signing commits with openssl/PKCS#11

Hy!

I would like to sign each commit with a X.509 certificate and a private key 
stored on a PKCS#11 token. I assume that that should be possible somehow using 
a hook which calls openssl. Does somebody know a working implementation of 
this?

cheers
Mat

Mat Arge venit, vidit, dixit 22.10.2012 15:38:

Hy!

I would like to sign each commit with a X.509 certificate and a private key 
stored on a PKCS#11 token. I assume that that should be possible somehow using 
a hook which calls openssl. Does somebody know a working implementation of 
this?

cheers
Mat

In principle, we have an almost pluggable architecture. See for example
the latter part of the 2nd post in

http://article.gmane.org/gmane.comp.version-control.git/175127

Unless you want to change git itself, you're probably better off storing
your non-gpg signatures in a note (or a self-created signed tag). To
sign the commit rev, you could sign the output of "git cat-file commit
rev" (or of "git rev-parse rev") and store that signature in a note that
commit. To verify, you verify the note against the commit.

Michael

On Mon, Oct 22, 2012 at 6:38 AM, Mat Arge [off-list ref] wrote:

Hy!

I would like to sign each commit with a X.509 certificate and a private key
stored on a PKCS#11 token. I assume that that should be possible somehow using
a hook which calls openssl. Does somebody know a working implementation of
this?

Creating signatures from an rsa key on a pkcs11 token should be
possible, but gnupg doesn't support pkcs11 for philosophical reasons.
You need to use gnupg-pkcs11 which is maintained outside of the gnupg
tree.

Once you configure gnupg-pkcs11-scd, you'll be able to use git and gpg
to sign tags as usual.

I configured this a while back for use with CAC cards using the
following resources:

   http://alpha.uwb.edu.pl/map/eToken_gpg_howto.shtml (dead)
   http://alpha.uwb.edu.pl/amicke/eToken_gpg_howto.shtml (replacement
for above?)
   http://gnupg-pkcs11.sourceforge.net/man.html

Try those docs.  If you have questions, I'll try to find my notes.

-Brandon

On Wednesday 24. October 2012 11:46:15 Michael J Gruber wrote:

Mat Arge venit, vidit, dixit 22.10.2012 15:38:

quoted

Hy!

I would like to sign each commit with a X.509 certificate and a private
key
stored on a PKCS#11 token. I assume that that should be possible somehow
using a hook which calls openssl. Does somebody know a working
implementation of this?

cheers
Mat

In principle, we have an almost pluggable architecture. See for example
the latter part of the 2nd post in

http://article.gmane.org/gmane.comp.version-control.git/175127

Unless you want to change git itself, you're probably better off storing
your non-gpg signatures in a note (or a self-created signed tag). 

So, there is no possibility to modify the commit itself via a hook, and add a, 
say, "opensslsig" instead of a gpgsig tag?

To
sign the commit rev, you could sign the output of "git cat-file commit
rev" (or of "git rev-parse rev") and store that signature in a note that
commit. To verify, you verify the note against the commit.

Michael

But if I crete/modify a signature file while commiting, that file wouldn't be 
commited itself, so the signatur-file would always be one commit behind. Or am 
I missing something? I'm quite new to git (or DVCSs in general), so sorry if 
this is a dumb question.

cheers
Mat

On Thursday 25. October 2012 01:02:33 Brandon Casey wrote:

On Mon, Oct 22, 2012 at 6:38 AM, Mat Arge [off-list ref] wrote:

quoted

Hy!

I would like to sign each commit with a X.509 certificate and a private
key
stored on a PKCS#11 token. I assume that that should be possible somehow
using a hook which calls openssl. Does somebody know a working
implementation of this?

Creating signatures from an rsa key on a pkcs11 token should be
possible, but gnupg doesn't support pkcs11 for philosophical reasons.
You need to use gnupg-pkcs11 which is maintained outside of the gnupg
tree.

Once you configure gnupg-pkcs11-scd, you'll be able to use git and gpg
to sign tags as usual.

I configured this a while back for use with CAC cards using the
following resources:

   http://alpha.uwb.edu.pl/map/eToken_gpg_howto.shtml (dead)
   http://alpha.uwb.edu.pl/amicke/eToken_gpg_howto.shtml (replacement
for above?)
   http://gnupg-pkcs11.sourceforge.net/man.html

Try those docs.  If you have questions, I'll try to find my notes.

-Brandon

Thanks for the tip, I will try them (though the appear to be very outdated).
Do you know, if gnupg-pkcs11-scd is able to cooperate with the standard pcscd 
from pcsc-lite, or is a one-or-the-other situation?

cheers
Mat