emstlk / nacl4s

Scala implementation of Networking and Cryptography (NaCl) library

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NaCl4s - NaCl library for Scala

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NaCl represents modern and powerful crypto library. That implementation was inspired by projects libsodium and kalium

Currently it has minimal functionality (box, secret box and signatures) based on algorithms:

  • Salsa20
  • HSalsa20
  • XSalsa20
  • Poly1305
  • Curve25519
  • Sha512
  • Ed25519


NaCl4s is published at Maven Central. Simply use the following sbt snippet:

libraryDependencies ++= Seq(
  "com.github.emstlk" %% "nacl4s" % "1.0.0"

Using the library

Public-key authenticated encryption

This approach allows you to encrypt a secret message for your friend, using friend's public key. You can read more details here

import com.emstlk.nacl4s._

val myKeys = KeyPair()
val friendKeys = KeyPair()

val myBox = Box(friendKeys.publicKey, myKeys.privateKey)
val nonce = Box.randomNonce()
val encrypted = myBox.encrypt(nonce, "See you tomorrow at my favourite place 😎️".asBytes)

val friendBox = Box(myKeys.publicKey, friendKeys.privateKey)
val message = friendBox.decrypt(nonce, encrypted).asString

Secret-key authenticated encryption

In that case a single key is used to encrypt and decrypt messages. More details here

import com.emstlk.nacl4s._

val myBox = SecretBox.withRandomKey()
val key = myBox.key
val nonce = SecretBox.randomNonce()
val encrypted = myBox.encrypt(nonce, "Just another message".asBytes)

val friendBox = SecretBox(key)
val message = friendBox.decrypt(nonce, encrypted).asString

Public-key signatures

You can generate a key pair which allow you sign any message and anybody can verify it with your public key. More details here

import com.emstlk.nacl4s._

val keys = SigningKeyPair()
val message = "The new one message".asBytes
val signature = SigningKey(keys.privateKey).sign(message)

VerifyKey(keys.publicKey).verify(message, signature)


NaCl4s is still a work in progress