src/class_outgoingSynSender.py

@@ -22,26 +22,37 @@ class outgoingSynSender(threading.Thread):
         self.streamNumber = streamNumber
         self.selfInitiatedConnections = selfInitiatedConnections
 
+    def _getPeer(self):
+        # If the user has specified a trusted peer then we'll only
+        # ever connect to that. Otherwise we'll pick a random one from
+        # the known nodes
+        shared.knownNodesLock.acquire()
+        if shared.trustedPeer:
+            peer = shared.trustedPeer
+            shared.knownNodes[self.streamNumber][peer] = time.time()
+        else:
+            peer, = random.sample(shared.knownNodes[self.streamNumber], 1)
+        shared.knownNodesLock.release()
+
+        return peer
+
     def run(self):
         while shared.safeConfigGetBoolean('bitmessagesettings', 'dontconnect'):
             time.sleep(2)
         while shared.safeConfigGetBoolean('bitmessagesettings', 'sendoutgoingconnections'):
-            while len(self.selfInitiatedConnections[self.streamNumber]) >= 8:  # maximum number of outgoing connections = 8
+            maximumConnections = 1 if shared.trustedPeer else 8 # maximum number of outgoing connections = 8
+            while len(self.selfInitiatedConnections[self.streamNumber]) >= maximumConnections:
                 time.sleep(10)
             if shared.shutdown:
                 break
             random.seed()
-            shared.knownNodesLock.acquire()
+            peer = self._getPeer()
-            peer, = random.sample(shared.knownNodes[self.streamNumber], 1)
-            shared.knownNodesLock.release()
             shared.alreadyAttemptedConnectionsListLock.acquire()
             while peer in shared.alreadyAttemptedConnectionsList or peer.host in shared.connectedHostsList:
                 shared.alreadyAttemptedConnectionsListLock.release()
                 # print 'choosing new sample'
                 random.seed()
-                shared.knownNodesLock.acquire()
+                peer = self._getPeer()
-                peer, = random.sample(shared.knownNodes[self.streamNumber], 1)
-                shared.knownNodesLock.release()
                 time.sleep(1)
                 # Clear out the shared.alreadyAttemptedConnectionsList every half
                 # hour so that this program will again attempt a connection

src/class_receiveDataThread.py

@@ -313,6 +313,14 @@ class receiveDataThread(threading.Thread):
             print 'Sending huge inv message with', numberOfObjects, 'objects to just this one peer'
         self.sendDataThreadQueue.put((0, 'sendRawData', headerData + payload))
 
+    def _sleepForTimingAttackMitigation(self, sleepTime):
+        # We don't need to do the timing attack mitigation if we are
+        # only connected to the trusted peer because we can trust the
+        # peer not to attack
+        if sleepTime > 0 and doTimingAttackMitigation and shared.trustedPeer == None:
+            with shared.printLock:
+                print 'Timing attack mitigation: Sleeping for', sleepTime, 'seconds.'
+            time.sleep(sleepTime)
 
     # We have received a broadcast message
     def recbroadcast(self, data):
@@ -341,10 +349,7 @@ class receiveDataThread(threading.Thread):
 
         sleepTime = lengthOfTimeWeShouldUseToProcessThisMessage - \
             (time.time() - self.messageProcessingStartTime)
-        if sleepTime > 0 and doTimingAttackMitigation:
+        self._sleepForTimingAttackMitigation(sleepTime)
-            with shared.printLock:
-                print 'Timing attack mitigation: Sleeping for', sleepTime, 'seconds.'
-            time.sleep(sleepTime)
 
     # We have received a msg message.
     def recmsg(self, data):
@@ -373,10 +378,7 @@ class receiveDataThread(threading.Thread):
 
         sleepTime = lengthOfTimeWeShouldUseToProcessThisMessage - \
             (time.time() - self.messageProcessingStartTime)
-        if sleepTime > 0 and doTimingAttackMitigation:
+        self._sleepForTimingAttackMitigation(sleepTime)
-            with shared.printLock:
-                print 'Timing attack mitigation: Sleeping for', sleepTime, 'seconds.'
-            time.sleep(sleepTime)
 
     # We have received a pubkey
     def recpubkey(self, data):
@@ -387,11 +389,7 @@ class receiveDataThread(threading.Thread):
         lengthOfTimeWeShouldUseToProcessThisMessage = .1
         sleepTime = lengthOfTimeWeShouldUseToProcessThisMessage - \
             (time.time() - self.pubkeyProcessingStartTime)
-        if sleepTime > 0 and doTimingAttackMitigation:
+        self._sleepForTimingAttackMitigation(sleepTime)
-            with shared.printLock:
-                print 'Timing attack mitigation: Sleeping for', sleepTime, 'seconds.'
-            time.sleep(sleepTime)
-
 
     # We have received an inv message
     def recinv(self, data):

src/class_singleListener.py

@@ -22,6 +22,11 @@ class singleListener(threading.Thread):
         self.selfInitiatedConnections = selfInitiatedConnections
 
     def run(self):
+        # If there is a trusted peer then we don't want to accept
+        # incoming connections so we'll just abandon the thread
+        if shared.trustedPeer:
+            return
+
         while shared.safeConfigGetBoolean('bitmessagesettings', 'dontconnect'):
             time.sleep(1)
         helper_bootstrap.dns()

src/helper_startup.py

@@ -12,6 +12,17 @@ from namecoin import ensureNamecoinOptions
 
 storeConfigFilesInSameDirectoryAsProgramByDefault = False  # The user may de-select Portable Mode in the settings if they want the config files to stay in the application data folder.
 
+def _loadTrustedPeer():
+    try:
+        trustedPeer = shared.config.get('bitmessagesettings', 'trustedpeer')
+    except ConfigParser.Error:
+        # This probably means the trusted peer wasn't specified so we
+        # can just leave it as None
+        return
+
+    host, port = trustedPeer.split(':')
+    shared.trustedPeer = shared.Peer(host, int(port))
+
 def loadConfig():
     if shared.appdata:
         shared.config.read(shared.appdata + 'keys.dat')
@@ -122,6 +133,8 @@ def loadConfig():
         with open(shared.appdata + 'keys.dat', 'wb') as configfile:
             shared.config.write(configfile)
 
+    _loadTrustedPeer()
+
 def isOurOperatingSystemLimitedToHavingVeryFewHalfOpenConnections():
     try:
         VER_THIS=StrictVersion(platform.version())

src/shared.py

@@ -92,6 +92,18 @@ namecoinDefaultRpcPort = "8336"
 # binary distributions vs source distributions.
 frozen = getattr(sys,'frozen', None)
 
+# If the trustedpeer option is specified in keys.dat then this will
+# contain a Peer which will be connected to instead of using the
+# addresses advertised by other peers. The client will only connect to
+# this peer and the timing attack mitigation will be disabled in order
+# to download data faster. The expected use case is where the user has
+# a fast connection to a trusted server where they run a BitMessage
+# daemon permanently. If they then run a second instance of the client
+# on a local machine periodically when they want to check for messages
+# it will sync with the network a lot faster without compromising
+# security.
+trustedPeer = None
+
 def isInSqlInventory(hash):
     queryreturn = sqlQuery('''select hash from inventory where hash=?''', hash)
     return queryreturn != []