feature: added pcapConverter to decode pcap logs

pcapConverter.py

@@ -0,0 +1,45 @@
+
+# pcap Converter
+#
+# This little helper tool read a network trace (e.g. recorded with wireshark) and
+# interprets the content of the EXI.V2GTP.TCP.IPv6 data.
+#
+# Preconditions:
+# 1. You have a capture file with contains V2G traffic (pcap or pcapng file).
+# 2. You installed the python library pyshark, according to https://github.com/KimiNewt/pyshark/
+#    pip install pyshark
+# 3. You cloned and compiled the OpenV2Gx EXI decoder from https://github.com/uhi22/OpenV2Gx 
+
+import pyshark
+import exiConnector
+
+inputFileName = "efcaec23.pcap"
+cap = pyshark.FileCapture(inputFileName, display_filter="ipv6")
+fileOut = open(inputFileName + '.decoded.txt', 'w')
+#print(cap)
+#print(cap[0])
+#print(cap[1])
+#print(dir(cap[1]))
+#print(cap[1].sniff_time) # readable time
+#print(cap[1].sniff_timestamp) # epoch time
+numberOfPackets=0
+for packet in cap:
+    numberOfPackets+=1
+    #print(packet)
+    if 'TCP' in packet:
+        #print(packet.tcp.field_names)
+        if ('payload' in packet.tcp.field_names):
+            tcppayload = packet.tcp.payload # this gives a string of hex values, separated by ":", e.g. "01:fe:80:01"
+            s = tcppayload.replace(":", "") # remove colons
+            if (s[0:8]=="01fe8001"):
+                # it is a V2GTP header with EXI content
+                strExi = s[16:] # remove V2GTP header (8 bytes, means 16 hex characters)
+                sHeader = "Packet #" + str(numberOfPackets) + " [" + str(packet.sniff_time) + "] " + strExi + " means:"
+                pre = "DD" # decode DIN
+                decoded=exiConnector.exiDecode(strExi, pre)
+                print(sHeader)
+                print(decoded)
+                print(sHeader, file=fileOut)
+                print(decoded, file=fileOut)
+fileOut.close()
+