Fix bls12-381

main.js

@@ -20,4 +20,5 @@ export {default as ChaCha} from "./src/chacha.js";
 
 export {default as BigBuffer} from "./src/bigbuffer.js";
 
+export {getCurveFromR, getCurveFromQ, getCurveFromName} from "./src/curves.js";
 

package.json

@@ -33,7 +33,7 @@
   "homepage": "https://github.com/iden3/ffjs#readme",
   "dependencies": {
     "big-integer": "^1.6.48",
-    "wasmcurves": "0.0.11",
+    "wasmcurves": "0.0.12",
     "worker-threads": "^1.0.0"
   },
   "devDependencies": {

src/curves.js

@@ -0,0 +1,51 @@
+import * as Scalar from "./scalar.js";
+import {default as buildBn128} from "./bn128.js";
+import {default as buildBls12381} from "./bn128.js";
+
+const bls12381r = Scalar.e("73eda753299d7d483339d80809a1d80553bda402fffe5bfeffffffff00000001", 16);
+const bn128r = Scalar.e("21888242871839275222246405745257275088548364400416034343698204186575808495617");
+
+const bls12381q = Scalar.e("1a0111ea397fe69a4b1ba7b6434bacd764774b84f38512bf6730d2a0f6b0f6241eabfffeb153ffffb9feffffffffaaab", 16);
+const bn128q = Scalar.e("21888242871839275222246405745257275088696311157297823662689037894645226208583");
+
+export async function getCurveFromR(r) {
+    let curve;
+    if (Scalar.eq(r, bn128r)) {
+        curve = await buildBn128();
+    } else if (Scalar.eq(r, bls12381r)) {
+        curve = await buildBls12381();
+    } else {
+        throw new Error(`Curve not supported: ${Scalar.toString(r)}`);
+    }
+    return curve;
+}
+
+export async function getCurveFromQ(q) {
+    let curve;
+    if (Scalar.eq(q, bn128q)) {
+        curve = await buildBn128();
+    } else if (Scalar.eq(q, bls12381q)) {
+        curve = await buildBls12381();
+    } else {
+        throw new Error(`Curve not supported: ${Scalar.toString(q)}`);
+    }
+    return curve;
+}
+
+export async function getCurveFromName(name) {
+    let curve;
+    const normName = normalizeName(name);
+    if (["BN128", "BN254", "ALTBN128"].indexOf(normName) >= 0) {
+        curve = await buildBn128();
+    } else if (["BLS12381"].indexOf(normName) >= 0) {
+        curve = await buildBls12381();
+    } else {
+        throw new Error(`Curve not supported: ${name}`);
+    }
+    return curve;
+
+    function normalizeName(n) {
+        return n.toUpperCase().match(/[A-Za-z0-9]+/g).join("");
+    }
+
+}

src/fsqrt.js

@@ -51,7 +51,7 @@ function alg5_tonelliShanks(F) {
     while (F.eq(c0, F.one)) {
         const c = F.random();
         F.sqrt_z = F.pow(c, F.sqrt_t);
-        c0 = F.pow(F.sqrt_z, 1 << (F.sqrt_s-1) );
+        c0 = F.pow(F.sqrt_z, 2 ** (F.sqrt_s-1) );
     }
 
     F.sqrt_tm1d2 = Scalar.div(Scalar.sub(F.sqrt_t, 1),2);
@@ -60,7 +60,7 @@ function alg5_tonelliShanks(F) {
         const F=this;
         if (F.isZero(a)) return F.zero;
         let w = F.pow(a, F.sqrt_tm1d2);
-        const a0 = F.pow( F.mul(F.square(w), a), 1 << (F.sqrt_s-1) );
+        const a0 = F.pow( F.mul(F.square(w), a), 2 ** (F.sqrt_s-1) );
         if (F.eq(a0, F.negone)) return null;
 
         let v = F.sqrt_s;

src/wasm_curve.js

@@ -374,6 +374,16 @@ export default class WasmCurve {
         return this.fromObject(a);
     }
 
+    x(a) {
+        const tmp = this.toAffine(a);
+        return tmp.slice(0, this.F.n8);
+    }
+
+    y(a) {
+        const tmp = this.toAffine(a);
+        return tmp.slice(this.F.n8);
+    }
+
 }
 
 

src/wasm_field2.js

@@ -92,6 +92,10 @@ export default class WasmField2 {
         return this.op2("_mul", a, b);
     }
 
+    mul1(a,b) {
+        return this.op2("_mul1", a, b);
+    }
+
     div(a, b) {
         this.tm.setBuff(this.pOp1, a);
         this.tm.setBuff(this.pOp2, b);
@@ -170,5 +174,13 @@ export default class WasmField2 {
         return buff;
     }
 
+    c1(a) {
+        return a.slice(0, this.F.n8);
+    }
+
+    c2(a) {
+        return a.slice(this.F.n8);
+    }
+
 }
 

src/wasm_field3.js

@@ -181,6 +181,18 @@ export default class WasmField3 {
         return buff;
     }
 
+    c1(a) {
+        return a.slice(0, this.F.n8);
+    }
+
+    c2(a) {
+        return a.slice(this.F.n8, this.F.n8*2);
+    }
+
+    c3(a) {
+        return a.slice(this.F.n8*2);
+    }
+
 }