feat: Implement BalancerV3Executor

Took 2 hours 32 minutes Took 8 seconds Took 13 minutes
2025-06-04 17:18:34 +01:00
parent cb105caecf
commit f34db52f09
5 changed files with 247 additions and 1 deletions
--- a/foundry/src/executors/BalancerV3Executor.sol
+++ b/foundry/src/executors/BalancerV3Executor.sol
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: BUSL-1.1
+pragma solidity ^0.8.26;
+
+import "@interfaces/IExecutor.sol";
+import {
+    IERC20,
+    SafeERC20
+} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import {IVault} from "@balancer-labs/v3-interfaces/contracts/vault/IVault.sol";
+import {
+    SwapKind,
+    VaultSwapParams
+} from "@balancer-labs/v3-interfaces/contracts/vault/VaultTypes.sol";
+import {RestrictTransferFrom} from "../RestrictTransferFrom.sol";
+
+error BalancerV3Executor__InvalidDataLength();
+error BalancerV3Executor__SenderIsNotVault(address sender);
+
+contract BalancerV3Executor is IExecutor, RestrictTransferFrom {
+    using SafeERC20 for IERC20;
+
+    IVault private constant VAULT =
+        IVault(0xbA1333333333a1BA1108E8412f11850A5C319bA9);
+
+    /**
+     * @notice Data for the swap hook.
+     * @param pool Address of the liquidity pool
+     * @param tokenIn Token to be swapped from
+     * @param tokenOut Token to be swapped to
+     * @param amountGiven Amount given based on kind of the swap
+     * @param transferType Type of transfer to be used for the token in
+     * @param receiver Address to receive the output token
+     */
+    struct SwapHookParams {
+        address pool;
+        IERC20 tokenIn;
+        IERC20 tokenOut;
+        uint256 amountGiven;
+        TransferType transferType;
+        address receiver;
+    }
+
+    constructor(address _permit2) RestrictTransferFrom(_permit2) {}
+
+    modifier onlyVault() {
+        if (msg.sender != address(VAULT)) {
+            revert BalancerV3Executor__SenderIsNotVault(msg.sender);
+        }
+        _;
+    }
+
+    // slither-disable-next-line locked-ether
+    function swap(uint256 givenAmount, bytes calldata data)
+        external
+        payable
+        returns (uint256 calculatedAmount)
+    {
+        (
+            IERC20 tokenIn,
+            IERC20 tokenOut,
+            address poolId,
+            TransferType transferType,
+            address receiver
+        ) = _decodeData(data);
+
+        calculatedAmount = abi.decode(
+            VAULT.unlock(
+                abi.encodeCall(
+                    BalancerV3Executor.swapHook,
+                    SwapHookParams({
+                        pool: poolId,
+                        tokenIn: tokenIn,
+                        tokenOut: tokenOut,
+                        amountGiven: givenAmount,
+                        transferType: transferType,
+                        receiver: receiver
+                    })
+                )
+            ),
+            (uint256)
+        );
+    }
+
+    /**
+     * @notice Hook to be called by the Balancer Vault.
+     * @param params Parameters for the swap hook.
+     * @return amountCalculated The amount calculated after the swap.
+     */
+    function swapHook(SwapHookParams calldata params)
+        external
+        onlyVault
+        returns (uint256 amountCalculated)
+    {
+        uint256 amountIn;
+        uint256 amountOut;
+        (amountCalculated, amountIn, amountOut) = VAULT.swap(
+            VaultSwapParams({
+                kind: SwapKind.EXACT_IN,
+                pool: params.pool,
+                tokenIn: params.tokenIn,
+                tokenOut: params.tokenOut,
+                amountGivenRaw: params.amountGiven,
+                limitRaw: 0,
+                userData: ""
+            })
+        );
+
+        _transfer(
+            address(VAULT),
+            params.transferType,
+            address(params.tokenIn),
+            amountIn
+        );
+        // slither-disable-next-line unused-return
+        VAULT.settle(params.tokenIn, amountIn);
+        VAULT.sendTo(params.tokenOut, params.receiver, amountOut);
+
+        return amountCalculated;
+    }
+
+    function _decodeData(bytes calldata data)
+        internal
+        pure
+        returns (
+            IERC20 tokenIn,
+            IERC20 tokenOut,
+            address poolId,
+            TransferType transferType,
+            address receiver
+        )
+    {
+        if (data.length != 81) {
+            revert BalancerV3Executor__InvalidDataLength();
+        }
+
+        tokenIn = IERC20(address(bytes20(data[0:20])));
+        tokenOut = IERC20(address(bytes20(data[20:40])));
+        poolId = address(bytes20(data[40:60]));
+        transferType = TransferType(uint8(data[60]));
+        receiver = address(bytes20(data[61:81]));
+    }
+}