Posts Tagged python

Kindle DRM Cracked

Posted by on Wednesday, 23 December, 2009

Looks like somebody had a little free time and decided to crack the kindle code. They have amusingly called the python code to do so ‘swindle’

On a side note, here is an excellent website pointed out to me who does what with your privacy on e-book readers http://www.eff.org/deeplinks/2009/12/e-book-privacy

You can find the original code here http://pastie.org/753699

In case it disappears, here it is

#! /usr/bin/python
 
# unswindle.pyw, version 5-rc1
 
# To run this program install a 32-bit version of Python 2.6 from
# <http://www.python.org/download/>.  Save this script file as unswindle.pyw.
# Find and save in the same directory a copy of mobidedrm.py.  Double-click on
# unswindle.pyw.  It will run Kindle For PC.  Open the book you want to
# decrypt.  Close Kindle For PC.  A dialog will open allowing you to select the
# output file.  And you're done!
 
# Revision history:
#   1 - Initial release
#   2 - Fixes to work properly on Windows versions >XP
#   3 - Fix minor bug in path extraction
#   4 - Fix error opening threads; detect Topaz books;
#       detect unsupported versions of K4PC
#   5 - Work on new (20091222) version of K4PC
 
"""
Decrypt Kindle For PC encrypted Mobipocket books.
"""
 
__license__ = 'GPL v3'
 
import sys
import os
import re
import tempfile
import shutil
import subprocess
import struct
import hashlib
import ctypes
from ctypes import *
from ctypes.wintypes import *
import binascii
import _winreg as winreg
import Tkinter
import Tkconstants
import tkMessageBox
import tkFileDialog
import traceback
 
#
# _extrawintypes.py
 
UBYTE = c_ubyte
ULONG_PTR = POINTER(ULONG)
PULONG = ULONG_PTR
PVOID = LPVOID
LPCTSTR = LPTSTR = c_wchar_p
LPBYTE = c_char_p
SIZE_T = c_uint
SIZE_T_p = POINTER(SIZE_T)
 
#
# _ntdll.py
 
NTSTATUS = DWORD
 
ntdll = windll.ntdll
 
class PROCESS_BASIC_INFORMATION(Structure):
_fields_ = [('Reserved1', PVOID),
('PebBaseAddress', PVOID),
('Reserved2', PVOID * 2),
('UniqueProcessId', ULONG_PTR),
('Reserved3', PVOID)]
 
# NTSTATUS WINAPI NtQueryInformationProcess(
#   __in       HANDLE ProcessHandle,
#   __in       PROCESSINFOCLASS ProcessInformationClass,
#   __out      PVOID ProcessInformation,
#   __in       ULONG ProcessInformationLength,
#   __out_opt  PULONG ReturnLength
# );
NtQueryInformationProcess = ntdll.NtQueryInformationProcess
NtQueryInformationProcess.argtypes = [HANDLE, DWORD, PVOID, ULONG, PULONG]
NtQueryInformationProcess.restype = NTSTATUS
 
#
# _kernel32.py
 
INFINITE = 0xffffffff
 
CREATE_UNICODE_ENVIRONMENT = 0x00000400
DEBUG_ONLY_THIS_PROCESS = 0x00000002
DEBUG_PROCESS = 0x00000001
 
THREAD_GET_CONTEXT = 0x0008
THREAD_QUERY_INFORMATION = 0x0040
THREAD_SET_CONTEXT = 0x0010
THREAD_SET_INFORMATION = 0x0020
 
EXCEPTION_BREAKPOINT = 0x80000003
EXCEPTION_SINGLE_STEP = 0x80000004
EXCEPTION_ACCESS_VIOLATION = 0xC0000005
 
DBG_CONTINUE = 0x00010002L
DBG_EXCEPTION_NOT_HANDLED = 0x80010001L
 
EXCEPTION_DEBUG_EVENT = 1
CREATE_THREAD_DEBUG_EVENT = 2
CREATE_PROCESS_DEBUG_EVENT = 3
EXIT_THREAD_DEBUG_EVENT = 4
EXIT_PROCESS_DEBUG_EVENT = 5
LOAD_DLL_DEBUG_EVENT = 6
UNLOAD_DLL_DEBUG_EVENT = 7
OUTPUT_DEBUG_STRING_EVENT = 8
RIP_EVENT = 9
 
class DataBlob(Structure):
_fields_ = [('cbData', c_uint),
('pbData', c_void_p)]
DataBlob_p = POINTER(DataBlob)
 
class SECURITY_ATTRIBUTES(Structure):
_fields_ = [('nLength', DWORD),
('lpSecurityDescriptor', LPVOID),
('bInheritHandle', BOOL)]
LPSECURITY_ATTRIBUTES = POINTER(SECURITY_ATTRIBUTES)
 
class STARTUPINFO(Structure):
_fields_ = [('cb', DWORD),
('lpReserved', LPTSTR),
('lpDesktop', LPTSTR),
('lpTitle', LPTSTR),
('dwX', DWORD),
('dwY', DWORD),
('dwXSize', DWORD),
('dwYSize', DWORD),
('dwXCountChars', DWORD),
('dwYCountChars', DWORD),
('dwFillAttribute', DWORD),
('dwFlags', DWORD),
('wShowWindow', WORD),
('cbReserved2', WORD),
('lpReserved2', LPBYTE),
('hStdInput', HANDLE),
('hStdOutput', HANDLE),
('hStdError', HANDLE)]
LPSTARTUPINFO = POINTER(STARTUPINFO)
 
class PROCESS_INFORMATION(Structure):
_fields_ = [('hProcess', HANDLE),
('hThread', HANDLE),
('dwProcessId', DWORD),
('dwThreadId', DWORD)]
LPPROCESS_INFORMATION = POINTER(PROCESS_INFORMATION)
 
EXCEPTION_MAXIMUM_PARAMETERS = 15
class EXCEPTION_RECORD(Structure):
pass
EXCEPTION_RECORD._fields_ = [
('ExceptionCode', DWORD),
('ExceptionFlags', DWORD),
('ExceptionRecord', POINTER(EXCEPTION_RECORD)),
('ExceptionAddress', LPVOID),
('NumberParameters', DWORD),
('ExceptionInformation', ULONG_PTR * EXCEPTION_MAXIMUM_PARAMETERS)]
 
class EXCEPTION_DEBUG_INFO(Structure):
_fields_ = [('ExceptionRecord', EXCEPTION_RECORD),
('dwFirstChance', DWORD)]
 
class CREATE_THREAD_DEBUG_INFO(Structure):
_fields_ = [('hThread', HANDLE),
('lpThreadLocalBase', LPVOID),
('lpStartAddress', LPVOID)]
 
class CREATE_PROCESS_DEBUG_INFO(Structure):
_fields_ = [('hFile', HANDLE),
('hProcess', HANDLE),
('hThread', HANDLE),
('dwDebugInfoFileOffset', DWORD),
('nDebugInfoSize', DWORD),
('lpThreadLocalBase', LPVOID),
('lpStartAddress', LPVOID),
('lpImageName', LPVOID),
('fUnicode', WORD)]
 
class EXIT_THREAD_DEBUG_INFO(Structure):
_fields_ = [('dwExitCode', DWORD)]
 
class EXIT_PROCESS_DEBUG_INFO(Structure):
_fields_ = [('dwExitCode', DWORD)]
 
class LOAD_DLL_DEBUG_INFO(Structure):
_fields_ = [('hFile', HANDLE),
('lpBaseOfDll', LPVOID),
('dwDebugInfoFileOffset', DWORD),
('nDebugInfoSize', DWORD),
('lpImageName', LPVOID),
('fUnicode', WORD)]
 
class UNLOAD_DLL_DEBUG_INFO(Structure):
_fields_ = [('lpBaseOfDll', LPVOID)]
 
class OUTPUT_DEBUG_STRING_INFO(Structure):
_fields_ = [('lpDebugStringData', LPSTR),
('fUnicode', WORD),
('nDebugStringLength', WORD)]
 
class RIP_INFO(Structure):
_fields_ = [('dwError', DWORD),
('dwType', DWORD)]
 
class _U(Union):
_fields_ = [('Exception', EXCEPTION_DEBUG_INFO),
('CreateThread', CREATE_THREAD_DEBUG_INFO),
('CreateProcessInfo', CREATE_PROCESS_DEBUG_INFO),
('ExitThread', EXIT_THREAD_DEBUG_INFO),
('ExitProcess', EXIT_PROCESS_DEBUG_INFO),
('LoadDll', LOAD_DLL_DEBUG_INFO),
('UnloadDll', UNLOAD_DLL_DEBUG_INFO),
('DebugString', OUTPUT_DEBUG_STRING_INFO),
('RipInfo', RIP_INFO)]
 
class DEBUG_EVENT(Structure):
_anonymous_ = ('u',)
_fields_ = [('dwDebugEventCode', DWORD),
('dwProcessId', DWORD),
('dwThreadId', DWORD),
('u', _U)]
LPDEBUG_EVENT = POINTER(DEBUG_EVENT)
 
CONTEXT_X86 = 0x00010000
CONTEXT_i386 = CONTEXT_X86
CONTEXT_i486 = CONTEXT_X86
 
CONTEXT_CONTROL = (CONTEXT_i386 | 0x0001) # SS:SP, CS:IP, FLAGS, BP
CONTEXT_INTEGER = (CONTEXT_i386 | 0x0002) # AX, BX, CX, DX, SI, DI
CONTEXT_SEGMENTS = (CONTEXT_i386 | 0x0004) # DS, ES, FS, GS
CONTEXT_FLOATING_POINT = (CONTEXT_i386 | 0x0008L) # 387 state
CONTEXT_DEBUG_REGISTERS =  (CONTEXT_i386 | 0x0010L) # DB 0-3,6,7
CONTEXT_EXTENDED_REGISTERS =  (CONTEXT_i386 | 0x0020L)
CONTEXT_FULL = (CONTEXT_CONTROL | CONTEXT_INTEGER | CONTEXT_SEGMENTS)
CONTEXT_ALL = (CONTEXT_CONTROL | CONTEXT_INTEGER | CONTEXT_SEGMENTS |
CONTEXT_FLOATING_POINT | CONTEXT_DEBUG_REGISTERS |
CONTEXT_EXTENDED_REGISTERS)
 
SIZE_OF_80387_REGISTERS = 80
class FLOATING_SAVE_AREA(Structure):
_fields_ = [('ControlWord', DWORD),
('StatusWord', DWORD),
('TagWord', DWORD),
('ErrorOffset', DWORD),
('ErrorSelector', DWORD),
('DataOffset', DWORD),
('DataSelector', DWORD),
('RegisterArea', BYTE * SIZE_OF_80387_REGISTERS),
('Cr0NpxState', DWORD)]
 
MAXIMUM_SUPPORTED_EXTENSION = 512
class CONTEXT(Structure):
_fields_ = [('ContextFlags', DWORD),
('Dr0', DWORD),
('Dr1', DWORD),
('Dr2', DWORD),
('Dr3', DWORD),
('Dr6', DWORD),
('Dr7', DWORD),
('FloatSave', FLOATING_SAVE_AREA),
('SegGs', DWORD),
('SegFs', DWORD),
('SegEs', DWORD),
('SegDs', DWORD),
('Edi', DWORD),
('Esi', DWORD),
('Ebx', DWORD),
('Edx', DWORD),
('Ecx', DWORD),
('Eax', DWORD),
('Ebp', DWORD),
('Eip', DWORD),
('SegCs', DWORD),
('EFlags', DWORD),
('Esp', DWORD),
('SegSs', DWORD),
('ExtendedRegisters', BYTE * MAXIMUM_SUPPORTED_EXTENSION)]
LPCONTEXT = POINTER(CONTEXT)
 
class LDT_ENTRY(Structure):
_fields_ = [('LimitLow', WORD),
('BaseLow',  WORD),
('BaseMid', UBYTE),
('Flags1', UBYTE),
('Flags2', UBYTE),
('BaseHi', UBYTE)]
LPLDT_ENTRY = POINTER(LDT_ENTRY)
 
kernel32 = windll.kernel32
 
# BOOL WINAPI CloseHandle(
#   __in  HANDLE hObject
# );
CloseHandle = kernel32.CloseHandle
CloseHandle.argtypes = [HANDLE]
CloseHandle.restype = BOOL
 
# BOOL WINAPI CreateProcess(
#   __in_opt     LPCTSTR lpApplicationName,
#   __inout_opt  LPTSTR lpCommandLine,
#   __in_opt     LPSECURITY_ATTRIBUTES lpProcessAttributes,
#   __in_opt     LPSECURITY_ATTRIBUTES lpThreadAttributes,
#   __in         BOOL bInheritHandles,
#   __in         DWORD dwCreationFlags,
#   __in_opt     LPVOID lpEnvironment,
#   __in_opt     LPCTSTR lpCurrentDirectory,
#   __in         LPSTARTUPINFO lpStartupInfo,
#   __out        LPPROCESS_INFORMATION lpProcessInformation
# );
CreateProcess = kernel32.CreateProcessW
CreateProcess.argtypes = [LPCTSTR, LPTSTR, LPSECURITY_ATTRIBUTES,
LPSECURITY_ATTRIBUTES, BOOL, DWORD, LPVOID, LPCTSTR,
LPSTARTUPINFO, LPPROCESS_INFORMATION]
CreateProcess.restype = BOOL
 
# HANDLE WINAPI OpenThread(
#   __in  DWORD dwDesiredAccess,
#   __in  BOOL bInheritHandle,
#   __in  DWORD dwThreadId
# );
OpenThread = kernel32.OpenThread
OpenThread.argtypes = [DWORD, BOOL, DWORD]
OpenThread.restype = HANDLE
 
# BOOL WINAPI ContinueDebugEvent(
#   __in  DWORD dwProcessId,
#   __in  DWORD dwThreadId,
#   __in  DWORD dwContinueStatus
# );
ContinueDebugEvent = kernel32.ContinueDebugEvent
ContinueDebugEvent.argtypes = [DWORD, DWORD, DWORD]
ContinueDebugEvent.restype = BOOL
 
# BOOL WINAPI DebugActiveProcess(
#   __in  DWORD dwProcessId
# );
DebugActiveProcess = kernel32.DebugActiveProcess
DebugActiveProcess.argtypes = [DWORD]
DebugActiveProcess.restype = BOOL
 
# BOOL WINAPI GetThreadContext(
#   __in     HANDLE hThread,
#   __inout  LPCONTEXT lpContext
# );
GetThreadContext = kernel32.GetThreadContext
GetThreadContext.argtypes = [HANDLE, LPCONTEXT]
GetThreadContext.restype = BOOL
 
# BOOL WINAPI GetThreadSelectorEntry(
#   __in   HANDLE hThread,
#   __in   DWORD dwSelector,
#   __out  LPLDT_ENTRY lpSelectorEntry
# );
GetThreadSelectorEntry = kernel32.GetThreadSelectorEntry
GetThreadSelectorEntry.argtypes = [HANDLE, DWORD, LPLDT_ENTRY]
GetThreadSelectorEntry.restype = BOOL
 
# BOOL WINAPI ReadProcessMemory(
#   __in   HANDLE hProcess,
#   __in   LPCVOID lpBaseAddress,
#   __out  LPVOID lpBuffer,
#   __in   SIZE_T nSize,
#   __out  SIZE_T *lpNumberOfBytesRead
# );
ReadProcessMemory = kernel32.ReadProcessMemory
ReadProcessMemory.argtypes = [HANDLE, LPCVOID, LPVOID, SIZE_T, SIZE_T_p]
ReadProcessMemory.restype = BOOL
 
# BOOL WINAPI SetThreadContext(
#   __in  HANDLE hThread,
#   __in  const CONTEXT *lpContext
# );
SetThreadContext = kernel32.SetThreadContext
SetThreadContext.argtypes = [HANDLE, LPCONTEXT]
SetThreadContext.restype = BOOL
 
# BOOL WINAPI WaitForDebugEvent(
#   __out  LPDEBUG_EVENT lpDebugEvent,
#   __in   DWORD dwMilliseconds
# );
WaitForDebugEvent = kernel32.WaitForDebugEvent
WaitForDebugEvent.argtypes = [LPDEBUG_EVENT, DWORD]
WaitForDebugEvent.restype = BOOL
 
# BOOL WINAPI WriteProcessMemory(
#   __in   HANDLE hProcess,
#   __in   LPVOID lpBaseAddress,
#   __in   LPCVOID lpBuffer,
#   __in   SIZE_T nSize,
#   __out  SIZE_T *lpNumberOfBytesWritten
# );
WriteProcessMemory = kernel32.WriteProcessMemory
WriteProcessMemory.argtypes = [HANDLE, LPVOID, LPCVOID, SIZE_T, SIZE_T_p]
WriteProcessMemory.restype = BOOL
 
# BOOL WINAPI FlushInstructionCache(
#   __in  HANDLE hProcess,
#   __in  LPCVOID lpBaseAddress,
#   __in  SIZE_T dwSize
# );
FlushInstructionCache = kernel32.FlushInstructionCache
FlushInstructionCache.argtypes = [HANDLE, LPCVOID, SIZE_T]
FlushInstructionCache.restype = BOOL
 
#
# debugger.py
 
FLAG_TRACE_BIT = 0x100
 
class DebuggerError(Exception):
pass
 
class Debugger(object):
def __init__(self, process_info):
self.process_info = process_info
self.pid = process_info.dwProcessId
self.tid = process_info.dwThreadId
self.hprocess = process_info.hProcess
self.hthread = process_info.hThread
self._threads = {self.tid: self.hthread}
self._processes = {self.pid: self.hprocess}
self._bps = {}
self._inactive = {}
 
def read_process_memory(self, addr, size=None, type=str):
if issubclass(type, basestring):
buf = ctypes.create_string_buffer(size)
ref = buf
else:
size = ctypes.sizeof(type)
buf = type()
ref = byref(buf)
copied = SIZE_T(0)
rv = ReadProcessMemory(self.hprocess, addr, ref, size, byref(copied))
if not rv:
addr = getattr(addr, 'value', addr)
raise DebuggerError("could not read memory @ 0x%08x" % (addr,))
if copied.value != size:
raise DebuggerError("insufficient memory read")
if issubclass(type, basestring):
return buf.raw
return buf
 
def set_bp(self, addr, callback, bytev=None):
hprocess = self.hprocess
if bytev is None:
byte = self.read_process_memory(addr, type=ctypes.c_byte)
bytev = byte.value
else:
byte = ctypes.c_byte(0)
self._bps[addr] = (bytev, callback)
byte.value = 0xcc
copied = SIZE_T(0)
rv = WriteProcessMemory(hprocess, addr, byref(byte), 1, byref(copied))
if not rv:
addr = getattr(addr, 'value', addr)
raise DebuggerError("could not write memory @ 0x%08x" % (addr,))
if copied.value != 1:
raise DebuggerError("insufficient memory written")
rv = FlushInstructionCache(hprocess, None, 0)
if not rv:
raise DebuggerError("could not flush instruction cache")
return
 
def _restore_bps(self):
for addr, (bytev, callback) in self._inactive.items():
self.set_bp(addr, callback, bytev=bytev)
self._inactive.clear()
 
def _handle_bp(self, addr):
hprocess = self.hprocess
hthread = self.hthread
bytev, callback = self._inactive[addr] = self._bps.pop(addr)
byte = ctypes.c_byte(bytev)
copied = SIZE_T(0)
rv = WriteProcessMemory(hprocess, addr, byref(byte), 1, byref(copied))
if not rv:
raise DebuggerError("could not write memory")
if copied.value != 1:
raise DebuggerError("insufficient memory written")
rv = FlushInstructionCache(hprocess, None, 0)
if not rv:
raise DebuggerError("could not flush instruction cache")
context = CONTEXT(ContextFlags=CONTEXT_FULL)
rv = GetThreadContext(hthread, byref(context))
if not rv:
raise DebuggerError("could not get thread context")
context.Eip = addr
callback(self, context)
context.EFlags |= FLAG_TRACE_BIT
rv = SetThreadContext(hthread, byref(context))
if not rv:
raise DebuggerError("could not set thread context")
return
 
def _get_peb_address(self):
hthread = self.hthread
hprocess = self.hprocess
try:
pbi = PROCESS_BASIC_INFORMATION()
rv = NtQueryInformationProcess(hprocess, 0, byref(pbi),
sizeof(pbi), None)
if rv != 0:
raise DebuggerError("could not query process information")
return pbi.PebBaseAddress
except DebuggerError:
pass
try:
context = CONTEXT(ContextFlags=CONTEXT_FULL)
rv = GetThreadContext(hthread, byref(context))
if not rv:
raise DebuggerError("could not get thread context")
entry = LDT_ENTRY()
rv = GetThreadSelectorEntry(hthread, context.SegFs, byref(entry))
if not rv:
raise DebuggerError("could not get selector entry")
low, mid, high = entry.BaseLow, entry.BaseMid, entry.BaseHi
fsbase = low | (mid << 16) | (high << 24)
pebaddr = self.read_process_memory(fsbase + 0x30, type=c_voidp)
return pebaddr.value
except DebuggerError:
pass
return 0x7ffdf000
 
def get_base_address(self):
addr = self._get_peb_address() + (2 * 4)
baseaddr = self.read_process_memory(addr, type=c_voidp)
return baseaddr.value
 
def main_loop(self):
event = DEBUG_EVENT()
finished = False
while not finished:
rv = WaitForDebugEvent(byref(event), INFINITE)
if not rv:
raise DebuggerError("could not get debug event")
self.pid = pid = event.dwProcessId
self.tid = tid = event.dwThreadId
self.hprocess = self._processes.get(pid, None)
self.hthread = self._threads.get(tid, None)
status = DBG_CONTINUE
evid = event.dwDebugEventCode
if evid == EXCEPTION_DEBUG_EVENT:
first = event.Exception.dwFirstChance
record = event.Exception.ExceptionRecord
exid = record.ExceptionCode
flags = record.ExceptionFlags
addr = record.ExceptionAddress
if exid == EXCEPTION_BREAKPOINT:
if addr in self._bps:
self._handle_bp(addr)
elif exid == EXCEPTION_SINGLE_STEP:
self._restore_bps()
else:
status = DBG_EXCEPTION_NOT_HANDLED
elif evid == LOAD_DLL_DEBUG_EVENT:
hfile = event.LoadDll.hFile
if hfile is not None:
rv = CloseHandle(hfile)
if not rv:
raise DebuggerError("error closing file handle")
elif evid == CREATE_THREAD_DEBUG_EVENT:
info = event.CreateThread
self.hthread = info.hThread
self._threads[tid] = self.hthread
elif evid == EXIT_THREAD_DEBUG_EVENT:
hthread = self._threads.pop(tid, None)
if hthread is not None:
rv = CloseHandle(hthread)
if not rv:
raise DebuggerError("error closing thread handle")
elif evid == CREATE_PROCESS_DEBUG_EVENT:
info = event.CreateProcessInfo
self.hprocess = info.hProcess
self._processes[pid] = self.hprocess
elif evid == EXIT_PROCESS_DEBUG_EVENT:
hprocess = self._processes.pop(pid, None)
if hprocess is not None:
rv = CloseHandle(hprocess)
if not rv:
raise DebuggerError("error closing process handle")
if pid == self.process_info.dwProcessId:
finished = True
rv = ContinueDebugEvent(pid, tid, status)
if not rv:
raise DebuggerError("could not continue debug")
return True
 
#
# unswindle.py
 
KINDLE_REG_KEY = \
r'Software\Classes\Amazon.KindleForPC.content\shell\open\command'
 
class UnswindleError(Exception):
pass
 
class PC1KeyGrabber(object):
HOOKS = {
'b9f7e422094b8c8966a0e881e6358116e03e5b7b': {
0x004a719d: '_no_debugger_here',
0x005a795b: '_no_debugger_here',
0x0054f7e0: '_get_pc1_pid',
0x004f9c79: '_get_book_path',
},
'd5124ee20dab10e44b41a039363f6143725a5417': {
0x0041150d: '_i_like_wine',
0x004a681d: '_no_debugger_here',
0x005a438b: '_no_debugger_here',
0x0054c9e0: '_get_pc1_pid',
0x004f8ac9: '_get_book_path',
},
}
 
@classmethod
def supported_version(cls, hexdigest):
return (hexdigest in cls.HOOKS)
 
def _taddr(self, addr):
return (addr - 0x00400000) + self.baseaddr
 
def __init__(self, debugger, hexdigest):
self.book_path = None
self.book_pid = None
self.baseaddr = debugger.get_base_address()
hooks = self.HOOKS[hexdigest]
for addr, mname in hooks.items():
debugger.set_bp(self._taddr(addr), getattr(self, mname))
 
def _i_like_wine(self, debugger, context):
context.Eax = 1
return
 
def _no_debugger_here(self, debugger, context):
context.Eip += 2
context.Eax = 0
return
 
def _get_book_path(self, debugger, context):
addr = debugger.read_process_memory(context.Esp, type=ctypes.c_voidp)
try:
path = debugger.read_process_memory(addr, 4096)
except DebuggerError:
pgrest = 0x1000 - (addr.value & 0xfff)
path = debugger.read_process_memory(addr, pgrest)
path = path.decode('utf-16', 'ignore')
if u'\0' in path:
path = path[:path.index(u'\0')]
if path[-4:].lower() not in ('.prc', '.pdb', '.mobi'):
return
self.book_path = path
 
def _get_pc1_pid(self, debugger, context):
addr = context.Esp + ctypes.sizeof(ctypes.c_voidp)
addr = debugger.read_process_memory(addr, type=ctypes.c_char_p)
pid = debugger.read_process_memory(addr, 8)
pid = self._checksum_pid(pid)
self.book_pid = pid
 
def _checksum_pid(self, 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
 
class Unswindler(object):
def __init__(self):
self._exepath = self._get_exe_path()
self._hexdigest = self._get_hexdigest()
self._exedir = os.path.dirname(self._exepath)
self._mobidedrmpath = self._get_mobidedrm_path()
 
def _get_mobidedrm_path(self):
basedir = sys.modules[self.__module__].__file__
basedir = os.path.dirname(basedir)
for basename in ('mobidedrm', 'mobidedrm.py', 'mobidedrm.pyw'):
path = os.path.join(basedir, basename)
if os.path.isfile(path):
return path
raise UnswindleError("could not locate MobiDeDRM script")
 
def _get_exe_path(self):
path = None
for root in (winreg.HKEY_CURRENT_USER, winreg.HKEY_LOCAL_MACHINE):
try:
regkey = winreg.OpenKey(root, KINDLE_REG_KEY)
path = winreg.QueryValue(regkey, None)
break
except WindowsError:
pass
else:
raise UnswindleError("Kindle For PC installation not found")
if '"' in path:
path = re.search(r'"(.*?)"', path).group(1)
return path
 
def _get_hexdigest(self):
path = self._exepath
sha1 = hashlib.sha1()
with open(path, 'rb') as f:
data = f.read(4096)
while data:
sha1.update(data)
data = f.read(4096)
hexdigest = sha1.hexdigest()
if not PC1KeyGrabber.supported_version(hexdigest):
raise UnswindleError("Unsupported version of Kindle For PC")
return hexdigest
 
def _is_topaz(self, path):
with open(path, 'rb') as f:
magic = f.read(4)
if magic == 'TPZ0':
return True
return False
 
def get_book(self):
creation_flags = (CREATE_UNICODE_ENVIRONMENT |
DEBUG_PROCESS |
DEBUG_ONLY_THIS_PROCESS)
startup_info = STARTUPINFO()
process_info = PROCESS_INFORMATION()
path = pid = None
try:
rv = CreateProcess(self._exepath, None, None, None, False,
creation_flags, None, self._exedir,
byref(startup_info), byref(process_info))
if not rv:
raise UnswindleError("failed to launch Kindle For PC")
debugger = Debugger(process_info)
grabber = PC1KeyGrabber(debugger, self._hexdigest)
debugger.main_loop()
path = grabber.book_path
pid = grabber.book_pid
finally:
if process_info.hThread is not None:
CloseHandle(process_info.hThread)
if process_info.hProcess is not None:
CloseHandle(process_info.hProcess)
if path is None:
raise UnswindleError("failed to determine book path")
if self._is_topaz(path):
raise UnswindleError("cannot decrypt Topaz format book")
if pid is None:
raise UnswindleError("failed to determine book PID")
return (path, pid)
 
def decrypt_book(self, inpath, outpath, pid):
# darkreverser didn't protect mobidedrm's script execution to allow
# importing, so we have to just run it in a subprocess
with tempfile.NamedTemporaryFile(delete=False) as tmpf:
tmppath = tmpf.name
args = [sys.executable, self._mobidedrmpath, inpath, tmppath, pid]
mobidedrm = subprocess.Popen(args, stderr=subprocess.STDOUT,
stdout=subprocess.PIPE,
universal_newlines=True)
output = mobidedrm.communicate()[0]
if not output.endswith("done\n"):
try:
os.remove(tmppath)
except OSError:
pass
raise UnswindleError("problem running MobiDeDRM:\n" + output)
shutil.move(tmppath, outpath)
return
 
class ExceptionDialog(Tkinter.Frame):
def __init__(self, root, text):
Tkinter.Frame.__init__(self, root, border=5)
label = Tkinter.Label(self, text="Unexpected error:",
anchor=Tkconstants.W, justify=Tkconstants.LEFT)
label.pack(fill=Tkconstants.X, expand=0)
self.text = Tkinter.Text(self)
self.text.pack(fill=Tkconstants.BOTH, expand=1)
self.text.insert(Tkconstants.END, text)
 
def gui_main(argv=sys.argv):
root = Tkinter.Tk()
root.withdraw()
progname = os.path.basename(argv[0])
try:
unswindler = Unswindler()
inpath, pid = unswindler.get_book()
outpath = tkFileDialog.asksaveasfilename(
parent=None, title='Select unencrypted Mobipocket file to produce',
defaultextension='.mobi', filetypes=[('MOBI files', '.mobi'),
('All files', '.*')])
if not outpath:
return 0
unswindler.decrypt_book(inpath, outpath, pid)
except UnswindleError, e:
tkMessageBox.showerror("Unswindle For PC", "Error: " + str(e))
return 1
except Exception:
root.wm_state('normal')
root.title('Unswindle For PC')
text = traceback.format_exc()
ExceptionDialog(root, text).pack(fill=Tkconstants.BOTH, expand=1)
root.mainloop()
return 1
 
def cli_main(argv=sys.argv):
progname = os.path.basename(argv[0])
args = argv[1:]
if len(args) != 1:
sys.stderr.write("usage: %s OUTFILE\n" % (progname,))
return 1
outpath = args[0]
unswindler = Unswindler()
inpath, pid = unswindler.get_book()
unswindler.decrypt_book(inpath, outpath, pid)
return 0
 
if __name__ == '__main__':
sys.exit(gui_main())

Learning python

Posted by on Tuesday, 7 April, 2009

Learning Python is very easy with this quick and easy python tutorial going over the basics.