Merge other basic circuits here

circuits/eddsa.circom

@@ -0,0 +1,119 @@
+include "compconstant.circom";
+include "pointbits.circom";
+include "pedersen.circom";
+include "escalarmulany.circom";
+include "escalarmulfix.circom";
+
+template EdDSAVerifier(n) {
+    signal input msg[n];
+
+    signal input A[256];
+    signal input R8[256];
+    signal input S[256];
+
+    signal Ax;
+    signal Ay;
+
+    signal R8x;
+    signal R8y;
+
+    var i;
+
+// Ensure S<Subgroup Order
+
+    component  compConstant = CompConstant(2736030358979909402780800718157159386076813972158567259200215660948447373040);
+
+    for (i=0; i<254; i++) {
+        S[i] ==> compConstant.in[i];
+    }
+    compConstant.out === 0;
+    S[254] === 0;
+    S[255] === 0;
+
+// Convert A to Field elements (And verify A)
+
+    component bits2pointA = Bits2Point_Strict();
+
+    for (i=0; i<256; i++) {
+        bits2pointA.in[i] <== A[i];
+    }
+    Ax <== bits2pointA.out[0];
+    Ay <== bits2pointA.out[1];
+
+// Convert R8 to Field elements (And verify R8)
+
+    component bits2pointR8 = Bits2Point_Strict();
+
+    for (i=0; i<256; i++) {
+        bits2pointR8.in[i] <== R8[i];
+    }
+    R8x <== bits2pointR8.out[0];
+    R8y <== bits2pointR8.out[1];
+
+// Calculate the h = H(R,A, msg)
+
+    component hash = Pedersen(512+n);
+
+    for (i=0; i<256; i++) {
+        hash.in[i] <== R8[i];
+        hash.in[256+i] <== A[i];
+    }
+    for (i=0; i<n; i++) {
+        hash.in[512+i] <== msg[i];
+    }
+
+    component point2bitsH = Point2Bits_Strict();
+    point2bitsH.in[0] <== hash.out[0];
+    point2bitsH.in[1] <== hash.out[1];
+
+// Calculate second part of the right side:  right2 = h*8*A
+
+    // Multiply by 8 by adding it 3 times.  This also ensure that the result is in
+    // the subgroup.
+    component dbl1 = BabyDbl();
+    dbl1.x <== Ax;
+    dbl1.y <== Ay;
+    component dbl2 = BabyDbl();
+    dbl2.x <== dbl1.xout;
+    dbl2.y <== dbl1.yout;
+    component dbl3 = BabyDbl();
+    dbl3.x <== dbl2.xout;
+    dbl3.y <== dbl2.yout;
+
+    // We check that A is not zero.
+    component isZero = IsZero();
+    isZero.in <== dbl3.x;
+    isZero.out === 0;
+
+    component mulAny = EscalarMulAny(256);
+    for (i=0; i<256; i++) {
+        mulAny.e[i] <== point2bitsH.out[i];
+    }
+    mulAny.p[0] <== dbl3.xout;
+    mulAny.p[1] <== dbl3.yout;
+
+
+// Compute the right side: right =  R8 + right2
+
+    component addRight = BabyAdd();
+    addRight.x1 <== R8x;
+    addRight.y1 <== R8y;
+    addRight.x2 <== mulAny.out[0];
+    addRight.y2 <== mulAny.out[1];
+
+// Calculate left side of equation left = S*B8
+
+    var BASE8 = [
+        17777552123799933955779906779655732241715742912184938656739573121738514868268,
+        2626589144620713026669568689430873010625803728049924121243784502389097019475
+    ];
+    component mulFix = EscalarMulFix(256, BASE8);
+    for (i=0; i<256; i++) {
+        mulFix.e[i] <== S[i];
+    }
+
+// Do the comparation left == right
+
+    mulFix.out[0] === addRight.xout;
+    mulFix.out[1] === addRight.yout;
+}