Iota Circom circuit implemented

circuits/iota.circom

@@ -0,0 +1,41 @@
+pragma circom 2.0.0;
+
+include "./utils.circom";
+
+template RC(r) {
+    signal output out[64];
+    var rc[24] = [
+        0x0000000000000001, 0x0000000000008082, 0x800000000000808A,
+        0x8000000080008000, 0x000000000000808B, 0x0000000080000001,
+        0x8000000080008081, 0x8000000000008009, 0x000000000000008A,
+        0x0000000000000088, 0x0000000080008009, 0x000000008000000A,
+        0x000000008000808B, 0x800000000000008B, 0x8000000000008089,
+        0x8000000000008003, 0x8000000000008002, 0x8000000000000080,
+        0x000000000000800A, 0x800000008000000A, 0x8000000080008081,
+        0x8000000000008080, 0x0000000080000001, 0x8000000080008008
+    ];
+    for (var i=0; i<64; i++) {
+        out[i] <== (rc[r] >> i) & 1;
+    }
+}
+
+template Iota(r) {
+    signal input in[25*64];
+    signal output out[25*64];
+    var i;
+
+    component rc = RC(r);
+
+    component iota = XorArray(64);
+    for (var i=0; i<64; i++) {
+        iota.a[i] <== in[i];
+        iota.b[i] <== rc.out[i];
+    }
+    for (i=0; i<64; i++) {
+        out[i] <== iota.out[i];
+    }
+    for (i=64; i<25*64; i++) {
+        out[i] <== in[i];
+    }
+}
+

test/circuits/iota10_test.circom

@@ -0,0 +1,6 @@
+pragma circom 2.0.0;
+
+include "../../circuits/iota.circom";
+
+component main = Iota(10);
+

test/circuits/iota3_test.circom

@@ -0,0 +1,6 @@
+pragma circom 2.0.0;
+
+include "../../circuits/iota.circom";
+
+component main = Iota(3);
+

test/keccak256.js

@@ -183,3 +183,38 @@ describe("Chi test", function () {
 	assert.deepEqual(stateOutU64, expectedOut);
     });
 });
+
+describe("Iota test", function () {
+    this.timeout(100000);
+
+    it ("Iota 3 (testvector generated from go)", async () => {
+	const cir = await wasm_tester(path.join(__dirname, "circuits", "iota3_test.circom"));
+
+	const input = [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24];
+	const expectedOut = [9223372039002292224,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24];
+	const stateIn = u64ArrayToBits(input);
+	const expectedOutBits = u64ArrayToBits(expectedOut);
+
+	const witness = await cir.calculateWitness({ "in": stateIn }, true);
+
+	const stateOut = witness.slice(1, 1+(25*64));
+	const stateOutU64 = bitsToU64Array(stateOut);
+	// console.log(stateOutU64, expectedOut);
+	assert.deepEqual(stateOutU64, expectedOut);
+    });
+    it ("Iota 10 (testvector generated from go)", async () => {
+	const cir = await wasm_tester(path.join(__dirname, "circuits", "iota10_test.circom"));
+
+	const input = [9223372039002292224,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24];
+	const expectedOut = [9223372036854775817,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24];
+	const stateIn = u64ArrayToBits(input);
+	const expectedOutBits = u64ArrayToBits(expectedOut);
+
+	const witness = await cir.calculateWitness({ "in": stateIn }, true);
+
+	const stateOut = witness.slice(1, 1+(25*64));
+	const stateOutU64 = bitsToU64Array(stateOut);
+	// console.log(stateOutU64, expectedOut);
+	assert.deepEqual(stateOutU64, expectedOut);
+    });
+});