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pdf-parser.py
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pdf-parser.py
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#!/usr/bin/env python
__description__ = 'pdf-parser, use it to parse a PDF document'
__author__ = 'Didier Stevens'
__version__ = '0.7.10'
__date__ = '2024/10/26'
__minimum_python_version__ = (2, 5, 1)
__maximum_python_version__ = (3, 11, 1)
"""
Source code put in public domain by Didier Stevens, no Copyright
https://DidierStevens.com
Use at your own risk
History:
2008/05/02: continue
2008/05/03: continue
2008/06/02: streams
2008/10/19: refactor, grep & extract functionality
2008/10/20: reference
2008/10/21: cleanup
2008/11/12: V0.3 dictionary parser
2008/11/13: option elements
2008/11/14: continue
2009/05/05: added /ASCIIHexDecode support (thanks Justin Prosco)
2009/05/11: V0.3.1 updated usage, added --verbose and --extract
2009/07/16: V0.3.2 Added Canonicalize (thanks Justin Prosco)
2009/07/18: bugfix EqualCanonical
2009/07/24: V0.3.3 Added --hash option
2009/07/25: EqualCanonical for option --type, added option --nocanonicalizedoutput
2009/07/28: V0.3.4 Added ASCII85Decode support
2009/08/01: V0.3.5 Updated ASCIIHexDecode to support whitespace obfuscation
2009/08/30: V0.3.6 TestPythonVersion
2010/01/08: V0.3.7 Added RLE and LZW support (thanks pARODY); added dump option
2010/01/09: Fixed parsing of incomplete startxref
2010/09/22: V0.3.8 Changed dump option, updated PrettyPrint, added debug option
2011/12/17: fixed bugs empty objects
2012/03/11: V0.3.9 fixed bugs double nested [] in PrettyPrintSub (thanks kurt)
2013/01/11: V0.3.10 Extract and dump bug fixes by Priit; added content option
2013/02/16: Performance improvement in cPDFTokenizer by using StringIO for token building by Christophe Vandeplas; xrange replaced with range
2013/02/16: V0.4.0 added http/https support; added error handling for missing file or URL; ; added support for ZIP file with password 'infected'
2013/03/13: V0.4.1 fixes for Python 3
2013/04/11: V0.4.2 modified PrettyPrintSub for strings with unprintable characters
2013/05/04: Added options searchstream, unfiltered, casesensitive, regex
2013/09/18: V0.4.3 fixed regression bug -w option
2014/09/25: V0.5.0 added option -g
2014/09/29: Added PrintGenerateObject and PrintOutputObject
2014/12/05: V0.6.0 Added YARA support
2014/12/09: cleanup, refactoring
2014/12/13: Python 3 fixes
2015/01/11: Added support for multiple YARA rule files; added request to search in trailer
2015/01/31: V0.6.1 Added optionyarastrings
2015/02/09: Added decoders
2015/04/05: V0.6.2 Added generateembedded
2015/04/06: fixed bug reported by Kurt for stream produced by Ghostscript where endstream is not preceded by whitespace; fixed prettyprint bug
2015/04/24: V0.6.3 when option dump's filename is -, content is dumped to stdout
2015/08/12: V0.6.4 option hash now also calculates hashes of streams when selecting or searching objects; and displays hexasciidump first line
2016/07/27: V0.6.5 bugfix whitespace 0x00 0x0C after stream 0x0D 0x0A reported by @mr_me
2016/11/20: V0.6.6 added workaround zlib errors FlateDecode
2016/12/17: V0.6.7 added option -k
2017/01/07: V0.6.8 changed cPDFParseDictionary to handle strings () with % character
2017/10/28: fixed bug
2017/10/29: added # support for option -y
2018/06/29: V0.6.9 added option --overridingfilters
2018/10/20: added keywords to statistics
2019/02/22: V0.7.0 added option -O --objstm to parse the stream of /ObjStm objects, inspired by a contributor wishing anonymity
2019/03/01: V0.7.1 added ContainsName for correct keyword statistics (-a)
2019/04/12: V0.7.2 Python 2.6.6 compatibility fix
2019/07/30: bug fixes (including fixes Josef Hinteregger)
2019/09/26: V0.7.3 added multiple id selection to option -o; added man page (-m); added environment variable PDFPARSER_OPTIONS; bug fixes
2019/11/05: V0.7.4 fixed plugin path when compiled with pyinstaller, replaced eval with int
2021/07/03: V0.7.5 bug fixes; fixed ASCII85Decode Python 3 bug thanks to R Primus
2021/11/23: V0.7.6 Python 3 bug fixes
2022/05/24: bug fixes
2022/11/09: V0.7.7 added support for environment variable DSS_DEFAULT_HASH_ALGORITHMS
2023/01/03: V0.7.8 added unreferenced objects to statistics
2024/03/21: V0.7.9 added option jsonoutput; added verbose YARA rules
2024/10/25: V0.7.10 /ObjStm fix (x9090 PR)
2024/10/26: added pyzipper support
Todo:
- handle printf todo
- support for JS hex string EC61C64349DB8D88AF0523C4C06E0F4D.pdf.vir
"""
import re
import optparse
import zlib
import binascii
import hashlib
import sys
import time
import os
import textwrap
import json
if sys.version_info[0] >= 3:
from io import StringIO
import urllib.request
urllib23 = urllib.request
import configparser as ConfigParser
else:
from cStringIO import StringIO
import urllib2
urllib23 = urllib2
import ConfigParser
try:
import yara
except:
pass
try:
import pyzipper as zipfile
except ImportError:
import zipfile
CHAR_WHITESPACE = 1
CHAR_DELIMITER = 2
CHAR_REGULAR = 3
CONTEXT_NONE = 1
CONTEXT_OBJ = 2
CONTEXT_XREF = 3
CONTEXT_TRAILER = 4
PDF_ELEMENT_COMMENT = 1
PDF_ELEMENT_INDIRECT_OBJECT = 2
PDF_ELEMENT_XREF = 3
PDF_ELEMENT_TRAILER = 4
PDF_ELEMENT_STARTXREF = 5
PDF_ELEMENT_MALFORMED = 6
dumplinelength = 16
def PrintManual():
manual = '''
Manual:
This manual is a work in progress.
There is a free PDF analysis book:
https://blog.didierstevens.com/2010/09/26/free-malicious-pdf-analysis-e-book/
Option -o is used to select objects by id. Provide a single id or multiple ids separated by a comma (,).
When environment variable PDFPARSER_OPTIONS is defined, the options it defines are added implicitely to the command line arguments.
Use this to define options you want included with each use of pdf-parser.py.
Like option -O, to parse stream objects (/ObjStm).
By defining PDFPARSER_OPTIONS=-O, pdf-parser will always parse stream objects (when found).
PS: this feature is experimental.
Option -H calculates the MD5 hash by default.
This can be changed by setting environment variable DSS_DEFAULT_HASH_ALGORITHMS.
Like this: set DSS_DEFAULT_HASH_ALGORITHMS=sha256
Option --jsonoutput produces JSON output with the stream content of all objects with streams. Options -f and --overridingfilters apply.
For example, if option -f is used, the JSON output contains the filtered streams, otherwise the JSON output contains the unfiltered streams.
'''
for line in manual.split('\n'):
print(textwrap.fill(line))
#Convert 2 Bytes If Python 3
def C2BIP3(string):
if sys.version_info[0] > 2:
if type(string) == bytes:
return string
else:
return bytes([ord(x) for x in string])
else:
return string
#Convert 2 String If Python 3
def C2SIP3(bytes):
if sys.version_info[0] > 2:
return ''.join([chr(byte) for byte in bytes])
else:
return bytes
# CIC: Call If Callable
def CIC(expression):
if callable(expression):
return expression()
else:
return expression
# IFF: IF Function
def IFF(expression, valueTrue, valueFalse):
if expression:
return CIC(valueTrue)
else:
return CIC(valueFalse)
def Timestamp(epoch=None):
if epoch == None:
localTime = time.localtime()
else:
localTime = time.localtime(epoch)
return '%04d%02d%02d-%02d%02d%02d' % localTime[0:6]
def CopyWithoutWhiteSpace(content):
result = []
for token in content:
if token[0] != CHAR_WHITESPACE:
result.append(token)
return result
def Obj2Str(content):
return ''.join(map(lambda x: repr(x[1])[1:-1], CopyWithoutWhiteSpace(content)))
def CreateZipFileObject(arg1, arg2):
if 'AESZipFile' in dir(zipfile):
return zipfile.AESZipFile(arg1, arg2)
else:
return zipfile.ZipFile(arg1, arg2)
class cPDFDocument:
def __init__(self, file):
self.file = file
if type(file) != str:
self.infile = file
elif file.lower().startswith('http://') or file.lower().startswith('https://'):
try:
if sys.hexversion >= 0x020601F0:
self.infile = urllib23.urlopen(file, timeout=5)
else:
self.infile = urllib23.urlopen(file)
except urllib23.HTTPError:
print('Error accessing URL %s' % file)
print(sys.exc_info()[1])
sys.exit()
elif file.lower().endswith('.zip'):
try:
self.zipfile = CreateZipFileObject(file, 'r')
self.infile = self.zipfile.open(self.zipfile.infolist()[0], 'r', C2BIP3('infected'))
except:
print('Error opening file %s' % file)
print(sys.exc_info()[1])
sys.exit()
else:
try:
self.infile = open(file, 'rb')
except:
print('Error opening file %s' % file)
print(sys.exc_info()[1])
sys.exit()
self.ungetted = []
self.position = -1
def byte(self):
if len(self.ungetted) != 0:
self.position += 1
return self.ungetted.pop()
inbyte = self.infile.read(1)
if not inbyte or inbyte == '':
self.infile.close()
return None
self.position += 1
return ord(inbyte)
def unget(self, byte):
self.position -= 1
self.ungetted.append(byte)
def CharacterClass(byte):
if byte == 0 or byte == 9 or byte == 10 or byte == 12 or byte == 13 or byte == 32:
return CHAR_WHITESPACE
if byte == 0x28 or byte == 0x29 or byte == 0x3C or byte == 0x3E or byte == 0x5B or byte == 0x5D or byte == 0x7B or byte == 0x7D or byte == 0x2F or byte == 0x25:
return CHAR_DELIMITER
return CHAR_REGULAR
def IsNumeric(str):
return re.match('^[0-9]+', str)
class cPDFTokenizer:
def __init__(self, file):
self.oPDF = cPDFDocument(file)
self.ungetted = []
def Token(self):
if len(self.ungetted) != 0:
return self.ungetted.pop()
if self.oPDF == None:
return None
self.byte = self.oPDF.byte()
if self.byte == None:
self.oPDF = None
return None
elif CharacterClass(self.byte) == CHAR_WHITESPACE:
file_str = StringIO()
while self.byte != None and CharacterClass(self.byte) == CHAR_WHITESPACE:
file_str.write(chr(self.byte))
self.byte = self.oPDF.byte()
if self.byte != None:
self.oPDF.unget(self.byte)
else:
self.oPDF = None
self.token = file_str.getvalue()
return (CHAR_WHITESPACE, self.token)
elif CharacterClass(self.byte) == CHAR_REGULAR:
file_str = StringIO()
while self.byte != None and CharacterClass(self.byte) == CHAR_REGULAR:
file_str.write(chr(self.byte))
self.byte = self.oPDF.byte()
if self.byte != None:
self.oPDF.unget(self.byte)
else:
self.oPDF = None
self.token = file_str.getvalue()
return (CHAR_REGULAR, self.token)
else:
if self.byte == 0x3C:
self.byte = self.oPDF.byte()
if self.byte == 0x3C:
return (CHAR_DELIMITER, '<<')
else:
self.oPDF.unget(self.byte)
return (CHAR_DELIMITER, '<')
elif self.byte == 0x3E:
self.byte = self.oPDF.byte()
if self.byte == 0x3E:
return (CHAR_DELIMITER, '>>')
else:
self.oPDF.unget(self.byte)
return (CHAR_DELIMITER, '>')
elif self.byte == 0x25:
file_str = StringIO()
while self.byte != None:
file_str.write(chr(self.byte))
if self.byte == 10 or self.byte == 13:
self.byte = self.oPDF.byte()
break
self.byte = self.oPDF.byte()
if self.byte != None:
if self.byte == 10:
file_str.write(chr(self.byte))
else:
self.oPDF.unget(self.byte)
else:
self.oPDF = None
self.token = file_str.getvalue()
return (CHAR_DELIMITER, self.token)
return (CHAR_DELIMITER, chr(self.byte))
def TokenIgnoreWhiteSpace(self):
token = self.Token()
while token != None and token[0] == CHAR_WHITESPACE:
token = self.Token()
return token
def Tokens(self):
tokens = []
token = self.Token()
while token != None:
tokens.append(token)
token = self.Token()
return tokens
def unget(self, byte):
self.ungetted.append(byte)
class cPDFParser:
def __init__(self, file, verbose=False, extract=None, objstm=None):
self.context = CONTEXT_NONE
self.content = []
self.oPDFTokenizer = cPDFTokenizer(file)
self.verbose = verbose
self.extract = extract
self.objstm = objstm
def GetObject(self):
while True:
if self.context == CONTEXT_OBJ:
self.token = self.oPDFTokenizer.Token()
else:
self.token = self.oPDFTokenizer.TokenIgnoreWhiteSpace()
if self.token:
if self.token[0] == CHAR_DELIMITER:
if self.token[1][0] == '%':
if self.context == CONTEXT_OBJ:
self.content.append(self.token)
else:
return cPDFElementComment(self.token[1])
elif self.token[1] == '/':
self.token2 = self.oPDFTokenizer.Token()
if self.token2[0] == CHAR_REGULAR:
if self.context != CONTEXT_NONE:
self.content.append((CHAR_DELIMITER, self.token[1] + self.token2[1]))
elif self.verbose:
print('todo 1: %s' % (self.token[1] + self.token2[1]))
else:
self.oPDFTokenizer.unget(self.token2)
if self.context != CONTEXT_NONE:
self.content.append(self.token)
elif self.verbose:
print('todo 2: %d %s' % (self.token[0], repr(self.token[1])))
elif self.context != CONTEXT_NONE:
self.content.append(self.token)
elif self.verbose:
print('todo 3: %d %s' % (self.token[0], repr(self.token[1])))
elif self.token[0] == CHAR_WHITESPACE:
if self.context != CONTEXT_NONE:
self.content.append(self.token)
elif self.verbose:
print('todo 4: %d %s' % (self.token[0], repr(self.token[1])))
else:
if self.context == CONTEXT_OBJ:
if self.token[1] == 'endobj':
self.oPDFElementIndirectObject = cPDFElementIndirectObject(self.objectId, self.objectVersion, self.content, self.objstm)
self.context = CONTEXT_NONE
self.content = []
return self.oPDFElementIndirectObject
else:
self.content.append(self.token)
elif self.context == CONTEXT_TRAILER:
if self.token[1] == 'startxref' or self.token[1] == 'xref':
self.oPDFElementTrailer = cPDFElementTrailer(self.content)
self.oPDFTokenizer.unget(self.token)
self.context = CONTEXT_NONE
self.content = []
return self.oPDFElementTrailer
else:
self.content.append(self.token)
elif self.context == CONTEXT_XREF:
if self.token[1] == 'trailer' or self.token[1] == 'xref':
self.oPDFElementXref = cPDFElementXref(self.content)
self.oPDFTokenizer.unget(self.token)
self.context = CONTEXT_NONE
self.content = []
return self.oPDFElementXref
else:
self.content.append(self.token)
else:
if IsNumeric(self.token[1]):
self.token2 = self.oPDFTokenizer.TokenIgnoreWhiteSpace()
if IsNumeric(self.token2[1]):
self.token3 = self.oPDFTokenizer.TokenIgnoreWhiteSpace()
if self.token3[1] == 'obj':
self.objectId = int(self.token[1], 10)
self.objectVersion = int(self.token2[1], 10)
self.context = CONTEXT_OBJ
else:
self.oPDFTokenizer.unget(self.token3)
self.oPDFTokenizer.unget(self.token2)
if self.verbose:
print('todo 6: %d %s' % (self.token[0], repr(self.token[1])))
else:
self.oPDFTokenizer.unget(self.token2)
if self.verbose:
print('todo 7: %d %s' % (self.token[0], repr(self.token[1])))
elif self.token[1] == 'trailer':
self.context = CONTEXT_TRAILER
self.content = [self.token]
elif self.token[1] == 'xref':
self.context = CONTEXT_XREF
self.content = [self.token]
elif self.token[1] == 'startxref':
self.token2 = self.oPDFTokenizer.TokenIgnoreWhiteSpace()
if self.token2 and IsNumeric(self.token2[1]):
return cPDFElementStartxref(int(self.token2[1], 10))
else:
self.oPDFTokenizer.unget(self.token2)
if self.verbose:
print('todo 9: %d %s' % (self.token[0], repr(self.token[1])))
elif self.extract:
self.bytes = ''
while self.token:
self.bytes += self.token[1]
self.token = self.oPDFTokenizer.Token()
return cPDFElementMalformed(self.bytes)
elif self.verbose:
print('todo 10: %d %s' % (self.token[0], repr(self.token[1])))
else:
break
class cPDFElementComment:
def __init__(self, comment):
self.type = PDF_ELEMENT_COMMENT
self.comment = comment
# if re.match('^%PDF-[0-9]\.[0-9]', self.token[1]):
# print(repr(self.token[1]))
# elif re.match('^%%EOF', self.token[1]):
# print(repr(self.token[1]))
class cPDFElementXref:
def __init__(self, content):
self.type = PDF_ELEMENT_XREF
self.content = content
class cPDFElementTrailer:
def __init__(self, content):
self.type = PDF_ELEMENT_TRAILER
self.content = content
def Contains(self, keyword):
data = ''
for i in range(0, len(self.content)):
if self.content[i][1] == 'stream':
break
else:
data += Canonicalize(self.content[i][1])
return data.upper().find(keyword.upper()) != -1
def IIf(expr, truepart, falsepart):
if expr:
return truepart
else:
return falsepart
class cPDFElementIndirectObject:
def __init__(self, id, version, content, objstm=None):
self.type = PDF_ELEMENT_INDIRECT_OBJECT
self.id = id
self.version = version
self.content = content
self.objstm = objstm
#fix stream for Ghostscript bug reported by Kurt
if self.ContainsStream():
position = len(self.content) - 1
if position < 0:
return
while self.content[position][0] == CHAR_WHITESPACE and position >= 0:
position -= 1
if position < 0:
return
if self.content[position][1].endswith('endstream\n'):
self.content = self.content[0:position] + [(self.content[position][0], self.content[position][1][:-len('endstream\n')])] + [(CHAR_REGULAR, 'endstream')] + self.content[position+1:]
return
if self.content[position][0] != CHAR_REGULAR:
return
if self.content[position][1] == 'endstream':
return
if not self.content[position][1].endswith('endstream'):
return
self.content = self.content[0:position] + [(self.content[position][0], self.content[position][1][:-len('endstream')])] + [(self.content[position][0], 'endstream')] + self.content[position+1:]
def GetType(self):
content = CopyWithoutWhiteSpace(self.content)
dictionary = 0
for i in range(0, len(content)):
if content[i][0] == CHAR_DELIMITER and content[i][1] == '<<':
dictionary += 1
if content[i][0] == CHAR_DELIMITER and content[i][1] == '>>':
dictionary -= 1
if dictionary == 1 and content[i][0] == CHAR_DELIMITER and EqualCanonical(content[i][1], '/Type') and i < len(content) - 1:
return content[i+1][1]
return ''
def GetReferences(self):
content = CopyWithoutWhiteSpace(self.content)
references = []
for i in range(0, len(content)):
if i > 1 and content[i][0] == CHAR_REGULAR and content[i][1] == 'R' and content[i-2][0] == CHAR_REGULAR and IsNumeric(content[i-2][1]) and content[i-1][0] == CHAR_REGULAR and IsNumeric(content[i-1][1]):
references.append((content[i-2][1], content[i-1][1], content[i][1]))
return references
def References(self, index):
for ref in self.GetReferences():
if ref[0] == index:
return True
return False
def ContainsStream(self):
for i in range(0, len(self.content)):
if self.content[i][0] == CHAR_REGULAR and self.content[i][1] == 'stream':
return self.content[0:i]
return False
def Contains(self, keyword):
data = ''
for i in range(0, len(self.content)):
if self.content[i][1] == 'stream':
break
else:
data += Canonicalize(self.content[i][1])
return data.upper().find(keyword.upper()) != -1
def ContainsName(self, keyword):
for token in self.content:
if token[1] == 'stream':
return False
if token[0] == CHAR_DELIMITER and EqualCanonical(token[1], keyword):
return True
return False
def StreamContains(self, keyword, filter, casesensitive, regex, overridingfilters):
if not self.ContainsStream():
return False
streamData = self.Stream(filter, overridingfilters)
if filter and streamData == 'No filters':
streamData = self.Stream(False, overridingfilters)
if isinstance(streamData, bytes):
keyword = keyword.encode()
if regex:
return re.search(keyword, streamData, IIf(casesensitive, 0, re.I))
elif casesensitive:
return keyword in streamData
else:
return keyword.lower() in streamData.lower()
def Stream(self, filter=True, overridingfilters=''):
state = 'start'
countDirectories = 0
data = ''
filters = []
for i in range(0, len(self.content)):
if state == 'start':
if self.content[i][0] == CHAR_DELIMITER and self.content[i][1] == '<<':
countDirectories += 1
if self.content[i][0] == CHAR_DELIMITER and self.content[i][1] == '>>':
countDirectories -= 1
if countDirectories == 1 and self.content[i][0] == CHAR_DELIMITER and EqualCanonical(self.content[i][1], '/Filter'):
state = 'filter'
elif countDirectories == 0 and self.content[i][0] == CHAR_REGULAR and self.content[i][1] == 'stream':
state = 'stream-whitespace'
elif state == 'filter':
if self.content[i][0] == CHAR_DELIMITER and self.content[i][1][0] == '/':
filters = [self.content[i][1]]
state = 'search-stream'
elif self.content[i][0] == CHAR_DELIMITER and self.content[i][1] == '[':
state = 'filter-list'
elif state == 'filter-list':
if self.content[i][0] == CHAR_DELIMITER and self.content[i][1][0] == '/':
filters.append(self.content[i][1])
elif self.content[i][0] == CHAR_DELIMITER and self.content[i][1] == ']':
state = 'search-stream'
elif state == 'search-stream':
if self.content[i][0] == CHAR_REGULAR and self.content[i][1] == 'stream':
state = 'stream-whitespace'
elif state == 'stream-whitespace':
if self.content[i][0] == CHAR_WHITESPACE:
whitespace = self.content[i][1]
if whitespace.startswith('\x0D\x0A') and len(whitespace) > 2:
data += whitespace[2:]
elif whitespace.startswith('\x0A') and len(whitespace) > 1:
data += whitespace[1:]
else:
data += self.content[i][1]
state = 'stream-concat'
elif state == 'stream-concat':
if self.content[i][0] == CHAR_REGULAR and self.content[i][1] == 'endstream':
if filter:
if overridingfilters == '':
return self.Decompress(data, filters)
elif overridingfilters == 'raw':
return data
else:
return self.Decompress(data, overridingfilters.split(' '))
else:
return data
else:
data += self.content[i][1]
else:
return 'Unexpected filter state'
return filters
def Decompress(self, data, filters):
for filter in filters:
if EqualCanonical(filter, '/FlateDecode') or EqualCanonical(filter, '/Fl'):
try:
data = FlateDecode(data)
except zlib.error as e:
message = 'FlateDecode decompress failed'
if len(data) > 0 and ord(data[0]) & 0x0F != 8:
message += ', unexpected compression method: %02x' % ord(data[0])
return message + '. zlib.error %s' % e.message
elif EqualCanonical(filter, '/ASCIIHexDecode') or EqualCanonical(filter, '/AHx'):
try:
data = ASCIIHexDecode(data)
except:
return 'ASCIIHexDecode decompress failed'
elif EqualCanonical(filter, '/ASCII85Decode') or EqualCanonical(filter, '/A85'):
try:
data = ASCII85Decode(data.rstrip('>'))
except:
return 'ASCII85Decode decompress failed'
elif EqualCanonical(filter, '/LZWDecode') or EqualCanonical(filter, '/LZW'):
try:
data = LZWDecode(data)
except:
return 'LZWDecode decompress failed'
elif EqualCanonical(filter, '/RunLengthDecode') or EqualCanonical(filter, '/R'):
try:
data = RunLengthDecode(data)
except:
return 'RunLengthDecode decompress failed'
# elif i.startswith('/CC') # CCITTFaxDecode
# elif i.startswith('/DCT') # DCTDecode
else:
return 'Unsupported filter: %s' % repr(filters)
if len(filters) == 0:
return 'No filters'
else:
return data
def StreamYARAMatch(self, rules, decoders, decoderoptions, filter, overridingfilters):
if not self.ContainsStream():
return None
streamData = self.Stream(filter, overridingfilters)
if filter and streamData == 'No filters':
streamData = self.Stream(False, overridingfilters)
oDecoders = [cIdentity(streamData, None)]
for cDecoder in decoders:
try:
oDecoder = cDecoder(streamData, decoderoptions)
oDecoders.append(oDecoder)
except Exception as e:
print('Error instantiating decoder: %s' % cDecoder.name)
raise e
results = []
for oDecoder in oDecoders:
while oDecoder.Available():
yaraResults = rules.match(data=oDecoder.Decode())
if yaraResults != []:
results.append([oDecoder.Name(), yaraResults])
return results
class cPDFElementStartxref:
def __init__(self, index):
self.type = PDF_ELEMENT_STARTXREF
self.index = index
class cPDFElementMalformed:
def __init__(self, content):
self.type = PDF_ELEMENT_MALFORMED
self.content = content
def TrimLWhiteSpace(data):
while data != [] and data[0][0] == CHAR_WHITESPACE:
data = data[1:]
return data
def TrimRWhiteSpace(data):
while data != [] and data[-1][0] == CHAR_WHITESPACE:
data = data[:-1]
return data
class cPDFParseDictionary:
def __init__(self, content, nocanonicalizedoutput):
self.content = content
self.nocanonicalizedoutput = nocanonicalizedoutput
dataTrimmed = TrimLWhiteSpace(TrimRWhiteSpace(self.content))
if dataTrimmed == []:
self.parsed = None
elif self.isOpenDictionary(dataTrimmed[0]) and (self.isCloseDictionary(dataTrimmed[-1]) or self.couldBeCloseDictionary(dataTrimmed[-1])):
self.parsed = self.ParseDictionary(dataTrimmed)[0]
else:
self.parsed = None
def isOpenDictionary(self, token):
return token[0] == CHAR_DELIMITER and token[1] == '<<'
def isCloseDictionary(self, token):
return token[0] == CHAR_DELIMITER and token[1] == '>>'
def couldBeCloseDictionary(self, token):
return token[0] == CHAR_DELIMITER and token[1].rstrip().endswith('>>')
def ParseDictionary(self, tokens):
state = 0 # start
dictionary = []
while tokens != []:
if state == 0:
if self.isOpenDictionary(tokens[0]):
state = 1
else:
return None, tokens
elif state == 1:
if self.isOpenDictionary(tokens[0]):
pass
elif self.isCloseDictionary(tokens[0]):
return dictionary, tokens
elif tokens[0][0] != CHAR_WHITESPACE:
key = ConditionalCanonicalize(tokens[0][1], self.nocanonicalizedoutput)
value = []
state = 2
elif state == 2:
if self.isOpenDictionary(tokens[0]):
value, tokens = self.ParseDictionary(tokens)
dictionary.append((key, value))
state = 1
elif self.isCloseDictionary(tokens[0]):
dictionary.append((key, value))
return dictionary, tokens
elif value == [] and tokens[0][0] == CHAR_WHITESPACE:
pass
elif value == [] and tokens[0][1] == '[':
value.append(tokens[0][1])
elif value != [] and value[0] == '[' and tokens[0][1] != ']':
value.append(tokens[0][1])
elif value != [] and value[0] == '[' and tokens[0][1] == ']':
value.append(tokens[0][1])
dictionary.append((key, value))
value = []
state = 1
elif value == [] and tokens[0][1] == '(':
value.append(tokens[0][1])
elif value != [] and value[0] == '(' and tokens[0][1] != ')':
if tokens[0][1][0] == '%':
tokens = [tokens[0]] + cPDFTokenizer(StringIO(tokens[0][1][1:])).Tokens() + tokens[1:]
value.append('%')
else:
value.append(tokens[0][1])
elif value != [] and value[0] == '(' and tokens[0][1] == ')':
value.append(tokens[0][1])
balanced = 0
for item in value:
if item == '(':
balanced += 1
elif item == ')':
balanced -= 1
if balanced < 0 and self.verbose:
print('todo 11: ' + repr(value))
if balanced < 1:
dictionary.append((key, value))
value = []
state = 1
elif value != [] and tokens[0][1][0] == '/':
dictionary.append((key, value))
key = ConditionalCanonicalize(tokens[0][1], self.nocanonicalizedoutput)
value = []
state = 2
else:
value.append(ConditionalCanonicalize(tokens[0][1], self.nocanonicalizedoutput))
tokens = tokens[1:]
return None, tokens
def Retrieve(self):
return self.parsed
def PrettyPrintSubElement(self, prefix, e):
if e[1] == []:
print('%s %s' % (prefix, e[0]))
elif type(e[1][0]) == type(''):
if len(e[1]) == 3 and IsNumeric(e[1][0]) and e[1][1] == '0' and e[1][2] == 'R':
joiner = ' '
else:
joiner = ''
value = joiner.join(e[1]).strip()
reprValue = repr(value)
if "'" + value + "'" != reprValue:
value = reprValue
print('%s %s %s' % (prefix, e[0], value))
else:
print('%s %s' % (prefix, e[0]))
self.PrettyPrintSub(prefix + ' ', e[1])
def PrettyPrintSub(self, prefix, dictionary):
if dictionary != None:
print('%s<<' % prefix)
for e in dictionary:
self.PrettyPrintSubElement(prefix, e)
print('%s>>' % prefix)
def PrettyPrint(self, prefix):
self.PrettyPrintSub(prefix, self.parsed)
def Get(self, select):
for key, value in self.parsed:
if key == select:
return value
return None
def GetNestedSub(self, dictionary, select):
for key, value in dictionary:
if key == select:
return self.PrettyPrintSubElement('', [select, value])
if type(value) == type([]) and len(value) > 0 and type(value[0]) == type((None,)):
result = self.GetNestedSub(value, select)
if result !=None:
return self.PrettyPrintSubElement('', [select, result])
return None
def GetNested(self, select):
return self.GetNestedSub(self.parsed, select)
def FormatOutput(data, raw):
if raw:
if type(data) == type([]):
return ''.join(map(lambda x: x[1], data))
else:
return data
elif sys.version_info[0] > 2:
return ascii(data)
else:
return repr(data)
#Fix for http://bugs.python.org/issue11395
def StdoutWriteChunked(data):
if sys.version_info[0] > 2:
sys.stdout.buffer.write(data)
else:
while data != '':
sys.stdout.write(data[0:10000])
try:
sys.stdout.flush()
except IOError:
return
data = data[10000:]
def IfWIN32SetBinary(io):
if sys.platform == 'win32':
import msvcrt
msvcrt.setmode(io.fileno(), os.O_BINARY)
def PrintOutputObject(object, options):
if options.dump == '-':
filtered = object.Stream(options.filter == True, options.overridingfilters)
if filtered == []:
filtered = ''
IfWIN32SetBinary(sys.stdout)
StdoutWriteChunked(filtered)
return
print('obj %d %d' % (object.id, object.version))
if object.objstm != None:
print(' Containing /ObjStm: %d %d' % object.objstm)
print(' Type: %s' % ConditionalCanonicalize(object.GetType(), options.nocanonicalizedoutput))
print(' Referencing: %s' % ', '.join(map(lambda x: '%s %s %s' % x, object.GetReferences())))
dataPrecedingStream = object.ContainsStream()
oPDFParseDictionary = None
if dataPrecedingStream:
print(' Contains stream')
if options.debug:
print(' %s' % FormatOutput(dataPrecedingStream, options.raw))
oPDFParseDictionary = cPDFParseDictionary(dataPrecedingStream, options.nocanonicalizedoutput)
if options.hash:
streamContent = object.Stream(False, options.overridingfilters)
print(' unfiltered')
print(' len: %6d md5: %s' % (len(streamContent), hashlib.md5(streamContent).hexdigest()))
print(' %s' % HexAsciiDumpLine(streamContent))
streamContent = object.Stream(True, options.overridingfilters)
print(' filtered')
print(' len: %6d md5: %s' % (len(streamContent), hashlib.md5(streamContent).hexdigest()))
print(' %s' % HexAsciiDumpLine(streamContent))
streamContent = None
else:
if options.debug or options.raw:
print(' %s' % FormatOutput(object.content, options.raw))
oPDFParseDictionary = cPDFParseDictionary(object.content, options.nocanonicalizedoutput)
print('')
oPDFParseDictionary.PrettyPrint(' ')
print('')
if options.filter and not options.dump:
filtered = object.Stream(overridingfilters=options.overridingfilters)
if filtered == []:
print(' %s' % FormatOutput(object.content, options.raw))
else:
print(' %s' % FormatOutput(filtered, options.raw))
if options.content:
if object.ContainsStream():
stream = object.Stream(False, options.overridingfilters)
if stream != []:
print(' %s' % FormatOutput(stream, options.raw))
else:
print(''.join([token[1] for token in object.content]))
if options.dump:
filtered = object.Stream(options.filter == True, options.overridingfilters)
if filtered == []:
filtered = ''
try:
fDump = open(options.dump, 'wb')
try:
fDump.write(C2BIP3(filtered))
except:
print('Error writing file %s' % options.dump)
fDump.close()
except:
print('Error writing file %s' % options.dump)
print('')
return
def Canonicalize(sIn):
if sIn == '':
return sIn
elif sIn[0] != '/':
return sIn
elif sIn.find('#') == -1:
return sIn
else:
i = 0
iLen = len(sIn)
sCanonical = ''
while i < iLen:
if sIn[i] == '#' and i < iLen - 2:
try:
sCanonical += chr(int(sIn[i+1:i+3], 16))
i += 2
except:
sCanonical += sIn[i]
else:
sCanonical += sIn[i]
i += 1
return sCanonical
def EqualCanonical(s1, s2):
return Canonicalize(s1) == s2