miksi-core/circuits/withdraw.circom

/*
# withdraw.circom

WARNING: WIP, very initial version of the miksi circuit


                     +----------+
                     |          |
PRI_secret+--------->+ Poseidon +<------+PRI_key+---------+
          |          |          |                         |
          |          +----------+      +----+             |
          |            nullifier+----->+ != +<-----+0     |
          |                +           +----+             v
          |                |                           +--+-------+
          |                v                           |          |
          |          +-----+----+                      |          |
          +--------->+          |                      | SMT      +<------+PRI_siblings
                     |          +--------------------->+ Poseidon |
PUB_coinCode+------->+ Poseidon |                      | Verifier |
                     |          |                      |          +<------+PUB_root
PUB_amount+--------->+          |                      |          |        +
                     +----------+                      +----------+        |
                                                                           |
                                                                           |
                             +----+                          +----+        |
             PUB_address+--->+ != +<-------+0+-------------->+ != +<-------+
                             +----+                          +----+



*/

include "../node_modules/circomlib/circuits/comparators.circom";
include "../node_modules/circomlib/circuits/poseidon.circom";
include "../node_modules/circomlib/circuits/smt/smtverifier.circom";

template Withdraw(nLevels) {
	signal input coinCode;
	signal input amount;
	signal private input secret;
	signal input nullifier;
	signal private input siblings[nLevels];
	signal input root;
	signal input address;
	signal private input key;

	component nullifierCmp = Poseidon(2, 6, 8, 57);
	nullifierCmp.inputs[0] <== key;
	nullifierCmp.inputs[1] <== secret;

	component nullifierCheck = IsEqual();
	nullifierCheck.in[0] <== nullifierCmp.out;
	nullifierCheck.in[1] <== nullifier;
	nullifierCheck.out === 1;

	component hash = Poseidon(4, 6, 8, 57);
	hash.inputs[0] <== coinCode;
	hash.inputs[1] <== amount;
	hash.inputs[2] <== secret;
	hash.inputs[3] <== nullifierCmp.out;

	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 <== key;
	smtV.value <== hash.out;
}