DeDRM_tools/Adobe_EPUB_Tools/ineptepub.pyw

341 lines
12 KiB
Python

#! /usr/bin/python
# ineptepub.pyw, version 2
# To run this program install Python 2.6 from http://www.python.org/download/
# and PyCrypto from http://www.voidspace.org.uk/python/modules.shtml#pycrypto
# (make sure to install the version for Python 2.6). Save this script file as
# ineptepub.pyw and double-click on it to run it.
# Revision history:
# 1 - Initial release
# 2 - Rename to INEPT, fix exit code
"""
Decrypt Adobe ADEPT-encrypted EPUB books.
"""
from __future__ import with_statement
__license__ = 'GPL v3'
import sys
import os
import zlib
import zipfile
from zipfile import ZipFile, ZIP_STORED, ZIP_DEFLATED
from contextlib import closing
import xml.etree.ElementTree as etree
import Tkinter
import Tkconstants
import tkFileDialog
import tkMessageBox
try:
from Crypto.Cipher import AES
from Crypto.PublicKey import RSA
except ImportError:
AES = None
RSA = None
META_NAMES = ('mimetype', 'META-INF/rights.xml', 'META-INF/encryption.xml')
NSMAP = {'adept': 'http://ns.adobe.com/adept',
'enc': 'http://www.w3.org/2001/04/xmlenc#'}
# ASN.1 parsing code from tlslite
def bytesToNumber(bytes):
total = 0L
multiplier = 1L
for count in range(len(bytes)-1, -1, -1):
byte = bytes[count]
total += multiplier * byte
multiplier *= 256
return total
class ASN1Error(Exception):
pass
class ASN1Parser(object):
class Parser(object):
def __init__(self, bytes):
self.bytes = bytes
self.index = 0
def get(self, length):
if self.index + length > len(self.bytes):
raise ASN1Error("Error decoding ASN.1")
x = 0
for count in range(length):
x <<= 8
x |= self.bytes[self.index]
self.index += 1
return x
def getFixBytes(self, lengthBytes):
bytes = self.bytes[self.index : self.index+lengthBytes]
self.index += lengthBytes
return bytes
def getVarBytes(self, lengthLength):
lengthBytes = self.get(lengthLength)
return self.getFixBytes(lengthBytes)
def getFixList(self, length, lengthList):
l = [0] * lengthList
for x in range(lengthList):
l[x] = self.get(length)
return l
def getVarList(self, length, lengthLength):
lengthList = self.get(lengthLength)
if lengthList % length != 0:
raise ASN1Error("Error decoding ASN.1")
lengthList = int(lengthList/length)
l = [0] * lengthList
for x in range(lengthList):
l[x] = self.get(length)
return l
def startLengthCheck(self, lengthLength):
self.lengthCheck = self.get(lengthLength)
self.indexCheck = self.index
def setLengthCheck(self, length):
self.lengthCheck = length
self.indexCheck = self.index
def stopLengthCheck(self):
if (self.index - self.indexCheck) != self.lengthCheck:
raise ASN1Error("Error decoding ASN.1")
def atLengthCheck(self):
if (self.index - self.indexCheck) < self.lengthCheck:
return False
elif (self.index - self.indexCheck) == self.lengthCheck:
return True
else:
raise ASN1Error("Error decoding ASN.1")
def __init__(self, bytes):
p = self.Parser(bytes)
p.get(1)
self.length = self._getASN1Length(p)
self.value = p.getFixBytes(self.length)
def getChild(self, which):
p = self.Parser(self.value)
for x in range(which+1):
markIndex = p.index
p.get(1)
length = self._getASN1Length(p)
p.getFixBytes(length)
return ASN1Parser(p.bytes[markIndex:p.index])
def _getASN1Length(self, p):
firstLength = p.get(1)
if firstLength<=127:
return firstLength
else:
lengthLength = firstLength & 0x7F
return p.get(lengthLength)
class ZipInfo(zipfile.ZipInfo):
def __init__(self, *args, **kwargs):
if 'compress_type' in kwargs:
compress_type = kwargs.pop('compress_type')
super(ZipInfo, self).__init__(*args, **kwargs)
self.compress_type = compress_type
class Decryptor(object):
def __init__(self, bookkey, encryption):
enc = lambda tag: '{%s}%s' % (NSMAP['enc'], tag)
self._aes = AES.new(bookkey, AES.MODE_CBC)
encryption = etree.fromstring(encryption)
self._encrypted = encrypted = set()
expr = './%s/%s/%s' % (enc('EncryptedData'), enc('CipherData'),
enc('CipherReference'))
for elem in encryption.findall(expr):
path = elem.get('URI', None)
if path is not None:
encrypted.add(path)
def decompress(self, bytes):
dc = zlib.decompressobj(-15)
bytes = dc.decompress(bytes)
ex = dc.decompress('Z') + dc.flush()
if ex:
bytes = bytes + ex
return bytes
def decrypt(self, path, data):
if path in self._encrypted:
data = self._aes.decrypt(data)[16:]
data = data[:-ord(data[-1])]
data = self.decompress(data)
return data
class ADEPTError(Exception):
pass
def cli_main(argv=sys.argv):
progname = os.path.basename(argv[0])
if AES is None:
print "%s: This script requires PyCrypto, which must be installed " \
"separately. Read the top-of-script comment for details." % \
(progname,)
return 1
if len(argv) != 4:
print "usage: %s KEYFILE INBOOK OUTBOOK" % (progname,)
return 1
keypath, inpath, outpath = argv[1:]
with open(keypath, 'rb') as f:
keyder = f.read()
key = ASN1Parser([ord(x) for x in keyder])
key = [bytesToNumber(key.getChild(x).value) for x in xrange(1, 4)]
rsa = RSA.construct(key)
with closing(ZipFile(open(inpath, 'rb'))) as inf:
namelist = set(inf.namelist())
if 'META-INF/rights.xml' not in namelist or \
'META-INF/encryption.xml' not in namelist:
raise ADEPTError('%s: not an ADEPT EPUB' % (inpath,))
for name in META_NAMES:
namelist.remove(name)
rights = etree.fromstring(inf.read('META-INF/rights.xml'))
adept = lambda tag: '{%s}%s' % (NSMAP['adept'], tag)
expr = './/%s' % (adept('encryptedKey'),)
bookkey = ''.join(rights.findtext(expr))
bookkey = rsa.decrypt(bookkey.decode('base64'))
# Padded as per RSAES-PKCS1-v1_5
if bookkey[-17] != '\x00':
raise ADEPTError('problem decrypting session key')
encryption = inf.read('META-INF/encryption.xml')
decryptor = Decryptor(bookkey[-16:], encryption)
kwds = dict(compression=ZIP_DEFLATED, allowZip64=False)
with closing(ZipFile(open(outpath, 'wb'), 'w', **kwds)) as outf:
zi = ZipInfo('mimetype', compress_type=ZIP_STORED)
outf.writestr(zi, inf.read('mimetype'))
for path in namelist:
data = inf.read(path)
outf.writestr(path, decryptor.decrypt(path, data))
return 0
class DecryptionDialog(Tkinter.Frame):
def __init__(self, root):
Tkinter.Frame.__init__(self, root, border=5)
self.status = Tkinter.Label(self, text='Select files for decryption')
self.status.pack(fill=Tkconstants.X, expand=1)
body = Tkinter.Frame(self)
body.pack(fill=Tkconstants.X, expand=1)
sticky = Tkconstants.E + Tkconstants.W
body.grid_columnconfigure(1, weight=2)
Tkinter.Label(body, text='Key file').grid(row=0)
self.keypath = Tkinter.Entry(body, width=30)
self.keypath.grid(row=0, column=1, sticky=sticky)
if os.path.exists('adeptkey.der'):
self.keypath.insert(0, 'adeptkey.der')
button = Tkinter.Button(body, text="...", command=self.get_keypath)
button.grid(row=0, column=2)
Tkinter.Label(body, text='Input file').grid(row=1)
self.inpath = Tkinter.Entry(body, width=30)
self.inpath.grid(row=1, column=1, sticky=sticky)
button = Tkinter.Button(body, text="...", command=self.get_inpath)
button.grid(row=1, column=2)
Tkinter.Label(body, text='Output file').grid(row=2)
self.outpath = Tkinter.Entry(body, width=30)
self.outpath.grid(row=2, column=1, sticky=sticky)
button = Tkinter.Button(body, text="...", command=self.get_outpath)
button.grid(row=2, column=2)
buttons = Tkinter.Frame(self)
buttons.pack()
botton = Tkinter.Button(
buttons, text="Decrypt", width=10, command=self.decrypt)
botton.pack(side=Tkconstants.LEFT)
Tkinter.Frame(buttons, width=10).pack(side=Tkconstants.LEFT)
button = Tkinter.Button(
buttons, text="Quit", width=10, command=self.quit)
button.pack(side=Tkconstants.RIGHT)
def get_keypath(self):
keypath = tkFileDialog.askopenfilename(
parent=None, title='Select ADEPT key file',
defaultextension='.der', filetypes=[('DER-encoded files', '.der'),
('All Files', '.*')])
if keypath:
keypath = os.path.normpath(keypath)
self.keypath.delete(0, Tkconstants.END)
self.keypath.insert(0, keypath)
return
def get_inpath(self):
inpath = tkFileDialog.askopenfilename(
parent=None, title='Select ADEPT-encrypted EPUB file to decrypt',
defaultextension='.epub', filetypes=[('EPUB files', '.epub'),
('All files', '.*')])
if inpath:
inpath = os.path.normpath(inpath)
self.inpath.delete(0, Tkconstants.END)
self.inpath.insert(0, inpath)
return
def get_outpath(self):
outpath = tkFileDialog.asksaveasfilename(
parent=None, title='Select unencrypted EPUB file to produce',
defaultextension='.epub', filetypes=[('EPUB files', '.epub'),
('All files', '.*')])
if outpath:
outpath = os.path.normpath(outpath)
self.outpath.delete(0, Tkconstants.END)
self.outpath.insert(0, outpath)
return
def decrypt(self):
keypath = self.keypath.get()
inpath = self.inpath.get()
outpath = self.outpath.get()
if not keypath or not os.path.exists(keypath):
self.status['text'] = 'Specified key file does not exist'
return
if not inpath or not os.path.exists(inpath):
self.status['text'] = 'Specified input file does not exist'
return
if not outpath:
self.status['text'] = 'Output file not specified'
return
if inpath == outpath:
self.status['text'] = 'Must have different input and output files'
return
argv = [sys.argv[0], keypath, inpath, outpath]
self.status['text'] = 'Decrypting...'
try:
cli_main(argv)
except Exception, e:
self.status['text'] = 'Error: ' + str(e)
return
self.status['text'] = 'File successfully decrypted'
def gui_main():
root = Tkinter.Tk()
if AES is None:
root.withdraw()
tkMessageBox.showerror(
"INEPT EPUB Decrypter",
"This script requires PyCrypto, which must be installed "
"separately. Read the top-of-script comment for details.")
return 1
root.title('INEPT EPUB Decrypter')
root.resizable(True, False)
root.minsize(300, 0)
DecryptionDialog(root).pack(fill=Tkconstants.X, expand=1)
root.mainloop()
return 0
if __name__ == '__main__':
# sys.exit(cli_main())
sys.exit(gui_main())