LUA dissector field in display filter

Hi,

I'm trying to register some fields within a dissector, to be able to use them in the display filter. Tried different things but none of them worked, a simple example below :

DUMMYPROTOCOL = Proto ("DUMMYPROTOCOL", "B tcp Protocol")
magic = ProtoField.uint32 ("DUMMYPROTOCOL.magic", "Magic")
DUMMYPROTOCOL.fields = { magic }
function DUMMYPROTOCOL.dissector (buffer, pinfo, tree)
subtree = tree:add (DUMMYPROTOCOL, buffer())
– Modify columns
pinfo.cols.protocol = DUMMYPROTOCOL.name
pinfo.cols.info = "PROTOCOL B"
subtree:add("hey")
local offset = 0
while ( offset < buffer:len() - 4) do
if buffer(offset,4):uint() == 0x12345678 then
subtree:add(magic,buffer(offset,4))
break
end
offset = offset + 1
end

end

The field doesn’t seem to be registered properly, I get “isn’t a valid display filter” “dommyprotocol.magic” is neither a field nor a protocol name, when trying to search for it. Any ideas ?

Thanks