#!/bin/bash
set -e

# This is the Raspberry Pi Kali 0-W Nexmon ARM build script - http://www.kali.org/downloads
# A trusted Kali Linux image created by Offensive Security - http://www.offensive-security.com
# Maintained by @binkybear

if [[ $EUID -ne 0 ]]; then
   echo "This script must be run as root"
   exit 1
fi

if [[ $# -eq 0 ]] ; then
    echo "Please pass version number, e.g. $0 2.0"
    exit 0
fi

basedir=`pwd`/rpi0w-nexmon-p4wnp1-$1
TOPDIR=`pwd`

# Custom hostname variable
hostname=${2:-kali}
# Custom image name variable - MUST NOT include .img at the end.
imagename=${3:-kali-linux-$1-rpi0w-nexmon-p4wnp1}
# Size of image in megabytes (Default is 7000=7GB)
size=7000

# Generate a random machine name to be used.
machine=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 16 | head -n 1)

# Package installations for various sections.
# This will build a minimal XFCE Kali system with the top 10 tools.
# This is the section to edit if you would like to add more packages.
# See http://www.kali.org/new/kali-linux-metapackages/ for meta packages you can
# use. You can also install packages, using just the package name, but keep in
# mind that not all packages work on ARM! If you specify one of those, the
# script will throw an error, but will still continue on, and create an unusable
# image, keep that in mind.

arm="abootimg cgpt fake-hwclock ntpdate vboot-utils vboot-kernel-utils u-boot-tools"
base="kali-menu kali-defaults initramfs-tools sudo parted e2fsprogs usbutils firmware-linux firmware-realtek firmware-atheros firmware-libertas"
#desktop="fonts-croscore fonts-crosextra-caladea fonts-crosextra-carlito gnome-theme-kali gtk3-engines-xfce kali-desktop-xfce kali-root-login lightdm network-manager network-manager-gnome xfce4 xserver-xorg-video-fbdev xserver-xorg-input-evdev xserver-xorg-input-synaptics"
tools="passing-the-hash winexe aircrack-ng hydra john sqlmap libnfc-bin mfoc nmap ethtool usbutils net-tools curl"
services="openssh-server apache2"
extras=" wpasupplicant python-smbus i2c-tools python-requests python-configobj python-pip bluez bluez-firmware"
# kernel sauces take up space
size=7000 # Size of image in megabytes

packages="${arm} ${base} ${tools} ${services} ${extras}"
architecture="armel"
# If you have your own preferred mirrors, set them here.
# After generating the rootfs, we set the sources.list to the default settings.
mirror=http.kali.org

# Check to ensure that the architecture is set to ARMEL since the RPi is the
# only board that is armel.
if [[ ${architecture} != "armel" ]] ; then
    echo "The Raspberry Pi cannot run Debian armhf binaries"
    exit 0
fi

# Set this to use an http proxy, like apt-cacher-ng, and uncomment further down
# to unset it.
#export http_proxy="http://localhost:3142/"

mkdir -p ${basedir}
cd ${basedir}

# create the rootfs - not much to modify here, except maybe the hostname.
debootstrap --foreign --arch ${architecture} kali-rolling kali-${architecture} http://${mirror}/kali

cp /usr/bin/qemu-arm-static kali-${architecture}/usr/bin/

LANG=C systemd-nspawn -M ${machine} -D kali-${architecture} /debootstrap/debootstrap --second-stage

cat << EOF > kali-${architecture}/etc/apt/sources.list
deb http://${mirror}/kali kali-rolling main contrib non-free
EOF

# Set hostname
echo "${hostname}" > kali-${architecture}/etc/hostname

# So X doesn't complain, we add $hostname to hosts
cat << EOF > kali-${architecture}/etc/hosts
127.0.0.1       ${hostname}    localhost
::1             localhost ip6-localhost ip6-loopback
fe00::0         ip6-localnet
ff00::0         ip6-mcastprefix
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters
EOF

cat << EOF > kali-${architecture}/etc/network/interfaces
auto lo
iface lo inet loopback
EOF

cat << EOF > kali-${architecture}/etc/resolv.conf
nameserver 8.8.8.8
EOF

export MALLOC_CHECK_=0 # workaround for LP: #520465
export LC_ALL=C
export DEBIAN_FRONTEND=noninteractive

#mount -t proc proc kali-$architecture/proc
#mount -o bind /dev/ kali-$architecture/dev/
#mount -o bind /dev/pts kali-$architecture/dev/pts

cat << EOF > kali-${architecture}/debconf.set
console-common console-data/keymap/policy select Select keymap from full list
console-common console-data/keymap/full select en-latin1-nodeadkeys
EOF

# Create monitor mode start/remove
cat << EOF > kali-${architecture}/usr/bin/monstart
#!/bin/bash
echo "Nexutil setting monitoring mode"
/usr/bin/nexutil -m2
EOF
chmod 755 kali-${architecture}/usr/bin/monstart

cat << EOF > kali-${architecture}/usr/bin/monstop
#!/bin/bash
/usr/bin/nexutil -m0
echo "Monitor mode stopped"
EOF
chmod 755 kali-${architecture}/usr/bin/monstop

cat << 'EOF' > kali-${architecture}/lib/systemd/system/regenerate_ssh_host_keys.service
[Unit]
Description=Regenerate SSH host keys
Before=ssh.service
[Service]
Type=oneshot
ExecStartPre=-/bin/dd if=/dev/hwrng of=/dev/urandom count=1 bs=4096
ExecStartPre=-/bin/sh -c "/bin/rm -f -v /etc/ssh/ssh_host_*_key*"
ExecStart=/usr/bin/ssh-keygen -A -v
ExecStartPost=/bin/sh -c "for i in /etc/ssh/ssh_host_*_key*; do actualsize=$(wc -c <\"$i\") ;if [ $actualsize -eq 0 ]; then echo size is 0 bytes ; exit 1 ; fi ; done ; /bin/systemctl disable regenerate_ssh_host_keys"
[Install]
WantedBy=multi-user.target
EOF
chmod 644 kali-${architecture}/lib/systemd/system/regenerate_ssh_host_keys.service

cat << EOF > kali-${architecture}/lib/systemd/system/rpiwiggle.service
[Unit]
Description=Resize filesystem
Before=regenerate_ssh_host_keys.service
[Service]
Type=oneshot
ExecStart=/root/scripts/rpi-wiggle.sh
ExecStartPost=/bin/systemctl disable rpiwiggle
ExecStartPost=/sbin/reboot
[Install]
WantedBy=multi-user.target
EOF
chmod 644 kali-${architecture}/lib/systemd/system/rpiwiggle.service

# Bluetooth enabling
mkdir -p kali-${architecture}/etc/udev/rules.d
cp ${basedir}/../misc/pi-bluetooth/99-com.rules kali-${architecture}/etc/udev/rules.d/99-com.rules
mkdir -p kali-${architecture}/lib/systemd/system/
cp ${basedir}/../misc/pi-bluetooth/hciuart.service kali-${architecture}/lib/systemd/system/hciuart.service
mkdir -p kali-${architecture}/lib/udev/rules.d/
cp ${basedir}/../misc/pi-bluetooth/50-bluetooth-hci-auto-poweron.rules kali-${architecture}/lib/udev/rules.d/50-bluetooth-hci-auto-poweron.rules
mkdir -p kali-${architecture}/usr/bin
cp ${basedir}/../misc/pi-bluetooth/btuart kali-${architecture}/usr/bin/btuart
cp ${basedir}/../misc/pi-bluetooth/pi-bluetooth_0.1.4+re4son_all.deb kali-${architecture}/root/pi-bluetooth_0.1.4+re4son_all.deb
# Ensure btuart is executable
chmod 755 kali-${architecture}/usr/bin/btuart

cat << EOF > kali-${architecture}/third-stage
#!/bin/bash
dpkg-divert --add --local --divert /usr/sbin/invoke-rc.d.chroot --rename /usr/sbin/invoke-rc.d
cp /bin/true /usr/sbin/invoke-rc.d
echo -e "#!/bin/sh\nexit 101" > /usr/sbin/policy-rc.d
chmod 755 /usr/sbin/policy-rc.d

apt-get update
apt-get --yes --allow-change-held-packages install locales-all

debconf-set-selections /debconf.set
rm -f /debconf.set
apt-get update
apt-get -y install git-core binutils ca-certificates initramfs-tools u-boot-tools
apt-get -y install locales console-common less nano git
echo "root:toor" | chpasswd
rm -f /etc/udev/rules.d/70-persistent-net.rules
export DEBIAN_FRONTEND=noninteractive
apt-get --yes --allow-change-held-packages install ${packages}
if [[ $? > 0 ]];
then
    apt-get --yes --allow-change-held-packages --fix-broken install
fi
apt-get --yes --allow-change-held-packages dist-upgrade
apt-get --yes --allow-change-held-packages autoremove



# Because copying in authorized_keys is hard for people to do, let's make the
# image insecure and enable root login with a password.

echo "Making the image insecure"
sed -i -e 's/^#PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config

# Resize FS on first run (hopefully)
systemctl enable rpiwiggle

# Generate SSH host keys on first run
systemctl enable regenerate_ssh_host_keys
systemctl enable ssh

# Install and hold pi-bluetooth deb package from re4son
dpkg --force-all -i /root/pi-bluetooth_0.1.4+re4son_all.deb
apt-mark hold pi-bluetooth

# systemd version 232 and above breaks execution of above bluetooth rule, let's fix that
sed -i 's/^RestrictAddressFamilies=AF_UNIX AF_NETLINK AF_INET AF_INET6.*/RestrictAddressFamilies=AF_UNIX AF_NETLINK AF_INET AF_INET6 AF_BLUETOOTH/' /lib/systemd/system/systemd-udevd.service

# Enable bluetooth
systemctl unmask bluetooth.service
systemctl enable bluetooth
systemctl enable hciuart

# Install P4wnP1 (kali version)
cd /root
git clone https://github.com/nethunteros/P4wnP1.git /root/P4wnP1
chmod 755 /root/P4wnP1/install.sh
cd /root/P4wnP1 
git submodule init
git submodule update --recursive --remote && 
./install.sh

echo "dwc2" | sudo tee -a /etc/modules
echo "libcomposite" | sudo tee -a /etc/modules

# Turn off kernel dmesg showing up in console since rpi0 only uses console
echo "dmesg -D" > /etc/rc.local
echo "exit 0" >> /etc/rc.local

# Copy bashrc
cp  /etc/bash.bashrc /root/.bashrc

# libinput seems to fail hard on RaspberryPi devices, so we make sure it's not
# installed here (and we have xserver-xorg-input-evdev and
# xserver-xorg-input-synaptics packages installed above!)
apt-get --yes --allow-change-held-packages purge xserver-xorg-input-libinput

rm -f /usr/sbin/policy-rc.d
rm -f /usr/sbin/invoke-rc.d
dpkg-divert --remove --rename /usr/sbin/invoke-rc.d

rm -f /third-stage
EOF

chmod 755 kali-${architecture}/third-stage
LANG=C systemd-nspawn -M ${machine} -D kali-${architecture} /third-stage

cat << EOF > kali-${architecture}/cleanup
#!/bin/bash
rm -rf /root/.bash_history
apt-get update
apt-get clean
rm -f /0
rm -f /hs_err*
rm -f cleanup
rm -f /usr/bin/qemu*
EOF

chmod 755 kali-${architecture}/cleanup
LANG=C systemd-nspawn -M ${machine} -D kali-${architecture} /cleanup

#umount kali-$architecture/proc/sys/fs/binfmt_misc
#umount kali-$architecture/dev/pts
#umount kali-$architecture/dev/
#umount kali-$architecture/proc

# Enable login over serial
echo "T0:23:respawn:/sbin/agetty -L ttyAMA0 115200 vt100" >> ${basedir}/kali-${architecture}/etc/inittab

cat << EOF > ${basedir}/kali-${architecture}/etc/apt/sources.list
deb http://http.kali.org/kali kali-rolling main non-free contrib
deb-src http://http.kali.org/kali kali-rolling main non-free contrib
EOF

# Uncomment this if you use apt-cacher-ng otherwise git clones will fail.
#unset http_proxy

# Kernel section. If you want to use a custom kernel, or configuration, replace
# them in this section.

cd ${TOPDIR}

# RPI Firmware
git clone --depth 1 https://github.com/raspberrypi/firmware.git rpi-firmware
cp -rf rpi-firmware/boot/* ${basedir}/kali-${architecture}/boot/
rm -rf rpi-firmware

# Setup build
cd ${TOPDIR}
git clone --depth 1 https://github.com/nethunteros/re4son-raspberrypi-linux.git -b rpi-4.9.y-nexutil ${basedir}/kali-${architecture}/usr/src/kernel
cd ${basedir}/kali-${architecture}/usr/src/kernel

# Set default defconfig
export ARCH=arm
export CROSS_COMPILE=arm-linux-gnueabihf-

# Set default defconfig
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- bcmrpi_defconfig

# Build kernel
make -j $(grep -c processor /proc/cpuinfo)

# Make kernel modules
make modules_install INSTALL_MOD_PATH=${basedir}/kali-${architecture}

# Copy kernel to boot
perl scripts/mkknlimg --dtok arch/arm/boot/zImage ${basedir}/kali-${architecture}/boot/kernel.img
cp arch/arm/boot/dts/*.dtb ${basedir}/kali-${architecture}/boot/
cp arch/arm/boot/dts/overlays/*.dtb* ${basedir}/kali-${architecture}/boot/overlays/
cp arch/arm/boot/dts/overlays/README ${basedir}/kali-${architecture}/boot/overlays/

# Make firmware and headers
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- firmware_install INSTALL_MOD_PATH=${basedir}/kali-${architecture}

# Fix up the symlink for building external modules
# kernver is used so we don't need to keep track of what the current compiled
# version is
kernver=$(ls ${basedir}/kali-${architecture}/lib/modules/)
cd ${basedir}/kali-${architecture}/lib/modules/${kernver}
rm build
rm source
ln -s /usr/src/kernel build
ln -s /usr/src/kernel source

# Copy a default config, with everything commented out so people find it when
# they go to add something when they are following instructions on a website.
cp ${basedir}/../misc/config.txt ${basedir}/kali-${architecture}/boot/config.txt

cat << EOF >> ${basedir}/kali-${architecture}/boot/config.txt
dtoverlay=dwc2
EOF

# Create cmdline.txt file
cat << EOF > ${basedir}/kali-${architecture}/boot/cmdline.txt
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
EOF

# systemd doesn't seem to be generating the fstab properly for some people, so
# let's create one.
cat << EOF > ${basedir}/kali-${architecture}/etc/fstab
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults          0       0
/dev/mmcblk0p1  /boot           vfat    defaults          0       2
/dev/mmcblk0p2  /               ext4    defaults,noatime  0       1
EOF


# rpi-wiggle
mkdir -p ${basedir}/kali-${architecture}/root/scripts
wget https://raw.github.com/offensive-security/rpiwiggle/master/rpi-wiggle -O ${basedir}/kali-${architecture}/root/scripts/rpi-wiggle.sh
chmod 755 ${basedir}/kali-${architecture}/root/scripts/rpi-wiggle.sh

# Firmware needed for rpi3 wifi (copy nexmon firmware)
mkdir -p ${basedir}/kali-${architecture}/lib/firmware/brcm/
cp ${basedir}/../misc/rpi3/brcmfmac43430-sdio-nexmon.bin ${basedir}/kali-${architecture}/lib/firmware/brcm/brcmfmac43430-sdio.bin
cp ${basedir}/../misc/rpi3/brcmfmac43430-sdio.txt ${basedir}/kali-${architecture}/lib/firmware/brcm/

# Copy nexutil
cp ${basedir}/../misc/rpi3/nexutil-pi0 ${basedir}/kali-${architecture}/usr/bin/nexutil
chmod 755 ${basedir}/kali-${architecture}/usr/bin/nexutil

cd ${basedir}

cp ${basedir}/../misc/zram ${basedir}/kali-${architecture}/etc/init.d/zram
chmod 755 ${basedir}/kali-${architecture}/etc/init.d/zram

sed -i -e 's/^#PermitRootLogin.*/PermitRootLogin yes/' ${basedir}/kali-${architecture}/etc/ssh/sshd_config

# Create the disk and partition it
echo "Creating image file ${imagename}.img"
dd if=/dev/zero of=${basedir}/${imagename}.img bs=1M count=${size}
parted ${imagename}.img --script -- mklabel msdos
parted ${imagename}.img --script -- mkpart primary fat32 0 64
parted ${imagename}.img --script -- mkpart primary ext4 64 -1

# Set the partition variables
loopdevice=`losetup -f --show ${basedir}/${imagename}.img`
device=`kpartx -va ${loopdevice}| sed -E 's/.*(loop[0-9])p.*/\1/g' | head -1`
sleep 5
device="/dev/mapper/${device}"
bootp=${device}p1
rootp=${device}p2

# Create file systems
mkfs.vfat ${bootp}
mkfs.ext4 ${rootp}

# Create the dirs for the partitions and mount them
mkdir -p ${basedir}/root
mount ${rootp} ${basedir}/root
mkdir -p ${basedir}/root/boot
mount ${bootp} ${basedir}/root/boot

echo "Rsyncing rootfs into image file"
rsync -HPavz -q ${basedir}/kali-${architecture}/ ${basedir}/root/

# Unmount partitions
sync
umount ${bootp}
umount ${rootp}
kpartx -dv ${loopdevice}
losetup -d ${loopdevice}

# Don't pixz on 32bit, there isn't enough memory to compress the images.
MACHINE_TYPE=`uname -m`
if [ ${MACHINE_TYPE} == 'x86_64' ]; then
echo "Compressing ${imagename}.img"
pixz ${basedir}/${imagename}.img ${basedir}/../${imagename}.img.xz
rm ${basedir}/${imagename}.img
fi

# Clean up all the temporary build stuff and remove the directories.
# Comment this out to keep things around if you want to see what may have gone
# wrong.
echo "Cleaning up the temporary build files..."
rm -rf ${basedir}