TypeScript HBEDF

TypeScript HBEDF provides functionality for generating deterministic pseudorandom sequences of bytes from human-derived values. A derived seed can be generated from an array of biographic material, and a secret, across four phases: Key, Extract, Shuffle, an Expand. Natively in TypeScript, with ESM and CommonJS compatibility. To get started, install the library:

# Deno
deno add jsr:@iacobus/hbedf

# Node.js
npm install @iacobus/hbedf

This is a reference implementation of the Human-Based Entropy Derivation Function (HBEDF), from the specification titled "Deterministic Method of Entropy Derivation from Human Identity and Secrets". The cryptographic keys used across internal derivation phases are Hierarchical Deterministic Symmetric Keys.

Derive a Seed

TypeScript/ESM import:

import { hbedf } from "@iacobus/hbedf";

CommonJS require:

const { hbedf } = require("@iacobus/hbedf");

A derived seed can be generated using the hbedf function. A synchronous version of this function also exists, as the hbedfSync function. For demonstration purposes, the asynchronous version will be used.

HBEDF Function

The HBEDF function has four input parameters:

async function hbedf(h, ibm, secret, opts) {};

Where:

• h is a hash function (e.g. sha256, sha512).
• ibm is an array of initial biographic information (e.g. name, date of birth, document number).
• secret is the secret information (e.g. PIN, passphrase) used to generate the key used across internal derivation phases.
• opts are the options for configuring seed derivation.
  • path is the derivation path used to generate the internal HD key.
  • schema (optional) is the derivation path schema (uses a default schema when undefined).
  • c is an iterations count, for the number of HMAC iterations applied to ibm for strengthening.
  • mem is the target memory cost in MiB applied cumulatively across Scrypt invocations during array shuffling.
  • dsLen (optional) is the desired byte length of the derived seed (default 32).

The h parameter is expected as any compatible hash function (noble-hashes CHash). The ibm parameter is expected as an array of Uint8Arrays. The secret parameter is expected as a Uint8Array. The opts parameter is expected as an HbedfOpts object. The HBEDF function is asynchronous, and returns a Promise that resolves to a Uint8Array. The hbedfSync function is synchronous, and returns a Uint8Array.

HbedfOpts Type

The HbedfOpts type is an object containing the derivation path, optional derivation path schema, iterations count, target memory cost, and optional output length.

type HbedfOpts = {
	path: string;
	schema?: string;
	c: number;
	mem: number;
	dsLen?: number;
};

Example Use

import { hbedf, type HbedfOpts } from "@iacobus/hbedf";
import { sha256 } from "@noble/hashes/sha2";
import { hexToBytes, utf8ToBytes } from "@noble/hashes/utils";

// Use sha256
const h = sha256;

// Encode the biographic material
const bio = ["MUSTERMANN", "ERIKA", "L01X00T47", "12081983"];
const ibm: Uint8Array[] = bio.map((b) => utf8ToBytes(b));

// Encode a secret from a hex string
const secret = hexToBytes("54686520696D6D6F7274616C20736E61696C20697320626568696E6420796F75");

// Generate a derived seed
const opts: HbedfOpts = { path: "m/42/0/1/0", c: 10000, mem: 128, dsLen: 64 };
const ds = await hbedf(h, ibm, secret, opts);

/*
Uint8Array(64) [
  198,  79, 202,  89,  94,  30, 208,  96,  11,  39, 108,
  154, 173, 127,  12,  13, 150, 116, 218, 252, 230, 100,
   33, 207, 134, 245, 133, 133,  83,  28, 105, 188, 223,
   20, 139, 117,  61,   9, 208, 229, 116,  94,  37, 112,
  179, 201,  29, 239, 140, 231, 108, 210, 254,   6, 195,
  182, 115, 138, 176, 165, 222, 155, 192,   9
]
*/