From ccffe671054676b65a5d7f3434eb75b3237ff3dc Mon Sep 17 00:00:00 2001
From: Dan Finlay <dan@danfinlay.com>
Date: Sun, 21 Aug 2022 22:26:03 -0700
Subject: [PATCH 01/33] Add _msgSender() trick

Fixes #132

Enables MetaTransaction facets and [Delegatable](https://github.com/delegatable/delegatable-sol/blob/main/contracts/diamond/README.md).
---
 contracts/access/ownable/OwnableInternal.sol  | 26 ++++++++--
 contracts/security/PausableInternal.sol       | 24 +++++++++-
 contracts/token/ERC1155/base/ERC1155Base.sol  | 14 +++---
 .../ERC1155/base/ERC1155BaseInternal.sol      | 47 +++++++++++++++----
 contracts/token/ERC20/base/ERC20Base.sol      |  4 +-
 .../token/ERC20/base/ERC20BaseInternal.sol    | 24 +++++++++-
 contracts/token/ERC721/base/ERC721Base.sol    | 12 ++---
 .../token/ERC721/base/ERC721BaseInternal.sol  | 22 ++++++++-
 8 files changed, 140 insertions(+), 33 deletions(-)

diff --git a/contracts/access/ownable/OwnableInternal.sol b/contracts/access/ownable/OwnableInternal.sol
index 49366e812..1b3bca8a6 100644
--- a/contracts/access/ownable/OwnableInternal.sol
+++ b/contracts/access/ownable/OwnableInternal.sol
@@ -12,13 +12,13 @@ abstract contract OwnableInternal is IOwnableInternal {
     using OwnableStorage for OwnableStorage.Layout;
 
     modifier onlyOwner() {
-        require(msg.sender == _owner(), 'Ownable: sender must be owner');
+        require(_msgSender() == _owner(), 'Ownable: sender must be owner');
         _;
     }
 
     modifier onlyTransitiveOwner() {
         require(
-            msg.sender == _transitiveOwner(),
+            _msgSender() == _transitiveOwner(),
             'Ownable: sender must be transitive owner'
         );
         _;
@@ -44,6 +44,26 @@ abstract contract OwnableInternal is IOwnableInternal {
 
     function _transferOwnership(address account) internal virtual {
         OwnableStorage.layout().setOwner(account);
-        emit OwnershipTransferred(msg.sender, account);
+        emit OwnershipTransferred(_msgSender(), account);
+    }
+
+    /*
+     * @notice Overrides the msgSender to enable delegation message signing.
+     * @returns address - The account whose authority is being acted on.
+     */
+    function _msgSender() internal view virtual returns (address sender) {
+        if (msg.sender == address(this)) {
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
+            assembly {
+                sender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            sender = msg.sender;
+        }
+        return sender;
     }
 }
diff --git a/contracts/security/PausableInternal.sol b/contracts/security/PausableInternal.sol
index 3aec4f662..50e9077b9 100644
--- a/contracts/security/PausableInternal.sol
+++ b/contracts/security/PausableInternal.sol
@@ -37,7 +37,7 @@ abstract contract PausableInternal {
      */
     function _pause() internal virtual whenNotPaused {
         PausableStorage.layout().paused = true;
-        emit Paused(msg.sender);
+        emit Paused(_msgSender());
     }
 
     /**
@@ -45,6 +45,26 @@ abstract contract PausableInternal {
      */
     function _unpause() internal virtual whenPaused {
         PausableStorage.layout().paused = false;
-        emit Unpaused(msg.sender);
+        emit Unpaused(_msgSender());
+    }
+
+    /*
+     * @notice Overrides the msgSender to enable delegation message signing.
+     * @returns address - The account whose authority is being acted on.
+     */
+    function _msgSender() internal view virtual returns (address sender) {
+        if (msg.sender == address(this)) {
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
+            assembly {
+                sender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            sender = msg.sender;
+        }
+        return sender;
     }
 }
diff --git a/contracts/token/ERC1155/base/ERC1155Base.sol b/contracts/token/ERC1155/base/ERC1155Base.sol
index 1df879a1f..7356db720 100644
--- a/contracts/token/ERC1155/base/ERC1155Base.sol
+++ b/contracts/token/ERC1155/base/ERC1155Base.sol
@@ -73,13 +73,13 @@ abstract contract ERC1155Base is IERC1155Base, ERC1155BaseInternal {
      */
     function setApprovalForAll(address operator, bool status) public virtual {
         require(
-            msg.sender != operator,
+            _msgSender() != operator,
             'ERC1155: setting approval status for self'
         );
-        ERC1155BaseStorage.layout().operatorApprovals[msg.sender][
+        ERC1155BaseStorage.layout().operatorApprovals[_msgSender()][
             operator
         ] = status;
-        emit ApprovalForAll(msg.sender, operator, status);
+        emit ApprovalForAll(_msgSender(), operator, status);
     }
 
     /**
@@ -93,10 +93,10 @@ abstract contract ERC1155Base is IERC1155Base, ERC1155BaseInternal {
         bytes memory data
     ) public virtual {
         require(
-            from == msg.sender || isApprovedForAll(from, msg.sender),
+            from == _msgSender() || isApprovedForAll(from, _msgSender()),
             'ERC1155: caller is not owner nor approved'
         );
-        _safeTransfer(msg.sender, from, to, id, amount, data);
+        _safeTransfer(_msgSender(), from, to, id, amount, data);
     }
 
     /**
@@ -110,9 +110,9 @@ abstract contract ERC1155Base is IERC1155Base, ERC1155BaseInternal {
         bytes memory data
     ) public virtual {
         require(
-            from == msg.sender || isApprovedForAll(from, msg.sender),
+            from == _msgSender() || isApprovedForAll(from, _msgSender()),
             'ERC1155: caller is not owner nor approved'
         );
-        _safeTransferBatch(msg.sender, from, to, ids, amounts, data);
+        _safeTransferBatch(_msgSender(), from, to, ids, amounts, data);
     }
 }
diff --git a/contracts/token/ERC1155/base/ERC1155BaseInternal.sol b/contracts/token/ERC1155/base/ERC1155BaseInternal.sol
index 639442757..71e9bee02 100644
--- a/contracts/token/ERC1155/base/ERC1155BaseInternal.sol
+++ b/contracts/token/ERC1155/base/ERC1155BaseInternal.sol
@@ -50,7 +50,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         require(account != address(0), 'ERC1155: mint to the zero address');
 
         _beforeTokenTransfer(
-            msg.sender,
+            _msgSender(),
             address(0),
             account,
             _asSingletonArray(id),
@@ -60,7 +60,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
 
         ERC1155BaseStorage.layout().balances[id][account] += amount;
 
-        emit TransferSingle(msg.sender, address(0), account, id, amount);
+        emit TransferSingle(_msgSender(), address(0), account, id, amount);
     }
 
     /**
@@ -79,7 +79,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         _mint(account, id, amount, data);
 
         _doSafeTransferAcceptanceCheck(
-            msg.sender,
+            _msgSender(),
             address(0),
             account,
             id,
@@ -109,7 +109,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         );
 
         _beforeTokenTransfer(
-            msg.sender,
+            _msgSender(),
             address(0),
             account,
             ids,
@@ -127,7 +127,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
             }
         }
 
-        emit TransferBatch(msg.sender, address(0), account, ids, amounts);
+        emit TransferBatch(_msgSender(), address(0), account, ids, amounts);
     }
 
     /**
@@ -146,7 +146,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         _mintBatch(account, ids, amounts, data);
 
         _doSafeBatchTransferAcceptanceCheck(
-            msg.sender,
+            _msgSender(),
             address(0),
             account,
             ids,
@@ -169,7 +169,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         require(account != address(0), 'ERC1155: burn from the zero address');
 
         _beforeTokenTransfer(
-            msg.sender,
+            _msgSender(),
             account,
             address(0),
             _asSingletonArray(id),
@@ -189,7 +189,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
             balances[account] -= amount;
         }
 
-        emit TransferSingle(msg.sender, account, address(0), id, amount);
+        emit TransferSingle(_msgSender(), account, address(0), id, amount);
     }
 
     /**
@@ -209,7 +209,14 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
             'ERC1155: ids and amounts length mismatch'
         );
 
-        _beforeTokenTransfer(msg.sender, account, address(0), ids, amounts, '');
+        _beforeTokenTransfer(
+            _msgSender(),
+            account,
+            address(0),
+            ids,
+            amounts,
+            ''
+        );
 
         mapping(uint256 => mapping(address => uint256))
             storage balances = ERC1155BaseStorage.layout().balances;
@@ -225,7 +232,7 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
             }
         }
 
-        emit TransferBatch(msg.sender, account, address(0), ids, amounts);
+        emit TransferBatch(_msgSender(), account, address(0), ids, amounts);
     }
 
     /**
@@ -504,4 +511,24 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         uint256[] memory amounts,
         bytes memory data
     ) internal virtual {}
+
+    /*
+     * @notice Overrides the msgSender to enable delegation message signing.
+     * @returns address - The account whose authority is being acted on.
+     */
+    function _msgSender() internal view virtual returns (address sender) {
+        if (msg.sender == address(this)) {
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
+            assembly {
+                sender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            sender = msg.sender;
+        }
+        return sender;
+    }
 }
diff --git a/contracts/token/ERC20/base/ERC20Base.sol b/contracts/token/ERC20/base/ERC20Base.sol
index 35d003289..b17d88cbc 100644
--- a/contracts/token/ERC20/base/ERC20Base.sol
+++ b/contracts/token/ERC20/base/ERC20Base.sol
@@ -45,7 +45,7 @@ abstract contract ERC20Base is IERC20Base, ERC20BaseInternal {
         virtual
         returns (bool)
     {
-        return _approve(msg.sender, spender, amount);
+        return _approve(_msgSender(), spender, amount);
     }
 
     /**
@@ -56,7 +56,7 @@ abstract contract ERC20Base is IERC20Base, ERC20BaseInternal {
         virtual
         returns (bool)
     {
-        return _transfer(msg.sender, recipient, amount);
+        return _transfer(_msgSender(), recipient, amount);
     }
 
     /**
diff --git a/contracts/token/ERC20/base/ERC20BaseInternal.sol b/contracts/token/ERC20/base/ERC20BaseInternal.sol
index e3aace4d3..0f38c5ce3 100644
--- a/contracts/token/ERC20/base/ERC20BaseInternal.sol
+++ b/contracts/token/ERC20/base/ERC20BaseInternal.sol
@@ -151,7 +151,7 @@ abstract contract ERC20BaseInternal is IERC20BaseInternal {
         address recipient,
         uint256 amount
     ) internal virtual returns (bool) {
-        uint256 currentAllowance = _allowance(holder, msg.sender);
+        uint256 currentAllowance = _allowance(holder, _msgSender());
 
         require(
             currentAllowance >= amount,
@@ -159,7 +159,7 @@ abstract contract ERC20BaseInternal is IERC20BaseInternal {
         );
 
         unchecked {
-            _approve(holder, msg.sender, currentAllowance - amount);
+            _approve(holder, _msgSender(), currentAllowance - amount);
         }
 
         _transfer(holder, recipient, amount);
@@ -179,4 +179,24 @@ abstract contract ERC20BaseInternal is IERC20BaseInternal {
         address to,
         uint256 amount
     ) internal virtual {}
+
+    /*
+     * @notice Overrides the msgSender to enable delegation message signing.
+     * @returns address - The account whose authority is being acted on.
+     */
+    function _msgSender() internal view virtual returns (address sender) {
+        if (msg.sender == address(this)) {
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
+            assembly {
+                sender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            sender = msg.sender;
+        }
+        return sender;
+    }
 }
diff --git a/contracts/token/ERC721/base/ERC721Base.sol b/contracts/token/ERC721/base/ERC721Base.sol
index 22fe73421..343c61c98 100644
--- a/contracts/token/ERC721/base/ERC721Base.sol
+++ b/contracts/token/ERC721/base/ERC721Base.sol
@@ -61,7 +61,7 @@ abstract contract ERC721Base is IERC721Base, ERC721BaseInternal {
     ) public payable {
         _handleTransferMessageValue(from, to, tokenId, msg.value);
         require(
-            _isApprovedOrOwner(msg.sender, tokenId),
+            _isApprovedOrOwner(_msgSender(), tokenId),
             'ERC721: transfer caller is not owner or approved'
         );
         _transfer(from, to, tokenId);
@@ -89,7 +89,7 @@ abstract contract ERC721Base is IERC721Base, ERC721BaseInternal {
     ) public payable {
         _handleTransferMessageValue(from, to, tokenId, msg.value);
         require(
-            _isApprovedOrOwner(msg.sender, tokenId),
+            _isApprovedOrOwner(_msgSender(), tokenId),
             'ERC721: transfer caller is not owner or approved'
         );
         _safeTransfer(from, to, tokenId, data);
@@ -103,7 +103,7 @@ abstract contract ERC721Base is IERC721Base, ERC721BaseInternal {
         address owner = ownerOf(tokenId);
         require(operator != owner, 'ERC721: approval to current owner');
         require(
-            msg.sender == owner || isApprovedForAll(owner, msg.sender),
+            _msgSender() == owner || isApprovedForAll(owner, _msgSender()),
             'ERC721: approve caller is not owner nor approved for all'
         );
         _approve(operator, tokenId);
@@ -113,10 +113,10 @@ abstract contract ERC721Base is IERC721Base, ERC721BaseInternal {
      * @inheritdoc IERC721
      */
     function setApprovalForAll(address operator, bool status) public {
-        require(operator != msg.sender, 'ERC721: approve to caller');
-        ERC721BaseStorage.layout().operatorApprovals[msg.sender][
+        require(operator != _msgSender(), 'ERC721: approve to caller');
+        ERC721BaseStorage.layout().operatorApprovals[_msgSender()][
             operator
         ] = status;
-        emit ApprovalForAll(msg.sender, operator, status);
+        emit ApprovalForAll(_msgSender(), operator, status);
     }
 }
diff --git a/contracts/token/ERC721/base/ERC721BaseInternal.sol b/contracts/token/ERC721/base/ERC721BaseInternal.sol
index 8c1d7b624..810ed08d6 100644
--- a/contracts/token/ERC721/base/ERC721BaseInternal.sol
+++ b/contracts/token/ERC721/base/ERC721BaseInternal.sol
@@ -179,7 +179,7 @@ abstract contract ERC721BaseInternal is IERC721Internal {
         bytes memory returnData = to.functionCall(
             abi.encodeWithSelector(
                 IERC721Receiver(to).onERC721Received.selector,
-                msg.sender,
+                _msgSender(),
                 from,
                 tokenId,
                 data
@@ -229,4 +229,24 @@ abstract contract ERC721BaseInternal is IERC721Internal {
         address to,
         uint256 tokenId
     ) internal virtual {}
+
+    /*
+     * @notice Overrides the msgSender to enable delegation message signing.
+     * @returns address - The account whose authority is being acted on.
+     */
+    function _msgSender() internal view virtual returns (address sender) {
+        if (msg.sender == address(this)) {
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
+            assembly {
+                sender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            sender = msg.sender;
+        }
+        return sender;
+    }
 }

From a0b566ebeb3b7d4998dd4349ae822e72c3318700 Mon Sep 17 00:00:00 2001
From: Dan Finlay <dan@danfinlay.com>
Date: Thu, 25 Aug 2022 18:44:44 -0700
Subject: [PATCH 02/33] Move msgSender trick to utils file

---
 contracts/access/ownable/OwnableInternal.sol  | 23 ++-------------
 contracts/security/PausableInternal.sol       | 23 ++-------------
 .../ERC1155/base/ERC1155BaseInternal.sol      | 23 ++-------------
 .../token/ERC20/base/ERC20BaseInternal.sol    | 23 ++-------------
 .../token/ERC721/base/ERC721BaseInternal.sol  | 23 ++-------------
 contracts/utils/MsgSenderTrick.sol            | 28 +++++++++++++++++++
 6 files changed, 38 insertions(+), 105 deletions(-)
 create mode 100644 contracts/utils/MsgSenderTrick.sol

diff --git a/contracts/access/ownable/OwnableInternal.sol b/contracts/access/ownable/OwnableInternal.sol
index 1b3bca8a6..b35966610 100644
--- a/contracts/access/ownable/OwnableInternal.sol
+++ b/contracts/access/ownable/OwnableInternal.sol
@@ -6,8 +6,9 @@ import { AddressUtils } from '../../utils/AddressUtils.sol';
 import { IERC173 } from '../IERC173.sol';
 import { IOwnableInternal } from './IOwnableInternal.sol';
 import { OwnableStorage } from './OwnableStorage.sol';
+import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
 
-abstract contract OwnableInternal is IOwnableInternal {
+abstract contract OwnableInternal is IOwnableInternal, MsgSenderTrick {
     using AddressUtils for address;
     using OwnableStorage for OwnableStorage.Layout;
 
@@ -46,24 +47,4 @@ abstract contract OwnableInternal is IOwnableInternal {
         OwnableStorage.layout().setOwner(account);
         emit OwnershipTransferred(_msgSender(), account);
     }
-
-    /*
-     * @notice Overrides the msgSender to enable delegation message signing.
-     * @returns address - The account whose authority is being acted on.
-     */
-    function _msgSender() internal view virtual returns (address sender) {
-        if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-            assembly {
-                sender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
-        } else {
-            sender = msg.sender;
-        }
-        return sender;
-    }
 }
diff --git a/contracts/security/PausableInternal.sol b/contracts/security/PausableInternal.sol
index 50e9077b9..d696e43cb 100644
--- a/contracts/security/PausableInternal.sol
+++ b/contracts/security/PausableInternal.sol
@@ -3,11 +3,12 @@
 pragma solidity ^0.8.8;
 
 import { PausableStorage } from './PausableStorage.sol';
+import { MsgSenderTrick } from '../utils/MsgSenderTrick.sol';
 
 /**
  * @title Internal functions for Pausable security control module.
  */
-abstract contract PausableInternal {
+abstract contract PausableInternal is MsgSenderTrick {
     using PausableStorage for PausableStorage.Layout;
 
     event Paused(address account);
@@ -47,24 +48,4 @@ abstract contract PausableInternal {
         PausableStorage.layout().paused = false;
         emit Unpaused(_msgSender());
     }
-
-    /*
-     * @notice Overrides the msgSender to enable delegation message signing.
-     * @returns address - The account whose authority is being acted on.
-     */
-    function _msgSender() internal view virtual returns (address sender) {
-        if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-            assembly {
-                sender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
-        } else {
-            sender = msg.sender;
-        }
-        return sender;
-    }
 }
diff --git a/contracts/token/ERC1155/base/ERC1155BaseInternal.sol b/contracts/token/ERC1155/base/ERC1155BaseInternal.sol
index 71e9bee02..4193809ca 100644
--- a/contracts/token/ERC1155/base/ERC1155BaseInternal.sol
+++ b/contracts/token/ERC1155/base/ERC1155BaseInternal.sol
@@ -6,12 +6,13 @@ import { AddressUtils } from '../../../utils/AddressUtils.sol';
 import { IERC1155Internal } from '../IERC1155Internal.sol';
 import { IERC1155Receiver } from '../IERC1155Receiver.sol';
 import { ERC1155BaseStorage } from './ERC1155BaseStorage.sol';
+import { MsgSenderTrick } from '../../../utils/MsgSenderTrick.sol';
 
 /**
  * @title Base ERC1155 internal functions
  * @dev derived from https://github.com/OpenZeppelin/openzeppelin-contracts/ (MIT license)
  */
-abstract contract ERC1155BaseInternal is IERC1155Internal {
+abstract contract ERC1155BaseInternal is IERC1155Internal, MsgSenderTrick {
     using AddressUtils for address;
 
     /**
@@ -511,24 +512,4 @@ abstract contract ERC1155BaseInternal is IERC1155Internal {
         uint256[] memory amounts,
         bytes memory data
     ) internal virtual {}
-
-    /*
-     * @notice Overrides the msgSender to enable delegation message signing.
-     * @returns address - The account whose authority is being acted on.
-     */
-    function _msgSender() internal view virtual returns (address sender) {
-        if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-            assembly {
-                sender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
-        } else {
-            sender = msg.sender;
-        }
-        return sender;
-    }
 }
diff --git a/contracts/token/ERC20/base/ERC20BaseInternal.sol b/contracts/token/ERC20/base/ERC20BaseInternal.sol
index 0f38c5ce3..c64527bd8 100644
--- a/contracts/token/ERC20/base/ERC20BaseInternal.sol
+++ b/contracts/token/ERC20/base/ERC20BaseInternal.sol
@@ -4,11 +4,12 @@ pragma solidity ^0.8.8;
 
 import { IERC20BaseInternal } from './IERC20BaseInternal.sol';
 import { ERC20BaseStorage } from './ERC20BaseStorage.sol';
+import { MsgSenderTrick } from '../../../utils/MsgSenderTrick.sol';
 
 /**
  * @title Base ERC20 internal functions, excluding optional extensions
  */
-abstract contract ERC20BaseInternal is IERC20BaseInternal {
+abstract contract ERC20BaseInternal is IERC20BaseInternal, MsgSenderTrick {
     /**
      * @notice query the total minted token supply
      * @return token supply
@@ -179,24 +180,4 @@ abstract contract ERC20BaseInternal is IERC20BaseInternal {
         address to,
         uint256 amount
     ) internal virtual {}
-
-    /*
-     * @notice Overrides the msgSender to enable delegation message signing.
-     * @returns address - The account whose authority is being acted on.
-     */
-    function _msgSender() internal view virtual returns (address sender) {
-        if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-            assembly {
-                sender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
-        } else {
-            sender = msg.sender;
-        }
-        return sender;
-    }
 }
diff --git a/contracts/token/ERC721/base/ERC721BaseInternal.sol b/contracts/token/ERC721/base/ERC721BaseInternal.sol
index 810ed08d6..868fc4f17 100644
--- a/contracts/token/ERC721/base/ERC721BaseInternal.sol
+++ b/contracts/token/ERC721/base/ERC721BaseInternal.sol
@@ -8,11 +8,12 @@ import { EnumerableSet } from '../../../utils/EnumerableSet.sol';
 import { IERC721Internal } from '../IERC721Internal.sol';
 import { IERC721Receiver } from '../IERC721Receiver.sol';
 import { ERC721BaseStorage } from './ERC721BaseStorage.sol';
+import { MsgSenderTrick } from '../../../utils/MsgSenderTrick.sol';
 
 /**
  * @title Base ERC721 internal functions
  */
-abstract contract ERC721BaseInternal is IERC721Internal {
+abstract contract ERC721BaseInternal is IERC721Internal, MsgSenderTrick {
     using ERC721BaseStorage for ERC721BaseStorage.Layout;
     using AddressUtils for address;
     using EnumerableMap for EnumerableMap.UintToAddressMap;
@@ -229,24 +230,4 @@ abstract contract ERC721BaseInternal is IERC721Internal {
         address to,
         uint256 tokenId
     ) internal virtual {}
-
-    /*
-     * @notice Overrides the msgSender to enable delegation message signing.
-     * @returns address - The account whose authority is being acted on.
-     */
-    function _msgSender() internal view virtual returns (address sender) {
-        if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-            assembly {
-                sender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
-        } else {
-            sender = msg.sender;
-        }
-        return sender;
-    }
 }
diff --git a/contracts/utils/MsgSenderTrick.sol b/contracts/utils/MsgSenderTrick.sol
new file mode 100644
index 000000000..e9911248e
--- /dev/null
+++ b/contracts/utils/MsgSenderTrick.sol
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.8;
+
+/**
+ * @title Utility contract for supporting alternative authorization schemes
+ */
+abstract contract MsgSenderTrick {
+    /*
+     * @notice Overrides the msgSender to enable delegation message signing.
+     * @returns address - The account whose authority is being acted on.
+     */
+    function _msgSender() internal view virtual returns (address sender) {
+        if (msg.sender == address(this)) {
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
+            assembly {
+                sender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            sender = msg.sender;
+        }
+        return sender;
+    }
+}

From 3e876b3c35cf9d99761468bbeee19647966d1c3d Mon Sep 17 00:00:00 2001
From: Dan Finlay <dan@danfinlay.com>
Date: Thu, 25 Aug 2022 19:25:00 -0700
Subject: [PATCH 03/33] Bring in the better documented version of _msgSender

---
 contracts/utils/MsgSenderTrick.sol | 44 ++++++++++++++++++++++++------
 1 file changed, 35 insertions(+), 9 deletions(-)

diff --git a/contracts/utils/MsgSenderTrick.sol b/contracts/utils/MsgSenderTrick.sol
index e9911248e..bf84eabe6 100644
--- a/contracts/utils/MsgSenderTrick.sol
+++ b/contracts/utils/MsgSenderTrick.sol
@@ -7,22 +7,48 @@ pragma solidity ^0.8.8;
  */
 abstract contract MsgSenderTrick {
     /*
-     * @notice Overrides the msgSender to enable delegation message signing.
+     * @notice Returns the intended sender of a message. Either msg.sender or the address of the authorizing signer.
+     *         Enables MetaTransactions, since the sender doesn't need to be the tx.origin or even the msg.sender.
      * @returns address - The account whose authority is being acted on.
+     * and the end-user for GSN relayed calls (where msg.sender is actually `RelayHub`).
+     *
+     * IMPORTANT: Contracts derived from {GSNRecipient} should never use `msg.sender`, and use {_msgSender} instead.
      */
     function _msgSender() internal view virtual returns (address sender) {
         if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-            assembly {
-                sender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
+            return _getRelayedCallSender();
         } else {
             sender = msg.sender;
         }
         return sender;
     }
+
+    function _getRelayedCallSender()
+        private
+        pure
+        returns (address payable result)
+    {
+        // We need to read 20 bytes (an address) located at array index msg.data.length - 20. In memory, the array
+        // is prefixed with a 32-byte length value, so we first add 32 to get the memory read index. However, doing
+        // so would leave the address in the upper 20 bytes of the 32-byte word, which is inconvenient and would
+        // require bit shifting. We therefore subtract 12 from the read index so the address lands on the lower 20
+        // bytes. This can always be done due to the 32-byte prefix.
+
+        // The final memory read index is msg.data.length - 20 + 32 - 12 = msg.data.length. Using inline assembly is the
+        // easiest/most-efficient way to perform this operation.
+
+        // These fields are not accessible from assembly
+        bytes memory array = msg.data;
+        uint256 index = msg.data.length;
+
+        // solhint-disable-next-line no-inline-assembly
+        assembly {
+            // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
+            result := and(
+                mload(add(array, index)),
+                0xffffffffffffffffffffffffffffffffffffffff
+            )
+        }
+        return result;
+    }
 }

From bbb0b616482c79a2145f490ee4895a2afb3ad048 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Mon, 17 Mar 2025 00:54:06 -0600
Subject: [PATCH 04/33] fix pragma statement

---
 contracts/utils/MsgSenderTrick.sol | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contracts/utils/MsgSenderTrick.sol b/contracts/utils/MsgSenderTrick.sol
index bf84eabe6..19fec0aa2 100644
--- a/contracts/utils/MsgSenderTrick.sol
+++ b/contracts/utils/MsgSenderTrick.sol
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity ^0.8.8;
+pragma solidity ^0.8.20;
 
 /**
  * @title Utility contract for supporting alternative authorization schemes

From 63366d272affbf57509168a563102346ecae10b6 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Mon, 17 Mar 2025 01:08:25 -0600
Subject: [PATCH 05/33] update MsgSenderTrick to comply with layers pattern

---
 contracts/access/access_control/_AccessControl.sol        | 4 ++--
 contracts/access/access_control/_IAccessControl.sol       | 4 +++-
 contracts/access/ownable/_IOwnable.sol                    | 3 ++-
 contracts/access/ownable/_Ownable.sol                     | 4 ++--
 .../security/partially_pausable/_IPartiallyPausable.sol   | 4 +++-
 .../security/partially_pausable/_PartiallyPausable.sol    | 4 ++--
 contracts/security/pausable/_IPausable.sol                | 4 +++-
 contracts/security/pausable/_Pausable.sol                 | 4 ++--
 contracts/token/fungible/_FungibleToken.sol               | 4 ++--
 contracts/token/fungible/_IFungibleToken.sol              | 3 ++-
 contracts/token/multi/_IMultiToken.sol                    | 3 ++-
 contracts/token/multi/_MultiToken.sol                     | 8 ++++++--
 contracts/token/non_fungible/_INonFungibleToken.sol       | 3 ++-
 contracts/token/non_fungible/_NonFungibleToken.sol        | 4 ++--
 contracts/utils/_IMsgSenderTrick.sol                      | 5 +++++
 .../utils/{MsgSenderTrick.sol => _MsgSenderTrick.sol}     | 3 ++-
 16 files changed, 42 insertions(+), 22 deletions(-)
 create mode 100644 contracts/utils/_IMsgSenderTrick.sol
 rename contracts/utils/{MsgSenderTrick.sol => _MsgSenderTrick.sol} (95%)

diff --git a/contracts/access/access_control/_AccessControl.sol b/contracts/access/access_control/_AccessControl.sol
index 9b018d2b7..98b3d2822 100644
--- a/contracts/access/access_control/_AccessControl.sol
+++ b/contracts/access/access_control/_AccessControl.sol
@@ -6,14 +6,14 @@ import { EnumerableSet } from '../../data/EnumerableSet.sol';
 import { AccessControlStorage } from '../../storage/AccessControlStorage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
 import { UintUtils } from '../../utils/UintUtils.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _IAccessControl } from './_IAccessControl.sol';
 
 /**
  * @title Role-based access control system
  * @dev derived from https://github.com/OpenZeppelin/openzeppelin-contracts (MIT license)
  */
-abstract contract _AccessControl is _IAccessControl, MsgSenderTrick {
+abstract contract _AccessControl is _IAccessControl, _MsgSenderTrick {
     using AddressUtils for address;
     using EnumerableSet for EnumerableSet.AddressSet;
     using UintUtils for uint256;
diff --git a/contracts/access/access_control/_IAccessControl.sol b/contracts/access/access_control/_IAccessControl.sol
index 4dd871cb7..53216fdf6 100644
--- a/contracts/access/access_control/_IAccessControl.sol
+++ b/contracts/access/access_control/_IAccessControl.sol
@@ -2,10 +2,12 @@
 
 pragma solidity ^0.8.20;
 
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+
 /**
  * @title Partial AccessControl interface needed by internal functions
  */
-interface _IAccessControl {
+interface _IAccessControl is _IMsgSenderTrick {
     event RoleAdminChanged(
         bytes32 indexed role,
         bytes32 indexed previousAdminRole,
diff --git a/contracts/access/ownable/_IOwnable.sol b/contracts/access/ownable/_IOwnable.sol
index 1fda6acb8..ddf13984e 100644
--- a/contracts/access/ownable/_IOwnable.sol
+++ b/contracts/access/ownable/_IOwnable.sol
@@ -3,8 +3,9 @@
 pragma solidity ^0.8.20;
 
 import { _IERC173 } from '../../interfaces/_IERC173.sol';
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
 
-interface _IOwnable is _IERC173 {
+interface _IOwnable is _IERC173, _IMsgSenderTrick {
     error Ownable__NotOwner();
     error Ownable__NotTransitiveOwner();
 }
diff --git a/contracts/access/ownable/_Ownable.sol b/contracts/access/ownable/_Ownable.sol
index e433aba06..178fb772f 100644
--- a/contracts/access/ownable/_Ownable.sol
+++ b/contracts/access/ownable/_Ownable.sol
@@ -5,10 +5,10 @@ pragma solidity ^0.8.20;
 import { IERC173 } from '../../interfaces/IERC173.sol';
 import { ERC173Storage } from '../../storage/ERC173Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _IOwnable } from './_IOwnable.sol';
 
-abstract contract _Ownable is _IOwnable, MsgSenderTrick {
+abstract contract _Ownable is _IOwnable, _MsgSenderTrick {
     using AddressUtils for address;
 
     modifier onlyOwner() {
diff --git a/contracts/security/partially_pausable/_IPartiallyPausable.sol b/contracts/security/partially_pausable/_IPartiallyPausable.sol
index 637c069dd..c6eedb2f9 100644
--- a/contracts/security/partially_pausable/_IPartiallyPausable.sol
+++ b/contracts/security/partially_pausable/_IPartiallyPausable.sol
@@ -2,7 +2,9 @@
 
 pragma solidity ^0.8.20;
 
-interface _IPartiallyPausable {
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+
+interface _IPartiallyPausable is _IMsgSenderTrick {
     error PartiallyPausable__PartiallyPaused();
     error PartiallyPausable__NotPartiallyPaused();
 
diff --git a/contracts/security/partially_pausable/_PartiallyPausable.sol b/contracts/security/partially_pausable/_PartiallyPausable.sol
index 025c8dbf5..d610f497b 100644
--- a/contracts/security/partially_pausable/_PartiallyPausable.sol
+++ b/contracts/security/partially_pausable/_PartiallyPausable.sol
@@ -3,13 +3,13 @@
 pragma solidity ^0.8.20;
 
 import { PausableStorage } from '../../storage/PausableStorage.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _IPartiallyPausable } from './_IPartiallyPausable.sol';
 
 /**
  * @title Internal functions for PartiallyPausable security control module.
  */
-abstract contract _PartiallyPausable is _IPartiallyPausable, MsgSenderTrick {
+abstract contract _PartiallyPausable is _IPartiallyPausable, _MsgSenderTrick {
     modifier whenNotPartiallyPaused(bytes32 key) {
         if (_partiallyPaused(key)) revert PartiallyPausable__PartiallyPaused();
         _;
diff --git a/contracts/security/pausable/_IPausable.sol b/contracts/security/pausable/_IPausable.sol
index 5822ef59d..eea73037c 100644
--- a/contracts/security/pausable/_IPausable.sol
+++ b/contracts/security/pausable/_IPausable.sol
@@ -2,7 +2,9 @@
 
 pragma solidity ^0.8.20;
 
-interface _IPausable {
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+
+interface _IPausable is _IMsgSenderTrick {
     error Pausable__Paused();
     error Pausable__NotPaused();
 
diff --git a/contracts/security/pausable/_Pausable.sol b/contracts/security/pausable/_Pausable.sol
index 07cf5972d..50e4ad0a3 100644
--- a/contracts/security/pausable/_Pausable.sol
+++ b/contracts/security/pausable/_Pausable.sol
@@ -3,13 +3,13 @@
 pragma solidity ^0.8.20;
 
 import { PausableStorage } from '../../storage/PausableStorage.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _IPausable } from './_IPausable.sol';
 
 /**
  * @title Internal functions for Pausable security control module.
  */
-abstract contract _Pausable is _IPausable, MsgSenderTrick {
+abstract contract _Pausable is _IPausable, _MsgSenderTrick {
     modifier whenNotPaused() {
         if (_paused()) revert Pausable__Paused();
         _;
diff --git a/contracts/token/fungible/_FungibleToken.sol b/contracts/token/fungible/_FungibleToken.sol
index ebbf43553..9cfab028f 100644
--- a/contracts/token/fungible/_FungibleToken.sol
+++ b/contracts/token/fungible/_FungibleToken.sol
@@ -3,13 +3,13 @@
 pragma solidity ^0.8.20;
 
 import { ERC20Storage } from '../../storage/ERC20Storage.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _IFungibleToken } from './_IFungibleToken.sol';
 
 /**
  * @title Base FungibleToken internal functions, excluding optional extensions
  */
-abstract contract _FungibleToken is _IFungibleToken, MsgSenderTrick {
+abstract contract _FungibleToken is _IFungibleToken, _MsgSenderTrick {
     /**
      * @notice query the total minted token supply
      * @return token supply
diff --git a/contracts/token/fungible/_IFungibleToken.sol b/contracts/token/fungible/_IFungibleToken.sol
index 33397ad3a..5e545bb7a 100644
--- a/contracts/token/fungible/_IFungibleToken.sol
+++ b/contracts/token/fungible/_IFungibleToken.sol
@@ -3,11 +3,12 @@
 pragma solidity ^0.8.20;
 
 import { _IERC20 } from '../../interfaces/_IERC20.sol';
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
 
 /**
  * @title FungibleToken base interface
  */
-interface _IFungibleToken is _IERC20 {
+interface _IFungibleToken is _IERC20, _IMsgSenderTrick {
     error FungibleToken__ApproveFromZeroAddress();
     error FungibleToken__ApproveToZeroAddress();
     error FungibleToken__BurnExceedsBalance();
diff --git a/contracts/token/multi/_IMultiToken.sol b/contracts/token/multi/_IMultiToken.sol
index 61ad7dc2d..e087df520 100644
--- a/contracts/token/multi/_IMultiToken.sol
+++ b/contracts/token/multi/_IMultiToken.sol
@@ -4,11 +4,12 @@ pragma solidity ^0.8.20;
 
 import { _IERC1155 } from '../../interfaces/_IERC1155.sol';
 import { _IIntrospectable } from '../../introspection/_IIntrospectable.sol';
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
 
 /**
  * @title MultiToken base interface
  */
-interface _IMultiToken is _IERC1155, _IIntrospectable {
+interface _IMultiToken is _IERC1155, _IIntrospectable, _IMsgSenderTrick {
     error MultiToken__ArrayLengthMismatch();
     error MultiToken__BalanceQueryZeroAddress();
     error MultiToken__NotOwnerOrApproved();
diff --git a/contracts/token/multi/_MultiToken.sol b/contracts/token/multi/_MultiToken.sol
index e2f9c927c..388de360a 100644
--- a/contracts/token/multi/_MultiToken.sol
+++ b/contracts/token/multi/_MultiToken.sol
@@ -6,14 +6,18 @@ import { IERC1155Receiver } from '../../interfaces/IERC1155Receiver.sol';
 import { _Introspectable } from '../../introspection/_Introspectable.sol';
 import { ERC1155Storage } from '../../storage/ERC1155Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _IMultiToken } from './_IMultiToken.sol';
 
 /**
  * @title Base MultiToken internal functions
  * @dev derived from https://github.com/OpenZeppelin/openzeppelin-contracts/ (MIT license)
  */
-abstract contract _MultiToken is _IMultiToken, _Introspectable, MsgSenderTrick {
+abstract contract _MultiToken is
+    _IMultiToken,
+    _Introspectable,
+    _MsgSenderTrick
+{
     using AddressUtils for address;
 
     /**
diff --git a/contracts/token/non_fungible/_INonFungibleToken.sol b/contracts/token/non_fungible/_INonFungibleToken.sol
index d07d783f7..dc1b42ec7 100644
--- a/contracts/token/non_fungible/_INonFungibleToken.sol
+++ b/contracts/token/non_fungible/_INonFungibleToken.sol
@@ -4,11 +4,12 @@ pragma solidity ^0.8.20;
 
 import { _IERC721 } from '../../interfaces/_IERC721.sol';
 import { _IIntrospectable } from '../../introspection/_IIntrospectable.sol';
+import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
 
 /**
  * @title NonFungibleToken base interface
  */
-interface _INonFungibleToken is _IERC721, _IIntrospectable {
+interface _INonFungibleToken is _IERC721, _IIntrospectable, _IMsgSenderTrick {
     error NonFungibleToken__NotOwnerOrApproved();
     error NonFungibleToken__SelfApproval();
     error NonFungibleToken__BalanceQueryZeroAddress();
diff --git a/contracts/token/non_fungible/_NonFungibleToken.sol b/contracts/token/non_fungible/_NonFungibleToken.sol
index 1bb461eea..f924494bf 100644
--- a/contracts/token/non_fungible/_NonFungibleToken.sol
+++ b/contracts/token/non_fungible/_NonFungibleToken.sol
@@ -8,7 +8,7 @@ import { IERC721Receiver } from '../../interfaces/IERC721Receiver.sol';
 import { _Introspectable } from '../../introspection/_Introspectable.sol';
 import { ERC721Storage } from '../../storage/ERC721Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { MsgSenderTrick } from '../../utils/MsgSenderTrick.sol';
+import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
 import { _INonFungibleToken } from './_INonFungibleToken.sol';
 
 /**
@@ -17,7 +17,7 @@ import { _INonFungibleToken } from './_INonFungibleToken.sol';
 abstract contract _NonFungibleToken is
     _INonFungibleToken,
     _Introspectable,
-    MsgSenderTrick
+    _MsgSenderTrick
 {
     using AddressUtils for address;
     using EnumerableMap for EnumerableMap.UintToAddressMap;
diff --git a/contracts/utils/_IMsgSenderTrick.sol b/contracts/utils/_IMsgSenderTrick.sol
new file mode 100644
index 000000000..f4f26e170
--- /dev/null
+++ b/contracts/utils/_IMsgSenderTrick.sol
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+interface _IMsgSenderTrick {}
diff --git a/contracts/utils/MsgSenderTrick.sol b/contracts/utils/_MsgSenderTrick.sol
similarity index 95%
rename from contracts/utils/MsgSenderTrick.sol
rename to contracts/utils/_MsgSenderTrick.sol
index 19fec0aa2..e4d362d9d 100644
--- a/contracts/utils/MsgSenderTrick.sol
+++ b/contracts/utils/_MsgSenderTrick.sol
@@ -2,10 +2,11 @@
 
 pragma solidity ^0.8.20;
 
+import { _IMsgSenderTrick } from './_IMsgSenderTrick.sol';
 /**
  * @title Utility contract for supporting alternative authorization schemes
  */
-abstract contract MsgSenderTrick {
+abstract contract _MsgSenderTrick is _IMsgSenderTrick {
     /*
      * @notice Returns the intended sender of a message. Either msg.sender or the address of the authorizing signer.
      *         Enables MetaTransactions, since the sender doesn't need to be the tx.origin or even the msg.sender.

From 9a0af0ad47fd5d4a4a63641a6e435da42d11aee7 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:09:51 -0600
Subject: [PATCH 06/33] rename MsgSenderTrick to Context

---
 contracts/access/access_control/_AccessControl.sol        | 4 ++--
 contracts/access/access_control/_IAccessControl.sol       | 4 ++--
 contracts/access/ownable/_IOwnable.sol                    | 4 ++--
 contracts/access/ownable/_Ownable.sol                     | 4 ++--
 .../security/partially_pausable/_IPartiallyPausable.sol   | 4 ++--
 .../security/partially_pausable/_PartiallyPausable.sol    | 4 ++--
 contracts/security/pausable/_IPausable.sol                | 4 ++--
 contracts/security/pausable/_Pausable.sol                 | 4 ++--
 contracts/token/fungible/_FungibleToken.sol               | 4 ++--
 contracts/token/fungible/_IFungibleToken.sol              | 4 ++--
 contracts/token/multi/_IMultiToken.sol                    | 4 ++--
 contracts/token/multi/_MultiToken.sol                     | 8 ++------
 contracts/token/non_fungible/_INonFungibleToken.sol       | 4 ++--
 contracts/token/non_fungible/_NonFungibleToken.sol        | 4 ++--
 contracts/utils/{_MsgSenderTrick.sol => _Context.sol}     | 4 ++--
 contracts/utils/{_IMsgSenderTrick.sol => _IContext.sol}   | 2 +-
 16 files changed, 31 insertions(+), 35 deletions(-)
 rename contracts/utils/{_MsgSenderTrick.sol => _Context.sol} (95%)
 rename contracts/utils/{_IMsgSenderTrick.sol => _IContext.sol} (66%)

diff --git a/contracts/access/access_control/_AccessControl.sol b/contracts/access/access_control/_AccessControl.sol
index 98b3d2822..adad27111 100644
--- a/contracts/access/access_control/_AccessControl.sol
+++ b/contracts/access/access_control/_AccessControl.sol
@@ -6,14 +6,14 @@ import { EnumerableSet } from '../../data/EnumerableSet.sol';
 import { AccessControlStorage } from '../../storage/AccessControlStorage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
 import { UintUtils } from '../../utils/UintUtils.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _IAccessControl } from './_IAccessControl.sol';
 
 /**
  * @title Role-based access control system
  * @dev derived from https://github.com/OpenZeppelin/openzeppelin-contracts (MIT license)
  */
-abstract contract _AccessControl is _IAccessControl, _MsgSenderTrick {
+abstract contract _AccessControl is _IAccessControl, _Context {
     using AddressUtils for address;
     using EnumerableSet for EnumerableSet.AddressSet;
     using UintUtils for uint256;
diff --git a/contracts/access/access_control/_IAccessControl.sol b/contracts/access/access_control/_IAccessControl.sol
index 53216fdf6..0c089851c 100644
--- a/contracts/access/access_control/_IAccessControl.sol
+++ b/contracts/access/access_control/_IAccessControl.sol
@@ -2,12 +2,12 @@
 
 pragma solidity ^0.8.20;
 
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
 /**
  * @title Partial AccessControl interface needed by internal functions
  */
-interface _IAccessControl is _IMsgSenderTrick {
+interface _IAccessControl is _IContext {
     event RoleAdminChanged(
         bytes32 indexed role,
         bytes32 indexed previousAdminRole,
diff --git a/contracts/access/ownable/_IOwnable.sol b/contracts/access/ownable/_IOwnable.sol
index ddf13984e..b3ec83597 100644
--- a/contracts/access/ownable/_IOwnable.sol
+++ b/contracts/access/ownable/_IOwnable.sol
@@ -3,9 +3,9 @@
 pragma solidity ^0.8.20;
 
 import { _IERC173 } from '../../interfaces/_IERC173.sol';
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
-interface _IOwnable is _IERC173, _IMsgSenderTrick {
+interface _IOwnable is _IERC173, _IContext {
     error Ownable__NotOwner();
     error Ownable__NotTransitiveOwner();
 }
diff --git a/contracts/access/ownable/_Ownable.sol b/contracts/access/ownable/_Ownable.sol
index 178fb772f..d53c21a90 100644
--- a/contracts/access/ownable/_Ownable.sol
+++ b/contracts/access/ownable/_Ownable.sol
@@ -5,10 +5,10 @@ pragma solidity ^0.8.20;
 import { IERC173 } from '../../interfaces/IERC173.sol';
 import { ERC173Storage } from '../../storage/ERC173Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _IOwnable } from './_IOwnable.sol';
 
-abstract contract _Ownable is _IOwnable, _MsgSenderTrick {
+abstract contract _Ownable is _IOwnable, _Context {
     using AddressUtils for address;
 
     modifier onlyOwner() {
diff --git a/contracts/security/partially_pausable/_IPartiallyPausable.sol b/contracts/security/partially_pausable/_IPartiallyPausable.sol
index c6eedb2f9..1705072c5 100644
--- a/contracts/security/partially_pausable/_IPartiallyPausable.sol
+++ b/contracts/security/partially_pausable/_IPartiallyPausable.sol
@@ -2,9 +2,9 @@
 
 pragma solidity ^0.8.20;
 
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
-interface _IPartiallyPausable is _IMsgSenderTrick {
+interface _IPartiallyPausable is _IContext {
     error PartiallyPausable__PartiallyPaused();
     error PartiallyPausable__NotPartiallyPaused();
 
diff --git a/contracts/security/partially_pausable/_PartiallyPausable.sol b/contracts/security/partially_pausable/_PartiallyPausable.sol
index d610f497b..f510d1334 100644
--- a/contracts/security/partially_pausable/_PartiallyPausable.sol
+++ b/contracts/security/partially_pausable/_PartiallyPausable.sol
@@ -3,13 +3,13 @@
 pragma solidity ^0.8.20;
 
 import { PausableStorage } from '../../storage/PausableStorage.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _IPartiallyPausable } from './_IPartiallyPausable.sol';
 
 /**
  * @title Internal functions for PartiallyPausable security control module.
  */
-abstract contract _PartiallyPausable is _IPartiallyPausable, _MsgSenderTrick {
+abstract contract _PartiallyPausable is _IPartiallyPausable, _Context {
     modifier whenNotPartiallyPaused(bytes32 key) {
         if (_partiallyPaused(key)) revert PartiallyPausable__PartiallyPaused();
         _;
diff --git a/contracts/security/pausable/_IPausable.sol b/contracts/security/pausable/_IPausable.sol
index eea73037c..1c2dca946 100644
--- a/contracts/security/pausable/_IPausable.sol
+++ b/contracts/security/pausable/_IPausable.sol
@@ -2,9 +2,9 @@
 
 pragma solidity ^0.8.20;
 
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
-interface _IPausable is _IMsgSenderTrick {
+interface _IPausable is _IContext {
     error Pausable__Paused();
     error Pausable__NotPaused();
 
diff --git a/contracts/security/pausable/_Pausable.sol b/contracts/security/pausable/_Pausable.sol
index 50e4ad0a3..2e6bf39da 100644
--- a/contracts/security/pausable/_Pausable.sol
+++ b/contracts/security/pausable/_Pausable.sol
@@ -3,13 +3,13 @@
 pragma solidity ^0.8.20;
 
 import { PausableStorage } from '../../storage/PausableStorage.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _IPausable } from './_IPausable.sol';
 
 /**
  * @title Internal functions for Pausable security control module.
  */
-abstract contract _Pausable is _IPausable, _MsgSenderTrick {
+abstract contract _Pausable is _IPausable, _Context {
     modifier whenNotPaused() {
         if (_paused()) revert Pausable__Paused();
         _;
diff --git a/contracts/token/fungible/_FungibleToken.sol b/contracts/token/fungible/_FungibleToken.sol
index 9cfab028f..440b5ae81 100644
--- a/contracts/token/fungible/_FungibleToken.sol
+++ b/contracts/token/fungible/_FungibleToken.sol
@@ -3,13 +3,13 @@
 pragma solidity ^0.8.20;
 
 import { ERC20Storage } from '../../storage/ERC20Storage.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _IFungibleToken } from './_IFungibleToken.sol';
 
 /**
  * @title Base FungibleToken internal functions, excluding optional extensions
  */
-abstract contract _FungibleToken is _IFungibleToken, _MsgSenderTrick {
+abstract contract _FungibleToken is _IFungibleToken, _Context {
     /**
      * @notice query the total minted token supply
      * @return token supply
diff --git a/contracts/token/fungible/_IFungibleToken.sol b/contracts/token/fungible/_IFungibleToken.sol
index 5e545bb7a..0757ff671 100644
--- a/contracts/token/fungible/_IFungibleToken.sol
+++ b/contracts/token/fungible/_IFungibleToken.sol
@@ -3,12 +3,12 @@
 pragma solidity ^0.8.20;
 
 import { _IERC20 } from '../../interfaces/_IERC20.sol';
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
 /**
  * @title FungibleToken base interface
  */
-interface _IFungibleToken is _IERC20, _IMsgSenderTrick {
+interface _IFungibleToken is _IERC20, _IContext {
     error FungibleToken__ApproveFromZeroAddress();
     error FungibleToken__ApproveToZeroAddress();
     error FungibleToken__BurnExceedsBalance();
diff --git a/contracts/token/multi/_IMultiToken.sol b/contracts/token/multi/_IMultiToken.sol
index e087df520..214bc256e 100644
--- a/contracts/token/multi/_IMultiToken.sol
+++ b/contracts/token/multi/_IMultiToken.sol
@@ -4,12 +4,12 @@ pragma solidity ^0.8.20;
 
 import { _IERC1155 } from '../../interfaces/_IERC1155.sol';
 import { _IIntrospectable } from '../../introspection/_IIntrospectable.sol';
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
 /**
  * @title MultiToken base interface
  */
-interface _IMultiToken is _IERC1155, _IIntrospectable, _IMsgSenderTrick {
+interface _IMultiToken is _IERC1155, _IIntrospectable, _IContext {
     error MultiToken__ArrayLengthMismatch();
     error MultiToken__BalanceQueryZeroAddress();
     error MultiToken__NotOwnerOrApproved();
diff --git a/contracts/token/multi/_MultiToken.sol b/contracts/token/multi/_MultiToken.sol
index 388de360a..cbffd0b3f 100644
--- a/contracts/token/multi/_MultiToken.sol
+++ b/contracts/token/multi/_MultiToken.sol
@@ -6,18 +6,14 @@ import { IERC1155Receiver } from '../../interfaces/IERC1155Receiver.sol';
 import { _Introspectable } from '../../introspection/_Introspectable.sol';
 import { ERC1155Storage } from '../../storage/ERC1155Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _IMultiToken } from './_IMultiToken.sol';
 
 /**
  * @title Base MultiToken internal functions
  * @dev derived from https://github.com/OpenZeppelin/openzeppelin-contracts/ (MIT license)
  */
-abstract contract _MultiToken is
-    _IMultiToken,
-    _Introspectable,
-    _MsgSenderTrick
-{
+abstract contract _MultiToken is _IMultiToken, _Introspectable, _Context {
     using AddressUtils for address;
 
     /**
diff --git a/contracts/token/non_fungible/_INonFungibleToken.sol b/contracts/token/non_fungible/_INonFungibleToken.sol
index dc1b42ec7..bc4de714a 100644
--- a/contracts/token/non_fungible/_INonFungibleToken.sol
+++ b/contracts/token/non_fungible/_INonFungibleToken.sol
@@ -4,12 +4,12 @@ pragma solidity ^0.8.20;
 
 import { _IERC721 } from '../../interfaces/_IERC721.sol';
 import { _IIntrospectable } from '../../introspection/_IIntrospectable.sol';
-import { _IMsgSenderTrick } from '../../utils/_IMsgSenderTrick.sol';
+import { _IContext } from '../../utils/_IContext.sol';
 
 /**
  * @title NonFungibleToken base interface
  */
-interface _INonFungibleToken is _IERC721, _IIntrospectable, _IMsgSenderTrick {
+interface _INonFungibleToken is _IERC721, _IIntrospectable, _IContext {
     error NonFungibleToken__NotOwnerOrApproved();
     error NonFungibleToken__SelfApproval();
     error NonFungibleToken__BalanceQueryZeroAddress();
diff --git a/contracts/token/non_fungible/_NonFungibleToken.sol b/contracts/token/non_fungible/_NonFungibleToken.sol
index 49d4c8429..899d84240 100644
--- a/contracts/token/non_fungible/_NonFungibleToken.sol
+++ b/contracts/token/non_fungible/_NonFungibleToken.sol
@@ -8,7 +8,7 @@ import { IERC721Receiver } from '../../interfaces/IERC721Receiver.sol';
 import { _Introspectable } from '../../introspection/_Introspectable.sol';
 import { ERC721Storage } from '../../storage/ERC721Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { _MsgSenderTrick } from '../../utils/_MsgSenderTrick.sol';
+import { _Context } from '../../utils/_Context.sol';
 import { _INonFungibleToken } from './_INonFungibleToken.sol';
 
 /**
@@ -17,7 +17,7 @@ import { _INonFungibleToken } from './_INonFungibleToken.sol';
 abstract contract _NonFungibleToken is
     _INonFungibleToken,
     _Introspectable,
-    _MsgSenderTrick
+    _Context
 {
     using AddressUtils for address;
     using EnumerableMap for EnumerableMap.UintToAddressMap;
diff --git a/contracts/utils/_MsgSenderTrick.sol b/contracts/utils/_Context.sol
similarity index 95%
rename from contracts/utils/_MsgSenderTrick.sol
rename to contracts/utils/_Context.sol
index e4d362d9d..2a0107fc2 100644
--- a/contracts/utils/_MsgSenderTrick.sol
+++ b/contracts/utils/_Context.sol
@@ -2,11 +2,11 @@
 
 pragma solidity ^0.8.20;
 
-import { _IMsgSenderTrick } from './_IMsgSenderTrick.sol';
+import { _IContext } from './_IContext.sol';
 /**
  * @title Utility contract for supporting alternative authorization schemes
  */
-abstract contract _MsgSenderTrick is _IMsgSenderTrick {
+abstract contract _Context is _IContext {
     /*
      * @notice Returns the intended sender of a message. Either msg.sender or the address of the authorizing signer.
      *         Enables MetaTransactions, since the sender doesn't need to be the tx.origin or even the msg.sender.
diff --git a/contracts/utils/_IMsgSenderTrick.sol b/contracts/utils/_IContext.sol
similarity index 66%
rename from contracts/utils/_IMsgSenderTrick.sol
rename to contracts/utils/_IContext.sol
index f4f26e170..c1a257897 100644
--- a/contracts/utils/_IMsgSenderTrick.sol
+++ b/contracts/utils/_IContext.sol
@@ -2,4 +2,4 @@
 
 pragma solidity ^0.8.20;
 
-interface _IMsgSenderTrick {}
+interface _IContext {}

From 6c93a45050cd3c73c3d65e84e71bc494dc8fc498 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:29:42 -0600
Subject: [PATCH 07/33] expand _Context to _MetaTransactionContext

---
 contracts/utils/_Context.sol                 | 46 +---------------
 contracts/utils/_IMetaTransactionContext.sol |  7 +++
 contracts/utils/_MetaTransactionContext.sol  | 58 ++++++++++++++++++++
 3 files changed, 67 insertions(+), 44 deletions(-)
 create mode 100644 contracts/utils/_IMetaTransactionContext.sol
 create mode 100644 contracts/utils/_MetaTransactionContext.sol

diff --git a/contracts/utils/_Context.sol b/contracts/utils/_Context.sol
index 2a0107fc2..dd8272844 100644
--- a/contracts/utils/_Context.sol
+++ b/contracts/utils/_Context.sol
@@ -7,49 +7,7 @@ import { _IContext } from './_IContext.sol';
  * @title Utility contract for supporting alternative authorization schemes
  */
 abstract contract _Context is _IContext {
-    /*
-     * @notice Returns the intended sender of a message. Either msg.sender or the address of the authorizing signer.
-     *         Enables MetaTransactions, since the sender doesn't need to be the tx.origin or even the msg.sender.
-     * @returns address - The account whose authority is being acted on.
-     * and the end-user for GSN relayed calls (where msg.sender is actually `RelayHub`).
-     *
-     * IMPORTANT: Contracts derived from {GSNRecipient} should never use `msg.sender`, and use {_msgSender} instead.
-     */
-    function _msgSender() internal view virtual returns (address sender) {
-        if (msg.sender == address(this)) {
-            return _getRelayedCallSender();
-        } else {
-            sender = msg.sender;
-        }
-        return sender;
-    }
-
-    function _getRelayedCallSender()
-        private
-        pure
-        returns (address payable result)
-    {
-        // We need to read 20 bytes (an address) located at array index msg.data.length - 20. In memory, the array
-        // is prefixed with a 32-byte length value, so we first add 32 to get the memory read index. However, doing
-        // so would leave the address in the upper 20 bytes of the 32-byte word, which is inconvenient and would
-        // require bit shifting. We therefore subtract 12 from the read index so the address lands on the lower 20
-        // bytes. This can always be done due to the 32-byte prefix.
-
-        // The final memory read index is msg.data.length - 20 + 32 - 12 = msg.data.length. Using inline assembly is the
-        // easiest/most-efficient way to perform this operation.
-
-        // These fields are not accessible from assembly
-        bytes memory array = msg.data;
-        uint256 index = msg.data.length;
-
-        // solhint-disable-next-line no-inline-assembly
-        assembly {
-            // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
-            result := and(
-                mload(add(array, index)),
-                0xffffffffffffffffffffffffffffffffffffffff
-            )
-        }
-        return result;
+    function _msgSender() internal view virtual returns (address msgSender) {
+        msgSender = msg.sender;
     }
 }
diff --git a/contracts/utils/_IMetaTransactionContext.sol b/contracts/utils/_IMetaTransactionContext.sol
new file mode 100644
index 000000000..3c4a8af2a
--- /dev/null
+++ b/contracts/utils/_IMetaTransactionContext.sol
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { _IContext } from './_IContext.sol';
+
+interface _IMetaTransactionContext is _IContext {}
diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
new file mode 100644
index 000000000..7fd07c295
--- /dev/null
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { _Context } from './_Context.sol';
+
+abstract contract _MetaTransactionContext is _Context {
+    /*
+     * @notice Returns the intended sender of a message. Either msg.sender or the address of the authorizing signer.
+     *         Enables MetaTransactions, since the sender doesn't need to be the tx.origin or even the msg.sender.
+     * @returns address - The account whose authority is being acted on.
+     * and the end-user for GSN relayed calls (where msg.sender is actually `RelayHub`).
+     *
+     * IMPORTANT: Contracts derived from {GSNRecipient} should never use `msg.sender`, and use {_msgSender} instead.
+     */
+    function _msgSender()
+        internal
+        view
+        virtual
+        override
+        returns (address msgSender)
+    {
+        if (msg.sender == address(this)) {
+            msgSender = _getRelayedCallSender();
+        } else {
+            msgSender = msg.sender;
+        }
+    }
+
+    function _getRelayedCallSender()
+        private
+        pure
+        returns (address payable result)
+    {
+        // We need to read 20 bytes (an address) located at array index msg.data.length - 20. In memory, the array
+        // is prefixed with a 32-byte length value, so we first add 32 to get the memory read index. However, doing
+        // so would leave the address in the upper 20 bytes of the 32-byte word, which is inconvenient and would
+        // require bit shifting. We therefore subtract 12 from the read index so the address lands on the lower 20
+        // bytes. This can always be done due to the 32-byte prefix.
+
+        // The final memory read index is msg.data.length - 20 + 32 - 12 = msg.data.length. Using inline assembly is the
+        // easiest/most-efficient way to perform this operation.
+
+        // These fields are not accessible from assembly
+        bytes memory array = msg.data;
+        uint256 index = msg.data.length;
+
+        // solhint-disable-next-line no-inline-assembly
+        assembly {
+            // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
+            result := and(
+                mload(add(array, index)),
+                0xffffffffffffffffffffffffffffffffffffffff
+            )
+        }
+        return result;
+    }
+}

From caf52fc1c5ac4122323be88ca5405453bee6ef79 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:32:25 -0600
Subject: [PATCH 08/33] add ERC2771 interfaces and storage library

---
 contracts/interfaces/IERC2771.sol    |  9 ++++++++
 contracts/interfaces/_IERC2771.sol   |  5 +++++
 contracts/storage/ERC2771Storage.sol | 31 ++++++++++++++++++++++++++++
 3 files changed, 45 insertions(+)
 create mode 100644 contracts/interfaces/IERC2771.sol
 create mode 100644 contracts/interfaces/_IERC2771.sol
 create mode 100644 contracts/storage/ERC2771Storage.sol

diff --git a/contracts/interfaces/IERC2771.sol b/contracts/interfaces/IERC2771.sol
new file mode 100644
index 000000000..5a6a1826f
--- /dev/null
+++ b/contracts/interfaces/IERC2771.sol
@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { _IERC2771 } from './_IERC2771.sol';
+
+interface IERC2771 is _IERC2771 {
+    function isTrustedForwarder(address forwarder) external view returns (bool);
+}
diff --git a/contracts/interfaces/_IERC2771.sol b/contracts/interfaces/_IERC2771.sol
new file mode 100644
index 000000000..eecfcb360
--- /dev/null
+++ b/contracts/interfaces/_IERC2771.sol
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+interface _IERC2771 {}
diff --git a/contracts/storage/ERC2771Storage.sol b/contracts/storage/ERC2771Storage.sol
new file mode 100644
index 000000000..6b86c25de
--- /dev/null
+++ b/contracts/storage/ERC2771Storage.sol
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+library ERC2771Storage {
+    /**
+     * @custom:storage-location erc7201:solidstate.contracts.storage.ERC2771
+     */
+    struct Layout {
+        mapping(address account => bool trustedStatus) trustedForwarders;
+    }
+
+    bytes32 internal constant DEFAULT_STORAGE_SLOT =
+        keccak256(
+            abi.encode(
+                uint256(
+                    keccak256(bytes('solidstate.contracts.storage.ERC2771'))
+                ) - 1
+            )
+        ) & ~bytes32(uint256(0xff));
+
+    function layout() internal pure returns (Layout storage $) {
+        $ = layout(DEFAULT_STORAGE_SLOT);
+    }
+
+    function layout(bytes32 slot) internal pure returns (Layout storage $) {
+        assembly {
+            $.slot := slot
+        }
+    }
+}

From 93d35e2a21bfbc63b866f9b2642f922b35df5798 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:40:57 -0600
Subject: [PATCH 09/33] remove _getRelayedCallSender helper

---
 contracts/utils/_MetaTransactionContext.sol | 49 +++++++++------------
 1 file changed, 20 insertions(+), 29 deletions(-)

diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
index 7fd07c295..0cf9f8f9b 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -21,38 +21,29 @@ abstract contract _MetaTransactionContext is _Context {
         returns (address msgSender)
     {
         if (msg.sender == address(this)) {
-            msgSender = _getRelayedCallSender();
-        } else {
-            msgSender = msg.sender;
-        }
-    }
+            // We need to read 20 bytes (an address) located at array index msg.data.length - 20. In memory, the array
+            // is prefixed with a 32-byte length value, so we first add 32 to get the memory read index. However, doing
+            // so would leave the address in the upper 20 bytes of the 32-byte word, which is inconvenient and would
+            // require bit shifting. We therefore subtract 12 from the read index so the address lands on the lower 20
+            // bytes. This can always be done due to the 32-byte prefix.
 
-    function _getRelayedCallSender()
-        private
-        pure
-        returns (address payable result)
-    {
-        // We need to read 20 bytes (an address) located at array index msg.data.length - 20. In memory, the array
-        // is prefixed with a 32-byte length value, so we first add 32 to get the memory read index. However, doing
-        // so would leave the address in the upper 20 bytes of the 32-byte word, which is inconvenient and would
-        // require bit shifting. We therefore subtract 12 from the read index so the address lands on the lower 20
-        // bytes. This can always be done due to the 32-byte prefix.
-
-        // The final memory read index is msg.data.length - 20 + 32 - 12 = msg.data.length. Using inline assembly is the
-        // easiest/most-efficient way to perform this operation.
+            // The final memory read index is msg.data.length - 20 + 32 - 12 = msg.data.length. Using inline assembly is the
+            // easiest/most-efficient way to perform this operation.
 
-        // These fields are not accessible from assembly
-        bytes memory array = msg.data;
-        uint256 index = msg.data.length;
+            // These fields are not accessible from assembly
+            bytes memory array = msg.data;
+            uint256 index = msg.data.length;
 
-        // solhint-disable-next-line no-inline-assembly
-        assembly {
-            // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
-            result := and(
-                mload(add(array, index)),
-                0xffffffffffffffffffffffffffffffffffffffff
-            )
+            // solhint-disable-next-line no-inline-assembly
+            assembly {
+                // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
+                msgSender := and(
+                    mload(add(array, index)),
+                    0xffffffffffffffffffffffffffffffffffffffff
+                )
+            }
+        } else {
+            msgSender = msg.sender;
         }
-        return result;
     }
 }

From 645bcb4b25792258a00440009148b65ccbc80721 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:54:18 -0600
Subject: [PATCH 10/33] add msg.data processing functions to Context

---
 contracts/utils/_Context.sol                | 13 +++++++++++
 contracts/utils/_MetaTransactionContext.sol | 24 +++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/contracts/utils/_Context.sol b/contracts/utils/_Context.sol
index dd8272844..739d5c987 100644
--- a/contracts/utils/_Context.sol
+++ b/contracts/utils/_Context.sol
@@ -10,4 +10,17 @@ abstract contract _Context is _IContext {
     function _msgSender() internal view virtual returns (address msgSender) {
         msgSender = msg.sender;
     }
+
+    function _msgData() internal view virtual returns (bytes calldata msgData) {
+        msgData = msg.data;
+    }
+
+    function _calldataSuffixLength()
+        internal
+        view
+        virtual
+        returns (uint256 length)
+    {
+        length = 0;
+    }
 }
diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
index 0cf9f8f9b..e59cc8b79 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -46,4 +46,28 @@ abstract contract _MetaTransactionContext is _Context {
             msgSender = msg.sender;
         }
     }
+
+    function _msgData()
+        internal
+        view
+        virtual
+        override
+        returns (bytes calldata msgData)
+    {
+        if (msg.sender == address(this)) {
+            msgData = msg.data[:msg.data.length - _calldataSuffixLength()];
+        } else {
+            msgData = msg.data;
+        }
+    }
+
+    function _calldataSuffixLength()
+        internal
+        view
+        virtual
+        override
+        returns (uint256 length)
+    {
+        length = 20;
+    }
 }

From df41fde45a1cd03c72144a079e5d17f54060e7b1 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:56:04 -0600
Subject: [PATCH 11/33] use super calls to Context

---
 contracts/utils/_MetaTransactionContext.sol | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
index e59cc8b79..911ebaf4b 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -43,7 +43,7 @@ abstract contract _MetaTransactionContext is _Context {
                 )
             }
         } else {
-            msgSender = msg.sender;
+            msgSender = super._msgSender();
         }
     }
 
@@ -57,7 +57,7 @@ abstract contract _MetaTransactionContext is _Context {
         if (msg.sender == address(this)) {
             msgData = msg.data[:msg.data.length - _calldataSuffixLength()];
         } else {
-            msgData = msg.data;
+            msgData = super._msgData();
         }
     }
 

From 530275805bce42b4e4f408b36d50f084fc3d3bb5 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:56:56 -0600
Subject: [PATCH 12/33] remove Context comments

---
 contracts/utils/_MetaTransactionContext.sol | 20 --------------------
 1 file changed, 20 deletions(-)

diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
index 911ebaf4b..b91e87e79 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -5,14 +5,6 @@ pragma solidity ^0.8.20;
 import { _Context } from './_Context.sol';
 
 abstract contract _MetaTransactionContext is _Context {
-    /*
-     * @notice Returns the intended sender of a message. Either msg.sender or the address of the authorizing signer.
-     *         Enables MetaTransactions, since the sender doesn't need to be the tx.origin or even the msg.sender.
-     * @returns address - The account whose authority is being acted on.
-     * and the end-user for GSN relayed calls (where msg.sender is actually `RelayHub`).
-     *
-     * IMPORTANT: Contracts derived from {GSNRecipient} should never use `msg.sender`, and use {_msgSender} instead.
-     */
     function _msgSender()
         internal
         view
@@ -21,22 +13,10 @@ abstract contract _MetaTransactionContext is _Context {
         returns (address msgSender)
     {
         if (msg.sender == address(this)) {
-            // We need to read 20 bytes (an address) located at array index msg.data.length - 20. In memory, the array
-            // is prefixed with a 32-byte length value, so we first add 32 to get the memory read index. However, doing
-            // so would leave the address in the upper 20 bytes of the 32-byte word, which is inconvenient and would
-            // require bit shifting. We therefore subtract 12 from the read index so the address lands on the lower 20
-            // bytes. This can always be done due to the 32-byte prefix.
-
-            // The final memory read index is msg.data.length - 20 + 32 - 12 = msg.data.length. Using inline assembly is the
-            // easiest/most-efficient way to perform this operation.
-
-            // These fields are not accessible from assembly
             bytes memory array = msg.data;
             uint256 index = msg.data.length;
 
-            // solhint-disable-next-line no-inline-assembly
             assembly {
-                // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
                 msgSender := and(
                     mload(add(array, index)),
                     0xffffffffffffffffffffffffffffffffffffffff

From 4fd84f17023589964ed9f005b74d0c8825f0fe16 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 13:59:16 -0600
Subject: [PATCH 13/33] remove assembly in _msgSender

---
 contracts/utils/_MetaTransactionContext.sol | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
index b91e87e79..a90ed06d9 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -13,15 +13,9 @@ abstract contract _MetaTransactionContext is _Context {
         returns (address msgSender)
     {
         if (msg.sender == address(this)) {
-            bytes memory array = msg.data;
-            uint256 index = msg.data.length;
-
-            assembly {
-                msgSender := and(
-                    mload(add(array, index)),
-                    0xffffffffffffffffffffffffffffffffffffffff
-                )
-            }
+            msgSender = address(
+                bytes20(msg.data[msg.data.length - _calldataSuffixLength():])
+            );
         } else {
             msgSender = super._msgSender();
         }

From 78c875d10e3069997ec841424aad62f92423331c Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 14:08:42 -0600
Subject: [PATCH 14/33] add Context comments

---
 contracts/utils/_Context.sol                | 16 ++++++++++++++++
 contracts/utils/_MetaTransactionContext.sol | 11 +++++++++++
 2 files changed, 27 insertions(+)

diff --git a/contracts/utils/_Context.sol b/contracts/utils/_Context.sol
index 739d5c987..303eab6c6 100644
--- a/contracts/utils/_Context.sol
+++ b/contracts/utils/_Context.sol
@@ -3,18 +3,34 @@
 pragma solidity ^0.8.20;
 
 import { _IContext } from './_IContext.sol';
+
 /**
  * @title Utility contract for supporting alternative authorization schemes
  */
 abstract contract _Context is _IContext {
+    /**
+     * @notice return the message sender
+     * @dev if no Context extension is in use, msg.sender is returned as-is
+     * @return msgSender account contextualized as message sender
+     */
     function _msgSender() internal view virtual returns (address msgSender) {
         msgSender = msg.sender;
     }
 
+    /**
+     * @notice return the message data
+     * @dev if no Context extension is in use, msg.data is returned as-is
+     * @return msgData message data with suffix removed, if applicable
+     */
     function _msgData() internal view virtual returns (bytes calldata msgData) {
         msgData = msg.data;
     }
 
+    /**
+     * @notice return the bytes length of the calldata context suffix
+     * @dev if no Context extension is in use, suffix length is 0
+     * @return length length of calldata context suffix
+     */
     function _calldataSuffixLength()
         internal
         view
diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_MetaTransactionContext.sol
index a90ed06d9..b1d99e326 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_MetaTransactionContext.sol
@@ -5,6 +5,10 @@ pragma solidity ^0.8.20;
 import { _Context } from './_Context.sol';
 
 abstract contract _MetaTransactionContext is _Context {
+    /**
+     * @inheritdoc _Context
+     * @dev sender is read from the calldata context suffix
+     */
     function _msgSender()
         internal
         view
@@ -21,6 +25,9 @@ abstract contract _MetaTransactionContext is _Context {
         }
     }
 
+    /**
+     * @inheritdoc _Context
+     */
     function _msgData()
         internal
         view
@@ -35,6 +42,10 @@ abstract contract _MetaTransactionContext is _Context {
         }
     }
 
+    /**
+     * @inheritdoc _Context
+     * @dev this Context extension defines an address suffix with a length of 20
+     */
     function _calldataSuffixLength()
         internal
         view

From 588aea2dfa8b4fc10f71a57d3dd728bfa44e2bb1 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 14:11:11 -0600
Subject: [PATCH 15/33] rename MetaTransactionContext to
 ForwardedMetaTransactionContext

---
 ...ansactionContext.sol => _ForwardedMetaTransationContext.sol} | 2 +-
 ...nsactionContext.sol => _IForwardedMetaTransationContext.sol} | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
 rename contracts/utils/{_MetaTransactionContext.sol => _ForwardedMetaTransationContext.sol} (95%)
 rename contracts/utils/{_IMetaTransactionContext.sol => _IForwardedMetaTransationContext.sol} (64%)

diff --git a/contracts/utils/_MetaTransactionContext.sol b/contracts/utils/_ForwardedMetaTransationContext.sol
similarity index 95%
rename from contracts/utils/_MetaTransactionContext.sol
rename to contracts/utils/_ForwardedMetaTransationContext.sol
index b1d99e326..e5f1b67c9 100644
--- a/contracts/utils/_MetaTransactionContext.sol
+++ b/contracts/utils/_ForwardedMetaTransationContext.sol
@@ -4,7 +4,7 @@ pragma solidity ^0.8.20;
 
 import { _Context } from './_Context.sol';
 
-abstract contract _MetaTransactionContext is _Context {
+abstract contract _ForwardedMetaTransationContext is _Context {
     /**
      * @inheritdoc _Context
      * @dev sender is read from the calldata context suffix
diff --git a/contracts/utils/_IMetaTransactionContext.sol b/contracts/utils/_IForwardedMetaTransationContext.sol
similarity index 64%
rename from contracts/utils/_IMetaTransactionContext.sol
rename to contracts/utils/_IForwardedMetaTransationContext.sol
index 3c4a8af2a..4b63e80d7 100644
--- a/contracts/utils/_IMetaTransactionContext.sol
+++ b/contracts/utils/_IForwardedMetaTransationContext.sol
@@ -4,4 +4,4 @@ pragma solidity ^0.8.20;
 
 import { _IContext } from './_IContext.sol';
 
-interface _IMetaTransactionContext is _IContext {}
+interface _IForwardedMetaTransationContext is _IContext {}

From e13a3e29d60d77577fd38e52d7e8f481129adfe7 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 14:20:49 -0600
Subject: [PATCH 16/33] conform ForwardedMetaTransactionContext to ERC2771

---
 .../utils/ForwardedMetaTransationContext.sol  | 17 ++++++++++++++++
 .../utils/IForwardedMetaTransationContext.sol | 11 ++++++++++
 .../utils/_ForwardedMetaTransationContext.sol | 20 ++++++++++++++++---
 .../_IForwardedMetaTransationContext.sol      |  3 ++-
 4 files changed, 47 insertions(+), 4 deletions(-)
 create mode 100644 contracts/utils/ForwardedMetaTransationContext.sol
 create mode 100644 contracts/utils/IForwardedMetaTransationContext.sol

diff --git a/contracts/utils/ForwardedMetaTransationContext.sol b/contracts/utils/ForwardedMetaTransationContext.sol
new file mode 100644
index 000000000..5a232a78b
--- /dev/null
+++ b/contracts/utils/ForwardedMetaTransationContext.sol
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { IForwardedMetaTransationContext } from './IForwardedMetaTransationContext.sol';
+import { _ForwardedMetaTransationContext } from './_ForwardedMetaTransationContext.sol';
+
+abstract contract ForwardedMetaTransationContext is
+    IForwardedMetaTransationContext,
+    _ForwardedMetaTransationContext
+{
+    function isTrustedForwarder(
+        address account
+    ) external view returns (bool trustedStatus) {
+        trustedStatus = _isTrustedForwarder(account);
+    }
+}
diff --git a/contracts/utils/IForwardedMetaTransationContext.sol b/contracts/utils/IForwardedMetaTransationContext.sol
new file mode 100644
index 000000000..ac7c108fa
--- /dev/null
+++ b/contracts/utils/IForwardedMetaTransationContext.sol
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { IERC2771 } from '../interfaces/IERC2771.sol';
+import { _IForwardedMetaTransationContext } from './_IForwardedMetaTransationContext.sol';
+
+interface IForwardedMetaTransationContext is
+    _IForwardedMetaTransationContext,
+    IERC2771
+{}
diff --git a/contracts/utils/_ForwardedMetaTransationContext.sol b/contracts/utils/_ForwardedMetaTransationContext.sol
index e5f1b67c9..aa0fba912 100644
--- a/contracts/utils/_ForwardedMetaTransationContext.sol
+++ b/contracts/utils/_ForwardedMetaTransationContext.sol
@@ -2,9 +2,14 @@
 
 pragma solidity ^0.8.20;
 
+import { ERC2771Storage } from '../storage/ERC2771Storage.sol';
 import { _Context } from './_Context.sol';
+import { _IForwardedMetaTransationContext } from './_IForwardedMetaTransationContext.sol';
 
-abstract contract _ForwardedMetaTransationContext is _Context {
+abstract contract _ForwardedMetaTransationContext is
+    _IForwardedMetaTransationContext,
+    _Context
+{
     /**
      * @inheritdoc _Context
      * @dev sender is read from the calldata context suffix
@@ -16,7 +21,7 @@ abstract contract _ForwardedMetaTransationContext is _Context {
         override
         returns (address msgSender)
     {
-        if (msg.sender == address(this)) {
+        if (_isTrustedForwarder(msg.sender)) {
             msgSender = address(
                 bytes20(msg.data[msg.data.length - _calldataSuffixLength():])
             );
@@ -35,7 +40,7 @@ abstract contract _ForwardedMetaTransationContext is _Context {
         override
         returns (bytes calldata msgData)
     {
-        if (msg.sender == address(this)) {
+        if (_isTrustedForwarder(msg.sender)) {
             msgData = msg.data[:msg.data.length - _calldataSuffixLength()];
         } else {
             msgData = super._msgData();
@@ -55,4 +60,13 @@ abstract contract _ForwardedMetaTransationContext is _Context {
     {
         length = 20;
     }
+
+    function _isTrustedForwarder(
+        address account
+    ) internal view virtual returns (bool trustedStatus) {
+        return
+            ERC2771Storage
+                .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
+                .trustedForwarders[account];
+    }
 }
diff --git a/contracts/utils/_IForwardedMetaTransationContext.sol b/contracts/utils/_IForwardedMetaTransationContext.sol
index 4b63e80d7..f44c09c17 100644
--- a/contracts/utils/_IForwardedMetaTransationContext.sol
+++ b/contracts/utils/_IForwardedMetaTransationContext.sol
@@ -2,6 +2,7 @@
 
 pragma solidity ^0.8.20;
 
+import { _IERC2771 } from '../interfaces/_IERC2771.sol';
 import { _IContext } from './_IContext.sol';
 
-interface _IForwardedMetaTransationContext is _IContext {}
+interface _IForwardedMetaTransationContext is _IContext, _IERC2771 {}

From d71154c35680bf6a73c9b1013562dc404e0bb532 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 14:25:32 -0600
Subject: [PATCH 17/33] add comments to IERC2771

---
 contracts/interfaces/IERC2771.sol                  | 13 ++++++++++++-
 contracts/utils/ForwardedMetaTransationContext.sol |  4 ++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/contracts/interfaces/IERC2771.sol b/contracts/interfaces/IERC2771.sol
index 5a6a1826f..ead7e2f2f 100644
--- a/contracts/interfaces/IERC2771.sol
+++ b/contracts/interfaces/IERC2771.sol
@@ -4,6 +4,17 @@ pragma solidity ^0.8.20;
 
 import { _IERC2771 } from './_IERC2771.sol';
 
+/**
+ * @title ERC2771 interface
+ * @dev see https://eips.ethereum.org/EIPS/eip-2771
+ */
 interface IERC2771 is _IERC2771 {
-    function isTrustedForwarder(address forwarder) external view returns (bool);
+    /**
+     * @notice query whether account is a trusted ERC2771 forwarder
+     * @param account address to query
+     * @return trustedStatus whether account is a trusted forwarder
+     */
+    function isTrustedForwarder(
+        address account
+    ) external view returns (bool trustedStatus);
 }
diff --git a/contracts/utils/ForwardedMetaTransationContext.sol b/contracts/utils/ForwardedMetaTransationContext.sol
index 5a232a78b..fdbdcb51b 100644
--- a/contracts/utils/ForwardedMetaTransationContext.sol
+++ b/contracts/utils/ForwardedMetaTransationContext.sol
@@ -2,6 +2,7 @@
 
 pragma solidity ^0.8.20;
 
+import { IERC2771 } from '../interfaces/IERC2771.sol';
 import { IForwardedMetaTransationContext } from './IForwardedMetaTransationContext.sol';
 import { _ForwardedMetaTransationContext } from './_ForwardedMetaTransationContext.sol';
 
@@ -9,6 +10,9 @@ abstract contract ForwardedMetaTransationContext is
     IForwardedMetaTransationContext,
     _ForwardedMetaTransationContext
 {
+    /**
+     * @inheritdoc IERC2771
+     */
     function isTrustedForwarder(
         address account
     ) external view returns (bool trustedStatus) {

From 1cb92ff4fe081cc7800fc73a3a592fcc0d6d1663 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 14:44:24 -0600
Subject: [PATCH 18/33] check data length before returning context

---
 .../utils/_ForwardedMetaTransationContext.sol | 22 ++++++++++++++-----
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/contracts/utils/_ForwardedMetaTransationContext.sol b/contracts/utils/_ForwardedMetaTransationContext.sol
index aa0fba912..f1858b5c9 100644
--- a/contracts/utils/_ForwardedMetaTransationContext.sol
+++ b/contracts/utils/_ForwardedMetaTransationContext.sol
@@ -21,10 +21,15 @@ abstract contract _ForwardedMetaTransationContext is
         override
         returns (address msgSender)
     {
-        if (_isTrustedForwarder(msg.sender)) {
-            msgSender = address(
-                bytes20(msg.data[msg.data.length - _calldataSuffixLength():])
-            );
+        uint256 dataLength = msg.data.length;
+        uint256 suffixLength = _calldataSuffixLength();
+
+        if (dataLength >= suffixLength && _isTrustedForwarder(msg.sender)) {
+            unchecked {
+                msgSender = address(
+                    bytes20(msg.data[dataLength - suffixLength:])
+                );
+            }
         } else {
             msgSender = super._msgSender();
         }
@@ -40,8 +45,13 @@ abstract contract _ForwardedMetaTransationContext is
         override
         returns (bytes calldata msgData)
     {
-        if (_isTrustedForwarder(msg.sender)) {
-            msgData = msg.data[:msg.data.length - _calldataSuffixLength()];
+        uint256 dataLength = msg.data.length;
+        uint256 suffixLength = _calldataSuffixLength();
+
+        if (dataLength >= suffixLength && _isTrustedForwarder(msg.sender)) {
+            unchecked {
+                msgData = msg.data[:dataLength - suffixLength];
+            }
         } else {
             msgData = super._msgData();
         }

From 0466d01f9f575db3b3811550d5f5429a74ecab71 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 15:47:13 -0600
Subject: [PATCH 19/33] add note about non-revert case and NatSpec comments

---
 contracts/utils/_ForwardedMetaTransationContext.sol | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/contracts/utils/_ForwardedMetaTransationContext.sol b/contracts/utils/_ForwardedMetaTransationContext.sol
index f1858b5c9..59bfd4565 100644
--- a/contracts/utils/_ForwardedMetaTransationContext.sol
+++ b/contracts/utils/_ForwardedMetaTransationContext.sol
@@ -24,6 +24,9 @@ abstract contract _ForwardedMetaTransationContext is
         uint256 dataLength = msg.data.length;
         uint256 suffixLength = _calldataSuffixLength();
 
+        // ideally this would revert when dataLength < suffixLength and sender is a trusted forwarder
+        // but because _isTrustedForwarder reads from storage, it should be called only when necessary
+
         if (dataLength >= suffixLength && _isTrustedForwarder(msg.sender)) {
             unchecked {
                 msgSender = address(
@@ -48,6 +51,9 @@ abstract contract _ForwardedMetaTransationContext is
         uint256 dataLength = msg.data.length;
         uint256 suffixLength = _calldataSuffixLength();
 
+        // ideally this would revert when dataLength < suffixLength and sender is a trusted forwarder
+        // but because _isTrustedForwarder reads from storage, it should be called only when necessary
+
         if (dataLength >= suffixLength && _isTrustedForwarder(msg.sender)) {
             unchecked {
                 msgData = msg.data[:dataLength - suffixLength];
@@ -71,6 +77,11 @@ abstract contract _ForwardedMetaTransationContext is
         length = 20;
     }
 
+    /**
+     * @notice query whether account is a trusted ERC2771 forwarder
+     * @param account address to query
+     * @return trustedStatus whether account is a trusted forwarder
+     */
     function _isTrustedForwarder(
         address account
     ) internal view virtual returns (bool trustedStatus) {

From 9290760eb7e9177c3434b8873c619f04a6717723 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 19:26:59 -0600
Subject: [PATCH 20/33] consider only contracts to be trusted forwarders

---
 contracts/utils/_ForwardedMetaTransationContext.sol | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/contracts/utils/_ForwardedMetaTransationContext.sol b/contracts/utils/_ForwardedMetaTransationContext.sol
index 59bfd4565..783da7f9b 100644
--- a/contracts/utils/_ForwardedMetaTransationContext.sol
+++ b/contracts/utils/_ForwardedMetaTransationContext.sol
@@ -3,6 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { ERC2771Storage } from '../storage/ERC2771Storage.sol';
+import { AddressUtils } from './AddressUtils.sol';
 import { _Context } from './_Context.sol';
 import { _IForwardedMetaTransationContext } from './_IForwardedMetaTransationContext.sol';
 
@@ -10,6 +11,8 @@ abstract contract _ForwardedMetaTransationContext is
     _IForwardedMetaTransationContext,
     _Context
 {
+    using AddressUtils for address;
+
     /**
      * @inheritdoc _Context
      * @dev sender is read from the calldata context suffix
@@ -79,13 +82,15 @@ abstract contract _ForwardedMetaTransationContext is
 
     /**
      * @notice query whether account is a trusted ERC2771 forwarder
+     * @dev only contracts can be considered trusted forwarders
      * @param account address to query
      * @return trustedStatus whether account is a trusted forwarder
      */
     function _isTrustedForwarder(
         address account
     ) internal view virtual returns (bool trustedStatus) {
-        return
+        trustedStatus =
+            account.isContract() &&
             ERC2771Storage
                 .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
                 .trustedForwarders[account];

From 26c7c1b5009f7528b98e360e024d5b27d827e946 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 19:45:07 -0600
Subject: [PATCH 21/33] add trusted forwarder status accessors

---
 .../utils/_ForwardedMetaTransationContext.sol | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/contracts/utils/_ForwardedMetaTransationContext.sol b/contracts/utils/_ForwardedMetaTransationContext.sol
index 783da7f9b..998af3fb8 100644
--- a/contracts/utils/_ForwardedMetaTransationContext.sol
+++ b/contracts/utils/_ForwardedMetaTransationContext.sol
@@ -13,6 +13,8 @@ abstract contract _ForwardedMetaTransationContext is
 {
     using AddressUtils for address;
 
+    error ForwardedMetaTransactionContext__TrustedForwarderMustBeContract();
+
     /**
      * @inheritdoc _Context
      * @dev sender is read from the calldata context suffix
@@ -95,4 +97,28 @@ abstract contract _ForwardedMetaTransationContext is
                 .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
                 .trustedForwarders[account];
     }
+
+    /**
+     * @notice grant trusted forwarder status to account
+     * @param account account whose trusted forwarder status to grant
+     */
+    function _addTrustedForwarder(address account) internal virtual {
+        // exception for address(this) allows a contract to set itself as a trusted forwarder in its constructor
+        if (!account.isContract() && account != address(this))
+            revert ForwardedMetaTransactionContext__TrustedForwarderMustBeContract();
+
+        ERC2771Storage
+            .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
+            .trustedForwarders[account] = true;
+    }
+
+    /**
+     * @notice revoke trusted forwarder status from account
+     * @param account account whose trusted forwarder status to revoke
+     */
+    function _removeTrustedForwarder(address account) internal virtual {
+        delete ERC2771Storage
+            .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
+            .trustedForwarders[account];
+    }
 }

From 3904c441f42ca1b3689941ffaecff44f5844c104 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 21:40:51 -0600
Subject: [PATCH 22/33] add external Context contract

---
 contracts/utils/Context.sol                   |  8 ++++
 .../utils/ForwardedMetaTransationContext.sol  | 44 ++++++++++++++++++-
 contracts/utils/IContext.sol                  |  7 +++
 .../utils/IForwardedMetaTransationContext.sol |  2 +
 4 files changed, 60 insertions(+), 1 deletion(-)
 create mode 100644 contracts/utils/Context.sol
 create mode 100644 contracts/utils/IContext.sol

diff --git a/contracts/utils/Context.sol b/contracts/utils/Context.sol
new file mode 100644
index 000000000..4b71c514a
--- /dev/null
+++ b/contracts/utils/Context.sol
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { IContext } from './IContext.sol';
+import { _Context } from './_Context.sol';
+
+abstract contract Context is IContext, _Context {}
diff --git a/contracts/utils/ForwardedMetaTransationContext.sol b/contracts/utils/ForwardedMetaTransationContext.sol
index fdbdcb51b..212fab75a 100644
--- a/contracts/utils/ForwardedMetaTransationContext.sol
+++ b/contracts/utils/ForwardedMetaTransationContext.sol
@@ -3,12 +3,15 @@
 pragma solidity ^0.8.20;
 
 import { IERC2771 } from '../interfaces/IERC2771.sol';
+import { Context } from './Context.sol';
+import { _Context } from './_Context.sol';
 import { IForwardedMetaTransationContext } from './IForwardedMetaTransationContext.sol';
 import { _ForwardedMetaTransationContext } from './_ForwardedMetaTransationContext.sol';
 
 abstract contract ForwardedMetaTransationContext is
     IForwardedMetaTransationContext,
-    _ForwardedMetaTransationContext
+    _ForwardedMetaTransationContext,
+    Context
 {
     /**
      * @inheritdoc IERC2771
@@ -18,4 +21,43 @@ abstract contract ForwardedMetaTransationContext is
     ) external view returns (bool trustedStatus) {
         trustedStatus = _isTrustedForwarder(account);
     }
+
+    /**
+     * @inheritdoc _ForwardedMetaTransationContext
+     */
+    function _msgSender()
+        internal
+        view
+        virtual
+        override(_Context, _ForwardedMetaTransationContext)
+        returns (address msgSender)
+    {
+        msgSender = super._msgSender();
+    }
+
+    /**
+     * @inheritdoc _ForwardedMetaTransationContext
+     */
+    function _msgData()
+        internal
+        view
+        virtual
+        override(_Context, _ForwardedMetaTransationContext)
+        returns (bytes calldata msgData)
+    {
+        msgData = super._msgData();
+    }
+
+    /**
+     * @inheritdoc _ForwardedMetaTransationContext
+     */
+    function _calldataSuffixLength()
+        internal
+        view
+        virtual
+        override(_Context, _ForwardedMetaTransationContext)
+        returns (uint256 length)
+    {
+        length = super._calldataSuffixLength();
+    }
 }
diff --git a/contracts/utils/IContext.sol b/contracts/utils/IContext.sol
new file mode 100644
index 000000000..8cfd70e11
--- /dev/null
+++ b/contracts/utils/IContext.sol
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.20;
+
+import { _IContext } from './_IContext.sol';
+
+interface IContext is _IContext {}
diff --git a/contracts/utils/IForwardedMetaTransationContext.sol b/contracts/utils/IForwardedMetaTransationContext.sol
index ac7c108fa..d9d760be4 100644
--- a/contracts/utils/IForwardedMetaTransationContext.sol
+++ b/contracts/utils/IForwardedMetaTransationContext.sol
@@ -3,9 +3,11 @@
 pragma solidity ^0.8.20;
 
 import { IERC2771 } from '../interfaces/IERC2771.sol';
+import { IContext } from './IContext.sol';
 import { _IForwardedMetaTransationContext } from './_IForwardedMetaTransationContext.sol';
 
 interface IForwardedMetaTransationContext is
     _IForwardedMetaTransationContext,
+    IContext,
     IERC2771
 {}

From 93503008cc2f2bd3025b492e350ef42178db34fb Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 21:41:48 -0600
Subject: [PATCH 23/33] fix contract name

---
 ...ol => ForwardedMetaTransactionContext.sol} | 22 +++++++++----------
 ...l => IForwardedMetaTransactionContext.sol} |  6 ++---
 ...l => _ForwardedMetaTransactionContext.sol} |  6 ++---
 ... => _IForwardedMetaTransactionContext.sol} |  2 +-
 4 files changed, 18 insertions(+), 18 deletions(-)
 rename contracts/utils/{ForwardedMetaTransationContext.sol => ForwardedMetaTransactionContext.sol} (59%)
 rename contracts/utils/{IForwardedMetaTransationContext.sol => IForwardedMetaTransactionContext.sol} (51%)
 rename contracts/utils/{_ForwardedMetaTransationContext.sol => _ForwardedMetaTransactionContext.sol} (95%)
 rename contracts/utils/{_IForwardedMetaTransationContext.sol => _IForwardedMetaTransactionContext.sol} (69%)

diff --git a/contracts/utils/ForwardedMetaTransationContext.sol b/contracts/utils/ForwardedMetaTransactionContext.sol
similarity index 59%
rename from contracts/utils/ForwardedMetaTransationContext.sol
rename to contracts/utils/ForwardedMetaTransactionContext.sol
index 212fab75a..7dc537add 100644
--- a/contracts/utils/ForwardedMetaTransationContext.sol
+++ b/contracts/utils/ForwardedMetaTransactionContext.sol
@@ -5,12 +5,12 @@ pragma solidity ^0.8.20;
 import { IERC2771 } from '../interfaces/IERC2771.sol';
 import { Context } from './Context.sol';
 import { _Context } from './_Context.sol';
-import { IForwardedMetaTransationContext } from './IForwardedMetaTransationContext.sol';
-import { _ForwardedMetaTransationContext } from './_ForwardedMetaTransationContext.sol';
+import { IForwardedMetaTransactionContext } from './IForwardedMetaTransactionContext.sol';
+import { _ForwardedMetaTransactionContext } from './_ForwardedMetaTransactionContext.sol';
 
-abstract contract ForwardedMetaTransationContext is
-    IForwardedMetaTransationContext,
-    _ForwardedMetaTransationContext,
+abstract contract ForwardedMetaTransactionContext is
+    IForwardedMetaTransactionContext,
+    _ForwardedMetaTransactionContext,
     Context
 {
     /**
@@ -23,39 +23,39 @@ abstract contract ForwardedMetaTransationContext is
     }
 
     /**
-     * @inheritdoc _ForwardedMetaTransationContext
+     * @inheritdoc _ForwardedMetaTransactionContext
      */
     function _msgSender()
         internal
         view
         virtual
-        override(_Context, _ForwardedMetaTransationContext)
+        override(_Context, _ForwardedMetaTransactionContext)
         returns (address msgSender)
     {
         msgSender = super._msgSender();
     }
 
     /**
-     * @inheritdoc _ForwardedMetaTransationContext
+     * @inheritdoc _ForwardedMetaTransactionContext
      */
     function _msgData()
         internal
         view
         virtual
-        override(_Context, _ForwardedMetaTransationContext)
+        override(_Context, _ForwardedMetaTransactionContext)
         returns (bytes calldata msgData)
     {
         msgData = super._msgData();
     }
 
     /**
-     * @inheritdoc _ForwardedMetaTransationContext
+     * @inheritdoc _ForwardedMetaTransactionContext
      */
     function _calldataSuffixLength()
         internal
         view
         virtual
-        override(_Context, _ForwardedMetaTransationContext)
+        override(_Context, _ForwardedMetaTransactionContext)
         returns (uint256 length)
     {
         length = super._calldataSuffixLength();
diff --git a/contracts/utils/IForwardedMetaTransationContext.sol b/contracts/utils/IForwardedMetaTransactionContext.sol
similarity index 51%
rename from contracts/utils/IForwardedMetaTransationContext.sol
rename to contracts/utils/IForwardedMetaTransactionContext.sol
index d9d760be4..79e832739 100644
--- a/contracts/utils/IForwardedMetaTransationContext.sol
+++ b/contracts/utils/IForwardedMetaTransactionContext.sol
@@ -4,10 +4,10 @@ pragma solidity ^0.8.20;
 
 import { IERC2771 } from '../interfaces/IERC2771.sol';
 import { IContext } from './IContext.sol';
-import { _IForwardedMetaTransationContext } from './_IForwardedMetaTransationContext.sol';
+import { _IForwardedMetaTransactionContext } from './_IForwardedMetaTransactionContext.sol';
 
-interface IForwardedMetaTransationContext is
-    _IForwardedMetaTransationContext,
+interface IForwardedMetaTransactionContext is
+    _IForwardedMetaTransactionContext,
     IContext,
     IERC2771
 {}
diff --git a/contracts/utils/_ForwardedMetaTransationContext.sol b/contracts/utils/_ForwardedMetaTransactionContext.sol
similarity index 95%
rename from contracts/utils/_ForwardedMetaTransationContext.sol
rename to contracts/utils/_ForwardedMetaTransactionContext.sol
index 998af3fb8..ecfd74f1f 100644
--- a/contracts/utils/_ForwardedMetaTransationContext.sol
+++ b/contracts/utils/_ForwardedMetaTransactionContext.sol
@@ -5,10 +5,10 @@ pragma solidity ^0.8.20;
 import { ERC2771Storage } from '../storage/ERC2771Storage.sol';
 import { AddressUtils } from './AddressUtils.sol';
 import { _Context } from './_Context.sol';
-import { _IForwardedMetaTransationContext } from './_IForwardedMetaTransationContext.sol';
+import { _IForwardedMetaTransactionContext } from './_IForwardedMetaTransactionContext.sol';
 
-abstract contract _ForwardedMetaTransationContext is
-    _IForwardedMetaTransationContext,
+abstract contract _ForwardedMetaTransactionContext is
+    _IForwardedMetaTransactionContext,
     _Context
 {
     using AddressUtils for address;
diff --git a/contracts/utils/_IForwardedMetaTransationContext.sol b/contracts/utils/_IForwardedMetaTransactionContext.sol
similarity index 69%
rename from contracts/utils/_IForwardedMetaTransationContext.sol
rename to contracts/utils/_IForwardedMetaTransactionContext.sol
index f44c09c17..861b3f57e 100644
--- a/contracts/utils/_IForwardedMetaTransationContext.sol
+++ b/contracts/utils/_IForwardedMetaTransactionContext.sol
@@ -5,4 +5,4 @@ pragma solidity ^0.8.20;
 import { _IERC2771 } from '../interfaces/_IERC2771.sol';
 import { _IContext } from './_IContext.sol';
 
-interface _IForwardedMetaTransationContext is _IContext, _IERC2771 {}
+interface _IForwardedMetaTransactionContext is _IContext, _IERC2771 {}

From 0d4aa5ac2b0e8f951a294caf38c9116d0ff9e2c0 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 22:25:34 -0600
Subject: [PATCH 24/33] test Context contract

---
 test/utils/Context.ts | 58 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 test/utils/Context.ts

diff --git a/test/utils/Context.ts b/test/utils/Context.ts
new file mode 100644
index 000000000..3978cc5de
--- /dev/null
+++ b/test/utils/Context.ts
@@ -0,0 +1,58 @@
+import { SignerWithAddress } from '@nomicfoundation/hardhat-ethers/signers';
+import { $Context, $Context__factory } from '@solidstate/typechain-types';
+import { expect } from 'chai';
+import { ethers } from 'hardhat';
+
+describe('Context', () => {
+  let instance: $Context;
+  let deployer: SignerWithAddress;
+
+  beforeEach(async () => {
+    [deployer] = await ethers.getSigners();
+    instance = await new $Context__factory(deployer).deploy();
+  });
+
+  describe('__internal', () => {
+    describe('#_msgSender()', () => {
+      it('returns message sender', async () => {
+        const tx = await instance.$_msgSender.populateTransaction();
+
+        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
+
+        const result = await deployer.call(tx);
+
+        const decoded = instance.interface.decodeFunctionResult(
+          '$_msgSender',
+          result,
+        );
+
+        expect(decoded).to.deep.equal([await deployer.getAddress()]);
+      });
+    });
+
+    describe('#_msgData()', () => {
+      it('returns complete message data', async () => {
+        const tx = await instance.$_msgData.populateTransaction();
+
+        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
+
+        // message data is returned as received, demonstrating the malleability of msg.data
+
+        const result = await deployer.call(tx);
+
+        const decoded = instance.interface.decodeFunctionResult(
+          '$_msgData',
+          result,
+        );
+
+        expect(decoded).to.deep.equal([tx.data]);
+      });
+    });
+
+    describe('#_calldataSuffixLength()', () => {
+      it('returns 0', async () => {
+        expect(await instance.$_calldataSuffixLength.staticCall()).to.equal(0n);
+      });
+    });
+  });
+});

From 02f62f98c8e1c271ef842305fb4b284cbeecc6c0 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 22:47:19 -0600
Subject: [PATCH 25/33] test ForwardedMetaTransactionContext contract

---
 test/utils/Context.ts                         |   4 -
 test/utils/ForwardedMetaTransactionContext.ts | 154 ++++++++++++++++++
 2 files changed, 154 insertions(+), 4 deletions(-)
 create mode 100644 test/utils/ForwardedMetaTransactionContext.ts

diff --git a/test/utils/Context.ts b/test/utils/Context.ts
index 3978cc5de..872a4f756 100644
--- a/test/utils/Context.ts
+++ b/test/utils/Context.ts
@@ -16,11 +16,9 @@ describe('Context', () => {
     describe('#_msgSender()', () => {
       it('returns message sender', async () => {
         const tx = await instance.$_msgSender.populateTransaction();
-
         tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
 
         const result = await deployer.call(tx);
-
         const decoded = instance.interface.decodeFunctionResult(
           '$_msgSender',
           result,
@@ -33,13 +31,11 @@ describe('Context', () => {
     describe('#_msgData()', () => {
       it('returns complete message data', async () => {
         const tx = await instance.$_msgData.populateTransaction();
-
         tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
 
         // message data is returned as received, demonstrating the malleability of msg.data
 
         const result = await deployer.call(tx);
-
         const decoded = instance.interface.decodeFunctionResult(
           '$_msgData',
           result,
diff --git a/test/utils/ForwardedMetaTransactionContext.ts b/test/utils/ForwardedMetaTransactionContext.ts
new file mode 100644
index 000000000..67e2ac88f
--- /dev/null
+++ b/test/utils/ForwardedMetaTransactionContext.ts
@@ -0,0 +1,154 @@
+import { SignerWithAddress } from '@nomicfoundation/hardhat-ethers/signers';
+import {
+  $ForwardedMetaTransactionContext,
+  $ForwardedMetaTransactionContext__factory,
+} from '@solidstate/typechain-types';
+import { expect } from 'chai';
+import { ethers } from 'hardhat';
+
+describe('ForwardedMe$ForwardedMetaTransactionContext', () => {
+  let instance: $ForwardedMetaTransactionContext;
+  let deployer: SignerWithAddress;
+
+  beforeEach(async () => {
+    [deployer] = await ethers.getSigners();
+    instance = await new $ForwardedMetaTransactionContext__factory(
+      deployer,
+    ).deploy();
+  });
+
+  // TODO: spec
+
+  describe('__internal', () => {
+    describe('#_msgSender()', () => {
+      it('returns message sender is sender is not trusted forwarder', async () => {
+        const tx = await instance.$_msgSender.populateTransaction();
+        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
+
+        const result = await deployer.call(tx);
+        const decoded = instance.interface.decodeFunctionResult(
+          '$_msgSender',
+          result,
+        );
+
+        expect(decoded).to.deep.equal([await deployer.getAddress()]);
+      });
+
+      it('returns forwarded sender if sender is trusted forwarder', async () => {
+        const trustedForwarder = await ethers.getImpersonatedSigner(
+          await instance.getAddress(),
+        );
+        await instance.$_addTrustedForwarder(
+          await trustedForwarder.getAddress(),
+        );
+
+        const forwardedAddress = ethers.hexlify(ethers.randomBytes(20));
+
+        const tx = await instance.$_msgSender.populateTransaction();
+        tx.data = ethers.concat([tx.data, forwardedAddress]);
+
+        const result = await trustedForwarder.call(tx);
+        const decoded = instance.interface.decodeFunctionResult(
+          '$_msgSender',
+          result,
+        );
+
+        expect(decoded).to.deep.equal([forwardedAddress]);
+      });
+    });
+
+    describe('#_msgData()', () => {
+      it('returns complete message data if sender is not trusted forwarder', async () => {
+        const tx = await instance.$_msgData.populateTransaction();
+        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
+
+        // message data is returned as received, demonstrating the malleability of msg.data
+
+        const result = await deployer.call(tx);
+        const decoded = instance.interface.decodeFunctionResult(
+          '$_msgData',
+          result,
+        );
+
+        expect(decoded).to.deep.equal([tx.data]);
+      });
+
+      it('returns message data without suffix if sender is trusted forwarder', async () => {
+        const trustedForwarder = await ethers.getImpersonatedSigner(
+          await instance.getAddress(),
+        );
+        await instance.$_addTrustedForwarder(
+          await trustedForwarder.getAddress(),
+        );
+
+        const tx = await instance.$_msgData.populateTransaction();
+        const nonSuffixedData = tx.data;
+        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
+
+        // message data is returned as received, demonstrating the malleability of msg.data
+
+        const result = await trustedForwarder.call(tx);
+        const decoded = instance.interface.decodeFunctionResult(
+          '$_msgData',
+          result,
+        );
+
+        expect(decoded).to.deep.equal([nonSuffixedData]);
+      });
+    });
+
+    describe('#_calldataSuffixLength()', () => {
+      it('returns 20', async () => {
+        expect(await instance.$_calldataSuffixLength.staticCall()).to.equal(
+          20n,
+        );
+      });
+    });
+
+    describe('#_isTrustedForwarder(address)', () => {
+      it('returns trusted forwarder status of account', async () => {
+        expect(await instance.$_isTrustedForwarder(await deployer.getAddress()))
+          .to.be.false;
+        expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
+          .to.be.false;
+
+        await instance.$_addTrustedForwarder(await instance.getAddress());
+
+        expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
+          .to.be.true;
+      });
+    });
+
+    describe('#_addTrustedForwarder(address)', () => {
+      it('grants trusted forwarder status to account', async () => {
+        await instance.$_addTrustedForwarder(await instance.getAddress());
+
+        expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
+          .to.be.true;
+      });
+
+      describe('reverts if', () => {
+        it('account is not a contract', async () => {
+          // this is enforced via a code check
+          // there's an exception for address(this), but this is difficult to test here
+          await expect(
+            instance.$_addTrustedForwarder(ethers.ZeroAddress),
+          ).to.be.revertedWithCustomError(
+            instance,
+            'ForwardedMetaTransactionContext__TrustedForwarderMustBeContract',
+          );
+        });
+      });
+    });
+
+    describe('#_removeTrustedForwarder(address)', () => {
+      it('revokes trusted forwarder status from account', async () => {
+        await instance.$_addTrustedForwarder(await instance.getAddress());
+        await instance.$_removeTrustedForwarder(await instance.getAddress());
+
+        expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
+          .to.be.false;
+      });
+    });
+  });
+});

From c30c631a07748e97c08a84d0d3cecaf25f0a4579 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Tue, 18 Mar 2025 23:01:37 -0600
Subject: [PATCH 26/33] move context contracts to meta directory

---
 contracts/access/access_control/_AccessControl.sol              | 2 +-
 contracts/access/access_control/_IAccessControl.sol             | 2 +-
 contracts/access/ownable/_IOwnable.sol                          | 2 +-
 contracts/access/ownable/_Ownable.sol                           | 2 +-
 contracts/{utils => meta}/Context.sol                           | 0
 contracts/{utils => meta}/ForwardedMetaTransactionContext.sol   | 0
 contracts/{utils => meta}/IContext.sol                          | 0
 contracts/{utils => meta}/IForwardedMetaTransactionContext.sol  | 0
 contracts/{utils => meta}/_Context.sol                          | 0
 contracts/{utils => meta}/_ForwardedMetaTransactionContext.sol  | 2 +-
 contracts/{utils => meta}/_IContext.sol                         | 0
 contracts/{utils => meta}/_IForwardedMetaTransactionContext.sol | 0
 contracts/security/partially_pausable/_IPartiallyPausable.sol   | 2 +-
 contracts/security/partially_pausable/_PartiallyPausable.sol    | 2 +-
 contracts/security/pausable/_IPausable.sol                      | 2 +-
 contracts/security/pausable/_Pausable.sol                       | 2 +-
 contracts/token/fungible/_FungibleToken.sol                     | 2 +-
 contracts/token/fungible/_IFungibleToken.sol                    | 2 +-
 contracts/token/multi/_IMultiToken.sol                          | 2 +-
 contracts/token/multi/_MultiToken.sol                           | 2 +-
 contracts/token/non_fungible/_INonFungibleToken.sol             | 2 +-
 contracts/token/non_fungible/_NonFungibleToken.sol              | 2 +-
 22 files changed, 15 insertions(+), 15 deletions(-)
 rename contracts/{utils => meta}/Context.sol (100%)
 rename contracts/{utils => meta}/ForwardedMetaTransactionContext.sol (100%)
 rename contracts/{utils => meta}/IContext.sol (100%)
 rename contracts/{utils => meta}/IForwardedMetaTransactionContext.sol (100%)
 rename contracts/{utils => meta}/_Context.sol (100%)
 rename contracts/{utils => meta}/_ForwardedMetaTransactionContext.sol (98%)
 rename contracts/{utils => meta}/_IContext.sol (100%)
 rename contracts/{utils => meta}/_IForwardedMetaTransactionContext.sol (100%)

diff --git a/contracts/access/access_control/_AccessControl.sol b/contracts/access/access_control/_AccessControl.sol
index adad27111..eb891a4ca 100644
--- a/contracts/access/access_control/_AccessControl.sol
+++ b/contracts/access/access_control/_AccessControl.sol
@@ -6,7 +6,7 @@ import { EnumerableSet } from '../../data/EnumerableSet.sol';
 import { AccessControlStorage } from '../../storage/AccessControlStorage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
 import { UintUtils } from '../../utils/UintUtils.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _IAccessControl } from './_IAccessControl.sol';
 
 /**
diff --git a/contracts/access/access_control/_IAccessControl.sol b/contracts/access/access_control/_IAccessControl.sol
index 0c089851c..2813d2480 100644
--- a/contracts/access/access_control/_IAccessControl.sol
+++ b/contracts/access/access_control/_IAccessControl.sol
@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.20;
 
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 /**
  * @title Partial AccessControl interface needed by internal functions
diff --git a/contracts/access/ownable/_IOwnable.sol b/contracts/access/ownable/_IOwnable.sol
index b3ec83597..e9c733804 100644
--- a/contracts/access/ownable/_IOwnable.sol
+++ b/contracts/access/ownable/_IOwnable.sol
@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { _IERC173 } from '../../interfaces/_IERC173.sol';
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 interface _IOwnable is _IERC173, _IContext {
     error Ownable__NotOwner();
diff --git a/contracts/access/ownable/_Ownable.sol b/contracts/access/ownable/_Ownable.sol
index d53c21a90..2f4250b4d 100644
--- a/contracts/access/ownable/_Ownable.sol
+++ b/contracts/access/ownable/_Ownable.sol
@@ -5,7 +5,7 @@ pragma solidity ^0.8.20;
 import { IERC173 } from '../../interfaces/IERC173.sol';
 import { ERC173Storage } from '../../storage/ERC173Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _IOwnable } from './_IOwnable.sol';
 
 abstract contract _Ownable is _IOwnable, _Context {
diff --git a/contracts/utils/Context.sol b/contracts/meta/Context.sol
similarity index 100%
rename from contracts/utils/Context.sol
rename to contracts/meta/Context.sol
diff --git a/contracts/utils/ForwardedMetaTransactionContext.sol b/contracts/meta/ForwardedMetaTransactionContext.sol
similarity index 100%
rename from contracts/utils/ForwardedMetaTransactionContext.sol
rename to contracts/meta/ForwardedMetaTransactionContext.sol
diff --git a/contracts/utils/IContext.sol b/contracts/meta/IContext.sol
similarity index 100%
rename from contracts/utils/IContext.sol
rename to contracts/meta/IContext.sol
diff --git a/contracts/utils/IForwardedMetaTransactionContext.sol b/contracts/meta/IForwardedMetaTransactionContext.sol
similarity index 100%
rename from contracts/utils/IForwardedMetaTransactionContext.sol
rename to contracts/meta/IForwardedMetaTransactionContext.sol
diff --git a/contracts/utils/_Context.sol b/contracts/meta/_Context.sol
similarity index 100%
rename from contracts/utils/_Context.sol
rename to contracts/meta/_Context.sol
diff --git a/contracts/utils/_ForwardedMetaTransactionContext.sol b/contracts/meta/_ForwardedMetaTransactionContext.sol
similarity index 98%
rename from contracts/utils/_ForwardedMetaTransactionContext.sol
rename to contracts/meta/_ForwardedMetaTransactionContext.sol
index ecfd74f1f..2b645f386 100644
--- a/contracts/utils/_ForwardedMetaTransactionContext.sol
+++ b/contracts/meta/_ForwardedMetaTransactionContext.sol
@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { ERC2771Storage } from '../storage/ERC2771Storage.sol';
-import { AddressUtils } from './AddressUtils.sol';
+import { AddressUtils } from '../utils/AddressUtils.sol';
 import { _Context } from './_Context.sol';
 import { _IForwardedMetaTransactionContext } from './_IForwardedMetaTransactionContext.sol';
 
diff --git a/contracts/utils/_IContext.sol b/contracts/meta/_IContext.sol
similarity index 100%
rename from contracts/utils/_IContext.sol
rename to contracts/meta/_IContext.sol
diff --git a/contracts/utils/_IForwardedMetaTransactionContext.sol b/contracts/meta/_IForwardedMetaTransactionContext.sol
similarity index 100%
rename from contracts/utils/_IForwardedMetaTransactionContext.sol
rename to contracts/meta/_IForwardedMetaTransactionContext.sol
diff --git a/contracts/security/partially_pausable/_IPartiallyPausable.sol b/contracts/security/partially_pausable/_IPartiallyPausable.sol
index 1705072c5..80a8fd8d1 100644
--- a/contracts/security/partially_pausable/_IPartiallyPausable.sol
+++ b/contracts/security/partially_pausable/_IPartiallyPausable.sol
@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.20;
 
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 interface _IPartiallyPausable is _IContext {
     error PartiallyPausable__PartiallyPaused();
diff --git a/contracts/security/partially_pausable/_PartiallyPausable.sol b/contracts/security/partially_pausable/_PartiallyPausable.sol
index f510d1334..1d53b97ce 100644
--- a/contracts/security/partially_pausable/_PartiallyPausable.sol
+++ b/contracts/security/partially_pausable/_PartiallyPausable.sol
@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { PausableStorage } from '../../storage/PausableStorage.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _IPartiallyPausable } from './_IPartiallyPausable.sol';
 
 /**
diff --git a/contracts/security/pausable/_IPausable.sol b/contracts/security/pausable/_IPausable.sol
index 1c2dca946..d2eba9a27 100644
--- a/contracts/security/pausable/_IPausable.sol
+++ b/contracts/security/pausable/_IPausable.sol
@@ -2,7 +2,7 @@
 
 pragma solidity ^0.8.20;
 
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 interface _IPausable is _IContext {
     error Pausable__Paused();
diff --git a/contracts/security/pausable/_Pausable.sol b/contracts/security/pausable/_Pausable.sol
index 2e6bf39da..5ee1e7433 100644
--- a/contracts/security/pausable/_Pausable.sol
+++ b/contracts/security/pausable/_Pausable.sol
@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { PausableStorage } from '../../storage/PausableStorage.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _IPausable } from './_IPausable.sol';
 
 /**
diff --git a/contracts/token/fungible/_FungibleToken.sol b/contracts/token/fungible/_FungibleToken.sol
index 440b5ae81..73a6c4ace 100644
--- a/contracts/token/fungible/_FungibleToken.sol
+++ b/contracts/token/fungible/_FungibleToken.sol
@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { ERC20Storage } from '../../storage/ERC20Storage.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _IFungibleToken } from './_IFungibleToken.sol';
 
 /**
diff --git a/contracts/token/fungible/_IFungibleToken.sol b/contracts/token/fungible/_IFungibleToken.sol
index 0757ff671..64cbc1629 100644
--- a/contracts/token/fungible/_IFungibleToken.sol
+++ b/contracts/token/fungible/_IFungibleToken.sol
@@ -3,7 +3,7 @@
 pragma solidity ^0.8.20;
 
 import { _IERC20 } from '../../interfaces/_IERC20.sol';
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 /**
  * @title FungibleToken base interface
diff --git a/contracts/token/multi/_IMultiToken.sol b/contracts/token/multi/_IMultiToken.sol
index 214bc256e..c81d4cb29 100644
--- a/contracts/token/multi/_IMultiToken.sol
+++ b/contracts/token/multi/_IMultiToken.sol
@@ -4,7 +4,7 @@ pragma solidity ^0.8.20;
 
 import { _IERC1155 } from '../../interfaces/_IERC1155.sol';
 import { _IIntrospectable } from '../../introspection/_IIntrospectable.sol';
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 /**
  * @title MultiToken base interface
diff --git a/contracts/token/multi/_MultiToken.sol b/contracts/token/multi/_MultiToken.sol
index cbffd0b3f..dac82e60c 100644
--- a/contracts/token/multi/_MultiToken.sol
+++ b/contracts/token/multi/_MultiToken.sol
@@ -6,7 +6,7 @@ import { IERC1155Receiver } from '../../interfaces/IERC1155Receiver.sol';
 import { _Introspectable } from '../../introspection/_Introspectable.sol';
 import { ERC1155Storage } from '../../storage/ERC1155Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _IMultiToken } from './_IMultiToken.sol';
 
 /**
diff --git a/contracts/token/non_fungible/_INonFungibleToken.sol b/contracts/token/non_fungible/_INonFungibleToken.sol
index bc4de714a..bbc762683 100644
--- a/contracts/token/non_fungible/_INonFungibleToken.sol
+++ b/contracts/token/non_fungible/_INonFungibleToken.sol
@@ -4,7 +4,7 @@ pragma solidity ^0.8.20;
 
 import { _IERC721 } from '../../interfaces/_IERC721.sol';
 import { _IIntrospectable } from '../../introspection/_IIntrospectable.sol';
-import { _IContext } from '../../utils/_IContext.sol';
+import { _IContext } from '../../meta/_IContext.sol';
 
 /**
  * @title NonFungibleToken base interface
diff --git a/contracts/token/non_fungible/_NonFungibleToken.sol b/contracts/token/non_fungible/_NonFungibleToken.sol
index 899d84240..38cff59ae 100644
--- a/contracts/token/non_fungible/_NonFungibleToken.sol
+++ b/contracts/token/non_fungible/_NonFungibleToken.sol
@@ -8,7 +8,7 @@ import { IERC721Receiver } from '../../interfaces/IERC721Receiver.sol';
 import { _Introspectable } from '../../introspection/_Introspectable.sol';
 import { ERC721Storage } from '../../storage/ERC721Storage.sol';
 import { AddressUtils } from '../../utils/AddressUtils.sol';
-import { _Context } from '../../utils/_Context.sol';
+import { _Context } from '../../meta/_Context.sol';
 import { _INonFungibleToken } from './_INonFungibleToken.sol';
 
 /**

From 3c3a05d38aba142001e3edabe9b959c4511d86ee Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Thu, 20 Mar 2025 10:38:56 -0600
Subject: [PATCH 27/33] move context tests to meta directory

---
 test/{utils => meta}/Context.ts                         | 0
 test/{utils => meta}/ForwardedMetaTransactionContext.ts | 0
 2 files changed, 0 insertions(+), 0 deletions(-)
 rename test/{utils => meta}/Context.ts (100%)
 rename test/{utils => meta}/ForwardedMetaTransactionContext.ts (100%)

diff --git a/test/utils/Context.ts b/test/meta/Context.ts
similarity index 100%
rename from test/utils/Context.ts
rename to test/meta/Context.ts
diff --git a/test/utils/ForwardedMetaTransactionContext.ts b/test/meta/ForwardedMetaTransactionContext.ts
similarity index 100%
rename from test/utils/ForwardedMetaTransactionContext.ts
rename to test/meta/ForwardedMetaTransactionContext.ts

From 6da28f69639a478bf5fb2394e1d05683a02ec4a8 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Thu, 20 Mar 2025 10:41:58 -0600
Subject: [PATCH 28/33] fix test suite title

---
 test/meta/ForwardedMetaTransactionContext.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/meta/ForwardedMetaTransactionContext.ts b/test/meta/ForwardedMetaTransactionContext.ts
index 67e2ac88f..325ef24d6 100644
--- a/test/meta/ForwardedMetaTransactionContext.ts
+++ b/test/meta/ForwardedMetaTransactionContext.ts
@@ -6,7 +6,7 @@ import {
 import { expect } from 'chai';
 import { ethers } from 'hardhat';
 
-describe('ForwardedMe$ForwardedMetaTransactionContext', () => {
+describe('ForwardedMetaTransactionContext', () => {
   let instance: $ForwardedMetaTransactionContext;
   let deployer: SignerWithAddress;
 

From 8797018208537128d211fab2aa46dcd48c7445f0 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Thu, 20 Mar 2025 11:50:10 -0600
Subject: [PATCH 29/33] add callMetaTransaction test helper

---
 test/meta/ForwardedMetaTransactionContext.ts | 89 +++++++++++---------
 1 file changed, 47 insertions(+), 42 deletions(-)

diff --git a/test/meta/ForwardedMetaTransactionContext.ts b/test/meta/ForwardedMetaTransactionContext.ts
index 325ef24d6..ca7794e6c 100644
--- a/test/meta/ForwardedMetaTransactionContext.ts
+++ b/test/meta/ForwardedMetaTransactionContext.ts
@@ -3,9 +3,28 @@ import {
   $ForwardedMetaTransactionContext,
   $ForwardedMetaTransactionContext__factory,
 } from '@solidstate/typechain-types';
+import { TypedContractMethod } from '@solidstate/typechain-types/common';
 import { expect } from 'chai';
+import { BytesLike } from 'ethers';
 import { ethers } from 'hardhat';
 
+const callMetaTransaction = async (
+  signer: SignerWithAddress,
+  fn: TypedContractMethod<[], [string], 'view'>,
+  data: BytesLike,
+  args: any[] = [],
+) => {
+  const tx = await fn.populateTransaction();
+  tx.data = ethers.concat([tx.data, data]);
+
+  const result = await signer.call(tx);
+
+  return new ethers.Interface([fn.fragment]).decodeFunctionResult(
+    fn.name,
+    result,
+  );
+};
+
 describe('ForwardedMetaTransactionContext', () => {
   let instance: $ForwardedMetaTransactionContext;
   let deployer: SignerWithAddress;
@@ -21,17 +40,14 @@ describe('ForwardedMetaTransactionContext', () => {
 
   describe('__internal', () => {
     describe('#_msgSender()', () => {
-      it('returns message sender is sender is not trusted forwarder', async () => {
-        const tx = await instance.$_msgSender.populateTransaction();
-        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
-
-        const result = await deployer.call(tx);
-        const decoded = instance.interface.decodeFunctionResult(
-          '$_msgSender',
-          result,
-        );
-
-        expect(decoded).to.deep.equal([await deployer.getAddress()]);
+      it('returns message sender if sender is not trusted forwarder', async () => {
+        expect(
+          await callMetaTransaction(
+            deployer,
+            instance.$_msgSender,
+            ethers.randomBytes(20),
+          ),
+        ).to.deep.equal([await deployer.getAddress()]);
       });
 
       it('returns forwarded sender if sender is trusted forwarder', async () => {
@@ -44,33 +60,26 @@ describe('ForwardedMetaTransactionContext', () => {
 
         const forwardedAddress = ethers.hexlify(ethers.randomBytes(20));
 
-        const tx = await instance.$_msgSender.populateTransaction();
-        tx.data = ethers.concat([tx.data, forwardedAddress]);
-
-        const result = await trustedForwarder.call(tx);
-        const decoded = instance.interface.decodeFunctionResult(
-          '$_msgSender',
-          result,
-        );
-
-        expect(decoded).to.deep.equal([forwardedAddress]);
+        expect(
+          await callMetaTransaction(
+            trustedForwarder,
+            instance.$_msgSender,
+            forwardedAddress,
+          ),
+        ).to.deep.equal([forwardedAddress]);
       });
     });
 
     describe('#_msgData()', () => {
       it('returns complete message data if sender is not trusted forwarder', async () => {
-        const tx = await instance.$_msgData.populateTransaction();
-        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
+        const nonSuffixedData = instance.$_msgData.fragment.selector;
+        const data = ethers.randomBytes(20);
 
         // message data is returned as received, demonstrating the malleability of msg.data
 
-        const result = await deployer.call(tx);
-        const decoded = instance.interface.decodeFunctionResult(
-          '$_msgData',
-          result,
-        );
-
-        expect(decoded).to.deep.equal([tx.data]);
+        expect(
+          await callMetaTransaction(deployer, instance.$_msgData, data),
+        ).to.deep.equal([ethers.concat([nonSuffixedData, data])]);
       });
 
       it('returns message data without suffix if sender is trusted forwarder', async () => {
@@ -81,19 +90,15 @@ describe('ForwardedMetaTransactionContext', () => {
           await trustedForwarder.getAddress(),
         );
 
-        const tx = await instance.$_msgData.populateTransaction();
-        const nonSuffixedData = tx.data;
-        tx.data = ethers.concat([tx.data, ethers.randomBytes(20)]);
-
-        // message data is returned as received, demonstrating the malleability of msg.data
-
-        const result = await trustedForwarder.call(tx);
-        const decoded = instance.interface.decodeFunctionResult(
-          '$_msgData',
-          result,
-        );
+        const nonSuffixedData = instance.$_msgData.fragment.selector;
 
-        expect(decoded).to.deep.equal([nonSuffixedData]);
+        expect(
+          await callMetaTransaction(
+            trustedForwarder,
+            instance.$_msgData,
+            ethers.randomBytes(20),
+          ),
+        ).to.deep.equal([nonSuffixedData]);
       });
     });
 

From 9dc06730c8057d4f4adf0c1a3fec9b86a2acd902 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Thu, 20 Mar 2025 12:08:27 -0600
Subject: [PATCH 30/33] enable arguments for callMetaTransaction helper

---
 test/meta/ForwardedMetaTransactionContext.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/meta/ForwardedMetaTransactionContext.ts b/test/meta/ForwardedMetaTransactionContext.ts
index ca7794e6c..a69c12313 100644
--- a/test/meta/ForwardedMetaTransactionContext.ts
+++ b/test/meta/ForwardedMetaTransactionContext.ts
@@ -5,16 +5,16 @@ import {
 } from '@solidstate/typechain-types';
 import { TypedContractMethod } from '@solidstate/typechain-types/common';
 import { expect } from 'chai';
-import { BytesLike } from 'ethers';
+import { BytesLike, ContractMethodArgs } from 'ethers';
 import { ethers } from 'hardhat';
 
 const callMetaTransaction = async (
   signer: SignerWithAddress,
   fn: TypedContractMethod<[], [string], 'view'>,
   data: BytesLike,
-  args: any[] = [],
+  args: ContractMethodArgs<[]> = [],
 ) => {
-  const tx = await fn.populateTransaction();
+  const tx = await fn.populateTransaction(...args);
   tx.data = ethers.concat([tx.data, data]);
 
   const result = await signer.call(tx);

From 1750e80ec94dab52cfc80dac190b14687deae908 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Thu, 20 Mar 2025 13:31:11 -0600
Subject: [PATCH 31/33] test ForwardedMetaTransactionContext case where suffix
 is added but is too short

---
 test/meta/ForwardedMetaTransactionContext.ts | 67 +++++++++++++++++---
 1 file changed, 59 insertions(+), 8 deletions(-)

diff --git a/test/meta/ForwardedMetaTransactionContext.ts b/test/meta/ForwardedMetaTransactionContext.ts
index a69c12313..f457e9463 100644
--- a/test/meta/ForwardedMetaTransactionContext.ts
+++ b/test/meta/ForwardedMetaTransactionContext.ts
@@ -10,7 +10,7 @@ import { ethers } from 'hardhat';
 
 const callMetaTransaction = async (
   signer: SignerWithAddress,
-  fn: TypedContractMethod<[], [string], 'view'>,
+  fn: TypedContractMethod<[], [string], 'nonpayable' | 'payable' | 'view'>,
   data: BytesLike,
   args: ContractMethodArgs<[]> = [],
 ) => {
@@ -40,6 +40,25 @@ describe('ForwardedMetaTransactionContext', () => {
 
   describe('__internal', () => {
     describe('#_msgSender()', () => {
+      it('returns forwarded sender if sender is trusted forwarder', async () => {
+        const trustedForwarder = await ethers.getImpersonatedSigner(
+          await instance.getAddress(),
+        );
+        await instance.$_addTrustedForwarder(
+          await trustedForwarder.getAddress(),
+        );
+
+        const forwardedAddress = ethers.hexlify(ethers.randomBytes(20));
+
+        expect(
+          await callMetaTransaction(
+            trustedForwarder,
+            instance.$_msgSender,
+            forwardedAddress,
+          ),
+        ).to.deep.equal([forwardedAddress]);
+      });
+
       it('returns message sender if sender is not trusted forwarder', async () => {
         expect(
           await callMetaTransaction(
@@ -50,7 +69,7 @@ describe('ForwardedMetaTransactionContext', () => {
         ).to.deep.equal([await deployer.getAddress()]);
       });
 
-      it('returns forwarded sender if sender is trusted forwarder', async () => {
+      it('returns message sender if message data length is less than suffix length', async () => {
         const trustedForwarder = await ethers.getImpersonatedSigner(
           await instance.getAddress(),
         );
@@ -58,19 +77,43 @@ describe('ForwardedMetaTransactionContext', () => {
           await trustedForwarder.getAddress(),
         );
 
-        const forwardedAddress = ethers.hexlify(ethers.randomBytes(20));
+        // account for 4-byte selector when calculting suffix length
+        const suffix = ethers.randomBytes(
+          Number(
+            (await instance.$_calldataSuffixLength.staticCall()) - 4n - 1n,
+          ),
+        );
 
         expect(
           await callMetaTransaction(
             trustedForwarder,
             instance.$_msgSender,
-            forwardedAddress,
+            suffix,
           ),
-        ).to.deep.equal([forwardedAddress]);
+        ).to.deep.equal([await trustedForwarder.getAddress()]);
       });
     });
 
     describe('#_msgData()', () => {
+      it('returns message data without suffix if sender is trusted forwarder', async () => {
+        const trustedForwarder = await ethers.getImpersonatedSigner(
+          await instance.getAddress(),
+        );
+        await instance.$_addTrustedForwarder(
+          await trustedForwarder.getAddress(),
+        );
+
+        const nonSuffixedData = instance.$_msgData.fragment.selector;
+
+        expect(
+          await callMetaTransaction(
+            trustedForwarder,
+            instance.$_msgData,
+            ethers.randomBytes(20),
+          ),
+        ).to.deep.equal([nonSuffixedData]);
+      });
+
       it('returns complete message data if sender is not trusted forwarder', async () => {
         const nonSuffixedData = instance.$_msgData.fragment.selector;
         const data = ethers.randomBytes(20);
@@ -82,7 +125,7 @@ describe('ForwardedMetaTransactionContext', () => {
         ).to.deep.equal([ethers.concat([nonSuffixedData, data])]);
       });
 
-      it('returns message data without suffix if sender is trusted forwarder', async () => {
+      it('returns complete message data if message data length is less than suffix length', async () => {
         const trustedForwarder = await ethers.getImpersonatedSigner(
           await instance.getAddress(),
         );
@@ -91,14 +134,22 @@ describe('ForwardedMetaTransactionContext', () => {
         );
 
         const nonSuffixedData = instance.$_msgData.fragment.selector;
+        // account for 4-byte selector when calculting suffix length
+        const suffix = ethers.randomBytes(
+          Number(
+            (await instance.$_calldataSuffixLength.staticCall()) - 4n - 1n,
+          ),
+        );
+
+        // message data is returned as received, demonstrating the malleability of msg.data
 
         expect(
           await callMetaTransaction(
             trustedForwarder,
             instance.$_msgData,
-            ethers.randomBytes(20),
+            suffix,
           ),
-        ).to.deep.equal([nonSuffixedData]);
+        ).to.deep.equal([ethers.concat([nonSuffixedData, suffix])]);
       });
     });
 

From 059c414a42fc05d165ae96f1ecd1f569a158a470 Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Sat, 22 Mar 2025 11:48:19 -0600
Subject: [PATCH 32/33] allow EOA trusted forwarders

---
 .../meta/_ForwardedMetaTransactionContext.sol | 14 +---
 test/meta/ForwardedMetaTransactionContext.ts  | 78 ++++++-------------
 2 files changed, 27 insertions(+), 65 deletions(-)

diff --git a/contracts/meta/_ForwardedMetaTransactionContext.sol b/contracts/meta/_ForwardedMetaTransactionContext.sol
index 2b645f386..ce5c0724a 100644
--- a/contracts/meta/_ForwardedMetaTransactionContext.sol
+++ b/contracts/meta/_ForwardedMetaTransactionContext.sol
@@ -13,8 +13,6 @@ abstract contract _ForwardedMetaTransactionContext is
 {
     using AddressUtils for address;
 
-    error ForwardedMetaTransactionContext__TrustedForwarderMustBeContract();
-
     /**
      * @inheritdoc _Context
      * @dev sender is read from the calldata context suffix
@@ -91,11 +89,9 @@ abstract contract _ForwardedMetaTransactionContext is
     function _isTrustedForwarder(
         address account
     ) internal view virtual returns (bool trustedStatus) {
-        trustedStatus =
-            account.isContract() &&
-            ERC2771Storage
-                .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
-                .trustedForwarders[account];
+        trustedStatus = ERC2771Storage
+            .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
+            .trustedForwarders[account];
     }
 
     /**
@@ -103,10 +99,6 @@ abstract contract _ForwardedMetaTransactionContext is
      * @param account account whose trusted forwarder status to grant
      */
     function _addTrustedForwarder(address account) internal virtual {
-        // exception for address(this) allows a contract to set itself as a trusted forwarder in its constructor
-        if (!account.isContract() && account != address(this))
-            revert ForwardedMetaTransactionContext__TrustedForwarderMustBeContract();
-
         ERC2771Storage
             .layout(ERC2771Storage.DEFAULT_STORAGE_SLOT)
             .trustedForwarders[account] = true;
diff --git a/test/meta/ForwardedMetaTransactionContext.ts b/test/meta/ForwardedMetaTransactionContext.ts
index f457e9463..234115636 100644
--- a/test/meta/ForwardedMetaTransactionContext.ts
+++ b/test/meta/ForwardedMetaTransactionContext.ts
@@ -27,13 +27,18 @@ const callMetaTransaction = async (
 
 describe('ForwardedMetaTransactionContext', () => {
   let instance: $ForwardedMetaTransactionContext;
-  let deployer: SignerWithAddress;
+  let trustedForwarder: SignerWithAddress;
+  let nonTrustedForwarder: SignerWithAddress;
 
   beforeEach(async () => {
-    [deployer] = await ethers.getSigners();
+    let deployer;
+    [deployer, trustedForwarder, nonTrustedForwarder] =
+      await ethers.getSigners();
     instance = await new $ForwardedMetaTransactionContext__factory(
       deployer,
     ).deploy();
+
+    await instance.$_addTrustedForwarder(await trustedForwarder.getAddress());
   });
 
   // TODO: spec
@@ -41,13 +46,6 @@ describe('ForwardedMetaTransactionContext', () => {
   describe('__internal', () => {
     describe('#_msgSender()', () => {
       it('returns forwarded sender if sender is trusted forwarder', async () => {
-        const trustedForwarder = await ethers.getImpersonatedSigner(
-          await instance.getAddress(),
-        );
-        await instance.$_addTrustedForwarder(
-          await trustedForwarder.getAddress(),
-        );
-
         const forwardedAddress = ethers.hexlify(ethers.randomBytes(20));
 
         expect(
@@ -62,21 +60,14 @@ describe('ForwardedMetaTransactionContext', () => {
       it('returns message sender if sender is not trusted forwarder', async () => {
         expect(
           await callMetaTransaction(
-            deployer,
+            nonTrustedForwarder,
             instance.$_msgSender,
             ethers.randomBytes(20),
           ),
-        ).to.deep.equal([await deployer.getAddress()]);
+        ).to.deep.equal([await nonTrustedForwarder.getAddress()]);
       });
 
       it('returns message sender if message data length is less than suffix length', async () => {
-        const trustedForwarder = await ethers.getImpersonatedSigner(
-          await instance.getAddress(),
-        );
-        await instance.$_addTrustedForwarder(
-          await trustedForwarder.getAddress(),
-        );
-
         // account for 4-byte selector when calculting suffix length
         const suffix = ethers.randomBytes(
           Number(
@@ -96,13 +87,6 @@ describe('ForwardedMetaTransactionContext', () => {
 
     describe('#_msgData()', () => {
       it('returns message data without suffix if sender is trusted forwarder', async () => {
-        const trustedForwarder = await ethers.getImpersonatedSigner(
-          await instance.getAddress(),
-        );
-        await instance.$_addTrustedForwarder(
-          await trustedForwarder.getAddress(),
-        );
-
         const nonSuffixedData = instance.$_msgData.fragment.selector;
 
         expect(
@@ -121,18 +105,15 @@ describe('ForwardedMetaTransactionContext', () => {
         // message data is returned as received, demonstrating the malleability of msg.data
 
         expect(
-          await callMetaTransaction(deployer, instance.$_msgData, data),
+          await callMetaTransaction(
+            nonTrustedForwarder,
+            instance.$_msgData,
+            data,
+          ),
         ).to.deep.equal([ethers.concat([nonSuffixedData, data])]);
       });
 
       it('returns complete message data if message data length is less than suffix length', async () => {
-        const trustedForwarder = await ethers.getImpersonatedSigner(
-          await instance.getAddress(),
-        );
-        await instance.$_addTrustedForwarder(
-          await trustedForwarder.getAddress(),
-        );
-
         const nonSuffixedData = instance.$_msgData.fragment.selector;
         // account for 4-byte selector when calculting suffix length
         const suffix = ethers.randomBytes(
@@ -163,15 +144,17 @@ describe('ForwardedMetaTransactionContext', () => {
 
     describe('#_isTrustedForwarder(address)', () => {
       it('returns trusted forwarder status of account', async () => {
-        expect(await instance.$_isTrustedForwarder(await deployer.getAddress()))
-          .to.be.false;
-        expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
-          .to.be.false;
-
-        await instance.$_addTrustedForwarder(await instance.getAddress());
+        expect(
+          await instance.$_isTrustedForwarder(
+            await nonTrustedForwarder.getAddress(),
+          ),
+        ).to.be.false;
 
-        expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
-          .to.be.true;
+        expect(
+          await instance.$_isTrustedForwarder(
+            await trustedForwarder.getAddress(),
+          ),
+        ).to.be.true;
       });
     });
 
@@ -182,19 +165,6 @@ describe('ForwardedMetaTransactionContext', () => {
         expect(await instance.$_isTrustedForwarder(await instance.getAddress()))
           .to.be.true;
       });
-
-      describe('reverts if', () => {
-        it('account is not a contract', async () => {
-          // this is enforced via a code check
-          // there's an exception for address(this), but this is difficult to test here
-          await expect(
-            instance.$_addTrustedForwarder(ethers.ZeroAddress),
-          ).to.be.revertedWithCustomError(
-            instance,
-            'ForwardedMetaTransactionContext__TrustedForwarderMustBeContract',
-          );
-        });
-      });
     });
 
     describe('#_removeTrustedForwarder(address)', () => {

From b87a95d4936748b9ca74e3d82ea6a57100c5310b Mon Sep 17 00:00:00 2001
From: Nick Barry <itsnickbarry@protonmail.ch>
Date: Sat, 22 Mar 2025 11:53:40 -0600
Subject: [PATCH 33/33] remove dev note

---
 contracts/meta/_ForwardedMetaTransactionContext.sol | 1 -
 1 file changed, 1 deletion(-)

diff --git a/contracts/meta/_ForwardedMetaTransactionContext.sol b/contracts/meta/_ForwardedMetaTransactionContext.sol
index ce5c0724a..21fe4fa02 100644
--- a/contracts/meta/_ForwardedMetaTransactionContext.sol
+++ b/contracts/meta/_ForwardedMetaTransactionContext.sol
@@ -82,7 +82,6 @@ abstract contract _ForwardedMetaTransactionContext is
 
     /**
      * @notice query whether account is a trusted ERC2771 forwarder
-     * @dev only contracts can be considered trusted forwarders
      * @param account address to query
      * @return trustedStatus whether account is a trusted forwarder
      */