Mirrors
/
DeDRM_tools
mirror of https://github.com/noDRM/DeDRM_tools.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
DeDRM_tools/Calibre_Plugins/k4mobidedrm_plugin/mobidedrm.py

461 lines
19 KiB
Python
Raw Normal View History

tools v5.4.1
2012-11-20 06:28:12 -07:00
#!/usr/bin/python
#
# 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
__version__ = '0.37'
import sys
class Unbuffered:
def __init__(self, stream):
self.stream = stream
def write(self, data):
self.stream.write(data)
self.stream.flush()
def __getattr__(self, attr):
return getattr(self.stream, attr)
sys.stdout=Unbuffered(sys.stdout)
import os
import struct
import binascii
from alfcrypto import Pukall_Cipher
class DrmException(Exception):
pass
#
# MobiBook Utility Routines
#
# Implementation of Pukall Cipher 1
def PC1(key, src, decryption=True):
return Pukall_Cipher().PC1(key,src,decryption)
# sum1 = 0;
# sum2 = 0;
# keyXorVal = 0;
# if len(key)!=16:
# print "Bad key length!"
# return None
# wkey = []
# for i in xrange(8):
# wkey.append(ord(key[i*2])<<8 | ord(key[i*2+1]))
# dst = ""
# for i in xrange(len(src)):
# temp1 = 0;
# byteXorVal = 0;
# for j in xrange(8):
# temp1 ^= wkey[j]
# sum2 = (sum2+j)*20021 + sum1
# sum1 = (temp1*346)&0xFFFF
# sum2 = (sum2+sum1)&0xFFFF
# temp1 = (temp1*20021+1)&0xFFFF
# byteXorVal ^= temp1 ^ sum2
# curByte = ord(src[i])
# if not decryption:
# keyXorVal = curByte * 257;
# curByte = ((curByte ^ (byteXorVal >> 8)) ^ byteXorVal) & 0xFF
# if decryption:
# keyXorVal = curByte * 257;
# for j in xrange(8):
# wkey[j] ^= keyXorVal;
# dst+=chr(curByte)
# return dst
def checksumPid(s):
letters = "ABCDEFGHIJKLMNPQRSTUVWXYZ123456789"
crc = (~binascii.crc32(s,-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
def getSizeOfTrailingDataEntries(ptr, size, flags):
def getSizeOfTrailingDataEntry(ptr, size):
bitpos, result = 0, 0
if size <= 0:
return result
while True:
v = ord(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 += (ord(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 __init__(self, infile, announce = True):
if announce:
print ('MobiDeDrm v%(__version__)s. '
'Copyright 2008-2012 The Dark Reverser et al.' % globals())
# initial sanity check on file
self.data_file = file(infile, 'rb').read()
self.mobi_data = ''
self.header = self.data_file[0:78]
if self.header[0x3C:0x3C+8] != 'BOOKMOBI' and self.header[0x3C:0x3C+8] != '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 xrange(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])
if self.magic == 'TEXtREAd':
print "Book has format: ", self.magic
self.extra_data_flags = 0
self.mobi_length = 0
self.mobi_codepage = 1252
self.mobi_version = -1
self.meta_array = {}
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 = %d, length = %d" %(self.mobi_version, self.mobi_length)
self.extra_data_flags = 0
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 = %d" % 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
self.meta_array = {}
try:
exth_flag, = struct.unpack('>L', self.sect[0x80:0x84])
exth = 'NONE'
if exth_flag & 0x40:
exth = self.sect[16 + self.mobi_length:]
if (len(exth) >= 4) and (exth[:4] == 'EXTH'):
nitems, = struct.unpack('>I', exth[8:12])
pos = 12
for i in xrange(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, "\144", 16 + self.mobi_length + pos + 8)
elif type == 404 and size == 9:
# make sure text to speech is enabled
self.patchSection(0, "\0", 16 + self.mobi_length + pos + 8)
# print type, size, content, content.encode('hex')
pos += size
except:
self.meta_array = {}
pass
self.print_replica = False
def getBookTitle(self):
codec_map = {
1252 : 'windows-1252',
65001 : 'utf-8',
}
title = ''
codec = 'windows-1252'
if self.magic == '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 == '':
title = self.header[:32]
title = title.split("\0")[0]
return unicode(title, codec).encode('utf-8')
def getPIDMetaInfo(self):
rec209 = ''
token = ''
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 xrange(0,len(data),5):
val, = struct.unpack('>I',data[i+1:i+5])
sval = self.meta_array.get(val,'')
token += sval
return rec209, token
def patch(self, off, new):
self.data_file = self.data_file[:off] + new + self.data_file[off+len(new):]
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)
def parseDRM(self, data, count, pidlist):
found_key = None
keyvec1 = "\x72\x38\x33\xB0\xB4\xF2\xE3\xCA\xDF\x09\x01\xD6\xE2\xE0\x3F\x96"
for pid in pidlist:
bigpid = pid.ljust(16,'\0')
temp_key = PC1(keyvec1, bigpid, False)
temp_key_sum = sum(map(ord,temp_key)) & 0xff
found_key = None
for i in xrange(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(map(ord,temp_key)) & 0xff
for i in xrange(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 getMobiFile(self, outpath):
file(outpath,'wb').write(self.mobi_data)
def getMobiVersion(self):
return self.mobi_version
def getPrintReplica(self):
return self.print_replica
def processBook(self, pidlist):
crypto_type, = struct.unpack('>H', self.sect[0xC:0xC+2])
print 'Crypto Type is: ', 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] == '%MOP')
self.mobi_data = self.data_file
return
if crypto_type != 2 and crypto_type != 1:
raise DrmException("Cannot decode unknown Mobipocket encryption type %d" % crypto_type)
if 406 in self.meta_array:
data406 = self.meta_array[406]
val406, = struct.unpack('>Q',data406)
if val406 != 0:
raise DrmException("Cannot decode library or rented ebooks.")
goodpids = []
for pid in pidlist:
if len(pid)==10:
if checksumPid(pid[0:-2]) != pid:
print "Warning: PID " + pid + " has incorrect checksum, should have been "+checksumPid(pid[0:-2])
goodpids.append(pid[0:-2])
elif len(pid)==8:
goodpids.append(pid)
if self.crypto_type == 1:
t1_keyvec = "QDCVEPMU675RUBSZ"
if self.magic == '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("Not yet initialised with PID. 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 " + str(len(goodpids)) + " keys tried. Read the FAQs at Alf's blog. Only if none apply, report this failure for help.")
# kill the drm keys
self.patchSection(0, "\0" * drm_size, drm_ptr)
# kill the drm pointers
self.patchSection(0, "\xff" * 4 + "\0" * 12, 0xA8)
if pid=="00000000":
print "File has default encryption, no specific PID."
else:
print "File is encoded with PID "+checksumPid(pid)+"."
# clear the crypto type
self.patchSection(0, "\0" * 2, 0xC)
# decrypt sections
print "Decrypting. Please wait . . .",
mobidataList = []
mobidataList.append(self.data_file[:self.sections[1][0]])
for i in xrange(1, self.records+1):
data = self.loadSection(i)
extra_size = getSizeOfTrailingDataEntries(data, len(data), self.extra_data_flags)
if i%100 == 0:
print ".",
# 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] == '%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 = "".join(mobidataList)
print "done"
return
def getUnencryptedBook(infile,pid,announce=True):
if not os.path.isfile(infile):
raise DrmException('Input File Not Found')
book = MobiBook(infile,announce)
book.processBook([pid])
return book.mobi_data
def getUnencryptedBookWithList(infile,pidlist,announce=True):
if not os.path.isfile(infile):
raise DrmException('Input File Not Found')
book = MobiBook(infile, announce)
book.processBook(pidlist)
return book.mobi_data
def main(argv=sys.argv):
print ('MobiDeDrm v%(__version__)s. '
'Copyright 2008-2012 The Dark Reverser et al.' % globals())
if len(argv)<3 or len(argv)>4:
print "Removes protection from Kindle/Mobipocket, Kindle/KF8 and Kindle/Print Replica ebooks"
print "Usage:"
print " %s <infile> <outfile> [<Comma separated list of PIDs to try>]" % sys.argv[0]
return 1
else:
infile = argv[1]
outfile = argv[2]
if len(argv) is 4:
pidlist = argv[3].split(',')
else:
pidlist = {}
try:
stripped_file = getUnencryptedBookWithList(infile, pidlist, False)
file(outfile, 'wb').write(stripped_file)
except DrmException, e:
print "Error: %s" % e
return 1
return 0
if __name__ == "__main__":
sys.exit(main())