only rename after collisions

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a sensible number of times

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"""

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def __init__(self, interface = avahi.IF_UNSPEC, name = None,

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type = None, port = None, TXT = None, domain = "",

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host = "", max_renames = 32768):

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self.interface = interface

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self.name = name

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self.type = type

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self.port = port

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if TXT is None:

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self.TXT = []

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else:

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self.TXT = TXT

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self.domain = domain

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self.host = host

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self.rename_count = 0

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self.max_renames = max_renames

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def rename(self):

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"""Derived from the Avahi example code"""

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if self.rename_count >= self.max_renames:

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logger.critical(u"No suitable service name found after %i"

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u" retries, exiting.", rename_count)

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raise AvahiServiceError("Too many renames")

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self.name = server.GetAlternativeServiceName(self.name)

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logger.info(u"Changing name to %r ...", str(self.name))

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syslogger.setFormatter(logging.Formatter\

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('Mandos (%s): %%(levelname)s:'

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' %%(message)s' % self.name))

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self.remove()

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self.add()

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self.rename_count += 1

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def remove(self):

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"""Derived from the Avahi example code"""

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if group is not None:

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group.Reset()

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def add(self):

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"""Derived from the Avahi example code"""

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global group

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if group is None:

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group = dbus.Interface\

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(bus.get_object(avahi.DBUS_NAME,

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server.EntryGroupNew()),

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avahi.DBUS_INTERFACE_ENTRY_GROUP)

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group.connect_to_signal('StateChanged',

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entry_group_state_changed)

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logger.debug(u"Adding service '%s' of type '%s' ...",

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service.name, service.type)

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group.AddService(

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self.interface, # interface

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avahi.PROTO_INET6, # protocol

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dbus.UInt32(0), # flags

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self.name, self.type,

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self.domain, self.host,

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dbus.UInt16(self.port),

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avahi.string_array_to_txt_array(self.TXT))

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group.Commit()

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del syslogger

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# This variable is used to optionally bind to a specified interface.

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# It is a global variable to fit in with the other variables from the

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# Avahi example code.

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serviceInterface = avahi.IF_UNSPEC

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# From the Avahi example code:

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group = None # our entry group

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serviceName = "Mandos"

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serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html

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servicePort = None # Not known at startup

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serviceTXT = [] # TXT record for the service

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domain = "" # Domain to publish on, default to .local

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host = "" # Host to publish records for, default to localhost

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group = None #our entry group

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rename_count = 12 # Counter so we only rename after collisions a

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# sensible number of times

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# End of Avahi example code

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fingerprint: string (40 or 32 hexadecimal digits); used to

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uniquely identify the client

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secret: bytestring; sent verbatim (over TLS) to client

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host: string; available for use by the checker command

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created: datetime.datetime(); object creation, not client host

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last_checked_ok: datetime.datetime() or None if not yet checked OK

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timeout: datetime.timedelta(); How long from last_checked_ok

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until this client is invalid

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fqdn: string (FQDN); available for use by the checker command

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created: datetime.datetime()

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last_seen: datetime.datetime() or None if not yet seen

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timeout: datetime.timedelta(); How long from last_seen until

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this client is invalid

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interval: datetime.timedelta(); How often to start a new checker

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stop_hook: If set, called by stop() as stop_hook(self)

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checker: subprocess.Popen(); a running checker process used

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to see if the client lives.

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'None' if no process is running.

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Is None if no process is running.

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checker_initiator_tag: a gobject event source tag, or None

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stop_initiator_tag: - '' -

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checker_callback_tag: - '' -

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checker_command: string; External command which is run to check if

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client lives. %() expansions are done at

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client lives. %()s expansions are done at

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runtime with vars(self) as dict, so that for

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instance %(name)s can be used in the command.

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Private attibutes:

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_timeout: Real variable for 'timeout'

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_interval: Real variable for 'interval'

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_timeout_milliseconds: Used when calling gobject.timeout_add()

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_timeout_milliseconds: Used by gobject.timeout_add()

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_interval_milliseconds: - '' -

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"""

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def _set_timeout(self, timeout):

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interval = property(lambda self: self._interval,

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_set_interval)

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del _set_interval

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def __init__(self, name = None, stop_hook=None, config={}):

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"""Note: the 'checker' key in 'config' sets the

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'checker_command' attribute and *not* the 'checker'

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attribute."""

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def __init__(self, name=None, options=None, stop_hook=None,

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fingerprint=None, secret=None, secfile=None,

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fqdn=None, timeout=None, interval=-1, checker=None):

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"""Note: the 'checker' argument sets the 'checker_command'

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attribute and not the 'checker' attribute.."""

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self.name = name

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logger.debug(u"Creating client %r", self.name)

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# Uppercase and remove spaces from fingerprint for later

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# comparison purposes with return value from the fingerprint()

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# function

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self.fingerprint = config["fingerprint"].upper()\

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.replace(u" ", u"")

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logger.debug(u" Fingerprint: %s", self.fingerprint)

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if "secret" in config:

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self.secret = config["secret"].decode(u"base64")

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elif "secfile" in config:

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sf = open(config["secfile"])

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# Uppercase and remove spaces from fingerprint

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# for later comparison purposes with return value of

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# the fingerprint() function

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self.fingerprint = fingerprint.upper().replace(u" ", u"")

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if secret:

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self.secret = secret.decode(u"base64")

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elif secfile:

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sf = open(secfile)

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self.secret = sf.read()

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sf.close()

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else:

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raise TypeError(u"No secret or secfile for client %s"

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% self.name)

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self.host = config.get("host", "")

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raise RuntimeError(u"No secret or secfile for client %s"

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% self.name)

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self.fqdn = fqdn # string

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self.created = datetime.datetime.now()

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self.last_checked_ok = None

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self.timeout = string_to_delta(config["timeout"])

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self.interval = string_to_delta(config["interval"])

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self.last_seen = None

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if timeout is None:

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self.timeout = options.timeout

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else:

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self.timeout = string_to_delta(timeout)

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if interval == -1:

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self.interval = options.interval

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else:

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self.interval = string_to_delta(interval)

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self.stop_hook = stop_hook

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self.checker = None

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self.checker_initiator_tag = None

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self.stop_initiator_tag = None

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self.checker_callback_tag = None

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self.check_command = config["checker"]

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self.check_command = checker

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def start(self):

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"""Start this client's checker and timeout hooks"""

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# Schedule a new checker to be started an 'interval' from now,

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self.stop)

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def stop(self):

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"""Stop this client.

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The possibility that a client might be restarted is left open,

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but not currently used."""

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The possibility that this client might be restarted is left

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open, but not currently used."""

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# If this client doesn't have a secret, it is already stopped.

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if hasattr(self, "secret") and self.secret:

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logger.info(u"Stopping client %s", self.name)

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if self.secret:

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logger.debug(u"Stopping client %s", self.name)

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self.secret = None

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else:

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return False

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if getattr(self, "stop_initiator_tag", False):

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if hasattr(self, "stop_initiator_tag") \

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and self.stop_initiator_tag:

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gobject.source_remove(self.stop_initiator_tag)

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self.stop_initiator_tag = None

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if getattr(self, "checker_initiator_tag", False):

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if hasattr(self, "checker_initiator_tag") \

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and self.checker_initiator_tag:

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gobject.source_remove(self.checker_initiator_tag)

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self.checker_initiator_tag = None

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self.stop_checker()

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self.checker = None

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if os.WIFEXITED(condition) \

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and (os.WEXITSTATUS(condition) == 0):

297

logger.info(u"Checker for %(name)s succeeded",

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vars(self))

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self.last_checked_ok = now

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logger.debug(u"Checker for %(name)s succeeded",

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vars(self))

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self.last_seen = now

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gobject.source_remove(self.stop_initiator_tag)

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self.stop_initiator_tag = gobject.timeout_add\

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(self._timeout_milliseconds,

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logger.warning(u"Checker for %(name)s crashed?",

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vars(self))

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else:

308

logger.info(u"Checker for %(name)s failed",

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vars(self))

248

logger.debug(u"Checker for %(name)s failed",

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vars(self))

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def start_checker(self):

311

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"""Start a new checker subprocess if one is not running.

312

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If a checker already exists, leave it running and do

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# is as it should be.

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if self.checker is None:

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try:

324

# In case check_command has exactly one % operator

325

command = self.check_command % self.host

264

command = self.check_command % self.fqdn

326

265

except TypeError:

327

# Escape attributes for the shell

328

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escaped_attrs = dict((key, re.escape(str(val)))

329

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for key, val in

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vars(self).iteritems())

331

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try:

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command = self.check_command % escaped_attrs

333

271

except TypeError, error:

334

logger.error(u'Could not format string "%s":'

335

u' %s', self.check_command, error)

272

logger.critical(u'Could not format string "%s":'

273

u' %s', self.check_command, error)

336

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return True # Try again later

337

275

try:

338

logger.info(u"Starting checker %r for %s",

339

command, self.name)

340

# We don't need to redirect stdout and stderr, since

341

# in normal mode, that is already done by daemon(),

342

# and in debug mode we don't want to. (Stdin is

343

# always replaced by /dev/null.)

344

self.checker = subprocess.Popen(command,

345

close_fds=True,

346

shell=True, cwd="/")

276

logger.debug(u"Starting checker %r for %s",

277

command, self.name)

278

self.checker = subprocess.\

279

Popen(command,

280

close_fds=True, shell=True,

281

cwd="/")

347

282

self.checker_callback_tag = gobject.child_watch_add\

348

283

(self.checker.pid,

349

284

self.checker_callback)

350

except OSError, error:

285

except subprocess.OSError, error:

351

286

logger.error(u"Failed to start subprocess: %s",

352

287

error)

353

288

# Re-run this periodically if run by gobject.timeout_add

357

292

if self.checker_callback_tag:

358

293

gobject.source_remove(self.checker_callback_tag)

359

294

self.checker_callback_tag = None

360

if getattr(self, "checker", None) is None:

295

if not hasattr(self, "checker") or self.checker is None:

361

296

return

362

logger.debug(u"Stopping checker for %(name)s", vars(self))

297

logger.debug("Stopping checker for %(name)s", vars(self))

363

298

try:

364

299

os.kill(self.checker.pid, signal.SIGTERM)

365

300

#os.sleep(0.5)

366

301

#if self.checker.poll() is None:

367

302

# os.kill(self.checker.pid, signal.SIGKILL)

368

303

except OSError, error:

369

if error.errno != errno.ESRCH: # No such process

304

if error.errno != errno.ESRCH:

370

305

raise

371

306

self.checker = None

372

def still_valid(self):

307

def still_valid(self, now=None):

373

308

"""Has the timeout not yet passed for this client?"""

374

now = datetime.datetime.now()

375

if self.last_checked_ok is None:

309

if now is None:

310

now = datetime.datetime.now()

311

if self.last_seen is None:

376

312

return now < (self.created + self.timeout)

377

313

else:

378

return now < (self.last_checked_ok + self.timeout)

314

return now < (self.last_seen + self.timeout)

379

315

380

316

381

317

def peer_certificate(session):

397

333

398

334

def fingerprint(openpgp):

399

335

"Convert an OpenPGP bytestring to a hexdigit fingerprint string"

336

# New empty GnuTLS certificate

337

crt = gnutls.library.types.gnutls_openpgp_crt_t()

338

gnutls.library.functions.gnutls_openpgp_crt_init\

339

(ctypes.byref(crt))

400

340

# New GnuTLS "datum" with the OpenPGP public key

401

341

datum = gnutls.library.types.gnutls_datum_t\

402

342

(ctypes.cast(ctypes.c_char_p(openpgp),

403

343

ctypes.POINTER(ctypes.c_ubyte)),

404

344

ctypes.c_uint(len(openpgp)))

405

# New empty GnuTLS certificate

406

crt = gnutls.library.types.gnutls_openpgp_crt_t()

407

gnutls.library.functions.gnutls_openpgp_crt_init\

408

(ctypes.byref(crt))

409

345

# Import the OpenPGP public key into the certificate

410

gnutls.library.functions.gnutls_openpgp_crt_import\

411

(crt, ctypes.byref(datum),

412

gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)

346

ret = gnutls.library.functions.gnutls_openpgp_crt_import\

347

(crt,

348

ctypes.byref(datum),

349

gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)

413

350

# New buffer for the fingerprint

414

351

buffer = ctypes.create_string_buffer(20)

415

352

buffer_length = ctypes.c_size_t()

431

368

Note: This will run in its own forked process."""

432

369

433

370

def handle(self):

434

logger.info(u"TCP connection from: %s",

371

logger.debug(u"TCP connection from: %s",

435

372

unicode(self.client_address))

436

session = gnutls.connection.ClientSession\

437

(self.request, gnutls.connection.X509Credentials())

438

439

line = self.request.makefile().readline()

440

logger.debug(u"Protocol version: %r", line)

441

try:

442

if int(line.strip().split()[0]) > 1:

443

raise RuntimeError

444

except (ValueError, IndexError, RuntimeError), error:

445

logger.error(u"Unknown protocol version: %s", error)

446

return

447

448

# Note: gnutls.connection.X509Credentials is really a generic

449

# GnuTLS certificate credentials object so long as no X.509

450

# keys are added to it. Therefore, we can use it here despite

451

# using OpenPGP certificates.

373

session = gnutls.connection.ClientSession(self.request,

374

gnutls.connection.\

375

X509Credentials())

452

376

453

377

#priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",

454

378

# "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",

455

379

# "+DHE-DSS"))

456

priority = "NORMAL" # Fallback default, since this

457

# MUST be set.

458

if self.server.settings["priority"]:

459

priority = self.server.settings["priority"]

380

priority = "SECURE256"

381

460

382

gnutls.library.functions.gnutls_priority_set_direct\

461

383

(session._c_object, priority, None);

462

384

463

385

try:

464

386

session.handshake()

465

387

except gnutls.errors.GNUTLSError, error:

466

logger.warning(u"Handshake failed: %s", error)

388

logger.debug(u"Handshake failed: %s", error)

467

389

# Do not run session.bye() here: the session is not

468

390

# established. Just abandon the request.

469

391

return

470

392

try:

471

393

fpr = fingerprint(peer_certificate(session))

472

394

except (TypeError, gnutls.errors.GNUTLSError), error:

473

logger.warning(u"Bad certificate: %s", error)

395

logger.debug(u"Bad certificate: %s", error)

474

396

session.bye()

475

397

return

476

398

logger.debug(u"Fingerprint: %s", fpr)

479

401

if c.fingerprint == fpr:

480

402

client = c

481

403

break

482

if not client:

483

logger.warning(u"Client not found for fingerprint: %s",

484

fpr)

485

session.bye()

486

return

487

404

# Have to check if client.still_valid(), since it is possible

488

405

# that the client timed out while establishing the GnuTLS

489

406

# session.

490

if not client.still_valid():

491

logger.warning(u"Client %(name)s is invalid",

492

vars(client))

407

if (not client) or (not client.still_valid()):

408

if client:

409

logger.debug(u"Client %(name)s is invalid",

410

vars(client))

411

else:

412

logger.debug(u"Client not found for fingerprint: %s",

413

fpr)

493

414

session.bye()

494

415

return

495

416

sent_size = 0

505

426

class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):

506

427

"""IPv6 TCP server. Accepts 'None' as address and/or port.

507

428

Attributes:

508

settings: Server settings

429

options: Command line options

509

430

clients: Set() of Client objects

510

431

"""

511

432

address_family = socket.AF_INET6

512

433

def __init__(self, *args, **kwargs):

513

if "settings" in kwargs:

514

self.settings = kwargs["settings"]

515

del kwargs["settings"]

434

if "options" in kwargs:

435

self.options = kwargs["options"]

436

del kwargs["options"]

516

437

if "clients" in kwargs:

517

438

self.clients = kwargs["clients"]

518

439

del kwargs["clients"]

521

442

"""This overrides the normal server_bind() function

522

443

to bind to an interface if one was specified, and also NOT to

523

444

bind to an address or port if they were not specified."""

524

if self.settings["interface"]:

525

# 25 is from /usr/include/asm-i486/socket.h

526

SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)

445

if self.options.interface:

446

if not hasattr(socket, "SO_BINDTODEVICE"):

447

# From /usr/include/asm-i486/socket.h

448

socket.SO_BINDTODEVICE = 25

527

449

try:

528

450

self.socket.setsockopt(socket.SOL_SOCKET,

529

SO_BINDTODEVICE,

530

self.settings["interface"])

451

socket.SO_BINDTODEVICE,

452

self.options.interface)

531

453

except socket.error, error:

532

454

if error[0] == errno.EPERM:

533

logger.error(u"No permission to"

534

u" bind to interface %s",

535

self.settings["interface"])

455

logger.warning(u"No permission to"

456

u" bind to interface %s",

457

self.options.interface)

536

458

else:

537

459

raise error

538

460

# Only bind(2) the socket if we really need to.

541

463

in6addr_any = "::"

542

464

self.server_address = (in6addr_any,

543

465

self.server_address[1])

544

elif not self.server_address[1]:

466

elif self.server_address[1] is None:

545

467

self.server_address = (self.server_address[0],

546

468

0)

547

# if self.settings["interface"]:

548

# self.server_address = (self.server_address[0],

549

# 0, # port

550

# 0, # flowinfo

551

# if_nametoindex

552

# (self.settings

553

# ["interface"]))

554

469

return super(type(self), self).server_bind()

555

470

556

471

567

482

datetime.timedelta(1)

568

483

>>> string_to_delta(u'1w')

569

484

datetime.timedelta(7)

570

>>> string_to_delta('5m 30s')

571

datetime.timedelta(0, 330)

572

485

"""

573

timevalue = datetime.timedelta(0)

574

for s in interval.split():

575

try:

576

suffix=unicode(s[-1])

577

value=int(s[:-1])

578

if suffix == u"d":

579

delta = datetime.timedelta(value)

580

elif suffix == u"s":

581

delta = datetime.timedelta(0, value)

582

elif suffix == u"m":

583

delta = datetime.timedelta(0, 0, 0, 0, value)

584

elif suffix == u"h":

585

delta = datetime.timedelta(0, 0, 0, 0, 0, value)

586

elif suffix == u"w":

587

delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)

588

else:

589

raise ValueError

590

except (ValueError, IndexError):

486

try:

487

suffix=unicode(interval[-1])

488

value=int(interval[:-1])

489

if suffix == u"d":

490

delta = datetime.timedelta(value)

491

elif suffix == u"s":

492

delta = datetime.timedelta(0, value)

493

elif suffix == u"m":

494

delta = datetime.timedelta(0, 0, 0, 0, value)

495

elif suffix == u"h":

496

delta = datetime.timedelta(0, 0, 0, 0, 0, value)

497

elif suffix == u"w":

498

delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)

499

else:

591

500

raise ValueError

592

timevalue += delta

593

return timevalue

501

except (ValueError, IndexError):

502

raise ValueError

503

return delta

504

505

506

def add_service():

507

"""Derived from the Avahi example code"""

508

global group, serviceName, serviceType, servicePort, serviceTXT, \

509

domain, host

510

if group is None:

511

group = dbus.Interface(

512

bus.get_object( avahi.DBUS_NAME,

513

server.EntryGroupNew()),

514

avahi.DBUS_INTERFACE_ENTRY_GROUP)

515

group.connect_to_signal('StateChanged',

516

entry_group_state_changed)

517

logger.debug(u"Adding service '%s' of type '%s' ...",

518

serviceName, serviceType)

519

520

group.AddService(

521

serviceInterface, # interface

522

avahi.PROTO_INET6, # protocol

523

dbus.UInt32(0), # flags

524

serviceName, serviceType,

525

domain, host,

526

dbus.UInt16(servicePort),

527

avahi.string_array_to_txt_array(serviceTXT))

528

group.Commit()

529

530

531

def remove_service():

532

"""From the Avahi example code"""

533

global group

534

535

if not group is None:

536

group.Reset()

594

537

595

538

596

539

def server_state_changed(state):

597

540

"""Derived from the Avahi example code"""

598

541

if state == avahi.SERVER_COLLISION:

599

logger.error(u"Server name collision")

600

service.remove()

542

logger.warning(u"Server name collision")

543

remove_service()

601

544

elif state == avahi.SERVER_RUNNING:

602

service.add()

545

add_service()

603

546

604

547

605

548

def entry_group_state_changed(state, error):

606

549

"""Derived from the Avahi example code"""

550

global serviceName, server, rename_count

551

607

552

logger.debug(u"state change: %i", state)

608

553

609

554

if state == avahi.ENTRY_GROUP_ESTABLISHED:

610

555

logger.debug(u"Service established.")

611

556

elif state == avahi.ENTRY_GROUP_COLLISION:

612

logger.warning(u"Service name collision.")

613

service.rename()

557

558

rename_count = rename_count - 1

559

if rename_count > 0:

560

name = server.GetAlternativeServiceName(name)

561

logger.warning(u"Service name collision, "

562

u"changing name to '%s' ...", name)

563

remove_service()

564

add_service()

565

566

else:

567

logger.error(u"No suitable service name found after %i"

568

u" retries, exiting.", n_rename)

569

killme(1)

614

570

elif state == avahi.ENTRY_GROUP_FAILURE:

615

logger.critical(u"Error in group state changed %s",

616

unicode(error))

617

raise AvahiGroupError("State changed: %s", str(error))

571

logger.error(u"Error in group state changed %s",

572

unicode(error))

573

killme(1)

574

618

575

619

576

def if_nametoindex(interface):

620

"""Call the C function if_nametoindex(), or equivalent"""

621

global if_nametoindex

577

"""Call the C function if_nametoindex()"""

622

578

try:

623

if "ctypes.util" not in sys.modules:

624

import ctypes.util

625

if_nametoindex = ctypes.cdll.LoadLibrary\

626

(ctypes.util.find_library("c")).if_nametoindex

579

libc = ctypes.cdll.LoadLibrary("libc.so.6")

580

return libc.if_nametoindex(interface)

627

581

except (OSError, AttributeError):

628

582

if "struct" not in sys.modules:

629

583

import struct

630

584

if "fcntl" not in sys.modules:

631

585

import fcntl

632

def if_nametoindex(interface):

633

"Get an interface index the hard way, i.e. using fcntl()"

634

SIOCGIFINDEX = 0x8933 # From /usr/include/linux/sockios.h

635

s = socket.socket()

636

ifreq = fcntl.ioctl(s, SIOCGIFINDEX,

637

struct.pack("16s16x", interface))

638

s.close()

639

interface_index = struct.unpack("I", ifreq[16:20])[0]

640

return interface_index

641

return if_nametoindex(interface)

642

643

644

def daemon(nochdir = False, noclose = False):

586

SIOCGIFINDEX = 0x8933 # From /usr/include/linux/sockios.h

587

s = socket.socket()

588

ifreq = fcntl.ioctl(s, SIOCGIFINDEX,

589

struct.pack("16s16x", interface))

590

s.close()

591

interface_index = struct.unpack("I", ifreq[16:20])[0]

592

return interface_index

593

594

595

def daemon(nochdir, noclose):

645

596

"""See daemon(3). Standard BSD Unix function.

646

597

This should really exist as os.daemon, but it doesn't (yet)."""

647

598

if os.fork():

649

600

os.setsid()

650

601

if not nochdir:

651

602

os.chdir("/")

652

if os.fork():

653

sys.exit()

654

603

if not noclose:

655

604

# Close all standard open file descriptors

656

null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)

605

null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)

657

606

if not stat.S_ISCHR(os.fstat(null).st_mode):

658

607

raise OSError(errno.ENODEV,

659

608

"/dev/null not a character device")

664

613

os.close(null)

665

614

666

615

616

def killme(status = 0):

617

logger.debug("Stopping server with exit status %d", status)

618

exitstatus = status

619

if main_loop_started:

620

main_loop.quit()

621

else:

622

sys.exit(status)

623

624

667

625

def main():

626

global exitstatus

627

exitstatus = 0

668

628

global main_loop_started

669

629

main_loop_started = False

670

630

671

parser = OptionParser(version = "%%prog %s" % version)

631

parser = OptionParser()

672

632

parser.add_option("-i", "--interface", type="string",

673

metavar="IF", help="Bind to interface IF")

674

parser.add_option("-a", "--address", type="string",

633

default=None, metavar="IF",

634

help="Bind to interface IF")

635

parser.add_option("-a", "--address", type="string", default=None,

675

636

help="Address to listen for requests on")

676

parser.add_option("-p", "--port", type="int",

637

parser.add_option("-p", "--port", type="int", default=None,

677

638

help="Port number to receive requests on")

639

parser.add_option("--timeout", type="string", # Parsed later

640

default="1h",

641

help="Amount of downtime allowed for clients")

642

parser.add_option("--interval", type="string", # Parsed later

643

default="5m",

644

help="How often to check that a client is up")

678

645

parser.add_option("--check", action="store_true", default=False,

679

646

help="Run self-test")

680

parser.add_option("--debug", action="store_true",

681

help="Debug mode; run in foreground and log to"

682

" terminal")

683

parser.add_option("--priority", type="string", help="GnuTLS"

684

" priority string (see GnuTLS documentation)")

685

parser.add_option("--servicename", type="string", metavar="NAME",

686

help="Zeroconf service name")

687

parser.add_option("--configdir", type="string",

688

default="/etc/mandos", metavar="DIR",

689

help="Directory to search for configuration"

690

" files")

647

parser.add_option("--debug", action="store_true", default=False,

648

help="Debug mode")

691

649

(options, args) = parser.parse_args()

692

650

693

651

if options.check:

695

653

doctest.testmod()

696

654

sys.exit()

697

655

698

# Default values for config file for server-global settings

699

server_defaults = { "interface": "",

700

"address": "",

701

"port": "",

702

"debug": "False",

703

"priority":

704

"SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",

705

"servicename": "Mandos",

706

}

707

708

# Parse config file for server-global settings

709

server_config = ConfigParser.SafeConfigParser(server_defaults)

710

del server_defaults

711

server_config.read(os.path.join(options.configdir, "mandos.conf"))

712

# Convert the SafeConfigParser object to a dict

713

server_settings = server_config.defaults()

714

# Use getboolean on the boolean config option

715

server_settings["debug"] = server_config.getboolean\

716

("DEFAULT", "debug")

717

del server_config

718

719

# Override the settings from the config file with command line

720

# options, if set.

721

for option in ("interface", "address", "port", "debug",

722

"priority", "servicename", "configdir"):

723

value = getattr(options, option)

724

if value is not None:

725

server_settings[option] = value

726

del options

727

# Now we have our good server settings in "server_settings"

728

729

debug = server_settings["debug"]

730

731

if not debug:

732

syslogger.setLevel(logging.WARNING)

733

console.setLevel(logging.WARNING)

734

735

if server_settings["servicename"] != "Mandos":

736

syslogger.setFormatter(logging.Formatter\

737

('Mandos (%s): %%(levelname)s:'

738

' %%(message)s'

739

% server_settings["servicename"]))

740

741

# Parse config file with clients

742

client_defaults = { "timeout": "1h",

743

"interval": "5m",

744

"checker": "fping -q -- %(host)s",

745

"host": "",

746

}

747

client_config = ConfigParser.SafeConfigParser(client_defaults)

748

client_config.read(os.path.join(server_settings["configdir"],

749

"clients.conf"))

750

751

global service

752

service = AvahiService(name = server_settings["servicename"],

753

type = "_mandos._tcp", );

754

if server_settings["interface"]:

755

service.interface = if_nametoindex(server_settings["interface"])

656

# Parse the time arguments

657

try:

658

options.timeout = string_to_delta(options.timeout)

659

except ValueError:

660

parser.error("option --timeout: Unparseable time")

661

try:

662

options.interval = string_to_delta(options.interval)

663

except ValueError:

664

parser.error("option --interval: Unparseable time")

665

666

# Parse config file

667

defaults = { "checker": "fping -q -- %%(fqdn)s" }

668

client_config = ConfigParser.SafeConfigParser(defaults)

669

#client_config.readfp(open("global.conf"), "global.conf")

670

client_config.read("mandos-clients.conf")

756

671

757

672

global main_loop

758

673

global bus

766

681

avahi.DBUS_INTERFACE_SERVER )

767

682

# End of Avahi example code

768

683

684

debug = options.debug

685

686

if debug:

687

console = logging.StreamHandler()

688

# console.setLevel(logging.DEBUG)

689

console.setFormatter(logging.Formatter\

690

('%(levelname)s: %(message)s'))

691

logger.addHandler(console)

692

del console

693

769

694

clients = Set()

770

695

def remove_from_clients(client):

771

696

clients.remove(client)

772

697

if not clients:

773

logger.critical(u"No clients left, exiting")

774

sys.exit()

698

logger.debug(u"No clients left, exiting")

699

killme()

775

700

776

clients.update(Set(Client(name = section,

701

clients.update(Set(Client(name=section, options=options,

777

702

stop_hook = remove_from_clients,

778

config

779

= dict(client_config.items(section)))

703

**(dict(client_config\

704

.items(section))))

780

705

for section in client_config.sections()))

781

if not clients:

782

logger.critical(u"No clients defined")

783

sys.exit(1)

784

785

if debug:

786

# Redirect stdin so all checkers get /dev/null

787

null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)

788

os.dup2(null, sys.stdin.fileno())

789

if null > 2:

790

os.close(null)

791

else:

792

# No console logging

793

logger.removeHandler(console)

794

# Close all input and output, do double fork, etc.

795

daemon()

796

797

pidfilename = "/var/run/mandos/mandos.pid"

798

pid = os.getpid()

799

try:

800

pidfile = open(pidfilename, "w")

801

pidfile.write(str(pid) + "\n")

802

pidfile.close()

803

del pidfile

804

except IOError, err:

805

logger.error(u"Could not write %s file with PID %d",

806

pidfilename, os.getpid())

706

707

if not debug:

708

daemon(False, False)

807

709

808

710

def cleanup():

809

711

"Cleanup function; run on exit"

823

725

824

726

if not debug:

825

727

signal.signal(signal.SIGINT, signal.SIG_IGN)

826

signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())

827

signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())

728

signal.signal(signal.SIGHUP, lambda signum, frame: killme())

729

signal.signal(signal.SIGTERM, lambda signum, frame: killme())

828

730

829

731

for client in clients:

830

732

client.start()

831

733

832

tcp_server = IPv6_TCPServer((server_settings["address"],

833

server_settings["port"]),

734

tcp_server = IPv6_TCPServer((options.address, options.port),

834

735

tcp_handler,

835

settings=server_settings,

736

options=options,

836

737

clients=clients)

837

# Find out what port we got

838

service.port = tcp_server.socket.getsockname()[1]

839

logger.info(u"Now listening on address %r, port %d, flowinfo %d,"

840

u" scope_id %d" % tcp_server.socket.getsockname())

841

842

#service.interface = tcp_server.socket.getsockname()[3]

843

844

try:

845

# From the Avahi example code

846

server.connect_to_signal("StateChanged", server_state_changed)

847

try:

848

server_state_changed(server.GetState())

849

except dbus.exceptions.DBusException, error:

850

logger.critical(u"DBusException: %s", error)

851

sys.exit(1)

852

# End of Avahi example code

853

854

gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,

855

lambda *args, **kwargs:

856

tcp_server.handle_request\

857

(*args[2:], **kwargs) or True)

858

859

logger.debug(u"Starting main loop")

738

# Find out what random port we got

739

global servicePort

740

servicePort = tcp_server.socket.getsockname()[1]

741

logger.debug(u"Now listening on port %d", servicePort)

742

743

if options.interface is not None:

744

global serviceInterface

745

serviceInterface = if_nametoindex(options.interface)

746

747

# From the Avahi example code

748

server.connect_to_signal("StateChanged", server_state_changed)

749

try:

750

server_state_changed(server.GetState())

751

except dbus.exceptions.DBusException, error:

752

logger.critical(u"DBusException: %s", error)

753

killme(1)

754

# End of Avahi example code

755

756

gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,

757

lambda *args, **kwargs:

758

tcp_server.handle_request(*args[2:],

759

**kwargs) or True)

760

try:

761

logger.debug("Starting main loop")

860

762

main_loop_started = True

861

763

main_loop.run()

862

except AvahiError, error:

863

logger.critical(u"AvahiError: %s" + unicode(error))

864

sys.exit(1)

865

764

except KeyboardInterrupt:

866

765

if debug:

867

766

print

767

768

sys.exit(exitstatus)

868

769

869

770

if __name__ == '__main__':

870

771

main()