Re: [Sks-devel] Keydump file format documentation?

[Phil Pennock]

On 2014-03-12 at 11:35 -0700, Philip White wrote:
> I want to develop a program that analyzes the PGP web of trust. To do this, I 
> figure the best source is the keydump file. The problem is, it's a binary 
> file and I don't see any documentation for the binary file format. Given 
> enough time and effort I can probably read the source code of `sksserver` and 
> figure out how the file is encoded, but I wonder if there's a better way.
> 
> Has anyone documented the file format? Alternately, is anyone willing to 
> document it?
> 
> P.S. I don't want to develop my program in O'Caml, if I can help it, so I 
> don't want to simply reuse the file parsing libraries. :)

Your first tool for debugging a file format is the "file" command, which
might be used like this:

    % file sks-dump-0000.pgp
    sks-dump-0000.pgp: GPG key public ring

The answer might be wrong, but it provides a good starting point for
investigation.  In this case, the answer is mostly correct (except that
it's not GPG-specific).

You can find documentation in RFC 4880.  It actually doesn't say much
and disavows full knowledge, but the "Traditionally, a keyring is simply
a sequential list of keys" comment may help.

You can get an overview using gpg like so:

    % gpg --list-packets < sks-dump-0000.pgp | less

and you can find parsing libraries in various languages.

-Phil