initrd/bin/seal-hotpkey: Show error if /boot can't be mounted

If we can't mount /boot, show a meaningful error rather than dropping
to a recovery shell.

Dropping to a recovery shell should be a last resort.  Users that know
how to use the recovery shell know how to get there.  Users that don't
know how to use it can be completely stuck and may not know how to get
back to the menu or even how to turn off the device.

Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>

initrd/bin/seal-hotpkey

@@ -11,9 +11,12 @@ mount_boot()
 {
   TRACE "Under /bin/seal-hotpkey:mount_boot"
   # Mount local disk if it is not already mounted
-  if ! grep -q /boot /proc/mounts ; then
-    mount -o ro /boot \
-      || recovery "Unable to mount /boot"
+  if ! grep -q /boot /proc/mounts; then
+    if ! mount -o ro /boot; then
+      whiptail $BG_COLOR_ERROR --title 'ERROR' \
+        --msgbox "Couldn't mount /boot.\n\nCheck the /boot device in configuration settings, or perform an OEM reset." 0 80
+      return 1
+    fi
   fi
 }
 
@@ -45,7 +48,7 @@ fi
 # Store counter in file instead of TPM for now, as it conflicts with Heads
 # config TPM counter as TPM 1.2 can only increment one counter between reboots
 # get current value of HOTP counter in TPM, create if absent
-mount_boot
+mount_boot || exit 1
 
 #check_tpm_counter $HOTP_COUNTER hotp \
 #|| die "Unable to find/create TPM counter"