fix(contracts): Require contract addresses to be non-zero

beacon-light-client/plonky2/input_fetchers/balance_verification/abi/validators_accumulator_abi.json

@@ -10,6 +10,11 @@
     "stateMutability": "nonpayable",
     "type": "constructor"
   },
+  {
+    "inputs": [],
+    "name": "ZeroAddressError",
+    "type": "error"
+  },
   {
     "anonymous": false,
     "inputs": [

beacon-light-client/solidity/contracts/Errors.sol

@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: Apache-2.0
+pragma solidity ^0.8.19;
+
+/// @dev Proxy contract address is zero
+error ZeroAddressError();

beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifier.sol

@@ -3,6 +3,7 @@ pragma solidity ^0.8.20;
 
 import {PlonkVerifier} from './verifier.sol';
 import {IBalanceVerifier} from './interfaces/IBalanceVerifierDiva.sol';
+import {ZeroAddressError} from '../Errors.sol';
 import '@openzeppelin/contracts/access/Ownable.sol';
 
 abstract contract BalanceVerifier is Ownable, IBalanceVerifier {
@@ -28,12 +29,19 @@ abstract contract BalanceVerifier is Ownable, IBalanceVerifier {
     address _verifier,
     address _owner
   ) Ownable(_owner) {
+    if (_verifier == address(0)) {
+      revert ZeroAddressError();
+    }
+    verifier = _verifier;
+
     VERIFIER_DIGEST = verifierDigest;
     GENESIS_BLOCK_TIMESTAMP = genesisBlockTimestamp;
-    verifier = _verifier;
   }
 
   function setVerifier(address _verifier) external override onlyOwner {
+    if (_verifier == address(0)) {
+      revert ZeroAddressError();
+    }
     verifier = _verifier;
   }
 

beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifierDiva.sol

@@ -4,6 +4,7 @@ pragma solidity ^0.8.19;
 import {BalanceVerifier} from './BalanceVerifier.sol';
 import {IBalanceVerifierDiva} from './interfaces/IBalanceVerifierDiva.sol';
 import {IValidatorsAccumulator} from '../validators_accumulator/interfaces/IValidatorsAccumulator.sol';
+import {ZeroAddressError} from '../Errors.sol';
 
 contract BalanceVerifierDiva is BalanceVerifier, IBalanceVerifierDiva {
   /// @notice The address of the validators accumulator contract.
@@ -18,6 +19,9 @@ contract BalanceVerifierDiva is BalanceVerifier, IBalanceVerifierDiva {
     address _accumulator,
     address _owner
   ) BalanceVerifier(verifierDigest, genesisBlockTimestamp, _verifier, _owner) {
+    if (_accumulator == address(0)) {
+      revert ZeroAddressError();
+    }
     ACCUMULATOR = _accumulator;
   }
 
@@ -80,6 +84,9 @@ contract BalanceVerifierDiva is BalanceVerifier, IBalanceVerifierDiva {
   }
 
   function setAccumulator(address _accumulator) external override onlyOwner {
+    if (_accumulator == address(0)) {
+      revert ZeroAddressError();
+    }
     ACCUMULATOR = _accumulator;
   }
 

beacon-light-client/solidity/contracts/validators_accumulator/ValidatorsAccumulator.sol

@@ -3,6 +3,7 @@ pragma solidity ^0.8.18;
 
 import {IDeposit} from './interfaces/IDeposit.sol';
 import {IValidatorsAccumulator} from './interfaces/IValidatorsAccumulator.sol';
+import {ZeroAddressError} from '../Errors.sol';
 
 contract ValidatorsAccumulator is IValidatorsAccumulator {
   // The depth of the validator accumulator tree
@@ -21,6 +22,9 @@ contract ValidatorsAccumulator is IValidatorsAccumulator {
   uint256[] internal blockNumbers;
 
   constructor(address _depositAddress) {
+    if (_depositAddress == address(0)) {
+      revert ZeroAddressError();
+    }
     depositAddress = _depositAddress;
 
     // Compute hashes in empty Merkle tree