hstrings is a command-line tool for finding and displaying hidden continuous sequences of printable characters within a binary file or stdin input. The tool rotates the input bytes using various left-right rotations and XOR operations before searching for printable character sequences. The output is color-coded for each type of operation.

To compile the program, simply run:

make

To use the program with a binary file, run:

./hstrings <binary_file>

To use the program with input from stdin, run:

./hstrings < input_file

or

cat input_file | ./hstrings

The program will print continuous sequences of printable characters that are 3 characters or longer on separate lines. The output is color-coded based on the type of rotation applied to the input bytes:

• Red: Left rotations (ROL)
• Blue: Right rotations (ROR)
• Green: XOR operation

Before each set of sequences, the program prints the rotation type and the number of bits rotated, in the format ROL-X, ROR-X or XOR-X where X is the number of bits or key used.

Suppose you have a binary file named sample.bin. To use the hstrings tool on this file, run:

./hstrings sample.bin

The program will display the continuous sequences of printable characters for each rotation:

ROL-4:
(sequence 1)
(sequence 2)
...
ROR-1:
(sequence 1)
(sequence 2)
...
XOR-0x4F:
(sequence 1)
(sequence 2)
...

To install the program, run:

make install

This command will install the hstrings tool to /usr/local/bin. You may need to run sudo make install to install with the required permissions.

To uninstall the program, run:

make uninstall

This command will remove the hstrings tool from /usr/local/bin. You may need to run sudo make uninstall to remove the program with the required permissions.

Copyright (C) 2023 Dimitrios Vlastaras. All rights reserved.

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