Add wireshark dissector for control protocol

LuaScripts/gridctl.lua

@@ -0,0 +1,86 @@
+local pf_type = ProtoField.uint16("gridctl.type", "Packet Type", base.HEX)
+local pf_paylen = ProtoField.uint32("gridctl.paylen", "Payload Length", base.DEC)
+local pf_payload = ProtoField.bytes("gridctl.payload", "Payload bytes")
+local pf_payload32 = ProtoField.uint32("gridctl.payload32", "Payload as 32-bit LE integer", base.DEC)
+local pf_payload16 = ProtoField.uint16("gridctl.payload16", "Payload as 16-bit LE integer", base.HEX)
+local pf_response = ProtoField.uint16("gridctl.response", "Response code", base.HEX)
+local pf_origtype = ProtoField.uint16("gridctl.origtype", "Original request type", base.HEX)
+
+p_gridctl = Proto ("GridCtl", "Nvidia GRID Control Protocol")
+
+p_gridctl.fields = {
+    pf_type,
+    pf_paylen,
+    pf_payload,
+    pf_payload16,
+    pf_payload32,
+    pf_response,
+    pf_origtype
+}
+
+function p_gridctl.dissector(buf, pkt, root)
+    pkt.cols.protocol = p_gridctl.name
+    
+    subtree = root:add(p_gridctl, buf(0))
+    
+    -- We can have multiple GRID control packets in one TCP datagram
+    i = 0
+    while i < buf:len() do
+        -- Make sure we have a full header
+        if buf:len() - i < 4 then
+            -- We need more data
+            pkt.desegment_len = DESEGMENT_ONE_MORE_SEGMENT
+            pkt.desegment_offset = 0
+        end
+        
+        -- Read the packet type field
+        ptype = buf(i, 2):le_uint()
+        subtree:add(pf_type, buf(i, 2), ptype)
+        i = i + 2
+        
+        -- Read the payload length field
+        paylen = buf(i, 2):le_uint()
+        subtree:add(pf_paylen, buf(i, 2), paylen)
+        i = i + 2
+        
+        -- Make sure we have the full payload
+        if buf:len() - i < paylen then
+            -- We need more data
+            pkt.desegment_len = DESEGMENT_ONE_MORE_SEGMENT
+            pkt.desegment_offset = 0
+        end
+        
+        -- Decode responses differently
+        if ptype == 0x0204 then
+            origtype = buf(i, 2):le_uint()
+            subtree:add(pf_origtype, buf(i, 2), origtype)
+            i = i + 2
+            response = buf(i, 2):le_uint()
+            subtree:add(pf_response, buf(i, 2), response)
+            i = i + 2
+        else
+            if paylen == 4 then
+                -- Display the payload as a uint32 (LE)
+                payload32 = buf(i, 4):le_uint()
+                subtree:add(pf_payload32, buf(i, 4), payload32)
+            elseif paylen == 2 then
+                -- Display the payload as a uint16 (LE)
+                payload16 = buf(i, 2):le_uint()
+                subtree:add(pf_payload16, buf(i, 2), payload16)
+            elseif paylen ~= 0 then
+                subtree:add(pf_payload, buf(i, paylen))
+            end
+            i = i + paylen
+        end
+
+        if i ~= buf:len() then
+            subtree:add("")
+        end
+    end
+end
+
+function p_gridctl.init()
+end
+
+local tcp_dissector_table = DissectorTable.get("tcp.port")
+tcp_dissector_table:add(47995, p_gridctl)