From bc55deab2a08e7fda7bcd3ae0ecc88e1e7d3d76e Mon Sep 17 00:00:00 2001
From: Benjamin Berg <bberg@redhat.com>
Date: Wed, 16 Dec 2020 15:41:31 +0100
Subject: [PATCH] device: Do not allow enrolling a finger that is already
 enrolled

This makes little sense. Users should delete the finger before trying to
enroll the same one again. So throw an error at them from EnrollStart
right away.

Fixes: #95
---
 src/device.c   | 16 ++++++++++++++++
 src/device.xml |  1 +
 src/fprintd.h  |  2 ++
 3 files changed, 19 insertions(+)

diff --git a/src/device.c b/src/device.c
index 53668d6..e3f4cd8 100644
--- a/src/device.c
+++ b/src/device.c
@@ -1944,6 +1944,8 @@ fprint_device_enroll_start (FprintDBusDevice      *dbus_dev,
                             const char            *finger_name)
 {
   g_autoptr(GError) error = NULL;
+  g_autoptr(FpPrint) existing_print = NULL;
+  g_autoptr(SessionData) session = NULL;
   FprintDevice *rdev = FPRINT_DEVICE (dbus_dev);
   FprintDevicePrivate *priv = fprint_device_get_instance_private (rdev);
   FpFinger finger = finger_name_to_fp_finger (finger_name);
@@ -1962,6 +1964,20 @@ fprint_device_enroll_start (FprintDBusDevice      *dbus_dev,
       return TRUE;
     }
 
+  session = session_data_get (priv);
+  store.print_data_load (priv->dev, finger,
+                         session->username, &existing_print);
+
+  if (existing_print)
+    {
+      g_set_error (&error, FPRINT_ERROR, FPRINT_ERROR_FINGER_ALREADY_ENROLLED,
+                   "Finger %d has already been enrolled for user %s", finger, session->username);
+      g_dbus_method_invocation_return_gerror (invocation,
+                                              error);
+      return TRUE;
+    }
+
+
   if (!can_start_action (rdev, &error))
     {
       g_dbus_method_invocation_return_gerror (invocation, error);
diff --git a/src/device.xml b/src/device.xml
index 362ee97..a3c1dbe 100644
--- a/src/device.xml
+++ b/src/device.xml
@@ -525,6 +525,7 @@
 					<doc:error name="&ERROR_CLAIM_DEVICE;">if the device was not claimed</doc:error>
 					<doc:error name="&ERROR_ALREADY_IN_USE;">if the device was already being used</doc:error>
 					<doc:error name="&ERROR_INVALID_FINGERNAME;">if the finger name passed is invalid</doc:error>
+					<doc:error name="&FINGER_ALREADY_ENROLLED;">if the finger has been already enrolled by the user</doc:error>
 					<doc:error name="&ERROR_INTERNAL;">if there was an internal error</doc:error>
 				</doc:errors>
 
diff --git a/src/fprintd.h b/src/fprintd.h
index 1fd6d70..d6233a9 100644
--- a/src/fprintd.h
+++ b/src/fprintd.h
@@ -45,6 +45,8 @@ typedef enum {
   FPRINT_ERROR_PERMISSION_DENIED,       /*< nick=net.reactivated.Fprint.Error.PermissionDenied >*/
   /* No prints are enrolled */
   FPRINT_ERROR_NO_ENROLLED_PRINTS,       /*< nick=net.reactivated.Fprint.Error.NoEnrolledPrints >*/
+  /* Prints has already been enrolled */
+  FPRINT_ERROR_FINGER_ALREADY_ENROLLED,  /*< nick=net.reactivated.Fprint.Error.FingerAlreadyEnrolled >*/
   /* No actions currently in progress */
   FPRINT_ERROR_NO_ACTION_IN_PROGRESS,       /*< nick=net.reactivated.Fprint.Error.NoActionInProgress >*/
   /* the finger name passed was invalid */