--- /usr/share/initramfs-tools/scripts/local-top/cryptroot.orig	2020-05-03 01:25:43.388812582 +0200
+++ /usr/share/initramfs-tools/scripts/local-top/cryptroot	2020-05-03 01:25:43.392812547 +0200
@@ -123,6 +123,23 @@
         fi
     fi
 
+    if [ -z "${CRYPTTAB_OPTION_keyscript+x}" ]; then
+       # Wait for USB to settle
+       /bin/sleep 3
+
+       # Test all devices
+       mkdir /mnt
+       echo -n "Searching for cryptkey.txt on available disks... "
+       local partition
+       for partition in `cat /proc/partitions |awk '{print $4}'|tail -n +3`; do
+           if mount /dev/$partition /mnt 2>/dev/null; then
+               cat /mnt/cryptkey.txt >> /tmp/cryptkeys.txt 2>/dev/null
+               umount /dev/$partition
+           fi
+       done
+       echo "done."
+    fi
+    
     get_crypt_type # set CRYPTTAB_TYPE to the type of crypt device
     local count=0 maxtries="${CRYPTTAB_OPTION_tries:-3}" fstype vg rv
     while [ $maxtries -le 0 ] || [ $count -lt $maxtries ]; do
@@ -130,8 +147,29 @@
             # unlock via keyfile
             unlock_mapping "$CRYPTTAB_KEY"
         else
-            # unlock interactively or via keyscript
-            run_keyscript "$CRYPTTAB_KEY" "$count" | unlock_mapping
+	    if [ -s /tmp/cryptkeys.txt ]; then
+		local keyfound
+                keyfound=0
+                echo Trying keys from cryptkey.txt
+                for key in `cat /tmp/cryptkeys.txt`; do
+                    if echo -n "$key" | unlock_mapping; then
+                        # Found the key
+                        echo Key found in cryptkey.txt
+                        keyfound=1
+                        key=""
+                    fi
+                done
+                # Remove traces of the key
+                rm /tmp/cryptkeys.txt
+                unset key
+		if [ "$keyfound" = "0" ]; then
+                    # Fall back to manual entry
+		    run_keyscript "$CRYPTTAB_KEY" "$count" | unlock_mapping
+		fi
+	    else
+		# unlock interactively or via keyscript
+		run_keyscript "$CRYPTTAB_KEY" "$count" | unlock_mapping
+	    fi
         fi
         rv=$?
         count=$(( $count + 1 ))