fix: maps an IPFS hash name to its forge equivalent

Fixes #12

src/keychain.js

@@ -19,13 +19,26 @@ const NIST = {
  minIterationCount: 1000
 }
 
+/**
+ * Maps an IPFS hash name to its forge equivalent.
+ *
+ * See https:/multiformats/multihash/blob/master/hashtable.csv
+ *
+ * @private
+ */
+const hashName2Forge = {
+ 'sha1': 'sha1',
+ 'sha2-256': 'sha256',
+ 'sha2-512': 'sha512',
+
+}
 const defaultOptions = {
  // See https://cryptosense.com/parametesr-choice-for-pbkdf2/
  dek: {
  keyLength: 512 / 8,
  iterationCount: 10000,
  salt: 'you should override this value with a crypto secure random number',
- hash: 'sha512'
+ hash: 'sha2-512'
  }
 }
 
@@ -120,13 +133,18 @@ class Keychain {
  }
  this.dek = opts.dek
 
+ // Get the hashing alogorithm
+ const hashAlgorithm = hashName2Forge[opts.dek.hash]
+ if (!hashAlgorithm)
+ throw new Error(`dek.hash '${opts.dek.hash}' is unknown or not supported`)
+
  // Create the derived encrypting key
  let dek = forge.pkcs5.pbkdf2(
  opts.passPhrase,
  opts.dek.salt,
  opts.dek.iterationCount,
  opts.dek.keyLength,
- opts.dek.hash)
+ hashAlgorithm)
  dek = forge.util.bytesToHex(dek)
  Object.defineProperty(this, '_', { value: () => dek })
 

test/keychain.spec.js

@@ -41,6 +41,12 @@ module.exports = (datastore1, datastore2) => {
  expect(Keychain.options).to.exist()
  })
 
+ it('needs a supported hashing alorithm', () => {
+ const ok = new Keychain(datastore2, { passPhrase: passPhrase, dek: { hash: 'sha2-256' } })
+ expect(ok).to.exist()
+ expect(() => new Keychain(datastore2, { passPhrase: passPhrase, dek: { hash: 'my-hash' } })).to.throw()
+ })
+
  describe('key name', () => {
  it('is a valid filename and non-ASCII', () => {
  ks.removeKey('../../nasty', (err) => {