PRE-1753: ERC4626 rounding audit feedback (#70)

* auto wrapper changes

* test fixes

* remove unnecessary import

* update makefile

Author: arora-anmol

Makefile

@@ -3,9 +3,9 @@
 DEPLOYER_ECDSA_PRIV_KEY=0xac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
 # public key - 0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266
 
-PREDICATE_HOOK_ADDRESS=0x3BD20e23e524a20dA67F73e65938aABd1C47E880
+PREDICATE_HOOK_ADDRESS=0x452e2E2CfcaC437d4E321226A3255d2cFc5c68A0
 SWAP_ROUTER_ADDRESS=0x8F2c925603c4ba055779475F14241E3c9ee7c1be
-AUTO_WRAPPER_HOOK_ADDRESS=0x3f39eC4911c77085a8E6b9d99C7EaA351d64e8C8
+AUTO_WRAPPER_HOOK_ADDRESS=0x75202124c8B7FAFBD66AB67F39CE01f69C0128c8
 POSM_ADDRESS=0xbD216513d74C8cf14cf4747E6AaA6420FF64ee9e
 # POLICY_ID=x-aleo-6a52de9724a6e8f2 // mainnet
 POLICY_ID=local-test-policy
@@ -81,16 +81,38 @@ create-pool-and-mint-liquidity:
 		--private-key ${DEPLOYER_ECDSA_PRIV_KEY} \
 		--broadcast -vvvv
 
-swap-usdc-for-usdl:
+swap-usdc-for-usdl-exact-in:
 	export NETWORK=${NETWORK} && \
+	export CASE=SWAP_USDC_FOR_USDL_EXACT_IN && \
 	export AUTO_WRAPPER_HOOK_ADDRESS=${AUTO_WRAPPER_HOOK_ADDRESS} && \
 	export SWAP_ROUTER_ADDRESS=${SWAP_ROUTER_ADDRESS} && \
-	forge script script/common/SwapUSDCForUSDL.s.sol \
+	forge script script/common/SwapScript.s.sol \
 		--via-ir \
 		--rpc-url ${RPC_URL} \
 		--private-key ${DEPLOYER_ECDSA_PRIV_KEY} \
 		--broadcast -vvvv
 
+swap-usdl-for-usdc-exact-in:
+	export NETWORK=${NETWORK} && \
+	export CASE=SWAP_USDL_FOR_USDC_EXACT_IN && \
+	export AUTO_WRAPPER_HOOK_ADDRESS=${AUTO_WRAPPER_HOOK_ADDRESS} && \
+	export SWAP_ROUTER_ADDRESS=${SWAP_ROUTER_ADDRESS} && \
+	forge script script/common/SwapScript.s.sol \
+		--via-ir \
+		--rpc-url ${RPC_URL} \
+		--private-key ${DEPLOYER_ECDSA_PRIV_KEY} \
+		--broadcast -vvvv
+
+swap-usdl-for-usdc-exact-out:
+	export NETWORK=${NETWORK} && \
+	export CASE=SWAP_USDL_FOR_USDC_EXACT_OUT && \
+	export AUTO_WRAPPER_HOOK_ADDRESS=${AUTO_WRAPPER_HOOK_ADDRESS} && \
+	export SWAP_ROUTER_ADDRESS=${SWAP_ROUTER_ADDRESS} && \
+	forge script script/common/SwapScript.s.sol \
+		--via-ir \
+		--rpc-url ${RPC_URL} \
+		--private-key ${DEPLOYER_ECDSA_PRIV_KEY} \
+		--broadcast -vvvv
 
 deploy-auto-wrapper:
 	export NETWORK=${NETWORK} && \

README.md

@@ -77,7 +77,7 @@ For testing with mainnet anvil fork:
 2. Run `make deploy-predicate-hook` to deploy standalone predicate hook contract. Update `PREDICATE_HOOK_ADDRESS` env variable in Makefile
 3. Run `make create-pool-and-mint-liquidity`. This deploys a V4 pool and mints necessary liquidity as well
 4. Run `make deploy-auto-wrapper` to deploy auto wrapper and create ghost pool. Update `AUTO_WRAPPER_HOOK_ADDRESS` env variable in Makefile.
-5. Run `make swap-usdc-for-usdl`. This will swap USDC for USDL on the ghost + liquidity pools that we just configured. (there's some more options available in the script that can be used).
+5. Run `make swap-usdc-for-usdl-exact-in`. This will swap USDC for USDL on the ghost + liquidity pools that we just configured. (there's some more options available in the script that can be used).
 
 *Note: Predicate signature validation is skipped as the predicate hook owner is added to an authorized owner allow-list during hook creation.*
 

script/common/SwapUSDCForUSDL.s.sol script/common/SwapScript.s.solscript/common/SwapUSDCForUSDL.s.sol renamed to script/common/SwapScript.s.sol

@@ -20,26 +20,49 @@ import {IPoolManager} from "@uniswap/v4-core/src/interfaces/IPoolManager.sol";
 import {V4SwapRouter} from "../../src/V4SwapRouter.sol";
 
 contract SwapScript is Script {
+    enum Case {
+        SWAP_USDC_FOR_USDL_EXACT_IN,
+        SWAP_USDL_FOR_USDC_EXACT_IN,
+        SWAP_USDL_FOR_USDC_EXACT_OUT
+    }
+
     uint24 lpFee = 0; // 0.30%
     int24 tickSpacing = 60;
     Currency private _currency0;
     Currency private _currency1;
     INetwork private _env;
     address private _autowrapperHookAddress;
     V4SwapRouter private _swapRouter;
+    string private _case;
 
     function _init() internal {
         bool networkExists = vm.envExists("NETWORK");
         bool autoWrapperHookAddress = vm.envExists("AUTO_WRAPPER_HOOK_ADDRESS");
         bool swapRouterAddressExists = vm.envExists("SWAP_ROUTER_ADDRESS");
+        bool caseExists = vm.envExists("CASE");
         require(
-            networkExists && autoWrapperHookAddress && swapRouterAddressExists,
+            networkExists && autoWrapperHookAddress && swapRouterAddressExists && caseExists,
             "All environment variables must be set if any are specified"
         );
         string memory _network = vm.envString("NETWORK");
         _env = new NetworkSelector().select(_network);
         _autowrapperHookAddress = vm.envAddress("AUTO_WRAPPER_HOOK_ADDRESS");
         _swapRouter = V4SwapRouter(vm.envAddress("SWAP_ROUTER_ADDRESS"));
+        _case = vm.envString("CASE");
+    }
+
+    function _stringToCase(
+        string memory _case
+    ) internal returns (Case) {
+        bytes32 _caseHash = keccak256(abi.encodePacked(_case));
+        if (_caseHash == keccak256(abi.encodePacked("SWAP_USDC_FOR_USDL_EXACT_IN"))) {
+            return Case.SWAP_USDC_FOR_USDL_EXACT_IN;
+        } else if (_caseHash == keccak256(abi.encodePacked("SWAP_USDL_FOR_USDC_EXACT_IN"))) {
+            return Case.SWAP_USDL_FOR_USDC_EXACT_IN;
+        } else if (_caseHash == keccak256(abi.encodePacked("SWAP_USDL_FOR_USDC_EXACT_OUT"))) {
+            return Case.SWAP_USDL_FOR_USDC_EXACT_OUT;
+        }
+        revert("Invalid case input");
     }
 
     function run() public {
@@ -54,9 +77,16 @@ contract SwapScript is Script {
         vm.label(address(0xf6f4A30EeF7cf51Ed4Ee1415fB3bFDAf3694B0d2), "SERVICEMANAGER_CONTRACT");
 
         _tokenApprovals();
-        swapUSDCForUSDLExactIn();
-        swapUSDLForUSDCExactIn();
-        // swapUSDLForUSDCExactOut();
+        Case _case = _stringToCase(_case);
+        if (_case == Case.SWAP_USDC_FOR_USDL_EXACT_IN) {
+            swapUSDCForUSDLExactIn();
+        } else if (_case == Case.SWAP_USDL_FOR_USDC_EXACT_IN) {
+            swapUSDLForUSDCExactIn();
+        } else if (_case == Case.SWAP_USDL_FOR_USDC_EXACT_OUT) {
+            swapUSDLForUSDCExactOut();
+        } else {
+            revert("Invalid case input");
+        }
     }
 
     function _tokenApprovals() internal {

src/AutoWrapper.sol

@@ -279,7 +279,7 @@ contract AutoWrapper is BaseHook, DeltaResolver, Ownable2Step {
             // Note: UniversalRouter sends USDL to the poolManager at start of swap
             // this route also uses USDL in auto wrapper contract for rounding error
             uint256 inputAmount =
-                isExactInput ? uint256(-params.amountSpecified) : uint256(getWrapInputRequired(uint256(-wUSDLDelta)));
+                isExactInput ? uint256(-params.amountSpecified) : wUSDL.previewMint(uint256(-wUSDLDelta));
             usdlBalanceBefore = IERC20(wUSDL.asset()).balanceOf(address(this));
             _take(Currency.wrap(wUSDL.asset()), address(this), inputAmount);
             usdlBalanceAfter = IERC20(wUSDL.asset()).balanceOf(address(this));
@@ -319,12 +319,35 @@ contract AutoWrapper is BaseHook, DeltaResolver, Ownable2Step {
     ) internal view returns (int256) {
         bool isExactInput = params.amountSpecified < 0;
         if (params.zeroForOne == baseCurrencyIsToken0) {
-            // USDC -> USDL pool
-            return isExactInput ? params.amountSpecified : getUnwrapInputRequired(uint256(params.amountSpecified));
+            // Ex. USDC/USDL pool -> USDL
+            // Ex. USDL/USDC pool -> USDL
+            return isExactInput
+                // USDC exact input:
+                // - Swap USDC (exact input, specified) for wUSDL in USDC/wUSDL pool.
+                // - Redeem wUSDL output shares for USDL assets.
+                ? params.amountSpecified
+                // USDL exact output:
+                // - Swap USDC (unspecified) for wUSDL (exact output, calculated) in USDC/wUSDL pool.
+                // - Redeem wUSDL output shares for USDL assets.
+                // We need to calculate the exact amount of wUSDL required
+                // which can be redeemed for the exact amount of output USDL amount specified.
+                // We therefore round up the required amount of wUSDL (`previewWithdraw`).
+                : int256(wUSDL.previewWithdraw({assets: uint256(params.amountSpecified)}));
         } else {
-            // USDL -> USDC ex. 5 USDL as output
-            // WUSDL/USDC pool
-            return isExactInput ? -(getUnwrapInputRequired(uint256(-params.amountSpecified))) : params.amountSpecified;
+            // Ex. USDL -> USDL/USDC pool
+            // Ex. USDL -> USDC/USDL pool
+            return isExactInput
+                // USDL exact input:
+                // - Deposit USDL (exact input, specified) for wUSDL shares (calculated).
+                // - Swap wUSDL (exact input, calculated) for USDC.
+                // We need to calculate the exact amount of wUSDL shares
+                // we will receive when depositing the exact amount of USDL amount specified.
+                // We therefore round down the estimated amount of wUSDL received (`previewDeposit`).
+                ? -int256(wUSDL.previewDeposit({assets: uint256(-params.amountSpecified)}))
+                // USDC exact output:
+                // - Deposit USDL (specified) assets for wUSDL shares.
+                // - Swap wUSDL shares for USDC.
+                : params.amountSpecified;
         }
     }
 
@@ -413,28 +436,6 @@ contract AutoWrapper is BaseHook, DeltaResolver, Ownable2Step {
         return wUSDL.redeem({shares: wUSDLAmount, receiver: address(this), owner: address(this)});
     }
 
-    /**
-     * @notice Calculates USDL required to obtain a desired amount of wUSDL
-     * @param wUSDLAmount The target amount of wUSDL needed
-     * @return wUSDL amount of USDL required
-     */
-    function getWrapInputRequired(
-        uint256 wUSDLAmount
-    ) public view returns (int256) {
-        return int256(wUSDL.previewMint(wUSDLAmount));
-    }
-
-    /**
-     * @notice Calculates wUSDL required to obtain a desired amount of USDL
-     * @param usdlAmount The target amount of USDL needed
-     * @return The amount of wUSDL required
-     */
-    function getUnwrapInputRequired(
-        uint256 usdlAmount
-    ) public view returns (int256) {
-        return int256(wUSDL.previewWithdraw(usdlAmount));
-    }
-
     /**
      * @notice Sets the router for the contract, only callable by the owner
      * @param _router The new router

test/AutoWrapperIntegration.t.sol

@@ -75,11 +75,12 @@ contract AutoWrapperIntegrationTest is Test, AutoWrapperSetup, OperatorTestPrep
     }
 
     function testSwapZeroForOneExactOutput() public permissionedOperators prepOperatorRegistration(true) {
+        // USDC -> USDL
         PoolKey memory key = getPoolKey();
         string memory taskId = "unique-identifier";
         uint256 amountSpecified = 1e18;
         PredicateMessage memory message =
-            getPredicateMessage(taskId, false, autoWrapper.getUnwrapInputRequired(amountSpecified));
+            getPredicateMessage(taskId, false, int256(autoWrapper.wUSDL().previewWithdraw(amountSpecified)));
         IV4Router.ExactOutputSingleParams memory swapParams = IV4Router.ExactOutputSingleParams({
             poolKey: key,
             zeroForOne: true,
@@ -112,7 +113,7 @@ contract AutoWrapperIntegrationTest is Test, AutoWrapperSetup, OperatorTestPrep
         PoolKey memory key = getPoolKey();
         uint256 amountSpecified = 1e18;
         PredicateMessage memory message =
-            getPredicateMessage(taskId, true, -autoWrapper.getUnwrapInputRequired(amountSpecified));
+            getPredicateMessage(taskId, true, -int256(autoWrapper.wUSDL().previewDeposit(amountSpecified)));
         IV4Router.ExactInputSingleParams memory swapParams = IV4Router.ExactInputSingleParams({
             poolKey: key,
             zeroForOne: false,
@@ -195,7 +196,7 @@ contract AutoWrapperIntegrationTest is Test, AutoWrapperSetup, OperatorTestPrep
         string memory taskId = "unique-identifier";
         uint256 amountSpecified = 1e18;
         PredicateMessage memory message =
-            getPredicateMessage(taskId, true, autoWrapper.getUnwrapInputRequired(amountSpecified));
+            getPredicateMessage(taskId, true, int256(autoWrapper.wUSDL().previewWithdraw(amountSpecified)));
 
         // change the taskId to an invalid one
         message.taskId = "invalid-task-id";