OpenWrt – Rev 1

Subversion Repositories:
Rev:
#!/bin/sh

# Netgear WNCE2001 has does a checksum check on boot and goes into recovery
# tftp mode when the check fails.  Initializing the JFFS2 partition triggers
# this, so we make sure to zero checksum and size to be checksummed before
# that happens, so this needs to run very early during boot.

do_checksumming_disable() {
        . /lib/functions.sh

        local board=$(board_name)

        case "$board" in
        wnce2001)
                echo "Board is WNCE2001, updating checksum partition..."
                local zeroes=/dev/zero
                local tmpfile=/tmp/wnce2001_checksum
                local partname=checksum
                local mtd=$(find_mtd_part $partname)
                dd if=$mtd of=$tmpfile bs=80 count=1 2>/dev/null
                signature=$(dd if=$tmpfile bs=1 skip=24 count=20 2>/dev/null)
                checksum=$(dd if=$tmpfile bs=1 count=4 2>/dev/null | hexdump -v -n 4 -e '1/1 "%02x"')
                if [ "$signature" != "RT3052-AP-WNCE2001-3" ]; then
                        echo "Signature of checksum partition is wrong, bailing."
                        return 0
                fi
                if [ "$checksum" != "00000000" ]; then
                        echo "Checksum is set, zeroing."
                        # zero out checksum
                        dd if=$zeroes of=$tmpfile conv=notrunc bs=1 seek=0 count=4 2>/dev/null
                        # zero out bytecount to be checksummed
                        dd if=$zeroes of=$tmpfile conv=notrunc bs=1 seek=60 count=4 2>/dev/null
                        mtd write $tmpfile $partname
                else
                        echo "Checksum is already zero, nothing to do."
                fi
        ;;
        rt-n56u)
                echo "Board is ASUS RT-N56U, replacing uImage header..."
                local firmware_mtd=$(find_mtd_part firmware)
                local rootfs_mtd=$(find_mtd_part rootfs)
                local rootfs_data_mtd=$(find_mtd_part rootfs_data)
                local rootfs_len=$(grep \"rootfs\" /proc/mtd | awk -F' ' '{print "0x"$2}')
                local rootfs_data_len=$(grep \"rootfs_data\" /proc/mtd | awk -F' ' '{print "0x"$2}')
                local offset=$(echo "$rootfs_len $rootfs_data_len 0x40" | awk -F' ' '{printf "%i",$1-$2-$3}')
                local signature=$(dd if=$rootfs_mtd skip=$offset bs=1 count=4 2>/dev/null | hexdump -v -n 4 -e '1/1 "%02x"')
                if [ "$signature" = "27051956" ]; then
                        dd conv=notrunc if=$rootfs_mtd skip=$offset of=$firmware_mtd bs=1 count=64 2>/dev/null
                fi
        ;;
        esac

        return 0
}

boot_hook_add preinit_main do_checksumming_disable