Binary String Toolkit
Summary
The Binary String Toolkit or BST for short is a rather simple utility to convert binary strings to various formats suitable for inclusions in source codes, such as those used to develop exploits and Proof of Concepts in the security field.
Features
- Convert and dump binary files to standard output in a binary string format.
- Convert a plain hexadecimal input string to a hex escaped version.
- Generate a sequence of bad characters for detecting bad chars in buffers.
- Limit the width of binary strings for a better readability of your exploit codes.
- Format binary strings in your favorite programming or scripting language’s syntax, such as:
- Perform automatic variable block indentation ready for copy/paste inclusions.
Install
$ git clone https://github.com/e3prom/bst
$ cd bst
$ make
# by default, bstrings is installed in /usr/local/bin.
$ sudo make install
Usage
The below example shows how an assembled shellcode can be quickly dumped (-D) to standard output in a hexadecimal escaped (-x) binary string of 16 hexadecimal digits width (or 8 bytes), with Python syntax formatting and an indentation level of 4 space characters:
The below example show how an assembled shellcode can be quickly dumped (-D) to standard output in a hexadecimal escaped (-x) binary string of 16 hexadecimal digits width (or 8 bytes), with Python syntax formatting and an indentation level of 4 space characters:
You can also use bstrings to output an automatically indented bad character sequence, and thus in your favorite programming language:
$ bstrings --verbose -b -w12 -i 4 --syntax=c -n badchar
[*] Generating bad character binary string.
[+] Binary string width is limited to 12 bytes.
unsigned char badchar[] =
"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c"
"\x0d\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18"
"\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20\x21\x22\x23\x24"
"\x25\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f\x30"
"\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3a\x3b\x3c"
"\x3d\x3e\x3f\x40\x41\x42\x43\x44\x45\x46\x47\x48"
"\x49\x4a\x4b\x4c\x4d\x4e\x4f\x50\x51\x52\x53\x54"
"\x55\x56\x57\x58\x59\x5a\x5b\x5c\x5d\x5e\x5f\x60"
"\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6a\x6b\x6c"
"\x6d\x6e\x6f\x70\x71\x72\x73\x74\x75\x76\x77\x78"
"\x79\x7a\x7b\x7c\x7d\x7e\x7f\x80\x81\x82\x83\x84"
"\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90"
"\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c"
"\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8"
"\xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\xb2\xb3\xb4"
"\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0"
"\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc"
"\xcd\xce\xcf\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8"
"\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4"
"\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0"
"\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc"
"\xfd\xfe\xff"
Copyright (C) 2018 e3prom
Source: https://github.com/e3prom/bst