Merge pull request #661 from Bitmessage/bpeel-ipv6

Bpeel ipv6

src/bitmessagemain.py

@@ -13,6 +13,9 @@ import signal  # Used to capture a Ctrl-C keypress so that Bitmessage can shutdo
 # The next 3 are used for the API
 import singleton
 import os
+import socket
+import ctypes
+from struct import pack
 
 from SimpleXMLRPCServer import SimpleXMLRPCServer
 from api import MySimpleXMLRPCRequestHandler
@@ -71,6 +74,56 @@ def connectToStream(streamNumber):
         a.setup(streamNumber, selfInitiatedConnections)
         a.start()
 
+def _fixWinsock():
+    if not ('win32' in sys.platform) and not ('win64' in sys.platform):
+        return
+
+    # Python 2 on Windows doesn't define a wrapper for
+    # socket.inet_ntop but we can make one ourselves using ctypes
+    if not hasattr(socket, 'inet_ntop'):
+        addressToString = ctypes.windll.ws2_32.WSAAddressToStringA
+        def inet_ntop(family, host):
+            if family == socket.AF_INET:
+                if len(host) != 4:
+                    raise ValueError("invalid IPv4 host")
+                host = pack("hH4s8s", socket.AF_INET, 0, host, "\0" * 8)
+            elif family == socket.AF_INET6:
+                if len(host) != 16:
+                    raise ValueError("invalid IPv6 host")
+                host = pack("hHL16sL", socket.AF_INET6, 0, 0, host, 0)
+            else:
+                raise ValueError("invalid address family")
+            buf = "\0" * 64
+            lengthBuf = pack("I", len(buf))
+            addressToString(host, len(host), None, buf, lengthBuf)
+            return buf[0:buf.index("\0")]
+        socket.inet_ntop = inet_ntop
+
+    # Same for inet_pton
+    if not hasattr(socket, 'inet_pton'):
+        stringToAddress = ctypes.windll.ws2_32.WSAStringToAddressA
+        def inet_pton(family, host):
+            buf = "\0" * 28
+            lengthBuf = pack("I", len(buf))
+            if stringToAddress(str(host),
+                               int(family),
+                               None,
+                               buf,
+                               lengthBuf) != 0:
+                raise socket.error("illegal IP address passed to inet_pton")
+            if family == socket.AF_INET:
+                return buf[4:8]
+            elif family == socket.AF_INET6:
+                return buf[8:24]
+            else:
+                raise ValueError("invalid address family")
+        socket.inet_pton = inet_pton
+
+    # These sockopts are needed on for IPv6 support
+    if not hasattr(socket, 'IPPROTO_IPV6'):
+        socket.IPPROTO_IPV6 = 41
+    if not hasattr(socket, 'IPV6_V6ONLY'):
+        socket.IPV6_V6ONLY = 27
 
 # This thread, of which there is only one, runs the API.
 class singleAPI(threading.Thread):
@@ -95,6 +148,8 @@ if shared.useVeryEasyProofOfWorkForTesting:
 
 class Main:
     def start(self, daemon=False):
+        _fixWinsock()
+
         shared.daemon = daemon
         # is the application already running?  If yes then exit.
         thisapp = singleton.singleinstance()

src/class_outgoingSynSender.py

@@ -55,7 +55,28 @@ class outgoingSynSender(threading.Thread):
             shared.alreadyAttemptedConnectionsListLock.release()
             timeNodeLastSeen = shared.knownNodes[
                 self.streamNumber][peer]
-            sock = socks.socksocket(socket.AF_INET, socket.SOCK_STREAM)
+            if peer.host.find(':') == -1:
+                address_family = socket.AF_INET
+            else:
+                address_family = socket.AF_INET6
+            try:
+                sock = socks.socksocket(address_family, socket.SOCK_STREAM)
+            except:
+                """
+                The line can fail on Windows systems which aren't
+                64-bit compatiable:
+                      File "C:\Python27\lib\socket.py", line 187, in __init__
+                        _sock = _realsocket(family, type, proto)
+                      error: [Errno 10047] An address incompatible with the requested protocol was used
+                      
+                So let us remove the offending address from our knownNodes file.
+                """
+                shared.knownNodesLock.acquire()
+                del shared.knownNodes[self.streamNumber][peer]
+                shared.knownNodesLock.release()
+                with shared.printLock:
+                    print 'deleting ', peer, 'from shared.knownNodes because it caused a socks.socksocket exception. We must not be 64-bit compatible.'
+                continue
             # This option apparently avoids the TIME_WAIT state so that we
             # can rebind faster
             sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

src/class_receiveDataThread.py

@@ -532,6 +532,32 @@ class receiveDataThread(threading.Thread):
 
         shared.broadcastToSendDataQueues((self.streamNumber, 'advertiseobject', hash))
     """
+
+    def _checkIPv4Address(self, host, hostFromAddrMessage):
+        # print 'hostFromAddrMessage', hostFromAddrMessage
+        if host[0] == '\x7F':
+            print 'Ignoring IP address in loopback range:', hostFromAddrMessage
+            return False
+        if host[0] == '\x0A':
+            print 'Ignoring IP address in private range:', hostFromAddrMessage
+            return False
+        if host[0:2] == '\xC0A8':
+            print 'Ignoring IP address in private range:', hostFromAddrMessage
+            return False
+        return True
+
+    def _checkIPv6Address(self, host, hostFromAddrMessage):
+        if host == ('\x00' * 15) + '\x01':
+            print 'Ignoring loopback address:', hostFromAddrMessage
+            return False
+        if host[0] == '\xFE' and (ord(host[1]) & 0xc0) == 0x80:
+            print 'Ignoring local address:', hostFromAddrMessage
+            return False
+        if (ord(host[0]) & 0xfe) == 0xfc:
+            print 'Ignoring unique local address:', hostFromAddrMessage
+            return False
+        return True
+
     # We have received an addr message.
     def recaddr(self, data):
         #listOfAddressDetailsToBroadcastToPeers = []
@@ -551,14 +577,11 @@ class receiveDataThread(threading.Thread):
 
         for i in range(0, numberOfAddressesIncluded):
             try:
-                if data[20 + lengthOfNumberOfAddresses + (38 * i):32 + lengthOfNumberOfAddresses + (38 * i)] != '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF':
+                fullHost = data[20 + lengthOfNumberOfAddresses + (38 * i):36 + lengthOfNumberOfAddresses + (38 * i)]
-                    with shared.printLock:
-                       print 'Skipping IPv6 address.', repr(data[20 + lengthOfNumberOfAddresses + (38 * i):32 + lengthOfNumberOfAddresses + (38 * i)])
-                    continue
             except Exception as err:
                 with shared.printLock:
                    sys.stderr.write(
-                       'ERROR TRYING TO UNPACK recaddr (to test for an IPv6 address). Message: %s\n' % str(err))
+                       'ERROR TRYING TO UNPACK recaddr (recaddrHost). Message: %s\n' % str(err))
                 break  # giving up on unpacking any more. We should still be connected however.
 
             try:
@@ -592,17 +615,18 @@ class receiveDataThread(threading.Thread):
                 break  # giving up on unpacking any more. We should still be connected however.
             # print 'Within recaddr(): IP', recaddrIP, ', Port',
             # recaddrPort, ', i', i
-            hostFromAddrMessage = socket.inet_ntoa(data[
+            if fullHost[0:12] == '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF':
-                                                   32 + lengthOfNumberOfAddresses + (38 * i):36 + lengthOfNumberOfAddresses + (38 * i)])
+                ipv4Host = fullHost[12:]
-            # print 'hostFromAddrMessage', hostFromAddrMessage
+                hostFromAddrMessage = socket.inet_ntop(socket.AF_INET, ipv4Host)
-            if data[32 + lengthOfNumberOfAddresses + (38 * i)] == '\x7F':
+                if not self._checkIPv4Address(ipv4Host, hostFromAddrMessage):
-                print 'Ignoring IP address in loopback range:', hostFromAddrMessage
                     continue
-            if data[32 + lengthOfNumberOfAddresses + (38 * i)] == '\x0A':
+            else:
-                print 'Ignoring IP address in private range:', hostFromAddrMessage
+                hostFromAddrMessage = socket.inet_ntop(socket.AF_INET6, fullHost)
+                if hostFromAddrMessage == "":
+                    # This can happen on Windows systems which are not 64-bit compatible 
+                    # so let us drop the IPv6 address. 
                     continue
-            if data[32 + lengthOfNumberOfAddresses + (38 * i):34 + lengthOfNumberOfAddresses + (38 * i)] == '\xC0A8':
+                if not self._checkIPv6Address(fullHost, hostFromAddrMessage):
-                print 'Ignoring IP address in private range:', hostFromAddrMessage
                     continue
             timeSomeoneElseReceivedMessageFromThisNode, = unpack('>Q', data[lengthOfNumberOfAddresses + (
                 38 * i):8 + lengthOfNumberOfAddresses + (38 * i)])  # This is the 'time' value in the received addr message. 64-bit.
@@ -688,8 +712,7 @@ class receiveDataThread(threading.Thread):
                 payload += pack('>I', self.streamNumber)
                 payload += pack(
                     '>q', 1)  # service bit flags offered by this node
-                payload += '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \
+                payload += shared.encodeHost(HOST)
-                    socket.inet_aton(HOST)
                 payload += pack('>H', PORT)  # remote port
         for (HOST, PORT), value in addrsInChildStreamLeft.items():
             timeLastReceivedMessageFromThisNode = value
@@ -700,8 +723,7 @@ class receiveDataThread(threading.Thread):
                 payload += pack('>I', self.streamNumber * 2)
                 payload += pack(
                     '>q', 1)  # service bit flags offered by this node
-                payload += '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \
+                payload += shared.encodeHost(HOST)
-                    socket.inet_aton(HOST)
                 payload += pack('>H', PORT)  # remote port
         for (HOST, PORT), value in addrsInChildStreamRight.items():
             timeLastReceivedMessageFromThisNode = value
@@ -712,8 +734,7 @@ class receiveDataThread(threading.Thread):
                 payload += pack('>I', (self.streamNumber * 2) + 1)
                 payload += pack(
                     '>q', 1)  # service bit flags offered by this node
-                payload += '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \
+                payload += shared.encodeHost(HOST)
-                    socket.inet_aton(HOST)
                 payload += pack('>H', PORT)  # remote port
 
         payload = encodeVarint(numberOfAddressesInAddrMessage) + payload

src/class_sendDataThread.py

@@ -113,8 +113,7 @@ class sendDataThread(threading.Thread):
                         payload += pack('>I', streamNumber)
                         payload += pack(
                             '>q', services)  # service bit flags offered by this node
-                        payload += '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \
+                        payload += shared.encodeHost(host)
-                            socket.inet_aton(host)
                         payload += pack('>H', port)
 
                     payload = encodeVarint(numberOfAddressesInAddrMessage) + payload

src/class_singleListener.py

@@ -4,6 +4,8 @@ import socket
 from class_sendDataThread import *
 from class_receiveDataThread import *
 import helper_bootstrap
+import errno
+import re
 
 # Only one singleListener thread will ever exist. It creates the
 # receiveDataThread and sendDataThread for each incoming connection. Note
@@ -21,6 +23,21 @@ class singleListener(threading.Thread):
     def setup(self, selfInitiatedConnections):
         self.selfInitiatedConnections = selfInitiatedConnections
 
+    def _createListenSocket(self, family):
+        HOST = ''  # Symbolic name meaning all available interfaces
+        PORT = shared.config.getint('bitmessagesettings', 'port')
+        sock = socket.socket(family, socket.SOCK_STREAM)
+        if family == socket.AF_INET6:
+            # Make sure we can accept both IPv4 and IPv6 connections.
+            # This is the default on everything apart from Windows
+            sock.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 0)
+        # This option apparently avoids the TIME_WAIT state so that we can
+        # rebind faster
+        sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        sock.bind((HOST, PORT))
+        sock.listen(2)
+        return sock
+
     def run(self):
         while shared.safeConfigGetBoolean('bitmessagesettings', 'dontconnect'):
             time.sleep(1)
@@ -35,14 +52,22 @@ class singleListener(threading.Thread):
         with shared.printLock:
             print 'Listening for incoming connections.'
 
-        HOST = ''  # Symbolic name meaning all available interfaces
+        # First try listening on an IPv6 socket. This should also be
-        PORT = shared.config.getint('bitmessagesettings', 'port')
+        # able to accept connections on IPv4. If that's not available
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        # we'll fall back to IPv4-only.
-        # This option apparently avoids the TIME_WAIT state so that we can
+        try:
-        # rebind faster
+            sock = self._createListenSocket(socket.AF_INET6)
-        sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        except socket.error, e:
-        sock.bind((HOST, PORT))
+            if (isinstance(e.args, tuple) and
-        sock.listen(2)
+                e.args[0] in (errno.EAFNOSUPPORT,
+                              errno.EPFNOSUPPORT,
+                              errno.ENOPROTOOPT)):
+                sock = self._createListenSocket(socket.AF_INET)
+            else:
+                raise
+
+        # regexp to match an IPv4-mapped IPv6 address
+        mappedAddressRegexp = re.compile(r'^::ffff:([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)$')
 
         while True:
             # We typically don't want to accept incoming connections if the user is using a
@@ -56,18 +81,29 @@ class singleListener(threading.Thread):
                     print 'We are connected to too many people. Not accepting further incoming connections for ten seconds.'
 
                 time.sleep(10)
-            a, (HOST, PORT) = sock.accept()
 
-            # The following code will, unfortunately, block an incoming
+            while True:
-            # connection if someone else on the same LAN is already connected
+                a, sockaddr = sock.accept()
-            # because the two computers will share the same external IP. This
+                (HOST, PORT) = sockaddr[0:2]
-            # is here to prevent connection flooding.
+
-            while HOST in shared.connectedHostsList:
+                # If the address is an IPv4-mapped IPv6 address then
+                # convert it to just the IPv4 representation
+                md = mappedAddressRegexp.match(HOST)
+                if md != None:
+                    HOST = md.group(1)
+
+                # The following code will, unfortunately, block an
+                # incoming connection if someone else on the same LAN
+                # is already connected because the two computers will
+                # share the same external IP. This is here to prevent
+                # connection flooding.
+                if HOST in shared.connectedHostsList:
+                    a.close()
                     with shared.printLock:
                         print 'We are already connected to', HOST + '. Ignoring connection.'
+                else:
+                    break
 
-                a.close()
-                a, (HOST, PORT) = sock.accept()
             someObjectsOfWhichThisRemoteNodeIsAlreadyAware = {} # This is not necessairly a complete list; we clear it from time to time to save memory.
             sendDataThreadQueue = Queue.Queue() # Used to submit information to the send data thread for this connection.
             a.settimeout(20)

src/shared.py

@@ -96,6 +96,13 @@ def isInSqlInventory(hash):
     queryreturn = sqlQuery('''select hash from inventory where hash=?''', hash)
     return queryreturn != []
 
+def encodeHost(host):
+    if host.find(':') == -1:
+        return '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \
+            socket.inet_aton(host)
+    else:
+        return socket.inet_pton(socket.AF_INET6, host)
+
 def assembleVersionMessage(remoteHost, remotePort, myStreamNumber):
     payload = ''
     payload += pack('>L', 2)  # protocol version.
@@ -104,8 +111,7 @@ def assembleVersionMessage(remoteHost, remotePort, myStreamNumber):
 
     payload += pack(
         '>q', 1)  # boolservices of remote connection; ignored by the remote host.
-    payload += '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xFF\xFF' + \
+    payload += encodeHost(remoteHost)
-        socket.inet_aton(remoteHost)
     payload += pack('>H', remotePort)  # remote IPv6 and port
 
     payload += pack('>q', 1)  # bitflags of the services I offer.