agent: Create and use Token entries to track the display s/n.

* agent/findkey.c (agent_write_private_key): Add arg dispserialno and
update the token.
(agent_write_shadow_key): Add arg dispserialno and adjust all callers.
--

GnuPG-bug-id: 6135

Note that this has been forward ported from 2.2

1 files changed, 8 insertions, 1 deletions

diff --git a/agent/pksign.c b/agent/pksign.c
index dfed0e398..a7b5c579f 100644
--- a/agent/pksign.c
+++ b/agent/pksign.c
@@ -372,8 +372,15 @@ agent_pksign_do (ctrl_t ctrl, const char *cache_nonce,
             }
 
           if (keyref)
-            agent_write_shadow_key (ctrl->keygrip, serialno, keyref, pkbuf, 0);
+            {
+              char *dispserialno;
 
+              agent_card_getattr (ctrl, "$DISPSERIALNO", &dispserialno,
+                                  hexgrip);
+              agent_write_shadow_key (ctrl->keygrip, serialno, keyref, pkbuf,
+                                      0, dispserialno);
+              xfree (dispserialno);
+            }
           algo = get_pk_algo_from_key (s_pkey);
 
           xfree (serialno);