Rust-Obfuscator

rust-obfuscator is a set of tools designed to automatically obfuscate Rust source code by inserting procedural macros or by (optionally) providing the obfuscation in the source code directly. For more fine-grained obfuscation a procedural macro library cryptify is also provided.

Currently Supported

1. string literal encryption
2. control-flow obfuscation
3. control-flow obfuscation (source code)
4. variable renaming (source code)

Features

• String Encryption: Automatically encrypts string literals assigned to local variables at compile time.
  • Can also be used for formatted strings, but currently requires manual placement

      println!("{}", cryptify::encrypt_string!("hello!"));

• Control Flow Obfuscation: Introduces compile-dummy dummy loops and random variables.
• Customizable Obfuscation: Offers flexibility to enable or disable specific obfuscation features based on your requirements.
• Variable Renaming: Obfuscation of the source code directly, if you'd like to ship the code or just want to make your code look worse.

Installation

Add cryptify to your Cargo.toml as a dependency:

[dependencies]
cryptify = "3.1.1"

To install rust-obfuscator, clone the repository and build the tool using Cargo from the root:

cargo build --release --bin rust-obfuscator

The binary can then be found under /target/release, you can copy it to the root of the project like such

cp ./target/release/rust-obfuscator .

Usage

Set the CRYPTIFY_KEY environment variable for custom encryption otherwise it defaults to defined fixed key

• Add to source code you'd like to modify

use cryptify;

The binary can be used on either a file or a directory. If provided with a directory it will only modify rust source files within that directory not any subdirectories

./rust-obfuscator path/to/your_project <Options>

• All Obfuscated code will be under the obfuscated_code directory that is created from the directory the tool was run.
• Recommended to use a Rust Formatter with the obfuscated code as syn naturally modifies the structure and it will be written to the file as one line

Option Flags

• --no_string: Disables string obfuscation.
• --no_flow: Disables control flow obfuscation.
• --disable_macro: Uses direct source manipulation for flow obfuscation instead of procedural macros.
• --var: Enables variable renaming source code obfuscation.

Example usage with flag

rust-obfuscator path/to/your_project --no_flow 

(disables flow obfuscation)

Input

-running the tool with no config

use cryptify;
mod word_counter;
use std::env;
use std::fs;
use word_counter::count_words;
fn main() {
    let b = "Hello World";
    println!("{}", b);
    let args: Vec<String> = env::args().collect();
    if args.len() < 2 {
        eprintln!("Usage: {} <filename>", args[0]);
        return;
    }
    let filename = &args[1];
    let content = fs::read_to_string(filename).expect("Could not read file");
    let word_counts = count_words(&content);
    for (word, count) in word_counts.iter() {
        println!("{}: {}", word, count);
    }
}

fn dummy() {
    let a = 1;
    let b = 2;
    let c = a + b;
    println!("{}", c);
}

fn calc_sum(a: i32, b: i32) -> i32 {
    cryptify::flow_stmt!();
    let c = a + b;
    c
}

fn helloooo(){
    println!("hi");
}

Output

fn main() {
    cryptify::flow_stmt!();
    let b = cryptify::encrypt_string!("Hello World");
    println!("{}", b);
    let args: Vec<String> = env::args().collect();
    if args.len() < 2 {
        eprintln!("Usage: {} <filename>", args[0]);
        return;
    }
    let filename = &args[1];
    let content = fs::read_to_string(filename).expect("Could not read file");
    let word_counts = count_words(&content);
    for (word, count) in word_counts.iter() {
        println!("{}: {}", word, count);
    }
}
fn dummy() {
    cryptify::flow_stmt!();
    let a = 1;
    let b = 2;
    let c = a + b;
    println!("{}", c);
}
fn calc_sum(a: i32, b: i32) -> i32 {
    cryptify::flow_stmt!();
    let c = a + b;
    c
}
fn helloooo() {
    println!("hi");
}

Expanded Output

fn main() {
    {
        let _is_dummy_145 = true;
        let _dummy_upper_bound = 100;
        let _random_dummy_var = 1;
        let mut _dummy_counter = 6i32;
        let _dummy_increment = 2i32;
        loop {
            if _dummy_counter > _dummy_upper_bound {
                break;
            }
            unsafe {
                std::ptr::write_volatile(
                    &mut _dummy_counter,
                    _dummy_counter + _dummy_increment,
                );
            }
        }
    };
    let b = cryptify::decrypt_string("0\u{b}\r\u{1f}\tFd\u{18}\u{11}\t\0");
    {
        ::std::io::_print(format_args!("{0}\n", b));
    };
    let args: Vec<String> = env::args().collect();
    if args.len() < 2 {
        {
            ::std::io::_eprint(format_args!("Usage: {0} <filename>\n", args[0]));
        };
        return;
    }
    let filename = &args[1];
    let content = fs::read_to_string(filename).expect("Could not read file");
    let word_counts = count_words(&content);
    for (word, count) in word_counts.iter() {
        {
            ::std::io::_print(format_args!("{0}: {1}\n", word, count));
        };
    }
}
fn dummy() {
    {
        let _is_dummy_145 = true;
        let mut _dummy_counter = 4i32;
        let _dummy_upper_bound = 100;
        let _dummy_increment = 3i32;
        loop {
            if _dummy_counter > _dummy_upper_bound {
                break;
            }
            unsafe {
                std::ptr::write_volatile(
                    &mut _dummy_counter,
                    _dummy_counter + _dummy_increment,
                );
            }
        }
    };
    let a = 1;
    let b = 2;
    let c = a + b;
    {
        ::std::io::_print(format_args!("{0}\n", c));
    };
}
fn calc_sum(a: i32, b: i32) -> i32 {
    {
        let _is_dummy_145 = true;
        let mut _dummy_counter = 8i32;
        let _dummy_increment = 3i32;
        let _extra_dummy_var = 4i32;
        let _dummy_upper_bound = 100;
        loop {
            if _dummy_counter > _dummy_upper_bound {
                break;
            }
            unsafe {
                std::ptr::write_volatile(
                    &mut _dummy_counter,
                    _dummy_counter + _dummy_increment,
                );
            }
        }
    };
    let c = a + b;
    c
}
fn helloooo() {
    {
        ::std::io::_print(format_args!("hi\n"));
    };
}

License

rust-obfuscator is licensed under the MIT License - see the LICENSE file for details.