fix: add install-time input validation (TOB-KERNEL-5)

src/policies/CallerPolicy.sol

@@ -28,6 +28,9 @@ import {
  *      If you need to validate who signed, use a signer module instead.
  */
 contract CallerPolicy is PolicyBase, IStatelessValidatorWithSender {
+    error EmptyCallers();
+    error ZeroAddressCaller();
+
     mapping(bytes32 id => mapping(address => Status)) public status;
     /// @notice Maps policy ID => requesting protocol => wallet => whether protocol is allowed
     mapping(bytes32 id => mapping(address caller => mapping(address wallet => bool))) public allowedCaller;
@@ -84,9 +87,9 @@ contract CallerPolicy is PolicyBase, IStatelessValidatorWithSender {
     function _policyOninstall(bytes32 id, bytes calldata _data) internal override {
         require(status[id][msg.sender] == Status.NA, "Already installed");
         address[] memory callers = abi.decode(_data, (address[]));
-        require(callers.length > 0, "Empty callers array");
+        require(callers.length > 0, EmptyCallers());
         for (uint256 i = 0; i < callers.length; i++) {
-            require(callers[i] != address(0), "Zero address caller");
+            require(callers[i] != address(0), ZeroAddressCaller());
             allowedCaller[id][callers[i]][msg.sender] = true;
         }
         status[id][msg.sender] = Status.Live;

src/signers/ECDSASigner.sol

@@ -62,9 +62,9 @@ contract ECDSASigner is SignerBase, IStatelessValidator, IStatelessValidatorWith
 
     function _signerOninstall(bytes32 id, bytes calldata _data) internal override {
         require(signer[id][msg.sender] == address(0), "Already installed");
-        if (_data.length != 20) revert InvalidDataLength();
+        require(_data.length == 20, InvalidDataLength());
         address signerAddr = address(bytes20(_data[0:20]));
-        if (signerAddr == address(0)) revert ZeroAddressSigner();
+        require(signerAddr != address(0), ZeroAddressSigner());
         signer[id][msg.sender] = signerAddr;
     }
 

src/signers/WeightedECDSASigner.sol

@@ -36,6 +36,7 @@ contract WeightedECDSASigner is EIP712, SignerBase, IStatelessValidator, IStatel
         keccak256("Proposal(address account,bytes32 id,bytes callData,uint256 nonce)");
 
     error ZeroWeightSigner();
+    error ThresholdExceedsTotalWeight();
 
     mapping(bytes32 id => mapping(address kernel => WeightedECDSASignerStorage)) public weightedStorage;
     mapping(address guardian => mapping(bytes32 id => mapping(address kernel => GuardianStorage))) public guardian;
@@ -69,6 +70,7 @@ contract WeightedECDSASigner is EIP712, SignerBase, IStatelessValidator, IStatel
             weightedStorage[id][msg.sender].totalWeight += _weights[i];
             emit GuardianAdded(_guardians[i], msg.sender, _weights[i]);
         }
+        require(_threshold <= weightedStorage[id][msg.sender].totalWeight, ThresholdExceedsTotalWeight());
         weightedStorage[id][msg.sender].threshold = _threshold;
     }
 

src/validators/ECDSAValidator.sol

@@ -35,9 +35,9 @@ contract ECDSAValidator is IValidator, IHook, IStatelessValidator, IStatelessVal
 
     function onInstall(bytes calldata _data) external payable override {
         if (_isInitialized(msg.sender)) revert AlreadyInitialized(msg.sender);
-        if (_data.length != 20) revert InvalidDataLength();
+        require(_data.length == 20, InvalidDataLength());
         address owner = address(bytes20(_data[0:20]));
-        if (owner == address(0)) revert ZeroAddressOwner();
+        require(owner != address(0), ZeroAddressOwner());
         ecdsaValidatorStorage[msg.sender].owner = owner;
         emit OwnerRegistered(msg.sender, owner);
     }