1 files changed, 85 insertions, 0 deletions
diff --git a/files/initramfs/expand_encrypted_rootfs b/files/initramfs/expand_encrypted_rootfs
new file mode 100644
index 0000000..e6896ba
--- /dev/null
+++ b/files/initramfs/expand_encrypted_rootfs
@@ -0,0 +1,85 @@
+#!/bin/sh
+# expand_encrypted_rootfs initramfs-tools boot script
+
+# dependencies: grep awk cut tail fdisk parted e2fsck resize2fs
+
+set -e
+
+# Wait for USB devices to be ready
+sleep 5
+
+# Use initramfs utility functions
+if [ -r "/scripts/functions" ] ; then
+  . /scripts/functions
+fi
+
+# Check for cryptdevice variable
+if [ -z "$cryptdevice" ] ; then
+  echo "unable to get cryptdevice variable (init-premount)"
+  return 1
+fi
+
+# Detect root partition device
+ROOT_PART=$(echo $cryptdevice | awk -F"/|:" '{ print $3 }')
+if [ -z "$ROOT_PART" ] ; then
+  log_warning_msg "unable to detect encrypted root partition device (cryptdevice)"
+  return 1
+fi
+
+# Extract root device name
+case "${ROOT_PART}" in
+  mmcblk0*) ROOT_DEV=mmcblk0 ;;
+  sda*)     ROOT_DEV=sda ;;
+esac
+
+# Check detected root partition name
+PART_NUM=$(echo ${ROOT_PART} | grep -o '[1-9][0-9]*$')
+if [ "$PART_NUM" = "$ROOT_PART" ] ; then
+  log_warning_msg "$ROOT_PART is not an SD card. Don't know how to expand"
+  return 1
+fi
+
+# NOTE: the NOOBS partition layout confuses parted. For now, let's only
+# agree to work with a sufficiently simple partition layout
+if [ "$PART_NUM" -gt 2 ] ; then
+  log_warning_msg "Your partition layout is not currently supported by this tool."
+  return 1
+fi
+
+# Check if last partition number
+LAST_PART_NUM=$(parted /dev/${ROOT_DEV} -ms unit s p | tail -n 1 | cut -f 1 -d:)
+if [ $LAST_PART_NUM -ne $PART_NUM ]; then
+  log_warning_msg "$ROOT_PART is not the last partition. Don't know how to expand"
+  return 1
+fi
+
+# Get the starting offset of the root partition
+PART_START=$(parted /dev/${ROOT_DEV} -ms unit s p | grep "^${PART_NUM}" | cut -f 2 -d: | sed 's/[^0-9]//g')
+if [ -z "$PART_START" ] ; then
+  log_warning_msg "${ROOT_DEV} unable to get starting sector of the partition"
+  return 1
+fi
+
+# Get the possible last sector for the root partition
+PART_LAST=$(fdisk -l /dev/${ROOT_DEV} | grep '^Disk.*sectors' | awk '{ print $7 - 1 }')
+if [ -z "$PART_LAST" ] ; then
+  log_warning_msg "${ROOT_DEV} unable to get last sector of the partition"
+  return 1
+fi
+
+### Since rc.local is run with "sh -e", let's add "|| true" to prevent premature exit
+fdisk /dev/${ROOT_DEV} 2> /dev/null <<EOF2 || true
+p
+d
+$PART_NUM
+n
+p
+$PART_NUM
+$PART_START
+$PART_LAST
+p
+w
+EOF2
+
+partprobe
+log_success_msg "Root partition successfully resized."