Crypto

The Helios Crypto class contains a collection of cryptography primitives:

• Mulberry32: pseudo random number generator
• Base32 encoding and decoding
• Bech32 encoding, checking, and decoding
• Sha2 256, Sha2 512, Sha3 and Blake2b hashing
• Ed25519 pubkey generation, signing, and signature verification

These functions have been implemented as part of the Helios library in order to avoid external dependencies (there still isn't a standardized Javascript Crypto API that provides all the needed functionality).

Random number generators

mulberry32

A simple pseudo number generator for use in tests that requires some randomness but need to be deterministic (i.e. each test run gives the same result).

helios.Crypto.mulberry32(seed: number): (() => number)

The returned function returns a new random number between 0 and 1 upon each call.

rand

Alias for mulberry32.

helios.Crypto.rand(seed: number): (() => number)

Base32

Needed by Bech32.

encodeBase32

helios.Crypto.encodeBase32(
    bytes: number[],
    alphabet: string = DEFAULT_BASE32_ALPHABET
): string

decodeBase32

helios.Crypto.decodeBase32(
    encoded: string,
    alphabet: string = DEFAULT_BASE32_ALPHABET
): number[]

DEFAULT_BASE32_ALPHABET

helios.Crypto.DEFAULT_BASE32_ALPHABET: "abcdefghijklmnopqrstuvwxyz234567"

BECH32_BASE32_ALPHABET

helios.Crypto.DEFAULT_BASE32_ALPHABET: "qpzry9x8gf2tvdw0s3jn54khce6mua7l"

Bech32

Address encoding scheme used by Cardano. Includes a checksum.

encodeBech32

The human readable part is "addr" or "addr_test" for Cardano addresses.

helios.Crypto.encodeBech32(
    hrp: string, // typically "addr" or "addr_test"
    data: number[]
): string

decodeBech32

Throws an error if the checksum is invalid. Returns both the human readable part and the contained data bytes.

helios.Crypto.decodeBech32(
    encoded: string
): [string, number[]]

verifyBech32

Returns false if the bech32 checksum is incorrect.

helios.Crypto.verifyBech32(encoded: string): boolean

Hashing

sha2_256

The returned hash is 32 bytes long.

helios.Crypto.sha2_256(bytes: number[]): number[]

sha2_512

The returned hash is 64 bytes long.

helios.Crypto.sha2_512(bytes: number[]): number[]

sha3

The returned hash is 32 bytes long.

helios.Crypto.sha3(bytes: number[]): number[]

blake2b

The returned hash can be up to 64 bytes long (length can be chosen by the caller).

helios.Crypto.blake2b(
    bytes: number[],
    digestSize: number = 32
): number[]

Ed25519

The elliptic curve signature algorithm used by Cardano wallets. The current implementation is simple but slow.

derivePublicKey

Derive a public key from a private key. The private key can be any number of bytes (it's hashed internally). The returned public key is 32 bytes long.

helios.Crypto.Ed25519.derivePublicKey(privateKey: number[]): number[]

sign

Creates a 64 byte signature.

helios.Crypto.Ed25519.sign(
    message: number[],
    privateKey: number[]
): number[]

verify

Returns true if the signature is correct.

helios.Crypto.Ed25519.verify(
    signature: number[],
    message: number[],
    publicKey: number[]
): boolean