M circuits/withdraw.circom → circuits/withdraw.circom

@@ -3,49 +3,61 @@ # withdraw.circom
 
 WARNING: WIP, very initial version of the miksi circuit
 
-                     +--------+
-PUB_coinCode+------->+        |
-                     |        |        +----+
-PUB_amount+--------->+Poseidon+------->+ == +<-----+PUB_commitment
-                     |        |        +----+
-PRI_secret+--------->+        |
-                     +--------+
 
-                +----+
-PUB_address+--->+ != +<---+0
-                +----+
+
+                                               +----------+
+                                               |          |
+PUB_nullifier+------>+----------+              |          |
+PUB_coinCode+------->+          |              | SMT      +<------+PRI_siblings
+                     |          |              | Poseidon |
+PUB_amount+--------->+ Poseidon +------------->+ Verifier |
+                     |          |              |          +<------+PUB_root
+PRI_secret+--------->+          |              |          |        +
+                     +----------+              +----------+        |
+                                                                   |
+                             +----+                  +----+        |
+             PUB_address+--->+ != +<-------+0+------>+ != +<-------+
+                             +----+                  +----+
 
 
 
 */
 
-include "../node_modules/circomlib/circuits/babyjub.circom";
 include "../node_modules/circomlib/circuits/comparators.circom";
 include "../node_modules/circomlib/circuits/poseidon.circom";
-include "../node_modules/circomlib/circuits/bitify.circom";
 include "../node_modules/circomlib/circuits/smt/smtverifier.circom";
-include "../node_modules/circomlib/circuits/smt/smtprocessor.circom";
 
-template Withdraw() {
+template Withdraw(nLevels) {
 	signal input coinCode;
 	signal input amount;
-	signal input commitment;
 	signal private input secret;
+	signal input nullifier;
+	signal private input siblings[nLevels];
+	signal input root;
 	signal input address;
 
-	component hash = Poseidon(3, 6, 8, 57);
+	component hash = Poseidon(4, 6, 8, 57);
 	hash.inputs[0] <== coinCode;
 	hash.inputs[1] <== amount;
 	hash.inputs[2] <== secret;
-
-	component eq = IsEqual();
-	eq.in[0] <== hash.out;
-	eq.in[1] <== commitment;
-	eq.out === 1;
+	hash.inputs[3] <== nullifier;
 
 	component z = IsZero();
 	z.in <== address;
 	z.out === 0;
+
+	component smtV = SMTVerifier(nLevels);
+	smtV.enabled <== 1;
+	smtV.fnc <== 0;
+	smtV.root <== root;
+	for (var i=0; i<nLevels; i++) {
+		smtV.siblings[i] <== siblings[i];
+	}
+	smtV.oldKey <== 0;
+	smtV.oldValue <== 0;
+	smtV.isOld0 <== 0;
+	smtV.key <== hash.out;
+	smtV.value <== 0;
 }
 
-component main = Withdraw();
+component main = Withdraw(5);

M test/circuits/withdraw.test.ts → test/circuits/withdraw.test.ts

@@ -3,6 +3,7 @@ const tester = require("circom").tester;
 const chai = require("chai");
 const assert = chai.assert;
 const circomlib = require("circomlib");
+const smt = require("circomlib").smt;
 
 export {};
 
@@ -16,20 +17,39 @@ path.join(__dirname, "../../circuits", "withdraw.circom"),
             {reduceConstraints: false}
         );
 
-        // const secret = Math.floor(Math.random()*1000).toString();
-        const secret = "123456789";
+        const nLevels = 5;
+        const secret = "1234567890";
 
-        const coinCode = "1";
-        const amount = "100";
+        const coinCode = "0";
+        const amount = '1000000000000000000';
+        const nullifier = "567891234";
 
         const poseidon = circomlib.poseidon.createHash(6, 8, 57);
-        const commitment = poseidon([coinCode, amount, secret]).toString();
+        const commitment = poseidon([coinCode, amount, secret, nullifier]).toString();
 
+        // add commitment into SMT
+        let tree = await smt.newMemEmptyTrie();
+        await tree.insert(commitment, 0);
+        await tree.insert(1, 0);
+        await tree.insert(2, 0);
+        console.log("root", tree.root);
+        const res = await tree.find(commitment);
+        assert(res.found);
+        let siblings = res.siblings;
+        while (siblings.length < nLevels) {
+            siblings.push("0");
+        };
+        console.log("siblings", siblings);
+
+        let root = tree.root;
+        
         const witness = await circuit.calculateWitness({
             "coinCode": coinCode,
             "amount": amount,
-            "commitment": commitment,
             "secret": secret,
+            "nullifier": nullifier,
+            "siblings": siblings,
+            "root": root,
             "address": "987654321"
         });
         await circuit.checkConstraints(witness);