Kotlin Multiplatform Crypto Library

Kotlin Multiplatform Crypto is a library for various cryptographic applications.

This is an extremely early release, currently only consisting of Blake2b and SHA256 and 512.

Notes & Roadmap

The API will move fast and break often until v1.0

Make SHA hashes "updateable" like Blake2b

After that tenative plan is to add 25519 curve based signing and key exchange next.

Should I use this in production?

No, it's untested and unproven.

Supported

Hashing functions

• Blake2b
• SHA512
• SHA256

More to come.

Integration

Gradle

implementation("com.ionspin.kotlin:crypto:0.0.1")

Snapshot builds

repositories {
    maven {
        url = uri("https://oss.sonatype.org/content/repositories/snapshots")
    }
}
implementation("com.ionspin.kotlin:crypto:0.0.1-SNAPSHOT")

Usage

Blake2b

You can use Blake 2b in two modes

Using a Blake2b object

You need to deliver the complete data that is to be hashed in one go

val input = "abc"
val result = Blake2b.digest(input)

Result is returned as a Array<Byte>

Using a Blake2b instance

You can create an instance and feed the data by using update(input : Array<Byte>) call. Once all data is supplied, you should call digest() or digestString() convinence method that converts the Array<Byte> into hexadecimal string.

If you want to use Blake2b with a key, you should supply it when creating the Blake2b instance.

val test = "abc"
val key = "key"
val blake2b = Blake2b(key)
blake2b.update(test)
val result = blake2b.digest()

After digest is called, the instance is reset and can be reused (Keep in mind key stays the same for the particular instance).

SHA2 (SHA256 and SHA512)

You need to deliver the complete data that is to be hashed in one go. You can either provide the Array<Byte> as input or String. Result is always returned as Array<Byte> (At least in verision 0.0.1)

val input = "abc"
val result = Sha256.digest(input)

val input ="abc"
val result = Sha512.digest(message = input.encodeToByteArray().map { it.toUByte() }.toTypedArray())

Result is returned as a Array<Byte>