Function deriveSecretKeyTreeChild

packages/happy-agent/src/encryption.ts:57–64

(chainCode: Uint8Array, index: string)

}

export function deriveSecretKeyTreeChild(chainCode: Uint8Array, index: string): KeyTreeState {
    const data = new Uint8Array([0x00, ...new TextEncoder().encode(index)]);
    const I = hmac_sha512(chainCode, data);
    return {
        key: I.slice(0, 32),
        chainCode: I.slice(32),
    };
}

export function deriveKey(master: Uint8Array, usage: string, path: string[]): Uint8Array {
    let state = deriveSecretKeyTreeRoot(master, usage);