Merged in gvaladon/scapy-issues/Patch for PR#82 (pull request phaethon#137)

Patch for the issue from pull request phaethon#82

Author: p-l-

scapy/layers/dhcp6.py

@@ -894,13 +894,6 @@ class DHCP6OptRelayAgentERO(_DHCP6OptGuessPayload):       # RFC4994
 #            INFORMATION REQUEST
 # - relay  : RELAY-FORW (toward server)
 
-class _DHCP6GuessPayload(Packet):
-    def guess_payload_class(self, payload):
-        if len(payload) > 1 :
-            print ord(payload[0])
-            return get_cls(dhcp6opts.get(ord(payload[0]),"DHCP6OptUnknown"), conf.raw_layer)
-        return conf.raw_layer
-
 #####################################################################
 ## DHCPv6 messages sent between Clients and Servers (types 1 to 11)
 # Comme specifie en section 15.1 de la RFC 3315, les valeurs de
@@ -1137,7 +1130,7 @@ class DHCP6_InfoRequest(DHCP6):
 # address or other multicast addresses, it sets the Hop Limit field to
 # 32. 
 
-class DHCP6_RelayForward(_DHCP6GuessPayload,Packet):
+class DHCP6_RelayForward(_DHCP6OptGuessPayload,Packet):
     name = "DHCPv6 Relay Forward Message (Relay Agent/Server Message)"
     fields_desc = [ ByteEnumField("msgtype", 12, dhcp6types),
                     ByteField("hopcount", None),

test/regression.uts

@@ -3737,6 +3737,11 @@ str(DHCP6_RelayForward()) == '\x0c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x
 a=DHCP6_RelayForward('\x0c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
 a.msgtype == 12 and a.hopcount == 0 and a.linkaddr == "::" and a.peeraddr == "::"
 
+= DHCP6_RelayForward - Dissection with options
+a = DHCP6_RelayForward('\x0c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\t\x00\x04\x00\x01\x00\x00')
+a.msgtype == 12 and DHCP6OptRelayMsg in a and DHCP6OptClientId in a
+
+
 #####################################################################
 + Test DHCP6 Messages - DHCP6_RelayReply