Keychain and gpg-agent not getting along

Question

I have a problem with gpg-agent. I have been using the Funtoo keychain tool for a while, for my SSH keys exclusively. Works flawlessly - I log in, I call keychain, I type in my passphrases, and it caches my keys. Never get prompted for a passphrase during SSH connection attempts.
GPG is a different story. I have a GPG key, and I occasionally en- and decrypt files with it. So far so good. I also found out how to get keychain to cache the GPG key. It also picks up my gpg-agent, which is started as per the wiki entry (except that instead of putting it systemwide in /etc/profile.d, I put it in Openbox's ~/.config/openbox/environment file, which is where the SSH agent stuff is supposed to go as well.
Gpg-agent seemingly launches fine, it exports its environment variables just fine:
$ echo $GPG_AGENT_INFO
/tmp/gpg-3faT29/S.gpg-agent:2352:1
$ cat .gnupg/gpg-agent.env
GPG_AGENT_INFO=/tmp/gpg-3faT29/S.gpg-agent:2352:1
There's only one gpg-agent process running:
$ ps aux|grep gpg-agent
luser 2352 0.0 0.0 16252 1184 ? Ss 00:00 0:00 gpg-agent --daemon --write-env-file /home/stijn/.gnupg/gpg-agent.env
luser 3411 0.0 0.0 9276 1016 pts/0 S+ 00:16 0:00 grep gpg-agent
Keychain picks that up as well:
$ keychain --eval
* keychain 2.7.1 ~ http://www.funtoo.org
* Found existing ssh-agent: 2346
SSH_AUTH_SOCK=/tmp/ssh-YhDgORoL2345/agent.2345; export SSH_AUTH_SOCK;
SSH_AGENT_PID=2346; export SSH_AGENT_PID;
* Found existing gpg-agent: 2352
GPG_AGENT_INFO=/tmp/gpg-3faT29/S.gpg-agent:2352:1; export GPG_AGENT_INFO;
* Known ssh key: /home/stijn/.ssh/id_rsa-amalthea
* Known ssh key: /home/stijn/.ssh/id_rsa-athena
* Known ssh key: /home/stijn/.ssh/id_rsa-zeus
* Known ssh key: /home/stijn/.ssh/id_rsa-mnemosyne
* Known gpg key: [8 digit hex key]
However, when I open Mutt (or just try to decrypt about any GPG encrypted file), it will prompt me for the passphrase, despite the key already being cached. Passing --use-agent does not help (I also set that in ~/.gnupg/gpg.conf).
The bizarre thing being, of course, that the keychain-cached key did not get picked up, but if I enter my passphrase into the prompt I get the first time I call gpg, it does seem to get cached - I can open mutt, decrypt files, etc., it will all use that cached key.
Any tips? I get the feeling I'm missing something, but couldn't find what exactly.
Last edited by .:B:. (2011-12-06 22:25:27)

Answer 1

Gpg-agent by itself works fine, although I get the feeling that, a bit like sudo, there's an expiration date on the cached key - it seems I need to type the passphrase again after a few hours or so.
Either way, I'd love to get this working with keychain.