Unpacks PAK files from the game Abyss Boat by Leaf

abyss_boat_pak_dump.py

# dumps PAK files from the game Abyss Boat by Leaf

import os
import struct

def printable(d):
    s = ""
    for c in d: s += chr(c) if (c >= 0x20 and c <= 126) else '.'
    return s

def printhex(d,space=" "):
    s = ""
    for c in d: s += ("%02X" % c) + space
    return s

def printinspect(d):
    return printhex(d) + " [" + printable(d) + "]"

def pak_contents(filename,unpack=True):
    print("PAK contents: " + filename)
    pak = open(filename,"rb").read()
    # first 4 bytes are fourCC 'L','A','C',0
    print("FourCC: " + printinspect(pak[0:4]))
    # next is a file count
    filecount = struct.unpack("<L",pak[4:8])[0]
    print("File   Offset     Size --- %d files" % filecount)
    # next is a file directory, 36 bytes each
    for i in range(filecount):
        o = 8 + (36 * i)
        en = pak[o:o+28] # filename (28 bytes)
        (es,eo) = struct.unpack("<LL",pak[o+28:o+36]) # file size, file offset (4 bytes each)
        while en[-1] == 0x01: en = en[0:-1] # strip terminal 01
        while en[-1] == 0x00: en = en[0:-1] # strip trailing zeroes
        # the encoding seems to be ASCII with an XOR inversion, guessed it by assuming D1 = '.' from what looked like file extensions
        en = bytes((x ^ 0xFF) for x in en)
        en = printable(en)
        print("%03d: %8X %8X [%s]" % (i,eo,es,en))
        if unpack:
            unpack_dir = filename[:-4] + '_' + filename[-3:]
            if not os.path.exists(unpack_dir):
                os.makedirs(unpack_dir)
            open(os.path.join(unpack_dir,en),"wb").write(pak[eo:eo+es])
    print("End of PAK.")

for (root,dirs,files) in os.walk("."):
    for f in files:
        if f.lower().endswith(".pak"):
            pak_contents(os.path.join(root,f))