ssb-keyring/util.js

A persistence store for encryption keys for scuttlebutt. It's purpose is to make easy to answer box2 encryption/ decryption questions.

const bfe = require('ssb-bfe')
const { isMsg, isCloakedMsgId } = require('ssb-ref')
const { isMessageSSBURI, isIdentityGroupSSBURI } = require('ssb-uri2')

function toBuffer (thing, length) {
  const buf = Buffer.isBuffer(thing)
    ? thing
    : Buffer.from(thing, 'base64')

  if (length && buf.length !== length) {
    throw new Error(`expected buffer of length ${length} bytes, got ${buf.length}`)
  }

  return buf
}

const POBOX_TF = bfe.toTF('identity', 'po-box')
function isPOBoxId (id) {
  try {
    const bfeId = bfe.encode(id)

    return (
      bfeId.length === 34 && // 2 + crypto_scalarmult_SCALARBYTES = 34 bytes
      bfeId.slice(0, 2).equals(POBOX_TF)
    )
  } catch (err) {
    return false
  }
}

function isFeedId (str) {
  // TODO make this stronger?
  return str.match(/^(@|ssb:feed)/)
}

function isMsgId (id) {
  return isMsg(id) || isMessageSSBURI(id)
}

function isGroupId (id) {
  return isCloakedMsgId(id) || isIdentityGroupSSBURI(id)
}

module.exports = {
  toBuffer,
  isPOBoxId,
  isPOBox: isPOBoxId,
  isMsgId,
  isMsg: isMsgId,
  isGroupId,
  isGroup: isGroupId,
  isFeedId,
  isFeed: isFeedId,
  isBuffer: Buffer.isBuffer,
  isString: (str) => typeof str === 'string',
  isObject (obj) {
    if (obj === null) return false
    if (Buffer.isBuffer(obj)) return false
    return typeof obj === 'object'
  },
  isSameKey (A, B) {
    return toBuffer(A).equals(toBuffer(B))
  }
  // signKeysToEncryptionKeys
}