def check_and_demangle_item(item):
"""Return demangled item if it is a valid mangled item,
otherwise throw an exception (not necessarily of class error.Error).
Ensures: either an exception is thrown or ret is a dictionary
whose keys include 'type'."""
# note: not sure if this ough to be here...
import crypto.RSA
import hash
import safe_pickle
item_type = item['type']
if item_type == 'identity offline demangled':
raise error.Error('impostor')
elif item_type == 'identity offline':
demangle = safe_pickle.loads(item['package'])
if not crypto.RSA.construct(demangle['key']).verify(
hash.hash_of(item['package']),item['signature']):
raise error.Error('bad signature')
demangle['type'] = 'identity offline demangled'
return demangle
else:
return item
def decrypt(self, crypt):
# Todo: catch errors
self.lock.acquire()
try:
encrypted_key, encrypted_text = crypt
key = self.key.decrypt((encrypted_key,))
while len(key) < 16:
key = chr(0)+key
decryptor = crypto.rijndael.rijndael(key, 16)
text = decryptor.decrypt_cbc(encrypted_text)
return safe_pickle.loads(text)
finally:
self.lock.release()
def handle(self, request, address,call_id):
check.check_matches(request, (types.StringType,)) #=@R34
check.check_is_af_inet_address(address) #=@R31
self.lock.acquire()
try:
if request[0] == 'chat look':
return (not self.quiet, self.activity)
if request[0] in ['chat message 2']:
unpacked = safe_pickle.loads(request[1])
# TODO check unpacked against template
# TODO don't unpack twice (here and in receive task)
sender = unpacked['from']
recipients = unpacked['to']
for recipient in recipients:
if recipient[0] == self.app.name_server.public_key_name:
break
if recipient[2][:1] == '#' and \
self.channels.is_listening_to(recipient[2]) and \
sender[0] != self.app.name_server.public_key_name:
break
else:
return None
if not self.repeated(address,call_id):
if self.quiet:
new_item = (request, address, time.time())
check.check_matches(new_item,
unread_message_list_item_tmpl)
# Proof: @R34,@R31, and not having modified request or
# address, and the relevant types being immutable
# (partly by @E11). time.time() returns float.
# Relevance: @R.I15.
self.unread_message_list.append(new_item)
self.set_prompt()
del new_item
else:
self.receive(request,address,self.quiet,time.time())
# Proof of @R33: @R31; deep immutability by @E11.
# Proof of @R35: time.time() returns float.
return (not self.quiet, self.activity)
finally:
self.lock.release()
def receive(self, request, address, quiet, send_time, add_to_history=1):
"""send_time should be as if from time.time() (i.e. a float expressing seconds
since the local machine's epoch) rather than the standardized timestamps
sent over the network (i.e. a long expressing seconds since the Unix epoch
of 1970)."""
# TODO: more checking of message format
# TODO: search for people not in acq list
check.check_is_opt_address(address) #=@R33 fixme callers
check.check_has_type(send_time, types.FloatType) #=@R35 fixme callers
# fixme: should probably require that request be a tuple with 5+ elems.
if 1:
if not self.is_visible():
self.n_unseen_messages = self.n_unseen_messages + 1
if self.n_unseen_messages == 1:
title = _('1 unseen message')
else:
title = _('%d unseen messages') % self.n_unseen_messages
self.app.set_title(title)
if request[0] == 'chat message 2':
package = safe_pickle.loads(request[1])
text = package['text']
augmentation = package.get('aug')
has_attachment = package.has_key('attach')
attachment = package.get('attach')
sender_key_name, sender_name = package['from']
recipients = package['to']
verify_text = request[1]
verify_sig = request[2]
else:
# Legacy message format
text = request[3]
augmentation = None
has_attachment = (len(request) == 6)
if has_attachment:
attachment = safe_pickle.loads(request[4])
recipients = request[2]
if type(request[1]) == type(()):
sender_key_name = request[1][0]
sender_name = request[1][1]
else:
# Used not to send username with key name
sender_key_name = request[1]
sender_name = 'unknown'
if has_attachment:
verify_text = request[3].encode('utf8')+request[4]
verify_sig = request[5]
else:
verify_text = request[3]
verify_sig = request[4]
if not augmentation:
augmentation = chr(128) * len(text)
self.show_received_message(sender_name,sender_key_name,address,recipients,
text,verify_text,verify_sig,quiet,
send_time,augmentation,has_attachment,attachment)
#except error.Error:
# self.show(_('Bad message received from ') + repr(address) + '\n')
if add_to_history:
self.lock.acquire()
try:
new_item = (request, send_time)
check.check_matches(new_item, incoming_message_history_item_tmpl)
# Proof: @R35, immutability of float, send_time not reassigned
# in this function.
# Relevance: @I16.
self.incoming_message_history.append(new_item)
while len(self.incoming_message_history) > settings.incoming_message_history_size:
del self.incoming_message_history[0]
finally:
self.lock.release()
def gossip_fetch_thread(self,acq):
self.fetch_threads+=1
if not self.running:
self.fetch_threads-=1
return
if acq.distance != None:
#acq.start_watching(self.node, 1)
acq.lock.acquire()
online = acq.online
address = acq.address
distance = acq.distance
acq.lock.release()
if distance == None or not online:
self.fetch_threads-=1
return
pos = 0
fetch_timeout = node.make_timeout(settings.gossip_fetch_time)
while not node.is_timed_out(fetch_timeout):
try:
ticket, template, wait = self.node.call(address,('gossip list',pos,pos+20))
if wait: yield 'call',(self.node,ticket)
result = self.node.get_reply(ticket,template)
if not check.matches(result,
[(types.IntType, 'any', 'any')]):
node.bad_peer(address,
_("Bad reply to 'gossip list': ") + `result`)
break
if len(result) == 0:
break
all_ok = 1
# effic: sort self.gossip, sort the returned results,
# to speed up searches for signatures. However, I
# haven't yet seen gossip_fetch_task come up in
# profiles.
for item in result:
already_there = 0
for wodge in self.gossip:
if wodge.signature == item[2]:
#if wodge.distance(self.app.name_server) > from_fixed(item[0])+distance:
# # TODO: What to do with unit_decay_time?
# wodge.initial_distance = from_fixed(item[0])+distance
# wodge.initial_time = time.time()
wodge.opinions[acq.name] = from_fixed(item[0]) - wodge.decay()
already_there = 1
break
if already_there:
continue
try:
ticket, template, wait = self.node.call(
address,('gossip get',item[2]))
if wait: yield 'call',(self.node,ticket)
string = self.node.get_reply(ticket, template)
wodgewodge = safe_pickle.loads(string)
except error.Error:
all_ok = 0
break
#TODO: Confirm signature of known people
wodge = Wodge({
'wodge': wodgewodge,
'string': string,
'signature': item[2],
'initial_time': time.time(),
'initial_distance': None,
#'initial_distance': from_fixed(item[0]) + distance
'unit_decay_time': item[1],
'opinions': { acq.name : from_fixed(item[0]) },
'collapsed': 0})
if not self.insert_wodge(wodge):
all_ok = 0
break
if not all_ok:
break
pos = pos + 18
except error.Error:
break
self.fetch_threads-=1
