initial wireshark dissector

Signed-off-by: Asbjørn Sloth Tønnesen <asbjorn@asbjorn.biz>

diff --git a/wireshark/nsdp.lua b/wireshark/nsdp.lua
new file mode 100644 (file)
index 0000000..897f1b1
--- /dev/null
+++ b/wireshark/nsdp.lua
@@ -0,0 +1,79 @@
+-- create nsdp protocol and its fields
+p_nsdp = Proto ("nsdp","Netgear Switch Description Protocol")
+-- local f_source = ProtoField.uint16("nsdp.src", "Source", base.HEX)
+local f_type = ProtoField.uint16("nsdp.type", "Type", base.HEX)
+local f_source = ProtoField.ether("nsdp.src", "Source", base.HEX)
+local f_destination = ProtoField.ether("nsdp.dst", "Destination", base.HEX)
+local f_seq = ProtoField.uint16("nsdp.seq", "Seq", base.HEX)
+local f_data = ProtoField.string("nsdp.data", "Data", FT_STRING)
+local f_cmd = ProtoField.uint16("nsdp.cmd", "Command", base.HEX)
+local f_password = ProtoField.string("nsdp.password", "Password", FT_STRING)
+local f_newpassword = ProtoField.string("nsdp.newpassword", "New password", FT_STRING)
+
+--local f_debug = ProtoField.uint8("nsdp.debug", "Debug")
+p_nsdp.fields = {f_type,f_source,f_destination,f_seq,f_cmd,f_password,f_newpassword}
+
+-- nsdp dissector function
+function p_nsdp.dissector (buf, pkt, root)
+  -- validate packet length is adequate, otherwise quit
+  if buf:len() == 0 then return end
+  pkt.cols.protocol = p_nsdp.name
+
+  -- create subtree for nsdp
+  subtree = root:add(p_nsdp, buf(0))
+  local offset = 0
+  local ptype = buf(offset,2):uint()
+  subtree:add(f_type, ptype)
+  offset = offset + 8
+  subtree:add(f_source, buf(offset,6))
+  offset = offset + 6
+  subtree:add(f_destination, buf(offset,6))
+  offset = offset + 8
+  subtree:add(f_seq, buf(offset,2))
+  offset = offset + 10
+  local cmd = 0
+  if offset < buf:len() then
+    cmd = buf(offset, 2):uint()
+    offset = offset + 2
+  end
+  subtree:add(f_cmd, cmd)
+
+  if cmd == 1 then
+    subtree:append_text(", init")
+  elseif cmd == 0xa or (ptype == 0x0104 and cmd == 0) then
+    if ptype == 0x0103 then
+      local pw_len = buf(offset, 2):uint()
+      offset = offset + 2
+      subtree:add(f_password, buf(offset,pw_len))
+      offset = offset + pw_len
+      local next_up = buf(offset, 2):uint()
+      offset = offset + 2
+      if next_up == 0x0009 then
+        subtree:append_text(", reset password")
+        pw_len = buf(offset, 2):uint()
+        offset = offset + 2
+        subtree:add(f_newpassword, buf(offset,pw_len))
+      else
+        subtree:append_text(", login")
+      end
+    elseif ptype == 0x0104 then
+      if buf:len() == offset then
+        subtree:append_text(", password changed")
+      else
+        subtree:append_text(", logged in")
+      end
+    end
+  end
+end
+
+function p_nsdp.init()
+  -- init
+end
+
+local tcp_dissector_table = DissectorTable.get("udp.port")
+dissector = tcp_dissector_table:get_dissector(63321)
+tcp_dissector_table:add(63321, p_nsdp)
+
+local tcp_dissector_table = DissectorTable.get("udp.port")
+dissector = tcp_dissector_table:get_dissector(63322)
+tcp_dissector_table:add(63322, p_nsdp)