3 # Netgear WNCE2001 has does a checksum check on boot and goes into recovery
4 # tftp mode when the check fails. Initializing the JFFS2 partition triggers
5 # this, so we make sure to zero checksum and size to be checksummed before
6 # that happens, so this needs to run very early during boot.
8 do_checksumming_disable() {
11 local board=$(ramips_board_name)
15 echo "Board is WNCE2001, updating checksum partition..."
16 local zeroes=/dev/zero
17 local tmpfile=/tmp/wnce2001_checksum
18 local partname=checksum
19 local mtd=$(find_mtd_part $partname)
20 dd if=$mtd of=$tmpfile bs=80 count=1 2>/dev/null
21 signature=$(dd if=$tmpfile bs=1 skip=24 count=20 2>/dev/null)
22 checksum=$(dd if=$tmpfile bs=1 count=4 2>/dev/null | hexdump -v -n 4 -e '1/1 "%02x"')
23 if [ "$signature" != "RT3052-AP-WNCE2001-3" ]; then
24 echo "Signature of checksum partition is wrong, bailing."
27 if [ "$checksum" != "00000000" ]; then
28 echo "Checksum is set, zeroing."
30 dd if=$zeroes of=$tmpfile conv=notrunc bs=1 seek=0 count=4 2>/dev/null
31 # zero out bytecount to be checksummed
32 dd if=$zeroes of=$tmpfile conv=notrunc bs=1 seek=60 count=4 2>/dev/null
33 mtd write $tmpfile $partname
35 echo "Checksum is already zero, nothing to do."
39 echo "Board is ASUS RT-N56U, replacing uImage header..."
40 local firmware_mtd=$(find_mtd_part firmware)
41 local rootfs_mtd=$(find_mtd_part rootfs)
42 local rootfs_data_mtd=$(find_mtd_part rootfs_data)
43 local rootfs_len=$(grep \"rootfs\" /proc/mtd | awk -F' ' '{print "0x"$2}')
44 local rootfs_data_len=$(grep \"rootfs_data\" /proc/mtd | awk -F' ' '{print "0x"$2}')
45 local offset=$(echo "$rootfs_len $rootfs_data_len 0x40" | awk -F' ' '{printf "%i",$1-$2-$3}')
46 local signature=$(dd if=$rootfs_mtd skip=$offset bs=1 count=4 2>/dev/null | hexdump -v -n 4 -e '1/1 "%02x"')
47 if [ "$signature" == "27051956" ]; then
48 dd conv=notrunc if=$rootfs_mtd skip=$offset of=$firmware_mtd bs=1 count=64 2>/dev/null
56 boot_hook_add preinit_main do_checksumming_disable