On Sep 24, 2009, at 3:00 PM, Borz, John (IPG-Roseville R&D) wrote:
That's what I was looking for. I would like to extend a production
Wireshark installation to support decoding these options similar to
the new dissector DLL plugin model. Is this possible with the
built-in dissectors?
The dissector plugin model allows a dissector to be plugged into any
dissector table; this means that there already needs to be a dissector
that registers that table.
Currently, the BOOTP dissector doesn't register any such table, so, as
I said, there is currently no mechanism to do what you want to do.
You would have to change the BOOTP dissector in order to do that; that
would require you to get the Wireshark source, change it, compile it,
and distribute that modified version of Wireshark, along with the
plugin.
Wireshark 1.2 has a limited ability to support custom DHCP options
without changing the code. There is a "Custom BootP/DHCP Options"
preference, which takes a string of the form
176,MyOption,string;242,NewOption,ipv4
i.e., a semicolon-separated list of options, where each option is a
comma-separated list with:
option number - a value between 1 and 254
option name - the name for the option
option type:
string, for an option that's a character string;
ipv4, for an option that's an IPv4 address;
bytes, for an option that's an opaque blob of bytes.
If your option is more complicated than that, this feature cannot
support it.