babyjub.js adapted

package-lock.json

@@ -1529,6 +1529,21 @@
       "resolved": "https://registry.npmjs.org/fast-levenshtein/-/fast-levenshtein-2.0.6.tgz",
       "integrity": "sha1-PYpcZog6FqMMqGQ+hR8Zuqd5eRc="
     },
+    "fflib": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/fflib/-/fflib-0.0.1.tgz",
+      "integrity": "sha512-bWTudSfCjkNkOOeSNQf8DmBidxxuzqyjeIdZBfY38T7R+jt381sdx1SYpyve5MQdDlQg1k7UHeb0L/J8WWFWYA==",
+      "requires": {
+        "big-integer": "^1.6.48"
+      },
+      "dependencies": {
+        "big-integer": {
+          "version": "1.6.48",
+          "resolved": "https://registry.npmjs.org/big-integer/-/big-integer-1.6.48.tgz",
+          "integrity": "sha512-j51egjPa7/i+RdiRuJbPdJ2FIUYYPhvYLjzoYbcMMm62ooO6F94fETG4MTs46zPAF9Brs04OajboA/qTGuz78w=="
+        }
+      }
+    },
     "figures": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/figures/-/figures-2.0.0.tgz",

package.json

@@ -27,6 +27,7 @@
     "blake-hash": "^1.1.0",
     "blake2b": "^2.1.3",
     "circom": "0.0.35",
+    "fflib": "0.0.1",
     "snarkjs": "^0.1.20",
     "typedarray-to-buffer": "^3.1.5",
     "web3": "^1.0.0-beta.55"

src/babyjub.js

@@ -1,5 +1,6 @@
-const bn128 = require("snarkjs").bn128;
-const bigInt = require("snarkjs").bigInt;
+const bigInt = require("big-integer");
+const ZqField = require("fflib").ZqField;
+const utils = require("./utils.js");
 
 exports.addPoint = addPoint;
 exports.mulPointEscalar = mulPointEscalar;
@@ -16,14 +17,14 @@ exports.Base8 = [
     bigInt("16950150798460657717958625567821834550301663161624707787222815936182638968203")
 ];
 exports.order = bigInt("21888242871839275222246405745257275088614511777268538073601725287587578984328");
-exports.subOrder = exports.order.shr(3);
-exports.p = bn128.r;
+exports.subOrder = exports.order.shiftRight(3);
+exports.p = bigInt("21888242871839275222246405745257275088548364400416034343698204186575808495617");
 exports.A = bigInt("168700");
 exports.D = bigInt("168696");
 
 
 function addPoint(a,b) {
-    const q = bn128.r;
+    const F = new ZqField(exports.p);
 
     const res = [];
 
@@ -31,8 +32,25 @@ function addPoint(a,b) {
      res[0] = bigInt((a[0]*b[1] + b[0]*a[1]) *  bigInt(bigInt("1") + d*a[0]*b[0]*a[1]*b[1]).inverse(q)).affine(q);
     res[1] = bigInt((a[1]*b[1] - cta*a[0]*b[0]) * bigInt(bigInt("1") - d*a[0]*b[0]*a[1]*b[1]).inverse(q)).affine(q);
     */
-    res[0] = bigInt((bigInt(a[0]).mul(b[1]).add(bigInt(b[0]).mul(a[1]))).mul(bigInt(bigInt("1").add(exports.D.mul(a[0]).mul(b[0]).mul(a[1]).mul(b[1]))).inverse(q))).affine(q);
-    res[1] = bigInt((bigInt(a[1]).mul(b[1]).sub(exports.A.mul(a[0]).mul(b[0]))).mul(bigInt(bigInt("1").sub(exports.D.mul(a[0]).mul(b[0]).mul(a[1]).mul(b[1]))).inverse(q))).affine(q);
+
+    const beta = F.mul(a[0],b[1]);
+    const gamma = F.mul(a[1],b[0]);
+    const delta = F.mul(
+        F.sub(a[1], F.mul(exports.A, a[0])),
+        F.add(b[0], b[1])
+    );
+    const tau = F.mul(beta, gamma);
+    const dtau = F.mul(exports.D, tau);
+
+    res[0] = F.div(
+        F.add(beta, gamma),
+        F.add(bigInt.one, dtau)
+    );
+
+    res[1] = F.div(
+        F.add(delta, F.sub(F.mul(exports.A,beta), gamma)),
+        F.sub(bigInt.one, dtau)
+    );
 
     return res;
 }
@@ -47,7 +65,7 @@ function mulPointEscalar(base, e) {
             res = addPoint(res, exp);
         }
         exp = addPoint(exp, exp);
-        rem = rem.shr(1);
+        rem = rem.shiftRight(1);
     }
 
     return res;
@@ -60,12 +78,12 @@ function inSubgroup(P) {
 }
 
 function inCurve(P) {
-    const F = bn128.Fr;
+    const F = new ZqField(exports.p);
 
     const x2 = F.square(P[0]);
     const y2 = F.square(P[1]);
 
-    if (!F.equals(
+    if (!F.eq(
         F.add(F.mul(exports.A, x2), y2),
         F.add(F.one, F.mul(F.mul(x2, y2), exports.D)))) return false;
 
@@ -73,15 +91,15 @@ function inCurve(P) {
 }
 
 function packPoint(P) {
-    const buff = bigInt.leInt2Buff(P[1], 32);
-    if (P[0].greater(exports.p.shr(1))) {
+    const buff = utils.leInt2Buff(P[1], 32);
+    if (P[0].greater(exports.p.shiftRight(1))) {
         buff[31] = buff[31] | 0x80;
     }
     return buff;
 }
 
 function unpackPoint(_buff) {
-    const F = bn128.Fr;
+    const F = new ZqField(exports.p);
 
     const buff = Buffer.from(_buff);
     let sign = false;
@@ -90,7 +108,7 @@ function unpackPoint(_buff) {
         sign = true;
         buff[31] = buff[31] & 0x7F;
     }
-    P[1] = bigInt.leBuff2int(buff);
+    P[1] = utils.leBuff2int(buff);
     if (P[1].greaterOrEquals(exports.p)) return null;
 
     const y2 = F.square(P[1]);
@@ -103,7 +121,7 @@ function unpackPoint(_buff) {
 
     if (sign) x = F.neg(x);
 
-    P[0] = F.affine(x);
+    P[0] = x;
 
     return P;
 }

test/babyjub_js.js

@@ -1,7 +1,5 @@
 const chai = require("chai");
-const path = require("path");
-const snarkjs = require("snarkjs");
-const compiler = require("circom");
+const bigInt = require("big-integer");
 const babyjub = require("../src/babyjub.js");
 
 const assert = chai.assert;
@@ -16,14 +14,14 @@ describe("Baby Jub js test", function () {
     it("Should add point (0,1) and (0,1)", () => {
 
         const p1 = [
-            snarkjs.bigInt(0),
-            snarkjs.bigInt(1)];
+            bigInt(0),
+            bigInt(1)];
         const p2 = [
-            snarkjs.bigInt(0),
-            snarkjs.bigInt(1)
+            bigInt(0),
+            bigInt(1)
         ];
 
-        const out = babyjub.addPoint(p1, p2)
+        const out = babyjub.addPoint(p1, p2);
         assert(out[0].equals(0));
         assert(out[1].equals(1));
     });
@@ -41,43 +39,43 @@ describe("Baby Jub js test", function () {
     it("Should add 2 same numbers", () => {
 
         const p1 = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
         const p2 = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
 
-        const out = babyjub.addPoint(p1, p2)
-        assert(out[0].equals(snarkjs.bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365")));
-        assert(out[1].equals(snarkjs.bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889")));
+        const out = babyjub.addPoint(p1, p2);
+        assert(out[0].equals(bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365")));
+        assert(out[1].equals(bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889")));
     });
 
     it("Should add 2 different numbers", () => {
 
         const p1 = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
         const p2 = [
-            snarkjs.bigInt("16540640123574156134436876038791482806971768689494387082833631921987005038935"),
-            snarkjs.bigInt("20819045374670962167435360035096875258406992893633759881276124905556507972311"),
+            bigInt("16540640123574156134436876038791482806971768689494387082833631921987005038935"),
+            bigInt("20819045374670962167435360035096875258406992893633759881276124905556507972311"),
         ];
 
-        const out = babyjub.addPoint(p1, p2)
+        const out = babyjub.addPoint(p1, p2);
 
-        assert(out[0].equals(snarkjs.bigInt("7916061937171219682591368294088513039687205273691143098332585753343424131937")));
-        assert(out[1].equals(snarkjs.bigInt("14035240266687799601661095864649209771790948434046947201833777492504781204499")));
+        assert(out[0].equals(bigInt("7916061937171219682591368294088513039687205273691143098332585753343424131937")));
+        assert(out[1].equals(bigInt("14035240266687799601661095864649209771790948434046947201833777492504781204499")));
     });
 
     it("should mulPointEscalar 0", () => {
         const p = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
 
-        const r = babyjub.mulPointEscalar(p, snarkjs.bigInt("3"));
+        const r = babyjub.mulPointEscalar(p, bigInt("3"));
         let r2 = babyjub.addPoint(p, p);
         r2 = babyjub.addPoint(r2, p);
         assert.equal(r2[0].toString(), r[0].toString());
@@ -88,65 +86,65 @@ describe("Baby Jub js test", function () {
 
     it("should mulPointEscalar 1", () => {
         const p = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
 
-        const r = babyjub.mulPointEscalar(p, snarkjs.bigInt("14035240266687799601661095864649209771790948434046947201833777492504781204499"));
+        const r = babyjub.mulPointEscalar(p, bigInt("14035240266687799601661095864649209771790948434046947201833777492504781204499"));
         assert.equal(r[0].toString(), "17070357974431721403481313912716834497662307308519659060910483826664480189605");
         assert.equal(r[1].toString(), "4014745322800118607127020275658861516666525056516280575712425373174125159339");
     });
 
     it("should mulPointEscalar 2", () => {
         const p = [
-            snarkjs.bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
-            snarkjs.bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
+            bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
+            bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
         ];
 
-        const r = babyjub.mulPointEscalar(p, snarkjs.bigInt("20819045374670962167435360035096875258406992893633759881276124905556507972311"));
+        const r = babyjub.mulPointEscalar(p, bigInt("20819045374670962167435360035096875258406992893633759881276124905556507972311"));
         assert.equal(r[0].toString(), "13563888653650925984868671744672725781658357821216877865297235725727006259983");
         assert.equal(r[1].toString(), "8442587202676550862664528699803615547505326611544120184665036919364004251662");
     });
 
     it("should inCurve 1", () => {
         const p = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
         assert(babyjub.inCurve(p));
     });
 
     it("should inCurve 2", () => {
         const p = [
-            snarkjs.bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
-            snarkjs.bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
+            bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
+            bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
         ];
         assert(babyjub.inCurve(p));
     });
 
     it("should inSubgroup 1", () => {
         const p = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
         assert(babyjub.inSubgroup(p));
     });
 
     it("should inSubgroup 2", () => {
         const p = [
-            snarkjs.bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
-            snarkjs.bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
+            bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
+            bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
         ];
         assert(babyjub.inSubgroup(p));
     });
 
     it("should packPoint - unpackPoint 1", () => {
         const p = [
-            snarkjs.bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
-            snarkjs.bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
+            bigInt("17777552123799933955779906779655732241715742912184938656739573121738514868268"),
+            bigInt("2626589144620713026669568689430873010625803728049924121243784502389097019475"),
         ];
         const buf = babyjub.packPoint(p);
-        assert.equal(buf.toString('hex'), '53b81ed5bffe9545b54016234682e7b2f699bd42a5e9eae27ff4051bc698ce85');
+        assert.equal(buf.toString("hex"), "53b81ed5bffe9545b54016234682e7b2f699bd42a5e9eae27ff4051bc698ce85");
         const p2 = babyjub.unpackPoint(buf);
         assert.equal(p2[0].toString(), "17777552123799933955779906779655732241715742912184938656739573121738514868268");
         assert.equal(p2[1].toString(), "2626589144620713026669568689430873010625803728049924121243784502389097019475");
@@ -154,11 +152,11 @@ describe("Baby Jub js test", function () {
 
     it("should packPoint - unpackPoint 2", () => {
         const p = [
-            snarkjs.bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
-            snarkjs.bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
+            bigInt("6890855772600357754907169075114257697580319025794532037257385534741338397365"),
+            bigInt("4338620300185947561074059802482547481416142213883829469920100239455078257889"),
         ];
         const buf = babyjub.packPoint(p);
-        assert.equal(buf.toString('hex'), 'e114eb17eddf794f063a68fecac515e3620e131976108555735c8b0773929709');
+        assert.equal(buf.toString("hex"), "e114eb17eddf794f063a68fecac515e3620e131976108555735c8b0773929709");
         const p2 = babyjub.unpackPoint(buf);
         assert.equal(p2[0].toString(), "6890855772600357754907169075114257697580319025794532037257385534741338397365");
         assert.equal(p2[1].toString(), "4338620300185947561074059802482547481416142213883829469920100239455078257889");