scd: Add --demand option for SERIALNO.

* scd/app.c (select_application): Add SERIALNO_BIN and SERIALNO_BIN_LEN
arguments.  Return matched APP with a serial number when specified.
* scd/command.c (open_card): Modify for the implicit open only.
(open_card_with_request): New for explicit open and support match with a
serial number.
(cmd_serialno): Support --demand option.
(cmd_learn, cmd_readcert, cmd_readkey, cmd_pksign, cmd_pkauth)
(cmd_pkdecrypt, cmd_getattr, cmd_setattr, cmd_writecert, cmd_writekey)
(cmd_genkey, cmd_random, cmd_passwd, cmd_checkpin, cmd_apdu): Follow
the change of open_card.

Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

scd/app-common.h

@@ -129,7 +129,8 @@ void application_notify_card_reset (int slot);
 gpg_error_t check_application_conflict (const char *name, app_t app);
 gpg_error_t app_reset (app_t app, ctrl_t ctrl, int send_reset);
 gpg_error_t select_application (ctrl_t ctrl, const char *name, app_t *r_app,
-                                int scan);
+                                int scan, const unsigned char *serialno_bin,
+                                size_t serialno_bin_len);
 char *get_supported_applications (void);
 void release_application (app_t app);
 gpg_error_t app_munge_serialno (app_t app);

scd/app.c

@@ -317,10 +317,12 @@ app_new_register (int slot, ctrl_t ctrl, const char *name)
    and return a context.  Returns an error code and stores NULL at
    R_APP if no application was found or no card is present. */
 gpg_error_t
-select_application (ctrl_t ctrl, const char *name, app_t *r_app, int scan)
+select_application (ctrl_t ctrl, const char *name, app_t *r_app,
+                    int scan, const unsigned char *serialno_bin,
+                    size_t serialno_bin_len)
 {
   gpg_error_t err = 0;
-  app_t app;
+  app_t a;
 
   *r_app = NULL;
 
@@ -352,33 +354,50 @@ select_application (ctrl_t ctrl, const char *name, app_t *r_app, int scan)
 
           if (!sw || sw == SW_HOST_ALREADY_CONNECTED)
             err = 0;
+          else if (sw == SW_HOST_NO_CARD)
+            err = gpg_error (GPG_ERR_CARD_NOT_PRESENT);
           else
             err = gpg_error (GPG_ERR_ENODEV);
 
           if (!err)
             err = app_new_register (slot, ctrl, name);
           else
+            {
+              /* We close a reader with no card.  */
               apdu_close_reader (slot);
             }
+        }
 
       apdu_dev_list_finish (l);
     }
 
-  app = app_top;
+  npth_mutex_lock (&app_list_lock);
-  if (app)
+  for (a = app_top; a; a = a->next)
     {
-      lock_app (app, ctrl);
+      lock_app (a, ctrl);
-      err = check_conflict (app, name);
+      if (serialno_bin == NULL)
+        break;
+      if (a->serialnolen == serialno_bin_len
+          && !memcmp (a->serialno, serialno_bin, a->serialnolen))
+        break;
+      unlock_app (a);
+    }
+
+  if (a)
+    {
+      err = check_conflict (a, name);
       if (!err)
         {
-          app->ref_count++;
+          a->ref_count++;
-          *r_app = app;
+          *r_app = a;
         }
-      unlock_app (app);
+      unlock_app (a);
     }
   else
     err = gpg_error (GPG_ERR_ENODEV);
 
+  npth_mutex_unlock (&app_list_lock);
+
   return err;
 }
 

scd/command.c

@@ -193,10 +193,8 @@ option_handler (assuan_context_t ctx, const char *key, const char *value)
 
 /* If the card has not yet been opened, do it.  */
 static gpg_error_t
-open_card (ctrl_t ctrl, const char *apptype, int scan)
+open_card (ctrl_t ctrl)
 {
-  gpg_error_t err;
-
   /* If we ever got a card not present error code, return that.  Only
      the SERIALNO command and a reset are able to clear from that
      state. */
@@ -206,24 +204,46 @@ open_card (ctrl_t ctrl, const char *apptype, int scan)
   if ( IS_LOCKED (ctrl) )
     return gpg_error (GPG_ERR_LOCKED);
 
+  if (ctrl->app_ctx)
+    return 0;
+
+  return select_application (ctrl, NULL, &ctrl->app_ctx, 0, NULL, 0);
+}
+
+/* Explicitly open a card for a specific use of APPTYPE or SERIALNO.  */
+static gpg_error_t
+open_card_with_request (ctrl_t ctrl, const char *apptype, const char *serialno)
+{
+  gpg_error_t err;
+  unsigned char *serialno_bin = NULL;
+  size_t serialno_bin_len = 0;
+
   /* If we are already initialized for one specific application we
      need to check that the client didn't requested a specific
      application different from the one in use before we continue. */
-  if (!scan && ctrl->app_ctx)
+  if (apptype && ctrl->app_ctx)
     return check_application_conflict (apptype, ctrl->app_ctx);
 
-  err = select_application (ctrl, apptype, &ctrl->app_ctx, scan);
+  if (serialno)
+    serialno_bin = hex_to_buffer (serialno, &serialno_bin_len);
+
+  err = select_application (ctrl, apptype, &ctrl->app_ctx, 1,
+                            serialno_bin, serialno_bin_len);
+  xfree (serialno_bin);
 
   return err;
 }
 
 
 static const char hlp_serialno[] =
-  "SERIALNO [<apptype>]\n"
+  "SERIALNO [--demand=<serialno>] [<apptype>]\n"
   "\n"
   "Return the serial number of the card using a status response.  This\n"
   "function should be used to check for the presence of a card.\n"
   "\n"
+  "If --demand is given, an application on the card with SERIALNO is\n"
+  "selected and an error is returned if no such card available.\n"
+  "\n"
   "If APPTYPE is given, an application of that type is selected and an\n"
   "error is returned if the application is not supported or available.\n"
   "The default is to auto-select the application using a hardwired\n"
@@ -245,17 +265,29 @@ cmd_serialno (assuan_context_t ctx, char *line)
   int rc = 0;
   char *serial;
   time_t stamp;
+  const char *demand;
 
-  /* Clear the remove flag so that the open_card is able to reread it.  */
-  if (ctrl->server_local->card_removed)
-    {
   if ( IS_LOCKED (ctrl) )
     return gpg_error (GPG_ERR_LOCKED);
 
-      ctrl->server_local->card_removed = 0;
+  if ((demand = has_option_name (line, "--demand")))
+    {
+      if (*demand != '=')
+        return set_error (GPG_ERR_ASS_PARAMETER, "missing value for option");
+      line = (char *)++demand;
+      for (; *line && !spacep (line); line++)
+        ;
+      if (*line)
+        *line++ = 0;
     }
+  else
+    demand = NULL;
 
-  if ((rc = open_card (ctrl, *line? line:NULL, 1)))
+  /* Clear the remove flag so that the open_card is able to reread it.  */
+  if (ctrl->server_local->card_removed)
+    ctrl->server_local->card_removed = 0;
+
+  if ((rc = open_card_with_request (ctrl, *line? line:NULL, demand)))
     {
       ctrl->server_local->card_removed = 1;
       return rc;
@@ -357,7 +389,7 @@ cmd_learn (assuan_context_t ctx, char *line)
   int rc = 0;
   int only_keypairinfo = has_option (line, "--keypairinfo");
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   /* Unless the force option is used we try a shortcut by identifying
@@ -440,7 +472,7 @@ cmd_readcert (assuan_context_t ctx, char *line)
   unsigned char *cert;
   size_t ncert;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   line = xstrdup (line); /* Need a copy of the line. */
@@ -482,7 +514,7 @@ cmd_readkey (assuan_context_t ctx, char *line)
   unsigned char *pk;
   size_t pklen;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (has_option (line, "--advanced"))
@@ -704,7 +736,7 @@ cmd_pksign (assuan_context_t ctx, char *line)
 
   line = skip_options (line);
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   /* We have to use a copy of the key ID because the function may use
@@ -748,7 +780,7 @@ cmd_pkauth (assuan_context_t ctx, char *line)
   size_t outdatalen;
   char *keyidstr;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -793,7 +825,7 @@ cmd_pkdecrypt (assuan_context_t ctx, char *line)
   char *keyidstr;
   unsigned int infoflags;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   keyidstr = xtrystrdup (line);
@@ -846,7 +878,7 @@ cmd_getattr (assuan_context_t ctx, char *line)
   int rc;
   const char *keyword;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   keyword = line;
@@ -888,7 +920,7 @@ cmd_setattr (assuan_context_t ctx, char *orig_line)
   size_t nbytes;
   char *line, *linebuf;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   /* We need to use a copy of LINE, because PIN_CB uses the same
@@ -943,7 +975,7 @@ cmd_writecert (assuan_context_t ctx, char *line)
     line++;
   *line = 0;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -1005,7 +1037,7 @@ cmd_writekey (assuan_context_t ctx, char *line)
     line++;
   *line = 0;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -1092,7 +1124,7 @@ cmd_genkey (assuan_context_t ctx, char *line)
     line++;
   *line = 0;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -1130,7 +1162,7 @@ cmd_random (assuan_context_t ctx, char *line)
                       "number of requested bytes missing");
   nbytes = strtoul (line, NULL, 0);
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -1183,7 +1215,7 @@ cmd_passwd (assuan_context_t ctx, char *line)
     line++;
   *line = 0;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -1240,7 +1272,7 @@ cmd_checkpin (assuan_context_t ctx, char *line)
   int rc;
   char *idstr;
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   if (!ctrl->app_ctx)
@@ -1531,7 +1563,7 @@ cmd_apdu (assuan_context_t ctx, char *line)
 
   line = skip_options (line);
 
-  if ((rc = open_card (ctrl, NULL, 0)))
+  if ((rc = open_card (ctrl)))
     return rc;
 
   app = ctrl->app_ctx;