mirror of
https://github.com/noDRM/DeDRM_tools.git
synced 2024-08-21 16:46:09 +06:00
406 lines
16 KiB
Python
406 lines
16 KiB
Python
#!/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 -> '')
|
|
|
|
__version__ = '0.28'
|
|
|
|
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
|
|
|
|
class DrmException(Exception):
|
|
pass
|
|
|
|
|
|
#
|
|
# MobiBook Utility Routines
|
|
#
|
|
|
|
# Implementation of Pukall Cipher 1
|
|
def PC1(key, src, decryption=True):
|
|
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):
|
|
# initial sanity check on file
|
|
self.data_file = file(infile, 'rb').read()
|
|
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])
|
|
|
|
if self.magic == 'TEXtREAd':
|
|
print "Book has format: ", self.magic
|
|
self.extra_data_flags = 0
|
|
self.mobi_length = 0
|
|
self.mobi_version = -1
|
|
self.meta_array = {}
|
|
return
|
|
self.mobi_length, = struct.unpack('>L',self.sect[0x14:0x18])
|
|
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.mobi_version < 7:
|
|
# multibyte utf8 data is included in the encryption for mobi_version 6 and below
|
|
# 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
|
|
|
|
def getBookTitle(self):
|
|
title = ''
|
|
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 title == '':
|
|
title = self.header[:32]
|
|
title = title.split("\0")[0]
|
|
return title
|
|
|
|
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 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."
|
|
return self.data_file
|
|
if crypto_type != 2 and crypto_type != 1:
|
|
raise DrmException("Cannot decode unknown Mobipocket encryption type %d" % crypto_type)
|
|
|
|
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. Most likely the correct PID has not been given.")
|
|
# 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 . . .",
|
|
new_data = 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)
|
|
new_data += PC1(found_key, data[0:len(data) - extra_size])
|
|
if extra_size > 0:
|
|
new_data += data[-extra_size:]
|
|
if self.num_sections > self.records+1:
|
|
new_data += self.data_file[self.sections[self.records+1][0]:]
|
|
self.data_file = new_data
|
|
print "done"
|
|
return self.data_file
|
|
|
|
def getUnencryptedBook(infile,pid):
|
|
if not os.path.isfile(infile):
|
|
raise DrmException('Input File Not Found')
|
|
book = MobiBook(infile)
|
|
return book.processBook([pid])
|
|
|
|
def getUnencryptedBookWithList(infile,pidlist):
|
|
if not os.path.isfile(infile):
|
|
raise DrmException('Input File Not Found')
|
|
book = MobiBook(infile)
|
|
return book.processBook(pidlist)
|
|
|
|
def main(argv=sys.argv):
|
|
print ('MobiDeDrm v%(__version__)s. '
|
|
'Copyright 2008-2010 The Dark Reverser.' % globals())
|
|
if len(argv)<3 or len(argv)>4:
|
|
print "Removes protection from Mobipocket books"
|
|
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)
|
|
file(outfile, 'wb').write(stripped_file)
|
|
except DrmException, e:
|
|
print "Error: %s" % e
|
|
return 1
|
|
return 0
|
|
|
|
|
|
if __name__ == "__main__":
|
|
sys.exit(main())
|