--- cryptroot.orig	2022-05-21 12:59:09.224162975 +0200
+++ usr/share/initramfs-tools/scripts/local-top/cryptroot	2022-04-23 19:58:19.872003766 +0200
@@ -1,5 +1,7 @@
 #!/bin/sh
 
+# Search for cryptkey.txt
+
 PREREQ="cryptroot-prepare"
 
 #
@@ -159,8 +161,48 @@
             # unlock via keyfile
             unlock_mapping "$CRYPTTAB_KEY"
         else
-            # unlock interactively or via keyscript
-            run_keyscript "$count" | unlock_mapping
+	    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
+		    echo -n " $partition"
+		    if mount -oro /dev/"$partition" /mnt 2>/dev/null; then
+			echo -n "(mounted)"
+			cat /mnt/cryptkey.txt >> /tmp/cryptkeys.txt 2>/dev/null
+			umount /dev/"$partition"
+		    fi
+		done
+		echo "done."
+	    fi
+    
+	    if [ -s /tmp/cryptkeys.txt ]; then
+		local keyfound
+                keyfound=0
+                echo "Trying keys from cryptkey.txt for opening $CRYPTTAB_SOURCE as $CRYPTTAB_NAME"
+                for key in `cat /tmp/cryptkeys.txt`; do
+                    if echo -n "$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 ))