feat: add balancer v2 executor

foundry/lib/balancer-labs/v2-interfaces/contracts/solidity-utils/helpers/IOptionalOnlyCaller.sol

@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+pragma solidity >=0.7.0 <0.9.0;
+
+/**
+ * @dev Interface for the OptionalOnlyCaller helper, used to opt in to a caller
+ * verification for a given address to methods that are otherwise callable by any address.
+ */
+interface IOptionalOnlyCaller {
+    /**
+     * @dev Emitted every time setOnlyCallerCheck is called.
+     */
+    event OnlyCallerOptIn(address user, bool enabled);
+
+    /**
+     * @dev Enables / disables verification mechanism for caller.
+     * @param enabled - True if caller verification shall be enabled, false otherwise.
+     */
+    function setOnlyCallerCheck(bool enabled) external;
+
+    function setOnlyCallerCheckWithSignature(
+        address user,
+        bool enabled,
+        bytes memory signature
+    ) external;
+
+    /**
+     * @dev Returns true if caller verification is enabled for the given user, false otherwise.
+     */
+    function isOnlyCallerEnabled(address user) external view returns (bool);
+}