gpg: use gpgconf to get correct GPG agent UNIX socket path

trezor_agent/gpg/__main__.py

@@ -60,9 +60,9 @@ def run_create(args):
     sys.stdout.write(protocol.armor(result, 'PUBLIC KEY BLOCK'))
 
 
-def run_agent(args):
+def run_agent(args):  # pylint: disable=unused-argument
     """Run a simple GPG-agent server."""
-    sock_path = os.path.expanduser(args.sock_path)
+    sock_path = keyring.get_agent_sock_path()
     with server.unix_domain_socket_server(sock_path) as sock:
         for conn in agent.yield_connections(sock):
             with contextlib.closing(conn):
@@ -84,7 +84,6 @@ def main():
     create_cmd.set_defaults(run=run_create)
 
     agent_cmd = subparsers.add_parser('agent')
-    agent_cmd.add_argument('-s', '--sock-path', default='~/.gnupg/S.gpg-agent')
     agent_cmd.set_defaults(run=run_agent)
 
     args = p.parse_args()

trezor_agent/gpg/keyring.py

@@ -13,9 +13,16 @@ from .. import util
 log = logging.getLogger(__name__)
 
 
-def connect_to_agent(sock_path='~/.gnupg/S.gpg-agent', sp=subprocess):
+def get_agent_sock_path(sp=subprocess):
+    """Parse gpgconf output to find out GPG agent UNIX socket path."""
+    lines = sp.check_output(['gpgconf', '--list-dirs']).strip().split('\n')
+    dirs = dict(line.split(':', 1) for line in lines)
+    return dirs['agent-socket']
+
+
+def connect_to_agent(sp=subprocess):
     """Connect to GPG agent's UNIX socket."""
-    sock_path = os.path.expanduser(sock_path)
+    sock_path = get_agent_sock_path(sp=sp)
     sp.check_call(['gpg-connect-agent', '/bye'])
     sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
     sock.connect(sock_path)