Hey Guys,
I`m writing a plugin to dissect a protocol the company I`m working for
uses and i have one problem, that no readme or developer guide could
solve yet.
The problem is that many parts of the protocol do not always consist of
the same amount of bytes. Therefore the bytes have to be decoded that
way (java code):
int decode(bytestream stream){
int b = stream.readByte();
int t = b;
while(b > 127){
b = stream.readByte();
t = (t << 7)) | b;
}
return t;
}
Do get the right value is not the problem, but to register the header
field and to make it filterable. When I try to register it with the
array hf_register_info I have to specify a data type like FT_UINT8. But
setting up the header fields with the right amount of bytes of tvb when
dissecting the packet results in a wrong value, because the bytes have
to be encoded in the way I`ve mentioned it.
Is there a possibility to register a header field with e.t. FT_UINT32
and changing the value afterwards? Or is it possible to filter header
fields that are added with proto_tree_add_text or add_value? Another way
could be to get the specified bytes of tvb, to encode it the right way
and then wright it back to tvb, but i did not found a possibility to do
that.
I would be very glad to hear any suggestions.
thx
