Decrypt Supercell storage_new.xml files

decrypt.js

const crypto = require('crypto')
const fs = require('fs')

// Constants
const PACKAGE_NAME = 'com.supercell.clashroyale'
const AES_MODE_CBC = 'cbc'
const AES_MODE_ECB = 'ecb'
const AES_IV_KEY = 'fldsjfodasjifudslfjdsaofshaufihadsf'

class AESCipher {
    constructor(key, mode = AES_MODE_CBC) {
        this.mode = mode
        this.bs = 16

        const hash = crypto.createHash('sha256')
        hash.update(key)
        this.key = hash.digest()
        this.ivKey = this.mode === AES_MODE_CBC && AES_IV_KEY.slice(0, this.bs)
    }

    decrypt(crypted) {
        const decipher = crypto.createDecipheriv(`aes-256-${this.mode}`, this.key, this.ivKey || null)
        const decrypted = decipher.update(crypted, 'base64', 'utf8')
        return decrypted + decipher.final('utf8')
    }
}

/* BUILDING THE KEY */
const keyMap = [102, 76, 120, 89, 66, 57, 77, 56, 52, 65, 98, 101, 117, 115, 69, 82, 77, 89, 57, 89, 70, 122, 86, 71]
let key = ''

for (let i = PACKAGE_NAME.length - 1; i > -1; i--) {
    const i1 = PACKAGE_NAME.codePointAt(i)
    const i2 = keyMap[i % keyMap.length]
    key += String.fromCodePoint(((i1 ^ i2) & 0x1F) + 48)
}

/* PARSE XML FILE */
const xmlContent = fs.readFileSync('./storage_new.xml', 'utf-8')
const pairs = {}
const re = /<string name="([^"]+)">([^<]+)<\/string>/g

let match
do {
    match = re.exec(xmlContent)
    if (match) pairs[match[1]] = match[2]
} while (match)

const kCipher = new AESCipher(key, AES_MODE_ECB)
const vCipher = new AESCipher(key, AES_MODE_CBC)
for (let k in pairs) console.log(`[+] ${kCipher.decrypt(k)} = ${vCipher.decrypt(pairs[k])}`)