/mandos/trunk : revision 18

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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

237

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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247

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):

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

312

252

If a checker already exists, leave it running and do

321

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# is as it should be.

322

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if self.checker is None:

323

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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

266

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

329

267

for key, val in

330

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vars(self).iteritems())

331

269

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

274

return True # Try again later

337

275

try:

338

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

339

command, self.name)

340

self.checker = subprocess.Popen(command,

341

close_fds=True,

342

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="/")

343

282

self.checker_callback_tag = gobject.child_watch_add\

344

283

(self.checker.pid,

345

284

self.checker_callback)

353

292

if self.checker_callback_tag:

354

293

gobject.source_remove(self.checker_callback_tag)

355

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self.checker_callback_tag = None

356

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

295

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

357

296

return

358

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

297

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

359

298

try:

360

299

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

361

300

#os.sleep(0.5)

362

301

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

363

302

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

364

303

except OSError, error:

365

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

304

if error.errno != errno.ESRCH:

366

305

raise

367

306

self.checker = None

368

def still_valid(self):

307

def still_valid(self, now=None):

369

308

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

370

now = datetime.datetime.now()

371

if self.last_checked_ok is None:

309

if now is None:

310

now = datetime.datetime.now()

311

if self.last_seen is None:

372

312

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

373

313

else:

374

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

314

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

375

315

376

316

377

317

def peer_certificate(session):

393

333

394

334

def fingerprint(openpgp):

395

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))

396

340

# New GnuTLS "datum" with the OpenPGP public key

397

341

datum = gnutls.library.types.gnutls_datum_t\

398

342

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

399

343

ctypes.POINTER(ctypes.c_ubyte)),

400

344

ctypes.c_uint(len(openpgp)))

401

# New empty GnuTLS certificate

402

crt = gnutls.library.types.gnutls_openpgp_crt_t()

403

gnutls.library.functions.gnutls_openpgp_crt_init\

404

(ctypes.byref(crt))

405

345

# Import the OpenPGP public key into the certificate

406

gnutls.library.functions.gnutls_openpgp_crt_import\

407

(crt, ctypes.byref(datum),

408

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)

409

350

# New buffer for the fingerprint

410

351

buffer = ctypes.create_string_buffer(20)

411

352

buffer_length = ctypes.c_size_t()

427

368

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

428

369

429

370

def handle(self):

430

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

371

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

431

372

unicode(self.client_address))

432

session = gnutls.connection.ClientSession\

433

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

434

435

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

436

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

437

try:

438

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

439

raise RuntimeError

440

except (ValueError, IndexError, RuntimeError), error:

441

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

442

return

443

444

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

445

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

446

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

447

# using OpenPGP certificates.

373

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

374

gnutls.connection.\

375

X509Credentials())

448

376

449

377

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

450

378

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

451

379

# "+DHE-DSS"))

452

priority = "NORMAL" # Fallback default, since this

453

# MUST be set.

454

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

455

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

380

priority = "SECURE256"

381

456

382

gnutls.library.functions.gnutls_priority_set_direct\

457

383

(session._c_object, priority, None);

458

384

459

385

try:

460

386

session.handshake()

461

387

except gnutls.errors.GNUTLSError, error:

462

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

388

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

463

389

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

464

390

# established. Just abandon the request.

465

391

return

466

392

try:

467

393

fpr = fingerprint(peer_certificate(session))

468

394

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

469

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

395

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

470

396

session.bye()

471

397

return

472

398

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

475

401

if c.fingerprint == fpr:

476

402

client = c

477

403

break

478

if not client:

479

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

480

fpr)

481

session.bye()

482

return

483

404

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

484

405

# that the client timed out while establishing the GnuTLS

485

406

# session.

486

if not client.still_valid():

487

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

488

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)

489

414

session.bye()

490

415

return

491

416

sent_size = 0

501

426

class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):

502

427

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

503

428

Attributes:

504

settings: Server settings

429

options: Command line options

505

430

clients: Set() of Client objects

506

431

"""

507

432

address_family = socket.AF_INET6

508

433

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

509

if "settings" in kwargs:

510

self.settings = kwargs["settings"]

511

del kwargs["settings"]

434

if "options" in kwargs:

435

self.options = kwargs["options"]

436

del kwargs["options"]

512

437

if "clients" in kwargs:

513

438

self.clients = kwargs["clients"]

514

439

del kwargs["clients"]

517

442

"""This overrides the normal server_bind() function

518

443

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

519

444

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

520

if self.settings["interface"]:

521

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

522

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

523

449

try:

524

450

self.socket.setsockopt(socket.SOL_SOCKET,

525

SO_BINDTODEVICE,

526

self.settings["interface"])

451

socket.SO_BINDTODEVICE,

452

self.options.interface)

527

453

except socket.error, error:

528

454

if error[0] == errno.EPERM:

529

logger.error(u"No permission to"

530

u" bind to interface %s",

531

self.settings["interface"])

455

logger.warning(u"No permission to"

456

u" bind to interface %s",

457

self.options.interface)

532

458

else:

533

459

raise error

534

460

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

537

463

in6addr_any = "::"

538

464

self.server_address = (in6addr_any,

539

465

self.server_address[1])

540

elif not self.server_address[1]:

466

elif self.server_address[1] is None:

541

467

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

542

468

0)

543

# if self.settings["interface"]:

544

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

545

# 0, # port

546

# 0, # flowinfo

547

# if_nametoindex

548

# (self.settings

549

# ["interface"]))

550

469

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

551

470

552

471

584

503

return delta

585

504

586

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()

537

538

587

539

def server_state_changed(state):

588

540

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

589

541

if state == avahi.SERVER_COLLISION:

590

logger.error(u"Server name collision")

591

service.remove()

542

logger.warning(u"Server name collision")

543

remove_service()

592

544

elif state == avahi.SERVER_RUNNING:

593

service.add()

545

add_service()

594

546

595

547

596

548

def entry_group_state_changed(state, error):

597

549

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

550

global serviceName, server, rename_count

551

598

552

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

599

553

600

554

if state == avahi.ENTRY_GROUP_ESTABLISHED:

601

555

logger.debug(u"Service established.")

602

556

elif state == avahi.ENTRY_GROUP_COLLISION:

603

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

604

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)

605

570

elif state == avahi.ENTRY_GROUP_FAILURE:

606

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

607

unicode(error))

608

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

571

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

572

unicode(error))

573

killme(1)

574

609

575

610

576

def if_nametoindex(interface):

611

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

612

global if_nametoindex

577

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

613

578

try:

614

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

615

import ctypes.util

616

if_nametoindex = ctypes.cdll.LoadLibrary\

617

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

579

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

580

return libc.if_nametoindex(interface)

618

581

except (OSError, AttributeError):

619

582

if "struct" not in sys.modules:

620

583

import struct

621

584

if "fcntl" not in sys.modules:

622

585

import fcntl

623

def if_nametoindex(interface):

624

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

625

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

626

s = socket.socket()

627

ifreq = fcntl.ioctl(s, SIOCGIFINDEX,

628

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

629

s.close()

630

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

631

return interface_index

632

return if_nametoindex(interface)

633

634

635

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):

636

596

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

637

597

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

638

598

if os.fork():

640

600

os.setsid()

641

601

if not nochdir:

642

602

os.chdir("/")

643

if os.fork():

644

sys.exit()

645

603

if not noclose:

646

604

# Close all standard open file descriptors

647

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

605

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

648

606

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

649

607

raise OSError(errno.ENODEV,

650

608

"/dev/null not a character device")

655

613

os.close(null)

656

614

657

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

658

625

def main():

626

global exitstatus

627

exitstatus = 0

659

628

global main_loop_started

660

629

main_loop_started = False

661

630

662

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

631

parser = OptionParser()

663

632

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

664

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

665

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,

666

636

help="Address to listen for requests on")

667

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

637

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

668

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")

669

645

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

670

646

help="Run self-test")

671

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

672

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

673

" terminal")

674

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

675

" priority string (see GnuTLS documentation)")

676

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

677

help="Zeroconf service name")

678

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

679

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

680

help="Directory to search for configuration"

681

" files")

647

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

648

help="Debug mode")

682

649

(options, args) = parser.parse_args()

683

650

684

651

if options.check:

686

653

doctest.testmod()

687

654

sys.exit()

688

655

689

# Default values for config file for server-global settings

690

server_defaults = { "interface": "",

691

"address": "",

692

"port": "",

693

"debug": "False",

694

"priority":

695

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

696

"servicename": "Mandos",

697

}

698

699

# Parse config file for server-global settings

700

server_config = ConfigParser.SafeConfigParser(server_defaults)

701

del server_defaults

702

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

703

# Convert the SafeConfigParser object to a dict

704

server_settings = server_config.defaults()

705

# Use getboolean on the boolean config option

706

server_settings["debug"] = server_config.getboolean\

707

("DEFAULT", "debug")

708

del server_config

709

710

# Override the settings from the config file with command line

711

# options, if set.

712

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

713

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

714

value = getattr(options, option)

715

if value is not None:

716

server_settings[option] = value

717

del options

718

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

719

720

debug = server_settings["debug"]

721

722

if not debug:

723

syslogger.setLevel(logging.WARNING)

724

console.setLevel(logging.WARNING)

725

726

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

727

syslogger.setFormatter(logging.Formatter\

728

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

729

' %%(message)s'

730

% server_settings["servicename"]))

731

732

# Parse config file with clients

733

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

734

"interval": "5m",

735

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

736

}

737

client_config = ConfigParser.SafeConfigParser(client_defaults)

738

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

739

"clients.conf"))

740

741

global service

742

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

743

type = "_mandos._tcp", );

744

if server_settings["interface"]:

745

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")

746

671

747

672

global main_loop

748

673

global bus

756

681

avahi.DBUS_INTERFACE_SERVER )

757

682

# End of Avahi example code

758

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

759

694

clients = Set()

760

695

def remove_from_clients(client):

761

696

clients.remove(client)

762

697

if not clients:

763

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

764

sys.exit()

698

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

699

killme()

765

700

766

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

701

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

767

702

stop_hook = remove_from_clients,

768

config

769

= dict(client_config.items(section)))

703

**(dict(client_config\

704

.items(section))))

770

705

for section in client_config.sections()))

771

if not clients:

772

logger.critical(u"No clients defined")

773

sys.exit(1)

774

706

775

707

if not debug:

776

logger.removeHandler(console)

777

daemon()

778

779

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

780

pid = os.getpid()

781

try:

782

pidfile = open(pidfilename, "w")

783

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

784

pidfile.close()

785

del pidfile

786

except IOError, err:

787

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

788

pidfilename, os.getpid())

708

daemon(False, False)

789

709

790

710

def cleanup():

791

711

"Cleanup function; run on exit"

805

725

806

726

if not debug:

807

727

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

808

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

809

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())

810

730

811

731

for client in clients:

812

732

client.start()

813

733

814

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

815

server_settings["port"]),

734

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

816

735

tcp_handler,

817

settings=server_settings,

736

options=options,

818

737

clients=clients)

819

# Find out what port we got

820

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

821

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

822

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

823

824

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

825

826

try:

827

# From the Avahi example code

828

server.connect_to_signal("StateChanged", server_state_changed)

829

try:

830

server_state_changed(server.GetState())

831

except dbus.exceptions.DBusException, error:

832

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

833

sys.exit(1)

834

# End of Avahi example code

835

836

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

837

lambda *args, **kwargs:

838

tcp_server.handle_request\

839

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

840

841

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")

842

762

main_loop_started = True

843

763

main_loop.run()

844

except AvahiError, error:

845

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

846

sys.exit(1)

847

764

except KeyboardInterrupt:

848

765

if debug:

849

766

print

767

768

sys.exit(exitstatus)

850

769

851

770

if __name__ == '__main__':

852

771

main()