Fwd: GnuPG maintainer wanted

Charles Wilson cygwin@cwilson.fastmail.fm
Mon Feb 27 15:27:00 GMT 2012

On 2/27/2012 8:56 AM, marco atzeri wrote:
> I will give a look.
> Any preference between 1.4.12 and 2.0.18 ?

I made an attempt about two years ago to port gnupg 2.x.  It has
additional dependencies beyond those of 1.4.x, so I added all of those
to the distro.

However, I ran into a problem (related to pth/pthread support) such
gnugp's analog to ssh-agent could not be queried, so you always had to
type in your passphrase.  That was obviously unacceptable, so I didn't
actually post my version of gnupg-2.x

The problem was basically this:

1) gnupg requires threading support via pth, NOT pthreads. This is
because the gnupg folks consider "real" threads to provide a larger
"attack surface" for security -- too large to adequately secure on all
supported platforms -- so they require the use of the pth library. (pth
provides a pseudo-thread interface that "kinda" works like pthreads, but
the "threads" are actually all cooperatively managed as part of a single
"native" thread.)

2) The pth library doesn't/didn't work on cygwin because of missing
support for pth+fork. In any case, pth needed support for a facility
that was, at the time, missing from cygwin (standard posix
sigstack/sigaltstack approach):
This was on cgf's post-1.7 TODO list, but I don't recall if it ever
happened. If it did, then I have a "ported" pth package (un-ITP'ed) that
should work.

3) So, I heavily patched gnupg to use pthreads instead. But this had a
side effect that gpg-agent didn't work as expected. IIRC, this had
(something) to do with cygwin's missing support for passing open file
descriptors between threads (briefly mentioned on the main list last
week; obviously passing open filedes between *pseudo-threads* that are
actually part of the same *real* thread, as in pth, is not a problem. If
we were actually using pth.

I suspect, if (a) cygwin has sigstack/sigaltstack, and (b) my ported pth
works ok, then a version of gnupg-2.x with my pthread patches reverted
should be "almost there".


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