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format-bytes.py
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#!/usr/bin/env python
__description__ = 'This is essentialy a wrapper for the struct module'
__author__ = 'Didier Stevens'
__version__ = '0.0.10'
__date__ = '2019/11/08'
"""
Source code put in public domain by Didier Stevens, no Copyright
https://DidierStevens.com
Use at your own risk
History:
2016/12/03: start
2017/06/16: refactoring to cBinaryFile
2017/07/11: added CutData
2017/11/04: 0.0.2 refactoring; continued; added options -c & -s
2017/11/18: added option -f
2017/12/01: updated FilenameCheckHash to handle empty file: #
2017/12/10: added manual
2017/12/16: 0.0.3 added epoch to option -f
2017/12/16: 0.0.4 added representation to option -f
2017/12/17: continue
2018/01/02: added extra info for strings when option -f is used
2018/01/15: tweaking string output when option -f is used
2018/01/19: updated man
2018/02/15: 0.0.5 added remainder for option -f
2018/02/18: added option -j
2018/02/19: changed option -j to --jsoninput
2018/02/23: added * remainder to option -f
2018/02/24: updated man
2018/02/26: changed options -c and -s to -C and -S, added options -s -a -x -d, updated man
2018/03/05: updated #e# expressions
2018/06/12: updated man
2018/06/17: added property extracted to cBinaryFile
2018/07/21: updated CheckJSON
2018/10/28: 0.0.6 added option -n
2018/11/09: 0.0.7 added X and S representation for strings; option -A
2018/12/08: updated ParseCutArgument; added selection warning
2019/03/22: 0.0.8 added -F option
2019/03/25: added library & -f name= ; added select remainder (-s r)
2019/04/18: added FiletimeUTC; added support for annotations to library files
2019/07/15: 0.0.9 added tlv format parsing
2019/11/03: 0.0.10 added bitstream support
2019/11/08: added multibits for bitstream
Todo:
"""
import optparse
import sys
import os
import zipfile
import binascii
import random
import gzip
import collections
import glob
import textwrap
import re
import struct
import string
import math
import time
import hashlib
import json
import datetime
if sys.version_info[0] >= 3:
from io import BytesIO as DataIO
else:
from cStringIO import StringIO as DataIO
if sys.version_info[0] >= 3:
from io import StringIO
else:
from cStringIO import StringIO
def PrintManual():
manual = r'''
Manual:
This tool is essentialy a wrapper for the Python module struct.
It reads one or more files or stdin and parses the content according to different formats. This tool is very versatile when it comes to handling files, later full details will be provided.
This Python script was developed with Python 2.7 and tested with Python 2.7 and 3.5.
Example:
format-bytes.py random.bin
File: random.bin
s:signed u:unsigned l:little-endian b:big-endian m:mixed-endian
1I: s -69 u 187
2I: sl 26043 ul 26043 sb -17563 ub 47973
4I: sl 881419707 ul 881419707 sb -1150973644 ub 3143993652
4F: l 0.000000 b -0.003502
4N: b 187.101.137.52 l 52.137.101.187
4E: l 1997/12/06 14:48:27 b 2069/08/17 19:34:12
8I: sl -3535861847371979333 ul 14910882226337572283 sb -4943394157892145458 ub 13503349915817406158
8T: ul N/A ub N/A
8F: l -1661678170725283018588028971660576297715302893638508902075603349019820032.000000 b -0.000000
16G: b BB658934-6218-EECE-3AC3-179F6B7428FB m {348965BB-1862-CEEE-3AC3-179F6B7428FB}
By default, format-bytes.py reads the first 16 bytes (if available) of the file(s) provided as argument, and parses these bytes as:
Integer: I
Float: F
IPv4 address: N
epoch: E
FILETIME: T
GUID: G
1I is a 8-bit integer, 2I is a 16-bit integer, ...
Bytes are interpreted in little-endian (l), big-endian (b) and mixed-endian (m) format. Mixed-endian is only used for GUIDs (G).
Integers can be signed (s) or unsigned (u).
Use option -f to specify how bytes should be parsed: this option takes a Python struct format string.
Example:
format-bytes.py -f "<hib" random.bin
File: random.bin
1: <type 'int'> 26043 65bb 1970/01/01 07:14:03
2: <type 'int'> 409089161 18623489 1982/12/18 19:52:41
3: <type 'int'> -18 -12
String lengths can also be specified in hexadecimal by using prefix 0x. For example, 16s, a 16 character long string, can also be specified as 0x10s in hexadecimal.
End the format string with character * to display remaining bytes.
Example:
format-bytes.py -f "<hib*" random.bin
File: random.bin
1: <type 'int'> 26043 65bb 1970/01/01 07:14:03
2: <type 'int'> 409089161 18623489 1982/12/18 19:52:41
3: <type 'int'> -18 -12
Remainder: 9
00000000: CE 3A C3 17 9F 6B 74 28 FB .:...kt(.
1I: s -50 u 206
2I: sl 15054 ul 15054 sb -12742 ub 52794
4I: sl 398670542 ul 398670542 sb -835009769 ub 3459957527
4F: l 0.000000 b -783336896.000000
4N: b 206.58.195.23 l 23.195.58.206
4E: l 1982/08/20 05:49:02 b 2079/08/22 19:18:47
8I: sl 2915073189858196174 ul 2915073189858196174 sb -3586339647020895192 ub 14860404426688656424
8T: ul N/A ub N/A
8F: l 0.000000 b -721504228050136948830706706079286975060186906491372824967789492043776.000000
You can also specify how the parsed bytes should be represented. To achieve this, append a double colon character (:) to the format string followed by a representation character for each member.
Valid representation characters are X (for hexadecimal), I (for integer), E (for epoch), T (for FILETIME) and S (for string with escaped characters).
Example:
C:\Demo>format-bytes.py -f "<hib*:XEI" random.bin
File: random.bin
1: <type 'int'> 65bb
2: <type 'int'> 1982/12/18 19:52:41
3: <type 'int'> -18
Remainder: 9
00000000: CE 3A C3 17 9F 6B 74 28 FB .:...kt(.
1I: s -50 u 206
2I: sl 15054 ul 15054 sb -12742 ub 52794
4I: sl 398670542 ul 398670542 sb -835009769 ub 3459957527
4F: l 0.000000 b -783336896.000000
4N: b 206.58.195.23 l 23.195.58.206
4E: l 1982/08/20 05:49:02 b 2079/08/22 19:18:47
8I: sl 2915073189858196174 ul 2915073189858196174 sb -3586339647020895192 ub 14860404426688656424
8T: ul N/A ub N/A
8F: l 0.000000 b -721504228050136948830706706079286975060186906491372824967789492043776.000000
For strings, the output will include string length, ASCII representation of the string (first 10 bytes), hexadecimal representation (first 10 bytes), entropy and MD5 hash.
C:\Demo>format-bytes.py -f "<h14s" random.bin
File: random.bin
1: <type 'int'> 26043 65bb 1970/01/01 07:14:03
2: <type 'str'> 14 .4b...:... 89346218eece3ac3179f 3.807355 e1647bd9711cdfee7959dee4ff956590
Strings can be selected with option -s for dumping. Default is ASCII dump (-a), but run-length encoded ASCII (-A), hexadecimal (-x) and binary (-d) dump is available too.
The remainder can also be selected: -s r.
Annotations can be added to particular members, using option -n. Like in this example:
C:\Demo>format-bytes.py -f "<hib*:XEI" -n "2: Creation date 3: Temperature" random.bin
File: random.bin
1: <type 'int'> 65bb
2: <type 'int'> 1982/12/18 19:52:41 Creation date
3: <type 'int'> -18 Temperature
Remainder: 9
00000000: CE 3A C3 17 9F 6B 74 28 FB .:...kt(.
1I: s -50 u 206
2I: sl 15054 ul 15054 sb -12742 ub 52794
4I: sl 398670542 ul 398670542 sb -835009769 ub 3459957527
4F: l 0.000000 b -783336896.000000
4N: b 206.58.195.23 l 23.195.58.206
4E: l 1982/08/20 05:49:02 b 2079/08/22 19:18:47
8I: sl 2915073189858196174 ul 2915073189858196174 sb -3586339647020895192 ub 14860404426688656424
8T: ul N/A ub N/A
8F: l 0.000000 b -721504228050136948830706706079286975060186906491372824967789492043776.000000
This tool can also parse TLV records (Type, Length Value). To achieve this, start the format specifier with tlv= and provide values for format (f:), type (t:) and length (l:) separated by a comma (,).
Like this example:
C:\Demo>format-bytes.py -f "tlv=f:<III,t:0,l:2" registry.blob.bin
File: registry.blob.bin
1: 0x59 18 'R\x00S\x00A\x00/\x00S\x00H\x00A\x001\x0
2: 0x0f 20 'N\x94\xf8r\xf8\x02D\x1e-\x1c\x86\xc4\x0
3: 0x14 20 'F\xcc\x93\x96\xe7\x14k\xaaW\xc7\xc3\r8\
4: 0x02 188 '\x1c\x00\x00\x00\\\x00\x00\x00\x0c\x00\
5: 0x03 20 "\x1c\x9c\xa83\x865\xf1}B\xe4\x1b\x90RH'
6: 0x04 16 "\x86\xae\xa6J'\x19\xc5\xa0\x05\x8a7\x93
7: 0x19 16 "\xa5\x9d~\x05\x03';\x01\x90\xd7fF\xbdd\
8: 0x20 735 '0\x82\x02\xdb0\x82\x01\xc3\xa0\x03\x02\
This command parses the binary blob of a certificate found inside the Windows registry. Each record consists of 3 little-endian 32-bit integers (<III) followed by data. The first integer (index 0), the PropID, is the type (t:0) and the third integer (index 2) is the length (l:2). This is the length of the value (data).
This tool can also extract single bits and join them into a bitstream. To achieve this, start the format specifier with bitstream= and provide values for format (f:), bits (b:) and join (j:) separated by a comma (,).
Like this example:
C:\Demo>format-bytes.py -f "bitstream=f:<H,b:0,j:<" stego.wav
The bytes in file stego.wav are parsed as little-endian, unsigned 16-bit integers (<H) because of format specifier f:<H.
For each integer, the least significant bit is taken (bits specifier b:0) and then joined into bytes from least significant bit to most significant bit (join specifier j:<).
:b can take several bit positions, separated by ;, like this: b:0;1.
:j can be < or >.
Format strings can be stored inside a library file. A library file has the name of the program (format-bytes) and extension .library. Library files can be placed in the same directory as the program, and/or the current directory.
A library file is a text file. Each format string has a name and takes one line: name=formatstring.
Example:
eqn=<HIHIIIIIBBBBBBBBBB40sIIBB*:XXXXXXXXXXXXXXXXXXsXXXX
This defines format string eqn. It can be retrieved with option -f name=eqn.
This format string can be followed by annotations (use a space character to separate the format string and the annotations):
Example:
eqn=<HIHIIIIIBBBBBBBBBB40sIIBB*:XXXXXXXXXXXXXXXXXXsXXXX 1: size of EQNOLEFILEHDR 9: Start MTEF header 14: Full size record 15: Line record 16: Font record 19: Shellcode (fontname)
A line in a library file that starts with # is a comment and is ignored.
FYI, Python struct module format characters are:
Character Byte order
--------------------
@ native
= native
< little-endian
> big-endian
! network (= big-endian)
Format C Type Standard size
-----------------------------------------
x pad byte
c char 1
b signed 1
B unsigned char 1
? _Bool 1
h short 2
H unsigned short 2
i int 4
I unsigned int 4
l long 4
L unsigned long 4
q long long 8
Q unsigned long long 8
f float 4
d double 8
s char[]
p char[]
P void *
To parse a repeating sequence of bytes, use options --count (to specify the number of repetitions) and --step (to specify the number bytes between repeats).
Example:
format-bytes.py -C 2 -S 4 random.bin
File: random.bin
s:signed u:unsigned l:little-endian b:big-endian m:mixed-endian
00 1I: s -69 u 187
00 2I: sl 26043 ul 26043 sb -17563 ub 47973
00 4I: sl 881419707 ul 881419707 sb -1150973644 ub 3143993652
00 4F: l 0.000000 b -0.003502
00 4N: b 187.101.137.52 l 52.137.101.187
00 4E: l 1997/12/06 14:48:27 b 2069/08/17 19:34:12
00 8I: sl -3535861847371979333 ul 14910882226337572283 sb -4943394157892145458 ub 13503349915817406158
00 8T: ul N/A ub N/A
00 8F: l -1661678170725283018588028971660576297715302893638508902075603349019820032.000000 b -0.000000
00 16G: b BB658934-6218-EECE-3AC3-179F6B7428FB m {348965BB-1862-CEEE-3AC3-179F6B7428FB}
04 1I: s 98 u 98
04 2I: sl 6242 ul 6242 sb 25112 ub 25112
04 4I: sl -823256990 ul 3471710306 sb 1645801166 ub 1645801166
04 4F: l -1997287680.000000 b 705278197607520272384.000000
04 4N: b 98.24.238.206 l 206.238.24.98
04 4E: l 2080/01/05 19:58:26 b 2022/02/25 14:59:26
04 8I: sl -6982898039867434910 ul 11463846033842116706 sb 7068662184674531231 ub 7068662184674531231
04 8T: ul N/A ub N/A
04 8F: l -0.000000 b 358946151129582029215291849393230786808315346836706673156033999581834828933214436444158528577134449241373022018959436034143150814561128186558682352782632064229834752.000000
04 16G: b 6218EECE-3AC3-179F-6B74-28FBEB2AD62A m {CEEE1862-C33A-9F17-6B74-28FBEB2AD62A}
To search for a value inside the provided file(s), use option -F. For the moment, only integers can be searched. Start the option value with #i# followed by the decimal number to search for.
Example:
format-bytes.py -F #i#6083 random.bin
File: random.bin
0x00000009 <h 0xc317
0x00000009 <H 0xc317
As stated at the beginning of this manual, this tool is very versatile when it comes to handling files. This will be explained now.
This tool reads files in binary mode. It can read files from disk, from standard input (stdin) and from "generated" files via the command line.
It can also partially read files (this is done with the cut operator).
If no file arguments are provided to this tool, it will read data from standard input (stdin). This way, this tool can be used in a piped chain of commands, like this:
oledump.py -s 4 -d sample.doc.vir | tool.py
This tool can process JSON output from other tools using option --jsoninput:
oledump.py --json sample.doc.vir | tool.py --jsoninput
When one or more file arguments are provided to this tool, it will read the files and process the content.
How the files are read, depends on the type of file arguments that are provided. File arguments that start with character @ or # have special meaning, and will be explained later.
If a file argument does not start with @ or #, it is considered to be a file on disk and the content will be read from disk.
If the file is not a compressed file, the binary content of the file is read from disk for processing.
Compressed files are solely recognized based on their extension: .zip and .gz.
If a file argument with extension .gz is provided, the tool will decompress the gzip file in memory and process the decompressed content. No checks are made to ensure that the file with extension .gz is an actual gzip compressed file.
If a file argument with extension .zip is provided, the tool will extract the first file (or only file) from the ZIP file in memory and process the decompressed content. No checks are made to ensure that the file with extension .zip is an actual ZIP compressed file.
Password protected ZIP files can be processed too. The tool uses password 'infected' (without quotes) as default password. A different password can be provided using option --password.
Example:
tool.py sample.zip
To prevent the tool from decompressing .zip or .gz files, but to process the compressed file itself, use option --noextraction.
File arguments that start with character @ ("here files"), are read as text files that contain file arguments (one per line) to be processed.
For example, we take a text file with filename list.txt and following content:
sample-1.bin
sample-5.bin
sample-7.bin
When using this file (list.txt) in the following command:
tool.py @list.txt
the tool will process the following files: sample-1.bin, sample-5.bin and sample-7.bin.
A single @ character as filename is a here file read from stdin.
Wildcards are supported too. The classic *, ? and [] wildcard characters are supported. For example, use the following command to process all .exe and .dll files in the Windows directory:
tool.py C:\Windows\*.exe C:\Windows\*.dll
To prevent the tool from processing file arguments with wildcard characters or special initial characters (@ and #) differently, but to process them as normal files, use option --literalfilenames.
File arguments that start with character # have special meaning. These are not processed as actual files on disk (except when option --literalfilenames is used), but as file arguments that specify how to "generate" the file content.
File arguments that start with #, #h#, #b# or #e# are used to "generate" the file content.
Arguments that start with #c# are not file arguments, but cut operators (explained later).
Generating the file content with a # file argument means that the file content is not read from disk, but generated in memory based on the characteristics provided via the file argument.
When a file argument starts with # (and not with #h#, #b#, #e# or #c#), all characters that follow the # character specify the content of the generated file.
For example, file argument #ABCDE specifies a file containing exactly 5 bytes: ASCII characters A, B, C, D and E.
Thus the following command:
tool.py #ABCDE
will make the tool process data with binary content ABCDE. #ABCDE is not an actual file written on disk, but it is a notational convention to provide data via the command line.
Since this notation can not be used to specify all possible byte values, hexadecimal encoding (#h#) and BASE64 encoding (#b#) notation is supported too.
For example, #h#4142434445 is an hexadecimal notation that generates data ABCDE. Hexadecimal notation allows the generation of non-printable characters for example, like NULL bytes: #h#00
File argument #b#QUJDREU= is another example, this time BASE64 notation, that generates data ABCDE.
File arguments that start with #e# are a notational convention to use expressions to generate data. An expression is a single function/string or the concatenation of several functions/strings (using character + as concatenation operator).
Strings can be characters enclosed by single quotes ('example') or hexadecimal strings prefixed by 0x (0xBEEF).
4 functions are available: random, loremipsum, repeat and chr.
Function random takes exactly one argument: an integer (with value 1 or more). Integers can be specified using decimal notation or hexadecimal notation (prefix 0x).
The random function generates a sequence of bytes with a random value (between 0 and 255), the argument specifies how many bytes need to be generated. Remark that the random number generator that is used is just the Python random number generator, not a cryptographic random number generator.
Example:
tool.py #e#random(100)
will make the tool process data consisting of a sequence of 100 random bytes.
Function loremipsum takes exactly one argument: an integer (with value 1 or more).
The loremipsum function generates "lorem ipsum" text (fake latin), the argument specifies the number of sentences to generate.
Example: #e#loremipsum(2) generates this text:
Ipsum commodo proin pulvinar hac vel nunc dignissim neque eget odio erat magna lorem urna cursus fusce facilisis porttitor congue eleifend taciti. Turpis duis suscipit facilisi tristique dictum praesent natoque sem mi egestas venenatis per dui sit sodales est condimentum habitasse ipsum phasellus non bibendum hendrerit.
Function chr takes one argument or two arguments.
chr with one argument takes an integer between 0 and 255, and generates a single byte with the value specified by the integer.
chr with two arguments takes two integers between 0 and 255, and generates a byte sequence with the values specified by the integers.
For example #e#chr(0x41,0x45) generates data ABCDE.
Function repeat takes two arguments: an integer (with value 1 or more) and a byte sequence. This byte sequence can be a quoted string of characters (single quotes), like 'ABCDE' or an hexadecimal string prefixed with 0x, like 0x4142434445.
The repeat function will create a sequence of bytes consisting of the provided byte sequence (the second argument) repeated as many times as specified by the first argument.
For example, #e#repeat(3, 'AB') generates byte sequence ABABAB.
When more than one function needs to be used, the byte sequences generated by the functions can be concatenated with the + operator.
For example, #e#repeat(10,0xFF)+random(100) will generate a byte sequence of 10 FF bytes followed by 100 random bytes.
The cut argument (or cut operator) allows for the partial selection of the content of a file. This argument starts with #c# followed by a "cut-expression". Use this expression to "cut out" part of the content.
The cut-argument must be put in front of a file argument, like in this example:
tool.py #c#0:100l data.bin
With these arguments, tool.py will only process the first 100 bytes (0:100l) of file data.bin.
A cut argument is applied to all file arguments that follow it. Example:
tool.py #c#0:100l data-1.bin data-2.bin
With these arguments, tool.py will only process the first 100 bytes (0:100l) of file data-1.bin and the first 100 bytes file data-2.bin.
More than one cut argument can be used, like in this example:
tool.py #c#0:100l data-1.bin #c#0:200l data-2.bin
With these arguments, tool.py will only process the first 100 bytes (0:100l) of file data-1.bin and the first 200 bytes (0:200l) of file data-2.bin.
A cut-expression is composed of 2 terms separated by a colon (:), like this:
termA:termB
termA and termB can be:
- nothing (an empty string)
- a positive decimal number; example: 10
- an hexadecimal number (to be preceded by 0x); example: 0x10
- a case sensitive string to search for (surrounded by square brackets and single quotes); example: ['MZ']
- an hexadecimal string to search for (surrounded by square brackets); example: [d0cf11e0]
If termA is nothing, then the cut section of bytes starts with the byte at position 0.
If termA is a number, then the cut section of bytes starts with the byte at the position given by the number (first byte has index 0).
If termA is a string to search for, then the cut section of bytes starts with the byte at the position where the string is first found. If the string is not found, the cut is empty (0 bytes).
If termB is nothing, then the cut section of bytes ends with the last byte.
If termB is a number, then the cut section of bytes ends with the byte at the position given by the number (first byte has index 0).
When termB is a number, it can have suffix letter l. This indicates that the number is a length (number of bytes), and not a position.
termB can also be a negative number (decimal or hexademical): in that case the position is counted from the end of the file. For example, :-5 selects the complete file except the last 5 bytes.
If termB is a string to search for, then the cut section of bytes ends with the last byte at the position where the string is first found. If the string is not found, the cut is empty (0 bytes).
No checks are made to assure that the position specified by termA is lower than the position specified by termB. This is left up to the user.
Search string expressions (ASCII and hexadecimal) can be followed by an instance (a number equal to 1 or greater) to indicate which instance needs to be taken. For example, ['ABC']2 will search for the second instance of string 'ABC'. If this instance is not found, then nothing is selected.
Search string expressions (ASCII and hexadecimal) can be followed by an offset (+ or - a number) to add (or substract) an offset to the found instance. For example, ['ABC']+3 will search for the first instance of string 'ABC' and then select the bytes after ABC (+ 3).
Finally, search string expressions (ASCII and hexadecimal) can be followed by an instance and an offset.
Examples:
This cut-expression can be used to dump the first 256 bytes of a PE file located inside the file content: ['MZ']:0x100l
This cut-expression can be used to dump the OLE file located inside the file content: [d0cf11e0]:
'''
for line in manual.split('\n'):
print(textwrap.fill(line, 79))
LIBRARY_EXTENSION = '.library'
KEYWORD_FORMAT = 'format'
KEYWORD_TLV = 'tlv'
KEYWORD_TYPE = 'type'
KEYWORD_LENGTH = 'length'
KEYWORD_BITSTREAM = 'bitstream'
KEYWORD_BITS = 'bits'
KEYWORD_JOIN = 'join'
dLibrary = {}
#Convert 2 Bytes If Python 3
def C2BIP3(string):
if sys.version_info[0] > 2:
return bytes([ord(x) for x in string])
else:
return string
#Convert 2 Integer If Python 2
def C2IIP2(data):
if sys.version_info[0] > 2:
return data
else:
return ord(data)
# 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 RINSub(data, specialcharacters=''):
if specialcharacters != '':
for specialcharacter in specialcharacters:
if specialcharacter in data:
return repr(data)
return data
elif "'" + data + "'" == repr(data):
return data
else:
return repr(data)
# RIN: Repr If Needed
def RIN(data, specialcharacters=''):
if type(data) == list:
return [RINSub(item, specialcharacters) for item in data]
else:
return RINSub(data, specialcharacters)
#----------------------------------------------------------------------------------------------------
#import random
#import binascii
#import zipfile
#import gzip
#import sys
#if sys.version_info[0] >= 3:
# from io import BytesIO as DataIO
#else:
# from cStringIO import StringIO as DataIO
def LoremIpsumSentence(minimum, maximum):
words = ['lorem', 'ipsum', 'dolor', 'sit', 'amet', 'consectetur', 'adipiscing', 'elit', 'etiam', 'tortor', 'metus', 'cursus', 'sed', 'sollicitudin', 'ac', 'sagittis', 'eget', 'massa', 'praesent', 'sem', 'fermentum', 'dignissim', 'in', 'vel', 'augue', 'scelerisque', 'auctor', 'libero', 'nam', 'a', 'gravida', 'odio', 'duis', 'vestibulum', 'vulputate', 'quam', 'nec', 'cras', 'nibh', 'feugiat', 'ut', 'vitae', 'ornare', 'justo', 'orci', 'varius', 'natoque', 'penatibus', 'et', 'magnis', 'dis', 'parturient', 'montes', 'nascetur', 'ridiculus', 'mus', 'curabitur', 'nisl', 'egestas', 'urna', 'iaculis', 'lectus', 'maecenas', 'ultrices', 'velit', 'eu', 'porta', 'hac', 'habitasse', 'platea', 'dictumst', 'integer', 'id', 'commodo', 'mauris', 'interdum', 'malesuada', 'fames', 'ante', 'primis', 'faucibus', 'accumsan', 'pharetra', 'aliquam', 'nunc', 'at', 'est', 'non', 'leo', 'nulla', 'sodales', 'porttitor', 'facilisis', 'aenean', 'condimentum', 'rutrum', 'facilisi', 'tincidunt', 'laoreet', 'ultricies', 'neque', 'diam', 'euismod', 'consequat', 'tempor', 'elementum', 'lobortis', 'erat', 'ligula', 'risus', 'donec', 'phasellus', 'quisque', 'vivamus', 'pellentesque', 'tristique', 'venenatis', 'purus', 'mi', 'dictum', 'posuere', 'fringilla', 'quis', 'magna', 'pretium', 'felis', 'pulvinar', 'lacinia', 'proin', 'viverra', 'lacus', 'suscipit', 'aliquet', 'dui', 'molestie', 'dapibus', 'mollis', 'suspendisse', 'sapien', 'blandit', 'morbi', 'tellus', 'enim', 'maximus', 'semper', 'arcu', 'bibendum', 'convallis', 'hendrerit', 'imperdiet', 'finibus', 'fusce', 'congue', 'ullamcorper', 'placerat', 'nullam', 'eros', 'habitant', 'senectus', 'netus', 'turpis', 'luctus', 'volutpat', 'rhoncus', 'mattis', 'nisi', 'ex', 'tempus', 'eleifend', 'vehicula', 'class', 'aptent', 'taciti', 'sociosqu', 'ad', 'litora', 'torquent', 'per', 'conubia', 'nostra', 'inceptos', 'himenaeos']
sample = random.sample(words, random.randint(minimum, maximum))
sample[0] = sample[0].capitalize()
return ' '.join(sample) + '.'
def LoremIpsum(sentences):
return ' '.join([LoremIpsumSentence(15, 30) for i in range(sentences)])
STATE_START = 0
STATE_IDENTIFIER = 1
STATE_STRING = 2
STATE_SPECIAL_CHAR = 3
STATE_ERROR = 4
FUNCTIONNAME_REPEAT = 'repeat'
FUNCTIONNAME_RANDOM = 'random'
FUNCTIONNAME_CHR = 'chr'
FUNCTIONNAME_LOREMIPSUM = 'loremipsum'
def Tokenize(expression):
result = []
token = ''
state = STATE_START
while expression != '':
char = expression[0]
expression = expression[1:]
if char == "'":
if state == STATE_START:
state = STATE_STRING
elif state == STATE_IDENTIFIER:
result.append([STATE_IDENTIFIER, token])
state = STATE_STRING
token = ''
elif state == STATE_STRING:
result.append([STATE_STRING, token])
state = STATE_START
token = ''
elif char >= '0' and char <= '9' or char.lower() >= 'a' and char.lower() <= 'z':
if state == STATE_START:
token = char
state = STATE_IDENTIFIER
else:
token += char
elif char == ' ':
if state == STATE_IDENTIFIER:
result.append([STATE_IDENTIFIER, token])
token = ''
state = STATE_START
elif state == STATE_STRING:
token += char
else:
if state == STATE_IDENTIFIER:
result.append([STATE_IDENTIFIER, token])
token = ''
state = STATE_START
result.append([STATE_SPECIAL_CHAR, char])
elif state == STATE_STRING:
token += char
else:
result.append([STATE_SPECIAL_CHAR, char])
token = ''
if state == STATE_IDENTIFIER:
result.append([state, token])
elif state == STATE_STRING:
result = [[STATE_ERROR, 'Error: string not closed', token]]
return result
def ParseFunction(tokens):
if len(tokens) == 0:
print('Parsing error')
return None, tokens
if tokens[0][0] == STATE_STRING or tokens[0][0] == STATE_IDENTIFIER and tokens[0][1].startswith('0x'):
return [[FUNCTIONNAME_REPEAT, [[STATE_IDENTIFIER, '1'], tokens[0]]], tokens[1:]]
if tokens[0][0] != STATE_IDENTIFIER:
print('Parsing error')
return None, tokens
function = tokens[0][1]
tokens = tokens[1:]
if len(tokens) == 0:
print('Parsing error')
return None, tokens
if tokens[0][0] != STATE_SPECIAL_CHAR or tokens[0][1] != '(':
print('Parsing error')
return None, tokens
tokens = tokens[1:]
if len(tokens) == 0:
print('Parsing error')
return None, tokens
arguments = []
while True:
if tokens[0][0] != STATE_IDENTIFIER and tokens[0][0] != STATE_STRING:
print('Parsing error')
return None, tokens
arguments.append(tokens[0])
tokens = tokens[1:]
if len(tokens) == 0:
print('Parsing error')
return None, tokens
if tokens[0][0] != STATE_SPECIAL_CHAR or (tokens[0][1] != ',' and tokens[0][1] != ')'):
print('Parsing error')
return None, tokens
if tokens[0][0] == STATE_SPECIAL_CHAR and tokens[0][1] == ')':
tokens = tokens[1:]
break
tokens = tokens[1:]
if len(tokens) == 0:
print('Parsing error')
return None, tokens
return [[function, arguments], tokens]
def Parse(expression):
tokens = Tokenize(expression)
if len(tokens) == 0:
print('Parsing error')
return None
if tokens[0][0] == STATE_ERROR:
print(tokens[0][1])
print(tokens[0][2])
print(expression)
return None
functioncalls = []
while True:
functioncall, tokens = ParseFunction(tokens)
if functioncall == None:
return None
functioncalls.append(functioncall)
if len(tokens) == 0:
return functioncalls
if tokens[0][0] != STATE_SPECIAL_CHAR or tokens[0][1] != '+':
print('Parsing error')
return None
tokens = tokens[1:]
def InterpretInteger(token):
if token[0] != STATE_IDENTIFIER:
return None
try:
return int(token[1])
except:
return None
def Hex2Bytes(hexadecimal):
if len(hexadecimal) % 2 == 1:
hexadecimal = '0' + hexadecimal
try:
return binascii.a2b_hex(hexadecimal)
except:
return None
def InterpretHexInteger(token):
if token[0] != STATE_IDENTIFIER:
return None
if not token[1].startswith('0x'):
return None
bytes = Hex2Bytes(token[1][2:])
if bytes == None:
return None
integer = 0
for byte in bytes:
integer = integer * 0x100 + C2IIP2(byte)
return integer
def InterpretNumber(token):
number = InterpretInteger(token)
if number == None:
return InterpretHexInteger(token)
else:
return number
def InterpretBytes(token):
if token[0] == STATE_STRING:
return token[1]
if token[0] != STATE_IDENTIFIER:
return None
if not token[1].startswith('0x'):
return None
return Hex2Bytes(token[1][2:])
def CheckFunction(functionname, arguments, countarguments, maxcountarguments=None):
if maxcountarguments == None:
if countarguments == 0 and len(arguments) != 0:
print('Error: function %s takes no arguments, %d are given' % (functionname, len(arguments)))
return True
if countarguments == 1 and len(arguments) != 1:
print('Error: function %s takes 1 argument, %d are given' % (functionname, len(arguments)))
return True
if countarguments != len(arguments):
print('Error: function %s takes %d arguments, %d are given' % (functionname, countarguments, len(arguments)))
return True
else:
if len(arguments) < countarguments or len(arguments) > maxcountarguments:
print('Error: function %s takes between %d and %d arguments, %d are given' % (functionname, countarguments, maxcountarguments, len(arguments)))
return True
return False
def CheckNumber(argument, minimum=None, maximum=None):
number = InterpretNumber(argument)
if number == None:
print('Error: argument should be a number: %s' % argument[1])
return None
if minimum != None and number < minimum:
print('Error: argument should be minimum %d: %d' % (minimum, number))
return None
if maximum != None and number > maximum:
print('Error: argument should be maximum %d: %d' % (maximum, number))
return None
return number
def Interpret(expression):
functioncalls = Parse(expression)
if functioncalls == None:
return None
decoded = ''
for functioncall in functioncalls:
functionname, arguments = functioncall
if functionname == FUNCTIONNAME_REPEAT:
if CheckFunction(functionname, arguments, 2):
return None
number = CheckNumber(arguments[0], minimum=1)
if number == None:
return None
bytes = InterpretBytes(arguments[1])
if bytes == None:
print('Error: argument should be a byte sequence: %s' % arguments[1][1])
return None
decoded += number * bytes
elif functionname == FUNCTIONNAME_RANDOM:
if CheckFunction(functionname, arguments, 1):
return None
number = CheckNumber(arguments[0], minimum=1)
if number == None:
return None
decoded += ''.join([chr(random.randint(0, 255)) for x in range(number)])
elif functionname == FUNCTIONNAME_LOREMIPSUM:
if CheckFunction(functionname, arguments, 1):
return None
number = CheckNumber(arguments[0], minimum=1)
if number == None:
return None
decoded += LoremIpsum(number)
elif functionname == FUNCTIONNAME_CHR:
if CheckFunction(functionname, arguments, 1, 2):
return None
number = CheckNumber(arguments[0], minimum=1, maximum=255)
if number == None:
return None
if len(arguments) == 1:
decoded += chr(number)
else:
number2 = CheckNumber(arguments[1], minimum=1, maximum=255)
if number2 == None:
return None
decoded += ''.join([chr(n) for n in range(number, number2 + 1)])
else:
print('Error: unknown function: %s' % functionname)
return None
return decoded
FCH_FILENAME = 0
FCH_DATA = 1
FCH_ERROR = 2
def FilenameCheckHash(filename, literalfilename):
if literalfilename:
return FCH_FILENAME, filename
elif filename.startswith('#h#'):
result = Hex2Bytes(filename[3:])
if result == None:
return FCH_ERROR, 'hexadecimal'
else:
return FCH_DATA, result
elif filename.startswith('#b#'):
try:
return FCH_DATA, binascii.a2b_base64(filename[3:])
except:
return FCH_ERROR, 'base64'
elif filename.startswith('#e#'):
result = Interpret(filename[3:])
if result == None:
return FCH_ERROR, 'expression'
else:
return FCH_DATA, result
elif filename.startswith('#'):
return FCH_DATA, C2BIP3(filename[1:])
else:
return FCH_FILENAME, filename
class cBinaryFile:
def __init__(self, filename, zippassword='infected', noextraction=False, literalfilename=False, content=None):
self.filename = filename
self.zippassword = zippassword
self.noextraction = noextraction
self.literalfilename = literalfilename
self.oZipfile = None
self.extracted = False
if content != None:
self.fIn = DataIO(content)
return
fch, data = FilenameCheckHash(self.filename, self.literalfilename)
if fch == FCH_ERROR:
raise Exception('Error %s parsing filename: %s' % (data, self.filename))
if self.filename == '':
if sys.platform == 'win32':
import msvcrt
msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
self.fIn = sys.stdin
elif fch == FCH_DATA:
self.fIn = DataIO(data)
elif not self.noextraction and self.filename.lower().endswith('.zip'):
self.oZipfile = zipfile.ZipFile(self.filename, 'r')
if len(self.oZipfile.infolist()) == 1:
self.fIn = self.oZipfile.open(self.oZipfile.infolist()[0], 'r', self.zippassword)
self.extracted = True
else:
self.oZipfile.close()
self.oZipfile = None
self.fIn = open(self.filename, 'rb')
elif not self.noextraction and self.filename.lower().endswith('.gz'):
self.fIn = gzip.GzipFile(self.filename, 'rb')
self.extracted = True
else:
self.fIn = open(self.filename, 'rb')
def close(self):
if self.fIn != sys.stdin:
self.fIn.close()
if self.oZipfile != None:
self.oZipfile.close()
def read(self, size=None):
try:
fRead = self.fIn.buffer
except:
fRead = self.fIn
if size == None:
return fRead.read()
else:
return fRead.read(size)
def Data(self):
data = self.fIn.read()
self.close()
return data
#----------------------------------------------------------------------------------------------------
def File2Strings(filename):
try:
if filename == '':
f = sys.stdin
else:
f = open(filename, 'r')
except:
return None
try:
return map(lambda line:line.rstrip('\n'), f.readlines())
except:
return None
finally:
if f != sys.stdin:
f.close()
def ProcessAt(argument):
if argument.startswith('@'):
strings = File2Strings(argument[1:])
if strings == None:
raise Exception('Error reading %s' % argument)
else:
return strings
else:
return [argument]
def Glob(filename):
filenames = glob.glob(filename)
if len(filenames) == 0:
return [filename]
else:
return filenames
def ExpandFilenameArguments(filenames, literalfilenames=False):
if len(filenames) == 0:
return [['', '']]
elif literalfilenames:
return [[filename, ''] for filename in filenames]
else:
cutexpression = ''
result = []
for filename in list(collections.OrderedDict.fromkeys(sum(map(Glob, sum(map(ProcessAt, filenames), [])), []))):
if filename.startswith('#c#'):
cutexpression = filename[3:]
else:
result.append([filename, cutexpression])
if result == []:
return [['', cutexpression]]
return result
def CheckJSON(stringJSON):
try:
object = json.loads(stringJSON)
except:
print('Error parsing JSON')
print(sys.exc_info()[1])
return None
if not isinstance(object, dict):
print('Error JSON is not a dictionary')
return None
if not 'version' in object:
print('Error JSON dictionary has no version')
return None
if object['version'] != 2:
print('Error JSON dictionary has wrong version')
return None
if not 'id' in object:
print('Error JSON dictionary has no id')
return None
if object['id'] != 'didierstevens.com':
print('Error JSON dictionary has wrong id')
return None
if not 'type' in object:
print('Error JSON dictionary has no type')
return None
if object['type'] != 'content':
print('Error JSON dictionary has wrong type')
return None
if not 'fields' in object:
print('Error JSON dictionary has no fields')
return None
if not 'name' in object['fields']:
print('Error JSON dictionary has no name field')
return None
if not 'content' in object['fields']:
print('Error JSON dictionary has no content field')
return None
if not 'items' in object:
print('Error JSON dictionary has no items')
return None
for item in object['items']:
item['content'] = binascii.a2b_base64(item['content'])
return object['items']
def GenerateFileList(args, options):
if len(args) > 0 and options.jsoninput:
print('Error: option -j can not be used with files')
return None
result = []
if options.jsoninput:
items = CheckJSON(sys.stdin.read())
if items == None:
return None
for item in items:
result.append((item['name'], '', item['content']))
else:
for filename, cutexpression in ExpandFilenameArguments(args, options.literalfilenames):
result.append((filename, cutexpression, None))
return result
CUTTERM_NOTHING = 0
CUTTERM_POSITION = 1
CUTTERM_FIND = 2
CUTTERM_LENGTH = 3
def Replace(string, dReplacements):
if string in dReplacements:
return dReplacements[string]
else:
return string
def ParseInteger(argument):
sign = 1
if argument.startswith('+'):
argument = argument[1:]
elif argument.startswith('-'):
argument = argument[1:]