Pure Javascript version of ripemd160 algorithm.

ripemd160.js

// Copyright (c) 2021 Pieter Wuille
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
// Revised and converted to Javascript by Christopher Scott.

function bytesToBigInt(bytes) {
  let num = 0n
  for (let i = bytes.length - 1; i >= 0; i--) {
    num = (num * 256n) + BigInt(bytes[i])
  }
  return BigInt(num)
}

function bigIntToBytes(num, size) {
  let bytes = []
  while (num > 0) {
    const byte = num & 0xffn
    bytes.push(byte)
    num = (num - byte) / 256n
  }
  bytes = bytes.map(n => Number(n))
  if (size) {
    const uint8 = new Uint8Array(size)
    uint8.set(bytes)
    bytes = [...uint8]
  }
  return bytes
}

function bytesToHex(bytes) {
  const hex = []
  for (let i = 0; i < bytes.length; i++) {
    hex.push(bytes[i].toString(16).padStart(2, '0'))
  }
  return hex.join('')
}

// Message schedule indexes for the left path.
const ML = [
  0n, 1n, 2n, 3n, 4n, 5n, 6n, 7n, 8n, 9n, 10n, 11n, 12n, 13n, 14n, 15n,
  7n, 4n, 13n, 1n, 10n, 6n, 15n, 3n, 12n, 0n, 9n, 5n, 2n, 14n, 11n, 8n,
  3n, 10n, 14n, 4n, 9n, 15n, 8n, 1n, 2n, 7n, 0n, 6n, 13n, 11n, 5n, 12n,
  1n, 9n, 11n, 10n, 0n, 8n, 12n, 4n, 13n, 3n, 7n, 15n, 14n, 5n, 6n, 2n,
  4n, 0n, 5n, 9n, 7n, 12n, 2n, 10n, 14n, 1n, 3n, 8n, 11n, 6n, 15n, 13n
]

// Message schedule indexes for the right path.
const MR = [
  5n, 14n, 7n, 0n, 9n, 2n, 11n, 4n, 13n, 6n, 15n, 8n, 1n, 10n, 3n, 12n,
  6n, 11n, 3n, 7n, 0n, 13n, 5n, 10n, 14n, 15n, 8n, 12n, 4n, 9n, 1n, 2n,
  15n, 5n, 1n, 3n, 7n, 14n, 6n, 9n, 11n, 8n, 12n, 2n, 10n, 0n, 4n, 13n,
  8n, 6n, 4n, 1n, 3n, 11n, 15n, 0n, 5n, 12n, 2n, 13n, 9n, 7n, 10n, 14n,
  12n, 15n, 10n, 4n, 1n, 5n, 8n, 7n, 6n, 2n, 13n, 14n, 0n, 3n, 9n, 11n
]

// Rotation counts for the left path.
const RL = [
  11n, 14n, 15n, 12n, 5n, 8n, 7n, 9n, 11n, 13n, 14n, 15n, 6n, 7n, 9n, 8n,
  7n, 6n, 8n, 13n, 11n, 9n, 7n, 15n, 7n, 12n, 15n, 9n, 11n, 7n, 13n, 12n,
  11n, 13n, 6n, 7n, 14n, 9n, 13n, 15n, 14n, 8n, 13n, 6n, 5n, 12n, 7n, 5n,
  11n, 12n, 14n, 15n, 14n, 15n, 9n, 8n, 9n, 14n, 5n, 6n, 8n, 6n, 5n, 12n,
  9n, 15n, 5n, 11n, 6n, 8n, 13n, 12n, 5n, 12n, 13n, 14n, 11n, 8n, 5n, 6n
]

// Rotation counts for the right path.
const RR = [
  8n, 9n, 9n, 11n, 13n, 15n, 15n, 5n, 7n, 7n, 8n, 11n, 14n, 14n, 12n, 6n,
  9n, 13n, 15n, 7n, 12n, 8n, 9n, 11n, 7n, 7n, 12n, 7n, 6n, 15n, 13n, 11n,
  9n, 7n, 15n, 11n, 8n, 6n, 6n, 14n, 12n, 13n, 5n, 14n, 13n, 13n, 7n, 5n,
  15n, 5n, 8n, 11n, 14n, 14n, 6n, 14n, 6n, 9n, 12n, 9n, 12n, 5n, 15n, 8n,
  8n, 5n, 12n, 9n, 12n, 5n, 14n, 6n, 8n, 13n, 6n, 5n, 15n, 13n, 11n, 11n
]

// K constants for the left path.
const KL = [0n, 0x5a827999n, 0x6ed9eba1n, 0x8f1bbcdcn, 0xa953fd4en]

// K constants for the right path.
const KR = [0x50a28be6n, 0x5c4dd124n, 0x6d703ef3n, 0x7a6d76e9n, 0n]

function fi(x, y, z, i) {
  // The f1, f2, f3, f4, and f5 functions from the specification.
  switch (true) {
    case (i === 0n):
      return x ^ y ^ z
    case (i === 1n):
      return (x & y) | (~x & z)
    case (i === 2n):
      return (x | ~y) ^ z
    case (i === 3n):
      return (x & z) | (y & ~z)
    case (i === 4n):
      return x ^ (y | ~z)
    default:
      throw new TypeError('Unknown I value: ' + i)
  }
}

function rol(x, i) {
  // Rotate the bottom 32 bits of x left by i bits.
  return ((x << i) | ((x & 0xffffffffn) >> (32n - i))) & 0xffffffffn
}

function compress(h0, h1, h2, h3, h4, block) {
  // Compress state (h0, h1, h2, h3, h4) with block.
  const x = []
  let rnd, elt, ert
  // Init left side of the array.
  let al = h0, bl = h1, cl = h2, dl = h3, el = h4
  // Init right side of the array.
  let ar = h0, br = h1, cr = h2, dr = h3, er = h4
  // Message variables.
  for (let i = 0; i < 16; i++) {
    const num = bytesToBigInt(block.slice(4 * i, 4 * (i + 1)))
    x.push(num)
  }
  // Iterate over the 80 rounds of the compression.
  for (let i = 0; i < 80; i++) {
    rnd = BigInt(i) >> 4n
    // Perform left side of the transformation.
    al = rol(al + fi(bl, cl, dl, rnd) + x[ML[i]] + KL[rnd], RL[i]) + el
    elt = el; el = dl; dl = rol(cl, 10n); cl = bl; bl = al; al = elt
    // Perform right side of the transformation.
    ar = rol(ar + fi(br, cr, dr, 4n - rnd) + x[MR[i]] + KR[rnd], RR[i]) + er
    ert = er; er = dr; dr = rol(cr, 10n); cr = br; br = ar; ar = ert
  }
  // Compose old state, left transform, and right transform into new state.
  return [h1 + cl + dr, h2 + dl + er, h3 + el + ar, h4 + al + br, h0 + bl + cr]
}

export function hash160(data) {
  // Compute the RIPEMD-160 hash of data.

  // Initialize state.
  let state = [0x67452301n, 0xefcdab89n, 0x98badcfen, 0x10325476n, 0xc3d2e1f0n]

  // Process full 64-byte blocks in the input.
  for (let b = 0; b < (data.length >> 6); b++) {
    state = compress(...state, data.slice(64 * b, 64 * (b + 1)))
  }
  // Construct final blocks (with padding and size).
  const zfill = new Array((119 - data.length) & 63).fill(0)
  const pad = [0x80n, ...zfill]
  const fin = [...data.slice(data.length & ~63), ...pad, ...bigIntToBytes(BigInt(8 * data.length), 8)]

  // Process final blocks.
  for (let i = 0; i < (fin.length >> 6); i++) {
    state = compress(...state, fin.slice(64 * i, 64 * (i + 1)))
  }

  // Produce output.
  const ret = []
  for (let i = 0; i < state.length; i++) {
    const num = state[i] & 0xffffffffn
    ret.push(...bigIntToBytes(num, 4))
  }

  return Uint8Array.from(ret)
}

export function test160() {
  const tests = [
    ['', '9c1185a5c5e9fc54612808977ee8f548b2258d31'],
    ['a', '0bdc9d2d256b3ee9daae347be6f4dc835a467ffe'],
    ['abc', '8eb208f7e05d987a9b044a8e98c6b087f15a0bfc'],
    ['message digest', '5d0689ef49d2fae572b881b123a85ffa21595f36'],
    ['abcdefghijklmnopqrstuvwxyz', 'f71c27109c692c1b56bbdceb5b9d2865b3708dbc'],
    ['abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq', '12a053384a9c0c88e405a06c27dcf49ada62eb2b'],
    ['ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789', 'b0e20b6e3116640286ed3a87a5713079b21f5189'],
    ['1234567890'.repeat(8), '9b752e45573d4b39f4dbd3323cab82bf63326bfb'],
    ['a'.repeat(1000000), '52783243c1697bdbe16d37f97f68f08325dc1528']
  ]

  for (const [preimg, target] of tests) {
    const ec = new TextEncoder()
    const res = bytesToHex(hash160(ec.encode(preimg)))
    if (res !== target) {
      throw new Error(`Test vector failed: ${res} !== ${target}`)
    }
  }
  return true
}