From 174763a678029622450739c712e58e6a1881e977 Mon Sep 17 00:00:00 2001
From: Martin Ivanov <xeartybg@gmail.com>
Date: Tue, 18 Jun 2024 14:34:36 +0300
Subject: [PATCH] fix(contracts): Require contract addresses to be non-zero

---
 .../abi/validators_accumulator_abi.json                |  5 +++++
 beacon-light-client/solidity/contracts/Errors.sol      |  5 +++++
 .../contracts/balance_verifier/BalanceVerifier.sol     | 10 +++++++++-
 .../contracts/balance_verifier/BalanceVerifierDiva.sol |  7 +++++++
 .../validators_accumulator/ValidatorsAccumulator.sol   |  4 ++++
 5 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 beacon-light-client/solidity/contracts/Errors.sol

diff --git a/beacon-light-client/plonky2/input_fetchers/balance_verification/abi/validators_accumulator_abi.json b/beacon-light-client/plonky2/input_fetchers/balance_verification/abi/validators_accumulator_abi.json
index 1950af76c..e0f43cbbc 100644
--- a/beacon-light-client/plonky2/input_fetchers/balance_verification/abi/validators_accumulator_abi.json
+++ b/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": [
diff --git a/beacon-light-client/solidity/contracts/Errors.sol b/beacon-light-client/solidity/contracts/Errors.sol
new file mode 100644
index 000000000..9db1f9325
--- /dev/null
+++ b/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();
diff --git a/beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifier.sol b/beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifier.sol
index ecc8b9bd0..bd3bfc8be 100644
--- a/beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifier.sol
+++ b/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;
   }
 
diff --git a/beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifierDiva.sol b/beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifierDiva.sol
index 73e8a9b4f..6412e8446 100644
--- a/beacon-light-client/solidity/contracts/balance_verifier/BalanceVerifierDiva.sol
+++ b/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;
   }
 
diff --git a/beacon-light-client/solidity/contracts/validators_accumulator/ValidatorsAccumulator.sol b/beacon-light-client/solidity/contracts/validators_accumulator/ValidatorsAccumulator.sol
index 19d254818..1b591d7f6 100644
--- a/beacon-light-client/solidity/contracts/validators_accumulator/ValidatorsAccumulator.sol
+++ b/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