Realta Nua Mobile - Unpack

# -*- coding: utf-8 -*-
#
# Fate Mobile DAT File Extractor v1.2
# 2015/06/11
#
# Copyright (c) 2015 w酱
# Copyright (c) 2015 Hintay <hintay(at)me.com>
# Copyright (c) 2015 dorobo-hamster

import os, codecs, sys, hashlib

#This has only been tested on fate_000.dat.
#Other files may be different so check the output for other files.
ENCRYPTION_KEY = [0x5d, 0x55, 0x82, 0xf2, 0xbe, 0x45, 0x31, 0xeb,
                  0x29, 0xbc, 0xf7, 0x2c, 0xe2, 0xb5, 0xc0, 0x5b]

def getFileInfo(input):
    postfix = {1:'', 2:'_rin', 3:'_sakura', 4:''}
    if(input == 5):
        while True:
            custom_fileinfo = raw_input('Please input fileinfo txt\'s filename without extension: ')
            fileinfo_path = os.path.join('sys', '%s.txt' % custom_fileinfo)
            if(os.path.exists(fileinfo_path)):
                break
            else:
                print(u'%s not exits, please input again.' % fileinfo_path)
    else:
        fileinfo_path = os.path.join('sys', 'fileinfo%s.txt' % postfix[input])
    fp = codecs.open(fileinfo_path, 'rb', 'utf-8')
    lines = fp.readlines()
    lst = []
    for line in lines:
        if '::' in line:
            name, extension, container_name, offset, size, file_hash, encrypted = line.split('::')[:7]
            offset = int(offset , 10)
            size = int(size, 10)
            lst.append((name, extension, offset, size, file_hash, encrypted))
    return lst

def view_bar(num=1, sum=100, bar_word=":"):
    rate = float(num) / float(sum)
    rate_num = int(rate * 100)
    print('\r%d%%' % (rate_num))
#    for i in range(0, rate_num):
#        os.write(1, bar_word)
#    sys.stdout.flush()

def decrypt(file_info, data):
    print('Decrypt '+file_info['name']+'.'+file_info['extension'])
    i = 0
    offset = file_info['start']
    data = bytearray(data)
    while i < file_info['length']:
        data[i] = data[i]^(offset%256)^ENCRYPTION_KEY[offset%16]
        i+=1
        offset+=1
    return data

def main(input):
    if(input == 5):
        while True:
            filename = raw_input('Please input dat filename without extension: ')
            if(os.path.exists('%s.dat'%filename)):
                break
            else:
                print(u'%s.dat not exits, please input again.'%filename)
    else:
        filename = ''
    datname = {1:'saber', 2:'rin', 3:'sakura', 4:'fate_000', 5:filename}

    lst = getFileInfo(input)
    with open('%s.dat' % datname[input], 'rb') as fp:
        if not os.path.exists('%s.dat_unpacked' % datname[input]):
            os.makedirs('%s.dat_unpacked' % datname[input])
        lstsum = len(lst)
        for i in range(lstsum):
            view_bar(i, lstsum)
            (name, extension, offset, size, file_hash, encrypted) = lst[i]
            fp.seek(offset)
            dat = fp.read(size)
            file_path = os.path.join(u'%s.dat_unpacked' % datname[input], '%s.%s' % (name , extension))
            dest = open(file_path, 'wb')
            if(encrypted == '1'):
                file_info = {'name':name, 'extension':extension, 'start':offset, 'length':size}
                dat = decrypt(file_info, dat)
            dest.write(dat)
            dest.close()

            # Verify output file's hash
            try:
                hash_function = hashlib.md5()
                with open(file_path, mode='rb') as input_file:
                    buf = input_file.read()
                    hash_function.update(buf)
                    new_hash = hash_function.hexdigest()
                if(new_hash != file_hash):
                    raise
            except:
                print(u'Hash validation failed, maybe the dat file is broken or the encryption key has been changed.')
        fp.close()

if __name__ == '__main__':
    print(u'1. saber.dat')
    print(u'2. rin.dat')
    print(u'3. sakura.dat')
    print(u'4. fate_000.dat')
    print(u'5. other .dat file')
    while True:
        input = int(input('Please select dat file what you want unpack: '))
        if input == 1 or input == 2 or input == 3 or input == 4 or input == 5:
            break
        else:
            print(u'Your input is incorrect, please input again.')
    main(input)