@dsnp/hash-util

Overview

This package is a TypeScript implementation of hash-related utilities to support DSNP applications and services.

Background

DSNP anchors content to announcements via a URL and hashes. This ensures integrity of resources and also provides for relocatable content, as hashes can be generated and verified regardless of location.

This library provides a simple implementation that checks whether a data "file" matches at least one of the hash values provided.

Dependencies

This library uses hash-wasm, which has fast WASM implementations of hash algorithms and should work in both server-side and browser environments.

Usage

Given a Uint8Array and an array of strings representing DSNP hashes, use the following function to verify if there is a matching hash.

import { compareBinaryToMultibaseHashes } from "@dsnp/hash-util";

const result = await compareBinaryToMultibaseHashes(binaryU8A, hashes);

Compatibility

The library will verify the following types of hashes:

• multihash values
  • base32 multibase encoding (leading 'b' character)
  • sha2-256 or blake3 hash (leading 0x12 or 0x1e byte)
  • 256-bit hash length (0x20 after hash indicator)

Limitations

All comparisons are done in-memory, meaning that there is no attempt to limit the size of the byte array or memory requirements. Callers should therefore perform their own sanity checks.

Development

npm i
npm run build
npm run test

Please use the github issues area to report bugs or suggest enhancements. Pull requests are gratefully welcomed.