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Someone from the JammaForums.co.uk emailed me a copy of the firmware in their SD card from a XinYe 138 in 1.

Card looks something like this:

I don’t have one, but I took a quick look at the data provided, and it looks fairly straightforward to “hack”.

It actually took me less than 30 minutes to have most of the good bits extracted from receiving the file!

There are 2 files on the SD card.

One is a 64 byte file called sn.bin which contains this data:

This looks suspiciously like a header, but I haven’t taken a clear look.

The second file is called x3rodl.bin, and contains a Linux firmware in ARM format.

The first few hundred bytes look like this:

Its obviously in ARM format, as the first set of bytes are ARM no-op codes.

00 00 A0 E1, which repeats 8 times.
02 00 00 EA, then…
18 28 6F 01 – Which is a magic word indicating that this contains a zImage (compressed Linux kernel)

18 28 6F 01 = 0x016f2818

Linux code looks something like this for identifying if its a kernel:

if (*(ulong *)(to + 9*4) != LINUX_ZIMAGE_MAGIC) {
printk("Warning: this binary is not compressed linux kernel image/n");
printk("zImage magic = 0x%08lx/n", *(ulong *)(to + 9*4));
} else {
printk("zImage magic = 0x%08lx/n", *(ulong *)(to + 9*4));
}

9 * 4 = 36, which is our location, and this happens to have our magic number.
So, we know its a kernel. Its also probably the VIVI bootloader from Samsung, as that uses that style MAGIC.

The following bits of data, contain the setup for the kernel, and the boot code.

This continues on until the compressed kernel+ramdisk. That starts with 1F 8B 08 (gzip header bytes) over at 0x3EF2, until roughly the end of the file.

I extracted that part and had a quick look.
Its about 7.7M size unpacked.

Linux version is: 2.6.36-FriendlyARM

Boot params are:
console=ttySAC0,115200 root=/dev/ram init=/linuxrc initrd=0x51000000,6M ramdisk_size=6144

RAMDISK File System starts at 0x20000, and looks like this:

lawrence$ ls -al
total 24
drwxr-xr-x 13 lawrence staff 442 Jun 17 23:09 .
drwxr-xr-x 4 lawrence staff 136 Jun 17 23:08 ..
drwxr-xr-x 51 lawrence staff 1734 Jun 17 23:09 bin
drwxr-xr-x 2 lawrence staff 68 Jun 17 23:09 dev
drwxr-xr-x 11 lawrence staff 374 Jun 17 23:09 etc
-rwxr-xr-x 1 lawrence staff 3821 Jun 17 23:09 init
-rw-r--r-- 1 lawrence staff 3821 Jun 17 23:09 init~
lrwxrwxrwx 1 lawrence staff 11 Jun 17 23:09 linuxrc -> bin/busybox
drwxr-xr-x 2 lawrence staff 68 Jun 17 23:09 proc
drwxr-xr-x 2 lawrence staff 68 Jun 17 23:09 r
drwxr-xr-x 19 lawrence staff 646 Jun 17 23:09 sbin
drwxr-xr-x 2 lawrence staff 68 Jun 17 23:09 sdcard
drwxr-xr-x 4 lawrence staff 136 Jun 17 23:09 usr

The bootup script for this looks like this:


#! /bin/sh

PATH=/sbin:/bin:/usr/sbin:/usr/bin
runlevel=S
prevlevel=N
umask 022
export PATH runlevel prevlevel

echo st.

#
# Trap CTRL-C &c only in this shell so we can interrupt subprocesses.
#
trap ":" INT QUIT TSTP
/bin/hostname FriendlyARM
/bin/mount -n -t proc proc /proc

cmdline=`cat /proc/cmdline`

ROOT=none
ROOTFLAGS=
ROOTFSTYPE=
NFSROOT=
IP=
INIT=/sbin/init
#run_fs_image=/images/linux/rootfs_xin1arm_sdhotplug.ext3

for x in $cmdline ; do
case $x in
root=*)
ROOT=${x#root=}
;;
rootfstype=*)
ROOTFSTYPE="-t ${x#rootfstype=}"
;;
rootflags=*)
ROOTFLAGS="-o ${x#rootflags=}"
;;
init=*)
INIT=${x#init=}
;;
nfsroot=*)
NFSROOT=${x#nfsroot=}
;;
ip=*)
IP=${x#ip=}
;;

esac
done

if [ ! -z $NFSROOT ] ; then
echo $NFSROOT | sed s/:/\ /g > /dev/x ; read sip dir < /dev/x echo $IP | sed s/:/\ /g > /dev/x; read cip sip2 gip netmask hostname device autoconf < /dev/x rm /dev/x #echo $sip $dir $cip $sip2 $gip $netmask $hostname $device $autoconf mount -t nfs $NFSROOT /r -o nolock,proto=tcp #[ -e /r/dev/console ] || exec /bin/sh elif [ ! -z $run_fs_image ] ; then #lilxc #echo $run_fs_image echo sdroot. if [ ! -e /dev/mmcblk0p2 ] ; then echo "p2 not found." reboot sleep 5 fi ROOTFSTYPE="-t ext3" for i in 1 2 3 4 5 ; do #/bin/mount -n -o sync -o noatime -o nodiratime -o ro -t vfat /dev/mmcblk0p1 /sdcard && break /bin/mount -n -o sync -o noatime -o nodiratime -o ro -t ext3 /dev/mmcblk0p2 /sdcard && break echo Waiting for SD Card... if [ $i = 4 ] ; then echo " p2 failed. " reboot sleep 5 break; fi sleep 1 done #echo ------begin---------------------------------------- #sleep 1 #lilxc #ls -l /dev #sleep 1 #echo ----------------------------------------------- #ls -l /sdcard #sleep 1 #echo ------end------------------------------------------ #/sbin/losetup /dev/loop0 /sdcard/$run_fs_image #/bin/mount $ROOTFSTYPE /dev/loop0 /r #/bin/mount $ROOTFSTYPE -o noatime -o nodiratime -o ro /dev/mmcblk0p2 /r > /dev/null 2>&1
/bin/mount $ROOTFSTYPE -n -o noatime -o nodiratime -o ro /dev/mmcblk0p3 /r > /dev/null 2>&1
mount -o move /sdcard /r/sdcard
#/sbin/losetup /dev/loop1 /r/sdcard/swap
#/sbin/swapon /dev/loop1

else
# /bin/mount -n $ROOTFLAGS $ROOTFSTYPE $ROOT /r
# echo "Readonly mount...(lilxc)"
# mount -n -t yaffs2 -o noatime -o nodiratime -o ro /dev/mtdblock2 /r
# mount -n -t yaffs2 -o noatime -o nodiratime /dev/mtdblock2 /r

mount -n -t yaffs2 -o noatime -o nodiratime -o ro /dev/mtdblock2 /r

if [ -e /r/home/plg/reboot ]; then
umount /r
mount -n -t yaffs2 -o noatime -o nodiratime /dev/mtdblock2 /r
fi

fi

ONE_WIRE_PROC=/proc/driver/one-wire-info
ETC_BASE=/r/etc
[ -d /r/system/etc ] && ETC_BASE=/r/system/etc
[ -e $ETC_BASE/ts.detected ] && . $ETC_BASE/ts.detected
[ -z $CHECK_1WIRE ] && CHECK_1WIRE=Y
if [ $CHECK_1WIRE = "Y" -a -e $ONE_WIRE_PROC ] ; then
if read lcd_type fw_ver tail < $ONE_WIRE_PROC ; then if [ x$lcd_type = "x0" -a x$fw_ver = "x0" ] ; then TS_DEV=/dev/touchscreen else TS_DEV=/dev/touchscreen-1wire echo "1Wire touchscreen OK" fi if [ -e $ETC_BASE/friendlyarm-ts-input.conf ]; then sed "s:^\(TSLIB_TSDEVICE=\).*:\1$TS_DEV:g" $ETC_BASE/friendlyarm-ts-input.conf > $ETC_BASE/ts-autodetect.conf
mv $ETC_BASE/ts-autodetect.conf $ETC_BASE/friendlyarm-ts-input.conf -f
echo "CHECK_1WIRE=N" > $ETC_BASE/ts.detected
fi
fi
fi

[ -e /r/etc/friendlyarm-ts-input.conf ] && . /r/etc/friendlyarm-ts-input.conf
[ -e /r/system/etc/friendlyarm-ts-input.conf ] && . /r/system/etc/friendlyarm-ts-input.conf
export TSLIB_TSDEVICE

#lilxc debug here
#/bin/mount -n -o sync -o noatime -o nodiratime -t vfat /dev/mmcblk0p1 /sdcard
#cp /sdcard/lktcmd /r/tmp
#exec /bin/sh

# for running game
umount /proc
exec switch_root /r $INIT /r/dev/console 2>&1

The secondary loader in init looks like this:

#! /bin/sh

PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin:
runlevel=S
prevlevel=N
umask 022
export PATH runlevel prevlevel

#
# Trap CTRL-C &c only in this shell so we can interrupt subprocesses.
#
trap ":" INT QUIT TSTP
/bin/hostname FriendlyARM

[ -e /proc/1 ] || /bin/mount -n -t proc none /proc
[ -e /sys/class ] || /bin/mount -n -t sysfs none /sys
[ -e /dev/tty ] || /bin/mount -t ramfs none /dev
/bin/mount -n -t usbfs none /proc/bus/usb

echo /sbin/mdev > /proc/sys/kernel/hotplug
/sbin/mdev -s
/bin/hotplug
# mounting file system specified in /etc/fstab
mkdir -p /dev/pts
mkdir -p /dev/shm
/bin/mount -n -t devpts none /dev/pts -o mode=0622
/bin/mount -n -t tmpfs tmpfs /dev/shm
/bin/mount -n -t ramfs none /tmp
/bin/mount -n -t ramfs none /var
mkdir -p /var/empty
mkdir -p /var/log
mkdir -p /var/lock
mkdir -p /var/run
mkdir -p /var/tmp

/sbin/hwclock -s

echo " " > /dev/tty1
echo "System starting... " > /dev/tty1
syslogd

#/etc/rc.d/init.d/netd start
#echo " " > /dev/tty1
#echo "Starting networking..." > /dev/tty1
#sleep 1
#/etc/rc.d/init.d/httpd start
#echo " " > /dev/tty1
#echo "Starting web server..." > /dev/tty1
#sleep 1
#/etc/rc.d/init.d/leds start
#echo " " > /dev/tty1
#echo "Starting leds service..." > /dev/tty1
#echo " "
#sleep 1

/etc/rc.d/init.d/mkjoy
#echo " " > /dev/tty1
#echo "System Starting... " > /dev/tty1
#echo " " > /dev/tty1

#echo " " > /dev/tty1
/etc/rc.d/init.d/alsaconf start
#echo "Loading sound card config..." > /dev/tty1
#echo " "

#/sbin/ifconfig lo 127.0.0.1
#/etc/init.d/ifconfig-eth0

#/bin/qtopia &
#echo " " > /dev/tty1
#echo "Starting Qtopia, please waiting..." > /dev/tty1

cd /sdcard
./run.sh
reboot

Fairly easy to reverse!

Refs:
http://www.jammaplus.co.uk/
http://blog.csdn.net/liangkaiming/article/details/6259189