sec: use a hashtable for lookup

src/sec.js

@@ -193,17 +193,17 @@ function secp256r1() {
     return new X9ECParameters(curve, G, n, h);
 }
 
-// TODO: make this into a proper hashtable
 function getSECCurveByName(name) {
-    if(name == "secp128r1") return secp128r1();
-    if(name == "secp160k1") return secp160k1();
-    if(name == "secp160r1") return secp160r1();
-    if(name == "secp192k1") return secp192k1();
-    if(name == "secp192r1") return secp192r1();
-    if(name == "secp224r1") return secp224r1();
-    if(name == "secp256k1") return secp256k1();
-    if(name == "secp256r1") return secp256r1();
-    return null;
+    return ({
+      "secp128r1": secp128r1,
+      "secp160k1": secp160k1,
+      "secp160r1": secp160r1,
+      "secp192k1": secp192k1,
+      "secp192r1": secp192r1,
+      "secp224r1": secp224r1,
+      "secp256k1": secp256k1,
+      "secp256r1": secp256r1
+    }[name])()
 }
 
-module.exports = getSECCurveByName;
+module.exports = getSECCurveByName