Make the value commitment randomness in the transaction generation random.

Author: murisi

contracts/test/ProtocolAdapterMock.t.sol

@@ -226,6 +226,7 @@ contract ProtocolAdapterMockVerifierTest is Test {
         Resource[2][MAX_RESOURCES] resources;
         uint256[MAX_RESOURCES] bijection;
         uint256 targetResourcesLen;
+        uint256[2][MAX_RESOURCES] valueCommitmentRandomness;
     }
 
     function commitment(Resource memory resource) internal pure returns (bytes32 hash) {
@@ -295,15 +296,20 @@ contract ProtocolAdapterMockVerifierTest is Test {
         }
         // Compute action tree tags and action tree root
         bytes32[] memory actionTreeTags = new bytes32[](2 * truncatedResources.length);
+        totalValueCommitmentRandomness = 0;
         for (uint256 i = 0; i < truncatedResources.length; ++i) {
             uint256 index = (i * 2);
 
             actionTreeTags[index] = nullifier(truncatedResources[i][0], 0);
             actionTreeTags[index + 1] = commitment(truncatedResources[i][1]);
+            // Adjust and accumulate the value randomness commitments
+            params.valueCommitmentRandomness[i][0] = bound(params.valueCommitmentRandomness[i][0], 1, SECP256K1_ORDER-1);
+            params.valueCommitmentRandomness[i][1] = bound(params.valueCommitmentRandomness[i][1], 1, SECP256K1_ORDER-1);
+            totalValueCommitmentRandomness = addmod(totalValueCommitmentRandomness, params.valueCommitmentRandomness[i][0], SECP256K1_ORDER);
+            totalValueCommitmentRandomness = addmod(totalValueCommitmentRandomness, params.valueCommitmentRandomness[i][1], SECP256K1_ORDER);
         }
         bytes32 actionTreeRoot = actionTreeTags.computeRoot();
         // Create logic and compliance verifier inputs
-        totalValueCommitmentRandomness = 0;
         for (uint256 i = 0; i < truncatedResources.length; i++) {
             Resource memory consumedResource = truncatedResources[i][0];
             Resource memory createdResource = truncatedResources[i][1];
@@ -339,9 +345,10 @@ contract ProtocolAdapterMockVerifierTest is Test {
                     kind: kind(consumedResource),
                     quantity: consumedResource.quantity,
                     consumed: true,
-                    valueCommitmentRandomness: 1
+                    valueCommitmentRandomness: params.valueCommitmentRandomness[i][0]
                 })
             );
+
             // Add the delta for the created resource
             unitDelta = Delta.add(
                 unitDelta,
@@ -351,11 +358,10 @@ contract ProtocolAdapterMockVerifierTest is Test {
                         kind: kind(createdResource),
                         quantity: createdResource.quantity,
                         consumed: false,
-                        valueCommitmentRandomness: 1
+                        valueCommitmentRandomness: params.valueCommitmentRandomness[i][1]
                     })
                 )
             );
-            totalValueCommitmentRandomness += 2;
             // Create the compliance verifier input
             Compliance.Instance memory instance = Compliance.Instance({
                 unitDeltaX: bytes32(unitDelta.x),
@@ -389,7 +395,7 @@ contract ProtocolAdapterMockVerifierTest is Test {
         for (uint256 i = 0; i < actions.length; i++) {
             uint256 valueCommitmentRandomness;
             (actions[i], valueCommitmentRandomness) = generateAction(params.actionParams[i]);
-            totalValueCommitmentRandomness += valueCommitmentRandomness;
+            totalValueCommitmentRandomness = addmod(totalValueCommitmentRandomness, valueCommitmentRandomness, SECP256K1_ORDER);
         }
         // Generate delta proof
         bytes memory proof = "";