cyberchallenge-modem/build-tgr.sh

#!/usr/bin/env bash

# for dependencies
# apt install -t build-essential libncurses-dev bison flex libssl-dev libelf-dev

#if [ $# -ne 3 ]
#  then
#    echo "No arguments supplied"
#fi

#flag1=$1
#flag2=$2

flag1="cc{prima_flag}"
flag2="cc{seconda_flag}"
password=`hexdump -n 32 -e '4/4 "%08X"' /dev/urandom`

echo "[+] Starting build script..."
mkdir -p target/overlay/var/www/html

echo "[+] Cloning buildroot"
git clone https://github.com/buildroot/buildroot.git target/buildroot

echo "[+] Adding customization files"
cp -R buildroot/* target/buildroot # copy buildroot configs
sed -i "s/###ROOTPASSWORD###/$password/g" target/buildroot/configs/tiesse_tgr_defconfig
cp -R conf/* target/overlay # copy target system config files
cp -R webpanel/* target/overlay/var/www/html # copy the webpanel
cp -R update/update.sh target/overlay #copy the update script and certificate

echo "[+] Adding firmware"
mkdir -p target/overlay/lib
cp -R firmware target/overlay/lib/ # adding binary firmware for wifi driver

echo "[+] Writing flags"
sed -i "s/##FLAG1##/$flag1/g" target/overlay/var/www/html/includes/config.php
echo $flag2 > target/overlay/flag
chmod 444 target/overlay/flag

echo "[+] Building the keygen"
mkdir -p target/overlay/usr/sbin
aarch64-linux-gnu-gcc -o target/overlay/usr/sbin/cfgbin keygen/keygen.c -static -lm
aarch64-linux-gnu-strip target/overlay/usr/sbin/cfgbin

echo "[+] Generating Update Key"
mkdir -p target/keys
openssl genrsa -out target/keys/signingkey.pem 2048
openssl rsa -in target/keys/signingkey.pem -outform PEM -pubout -out target/keys/signingpub.pem
cp target/keys/signingpub.pem target/overlay/pub.pem

echo "[+] Generating sample update package"
mkdir -p home/upgrade
echo "sample update" > home/upgrade/sample.txt
tar -cvf update.tar home
openssl dgst -sha256 -sign target/keys/signingkey.pem -out update.tar.sig update.tar
cat update.tar > update.tar.cc
cat update.tar.sig >> update.tar.cc
mv update.tar.cc target/overlay
rm -rf home update.tar update.tar.sig

echo "[+] Generating Monitoring SSH Key"
ssh-keygen -t ecdsa -f target/keys/sshkey -q -N ""
mkdir -p target/overlay/root/.ssh
cp target/keys/sshkey target/overlay/root/.ssh/authorized_keys

echo "[+] Saving the root password"
echo $password > target/keys/rootpassword

echo "[+] Building the image"
N=`grep -c '^processor' /proc/cpuinfo`
cd target/buildroot
make tiesse_tgr_defconfig
make -j$N