Merge pull request #62 from kevlened/rsa-fix

fix(RSASSA): change modulusLength and publicExponent calculation
anvilresearch · Feb 1, 2018 · 1566cdd · 1566cdd
2 parents 4aa22cc + 9f16126
commit 1566cdd
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Showing 2 changed files with 20 additions and 3 deletions.
diff --git a/src/algorithms/RSASSA-PKCS1-v1_5.js b/src/algorithms/RSASSA-PKCS1-v1_5.js
@@ -6,6 +6,7 @@ const crypto = require('crypto')
 const {spawnSync} = require('child_process')
 const keyto = require('@trust/keyto')
 const {TextEncoder, TextDecoder} = require('text-encoding')
+const base64url = require('base64url').default
 
 /**
  * Local dependencies
@@ -319,11 +320,11 @@ class RSASSA_PKCS1_v1_5 extends Algorithm {
     } else {
       throw new KeyFormatNotSupportedError(format)
     }
-    // 3-7. Setupp RSSASSA object
+    // 3-7. Setup RSSASSA object
     let alg = new RSASSA_PKCS1_v1_5({
       name: 'RSASSA-PKCS1-v1_5',
-      modulusLength: (new Buffer(jwk.n, 'base64').length / 2) * 8,
-      publicExponent: new Uint8Array([0x01, 0x00, 0x01]), // TODO use jwk.e
+      modulusLength: base64url.toBuffer(jwk.n).length * 8,
+      publicExponent: new Uint8Array(base64url.toBuffer(jwk.e)),
       hash: normalizedHash
     })
 

diff --git a/test/algorithms/RSASSA-PKCS1-v1_5_Spec.js b/test/algorithms/RSASSA-PKCS1-v1_5_Spec.js
@@ -661,6 +661,14 @@ const NotSupportedError = require('../../src/errors/NotSupportedError')
           key.algorithm.should.be.instanceof(RSASSA_PKCS1_v1_5)
         })
 
+        it('should define modulusLength', () => {
+          key.algorithm.modulusLength.should.eql(2048)
+        })
+
+        it('should define publicExponent', () => {
+          key.algorithm.publicExponent.should.eql(new Uint8Array([0x01, 0x00, 0x01]))
+        })
+
         it('should define extractable', () => {
           key.extractable.should.equal(false)
         })
@@ -690,6 +698,14 @@ const NotSupportedError = require('../../src/errors/NotSupportedError')
           key.algorithm.should.be.instanceof(RSASSA_PKCS1_v1_5)
         })
 
+        it('should define modulusLength', () => {
+          key.algorithm.modulusLength.should.eql(2048)
+        })
+
+        it('should define publicExponent', () => {
+          key.algorithm.publicExponent.should.eql(new Uint8Array([0x01, 0x00, 0x01]))
+        })
+
         it('should define extractable', () => {
           key.extractable.should.equal(true)
         })