adds alias check for babyjubjub

circuits/aliascheck.circom

@@ -21,7 +21,6 @@ include "compconstant.circom";
 
 
 template AliasCheck() {
-
     signal input in[254];
 
     component  compConstant = CompConstant(-1);
@@ -30,3 +29,14 @@ template AliasCheck() {
 
     compConstant.out === 0;
 }
+
+template AliasCheckBabyJub() {
+    signal input in[251];
+
+    component  compConstant = CompConstant(2736030358979909402780800718157159386076813972158567259200215660948447373040);
+
+    for (var i=0; i<251; i++) in[i] ==> compConstant.in[i];
+    for (var i=0; i<3; i++) 0 ==> compConstant.in[251+i];
+
+    compConstant.out === 0;
+}

test/aliascheck.js

@@ -56,7 +56,8 @@ describe("Aliascheck test", () => {
             circuit.calculateWitness({in: inp});
             assert(false);
         } catch(err) {
-            assert.equal(err.message, "Constraint doesn't match: 1 != 0");
+            assert(err.message.indexOf("Constraint doesn't match") >= 0);
+            assert(err.message.indexOf("1 != 0") >= 0);
         }
     });
 
@@ -67,7 +68,8 @@ describe("Aliascheck test", () => {
             circuit.calculateWitness({in: inp});
             assert(false);
         } catch(err) {
-                assert.equal(err.message, "Constraint doesn't match: 1 != 0");
+            assert(err.message.indexOf("Constraint doesn't match") >= 0);
+            assert(err.message.indexOf("1 != 0") >= 0);
         }
     });
 

test/aliascheckbabyjub.js

@@ -0,0 +1,75 @@
+const chai = require("chai");
+const path = require("path");
+const snarkjs = require("snarkjs");
+const compiler = require("circom");
+
+const assert = chai.assert;
+
+const bigInt = snarkjs.bigInt;
+
+function print(circuit, w, s) {
+    console.log(s + ": " + w[circuit.getSignalIdx(s)]);
+}
+
+function getBits(v, n) {
+    const res = [];
+    for (let i=0; i<n; i++) {
+        if (v.shr(i).isOdd()) {
+            res.push(bigInt.one);
+        } else {
+            res.push(bigInt.zero);
+        }
+    }
+    return res;
+}
+
+const r = bigInt("2736030358979909402780800718157159386076813972158567259200215660948447373041");
+
+describe("Aliascheck test", () => {
+    let circuit;
+    before( async() => {
+        const cirDef = await compiler(path.join(__dirname, "circuits", "aliascheckbabyjub_test.circom"));
+
+        circuit = new snarkjs.Circuit(cirDef);
+
+        console.log("NConstrains: " + circuit.nConstraints);
+    });
+
+    it("Satisfy the aliastest 0", async () => {
+        const inp = getBits(bigInt.zero, 251);
+        circuit.calculateWitness({in: inp});
+    });
+
+    it("Satisfy the aliastest 3", async () => {
+        const inp = getBits(bigInt(3), 251);
+        circuit.calculateWitness({in: inp});
+    });
+
+    it("Satisfy the aliastest r-1", async () => {
+        const inp = getBits(r.sub(bigInt.one), 251);
+        circuit.calculateWitness({in: inp});
+    });
+
+    it("Nhot not satisfy an input of r", async () => {
+        const inp = getBits(r, 251);
+        try {
+            circuit.calculateWitness({in: inp});
+            assert(false);
+        } catch(err) {
+            assert(err.message.indexOf("Constraint doesn't match") >= 0);
+            assert(err.message.indexOf("1 != 0") >= 0);
+        }
+    });
+
+    it("Nhot not satisfy all ones", async () => {
+        const inp = getBits(bigInt(1).shl(251).sub(bigInt(1)), 251);
+        try {
+            circuit.calculateWitness({in: inp});
+            assert(false);
+        } catch(err) {
+            assert(err.message.indexOf("Constraint doesn't match") >= 0);
+            assert(err.message.indexOf("1 != 0") >= 0);
+        }
+    });
+
+});

test/babyjub.js

@@ -100,7 +100,8 @@ describe("Baby Jub test", function () {
             circuitTest.calculateWitness({x: 1, y: 0});
             assert(false, "Should be a valid point");
         } catch(err) {
-            assert.equal(err.message, "Constraint doesn't match: 168700 != 1");
+            assert(err.message.indexOf("Constraint doesn't match") >= 0);
+            assert(err.message.indexOf("168700 != 1") >= 0);
         }
     });
 
@@ -121,5 +122,4 @@ describe("Baby Jub test", function () {
         const w = circuitPbk.calculateWitness(input);
         assert(circuitPbk.checkWitness(w));
     });
-
 });

test/circuits/aliascheckbabyjub_test.circom

@@ -0,0 +1,3 @@
+include "../../circuits/aliascheck.circom";
+
+component main = AliasCheckBabyJub()