argon2

What is argon2?

The argon2 npm package is a library for hashing passwords using the Argon2 algorithm, which is a modern, secure, and memory-hard hashing algorithm. It is designed to be resistant to GPU cracking attacks and is considered one of the most secure password hashing algorithms available.

What are argon2's main functionalities?

Hashing a password

This feature allows you to hash a password using the Argon2 algorithm. The hash function takes a plain text password and returns a hashed version of it.

const argon2 = require('argon2');
(async () => {
  try {
    const hash = await argon2.hash('password');
    console.log(hash);
  } catch (err) {
    console.error(err);
  }
})();

Verifying a password

This feature allows you to verify a password against a previously hashed password. The verify function takes a hash and a plain text password and returns a boolean indicating whether the password matches the hash.

const argon2 = require('argon2');
(async () => {
  try {
    const hash = await argon2.hash('password');
    const isMatch = await argon2.verify(hash, 'password');
    console.log(isMatch); // true
  } catch (err) {
    console.error(err);
  }
})();

Configuring hashing options

This feature allows you to configure various options for the hashing process, such as the type of Argon2 algorithm to use (argon2d, argon2i, or argon2id), memory cost, time cost, and parallelism.

const argon2 = require('argon2');
(async () => {
  try {
    const hash = await argon2.hash('password', {
      type: argon2.argon2id,
      memoryCost: 2 ** 16,
      timeCost: 5,
      parallelism: 1
    });
    console.log(hash);
  } catch (err) {
    console.error(err);
  }
})();

Other packages similar to argon2

bcrypt

bcrypt is a popular password hashing library that uses the bcrypt algorithm. It is widely used and has been around for a long time. While bcrypt is still considered secure, Argon2 is generally considered to be more secure due to its resistance to GPU cracking attacks and its memory-hard properties.

pbkdf2

pbkdf2 is a password hashing library that uses the PBKDF2 algorithm. It is part of the cryptographic library in Node.js and is widely used. However, PBKDF2 is not memory-hard and is considered less secure than Argon2 for password hashing purposes.

scrypt

scrypt is a password hashing library that uses the scrypt algorithm. It is designed to be memory-hard and is considered secure. However, Argon2 is generally considered to be more secure and efficient than scrypt, and it has been recommended by various security experts and organizations.

README

node-argon2

Bindings to the reference Argon2 implementation.

Want to use it on command line? Instead check node-argon2-cli.

Before installing

You MUST have a node-gyp global install before proceeding with install, along with GCC >= 4.8 / Clang >= 3.3. On Windows, you must compile under Visual Studio 2015 or newer.

node-argon2 works only and is tested against Node >=4.0.0.

OSX

To install GCC >= 4.8 on OSX, use homebrew:

$ brew install gcc

Once you've got GCC installed and ready to run, you then need to install node-gyp, you must do this globally:

$ npm install -g node-gyp

Finally, once node-gyp is installed and ready to go, you can install this library, specifying the GCC or Clang binary to use:

$ CXX=g++-5 npm install argon2

NOTE: If your GCC or Clang binary is named something different than g++-5, you'll need to specify that in the command.

Usage

It's possible to hash a password using both Argon2i (default) and Argon2d, sync and async, and to verify if a password matches a hash, and also generate random cryptographically-safe salts. Salts must be at least 8-byte long buffers.

To hash a password:

const argon2 = require('argon2');
const salt = new Buffer('somesalt');

argon2.hash('password', salt).then(hash => {
  // ...
}).catch(err => {
  // ...
});

// OR

try {
  const hash = argon2.hashSync('password', salt);
} catch (err) {
  //...
}

// ES7

try {
  const hash = await argon2.hash('password', salt);
} catch (err) {
  //...
}

You can choose between Argon2i and Argon2d by passing an object as the third argument with the argon2d key set to whether or not you want Argon2d:

argon2.hash('password', salt, {
  argon2d: true
}.then(hash => {
  // ...
});

// OR

try {
  const hash = argon2.hashSync('password', salt, {
    argon2d: true
  });
} catch (err) {
  // ...
}

// ES7

try {
  const hash = await argon2.hash('password', salt, {
    argon2d: true
  });
} catch (err) {
  // ...
}

The argon2d option is flexible and accepts any truthy or falsy values.

You can provide your own salt as the second parameter. It is highly recommended to use the salt generating methods instead of a hardcoded, constant salt:

argon2.generateSalt().then(salt => {
  // ...
});

// OR

var salt = argon2.generateSaltSync();

// ES7

const salt = await argon2.generateSalt();

You can also pass a desired salt length as parameter. Although the default of 16 is enough and very safe, Argon2 will use all salt bytes.

argon2.generateSalt(32).then(salt => {
  // ...
});

// OR

var salt = argon2.generateSaltSync(32);

// ES7

const salt = await argon2.generateSalt(32);

Please keep in mind synchronous salt generation is blocking, since it waits for entropy when enough is not available, so please refrain from using sync version.

You can also modify time, memory and parallelism constraints passing the object as the third parameter, with keys timeCost, memoryCost and parallelism, respectively defaulted to 3, 12 (meaning 2^12 KB) and 1 (threads):

const options = {
  timeCost: 4, memoryCost: 13, parallelism: 2, argon2d: true
};

argon2.generateSalt().then(salt => {
  argon2.hash('password', salt, options).then(hash => {
    // ...
  });
});

// OR

var hash = argon2.hashSync('password', argon2.generateSaltSync(), options);

// ES7

var hash = await argon2.hash('password', await argon2.generateSalt(), options);

The default parameters for Argon2 can be accessed with defaults:

console.log(argon2.defaults);
// => { timeCost: 3, memoryCost: 12, parallelism: 1, argon2d: false }

To verify a password:

argon2.verify('<big long hash>', 'password').then(() => {
  // password match
}).catch(() => {
  // password did not match
});

// OR

if (argon2.verifySync('<big long hash>', 'password')) {
  // password match
} else {
  // password did not match
}

// ES7

try {
  await argon2.verify('<big long hash>', 'password');
  // password match
} catch (err) {
  // password did not match
}

First parameter must have been generated by an Argon2 encoded hashing method, not raw.

License

Work licensed under the MIT License. Please check [P-H-C/phc-winner-argon2] (https://github.com/P-H-C/phc-winner-argon2) for license over Argon2 and the reference implementation.