feat: use forge to convert jwk2forge

src/keys/jwk2pem.js

@@ -0,0 +1,42 @@
+'use strict'
+
+const forge = {
+  util: require('node-forge/lib/util'),
+  pki: require('node-forge/lib/pki'),
+  jsbn: require('node-forge/lib/jsbn')
+}
+
+function base64urlToBigInteger (str) {
+  var bytes = forge.util.decode64(
+    (str + '==='.slice((str.length + 3) % 4))
+      .replace(/-/g, '+')
+      .replace(/_/g, '/'))
+  return new forge.jsbn.BigInteger(forge.util.bytesToHex(bytes), 16)
+}
+
+function convert (key, types) {
+  return types.map(t => base64urlToBigInteger(key[t]))
+}
+
+function jwk2priv (key) {
+  return forge.pki.setRsaPrivatKey(...convert(key, ['n', 'e', 'd', 'p', 'q', 'dP', 'dQ', 'qInv']))
+}
+
+function jwk2privPem (key) {
+  return forge.pki.privateKeyToPem(jwk2priv(key))
+}
+
+function jwk2pub (key) {
+  return forge.pki.setRsaPublicKey(...convert(key, ['n', 'e']))
+}
+
+function jwk2pubPem (key) {
+  return forge.pki.publicKeyToPem(jwk2pub(key))
+}
+
+module.exports = {
+  jwk2pub,
+  jwk2pubPem,
+  jwk2priv,
+  jwk2privPem
+}

src/keys/rsa-browser.js

@@ -127,19 +127,16 @@ RSA encryption/decryption for the browser with webcrypto workarround
 "bloody dark magic. webcrypto's why."
 
 Explanation:
-  - Convert JWK to PEM
+  - Convert JWK to nodeForge
-  - Load PEM with nodeForge
   - Convert msg buffer to nodeForge buffer: ByteBuffer is a "binary-string backed buffer", so let's make our buffer a binary string
   - Convert resulting nodeForge buffer to buffer: it returns a binary string, turn that into a uint8array(buffer)
 
 */
 
-const forge = require('node-forge')
+const { jwk2pub, jwk2priv } = require('./jwk2pem')
-const pki = forge.pki
+
-const jwkToPem = require('pem-jwk').jwk2pem
 function convertKey (key, pub, msg, handle) {
-  const pem = jwkToPem(key)
+  const fkey = pub ? jwk2pub(key) : jwk2priv(key)
-  const fkey = pki[pub ? 'publicKeyFromPem' : 'privateKeyFromPem'](pem)
   const fmsg = Buffer.from(msg).toString('binary')
   const fomsg = handle(fmsg, fkey)
   return Buffer.from(fomsg, 'binary')