Fixed RSASSA-PKCS1-v1_5.js to use NodeRSA if openssl is not installed…

package.json

@@ -30,7 +30,8 @@
     "base64url": "^3.0.0",
     "elliptic": "^6.4.0",
     "node-rsa": "^0.4.0",
-    "text-encoding": "^0.6.1"
+    "text-encoding": "^0.6.1",
+    "node-forge": "^0.8.0"
   },
   "devDependencies": {
     "chai": "^3.5.0",

src/algorithms/RSASSA-PKCS1-v1_5.js

@@ -7,6 +7,7 @@ const {spawnSync} = require('child_process')
 const keyto = require('@trust/keyto')
 const {TextEncoder, TextDecoder} = require('text-encoding')
 const base64url = require('base64url').default
+const pki = require('node-forge').pki
 
 /**
  * Local dependencies
@@ -176,11 +177,23 @@ class RSASSA_PKCS1_v1_5 extends Algorithm {
       // - fallback on node-rsa if OpenSSL is not available on the system
       let privateKey = spawnSync('openssl', ['genrsa', modulusLength || 4096]).stdout
       let publicKey = spawnSync('openssl', ['rsa', '-pubout'], { input: privateKey }).stdout
-      try {
-        keypair.privateKey = privateKey.toString('ascii')
-        keypair.publicKey = publicKey.toString('ascii')
-      } catch (error){
-        throw new OperationError(error.message)
+
+      if(privateKey && publicKey) {
+        try {
+          keypair.privateKey = privateKey.toString('ascii')
+          keypair.publicKey = publicKey.toString('ascii')
+        } catch (error){
+          throw new OperationError(error.message)
+        }
+      } else {
+        // - what is this bit option, where do we get the value from in this api?
+        let {modulusLength,publicExponent} = params
+        let key = new RSA({b:(modulusLength || 4096)})        
+        privateKey = pki.privateKeyFromPem(key.exportKey())
+        publicKey = pki.setRsaPublicKey(privateKey.n, privateKey.e)    
+
+        keypair.privateKey = pki.privateKeyToPem(privateKey)
+        keypair.publicKey = pki.publicKeyToPem(publicKey)
       }
     // 3. Throw operation error if anything fails
     } catch (error) {