#!/bin/bash

platform="linux"

iv_k93=781b9672a86ba1b41f8b7fa0af714c94
key_k93=db03d63a767b5211d644fccd3e85ef4d5704c94d7589e0fa9ca475a353d8734b

iv_k94=883c92ed915e4d2481570a062583495b
key_k94=ccfadf3732904885d38f963cce035d7e03b387b67212d526503c85773b58e52f

iv_k95=460116385cca6d5596221c58ae122669
key_k95=7852f1fd93d9d49ebea44021081e8f1dffa336d0d3e9517374f8be451dd92eb7

iv_k93a=976aa656929ac699fff36715de96876d
key_k93a=5fe5c47b5620c2b40b1ca2bd1764a92d568901a24e1caf8faf0cf0f84ae11b4e

iv_p101=b21abc8689b0dea8f6e613f9f970e241
key_p101=b9ed63e4a31f5d9d4d7dddc527e65fd31d1ea48c70204e6b44551c1e6dfc52b5

iv_p102=56231fd62c6296ed0c8c411bcef602e0
key_p102=cdb2142489e5e936fa8f3540bd036f62ed0f27ddb6fec96b9fbfec5a65bc5f17

iv_p103=fa39c596b6569e572d90f0820e4e4357
key_p103=34b359fcc729a0f0d2853e786a78b245ed36a9212c8296aaab95dc0401cf07de

iv_j1=c3ea87ed43788dfc3e268abdf1af27dd
key_j1=cd3dd7eee07b9ce8b180d1526632cf86dc7fef7d52352d06af354598ab9cf2ef

iv_j2=32fcd912cb9a472ef2a6db72596ae01c
key_j2=076720d5a07e8011bdda6f6eafaf4845b40a441615cd1d7c1a9cca438ce7db17

iv_j2a=e6b041970cd611c8a1561a4c210bc476
key_j2a=aec6a888d45bd26106ac620d7d4ec0c160ab80276deedc1b50ce8f5d99dcc9af

iv_p105=a5892a58c90b6d3fb0e0b20db95070d7
key_p105=75612774968009e3f85545ac0088d0d0bb9cb4e2c2970e8f88489be0b9dfe103

iv_p106=fba6d9aaec7237891c80390e6ffa88bf
key_p106=92909dca9bfdb9193131f9ad9b628b1a4971b1cbab52c0ddd114a6253fad96c0

iv_p107=1d99e780d96c32a25ca7e4b1c7fe14c0
key_p107=4e2c14927693d61e1da375e340061521c9376007163f6ab55afbe1a03b901fd3

iv_n78=e0175b03bc29817adc312638884e0898
key_n78=0a0e0aedc8171669c9af6a229930a395959df55dcd8a3ee1fe0f4c009007df3c

iv_n94=147cdef921ed14a5c10631c5e6e02d1e
key_n94=6ea1eb62a9f403ee212c1f6b3039df093963b46739c6093407190fe3d750c69c

iv_n41=bd0c8b039a819604a30f0d39adf88572
key_n41=baf05fe0282f78c18c2e3842be4f9021919d586b55594281f5b5abd0f6e61495

iv_n42=fdad2b7a35384fa2ffc7221213ca1082
key_n42=74cd68729b800a20b1f8e8a3cb5517024a09f074eaa05b099db530fb5783275e

rm -rf iP*/ tmp/ $(ls *.shsh2)

HardwareModel=$(ideviceinfo | grep 'HardwareModel' | cut -c 16-)
HardwareModelLower=$(echo $HardwareModel | tr '[:upper:]' '[:lower:]' | sed 's/.\{2\}$//')
ProductType=$(ideviceinfo | grep 'ProductType' | cut -c 14-)
ProductVersion=$(ideviceinfo | grep 'ProductVersion' | cut -c 17-)
VersionDetect=$(echo $ProductVersion | cut -c 1)
UniqueChipID=$(ideviceinfo | grep 'UniqueChipID' | cut -c 15-)
iBSS="iBSS.$HardwareModelLower.RELEASE"
IPSW="${ProductType}_8.4.1_12H321_Restore"

clear
echo "******* 841-OTA-Downgrader *******"
echo "          - by LukeZGD            "
echo

if [ ! $HardwareModel ]
then
    echo "Please plug the device in before proceeding"
    exit
elif [ $HardwareModel == iPad2,1 ] || [ $HardwareModel == iPad2,4 ] || [ $HardwareModel == iPad2,5 ] || [ $HardwareModel == iPad3,1 ] || [ $HardwareModel == iPad3,4 ] || [ $HardwareModel == iPod5,1 ]
then
    NoBaseband=1
fi

echo "HardwareModel: $HardwareModel"
echo "ProductType: $ProductType"
echo "ProductVersion: $ProductVersion"
echo "UniqueChipID (ECID): $UniqueChipID"
echo "iBSS: $iBSS"
echo


if [ ! -e ${IPSW}.ipsw ]
then
    echo "iOS 8.4.1 IPSW is missing! Please put the IPSW on the same directory of this script"
    exit
fi

mkdir tmp

if [ ! -e tools/tsschecker_$platform ]
then
    echo "Downloading tsschecker..."
    curl -L -# "https://github.com/tihmstar/tsschecker/releases/download/v212/tsschecker_v212_mac_win_linux.zip" -o "tmp/tsschecker.zip"
    echo "Extracting tsschecker..."
    unzip -j tmp/tsschecker.zip tsschecker_$platform -d "tools/"
    chmod +x tools/tsschecker_$platform
    echo
fi
if [ ! -e tools/tsschecker_$platform ]
then
    echo "Download/extract tsschecker failed. Please run the script again"
    exit
fi

if [ ! -e tools/futurerestore_$platform ]
then
    echo "Downloading futurerestore..."
    curl -L -# "http://api.tihmstar.net/builds/futurerestore/futurerestore-latest.zip" -o "tmp/futurerestore.zip"
    echo "Extracting futurerestore..."
    unzip -j tmp/futurerestore.zip futurerestore_$platform -d "tools/"
    chmod +x tools/futurerestore_$platform
    echo 
fi
if [ ! -e tools/futurerestore_$platform ]
then
    echo "Download/extract futurerestore failed. Please run the script again"
    exit
fi

if [ ! -e /tmp/ota.json ] && [ ! -e $TMPDIR/ota.json ]
then
    echo "Downloading ota.json..."
    curl -L -# "https://api.ipsw.me/v2.1/ota.json/condensed" -o "tmp/ota.json"
    echo 'Copying ota.json to /tmp or $TMPDIR...'
    if [ $platform == macos ] 
    then
        cp tmp/ota.json $TMPDIR
    else
        cp tmp/ota.json /tmp
    fi
    echo
fi
if [ ! -e /tmp/ota.json ] && [ ! -e $TMPDIR/ota.json ]
then
    echo "Download ota.json failed. Please run the script again"
    rm -rf tmp/ 
    exit
fi

echo "Downloading OTA Firmware..."
curl -L -# "https://api.ipsw.me/v4/ota/download/$ProductType/12H321?prerequisite=12H143" -o "tmp/otafirmware.zip"
echo "Extracting BuildManifest.plist..."
unzip -j tmp/otafirmware.zip AssetData/boot/BuildManifest.plist -d "tmp/"
echo
if [ ! -e tmp/BuildManifest.plist ]
then
    echo "Download/extract BuildManifest.plist failed. Please run the script again"
    rm -rf tmp/
    exit
fi

echo "Saving 8.4.1 blobs with tsschecker..."
if [[ ! $NoBaseband ]]
then
    env "LD_PRELOAD=libcurl.so.3" tools/tsschecker_$platform -d $ProductType -i 8.4.1 -o -s -e $UniqueChipID -m tmp/BuildManifest.plist
else
    echo "Detected device has no baseband"
    env "LD_PRELOAD=libcurl.so.3" tools/tsschecker_$platform -d $ProductType -i 8.4.1 -o -s -b -e $UniqueChipID -m tmp/BuildManifest.plist
fi
echo
if [ ! -e $(ls *.shsh2) ]
then
    echo "Saving 8.4.1 blobs failed. Please run the script again"
    rm -rf tmp/ BuildManifest.plist
    exit
fi

echo "Extracting 8.4.1 IPSW..."
unzip -q ${IPSW}.ipsw -d "$IPSW/"
echo

echo "Decrypting iBSS..."
iv=iv_$HardwareModelLower
key=key_$HardwareModelLower
echo "IV = ${!iv}"
echo "Key = ${!key}"
tools/xpwntool_$platform $IPSW/Firmware/dfu/$iBSS.dfu tmp/iBSS.dec -k ${!key} -iv ${!iv} -decrypt
dd bs=64 skip=1 if=tmp/iBSS.dec of=tmp/iBSS.dec2
echo

echo "Patching iBSS..."
bspatch tmp/iBSS.dec2 tmp/pwnediBSS patches/$iBSS.patch
echo

if [[ $VersionDetect == 1 ]]
then
    kloader="kloader_hgsp"
elif [[ $VersionDetect == 5 ]]
then
    kloader="kloader5"
else
    kloader="kloader"
fi

if [[ $VersionDetect == 1 ]]
then
    WifiAddr=$(ideviceinfo | grep 'WiFiAddress' | cut -c 14-)
    WifiAddrDecr=$(echo $(printf "%x\n" $(expr $(printf "%d\n" 0x$(echo "${WifiAddr}" | tr -d ':')) - 1)) | sed 's/\(..\)/\1:/g;s/:$//')
    mkdir mountdir
    echo "Mounting device using ifuse..."
    ifuse mountdir
    echo "Copying stuff to device..."
    cp "tools/$kloader" "tmp/pwnediBSS" "mountdir/"
    umount mountdir
    rm -rf mountdir
    echo
    echo "Enter MTerminal and run these commands:"
    echo
    echo "su"
    echo "(enter root password, default is 'alpine')"
    echo "nvram wifiaddr=$WifiAddrDecr"
    echo "cd /var/mobile/Media"
    echo "chmod 0755 kloader_hgsp"
    echo "./kloader_hgsp pwnediBSS"
    echo
else
    echo "Make sure SSH is installed and working on the device!"
    echo "Please enter Wi-Fi IP address of device for SSH connection:"
    read IPAddress
    echo "Will now connect to device using SSH"
    echo "Please enter root password when prompted (default is 'alpine')"
    echo
    echo "Copying stuff to device..."
    scp tools/$kloader tmp/pwnediBSS root@$IPAddress:/
    echo
    echo "Entering pwnDFU mode... (press Ctrl+C after entering root password to continue)"
    ssh root@$IPAddress "chmod 0755 /$kloader && /$kloader /pwnediBSS"
    echo
fi

echo "Press home/power button once when screen goes black on the device, then press [enter]"
read
echo "Will now proceed to futurerestore in 5 seconds..."
sleep 5
echo

while [ ! $ScriptDone ]
do
    
    if [[ ! $NoBaseband ]]
    then
        sudo env "LD_PRELOAD=libcurl.so.3" tools/futurerestore_$platform -t $(ls *.shsh2) --latest-baseband --use-pwndfu ${IPSW}.ipsw
    else
        echo "Detected device has no baseband"
        sudo env "LD_PRELOAD=libcurl.so.3" tools/futurerestore_$platform -t $(ls *.shsh2) --latest-baseband --use-pwndfu --no-baseband ${IPSW}.ipsw
    fi
    
    echo "futurerestore done!"
    echo "If futurerestore failed to download baseband or for some reason, you can choose to retry"
    echo "Retry? (y/n)"
    read retry
    if [ retry != y ] && [ retry != Y ]
    then
        ScriptDone=1
    fi

done

rm -rf iP*/ tmp/ $(ls *.shsh2)

echo "Script done!"