verify: Fail if we try to verify a non-enrolled finger

Since we list the fingers available fail early in case it's not found

tests/test_fprintd_utils.py

@@ -22,6 +22,20 @@ import fcntl
 import os
 import time
 
+
+VALID_FINGER_NAMES = [
+    'left-thumb',
+    'left-index-finger',
+    'left-middle-finger',
+    'left-ring-finger',
+    'left-little-finger',
+    'right-thumb',
+    'right-index-finger',
+    'right-middle-finger',
+    'right-ring-finger',
+    'right-little-finger'
+]
+
 dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
 
 class TestFprintdUtilsBase(dbusmock.DBusTestCase):
@@ -181,6 +195,10 @@ class TestFprintdUtilsVerify(TestFprintdUtilsBase):
         self.assertNotRegex(out, r'Device already in use by [A-z]+')
         self.assertNotIn('Verify result:', out)
 
+        if checkEnrolled and finger:
+            self.assertNotIn('''Finger '{}' not enrolled for user {}'''.format(
+                finger, user), out)
+
         if checkEnrolled:
             for f in self.enrolled_fingers:
                 self.assertIn(f, out)
@@ -205,6 +223,13 @@ class TestFprintdUtilsVerify(TestFprintdUtilsBase):
             time.sleep(self.sleep_time)
             self.assertVerifyMatch(True)
 
+    def test_fprintd_verify_not_enrolled_fingers(self):
+        for finger in [f for f in VALID_FINGER_NAMES if f not in self.enrolled_fingers]:
+            regex = r'Finger \'{}\' not enrolled'.format(finger)
+            with self.assertRaisesRegex(AssertionError, regex):
+                self.start_verify_process(finger=finger)
+            self.device_mock.Release()
+
     def test_fprintd_verify_script(self):
         script = [
             ( 'verify-match', True, 2 )

utils/verify.c

@@ -100,6 +100,14 @@ static void find_finger(DBusGProxy *dev, const char *username)
 		g_print(" - #%d: %s\n", i, fingers[i]);
 	}
 
+	if (finger_name && !g_str_equal (finger_name, "any") &&
+	    !g_strv_contains ((const char **) fingers, finger_name)) {
+		g_print("Finger '%s' not enrolled for user %s.\n", finger_name,
+		        username);
+		g_free (finger_name);
+		exit(1);
+	}
+
 	if (finger_name == NULL || strcmp (finger_name, "any") == 0) {
 		g_free (finger_name);
 		finger_name = g_strdup (fingers[0]);