Base58 & KDF

Base58 Encoding

Kodium provides efficient Base58 and Base58Check extensions for ByteArray and String. Base58 is superior to Base64 for many crypto use cases as it eliminates ambiguous characters (0, O, I, l) and is more compact than hexadecimal representation.

val data = "Kodium Pure Kotlin".encodeToByteArray()

// Standard Base58
val b58 = data.encodeToBase58String()
val decoded = b58.decodeBase58()

// Base58 with Checksum (Standard in Bitcoin and many crypto networks)
// The checksum helps prevent accidental typos when users manually enter or copy strings.
val b58Check = data.encodeToBase58WithChecksum()
val decodedCheck = b58Check.decodeBase58WithChecksum()

Password-Based Key Derivation (PBKDF2)

Deriving strong cryptographic keys from user passwords is a common requirement. Kodium provides a built-in Key Derivation Function (KDF) using PBKDF2 with HMAC-SHA256.

val password = "UserPassword123".encodeToByteArray()
val salt = "RandomSalt".encodeToByteArray() // Should be securely random and at least 16 bytes

// Derive a 32-byte key (suitable for SecretBox)
val derivedKey = KDF.deriveKey(
    password = password,
    salt = salt,
    iterations = 100_000, // Higher iterations = slower derivation, harder to brute force
    keyLengthBytes = 32
)