DeDRM_tools/Barnes_and_Noble_EPUB_Tools/ignobleepub.pyw
2015-02-28 10:54:59 +00:00

235 lines
8.6 KiB
Python

#! /usr/bin/python
# ignobleepub.pyw, version 1-rc2
# 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
# ignobleepub.pyw and double-click on it to run it.
# Revision history:
# 1 - Initial release
"""
Decrypt Barnes & Noble 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
except ImportError:
AES = 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#'}
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:
keyb64 = f.read()
key = keyb64.decode('base64')[:16]
aes = AES.new(key, AES.MODE_CBC)
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 B&N 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 = aes.decrypt(bookkey.decode('base64'))
bookkey = bookkey[:-ord(bookkey[-1])]
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('bnepubkey.b64'):
self.keypath.insert(0, 'bnepubkey.b64')
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 B&N EPUB key file',
defaultextension='.b64',
filetypes=[('base64-encoded files', '.b64'),
('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 B&N-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(
"Ignoble EPUB Decrypter",
"This script requires PyCrypto, which must be installed "
"separately. Read the top-of-script comment for details.")
return 1
root.title('Ignoble 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__':
if len(sys.argv) > 1:
sys.exit(cli_main())
sys.exit(gui_main())