475 lines
20 KiB
Python
Executable File
475 lines
20 KiB
Python
Executable File
#!/usr/bin/env python3
|
||
# -*- coding: utf-8 -*-
|
||
|
||
# mobidedrm.py
|
||
# Copyright © 2008 The Dark Reverser
|
||
# Portions © 2008–2020 Apprentice Harper et al.
|
||
|
||
from __future__ import print_function
|
||
__license__ = 'GPL v3'
|
||
__version__ = "1.1"
|
||
|
||
# This is a python script. You need a Python interpreter to run it.
|
||
# For example, ActiveState Python, which exists for windows.
|
||
#
|
||
# Changelog
|
||
# 0.01 - Initial version
|
||
# 0.02 - Huffdic compressed books were not properly decrypted
|
||
# 0.03 - Wasn't checking MOBI header length
|
||
# 0.04 - Wasn't sanity checking size of data record
|
||
# 0.05 - It seems that the extra data flags take two bytes not four
|
||
# 0.06 - And that low bit does mean something after all :-)
|
||
# 0.07 - The extra data flags aren't present in MOBI header < 0xE8 in size
|
||
# 0.08 - ...and also not in Mobi header version < 6
|
||
# 0.09 - ...but they are there with Mobi header version 6, header size 0xE4!
|
||
# 0.10 - Outputs unencrypted files as-is, so that when run as a Calibre
|
||
# import filter it works when importing unencrypted files.
|
||
# Also now handles encrypted files that don't need a specific PID.
|
||
# 0.11 - use autoflushed stdout and proper return values
|
||
# 0.12 - Fix for problems with metadata import as Calibre plugin, report errors
|
||
# 0.13 - Formatting fixes: retabbed file, removed trailing whitespace
|
||
# and extra blank lines, converted CR/LF pairs at ends of each line,
|
||
# and other cosmetic fixes.
|
||
# 0.14 - Working out when the extra data flags are present has been problematic
|
||
# Versions 7 through 9 have tried to tweak the conditions, but have been
|
||
# only partially successful. Closer examination of lots of sample
|
||
# files reveals that a confusion has arisen because trailing data entries
|
||
# are not encrypted, but it turns out that the multibyte entries
|
||
# in utf8 file are encrypted. (Although neither kind gets compressed.)
|
||
# This knowledge leads to a simplification of the test for the
|
||
# trailing data byte flags - version 5 and higher AND header size >= 0xE4.
|
||
# 0.15 - Now outputs 'heartbeat', and is also quicker for long files.
|
||
# 0.16 - And reverts to 'done' not 'done.' at the end for unswindle compatibility.
|
||
# 0.17 - added modifications to support its use as an imported python module
|
||
# both inside calibre and also in other places (ie K4DeDRM tools)
|
||
# 0.17a- disabled the standalone plugin feature since a plugin can not import
|
||
# a plugin
|
||
# 0.18 - It seems that multibyte entries aren't encrypted in a v7 file...
|
||
# Removed the disabled Calibre plug-in code
|
||
# Permit use of 8-digit PIDs
|
||
# 0.19 - It seems that multibyte entries aren't encrypted in a v6 file either.
|
||
# 0.20 - Correction: It seems that multibyte entries are encrypted in a v6 file.
|
||
# 0.21 - Added support for multiple pids
|
||
# 0.22 - revised structure to hold MobiBook as a class to allow an extended interface
|
||
# 0.23 - fixed problem with older files with no EXTH section
|
||
# 0.24 - add support for type 1 encryption and 'TEXtREAd' books as well
|
||
# 0.25 - Fixed support for 'BOOKMOBI' type 1 encryption
|
||
# 0.26 - Now enables Text-To-Speech flag and sets clipping limit to 100%
|
||
# 0.27 - Correct pid metadata token generation to match that used by skindle (Thank You Bart!)
|
||
# 0.28 - slight additional changes to metadata token generation (None -> '')
|
||
# 0.29 - It seems that the ideas about when multibyte trailing characters were
|
||
# included in the encryption were wrong. They are for DOC compressed
|
||
# files, but they are not for HUFF/CDIC compress files!
|
||
# 0.30 - Modified interface slightly to work better with new calibre plugin style
|
||
# 0.31 - The multibyte encrytion info is true for version 7 files too.
|
||
# 0.32 - Added support for "Print Replica" Kindle ebooks
|
||
# 0.33 - Performance improvements for large files (concatenation)
|
||
# 0.34 - Performance improvements in decryption (libalfcrypto)
|
||
# 0.35 - add interface to get mobi_version
|
||
# 0.36 - fixed problem with TEXtREAd and getBookTitle interface
|
||
# 0.37 - Fixed double announcement for stand-alone operation
|
||
# 0.38 - Unicode used wherever possible, cope with absent alfcrypto
|
||
# 0.39 - Fixed problem with TEXtREAd and getBookType interface
|
||
# 0.40 - moved unicode_argv call inside main for Windows DeDRM compatibility
|
||
# 0.41 - Fixed potential unicode problem in command line calls
|
||
# 0.42 - Added GPL v3 licence. updated/removed some print statements
|
||
# 1.0 - Python 3 compatibility for calibre 5.0
|
||
# 1.1 - Speed Python PC1 implementation up a little bit
|
||
|
||
import sys
|
||
import os
|
||
import struct
|
||
import binascii
|
||
from alfcrypto import Pukall_Cipher
|
||
|
||
from utilities import SafeUnbuffered
|
||
|
||
from argv_utils import unicode_argv
|
||
|
||
|
||
class DrmException(Exception):
|
||
pass
|
||
|
||
|
||
#
|
||
# MobiBook Utility Routines
|
||
#
|
||
|
||
# Implementation of Pukall Cipher 1
|
||
def PC1(key, src, decryption=True):
|
||
# if we can get it from alfcrypto, use that
|
||
try:
|
||
return Pukall_Cipher().PC1(key,src,decryption)
|
||
except:
|
||
raise
|
||
|
||
# accepts unicode returns unicode
|
||
def checksumPid(s):
|
||
letters = 'ABCDEFGHIJKLMNPQRSTUVWXYZ123456789'
|
||
crc = (~binascii.crc32(s.encode('utf-8'),-1))&0xFFFFFFFF
|
||
crc = crc ^ (crc >> 16)
|
||
res = s
|
||
l = len(letters)
|
||
for i in (0,1):
|
||
b = crc & 0xff
|
||
pos = (b // l) ^ (b % l)
|
||
res += letters[pos%l]
|
||
crc >>= 8
|
||
return res
|
||
|
||
# expects bytearray
|
||
def getSizeOfTrailingDataEntries(ptr, size, flags):
|
||
def getSizeOfTrailingDataEntry(ptr, size):
|
||
bitpos, result = 0, 0
|
||
if size <= 0:
|
||
return result
|
||
while True:
|
||
v = ptr[size-1]
|
||
result |= (v & 0x7F) << bitpos
|
||
bitpos += 7
|
||
size -= 1
|
||
if (v & 0x80) != 0 or (bitpos >= 28) or (size == 0):
|
||
return result
|
||
num = 0
|
||
testflags = flags >> 1
|
||
while testflags:
|
||
if testflags & 1:
|
||
num += getSizeOfTrailingDataEntry(ptr, size - num)
|
||
testflags >>= 1
|
||
# Check the low bit to see if there's multibyte data present.
|
||
# if multibyte data is included in the encryped data, we'll
|
||
# have already cleared this flag.
|
||
if flags & 1:
|
||
num += (ptr[size - num - 1] & 0x3) + 1
|
||
return num
|
||
|
||
|
||
|
||
class MobiBook:
|
||
def loadSection(self, section):
|
||
if (section + 1 == self.num_sections):
|
||
endoff = len(self.data_file)
|
||
else:
|
||
endoff = self.sections[section + 1][0]
|
||
off = self.sections[section][0]
|
||
return self.data_file[off:endoff]
|
||
|
||
def cleanup(self):
|
||
# to match function in Topaz book
|
||
pass
|
||
|
||
def __init__(self, infile):
|
||
print("MobiDeDrm v{0:s}.\nCopyright © 2008-2022 The Dark Reverser, Apprentice Harper et al.".format(__version__))
|
||
|
||
# initial sanity check on file
|
||
self.data_file = open(infile, 'rb').read()
|
||
self.mobi_data = ''
|
||
self.header = self.data_file[0:78]
|
||
if self.header[0x3C:0x3C+8] != b'BOOKMOBI' and self.header[0x3C:0x3C+8] != b'TEXtREAd':
|
||
raise DrmException("Invalid file format")
|
||
self.magic = self.header[0x3C:0x3C+8]
|
||
self.crypto_type = -1
|
||
|
||
# build up section offset and flag info
|
||
self.num_sections, = struct.unpack('>H', self.header[76:78])
|
||
self.sections = []
|
||
for i in range(self.num_sections):
|
||
offset, a1,a2,a3,a4 = struct.unpack('>LBBBB', self.data_file[78+i*8:78+i*8+8])
|
||
flags, val = a1, a2<<16|a3<<8|a4
|
||
self.sections.append( (offset, flags, val) )
|
||
|
||
# parse information from section 0
|
||
self.sect = self.loadSection(0)
|
||
self.records, = struct.unpack('>H', self.sect[0x8:0x8+2])
|
||
self.compression, = struct.unpack('>H', self.sect[0x0:0x0+2])
|
||
|
||
# det default values before PalmDoc test
|
||
self.print_replica = False
|
||
self.extra_data_flags = 0
|
||
self.meta_array = {}
|
||
self.mobi_length = 0
|
||
self.mobi_codepage = 1252
|
||
self.mobi_version = -1
|
||
|
||
if self.magic == b'TEXtREAd':
|
||
print("PalmDoc format book detected.")
|
||
return
|
||
|
||
self.mobi_length, = struct.unpack('>L',self.sect[0x14:0x18])
|
||
self.mobi_codepage, = struct.unpack('>L',self.sect[0x1c:0x20])
|
||
self.mobi_version, = struct.unpack('>L',self.sect[0x68:0x6C])
|
||
#print "MOBI header version {0:d}, header length {1:d}".format(self.mobi_version, self.mobi_length)
|
||
if (self.mobi_length >= 0xE4) and (self.mobi_version >= 5):
|
||
self.extra_data_flags, = struct.unpack('>H', self.sect[0xF2:0xF4])
|
||
#print "Extra Data Flags: {0:d}".format(self.extra_data_flags)
|
||
if (self.compression != 17480):
|
||
# multibyte utf8 data is included in the encryption for PalmDoc compression
|
||
# so clear that byte so that we leave it to be decrypted.
|
||
self.extra_data_flags &= 0xFFFE
|
||
|
||
# if exth region exists parse it for metadata array
|
||
try:
|
||
exth_flag, = struct.unpack('>L', self.sect[0x80:0x84])
|
||
exth = b''
|
||
if exth_flag & 0x40:
|
||
exth = self.sect[16 + self.mobi_length:]
|
||
if (len(exth) >= 12) and (exth[:4] == b'EXTH'):
|
||
nitems, = struct.unpack('>I', exth[8:12])
|
||
pos = 12
|
||
for i in range(nitems):
|
||
type, size = struct.unpack('>II', exth[pos: pos + 8])
|
||
content = exth[pos + 8: pos + size]
|
||
self.meta_array[type] = content
|
||
# reset the text to speech flag and clipping limit, if present
|
||
if type == 401 and size == 9:
|
||
# set clipping limit to 100%
|
||
self.patchSection(0, b'\144', 16 + self.mobi_length + pos + 8)
|
||
elif type == 404 and size == 9:
|
||
# make sure text to speech is enabled
|
||
self.patchSection(0, b'\0', 16 + self.mobi_length + pos + 8)
|
||
elif type == 405 and size == 9:
|
||
# remove rented book flag
|
||
self.patchSection(0, b'\0', 16 + self.mobi_length + pos + 8)
|
||
elif type == 406 and size == 16:
|
||
# remove rental due date
|
||
self.patchSection(0, b'\0'*8, 16 + self.mobi_length + pos + 8)
|
||
elif type == 208:
|
||
# remove watermark (atv:kin: stuff)
|
||
self.patchSection(0, b'\0'*(size-8), 16 + self.mobi_length + pos + 8)
|
||
# print type, size, content, content.encode('hex')
|
||
pos += size
|
||
except Exception as e:
|
||
print("Cannot set meta_array: Error: {:s}".format(e.args[0]))
|
||
|
||
#returns unicode
|
||
def getBookTitle(self):
|
||
codec_map = {
|
||
1252 : 'windows-1252',
|
||
65001 : 'utf-8',
|
||
}
|
||
title = b''
|
||
codec = 'windows-1252'
|
||
if self.magic == b'BOOKMOBI':
|
||
if 503 in self.meta_array:
|
||
title = self.meta_array[503]
|
||
else:
|
||
toff, tlen = struct.unpack('>II', self.sect[0x54:0x5c])
|
||
tend = toff + tlen
|
||
title = self.sect[toff:tend]
|
||
if self.mobi_codepage in codec_map.keys():
|
||
codec = codec_map[self.mobi_codepage]
|
||
if title == b'':
|
||
title = self.header[:32]
|
||
title = title.split(b'\0')[0]
|
||
return title.decode(codec)
|
||
|
||
def getPIDMetaInfo(self):
|
||
rec209 = b''
|
||
token = b''
|
||
if 209 in self.meta_array:
|
||
rec209 = self.meta_array[209]
|
||
data = rec209
|
||
# The 209 data comes in five byte groups. Interpret the last four bytes
|
||
# of each group as a big endian unsigned integer to get a key value
|
||
# if that key exists in the meta_array, append its contents to the token
|
||
for i in range(0,len(data),5):
|
||
val, = struct.unpack('>I',data[i+1:i+5])
|
||
sval = self.meta_array.get(val,b'')
|
||
token += sval
|
||
return rec209, token
|
||
|
||
# new must be byte array
|
||
def patch(self, off, new):
|
||
self.data_file = self.data_file[:off] + new + self.data_file[off+len(new):]
|
||
|
||
# new must be byte array
|
||
def patchSection(self, section, new, in_off = 0):
|
||
if (section + 1 == self.num_sections):
|
||
endoff = len(self.data_file)
|
||
else:
|
||
endoff = self.sections[section + 1][0]
|
||
off = self.sections[section][0]
|
||
assert off + in_off + len(new) <= endoff
|
||
self.patch(off + in_off, new)
|
||
|
||
# pids in pidlist must be unicode, returned key is byte array, pid is unicode
|
||
def parseDRM(self, data, count, pidlist):
|
||
found_key = None
|
||
keyvec1 = b'\x72\x38\x33\xB0\xB4\xF2\xE3\xCA\xDF\x09\x01\xD6\xE2\xE0\x3F\x96'
|
||
for pid in pidlist:
|
||
bigpid = pid.encode('utf-8').ljust(16,b'\0')
|
||
temp_key = PC1(keyvec1, bigpid, False)
|
||
temp_key_sum = sum(temp_key) & 0xff
|
||
found_key = None
|
||
for i in range(count):
|
||
verification, size, type, cksum, cookie = struct.unpack('>LLLBxxx32s', data[i*0x30:i*0x30+0x30])
|
||
if cksum == temp_key_sum:
|
||
cookie = PC1(temp_key, cookie)
|
||
ver,flags,finalkey,expiry,expiry2 = struct.unpack('>LL16sLL', cookie)
|
||
if verification == ver and (flags & 0x1F) == 1:
|
||
found_key = finalkey
|
||
break
|
||
if found_key != None:
|
||
break
|
||
if not found_key:
|
||
# Then try the default encoding that doesn't require a PID
|
||
pid = '00000000'
|
||
temp_key = keyvec1
|
||
temp_key_sum = sum(temp_key) & 0xff
|
||
for i in range(count):
|
||
verification, size, type, cksum, cookie = struct.unpack('>LLLBxxx32s', data[i*0x30:i*0x30+0x30])
|
||
if cksum == temp_key_sum:
|
||
cookie = PC1(temp_key, cookie)
|
||
ver,flags,finalkey,expiry,expiry2 = struct.unpack('>LL16sLL', cookie)
|
||
if verification == ver:
|
||
found_key = finalkey
|
||
break
|
||
return [found_key,pid]
|
||
|
||
def getFile(self, outpath):
|
||
open(outpath,'wb').write(self.mobi_data)
|
||
|
||
def getBookType(self):
|
||
if self.print_replica:
|
||
return "Print Replica"
|
||
if self.mobi_version >= 8:
|
||
return "Kindle Format 8"
|
||
if self.mobi_version >= 0:
|
||
return "Mobipocket {0:d}".format(self.mobi_version)
|
||
return "PalmDoc"
|
||
|
||
def getBookExtension(self):
|
||
if self.print_replica:
|
||
return ".azw4"
|
||
if self.mobi_version >= 8:
|
||
return ".azw3"
|
||
return ".mobi"
|
||
|
||
# pids in pidlist may be unicode or bytearrays or bytes
|
||
def processBook(self, pidlist):
|
||
crypto_type, = struct.unpack('>H', self.sect[0xC:0xC+2])
|
||
print("Crypto Type is: {0:d}".format(crypto_type))
|
||
self.crypto_type = crypto_type
|
||
if crypto_type == 0:
|
||
print("This book is not encrypted.")
|
||
# we must still check for Print Replica
|
||
self.print_replica = (self.loadSection(1)[0:4] == b'%MOP')
|
||
self.mobi_data = self.data_file
|
||
return
|
||
if crypto_type != 2 and crypto_type != 1:
|
||
raise DrmException("Cannot decode unknown Mobipocket encryption type {0:d}".format(crypto_type))
|
||
if 406 in self.meta_array:
|
||
data406 = self.meta_array[406]
|
||
val406, = struct.unpack('>Q',data406)
|
||
if val406 != 0:
|
||
print("Warning: This is a library or rented ebook ({0}). Continuing ...".format(val406))
|
||
#raise DrmException("Cannot decode library or rented ebooks.")
|
||
|
||
goodpids = []
|
||
# print("DEBUG ==== pidlist = ", pidlist)
|
||
for pid in pidlist:
|
||
if isinstance(pid,(bytearray,bytes)):
|
||
pid = pid.decode('utf-8')
|
||
if len(pid)==10:
|
||
if checksumPid(pid[0:-2]) != pid:
|
||
print("Warning: PID {0} has incorrect checksum, should have been {1}".format(pid,checksumPid(pid[0:-2])))
|
||
goodpids.append(pid[0:-2])
|
||
elif len(pid)==8:
|
||
goodpids.append(pid)
|
||
else:
|
||
print("Warning: PID {0} has wrong number of digits".format(pid))
|
||
|
||
# print("======= DEBUG good pids = ", goodpids)
|
||
|
||
if self.crypto_type == 1:
|
||
t1_keyvec = b'QDCVEPMU675RUBSZ'
|
||
if self.magic == b'TEXtREAd':
|
||
bookkey_data = self.sect[0x0E:0x0E+16]
|
||
elif self.mobi_version < 0:
|
||
bookkey_data = self.sect[0x90:0x90+16]
|
||
else:
|
||
bookkey_data = self.sect[self.mobi_length+16:self.mobi_length+32]
|
||
pid = '00000000'
|
||
found_key = PC1(t1_keyvec, bookkey_data)
|
||
else :
|
||
# calculate the keys
|
||
drm_ptr, drm_count, drm_size, drm_flags = struct.unpack('>LLLL', self.sect[0xA8:0xA8+16])
|
||
if drm_count == 0:
|
||
raise DrmException("Encryption not initialised. Must be opened with Mobipocket Reader first.")
|
||
found_key, pid = self.parseDRM(self.sect[drm_ptr:drm_ptr+drm_size], drm_count, goodpids)
|
||
if not found_key:
|
||
raise DrmException("No key found in {0:d} PIDs tried.".format(len(goodpids)))
|
||
# kill the drm keys
|
||
self.patchSection(0, b'\0' * drm_size, drm_ptr)
|
||
# kill the drm pointers
|
||
self.patchSection(0, b'\xff' * 4 + b'\0' * 12, 0xA8)
|
||
|
||
if pid=='00000000':
|
||
print("File has default encryption, no specific key needed.")
|
||
else:
|
||
print("File is encoded with PID {0}.".format(checksumPid(pid)))
|
||
|
||
# clear the crypto type
|
||
self.patchSection(0, b'\0' * 2, 0xC)
|
||
|
||
# decrypt sections
|
||
print("Decrypting. Please wait . . .", end=' ')
|
||
mobidataList = []
|
||
mobidataList.append(self.data_file[:self.sections[1][0]])
|
||
for i in range(1, self.records+1):
|
||
data = self.loadSection(i)
|
||
extra_size = getSizeOfTrailingDataEntries(data, len(data), self.extra_data_flags)
|
||
if i%100 == 0:
|
||
print(".", end=' ')
|
||
# print "record %d, extra_size %d" %(i,extra_size)
|
||
decoded_data = PC1(found_key, data[0:len(data) - extra_size])
|
||
if i==1:
|
||
self.print_replica = (decoded_data[0:4] == b'%MOP')
|
||
mobidataList.append(decoded_data)
|
||
if extra_size > 0:
|
||
mobidataList.append(data[-extra_size:])
|
||
if self.num_sections > self.records+1:
|
||
mobidataList.append(self.data_file[self.sections[self.records+1][0]:])
|
||
self.mobi_data = b''.join(mobidataList)
|
||
print("done")
|
||
return
|
||
|
||
# pids in pidlist must be unicode
|
||
def getUnencryptedBook(infile,pidlist):
|
||
if not os.path.isfile(infile):
|
||
raise DrmException("Input File Not Found.")
|
||
book = MobiBook(infile)
|
||
book.processBook(pidlist)
|
||
return book.mobi_data
|
||
|
||
|
||
def cli_main():
|
||
argv=unicode_argv("mobidedrm.py")
|
||
progname = os.path.basename(argv[0])
|
||
if len(argv)<3 or len(argv)>4:
|
||
print("MobiDeDrm v{0:s}.\nCopyright © 2008-2020 The Dark Reverser, Apprentice Harper et al.".format(__version__))
|
||
print("Removes protection from Kindle/Mobipocket, Kindle/KF8 and Kindle/Print Replica ebooks")
|
||
print("Usage:")
|
||
print(" {0} <infile> <outfile> [<Comma separated list of PIDs to try>]".format(progname))
|
||
return 1
|
||
else:
|
||
infile = argv[1]
|
||
outfile = argv[2]
|
||
if len(argv) == 4:
|
||
pidlist = argv[3].split(',')
|
||
else:
|
||
pidlist = []
|
||
try:
|
||
stripped_file = getUnencryptedBook(infile, pidlist)
|
||
open(outfile, 'wb').write(stripped_file)
|
||
except DrmException as e:
|
||
print("MobiDeDRM v{0} Error: {1:s}".format(__version__,e.args[0]))
|
||
return 1
|
||
return 0
|
||
|
||
|
||
if __name__ == '__main__':
|
||
sys.stdout=SafeUnbuffered(sys.stdout)
|
||
sys.stderr=SafeUnbuffered(sys.stderr)
|
||
sys.exit(cli_main())
|