Merge pull request #26 from microsoft/copilot/fix-bn-254-padding-issue

Refactor EC key padding length lookup into shared cryptoECC helper; add BN-254 support

Author: ljoy913

src/cryptoECC.js

@@ -2002,6 +2002,19 @@ function MsrcryptoECC() {
 
     var curvesInternal = {};
 
+    var curveElementLengths = {
+        "P-256": 32,
+        "P-384": 48,
+        "P-521": 66,
+        "BN-254": 32,
+        "NUMSP256D1": 32,
+        "NUMSP256T1": 32,
+        "NUMSP384D1": 48,
+        "NUMSP384T1": 48,
+        "NUMSP512D1": 64,
+        "NUMSP512T1": 64
+    };
+
     var createCurve = function(curveName) {
 
         var curveData = curvesInternal[curveName.toUpperCase()];
@@ -2028,8 +2041,17 @@ function MsrcryptoECC() {
         return opp.validatePoint(point);
     };
 
+    var curveElementLength = function(curveName) {
+        if (!curveName) {
+            return undefined;
+        }
+
+        return curveElementLengths[curveName.toUpperCase()];
+    };
+
     return {
         createCurve: createCurve,
+        curveElementLength: curveElementLength,
         curves: curvesInternal,
         sec1EncodingFp: sec1EncodingFp,
         validatePoint: validateEccPoint,

src/ecdh.js

@@ -156,12 +156,7 @@ if ( typeof operations !== "undefined" ) {
 
         // Pad each value to the curve's fixed element length so leading zeros
         // are preserved (matches Chrome / Chromium-based Edge behavior).
-        var partLen = {
-            "P-256": 32, "P-384": 48, "P-521": 66,
-            "NUMSP256D1": 32, "NUMSP256T1": 32,
-            "NUMSP384D1": 48, "NUMSP384T1": 48,
-            "NUMSP512D1": 64, "NUMSP512T1": 64
-        }[p.algorithm.namedCurve];
+        var partLen = cryptoECC.curveElementLength(p.algorithm.namedCurve);
         var pad = msrcryptoUtilities.padFront;
         keyPairData.publicKey.x = pad(keyPairData.publicKey.x, 0, partLen);
         keyPairData.publicKey.y = pad(keyPairData.publicKey.y, 0, partLen);
@@ -250,12 +245,7 @@ if ( typeof operations !== "undefined" ) {
 
                 // Accept keys with or without trimmed leading zeros and pad each
                 // value to the curve's fixed element length (Chrome/Chromium behavior).
-                var partLen = {
-                    "P-256": 32, "P-384": 48, "P-521": 66,
-                    "NUMSP256D1": 32, "NUMSP256T1": 32,
-                    "NUMSP384D1": 48, "NUMSP384T1": 48,
-                    "NUMSP512D1": 64, "NUMSP512T1": 64
-                }[p.algorithm.namedCurve];
+                var partLen = cryptoECC.curveElementLength(p.algorithm.namedCurve);
                 if ( keyObject.x ) { keyObject.x = msrcryptoUtilities.padFront(keyObject.x, 0, partLen); }
                 if ( keyObject.y ) { keyObject.y = msrcryptoUtilities.padFront(keyObject.y, 0, partLen); }
                 if ( keyObject.d ) { keyObject.d = msrcryptoUtilities.padFront(keyObject.d, 0, partLen); }

src/ecdsa.js

@@ -207,12 +207,7 @@ if (typeof operations !== "undefined") {
 
         // Pad each value to the curve's fixed element length so leading zeros
         // are preserved (matches Chrome / Chromium-based Edge behavior).
-        var partLen = {
-            "P-256": 32, "P-384": 48, "P-521": 66,
-            "NUMSP256D1": 32, "NUMSP256T1": 32,
-            "NUMSP384D1": 48, "NUMSP384T1": 48,
-            "NUMSP512D1": 64, "NUMSP512T1": 64
-        }[p.algorithm.namedCurve];
+        var partLen = cryptoECC.curveElementLength(p.algorithm.namedCurve);
 
         function padToCurveLength( array ) {
             return msrcryptoUtilities.padFront(array, 0, partLen);
@@ -307,12 +302,7 @@ if (typeof operations !== "undefined") {
 
             // Accept keys with or without trimmed leading zeros and pad each
             // value to the curve's fixed element length (Chrome/Chromium behavior).
-            var partLen = {
-                "P-256": 32, "P-384": 48, "P-521": 66,
-                "NUMSP256D1": 32, "NUMSP256T1": 32,
-                "NUMSP384D1": 48, "NUMSP384T1": 48,
-                "NUMSP512D1": 64, "NUMSP512T1": 64
-            }[p.algorithm.namedCurve];
+            var partLen = cryptoECC.curveElementLength(p.algorithm.namedCurve);
             if ( keyObject.x ) { keyObject.x = msrcryptoUtilities.padFront(keyObject.x, 0, partLen); }
             if ( keyObject.y ) { keyObject.y = msrcryptoUtilities.padFront(keyObject.y, 0, partLen); }
             if ( keyObject.d ) { keyObject.d = msrcryptoUtilities.padFront(keyObject.d, 0, partLen); }

test/Test.Ecdh.js

@@ -125,6 +125,10 @@ function ecdhTests() {
         ts.keyGeneratePairTest(ecdhKeyAlg("P-521"), ["deriveKey", "deriveBits"], inspectEcdhKey, context(iterations, assert));
     });
 
+    QUnit.test(label + " generateKeyTest BN-254", function(assert) {
+        ts.keyGeneratePairTest(ecdhKeyAlg("BN-254"), ["deriveKey", "deriveBits"], inspectEcdhKey, context(iterations, assert));
+    });
+
     QUnit.test(label + " ts.deriveKeyTest P-256 --> Aes-Cbc-256 ", function(assert) {
         ts.deriveKeyTest(ecdh.p256.DeriveKey, undefined, context(iterations, assert));
     });
@@ -222,17 +226,9 @@ function ecdhTests() {
     });
 }
 
-var ecdhKeyLengths = {
-    "P-256": 32,
-    "P-384": 48,
-    "P-521": 66,
-    "NUMSP256D1": 32,
-    "NUMSP256T1": 32,
-    "NUMSP384D1": 48,
-    "NUMSP384T1": 48,
-    "NUMSP512D1": 64,
-    "NUMSP512T1": 64
-};
+function ecdhCurveElementLength(namedCurve) {
+    return cryptoECC.curveElementLength(namedCurve);
+}
 
 function ecdhKeyAlg(namedCurve) {
     return {
@@ -245,7 +241,7 @@ var inspectEcdhKey = {
     public: function(keyObj, algorithm, usages, reason) {
 
         var fail = [];
-        var expLenMax = ecdhKeyLengths[algorithm.namedCurve];
+        var expLenMax = ecdhCurveElementLength(algorithm.namedCurve);
         var expLenMin = expLenMax;
 
         // has crv property equal to "P-521"
@@ -304,7 +300,7 @@ var inspectEcdhKey = {
         //     }
         // }
 
-        var expLenMax = ecdhKeyLengths[algorithm.namedCurve];
+        var expLenMax = ecdhCurveElementLength(algorithm.namedCurve);
         var expLenMin = expLenMax;
 
         this.public(keyObj, algorithm, usages, reason);

test/Test.Ecdsa.js

@@ -248,6 +248,10 @@ function ecdsaTests() {
         ts.keyGeneratePairTest( ecdsaKeyAlg( "P-521" ), [VERIFY, SIGN], inspectEcdsaKey, context( iterations, assert ) );
     } );
 
+    QUnit.test(label + " generateKeyTest BN-254", function(assert) {
+        ts.keyGeneratePairTest(ecdsaKeyAlg("BN-254"), [VERIFY, SIGN], inspectEcdsaKey, context(iterations, assert));
+    });
+
     QUnit.test(label + " generateKeyTest NUMSP256D1", function(assert) {
         ts.keyGeneratePairTest(ecdsaKeyAlg("NUMSP256D1"), [VERIFY, SIGN], inspectEcdsaKey, context(iterations, assert));
     });
@@ -419,17 +423,9 @@ function ecdsaTests() {
     });
 }
 
-var ecdsaKeyLengths = {
-    "P-256": 32,
-    "P-384": 48,
-    "P-521": 66,
-    "NUMSP256D1": 32,
-    "NUMSP256T1": 32,
-    "NUMSP384D1": 48,
-    "NUMSP384T1": 48,
-    "NUMSP512D1": 64,
-    "NUMSP512T1": 64
-};
+function ecdsaCurveElementLength(namedCurve) {
+    return cryptoECC.curveElementLength(namedCurve);
+}
 
 function ecdsaKeyAlg(curve) {
     return {
@@ -450,7 +446,7 @@ var inspectEcdsaKey = {
 
         var fail = [];
 
-        var expLenMax = ecdsaKeyLengths[algorithm.namedCurve];
+        var expLenMax = ecdsaCurveElementLength(algorithm.namedCurve);
         var expLenMin = expLenMax;
 
         // has crv property equal to "P-521"
@@ -493,7 +489,7 @@ var inspectEcdsaKey = {
     },
     private: function(keyObj, algorithm, usages, reason) {
 
-        var expLenMax = ecdsaKeyLengths[algorithm.namedCurve];
+        var expLenMax = ecdsaCurveElementLength(algorithm.namedCurve);
         var expLenMin = expLenMax;
 
         this.public(keyObj, algorithm, usages, reason);