Firmware hacking: Jcnip M218B #1

Tuesday, February 22, 2011

$ wget http://www.jcnip.com/m218aupdata/M218B056firmware.rar

$ unrar-nonfree x M218B056firmware.rar 

UNRAR 4.00 beta 3 freeware      Copyright (c) 1993-2010 Alexander Roshal

Extracting from M218B056firmware.rar

Creating    firmware                                                  OK

Extracting  firmware/M218B-v0.56.bin                                  OK 

Creating    reflash_nor                                               OK

Extracting  reflash_nor/md5sum_32                                     OK 

Extracting  reflash_nor/md5sum_64                                     OK 

Extracting  reflash_nor/mtd032                                        OK 

Extracting  reflash_nor/mtd064                                        OK 

Extracting  reflash_nor/mtd1                                          OK 

Extracting  reflash_nor/mtd2                                          OK 

Extracting  reflash_nor/upgrade.sh                                    OK 

All OK

$ cat reflash_nor/upgrade.sh 

#!/bin/sh

REFLASH_NOR=/mnt/sd1/reflash_nor

PKERNEL=mtd1

ROOTFS=mtd2

BOOTLOADER_DEST=/dev/mtdblock0

PKERNEL_DEST=/dev/mtdblock1

ROOTFS_DEST=/dev/mtdblock2

MEM_SIZE=`cat /proc/cmdline  | cut -d '=' -f3 | cut -d ' ' -f1`

test $MEM_SIZE = "32M" && BOOTLOADER=mtd032

test $MEM_SIZE = "64M" && BOOTLOADER=mtd064

echo "Upgrading Bootloader"

dd "if=$REFLASH_NOR/$BOOTLOADER" "of=$BOOTLOADER_DEST"

echo "Upgrading P-Kernel"

dd "if=$REFLASH_NOR/$PKERNEL" "of=$PKERNEL_DEST"

echo "Upgrading Pminiroot"

dd "if=$REFLASH_NOR/$ROOTFS" "of=$ROOTFS_DEST"

echo "done"

Firmware hacking