soft-aes-wasm

This project provides a WebAssembly (Wasm) interface for the soft-aes Rust library, allowing for AES encryption and decryption directly in web applications. It includes support for AES ECB and AES CBC modes and integrated Cipher-based Message Authentication Code (AES-CMAC) calculation.

The library includes support for PKCS#7 padding and 0x80 padding (ISO/IEC 9797-1 Padding Method 2).

IMPORTANT: This implementation currently does not incorporate defenses against side-channel attacks. Consequently, Soft-AES is optimally positioned for educational purposes and non-critical application scenarios where such advanced protections are not a primary concern.

Table of Contents

• Installation with npm
• Building from Source
• Usage
• Test
• Related Projects
  • soft-aes
  • Web UI
• License

Installation with npm

To integrate soft-aes-wasm in your web project using npm, follow these steps:

1. Add the soft-aes-wasm package to your project:

   npm install soft-aes-wasm

2. Import and initialize the module in your custom JavaScript file:

   import init, {
      wasm_aes_enc_ecb,
      wasm_aes_dec_ecb,
      wasm_aes_enc_cbc,
      wasm_aes_dec_cbc,
      wasm_aes_cmac
    } from "path/to/pkg/soft_aes_wasm.js";
   
   async function run() {
       await init(); // Initialize the wasm module
   
       // Implement your AES logic here...
   }
   
   run();

Building from Source

If you want to build the Wasm module from the source, clone the repository and run wasm-pack:

git clone https://github.com/5n00py/soft-aes-wasm.git
cd soft-aes-wasm
wasm-pack build --target web

Usage

This is a basic example of how to use the AES ECB and CBC functions:

// AES ECB
const plaintext = new TextEncoder().encode("Example plaintext.");
const key = new TextEncoder().encode("Very secret key.");
const encryptedEcb = wasm_aes_enc_ecb(plaintext, key, "PKCS7");
const decryptedEcb = wasm_aes_dec_ecb(encryptedEcb, key, "PKCS7");

// AES CBC
const key = new TextEncoder().encode("Very secret key.");
const iv = new TextEncoder().encode("Random Init Vec.");
const encryptedCbc = wasm_aes_enc_cbc(plaintext, key, iv, "PKCS7");
const decryptedCbc = wasm_aes_dec_cbc(encryptedCbc, key, iv, "PKCS7");

Notes:

• plaintext should be a Uint8Array.
• key should be a Uint8Array of 16 bytes (AES-128), 24 bytes (AES-192), or 32 bytes (AES-256).
• iv for AES CBC should be a 16-byte Uint8Array.

In the example above a 16-byte key is used to demonstrate AES-128. Changing the key length to 24 or 32 bytes will use AES-192 or AES-256 respectively. The IV for AES CBC must always be 16 bytes regardless of the AES variant.

Test

To run tests, clone the project form github and build from source as described above. Navigate to the root folder and start a local server, e.g.:

python3 -m http.server

Open your browser and go to http://localhost:8000/test/index.html to see the test results.

Related Projects

soft-aes

The core Rust library on which this project relies is soft-aes.

Web UI

For a practical and user-friendly integration of this library in the browser visit AES-Wasm Tool.

License

Copyright David Schmid ([email protected])

Binaries are subject to the terms of the GPL-3.0 License - see the LICENSE file for details.