mirror of
https://github.com/apprenticeharper/DeDRM_tools
synced 2024-12-26 09:58:55 +01:00
2328 lines
76 KiB
Python
Executable file
2328 lines
76 KiB
Python
Executable file
#!/usr/bin/env python3
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# -*- coding: utf-8 -*-
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# ineptpdf.py
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# Copyright © 2009-2020 by i♥cabbages, Apprentice Harper et al.
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# Released under the terms of the GNU General Public Licence, version 3
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# <http://www.gnu.org/licenses/>
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# Revision history:
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# 1 - Initial release
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# 2 - Improved determination of key-generation algorithm
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# 3 - Correctly handle PDF >=1.5 cross-reference streams
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# 4 - Removal of ciando's personal ID
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# 5 - Automated decryption of a complete directory
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# 6.1 - backward compatibility for 1.7.1 and old adeptkey.der
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# 7 - Get cross reference streams and object streams working for input.
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# Not yet supported on output but this only effects file size,
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# not functionality. (anon2)
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# 7.1 - Correct a problem when an old trailer is not followed by startxref
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# 7.2 - Correct malformed Mac OS resource forks for Stanza (anon2)
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# - Support for cross ref streams on output (decreases file size)
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# 7.3 - Correct bug in trailer with cross ref stream that caused the error
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# "The root object is missing or invalid" in Adobe Reader. (anon2)
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# 7.4 - Force all generation numbers in output file to be 0, like in v6.
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# Fallback code for wrong xref improved (search till last trailer
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# instead of first) (anon2)
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# 7.5 - allow support for OpenSSL to replace pycrypto on all platforms
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# implemented ARC4 interface to OpenSSL
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# fixed minor typos
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# 7.6 - backported AES and other fixes from version 8.4.48
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# 7.7 - On Windows try PyCrypto first and OpenSSL next
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# 7.8 - Modify interface to allow use of import
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# 7.9 - Bug fix for some session key errors when len(bookkey) > length required
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# 7.10 - Various tweaks to fix minor problems.
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# 7.11 - More tweaks to fix minor problems.
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# 7.12 - Revised to allow use in calibre plugins to eliminate need for duplicate code
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# 7.13 - Fixed erroneous mentions of ineptepub
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# 7.14 - moved unicode_argv call inside main for Windows DeDRM compatibility
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# 8.0 - Work if TkInter is missing
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# 8.0.1 - Broken Metadata fix.
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# 8.0.2 - Add additional check on DER file sanity
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# 8.0.3 - Remove erroneous check on DER file sanity
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# 8.0.4 - Completely remove erroneous check on DER file sanity
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# 8.0.5 - Do not process DRM-free documents
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# 8.0.6 - Replace use of float by Decimal for greater precision, and import tkFileDialog
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# 9.0.0 - Add Python 3 compatibility for calibre 5
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"""
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Decrypts Adobe ADEPT-encrypted PDF files.
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"""
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__license__ = 'GPL v3'
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__version__ = "9.0.0"
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import codecs
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import sys
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import os
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import re
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import zlib
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import struct
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import hashlib
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from io import BytesIO
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from decimal import Decimal
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import itertools
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import xml.etree.ElementTree as etree
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# Wrap a stream so that output gets flushed immediately
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# and also make sure that any unicode strings get
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# encoded using "replace" before writing them.
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class SafeUnbuffered:
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def __init__(self, stream):
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self.stream = stream
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self.encoding = stream.encoding
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if self.encoding == None:
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self.encoding = "utf-8"
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def write(self, data):
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if isinstance(data, str):
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data = data.encode(self.encoding,"replace")
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self.stream.buffer.write(data)
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self.stream.buffer.flush()
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def __getattr__(self, attr):
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return getattr(self.stream, attr)
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iswindows = sys.platform.startswith('win')
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isosx = sys.platform.startswith('darwin')
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def unicode_argv():
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if iswindows:
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# Uses shell32.GetCommandLineArgvW to get sys.argv as a list of Unicode
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# strings.
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# Versions 2.x of Python don't support Unicode in sys.argv on
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# Windows, with the underlying Windows API instead replacing multi-byte
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# characters with '?'.
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from ctypes import POINTER, byref, cdll, c_int, windll
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from ctypes.wintypes import LPCWSTR, LPWSTR
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GetCommandLineW = cdll.kernel32.GetCommandLineW
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GetCommandLineW.argtypes = []
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GetCommandLineW.restype = LPCWSTR
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CommandLineToArgvW = windll.shell32.CommandLineToArgvW
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CommandLineToArgvW.argtypes = [LPCWSTR, POINTER(c_int)]
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CommandLineToArgvW.restype = POINTER(LPWSTR)
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cmd = GetCommandLineW()
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argc = c_int(0)
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argv = CommandLineToArgvW(cmd, byref(argc))
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if argc.value > 0:
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# Remove Python executable and commands if present
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start = argc.value - len(sys.argv)
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return [argv[i] for i in
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range(start, argc.value)]
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return ["ineptpdf.py"]
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else:
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argvencoding = sys.stdin.encoding or "utf-8"
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return [arg if isinstance(arg, str) else str(arg, argvencoding) for arg in sys.argv]
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class ADEPTError(Exception):
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pass
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import hashlib
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def SHA256(message):
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ctx = hashlib.sha256()
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ctx.update(message)
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return ctx.digest()
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def _load_crypto_libcrypto():
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from ctypes import CDLL, POINTER, c_void_p, c_char_p, c_int, c_long, \
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Structure, c_ulong, create_string_buffer, cast
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from ctypes.util import find_library
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if sys.platform.startswith('win'):
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libcrypto = find_library('libeay32')
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else:
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libcrypto = find_library('crypto')
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if libcrypto is None:
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raise ADEPTError('libcrypto not found')
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libcrypto = CDLL(libcrypto)
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AES_MAXNR = 14
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RSA_NO_PADDING = 3
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c_char_pp = POINTER(c_char_p)
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c_int_p = POINTER(c_int)
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class AES_KEY(Structure):
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_fields_ = [('rd_key', c_long * (4 * (AES_MAXNR + 1))), ('rounds', c_int)]
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AES_KEY_p = POINTER(AES_KEY)
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class RC4_KEY(Structure):
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_fields_ = [('x', c_int), ('y', c_int), ('box', c_int * 256)]
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RC4_KEY_p = POINTER(RC4_KEY)
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class RSA(Structure):
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pass
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RSA_p = POINTER(RSA)
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def F(restype, name, argtypes):
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func = getattr(libcrypto, name)
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func.restype = restype
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func.argtypes = argtypes
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return func
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AES_cbc_encrypt = F(None, 'AES_cbc_encrypt',[c_char_p, c_char_p, c_ulong, AES_KEY_p, c_char_p,c_int])
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AES_set_decrypt_key = F(c_int, 'AES_set_decrypt_key',[c_char_p, c_int, AES_KEY_p])
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RC4_set_key = F(None,'RC4_set_key',[RC4_KEY_p, c_int, c_char_p])
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RC4_crypt = F(None,'RC4',[RC4_KEY_p, c_int, c_char_p, c_char_p])
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d2i_RSAPrivateKey = F(RSA_p, 'd2i_RSAPrivateKey',
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[RSA_p, c_char_pp, c_long])
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RSA_size = F(c_int, 'RSA_size', [RSA_p])
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RSA_private_decrypt = F(c_int, 'RSA_private_decrypt',
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[c_int, c_char_p, c_char_p, RSA_p, c_int])
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RSA_free = F(None, 'RSA_free', [RSA_p])
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class RSA(object):
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def __init__(self, der):
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buf = create_string_buffer(der)
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pp = c_char_pp(cast(buf, c_char_p))
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rsa = self._rsa = d2i_RSAPrivateKey(None, pp, len(der))
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if rsa is None:
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raise ADEPTError('Error parsing ADEPT user key DER')
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def decrypt(self, from_):
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rsa = self._rsa
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to = create_string_buffer(RSA_size(rsa))
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dlen = RSA_private_decrypt(len(from_), from_, to, rsa,
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RSA_NO_PADDING)
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if dlen < 0:
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raise ADEPTError('RSA decryption failed')
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return to[1:dlen]
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def __del__(self):
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if self._rsa is not None:
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RSA_free(self._rsa)
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self._rsa = None
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class ARC4(object):
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@classmethod
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def new(cls, userkey):
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self = ARC4()
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self._blocksize = len(userkey)
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key = self._key = RC4_KEY()
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RC4_set_key(key, self._blocksize, userkey)
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return self
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def __init__(self):
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self._blocksize = 0
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self._key = None
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def decrypt(self, data):
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out = create_string_buffer(len(data))
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RC4_crypt(self._key, len(data), data, out)
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return out.raw
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class AES(object):
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MODE_CBC = 0
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@classmethod
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def new(cls, userkey, mode, iv):
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self = AES()
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self._blocksize = len(userkey)
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# mode is ignored since CBCMODE is only thing supported/used so far
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self._mode = mode
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if (self._blocksize != 16) and (self._blocksize != 24) and (self._blocksize != 32) :
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raise ADEPTError('AES improper key used')
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return
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keyctx = self._keyctx = AES_KEY()
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self._iv = iv
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rv = AES_set_decrypt_key(userkey, len(userkey) * 8, keyctx)
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if rv < 0:
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raise ADEPTError('Failed to initialize AES key')
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return self
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def __init__(self):
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self._blocksize = 0
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self._keyctx = None
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self._iv = 0
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self._mode = 0
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def decrypt(self, data):
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out = create_string_buffer(len(data))
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rv = AES_cbc_encrypt(data, out, len(data), self._keyctx, self._iv, 0)
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if rv == 0:
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raise ADEPTError('AES decryption failed')
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return out.raw
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return (ARC4, RSA, AES)
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def _load_crypto_pycrypto():
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from Crypto.PublicKey import RSA as _RSA
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from Crypto.Cipher import ARC4 as _ARC4
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from Crypto.Cipher import AES as _AES
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# ASN.1 parsing code from tlslite
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class ASN1Error(Exception):
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pass
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class ASN1Parser(object):
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class Parser(object):
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def __init__(self, bytes):
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self.bytes = bytes
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self.index = 0
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def get(self, length):
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if self.index + length > len(self.bytes):
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raise ASN1Error("Error decoding ASN.1")
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x = 0
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for count in range(length):
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x <<= 8
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x |= self.bytes[self.index]
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self.index += 1
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return x
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def getFixBytes(self, lengthBytes):
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bytes = self.bytes[self.index : self.index+lengthBytes]
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self.index += lengthBytes
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return bytes
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def getVarBytes(self, lengthLength):
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lengthBytes = self.get(lengthLength)
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return self.getFixBytes(lengthBytes)
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def getFixList(self, length, lengthList):
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l = [0] * lengthList
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for x in range(lengthList):
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l[x] = self.get(length)
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return l
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def getVarList(self, length, lengthLength):
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lengthList = self.get(lengthLength)
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if lengthList % length != 0:
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raise ASN1Error("Error decoding ASN.1")
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lengthList = int(lengthList/length)
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l = [0] * lengthList
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for x in range(lengthList):
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l[x] = self.get(length)
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return l
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def startLengthCheck(self, lengthLength):
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self.lengthCheck = self.get(lengthLength)
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self.indexCheck = self.index
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def setLengthCheck(self, length):
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self.lengthCheck = length
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self.indexCheck = self.index
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def stopLengthCheck(self):
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if (self.index - self.indexCheck) != self.lengthCheck:
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raise ASN1Error("Error decoding ASN.1")
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def atLengthCheck(self):
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if (self.index - self.indexCheck) < self.lengthCheck:
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return False
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elif (self.index - self.indexCheck) == self.lengthCheck:
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return True
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else:
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raise ASN1Error("Error decoding ASN.1")
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def __init__(self, bytes):
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p = self.Parser(bytes)
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p.get(1)
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self.length = self._getASN1Length(p)
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self.value = p.getFixBytes(self.length)
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def getChild(self, which):
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p = self.Parser(self.value)
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for x in range(which+1):
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markIndex = p.index
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p.get(1)
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length = self._getASN1Length(p)
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p.getFixBytes(length)
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return ASN1Parser(p.bytes[markIndex:p.index])
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def _getASN1Length(self, p):
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firstLength = p.get(1)
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if firstLength<=127:
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return firstLength
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else:
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lengthLength = firstLength & 0x7F
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return p.get(lengthLength)
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class ARC4(object):
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@classmethod
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def new(cls, userkey):
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self = ARC4()
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self._arc4 = _ARC4.new(userkey)
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return self
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def __init__(self):
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self._arc4 = None
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def decrypt(self, data):
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return self._arc4.decrypt(data)
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class AES(object):
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MODE_CBC = _AES.MODE_CBC
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@classmethod
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def new(cls, userkey, mode, iv):
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self = AES()
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self._aes = _AES.new(userkey, mode, iv)
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return self
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def __init__(self):
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self._aes = None
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def decrypt(self, data):
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return self._aes.decrypt(data)
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class RSA(object):
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def __init__(self, der):
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key = ASN1Parser([ord(x) for x in der])
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key = [key.getChild(x).value for x in range(1, 4)]
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key = [self.bytesToNumber(v) for v in key]
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self._rsa = _RSA.construct(key)
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def bytesToNumber(self, bytes):
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total = 0
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for byte in bytes:
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total = (total << 8) + byte
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return total
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def decrypt(self, data):
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return self._rsa.decrypt(data)
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return (ARC4, RSA, AES)
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def _load_crypto():
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ARC4 = RSA = AES = None
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cryptolist = (_load_crypto_libcrypto, _load_crypto_pycrypto)
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if sys.platform.startswith('win'):
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cryptolist = (_load_crypto_pycrypto, _load_crypto_libcrypto)
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for loader in cryptolist:
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try:
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ARC4, RSA, AES = loader()
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break
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except (ImportError, ADEPTError):
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pass
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return (ARC4, RSA, AES)
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ARC4, RSA, AES = _load_crypto()
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# Do we generate cross reference streams on output?
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# 0 = never
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# 1 = only if present in input
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# 2 = always
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GEN_XREF_STM = 1
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# This is the value for the current document
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gen_xref_stm = False # will be set in PDFSerializer
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# PDF parsing routines from pdfminer, with changes for EBX_HANDLER
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# Utilities
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def choplist(n, seq):
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'''Groups every n elements of the list.'''
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r = []
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for x in seq:
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r.append(x)
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if len(r) == n:
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yield tuple(r)
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r = []
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return
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def nunpack(s, default=0):
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'''Unpacks up to 4 bytes big endian.'''
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l = len(s)
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if not l:
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return default
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elif l == 1:
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return ord(s)
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elif l == 2:
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return struct.unpack('>H', s)[0]
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elif l == 3:
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return struct.unpack('>L', '\x00'+s)[0]
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elif l == 4:
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return struct.unpack('>L', s)[0]
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else:
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return TypeError('invalid length: %d' % l)
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STRICT = 0
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# PS Exceptions
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class PSException(Exception): pass
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class PSEOF(PSException): pass
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class PSSyntaxError(PSException): pass
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class PSTypeError(PSException): pass
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class PSValueError(PSException): pass
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# Basic PostScript Types
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# PSLiteral
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class PSObject(object): pass
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class PSLiteral(PSObject):
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'''
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PS literals (e.g. "/Name").
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Caution: Never create these objects directly.
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Use PSLiteralTable.intern() instead.
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'''
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def __init__(self, name):
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self.name = name.decode('utf-8')
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return
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def __repr__(self):
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name = []
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for char in self.name:
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if not char.isalnum():
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char = '#%02x' % ord(char)
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name.append(char)
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return '/%s' % ''.join(name)
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# PSKeyword
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class PSKeyword(PSObject):
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'''
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PS keywords (e.g. "showpage").
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Caution: Never create these objects directly.
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Use PSKeywordTable.intern() instead.
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'''
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def __init__(self, name):
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self.name = name.decode('utf-8')
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return
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def __repr__(self):
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return self.name
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|
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# PSSymbolTable
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class PSSymbolTable(object):
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'''
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Symbol table that stores PSLiteral or PSKeyword.
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'''
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def __init__(self, classe):
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self.dic = {}
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self.classe = classe
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return
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def intern(self, name):
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if name in self.dic:
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lit = self.dic[name]
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else:
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lit = self.classe(name)
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self.dic[name] = lit
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return lit
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PSLiteralTable = PSSymbolTable(PSLiteral)
|
|
PSKeywordTable = PSSymbolTable(PSKeyword)
|
|
LIT = PSLiteralTable.intern
|
|
KWD = PSKeywordTable.intern
|
|
KEYWORD_BRACE_BEGIN = KWD(b'{')
|
|
KEYWORD_BRACE_END = KWD(b'}')
|
|
KEYWORD_ARRAY_BEGIN = KWD(b'[')
|
|
KEYWORD_ARRAY_END = KWD(b']')
|
|
KEYWORD_DICT_BEGIN = KWD(b'<<')
|
|
KEYWORD_DICT_END = KWD(b'>>')
|
|
|
|
|
|
def literal_name(x):
|
|
if not isinstance(x, PSLiteral):
|
|
if STRICT:
|
|
raise PSTypeError('Literal required: %r' % x)
|
|
else:
|
|
return str(x)
|
|
return x.name
|
|
|
|
def keyword_name(x):
|
|
if not isinstance(x, PSKeyword):
|
|
if STRICT:
|
|
raise PSTypeError('Keyword required: %r' % x)
|
|
else:
|
|
return str(x)
|
|
return x.name
|
|
|
|
|
|
## PSBaseParser
|
|
##
|
|
EOL = re.compile(rb'[\r\n]')
|
|
SPC = re.compile(rb'\s')
|
|
NONSPC = re.compile(rb'\S')
|
|
HEX = re.compile(rb'[0-9a-fA-F]')
|
|
END_LITERAL = re.compile(rb'[#/%\[\]()<>{}\s]')
|
|
END_HEX_STRING = re.compile(rb'[^\s0-9a-fA-F]')
|
|
HEX_PAIR = re.compile(rb'[0-9a-fA-F]{2}|.')
|
|
END_NUMBER = re.compile(rb'[^0-9]')
|
|
END_KEYWORD = re.compile(rb'[#/%\[\]()<>{}\s]')
|
|
END_STRING = re.compile(rb'[()\\]')
|
|
OCT_STRING = re.compile(rb'[0-7]')
|
|
ESC_STRING = { b'b':8, b't':9, b'n':10, b'f':12, b'r':13, b'(':40, b')':41, b'\\':92 }
|
|
|
|
class PSBaseParser(object):
|
|
|
|
'''
|
|
Most basic PostScript parser that performs only basic tokenization.
|
|
'''
|
|
BUFSIZ = 4096
|
|
|
|
def __init__(self, fp):
|
|
self.fp = fp
|
|
self.seek(0)
|
|
return
|
|
|
|
def __repr__(self):
|
|
return '<PSBaseParser: %r, bufpos=%d>' % (self.fp, self.bufpos)
|
|
|
|
def flush(self):
|
|
return
|
|
|
|
def close(self):
|
|
self.flush()
|
|
return
|
|
|
|
def tell(self):
|
|
return self.bufpos+self.charpos
|
|
|
|
def poll(self, pos=None, n=80):
|
|
pos0 = self.fp.tell()
|
|
if not pos:
|
|
pos = self.bufpos+self.charpos
|
|
self.fp.seek(pos)
|
|
self.fp.seek(pos0)
|
|
return
|
|
|
|
def seek(self, pos):
|
|
'''
|
|
Seeks the parser to the given position.
|
|
'''
|
|
self.fp.seek(pos)
|
|
# reset the status for nextline()
|
|
self.bufpos = pos
|
|
self.buf = b''
|
|
self.charpos = 0
|
|
# reset the status for nexttoken()
|
|
self.parse1 = self.parse_main
|
|
self.tokens = []
|
|
return
|
|
|
|
def fillbuf(self):
|
|
if self.charpos < len(self.buf): return
|
|
# fetch next chunk.
|
|
self.bufpos = self.fp.tell()
|
|
self.buf = self.fp.read(self.BUFSIZ)
|
|
if not self.buf:
|
|
raise PSEOF('Unexpected EOF')
|
|
self.charpos = 0
|
|
return
|
|
|
|
def parse_main(self, s, i):
|
|
m = NONSPC.search(s, i)
|
|
if not m:
|
|
return (self.parse_main, len(s))
|
|
j = m.start(0)
|
|
c = bytes([s[j]])
|
|
self.tokenstart = self.bufpos+j
|
|
if c == b'%':
|
|
self.token = c
|
|
return (self.parse_comment, j+1)
|
|
if c == b'/':
|
|
self.token = b''
|
|
return (self.parse_literal, j+1)
|
|
if c in b'-+' or c.isdigit():
|
|
self.token = c
|
|
return (self.parse_number, j+1)
|
|
if c == b'.':
|
|
self.token = c
|
|
return (self.parse_decimal, j+1)
|
|
if c.isalpha():
|
|
self.token = c
|
|
return (self.parse_keyword, j+1)
|
|
if c == b'(':
|
|
self.token = b''
|
|
self.paren = 1
|
|
return (self.parse_string, j+1)
|
|
if c == b'<':
|
|
self.token = b''
|
|
return (self.parse_wopen, j+1)
|
|
if c == b'>':
|
|
self.token = b''
|
|
return (self.parse_wclose, j+1)
|
|
self.add_token(KWD(c))
|
|
return (self.parse_main, j+1)
|
|
|
|
def add_token(self, obj):
|
|
self.tokens.append((self.tokenstart, obj))
|
|
return
|
|
|
|
def parse_comment(self, s, i):
|
|
m = EOL.search(s, i)
|
|
if not m:
|
|
self.token += s[i:]
|
|
return (self.parse_comment, len(s))
|
|
j = m.start(0)
|
|
self.token += s[i:j]
|
|
# We ignore comments.
|
|
#self.tokens.append(self.token)
|
|
return (self.parse_main, j)
|
|
|
|
def parse_literal(self, s, i):
|
|
m = END_LITERAL.search(s, i)
|
|
if not m:
|
|
self.token += s[i:]
|
|
return (self.parse_literal, len(s))
|
|
j = m.start(0)
|
|
self.token += s[i:j]
|
|
c = bytes([s[j]])
|
|
if c == b'#':
|
|
self.hex = b''
|
|
return (self.parse_literal_hex, j+1)
|
|
self.add_token(LIT(self.token))
|
|
return (self.parse_main, j)
|
|
|
|
def parse_literal_hex(self, s, i):
|
|
c = bytes([s[i]])
|
|
if HEX.match(c) and len(self.hex) < 2:
|
|
self.hex += c
|
|
return (self.parse_literal_hex, i+1)
|
|
if self.hex:
|
|
self.token += bytes([int(self.hex, 16)])
|
|
return (self.parse_literal, i)
|
|
|
|
def parse_number(self, s, i):
|
|
m = END_NUMBER.search(s, i)
|
|
if not m:
|
|
self.token += s[i:]
|
|
return (self.parse_number, len(s))
|
|
j = m.start(0)
|
|
self.token += s[i:j]
|
|
c = bytes([s[j]])
|
|
if c == b'.':
|
|
self.token += c
|
|
return (self.parse_decimal, j+1)
|
|
try:
|
|
self.add_token(int(self.token))
|
|
except ValueError:
|
|
pass
|
|
return (self.parse_main, j)
|
|
|
|
def parse_decimal(self, s, i):
|
|
m = END_NUMBER.search(s, i)
|
|
if not m:
|
|
self.token += s[i:]
|
|
return (self.parse_decimal, len(s))
|
|
j = m.start(0)
|
|
self.token += s[i:j]
|
|
self.add_token(Decimal(self.token.decode('utf-8')))
|
|
return (self.parse_main, j)
|
|
|
|
def parse_keyword(self, s, i):
|
|
m = END_KEYWORD.search(s, i)
|
|
if not m:
|
|
self.token += s[i:]
|
|
return (self.parse_keyword, len(s))
|
|
j = m.start(0)
|
|
self.token += s[i:j]
|
|
if self.token == 'true':
|
|
token = True
|
|
elif self.token == 'false':
|
|
token = False
|
|
else:
|
|
token = KWD(self.token)
|
|
self.add_token(token)
|
|
return (self.parse_main, j)
|
|
|
|
def parse_string(self, s, i):
|
|
m = END_STRING.search(s, i)
|
|
if not m:
|
|
self.token += s[i:]
|
|
return (self.parse_string, len(s))
|
|
j = m.start(0)
|
|
self.token += s[i:j]
|
|
c = bytes([s[j]])
|
|
if c == b'\\':
|
|
self.oct = ''
|
|
return (self.parse_string_1, j+1)
|
|
if c == b'(':
|
|
self.paren += 1
|
|
self.token += c
|
|
return (self.parse_string, j+1)
|
|
if c == b')':
|
|
self.paren -= 1
|
|
if self.paren:
|
|
self.token += c
|
|
return (self.parse_string, j+1)
|
|
self.add_token(self.token)
|
|
return (self.parse_main, j+1)
|
|
|
|
def parse_string_1(self, s, i):
|
|
c = bytes([s[i]])
|
|
if OCT_STRING.match(c) and len(self.oct) < 3:
|
|
self.oct += c
|
|
return (self.parse_string_1, i+1)
|
|
if self.oct:
|
|
self.token += bytes([int(self.oct, 8)])
|
|
return (self.parse_string, i)
|
|
if c in ESC_STRING:
|
|
self.token += bytes([ESC_STRING[c]])
|
|
return (self.parse_string, i+1)
|
|
|
|
def parse_wopen(self, s, i):
|
|
c = bytes([s[i]])
|
|
if c.isspace() or HEX.match(c):
|
|
return (self.parse_hexstring, i)
|
|
if c == b'<':
|
|
self.add_token(KEYWORD_DICT_BEGIN)
|
|
i += 1
|
|
return (self.parse_main, i)
|
|
|
|
def parse_wclose(self, s, i):
|
|
c = bytes([s[i]])
|
|
if c == b'>':
|
|
self.add_token(KEYWORD_DICT_END)
|
|
i += 1
|
|
return (self.parse_main, i)
|
|
|
|
def parse_hexstring(self, s, i):
|
|
m1 = END_HEX_STRING.search(s, i)
|
|
if not m1:
|
|
self.token += s[i:]
|
|
return (self.parse_hexstring, len(s))
|
|
j = m1.start(0)
|
|
self.token += s[i:j]
|
|
token = HEX_PAIR.sub(lambda m2: bytes([int(m2.group(0), 16)]),
|
|
SPC.sub(b'', self.token))
|
|
self.add_token(token)
|
|
return (self.parse_main, j)
|
|
|
|
def nexttoken(self):
|
|
while not self.tokens:
|
|
self.fillbuf()
|
|
(self.parse1, self.charpos) = self.parse1(self.buf, self.charpos)
|
|
token = self.tokens.pop(0)
|
|
return token
|
|
|
|
def nextline(self):
|
|
'''
|
|
Fetches a next line that ends either with \\r or \\n.
|
|
'''
|
|
linebuf = b''
|
|
linepos = self.bufpos + self.charpos
|
|
eol = False
|
|
while 1:
|
|
self.fillbuf()
|
|
if eol:
|
|
c = bytes([self.buf[self.charpos]])
|
|
# handle '\r\n'
|
|
if c == b'\n':
|
|
linebuf += c
|
|
self.charpos += 1
|
|
break
|
|
m = EOL.search(self.buf, self.charpos)
|
|
if m:
|
|
linebuf += self.buf[self.charpos:m.end(0)]
|
|
self.charpos = m.end(0)
|
|
if bytes([linebuf[-1]]) == b'\r':
|
|
eol = True
|
|
else:
|
|
break
|
|
else:
|
|
linebuf += self.buf[self.charpos:]
|
|
self.charpos = len(self.buf)
|
|
return (linepos, linebuf)
|
|
|
|
def revreadlines(self):
|
|
'''
|
|
Fetches a next line backword. This is used to locate
|
|
the trailers at the end of a file.
|
|
'''
|
|
self.fp.seek(0, 2)
|
|
pos = self.fp.tell()
|
|
buf = b''
|
|
while 0 < pos:
|
|
prevpos = pos
|
|
pos = max(0, pos-self.BUFSIZ)
|
|
self.fp.seek(pos)
|
|
s = self.fp.read(prevpos-pos)
|
|
if not s: break
|
|
while 1:
|
|
n = max(s.rfind(b'\r'), s.rfind(b'\n'))
|
|
if n == -1:
|
|
buf = s + buf
|
|
break
|
|
yield s[n:]+buf
|
|
s = s[:n]
|
|
buf = b''
|
|
return
|
|
|
|
|
|
## PSStackParser
|
|
##
|
|
class PSStackParser(PSBaseParser):
|
|
|
|
def __init__(self, fp):
|
|
PSBaseParser.__init__(self, fp)
|
|
self.reset()
|
|
return
|
|
|
|
def reset(self):
|
|
self.context = []
|
|
self.curtype = None
|
|
self.curstack = []
|
|
self.results = []
|
|
return
|
|
|
|
def seek(self, pos):
|
|
PSBaseParser.seek(self, pos)
|
|
self.reset()
|
|
return
|
|
|
|
def push(self, *objs):
|
|
self.curstack.extend(objs)
|
|
return
|
|
def pop(self, n):
|
|
objs = self.curstack[-n:]
|
|
self.curstack[-n:] = []
|
|
return objs
|
|
def popall(self):
|
|
objs = self.curstack
|
|
self.curstack = []
|
|
return objs
|
|
def add_results(self, *objs):
|
|
self.results.extend(objs)
|
|
return
|
|
|
|
def start_type(self, pos, type):
|
|
self.context.append((pos, self.curtype, self.curstack))
|
|
(self.curtype, self.curstack) = (type, [])
|
|
return
|
|
def end_type(self, type):
|
|
if self.curtype != type:
|
|
raise PSTypeError('Type mismatch: %r != %r' % (self.curtype, type))
|
|
objs = [ obj for (_,obj) in self.curstack ]
|
|
(pos, self.curtype, self.curstack) = self.context.pop()
|
|
return (pos, objs)
|
|
|
|
def do_keyword(self, pos, token):
|
|
return
|
|
|
|
def nextobject(self, direct=False):
|
|
'''
|
|
Yields a list of objects: keywords, literals, strings (byte arrays),
|
|
numbers, arrays and dictionaries. Arrays and dictionaries
|
|
are represented as Python sequence and dictionaries.
|
|
'''
|
|
while not self.results:
|
|
(pos, token) = self.nexttoken()
|
|
if (isinstance(token, int) or
|
|
isinstance(token, Decimal) or
|
|
isinstance(token, bool) or
|
|
isinstance(token, bytearray) or
|
|
isinstance(token, bytes) or
|
|
isinstance(token, PSLiteral)):
|
|
# normal token
|
|
self.push((pos, token))
|
|
elif token == KEYWORD_ARRAY_BEGIN:
|
|
# begin array
|
|
self.start_type(pos, 'a')
|
|
elif token == KEYWORD_ARRAY_END:
|
|
# end array
|
|
try:
|
|
self.push(self.end_type('a'))
|
|
except PSTypeError:
|
|
if STRICT: raise
|
|
elif token == KEYWORD_DICT_BEGIN:
|
|
# begin dictionary
|
|
self.start_type(pos, 'd')
|
|
elif token == KEYWORD_DICT_END:
|
|
# end dictionary
|
|
try:
|
|
(pos, objs) = self.end_type('d')
|
|
if len(objs) % 2 != 0:
|
|
print("Incomplete dictionary construct")
|
|
objs.append("") # this isn't necessary.
|
|
# temporary fix. is this due to rental books?
|
|
# raise PSSyntaxError(
|
|
# 'Invalid dictionary construct: %r' % objs)
|
|
d = dict((literal_name(k), v) \
|
|
for (k,v) in choplist(2, objs))
|
|
self.push((pos, d))
|
|
except PSTypeError:
|
|
if STRICT: raise
|
|
else:
|
|
self.do_keyword(pos, token)
|
|
if self.context:
|
|
continue
|
|
else:
|
|
if direct:
|
|
return self.pop(1)[0]
|
|
self.flush()
|
|
obj = self.results.pop(0)
|
|
return obj
|
|
|
|
|
|
LITERAL_CRYPT = LIT(b'Crypt')
|
|
LITERALS_FLATE_DECODE = (LIT(b'FlateDecode'), LIT(b'Fl'))
|
|
LITERALS_LZW_DECODE = (LIT(b'LZWDecode'), LIT(b'LZW'))
|
|
LITERALS_ASCII85_DECODE = (LIT(b'ASCII85Decode'), LIT(b'A85'))
|
|
|
|
|
|
## PDF Objects
|
|
##
|
|
class PDFObject(PSObject): pass
|
|
|
|
class PDFException(PSException): pass
|
|
class PDFTypeError(PDFException): pass
|
|
class PDFValueError(PDFException): pass
|
|
class PDFNotImplementedError(PSException): pass
|
|
|
|
|
|
## PDFObjRef
|
|
##
|
|
class PDFObjRef(PDFObject):
|
|
|
|
def __init__(self, doc, objid, genno):
|
|
if objid == 0:
|
|
if STRICT:
|
|
raise PDFValueError('PDF object id cannot be 0.')
|
|
self.doc = doc
|
|
self.objid = objid
|
|
self.genno = genno
|
|
return
|
|
|
|
def __repr__(self):
|
|
return '<PDFObjRef:%d %d>' % (self.objid, self.genno)
|
|
|
|
def resolve(self):
|
|
return self.doc.getobj(self.objid)
|
|
|
|
|
|
# resolve
|
|
def resolve1(x):
|
|
'''
|
|
Resolve an object. If this is an array or dictionary,
|
|
it may still contains some indirect objects inside.
|
|
'''
|
|
while isinstance(x, PDFObjRef):
|
|
x = x.resolve()
|
|
return x
|
|
|
|
def resolve_all(x):
|
|
'''
|
|
Recursively resolve X and all the internals.
|
|
Make sure there is no indirect reference within the nested object.
|
|
This procedure might be slow.
|
|
'''
|
|
while isinstance(x, PDFObjRef):
|
|
x = x.resolve()
|
|
if isinstance(x, list):
|
|
x = [ resolve_all(v) for v in x ]
|
|
elif isinstance(x, dict):
|
|
for (k,v) in iter(x.items()):
|
|
x[k] = resolve_all(v)
|
|
return x
|
|
|
|
def decipher_all(decipher, objid, genno, x):
|
|
'''
|
|
Recursively decipher X.
|
|
'''
|
|
if isinstance(x, bytearray) or isinstance(x,bytes):
|
|
return decipher(objid, genno, x)
|
|
decf = lambda v: decipher_all(decipher, objid, genno, v)
|
|
if isinstance(x, list):
|
|
x = [decf(v) for v in x]
|
|
elif isinstance(x, dict):
|
|
x = dict((k, decf(v)) for (k, v) in iter(x.items()))
|
|
return x
|
|
|
|
|
|
# Type cheking
|
|
def int_value(x):
|
|
x = resolve1(x)
|
|
if not isinstance(x, int):
|
|
if STRICT:
|
|
raise PDFTypeError('Integer required: %r' % x)
|
|
return 0
|
|
return x
|
|
|
|
def decimal_value(x):
|
|
x = resolve1(x)
|
|
if not isinstance(x, Decimal):
|
|
if STRICT:
|
|
raise PDFTypeError('Decimal required: %r' % x)
|
|
return 0.0
|
|
return x
|
|
|
|
def num_value(x):
|
|
x = resolve1(x)
|
|
if not (isinstance(x, int) or isinstance(x, Decimal)):
|
|
if STRICT:
|
|
raise PDFTypeError('Int or Float required: %r' % x)
|
|
return 0
|
|
return x
|
|
|
|
def str_value(x):
|
|
x = resolve1(x)
|
|
if not (isinstance(x, bytearray) or isinstance(x, bytes)):
|
|
if STRICT:
|
|
raise PDFTypeError('String required: %r' % x)
|
|
return ''
|
|
return x
|
|
|
|
def list_value(x):
|
|
x = resolve1(x)
|
|
if not (isinstance(x, list) or isinstance(x, tuple)):
|
|
if STRICT:
|
|
raise PDFTypeError('List required: %r' % x)
|
|
return []
|
|
return x
|
|
|
|
def dict_value(x):
|
|
x = resolve1(x)
|
|
if not isinstance(x, dict):
|
|
if STRICT:
|
|
raise PDFTypeError('Dict required: %r' % x)
|
|
return {}
|
|
return x
|
|
|
|
def stream_value(x):
|
|
x = resolve1(x)
|
|
if not isinstance(x, PDFStream):
|
|
if STRICT:
|
|
raise PDFTypeError('PDFStream required: %r' % x)
|
|
return PDFStream({}, '')
|
|
return x
|
|
|
|
# ascii85decode(data)
|
|
def ascii85decode(data):
|
|
n = b = 0
|
|
out = b''
|
|
for c in data:
|
|
if b'!' <= c and c <= b'u':
|
|
n += 1
|
|
b = b*85+(c-33)
|
|
if n == 5:
|
|
out += struct.pack('>L',b)
|
|
n = b = 0
|
|
elif c == b'z':
|
|
assert n == 0
|
|
out += b'\0\0\0\0'
|
|
elif c == b'~':
|
|
if n:
|
|
for _ in range(5-n):
|
|
b = b*85+84
|
|
out += struct.pack('>L',b)[:n-1]
|
|
break
|
|
return out
|
|
|
|
|
|
## PDFStream type
|
|
class PDFStream(PDFObject):
|
|
def __init__(self, dic, rawdata, decipher=None):
|
|
length = int_value(dic.get('Length', 0))
|
|
eol = rawdata[length:]
|
|
# quick and dirty fix for false length attribute,
|
|
# might not work if the pdf stream parser has a problem
|
|
if decipher != None and decipher.__name__ == 'decrypt_aes':
|
|
if (len(rawdata) % 16) != 0:
|
|
cutdiv = len(rawdata) // 16
|
|
rawdata = rawdata[:16*cutdiv]
|
|
else:
|
|
if eol in (b'\r', b'\n', b'\r\n'):
|
|
rawdata = rawdata[:length]
|
|
|
|
self.dic = dic
|
|
self.rawdata = rawdata
|
|
self.decipher = decipher
|
|
self.data = None
|
|
self.decdata = None
|
|
self.objid = None
|
|
self.genno = None
|
|
return
|
|
|
|
def set_objid(self, objid, genno):
|
|
self.objid = objid
|
|
self.genno = genno
|
|
return
|
|
|
|
def __repr__(self):
|
|
if self.rawdata:
|
|
return '<PDFStream(%r): raw=%d, %r>' % \
|
|
(self.objid, len(self.rawdata), self.dic)
|
|
else:
|
|
return '<PDFStream(%r): data=%d, %r>' % \
|
|
(self.objid, len(self.data), self.dic)
|
|
|
|
def decode(self):
|
|
assert self.data is None and self.rawdata is not None
|
|
data = self.rawdata
|
|
if self.decipher:
|
|
# Handle encryption
|
|
data = self.decipher(self.objid, self.genno, data)
|
|
if gen_xref_stm:
|
|
self.decdata = data # keep decrypted data
|
|
if 'Filter' not in self.dic:
|
|
self.data = data
|
|
self.rawdata = None
|
|
return
|
|
filters = self.dic['Filter']
|
|
if not isinstance(filters, list):
|
|
filters = [ filters ]
|
|
for f in filters:
|
|
if f in LITERALS_FLATE_DECODE:
|
|
# will get errors if the document is encrypted.
|
|
data = zlib.decompress(data)
|
|
elif f in LITERALS_LZW_DECODE:
|
|
data = b''.join(LZWDecoder(BytesIO(data)).run())
|
|
elif f in LITERALS_ASCII85_DECODE:
|
|
data = ascii85decode(data)
|
|
elif f == LITERAL_CRYPT:
|
|
raise PDFNotImplementedError('/Crypt filter is unsupported')
|
|
else:
|
|
raise PDFNotImplementedError('Unsupported filter: %r' % f)
|
|
# apply predictors
|
|
if 'DP' in self.dic:
|
|
params = self.dic['DP']
|
|
else:
|
|
params = self.dic.get('DecodeParms', {})
|
|
if 'Predictor' in params:
|
|
pred = int_value(params['Predictor'])
|
|
if pred:
|
|
if pred != 12:
|
|
raise PDFNotImplementedError(
|
|
'Unsupported predictor: %r' % pred)
|
|
if 'Columns' not in params:
|
|
raise PDFValueError(
|
|
'Columns undefined for predictor=12')
|
|
columns = int_value(params['Columns'])
|
|
buf = b''
|
|
ent0 = b'\x00' * columns
|
|
for i in range(0, len(data), columns+1):
|
|
pred = data[i]
|
|
ent1 = data[i+1:i+1+columns]
|
|
if pred == b'\x02':
|
|
ent1 = b''.join(bytes([(a+b) & 255]) \
|
|
for (a,b) in zip(ent0,ent1))
|
|
buf += ent1
|
|
ent0 = ent1
|
|
data = buf
|
|
self.data = data
|
|
self.rawdata = None
|
|
return
|
|
|
|
def get_data(self):
|
|
if self.data is None:
|
|
self.decode()
|
|
return self.data
|
|
|
|
def get_rawdata(self):
|
|
return self.rawdata
|
|
|
|
def get_decdata(self):
|
|
if self.decdata is not None:
|
|
return self.decdata
|
|
data = self.rawdata
|
|
if self.decipher and data:
|
|
# Handle encryption
|
|
data = self.decipher(self.objid, self.genno, data)
|
|
return data
|
|
|
|
|
|
## PDF Exceptions
|
|
##
|
|
class PDFSyntaxError(PDFException): pass
|
|
class PDFNoValidXRef(PDFSyntaxError): pass
|
|
class PDFEncryptionError(PDFException): pass
|
|
class PDFPasswordIncorrect(PDFEncryptionError): pass
|
|
|
|
# some predefined literals and keywords.
|
|
LITERAL_OBJSTM = LIT(b'ObjStm')
|
|
LITERAL_XREF = LIT(b'XRef')
|
|
LITERAL_PAGE = LIT(b'Page')
|
|
LITERAL_PAGES = LIT(b'Pages')
|
|
LITERAL_CATALOG = LIT(b'Catalog')
|
|
|
|
|
|
## XRefs
|
|
##
|
|
|
|
## PDFXRef
|
|
##
|
|
class PDFXRef(object):
|
|
|
|
def __init__(self):
|
|
self.offsets = None
|
|
return
|
|
|
|
def __repr__(self):
|
|
return '<PDFXRef: objs=%d>' % len(self.offsets)
|
|
|
|
def objids(self):
|
|
return iter(self.offsets.keys())
|
|
|
|
def load(self, parser):
|
|
self.offsets = {}
|
|
while 1:
|
|
try:
|
|
(pos, line) = parser.nextline()
|
|
except PSEOF:
|
|
raise PDFNoValidXRef('Unexpected EOF - file corrupted?')
|
|
if not line:
|
|
raise PDFNoValidXRef('Premature eof: %r' % parser)
|
|
if line.startswith(b'trailer'):
|
|
parser.seek(pos)
|
|
break
|
|
f = line.strip().split(b' ')
|
|
if len(f) != 2:
|
|
raise PDFNoValidXRef('Trailer not found: %r: line=%r' % (parser, line))
|
|
try:
|
|
(start, nobjs) = map(int, f)
|
|
except ValueError:
|
|
raise PDFNoValidXRef('Invalid line: %r: line=%r' % (parser, line))
|
|
for objid in range(start, start+nobjs):
|
|
try:
|
|
(_, line) = parser.nextline()
|
|
except PSEOF:
|
|
raise PDFNoValidXRef('Unexpected EOF - file corrupted?')
|
|
f = line.strip().split(b' ')
|
|
if len(f) != 3:
|
|
raise PDFNoValidXRef('Invalid XRef format: %r, line=%r' % (parser, line))
|
|
(pos, genno, use) = f
|
|
if use != b'n':
|
|
continue
|
|
self.offsets[objid] = (int(genno.decode('utf-8')), int(pos.decode('utf-8')))
|
|
self.load_trailer(parser)
|
|
return
|
|
|
|
KEYWORD_TRAILER = KWD(b'trailer')
|
|
def load_trailer(self, parser):
|
|
try:
|
|
(_,kwd) = parser.nexttoken()
|
|
assert kwd is self.KEYWORD_TRAILER
|
|
(_,dic) = parser.nextobject(direct=True)
|
|
except PSEOF:
|
|
x = parser.pop(1)
|
|
if not x:
|
|
raise PDFNoValidXRef('Unexpected EOF - file corrupted')
|
|
(_,dic) = x[0]
|
|
self.trailer = dict_value(dic)
|
|
return
|
|
|
|
def getpos(self, objid):
|
|
try:
|
|
(genno, pos) = self.offsets[objid]
|
|
except KeyError:
|
|
raise
|
|
return (None, pos)
|
|
|
|
|
|
## PDFXRefStream
|
|
##
|
|
class PDFXRefStream(object):
|
|
|
|
def __init__(self):
|
|
self.index = None
|
|
self.data = None
|
|
self.entlen = None
|
|
self.fl1 = self.fl2 = self.fl3 = None
|
|
return
|
|
|
|
def __repr__(self):
|
|
return '<PDFXRef: objids=%s>' % self.index
|
|
|
|
def objids(self):
|
|
for first, size in self.index:
|
|
for objid in range(first, first + size):
|
|
yield objid
|
|
|
|
def load(self, parser, debug=0):
|
|
(_,objid) = parser.nexttoken() # ignored
|
|
(_,genno) = parser.nexttoken() # ignored
|
|
(_,kwd) = parser.nexttoken()
|
|
(_,stream) = parser.nextobject()
|
|
if not isinstance(stream, PDFStream) or \
|
|
stream.dic['Type'] is not LITERAL_XREF:
|
|
raise PDFNoValidXRef('Invalid PDF stream spec.')
|
|
size = stream.dic['Size']
|
|
index = stream.dic.get('Index', (0,size))
|
|
self.index = zip(itertools.islice(index, 0, None, 2),
|
|
itertools.islice(index, 1, None, 2))
|
|
(self.fl1, self.fl2, self.fl3) = stream.dic['W']
|
|
self.data = stream.get_data()
|
|
self.entlen = self.fl1+self.fl2+self.fl3
|
|
self.trailer = stream.dic
|
|
return
|
|
|
|
def getpos(self, objid):
|
|
offset = 0
|
|
for first, size in self.index:
|
|
if first <= objid and objid < (first + size):
|
|
break
|
|
offset += size
|
|
else:
|
|
raise KeyError(objid)
|
|
i = self.entlen * ((objid - first) + offset)
|
|
ent = self.data[i:i+self.entlen]
|
|
f1 = nunpack(ent[:self.fl1], 1)
|
|
if f1 == 1:
|
|
pos = nunpack(ent[self.fl1:self.fl1+self.fl2])
|
|
genno = nunpack(ent[self.fl1+self.fl2:])
|
|
return (None, pos)
|
|
elif f1 == 2:
|
|
objid = nunpack(ent[self.fl1:self.fl1+self.fl2])
|
|
index = nunpack(ent[self.fl1+self.fl2:])
|
|
return (objid, index)
|
|
# this is a free object
|
|
raise KeyError(objid)
|
|
|
|
|
|
## PDFDocument
|
|
##
|
|
## A PDFDocument object represents a PDF document.
|
|
## Since a PDF file is usually pretty big, normally it is not loaded
|
|
## at once. Rather it is parsed dynamically as processing goes.
|
|
## A PDF parser is associated with the document.
|
|
##
|
|
class PDFDocument(object):
|
|
|
|
def __init__(self):
|
|
self.xrefs = []
|
|
self.objs = {}
|
|
self.parsed_objs = {}
|
|
self.root = None
|
|
self.catalog = None
|
|
self.parser = None
|
|
self.encryption = None
|
|
self.decipher = None
|
|
return
|
|
|
|
# set_parser(parser)
|
|
# Associates the document with an (already initialized) parser object.
|
|
def set_parser(self, parser):
|
|
if self.parser:
|
|
return
|
|
self.parser = parser
|
|
# The document is set to be temporarily ready during collecting
|
|
# all the basic information about the document, e.g.
|
|
# the header, the encryption information, and the access rights
|
|
# for the document.
|
|
self.ready = True
|
|
# Retrieve the information of each header that was appended
|
|
# (maybe multiple times) at the end of the document.
|
|
self.xrefs = parser.read_xref()
|
|
for xref in self.xrefs:
|
|
trailer = xref.trailer
|
|
if not trailer: continue
|
|
|
|
# If there's an encryption info, remember it.
|
|
if 'Encrypt' in trailer:
|
|
#assert not self.encryption
|
|
try:
|
|
self.encryption = (list_value(trailer['ID']),
|
|
dict_value(trailer['Encrypt']))
|
|
# fix for bad files
|
|
except:
|
|
self.encryption = (b'ffffffffffffffffffffffffffffffffffff',
|
|
dict_value(trailer['Encrypt']))
|
|
if 'Root' in trailer:
|
|
self.set_root(dict_value(trailer['Root']))
|
|
break
|
|
else:
|
|
raise PDFSyntaxError('No /Root object! - Is this really a PDF?')
|
|
# The document is set to be non-ready again, until all the
|
|
# proper initialization (asking the password key and
|
|
# verifying the access permission, so on) is finished.
|
|
self.ready = False
|
|
return
|
|
|
|
# set_root(root)
|
|
# Set the Root dictionary of the document.
|
|
# Each PDF file must have exactly one /Root dictionary.
|
|
def set_root(self, root):
|
|
self.root = root
|
|
self.catalog = dict_value(self.root)
|
|
if self.catalog.get('Type') is not LITERAL_CATALOG:
|
|
if STRICT:
|
|
raise PDFSyntaxError('Catalog not found!')
|
|
return
|
|
# initialize(password='')
|
|
# Perform the initialization with a given password.
|
|
# This step is mandatory even if there's no password associated
|
|
# with the document.
|
|
def initialize(self, password=b''):
|
|
if not self.encryption:
|
|
self.is_printable = self.is_modifiable = self.is_extractable = True
|
|
self.ready = True
|
|
raise PDFEncryptionError('Document is not encrypted.')
|
|
return
|
|
(docid, param) = self.encryption
|
|
type = literal_name(param['Filter'])
|
|
if type == 'Adobe.APS':
|
|
return self.initialize_adobe_ps(password, docid, param)
|
|
if type == 'Standard':
|
|
return self.initialize_standard(password, docid, param)
|
|
if type == 'EBX_HANDLER':
|
|
return self.initialize_ebx(password, docid, param)
|
|
raise PDFEncryptionError('Unknown filter: param=%r' % param)
|
|
|
|
def initialize_adobe_ps(self, password, docid, param):
|
|
global KEYFILEPATH
|
|
self.decrypt_key = self.genkey_adobe_ps(param)
|
|
self.genkey = self.genkey_v4
|
|
self.decipher = self.decrypt_aes
|
|
self.ready = True
|
|
return
|
|
|
|
def genkey_adobe_ps(self, param):
|
|
# nice little offline principal keys dictionary
|
|
# global static principal key for German Onleihe / Bibliothek Digital
|
|
principalkeys = { b'bibliothek-digital.de': codecs.decode(b'rRwGv2tbpKov1krvv7PO0ws9S436/lArPlfipz5Pqhw=','base64')}
|
|
self.is_printable = self.is_modifiable = self.is_extractable = True
|
|
length = int_value(param.get('Length', 0)) / 8
|
|
edcdata = str_value(param.get('EDCData')).decode('base64')
|
|
pdrllic = str_value(param.get('PDRLLic')).decode('base64')
|
|
pdrlpol = str_value(param.get('PDRLPol')).decode('base64')
|
|
edclist = []
|
|
for pair in edcdata.split(b'\n'):
|
|
edclist.append(pair)
|
|
# principal key request
|
|
for key in principalkeys:
|
|
if key in pdrllic:
|
|
principalkey = principalkeys[key]
|
|
else:
|
|
raise ADEPTError('Cannot find principal key for this pdf')
|
|
shakey = SHA256(principalkey)
|
|
ivector = bytes(16) # 16 zero bytes
|
|
plaintext = AES.new(shakey,AES.MODE_CBC,ivector).decrypt(edclist[9].decode('base64'))
|
|
if plaintext[-16:] != bytearray(b'\0x10')*16:
|
|
raise ADEPTError('Offlinekey cannot be decrypted, aborting ...')
|
|
pdrlpol = AES.new(plaintext[16:32],AES.MODE_CBC,edclist[2].decode('base64')).decrypt(pdrlpol)
|
|
if pdrlpol[-1] < 1 or pdrlpol[-1] > 16:
|
|
raise ADEPTError('Could not decrypt PDRLPol, aborting ...')
|
|
else:
|
|
cutter = -1 * pdrlpol[-1]
|
|
pdrlpol = pdrlpol[:cutter]
|
|
return plaintext[:16]
|
|
|
|
PASSWORD_PADDING = b'(\xbfN^Nu\x8aAd\x00NV\xff\xfa\x01\x08..' \
|
|
b'\x00\xb6\xd0h>\x80/\x0c\xa9\xfedSiz'
|
|
# experimental aes pw support
|
|
def initialize_standard(self, password, docid, param):
|
|
# copy from a global variable
|
|
V = int_value(param.get('V', 0))
|
|
if (V <=0 or V > 4):
|
|
raise PDFEncryptionError('Unknown algorithm: param=%r' % param)
|
|
length = int_value(param.get('Length', 40)) # Key length (bits)
|
|
O = str_value(param['O'])
|
|
R = int_value(param['R']) # Revision
|
|
if 5 <= R:
|
|
raise PDFEncryptionError('Unknown revision: %r' % R)
|
|
U = str_value(param['U'])
|
|
P = int_value(param['P'])
|
|
try:
|
|
EncMetadata = str_value(param['EncryptMetadata'])
|
|
except:
|
|
EncMetadata = b'True'
|
|
self.is_printable = bool(P & 4)
|
|
self.is_modifiable = bool(P & 8)
|
|
self.is_extractable = bool(P & 16)
|
|
self.is_annotationable = bool(P & 32)
|
|
self.is_formsenabled = bool(P & 256)
|
|
self.is_textextractable = bool(P & 512)
|
|
self.is_assemblable = bool(P & 1024)
|
|
self.is_formprintable = bool(P & 2048)
|
|
# Algorithm 3.2
|
|
password = (password+self.PASSWORD_PADDING)[:32] # 1
|
|
hash = hashlib.md5(password) # 2
|
|
hash.update(O) # 3
|
|
hash.update(struct.pack('<l', P)) # 4
|
|
hash.update(docid[0]) # 5
|
|
# aes special handling if metadata isn't encrypted
|
|
if EncMetadata == ('False' or 'false'):
|
|
hash.update(codecs.decode(b'ffffffff','hex'))
|
|
if 5 <= R:
|
|
# 8
|
|
for _ in range(50):
|
|
hash = hashlib.md5(hash.digest()[:length/8])
|
|
key = hash.digest()[:length/8]
|
|
if R == 2:
|
|
# Algorithm 3.4
|
|
u1 = ARC4.new(key).decrypt(password)
|
|
elif R >= 3:
|
|
# Algorithm 3.5
|
|
hash = hashlib.md5(self.PASSWORD_PADDING) # 2
|
|
hash.update(docid[0]) # 3
|
|
x = ARC4.new(key).decrypt(hash.digest()[:16]) # 4
|
|
for i in range(1,19+1):
|
|
k = b''.join(bytes([c ^ i]) for c in key )
|
|
x = ARC4.new(k).decrypt(x)
|
|
u1 = x+x # 32bytes total
|
|
if R == 2:
|
|
is_authenticated = (u1 == U)
|
|
else:
|
|
is_authenticated = (u1[:16] == U[:16])
|
|
if not is_authenticated:
|
|
raise ADEPTError('Password is not correct.')
|
|
self.decrypt_key = key
|
|
# genkey method
|
|
if V == 1 or V == 2:
|
|
self.genkey = self.genkey_v2
|
|
elif V == 3:
|
|
self.genkey = self.genkey_v3
|
|
elif V == 4:
|
|
self.genkey = self.genkey_v2
|
|
#self.genkey = self.genkey_v3 if V == 3 else self.genkey_v2
|
|
# rc4
|
|
if V != 4:
|
|
self.decipher = self.decipher_rc4 # XXX may be AES
|
|
# aes
|
|
elif V == 4 and length == 128:
|
|
self.decipher = self.decipher_aes
|
|
elif V == 4 and length == 256:
|
|
raise PDFNotImplementedError('AES256 encryption is currently unsupported')
|
|
self.ready = True
|
|
return
|
|
|
|
def initialize_ebx(self, password, docid, param):
|
|
self.is_printable = self.is_modifiable = self.is_extractable = True
|
|
rsa = RSA(password)
|
|
length = int_value(param.get('Length', 0)) / 8
|
|
rights = codecs.decode(param.get('ADEPT_LICENSE'), 'base64')
|
|
rights = zlib.decompress(rights, -15)
|
|
rights = etree.fromstring(rights)
|
|
expr = './/{http://ns.adobe.com/adept}encryptedKey'
|
|
bookkey = codecs.decode(''.join(rights.findtext(expr)).encode('utf-8'),'base64')
|
|
bookkey = rsa.decrypt(bookkey)
|
|
if bookkey[0] != 2:
|
|
raise ADEPTError('error decrypting book session key')
|
|
index = bookkey.index(b'\0') + 1
|
|
bookkey = bookkey[index:]
|
|
ebx_V = int_value(param.get('V', 4))
|
|
ebx_type = int_value(param.get('EBX_ENCRYPTIONTYPE', 6))
|
|
# added because of improper booktype / decryption book session key errors
|
|
if length > 0:
|
|
if len(bookkey) == length:
|
|
if ebx_V == 3:
|
|
V = 3
|
|
else:
|
|
V = 2
|
|
elif len(bookkey) == length + 1:
|
|
V = bookkey[0]
|
|
bookkey = bookkey[1:]
|
|
else:
|
|
print("ebx_V is %d and ebx_type is %d" % (ebx_V, ebx_type))
|
|
print("length is %d and len(bookkey) is %d" % (length, len(bookkey)))
|
|
print("bookkey[0] is %d" % bookkey[0])
|
|
raise ADEPTError('error decrypting book session key - mismatched length')
|
|
else:
|
|
# proper length unknown try with whatever you have
|
|
print("ebx_V is %d and ebx_type is %d" % (ebx_V, ebx_type))
|
|
print("length is %d and len(bookkey) is %d" % (length, len(bookkey)))
|
|
print("bookkey[0] is %d" % bookkey[0])
|
|
if ebx_V == 3:
|
|
V = 3
|
|
else:
|
|
V = 2
|
|
self.decrypt_key = bookkey
|
|
self.genkey = self.genkey_v3 if V == 3 else self.genkey_v2
|
|
self.decipher = self.decrypt_rc4
|
|
self.ready = True
|
|
return
|
|
|
|
# genkey functions
|
|
def genkey_v2(self, objid, genno):
|
|
objid = struct.pack('<L', objid)[:3]
|
|
genno = struct.pack('<L', genno)[:2]
|
|
key = self.decrypt_key + objid + genno
|
|
hash = hashlib.md5(key)
|
|
key = hash.digest()[:min(len(self.decrypt_key) + 5, 16)]
|
|
return key
|
|
|
|
def genkey_v3(self, objid, genno):
|
|
objid = struct.pack('<L', objid ^ 0x3569ac)
|
|
genno = struct.pack('<L', genno ^ 0xca96)
|
|
key = self.decrypt_key
|
|
key += objid[0] + genno[0] + objid[1] + genno[1] + objid[2] + b'sAlT'
|
|
hash = hashlib.md5(key)
|
|
key = hash.digest()[:min(len(self.decrypt_key) + 5, 16)]
|
|
return key
|
|
|
|
# aes v2 and v4 algorithm
|
|
def genkey_v4(self, objid, genno):
|
|
objid = struct.pack('<L', objid)[:3]
|
|
genno = struct.pack('<L', genno)[:2]
|
|
key = self.decrypt_key + objid + genno + b'sAlT'
|
|
hash = hashlib.md5(key)
|
|
key = hash.digest()[:min(len(self.decrypt_key) + 5, 16)]
|
|
return key
|
|
|
|
def decrypt_aes(self, objid, genno, data):
|
|
key = self.genkey(objid, genno)
|
|
ivector = data[:16]
|
|
data = data[16:]
|
|
plaintext = AES.new(key,AES.MODE_CBC,ivector).decrypt(data)
|
|
# remove pkcs#5 aes padding
|
|
cutter = -1 * plaintext[-1]
|
|
plaintext = plaintext[:cutter]
|
|
return plaintext
|
|
|
|
def decrypt_aes256(self, objid, genno, data):
|
|
key = self.genkey(objid, genno)
|
|
ivector = data[:16]
|
|
data = data[16:]
|
|
plaintext = AES.new(key,AES.MODE_CBC,ivector).decrypt(data)
|
|
# remove pkcs#5 aes padding
|
|
cutter = -1 * plaintext[-1]
|
|
plaintext = plaintext[:cutter]
|
|
return plaintext
|
|
|
|
def decrypt_rc4(self, objid, genno, data):
|
|
key = self.genkey(objid, genno)
|
|
return ARC4.new(key).decrypt(data)
|
|
|
|
|
|
KEYWORD_OBJ = KWD(b'obj')
|
|
|
|
def getobj(self, objid):
|
|
if not self.ready:
|
|
raise PDFException('PDFDocument not initialized')
|
|
#assert self.xrefs
|
|
if objid in self.objs:
|
|
genno = 0
|
|
obj = self.objs[objid]
|
|
else:
|
|
for xref in self.xrefs:
|
|
try:
|
|
(stmid, index) = xref.getpos(objid)
|
|
break
|
|
except KeyError:
|
|
pass
|
|
else:
|
|
#if STRICT:
|
|
# raise PDFSyntaxError('Cannot locate objid=%r' % objid)
|
|
return None
|
|
if stmid:
|
|
if gen_xref_stm:
|
|
return PDFObjStmRef(objid, stmid, index)
|
|
# Stuff from pdfminer: extract objects from object stream
|
|
stream = stream_value(self.getobj(stmid))
|
|
if stream.dic.get('Type') is not LITERAL_OBJSTM:
|
|
if STRICT:
|
|
raise PDFSyntaxError('Not a stream object: %r' % stream)
|
|
try:
|
|
n = stream.dic['N']
|
|
except KeyError:
|
|
if STRICT:
|
|
raise PDFSyntaxError('N is not defined: %r' % stream)
|
|
n = 0
|
|
|
|
if stmid in self.parsed_objs:
|
|
objs = self.parsed_objs[stmid]
|
|
else:
|
|
parser = PDFObjStrmParser(stream.get_data(), self)
|
|
objs = []
|
|
try:
|
|
while 1:
|
|
(_,obj) = parser.nextobject()
|
|
objs.append(obj)
|
|
except PSEOF:
|
|
pass
|
|
self.parsed_objs[stmid] = objs
|
|
genno = 0
|
|
i = n*2+index
|
|
try:
|
|
obj = objs[i]
|
|
except IndexError:
|
|
raise PDFSyntaxError('Invalid object number: objid=%r' % (objid))
|
|
if isinstance(obj, PDFStream):
|
|
obj.set_objid(objid, 0)
|
|
else:
|
|
self.parser.seek(index)
|
|
(_,objid1) = self.parser.nexttoken() # objid
|
|
(_,genno) = self.parser.nexttoken() # genno
|
|
#assert objid1 == objid, (objid, objid1)
|
|
(_,kwd) = self.parser.nexttoken()
|
|
# #### hack around malformed pdf files
|
|
# assert objid1 == objid, (objid, objid1)
|
|
## if objid1 != objid:
|
|
## x = []
|
|
## while kwd is not self.KEYWORD_OBJ:
|
|
## (_,kwd) = self.parser.nexttoken()
|
|
## x.append(kwd)
|
|
## if x:
|
|
## objid1 = x[-2]
|
|
## genno = x[-1]
|
|
##
|
|
if kwd is not self.KEYWORD_OBJ:
|
|
raise PDFSyntaxError(
|
|
'Invalid object spec: offset=%r' % index)
|
|
(_,obj) = self.parser.nextobject()
|
|
if isinstance(obj, PDFStream):
|
|
obj.set_objid(objid, genno)
|
|
if self.decipher:
|
|
obj = decipher_all(self.decipher, objid, genno, obj)
|
|
self.objs[objid] = obj
|
|
return obj
|
|
|
|
|
|
class PDFObjStmRef(object):
|
|
maxindex = 0
|
|
def __init__(self, objid, stmid, index):
|
|
self.objid = objid
|
|
self.stmid = stmid
|
|
self.index = index
|
|
if index > PDFObjStmRef.maxindex:
|
|
PDFObjStmRef.maxindex = index
|
|
|
|
|
|
## PDFParser
|
|
##
|
|
class PDFParser(PSStackParser):
|
|
|
|
def __init__(self, doc, fp):
|
|
PSStackParser.__init__(self, fp)
|
|
self.doc = doc
|
|
self.doc.set_parser(self)
|
|
return
|
|
|
|
def __repr__(self):
|
|
return '<PDFParser>'
|
|
|
|
KEYWORD_R = KWD(b'R')
|
|
KEYWORD_ENDOBJ = KWD(b'endobj')
|
|
KEYWORD_STREAM = KWD(b'stream')
|
|
KEYWORD_XREF = KWD(b'xref')
|
|
KEYWORD_STARTXREF = KWD(b'startxref')
|
|
def do_keyword(self, pos, token):
|
|
if token in (self.KEYWORD_XREF, self.KEYWORD_STARTXREF):
|
|
self.add_results(*self.pop(1))
|
|
return
|
|
if token is self.KEYWORD_ENDOBJ:
|
|
self.add_results(*self.pop(4))
|
|
return
|
|
|
|
if token is self.KEYWORD_R:
|
|
# reference to indirect object
|
|
try:
|
|
((_,objid), (_,genno)) = self.pop(2)
|
|
(objid, genno) = (int(objid), int(genno))
|
|
obj = PDFObjRef(self.doc, objid, genno)
|
|
self.push((pos, obj))
|
|
except PSSyntaxError:
|
|
pass
|
|
return
|
|
|
|
if token is self.KEYWORD_STREAM:
|
|
# stream object
|
|
((_,dic),) = self.pop(1)
|
|
dic = dict_value(dic)
|
|
try:
|
|
objlen = int_value(dic['Length'])
|
|
except KeyError:
|
|
if STRICT:
|
|
raise PDFSyntaxError('/Length is undefined: %r' % dic)
|
|
objlen = 0
|
|
self.seek(pos)
|
|
try:
|
|
(_, line) = self.nextline() # 'stream'
|
|
except PSEOF:
|
|
if STRICT:
|
|
raise PDFSyntaxError('Unexpected EOF')
|
|
return
|
|
pos += len(line)
|
|
self.fp.seek(pos)
|
|
data = self.fp.read(objlen)
|
|
self.seek(pos+objlen)
|
|
while 1:
|
|
try:
|
|
(linepos, line) = self.nextline()
|
|
except PSEOF:
|
|
if STRICT:
|
|
raise PDFSyntaxError('Unexpected EOF')
|
|
break
|
|
if b'endstream' in line:
|
|
i = line.index(b'endstream')
|
|
objlen += i
|
|
data += line[:i]
|
|
break
|
|
objlen += len(line)
|
|
data += line
|
|
self.seek(pos+objlen)
|
|
obj = PDFStream(dic, data, self.doc.decipher)
|
|
self.push((pos, obj))
|
|
return
|
|
|
|
# others
|
|
self.push((pos, token))
|
|
return
|
|
|
|
def find_xref(self):
|
|
# search the last xref table by scanning the file backwards.
|
|
prev = None
|
|
for line in self.revreadlines():
|
|
line = line.strip()
|
|
if line == b'startxref': break
|
|
if line:
|
|
prev = line
|
|
else:
|
|
raise PDFNoValidXRef('Unexpected EOF')
|
|
return int(prev)
|
|
|
|
# read xref table
|
|
def read_xref_from(self, start, xrefs):
|
|
self.seek(start)
|
|
self.reset()
|
|
try:
|
|
(pos, token) = self.nexttoken()
|
|
except PSEOF:
|
|
raise PDFNoValidXRef('Unexpected EOF')
|
|
if isinstance(token, int):
|
|
# XRefStream: PDF-1.5
|
|
if GEN_XREF_STM == 1:
|
|
global gen_xref_stm
|
|
gen_xref_stm = True
|
|
self.seek(pos)
|
|
self.reset()
|
|
xref = PDFXRefStream()
|
|
xref.load(self)
|
|
else:
|
|
if token is not self.KEYWORD_XREF:
|
|
raise PDFNoValidXRef('xref not found: pos=%d, token=%r' %
|
|
(pos, token))
|
|
self.nextline()
|
|
xref = PDFXRef()
|
|
xref.load(self)
|
|
xrefs.append(xref)
|
|
trailer = xref.trailer
|
|
if 'XRefStm' in trailer:
|
|
pos = int_value(trailer['XRefStm'])
|
|
self.read_xref_from(pos, xrefs)
|
|
if 'Prev' in trailer:
|
|
# find previous xref
|
|
pos = int_value(trailer['Prev'])
|
|
self.read_xref_from(pos, xrefs)
|
|
return
|
|
|
|
# read xref tables and trailers
|
|
def read_xref(self):
|
|
xrefs = []
|
|
trailerpos = None
|
|
try:
|
|
pos = self.find_xref()
|
|
self.read_xref_from(pos, xrefs)
|
|
except PDFNoValidXRef:
|
|
# fallback
|
|
self.seek(0)
|
|
pat = re.compile(rb'^(\d+)\s+(\d+)\s+obj\b')
|
|
offsets = {}
|
|
xref = PDFXRef()
|
|
while 1:
|
|
try:
|
|
(pos, line) = self.nextline()
|
|
except PSEOF:
|
|
break
|
|
if line.startswith(b'trailer'):
|
|
trailerpos = pos # remember last trailer
|
|
m = pat.match(line)
|
|
if not m: continue
|
|
(objid, genno) = m.groups()
|
|
offsets[int(objid)] = (0, pos)
|
|
if not offsets: raise
|
|
xref.offsets = offsets
|
|
if trailerpos:
|
|
self.seek(trailerpos)
|
|
xref.load_trailer(self)
|
|
xrefs.append(xref)
|
|
return xrefs
|
|
|
|
## PDFObjStrmParser
|
|
##
|
|
class PDFObjStrmParser(PDFParser):
|
|
|
|
def __init__(self, data, doc):
|
|
PSStackParser.__init__(self, BytesIO(data))
|
|
self.doc = doc
|
|
return
|
|
|
|
def flush(self):
|
|
self.add_results(*self.popall())
|
|
return
|
|
|
|
KEYWORD_R = KWD(b'R')
|
|
def do_keyword(self, pos, token):
|
|
if token is self.KEYWORD_R:
|
|
# reference to indirect object
|
|
try:
|
|
((_,objid), (_,genno)) = self.pop(2)
|
|
(objid, genno) = (int(objid), int(genno))
|
|
obj = PDFObjRef(self.doc, objid, genno)
|
|
self.push((pos, obj))
|
|
except PSSyntaxError:
|
|
pass
|
|
return
|
|
# others
|
|
self.push((pos, token))
|
|
return
|
|
|
|
###
|
|
### My own code, for which there is none else to blame
|
|
|
|
class PDFSerializer(object):
|
|
def __init__(self, inf, userkey):
|
|
global GEN_XREF_STM, gen_xref_stm
|
|
gen_xref_stm = GEN_XREF_STM > 1
|
|
self.version = inf.read(8)
|
|
inf.seek(0)
|
|
self.doc = doc = PDFDocument()
|
|
parser = PDFParser(doc, inf)
|
|
doc.initialize(userkey)
|
|
self.objids = objids = set()
|
|
for xref in reversed(doc.xrefs):
|
|
trailer = xref.trailer
|
|
for objid in xref.objids():
|
|
objids.add(objid)
|
|
trailer = dict(trailer)
|
|
trailer.pop('Prev', None)
|
|
trailer.pop('XRefStm', None)
|
|
if 'Encrypt' in trailer:
|
|
objids.remove(trailer.pop('Encrypt').objid)
|
|
self.trailer = trailer
|
|
|
|
def dump(self, outf):
|
|
self.outf = outf
|
|
self.write(self.version)
|
|
self.write(b'\n%\xe2\xe3\xcf\xd3\n')
|
|
doc = self.doc
|
|
objids = self.objids
|
|
xrefs = {}
|
|
maxobj = max(objids)
|
|
trailer = dict(self.trailer)
|
|
trailer['Size'] = maxobj + 1
|
|
for objid in objids:
|
|
obj = doc.getobj(objid)
|
|
if isinstance(obj, PDFObjStmRef):
|
|
xrefs[objid] = obj
|
|
continue
|
|
if obj is not None:
|
|
try:
|
|
genno = obj.genno
|
|
except AttributeError:
|
|
genno = 0
|
|
xrefs[objid] = (self.tell(), genno)
|
|
self.serialize_indirect(objid, obj)
|
|
startxref = self.tell()
|
|
|
|
if not gen_xref_stm:
|
|
self.write(b'xref\n')
|
|
self.write(b'0 %d\n' % (maxobj + 1,))
|
|
for objid in range(0, maxobj + 1):
|
|
if objid in xrefs:
|
|
# force the genno to be 0
|
|
self.write(b"%010d 00000 n \n" % xrefs[objid][0])
|
|
else:
|
|
self.write(b"%010d %05d f \n" % (0, 65535))
|
|
|
|
self.write(b'trailer\n')
|
|
self.serialize_object(trailer)
|
|
self.write(b'\nstartxref\n%d\n%%%%EOF' % startxref)
|
|
|
|
else: # Generate crossref stream.
|
|
|
|
# Calculate size of entries
|
|
maxoffset = max(startxref, maxobj)
|
|
maxindex = PDFObjStmRef.maxindex
|
|
fl2 = 2
|
|
power = 65536
|
|
while maxoffset >= power:
|
|
fl2 += 1
|
|
power *= 256
|
|
fl3 = 1
|
|
power = 256
|
|
while maxindex >= power:
|
|
fl3 += 1
|
|
power *= 256
|
|
|
|
index = []
|
|
first = None
|
|
prev = None
|
|
data = []
|
|
# Put the xrefstream's reference in itself
|
|
startxref = self.tell()
|
|
maxobj += 1
|
|
xrefs[maxobj] = (startxref, 0)
|
|
for objid in sorted(xrefs):
|
|
if first is None:
|
|
first = objid
|
|
elif objid != prev + 1:
|
|
index.extend((first, prev - first + 1))
|
|
first = objid
|
|
prev = objid
|
|
objref = xrefs[objid]
|
|
if isinstance(objref, PDFObjStmRef):
|
|
f1 = 2
|
|
f2 = objref.stmid
|
|
f3 = objref.index
|
|
else:
|
|
f1 = 1
|
|
f2 = objref[0]
|
|
# we force all generation numbers to be 0
|
|
# f3 = objref[1]
|
|
f3 = 0
|
|
|
|
data.append(struct.pack('>B', f1))
|
|
data.append(struct.pack('>L', f2)[-fl2:])
|
|
data.append(struct.pack('>L', f3)[-fl3:])
|
|
index.extend((first, prev - first + 1))
|
|
data = zlib.compress(b''.join(data))
|
|
dic = {'Type': LITERAL_XREF, 'Size': prev + 1, 'Index': index,
|
|
'W': [1, fl2, fl3], 'Length': len(data),
|
|
'Filter': LITERALS_FLATE_DECODE[0],
|
|
'Root': trailer['Root'],}
|
|
if 'Info' in trailer:
|
|
dic['Info'] = trailer['Info']
|
|
xrefstm = PDFStream(dic, data)
|
|
self.serialize_indirect(maxobj, xrefstm)
|
|
self.write(b'startxref\n%d\n%%%%EOF' % startxref)
|
|
def write(self, data):
|
|
self.outf.write(data)
|
|
self.last = data[-1:]
|
|
|
|
def tell(self):
|
|
return self.outf.tell()
|
|
|
|
def escape_string(self, string):
|
|
string = string.replace(b'\\', b'\\\\')
|
|
string = string.replace(b'\n', rb'\n')
|
|
string = string.replace(b'(', rb'\(')
|
|
string = string.replace(b')', rb'\)')
|
|
return string
|
|
|
|
def serialize_object(self, obj):
|
|
if isinstance(obj, dict):
|
|
# Correct malformed Mac OS resource forks for Stanza
|
|
if 'ResFork' in obj and 'Type' in obj and 'Subtype' not in obj \
|
|
and isinstance(obj['Type'], int):
|
|
obj['Subtype'] = obj['Type']
|
|
del obj['Type']
|
|
# end - hope this doesn't have bad effects
|
|
self.write(b'<<')
|
|
for key, val in obj.items():
|
|
self.write(str(LIT(key.encode('utf-8'))).encode('utf-8'))
|
|
self.serialize_object(val)
|
|
self.write(b'>>')
|
|
elif isinstance(obj, list):
|
|
self.write(b'[')
|
|
for val in obj:
|
|
self.serialize_object(val)
|
|
self.write(b']')
|
|
elif isinstance(obj, bytearray):
|
|
self.write(b'(%s)' % self.escape_string(obj))
|
|
elif isinstance(obj, bytes):
|
|
self.write(b'(%s)' % self.escape_string(obj))
|
|
elif isinstance(obj, str):
|
|
self.write(b'(%s)' % self.escape_string(obj.encode('utf-8')))
|
|
elif isinstance(obj, bool):
|
|
if self.last.isalnum():
|
|
self.write(b' ')
|
|
self.write(str(obj).lower().encode('utf-8'))
|
|
elif isinstance(obj, int):
|
|
if self.last.isalnum():
|
|
self.write(b' ')
|
|
self.write(str(obj).encode('utf-8'))
|
|
elif isinstance(obj, Decimal):
|
|
if self.last.isalnum():
|
|
self.write(b' ')
|
|
self.write(str(obj).encode('utf-8'))
|
|
elif isinstance(obj, PDFObjRef):
|
|
if self.last.isalnum():
|
|
self.write(b' ')
|
|
self.write(b'%d %d R' % (obj.objid, 0))
|
|
elif isinstance(obj, PDFStream):
|
|
### If we don't generate cross ref streams the object streams
|
|
### are no longer useful, as we have extracted all objects from
|
|
### them. Therefore leave them out from the output.
|
|
if obj.dic.get('Type') == LITERAL_OBJSTM and not gen_xref_stm:
|
|
self.write('(deleted)')
|
|
else:
|
|
data = obj.get_decdata()
|
|
self.serialize_object(obj.dic)
|
|
self.write(b'stream\n')
|
|
self.write(data)
|
|
self.write(b'\nendstream')
|
|
else:
|
|
data = str(obj).encode('utf-8')
|
|
if bytes([data[0]]).isalnum() and self.last.isalnum():
|
|
self.write(b' ')
|
|
self.write(data)
|
|
|
|
def serialize_indirect(self, objid, obj):
|
|
self.write(b'%d 0 obj' % (objid,))
|
|
self.serialize_object(obj)
|
|
if self.last.isalnum():
|
|
self.write(b'\n')
|
|
self.write(b'endobj\n')
|
|
|
|
|
|
|
|
|
|
def decryptBook(userkey, inpath, outpath):
|
|
if RSA is None:
|
|
raise ADEPTError("PyCryptodome or OpenSSL must be installed.")
|
|
with open(inpath, 'rb') as inf:
|
|
serializer = PDFSerializer(inf, userkey)
|
|
with open(outpath, 'wb') as outf:
|
|
# help construct to make sure the method runs to the end
|
|
try:
|
|
serializer.dump(outf)
|
|
except Exception as e:
|
|
print("error writing pdf: {0}".format(e))
|
|
return 2
|
|
return 0
|
|
|
|
|
|
def cli_main():
|
|
sys.stdout=SafeUnbuffered(sys.stdout)
|
|
sys.stderr=SafeUnbuffered(sys.stderr)
|
|
argv=unicode_argv()
|
|
progname = os.path.basename(argv[0])
|
|
if len(argv) != 4:
|
|
print("usage: {0} <keyfile.der> <inbook.pdf> <outbook.pdf>".format(progname))
|
|
return 1
|
|
keypath, inpath, outpath = argv[1:]
|
|
userkey = open(keypath,'rb').read()
|
|
result = decryptBook(userkey, inpath, outpath)
|
|
if result == 0:
|
|
print("Successfully decrypted {0:s} as {1:s}".format(os.path.basename(inpath),os.path.basename(outpath)))
|
|
return result
|
|
|
|
|
|
def gui_main():
|
|
try:
|
|
import tkinter
|
|
import tkinter.constants
|
|
import tkinter.filedialog
|
|
import tkinter.messagebox
|
|
import traceback
|
|
except:
|
|
return cli_main()
|
|
|
|
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=tkinter.constants.X, expand=1)
|
|
body = tkinter.Frame(self)
|
|
body.pack(fill=tkinter.constants.X, expand=1)
|
|
sticky = tkinter.constants.E + tkinter.constants.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("adeptkey.der"):
|
|
self.keypath.insert(0, "adeptkey.der")
|
|
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=tkinter.constants.LEFT)
|
|
tkinter.Frame(buttons, width=10).pack(side=tkinter.constants.LEFT)
|
|
button = tkinter.Button(
|
|
buttons, text="Quit", width=10, command=self.quit)
|
|
button.pack(side=tkinter.constants.RIGHT)
|
|
|
|
def get_keypath(self):
|
|
keypath = tkinter.filedialog.askopenfilename(
|
|
parent=None, title="Select Adobe Adept \'.der\' key file",
|
|
defaultextension=".der",
|
|
filetypes=[('Adobe Adept DER-encoded files', '.der'),
|
|
('All Files', '.*')])
|
|
if keypath:
|
|
keypath = os.path.normpath(keypath)
|
|
self.keypath.delete(0, tkinter.constants.END)
|
|
self.keypath.insert(0, keypath)
|
|
return
|
|
|
|
def get_inpath(self):
|
|
inpath = tkinter.filedialog.askopenfilename(
|
|
parent=None, title="Select ADEPT-encrypted PDF file to decrypt",
|
|
defaultextension=".pdf", filetypes=[('PDF files', '.pdf')])
|
|
if inpath:
|
|
inpath = os.path.normpath(inpath)
|
|
self.inpath.delete(0, tkinter.constants.END)
|
|
self.inpath.insert(0, inpath)
|
|
return
|
|
|
|
def get_outpath(self):
|
|
outpath = tkinter.filedialog.asksaveasfilename(
|
|
parent=None, title="Select unencrypted PDF file to produce",
|
|
defaultextension=".pdf", filetypes=[('PDF files', '.pdf')])
|
|
if outpath:
|
|
outpath = os.path.normpath(outpath)
|
|
self.outpath.delete(0, tkinter.constants.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
|
|
userkey = open(keypath,'rb').read()
|
|
self.status['text'] = "Decrypting..."
|
|
try:
|
|
decrypt_status = decryptBook(userkey, inpath, outpath)
|
|
except Exception as e:
|
|
self.status['text'] = "Error; {0}".format(e.args[0])
|
|
return
|
|
if decrypt_status == 0:
|
|
self.status['text'] = "File successfully decrypted"
|
|
else:
|
|
self.status['text'] = "The was an error decrypting the file."
|
|
|
|
|
|
root = tkinter.Tk()
|
|
if RSA is None:
|
|
root.withdraw()
|
|
tkinter.messagebox.showerror(
|
|
"INEPT PDF",
|
|
"This script requires OpenSSL or PyCrypto, which must be installed "
|
|
"separately. Read the top-of-script comment for details.")
|
|
return 1
|
|
root.title("Adobe Adept PDF Decrypter v.{0}".format(__version__))
|
|
root.resizable(True, False)
|
|
root.minsize(370, 0)
|
|
DecryptionDialog(root).pack(fill=tkinter.constants.X, expand=1)
|
|
root.mainloop()
|
|
return 0
|
|
|
|
|
|
if __name__ == '__main__':
|
|
if len(sys.argv) > 1:
|
|
sys.exit(cli_main())
|
|
sys.exit(gui_main())
|