From 2635e8d3c997b8792a2f94c7a8d5dd76b0985e6d Mon Sep 17 00:00:00 2001
From: Jordi <ledfusion@users.noreply.github.com>
Date: Tue, 12 Feb 2019 12:21:44 +0100
Subject: [PATCH] Make code independent of NodeJS core modules

---
 calcpedersenbases/calcpedersenbases.js |  9 ++++++---
 src/eddsa.js                           |  6 ------
 src/evmasm.js                          | 20 ++++++++++++--------
 src/pedersenHash.js                    |  5 +++--
 test/eddsa.js                          |  3 ++-
 5 files changed, 23 insertions(+), 20 deletions(-)

diff --git a/calcpedersenbases/calcpedersenbases.js b/calcpedersenbases/calcpedersenbases.js
index c7ae74c..b24842a 100644
--- a/calcpedersenbases/calcpedersenbases.js
+++ b/calcpedersenbases/calcpedersenbases.js
@@ -1,14 +1,15 @@
 const bn128 = require("snarkjs").bn128;
 const bigInt = require("snarkjs").bigInt;
 const createBlakeHash = require("blake-hash");
-const assert = require("assert");
 const babyJub = require("../src/babyjub");
 
 function getPoint(S) {
     const F = bn128.Fr;
     const h = createBlakeHash("blake256").update(S).digest();
 
-    assert(h.length == 32);
+    if (h.length != 32) {
+        throw new Error("Invalid length")
+    }
 
     let sign = false;
     if (h[31] & 0x80) {
@@ -52,7 +53,9 @@ function generatePoint(S) {
         p = getPoint(S+"_"+sidx);
         idx++;
     }
-    assert(babyJub.inCurve(p), "Point not in curve");
+    if (!babyJub.inCurve(p)){
+        throw new Error("Point not in curve");
+    }
     return p;
 }
 
diff --git a/src/eddsa.js b/src/eddsa.js
index eb869c3..4991881 100644
--- a/src/eddsa.js
+++ b/src/eddsa.js
@@ -3,9 +3,7 @@ const bigInt = require("snarkjs").bigInt;
 const babyJub = require("./babyjub");
 const pedersenHash = require("./pedersenHash").hash;
 const mimc7 = require("./mimc7");
-const crypto = require("crypto");
     
-exports.cratePrvKey = cratePrvKey;
 exports.prv2pub= prv2pub;
 exports.sign = sign;
 exports.signMiMC = signMiMC;
@@ -16,10 +14,6 @@ exports.unpackSignature = unpackSignature;
 exports.pruneBuffer = pruneBuffer;
 
 
-function cratePrvKey() {
-    return crypto.randomBytes(32);
-}
-
 function pruneBuffer(_buff) {
     const buff = Buffer.from(_buff);
     buff[0] = buff[0] & 0xF8;
diff --git a/src/evmasm.js b/src/evmasm.js
index 351201b..ad4170c 100644
--- a/src/evmasm.js
+++ b/src/evmasm.js
@@ -4,7 +4,6 @@
 
 
 const Web3Utils = require("web3-utils");
-const assert = require("assert");
 
 class Contract {
     constructor() {
@@ -141,7 +140,9 @@ class Contract {
     msize()  { this.code.push(0x59); }
     gas()  { this.code.push(0x5a); }
     label(name)  {
-        assert(typeof this.labels[name] == "undefined", "Label already defined");
+        if (typeof this.labels[name] != "undefined") {
+            throw new Error("Label already defined");
+        }
         this.labels[name] = this.code.length;
         this.code.push(0x5b);
 
@@ -150,20 +151,23 @@ class Contract {
 
     push(data) {
         const d = Web3Utils.hexToBytes(Web3Utils.toHex(data));
-        assert(d.length>0);
-        assert(d.length<=32);
+        if (d.length == 0 || d.length > 32) {
+            throw new Error("Assertion failed");
+        }
         this.code = this.code.concat([0x5F + d.length], d);
     }
 
     dup(n) {
-        assert(n>=0);
-        assert(n<16);
+        if (n < 0 || n >= 16) {
+            throw new Error("Assertion failed");
+        }
         this.code.push(0x80 + n);
     }
 
     swap(n) {
-        assert(n>=1);
-        assert(n<=16);
+        if (n < 1 || n > 16) {
+            throw new Error("Assertion failed");
+        }
         this.code.push(0x8f + n);
     }
 
diff --git a/src/pedersenHash.js b/src/pedersenHash.js
index a055297..e14f089 100644
--- a/src/pedersenHash.js
+++ b/src/pedersenHash.js
@@ -1,7 +1,6 @@
 const bn128 = require("snarkjs").bn128;
 const bigInt = require("snarkjs").bigInt;
 const babyJub = require("./babyjub");
-const assert = require("assert");
 const createBlakeHash = require("blake-hash");
 
 const GENPOINT_PREFIX = "PedersenGenerator";
@@ -73,7 +72,9 @@ function getBasePoint(pointIdx) {
 
     const p8 = babyJub.mulPointEscalar(p, 8);
 
-    assert(babyJub.inSubgroup(p8), "Point not in curve");
+    if (!babyJub.inSubgroup(p8)) {
+        throw new Error("Point not in curve");
+    }
 
     bases[pointIdx] = p8;
     return p8;
diff --git a/test/eddsa.js b/test/eddsa.js
index 0dd29c4..8292a89 100644
--- a/test/eddsa.js
+++ b/test/eddsa.js
@@ -2,6 +2,7 @@ const chai = require("chai");
 const path = require("path");
 const snarkjs = require("snarkjs");
 const compiler = require("circom");
+// const crypto = require("crypto");
 
 const eddsa = require("../src/eddsa.js");
 const babyJub = require("../src/babyjub.js");
@@ -45,7 +46,7 @@ describe("EdDSA test", function () {
     it("Sign a single 10 bytes from 0 to 9", async () => {
         const msg = Buffer.from("00010203040506070809", "hex");
 
-//        const prvKey = eddsa.cratePrvKey();
+//        const prvKey = crypto.randomBytes(32);
 
         const prvKey = Buffer.from("0001020304050607080900010203040506070809000102030405060708090001", "hex");