From 46a3de4b5acb37274ddd132499a3243e1f92b506 Mon Sep 17 00:00:00 2001
From: Werner Koch <wk@gnupg.org>
Date: Wed, 27 May 2020 11:27:32 +0200
Subject: [PATCH] card: Take care of removed and re-inserted cards.

* tools/gpg-card.c (cmd_list): Take care of the need_sn_cmd flag.
(cmd_factoryreset): Clear that flag.
(dispatch_command): Set flag after a reset and after a
CARD_NOT_PRESENT error.
--
---
 tools/gpg-card.c | 22 ++++++++++++++++++----
 tools/gpg-card.h |  1 +
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/tools/gpg-card.c b/tools/gpg-card.c
index 86ff8b111..76301eb31 100644
--- a/tools/gpg-card.c
+++ b/tools/gpg-card.c
@@ -1141,13 +1141,15 @@ cmd_list (card_info_t info, char *argstr)
       goto leave;
     }
 
-  if (!info->serialno)
+  if (!info->serialno || info->need_sn_cmd)
     {
-      /* This is probably the first call.  We need to send a SERIALNO
-       * command to scd so that our session knows all cards.  */
+      /* This is probably the first call or was explictly requested.
+       * We need to send a SERIALNO command to scdaemon so that our
+       * session knows all cards.  */
       err = scd_serialno (NULL, NULL);
       if (err)
         goto leave;
+      info->need_sn_cmd = 0;
       need_learn = 1;
     }
 
@@ -2807,6 +2809,8 @@ cmd_factoryreset (card_info_t info)
 
   /* Then, connect the card again.  */
   err = scd_serialno (NULL, NULL);
+  if (!err)
+    info->need_sn_cmd = 0;
 
  leave:
   if (err && any_apdu && !is_yubikey)
@@ -3272,6 +3276,8 @@ dispatch_command (card_info_t info, const char *orig_command)
         {
           flush_keyblock_cache ();
           err = scd_apdu (NULL, NULL, NULL, NULL);
+          if (!err)
+            info->need_sn_cmd = 1;
         }
       break;
 
@@ -3318,7 +3324,11 @@ dispatch_command (card_info_t info, const char *orig_command)
           err = 0;
         }
       else
-        log_error ("Command '%s' failed: %s\n", command, gpg_strerror (err));
+        {
+          log_error ("Command '%s' failed: %s\n", command, gpg_strerror (err));
+          if (gpg_err_code (err) == GPG_ERR_CARD_NOT_PRESENT)
+            info->need_sn_cmd = 1;
+        }
     }
   xfree (command);
 
@@ -3485,6 +3495,8 @@ interactive_loop (void)
             {
               flush_keyblock_cache ();
               err = scd_apdu (NULL, NULL, NULL, NULL);
+              if (!err)
+                info->need_sn_cmd = 1;
             }
           break;
 
@@ -3538,6 +3550,8 @@ interactive_loop (void)
                 break;
               }
           log_error ("Command '%s' failed: %s\n", s, gpg_strerror (err));
+          if (gpg_err_code (err) == GPG_ERR_CARD_NOT_PRESENT)
+            info->need_sn_cmd = 1;
         }
 
     } /* End of main menu loop. */
diff --git a/tools/gpg-card.h b/tools/gpg-card.h
index 9627e7b30..4bcb6488a 100644
--- a/tools/gpg-card.h
+++ b/tools/gpg-card.h
@@ -138,6 +138,7 @@ typedef struct key_info_s *key_info_t;
 struct card_info_s
 {
   int initialized;   /* True if a learn command was successful. */
+  int need_sn_cmd;   /* The SERIALNO command needs to be issued.  */
   int error;         /* private. */
   char *reader;      /* Reader information.  */
   char *cardtype;    /* NULL or type of the card.  */