## auth.py
##
## Copyright (C) 2003-2005 Alexey "Snake" Nezhdanov
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2, or (at your option)
## any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU General Public License for more details.
# $Id: auth.py,v 1.37 2006/08/21 08:11:51 normanr Exp $
"""
Provides library with all Non-SASL and SASL authentication mechanisms.
Can be used both for client and transport authentication.
"""
from protocol import *
from client import PlugIn
import sha,base64,random,dispatcher,re
import md5
def HH(some): return md5.new(some).hexdigest()
def H(some): return md5.new(some).digest()
def C(some): return ':'.join(some)
class NonSASL(PlugIn):
""" Implements old Non-SASL (JEP-0078) authentication used in jabberd1.4 and transport authentication."""
def __init__(self,user,password,resource):
""" Caches username, password and resource for auth. """
PlugIn.__init__(self)
self.DBG_LINE='gen_auth'
self.user=user
self.password=password
self.resource=resource
def plugin(self,owner):
""" Determine the best auth method (digest/0k/plain) and use it for auth.
Returns used method name on success. Used internally. """
if not self.resource: return self.authComponent(owner)
self.DEBUG('Querying server about possible auth methods','start')
resp=owner.Dispatcher.SendAndWaitForResponse(Iq('get',NS_AUTH,payload=[Node('username',payload=[self.user])]))
if not isResultNode(resp):
self.DEBUG('No result node arrived! Aborting...','error')
return
iq=Iq(typ='set',node=resp)
query=iq.getTag('query')
query.setTagData('username',self.user)
query.setTagData('resource',self.resource)
if query.getTag('digest'):
self.DEBUG("Performing digest authentication",'ok')
query.setTagData('digest',sha.new(owner.Dispatcher.Stream._document_attrs['id']+self.password).hexdigest())
if query.getTag('password'): query.delChild('password')
method='digest'
elif query.getTag('token'):
token=query.getTagData('token')
seq=query.getTagData('sequence')
self.DEBUG("Performing zero-k authentication",'ok')
hash = sha.new(sha.new(self.password).hexdigest()+token).hexdigest()
for foo in xrange(int(seq)): hash = sha.new(hash).hexdigest()
query.setTagData('hash',hash)
method='0k'
else:
self.DEBUG("Sequre methods unsupported, performing plain text authentication",'warn')
query.setTagData('password',self.password)
method='plain'
resp=owner.Dispatcher.SendAndWaitForResponse(iq)
if isResultNode(resp):
self.DEBUG('Sucessfully authenticated with remove host.','ok')
owner.User=self.user
owner.Resource=self.resource
owner._registered_name=owner.User+'@'+owner.Server+'/'+owner.Resource
return method
self.DEBUG('Authentication failed!','error')
def authComponent(self,owner):
""" Authenticate component. Send handshake stanza and wait for result. Returns "ok" on success. """
self.handshake=0
owner.send(Node(NS_COMPONENT_ACCEPT+' handshake',payload=[sha.new(owner.Dispatcher.Stream._document_attrs['id']+self.password).hexdigest()]))
owner.RegisterHandler('handshake',self.handshakeHandler,xmlns=NS_COMPONENT_ACCEPT)
while not self.handshake:
self.DEBUG("waiting on handshake",'notify')
owner.Process(1)
owner._registered_name=self.user
if self.handshake+1: return 'ok'
def handshakeHandler(self,disp,stanza):
""" Handler for registering in dispatcher for accepting transport authentication. """
if stanza.getName()=='handshake': self.handshake=1
else: self.handshake=-1
class SASL(PlugIn):
""" Implements SASL authentication. """
def __init__(self,username,password):
PlugIn.__init__(self)
self.username=username
self.password=password
def plugin(self,owner):
if not self._owner.Dispatcher.Stream._document_attrs.has_key('version'): self.startsasl='not-supported'
elif self._owner.Dispatcher.Stream.features:
try: self.FeaturesHandler(self._owner.Dispatcher,self._owner.Dispatcher.Stream.features)
except NodeProcessed: pass
else: self.startsasl=None
def auth(self):
""" Start authentication. Result can be obtained via "SASL.startsasl" attribute and will be
either "success" or "failure". Note that successfull auth will take at least
two Dispatcher.Process() calls. """
if self.startsasl: pass
elif self._owner.Dispatcher.Stream.features:
try: self.FeaturesHandler(self._owner.Dispatcher,self._owner.Dispatcher.Stream.features)
except NodeProcessed: pass
else: self._owner.RegisterHandler('features',self.FeaturesHandler,xmlns=NS_STREAMS)
def plugout(self):
""" Remove SASL handlers from owner's dispatcher. Used internally. """
self._owner.UnregisterHandler('features',self.FeaturesHandler,xmlns=NS_STREAMS)
self._owner.UnregisterHandler('challenge',self.SASLHandler,xmlns=NS_SASL)
self._owner.UnregisterHandler('failure',self.SASLHandler,xmlns=NS_SASL)
self._owner.UnregisterHandler('success',self.SASLHandler,xmlns=NS_SASL)
def FeaturesHandler(self,conn,feats):
""" Used to determine if server supports SASL auth. Used internally. """
if not feats.getTag('mechanisms',namespace=NS_SASL):
self.startsasl='not-supported'
self.DEBUG('SASL not supported by server','error')
return
mecs=[]
for mec in feats.getTag('mechanisms',namespace=NS_SASL).getTags('mechanism'):
mecs.append(mec.getData())
self._owner.RegisterHandler('challenge',self.SASLHandler,xmlns=NS_SASL)
self._owner.RegisterHandler('failure',self.SASLHandler,xmlns=NS_SASL)
self._owner.RegisterHandler('success',self.SASLHandler,xmlns=NS_SASL)
if "DIGEST-MD5" in mecs:
node=Node('auth',attrs={'xmlns':NS_SASL,'mechanism':'DIGEST-MD5'})
elif "PLAIN" in mecs:
sasl_data='%s\x00%s\x00%s'%(self.username+'@'+self._owner.Server,self.username,self.password)
node=Node('auth',attrs={'xmlns':NS_SASL,'mechanism':'PLAIN'},payload=[base64.encodestring(sasl_data)])
else:
self.startsasl='failure'
self.DEBUG('I can only use DIGEST-MD5 and PLAIN mecanisms.','error')
return
self.startsasl='in-process'
self._owner.send(node.__str__())
raise NodeProcessed
def SASLHandler(self,conn,challenge):
""" Perform next SASL auth step. Used internally. """
if challenge.getNamespace()<>NS_SASL: return
if challenge.getName()=='failure':
self.startsasl='failure'
try: reason=challenge.getChildren()[0]
except: reason=challenge
self.DEBUG('Failed SASL authentification: %s'%reason,'error')
raise NodeProcessed
elif challenge.getName()=='success':
self.startsasl='success'
self.DEBUG('Successfully authenticated with remote server.','ok')
handlers=self._owner.Dispatcher.dumpHandlers()
self._owner.Dispatcher.PlugOut()
dispatcher.Dispatcher().PlugIn(self._owner)
self._owner.Dispatcher.restoreHandlers(handlers)
self._owner.User=self.username
raise NodeProcessed
########################################3333
incoming_data=challenge.getData()
chal={}
data=base64.decodestring(incoming_data)
self.DEBUG('Got challenge:'+data,'ok')
for pair in re.findall('(\w+=(?:"[^"]+")|(?:[^,]+))',data):
key,value=pair.split('=', 1)
if value[:1]=='"' and value[-1:]=='"': value=value[1:-1]
chal[key]=value
if chal.has_key('qop') and 'auth' in chal['qop'].split(','):
resp={}
resp['username']=self.username
resp['realm']=self._owner.Server
resp['nonce']=chal['nonce']
cnonce=''
for i in range(7):
cnonce+=hex(int(random.random()*65536*4096))[2:]
resp['cnonce']=cnonce
resp['nc']=('00000001')
resp['qop']='auth'
resp['digest-uri']='xmpp/'+self._owner.Server
A1=C([H(C([resp['username'],resp['realm'],self.password])),resp['nonce'],resp['cnonce']])
A2=C(['AUTHENTICATE',resp['digest-uri']])
response= HH(C([HH(A1),resp['nonce'],resp['nc'],resp['cnonce'],resp['qop'],HH(A2)]))
resp['response']=response
resp['charset']='utf-8'
sasl_data=''
for key in ['charset','username','realm','nonce','nc','cnonce','digest-uri','response','qop']:
if key in ['nc','qop','response','charset']: sasl_data+="%s=%s,"%(key,resp[key])
else: sasl_data+='%s="%s",'%(key,resp[key])
########################################3333
node=Node('response',attrs={'xmlns':NS_SASL},payload=[base64.encodestring(sasl_data[:-1]).replace('\r','').replace('\n','')])
self._owner.send(node.__str__())
elif chal.has_key('rspauth'): self._owner.send(Node('response',attrs={'xmlns':NS_SASL}).__str__())
else:
self.startsasl='failure'
self.DEBUG('Failed SASL authentification: unknown challenge','error')
raise NodeProcessed
class Bind(PlugIn):
""" Bind some JID to the current connection to allow router know of our location."""
def __init__(self):
PlugIn.__init__(self)
self.DBG_LINE='bind'
self.bound=None
def plugin(self,owner):
""" Start resource binding, if allowed at this time. Used internally. """
if self._owner.Dispatcher.Stream.features:
try: self.FeaturesHandler(self._owner.Dispatcher,self._owner.Dispatcher.Stream.features)
except NodeProcessed: pass
else: self._owner.RegisterHandler('features',self.FeaturesHandler,xmlns=NS_STREAMS)
def plugout(self):
""" Remove Bind handler from owner's dispatcher. Used internally. """
self._owner.UnregisterHandler('features',self.FeaturesHandler,xmlns=NS_STREAMS)
def FeaturesHandler(self,conn,feats):
""" Determine if server supports resource binding and set some internal attributes accordingly. """
if not feats.getTag('bind',namespace=NS_BIND):
self.bound='failure'
self.DEBUG('Server does not requested binding.','error')
return
if feats.getTag('session',namespace=NS_SESSION): self.session=1
else: self.session=-1
self.bound=[]
def Bind(self,resource=None):
""" Perform binding. Use provided resource name or random (if not provided). """
while self.bound is None and self._owner.Process(1): pass
if resource: resource=[Node('resource',payload=[resource])]
else: resource=[]
resp=self._owner.SendAndWaitForResponse(Protocol('iq',typ='set',payload=[Node('bind',attrs={'xmlns':NS_BIND},payload=resource)]))
if isResultNode(resp):
self.bound.append(resp.getTag('bind').getTagData('jid'))
self.DEBUG('Successfully bound %s.'%self.bound[-1],'ok')
jid=JID(resp.getTag('bind').getTagData('jid'))
self._owner.User=jid.getNode()
self._owner.Resource=jid.getResource()
resp=self._owner.SendAndWaitForResponse(Protocol('iq',typ='set',payload=[Node('session',attrs={'xmlns':NS_SESSION})]))
if isResultNode(resp):
self.DEBUG('Successfully opened session.','ok')
self.session=1
return 'ok'
else:
self.DEBUG('Session open failed.','error')
self.session=0
elif resp: self.DEBUG('Binding failed: %s.'%resp.getTag('error'),'error')
else:
self.DEBUG('Binding failed: timeout expired.','error')
return ''
class ComponentBind(PlugIn):
""" ComponentBind some JID to the current connection to allow router know of our location."""
def __init__(self, sasl):
PlugIn.__init__(self)
self.DBG_LINE='bind'
self.bound=None
self.needsUnregister=None
self.sasl = sasl
def plugin(self,owner):
""" Start resource binding, if allowed at this time. Used internally. """
if not self.sasl:
self.bound=[]
return
if self._owner.Dispatcher.Stream.features:
try: self.FeaturesHandler(self._owner.Dispatcher,self._owner.Dispatcher.Stream.features)
except NodeProcessed: pass
else:
self._owner.RegisterHandler('features',self.FeaturesHandler,xmlns=NS_STREAMS)
self.needsUnregister=1
def plugout(self):
""" Remove ComponentBind handler from owner's dispatcher. Used internally. """
if self.needsUnregister:
self._owner.UnregisterHandler('features',self.FeaturesHandler,xmlns=NS_STREAMS)
def FeaturesHandler(self,conn,feats):
""" Determine if server supports resource binding and set some internal attributes accordingly. """
if not feats.getTag('bind',namespace=NS_BIND):
self.bound='failure'
self.DEBUG('Server does not requested binding.','error')
return
if feats.getTag('session',namespace=NS_SESSION): self.session=1
else: self.session=-1
self.bound=[]
def Bind(self,domain=None):
""" Perform binding. Use provided domain name (if not provided). """
while self.bound is None and self._owner.Process(1): pass
if self.sasl:
xmlns = NS_COMPONENT_1
else:
xmlns = None
self.bindresponse = None
ttl = dispatcher.DefaultTimeout
self._owner.RegisterHandler('bind',self.BindHandler,xmlns=xmlns)
self._owner.send(Protocol('bind',attrs={'name':domain},xmlns=NS_COMPONENT_1))
while self.bindresponse is None and self._owner.Process(1) and ttl > 0: ttl-=1
self._owner.UnregisterHandler('bind',self.BindHandler,xmlns=xmlns)
resp=self.bindresponse
if resp and resp.getAttr('error'):
self.DEBUG('Binding failed: %s.'%resp.getAttr('error'),'error')
elif resp:
self.DEBUG('Successfully bound.','ok')
return 'ok'
else:
self.DEBUG('Binding failed: timeout expired.','error')
return ''
def BindHandler(self,conn,bind):
self.bindresponse = bind
pass