237-combo/docs/SECURITY.md

🔐 Security Best Practices

Comprehensive security checklist for DeFi integration.

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🛡️ General Security Principles

🔒 1. Access Control

• ✅ Use access control modifiers for sensitive functions
• ✅ Implement owner/admin roles properly
• ✅ Never hardcode private keys or mnemonics
• ✅ Use environment variables for sensitive data

✅ 2. Input Validation

• ✅ Validate all user inputs
• ✅ Check for zero addresses
• ✅ Validate amounts (no zero, no overflow)
• ✅ Check token decimals

🔄 3. Reentrancy Protection

• ✅ Use ReentrancyGuard for external calls
• ✅ Follow checks-effects-interactions pattern
• ✅ Be extra careful with flash loans

⚠️ 4. Error Handling

• ✅ Use require/assert appropriately
• ✅ Provide clear error messages
• ✅ Handle edge cases
• ✅ Test error conditions

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🏦 Protocol-Specific Security

🏦 Aave v3

⚡ Flash Loans

Check	Status	Description
⚠️ Critical	✅	Always repay flash loan + premium in executeOperation
⚠️ Critical	✅	Verify msg.sender == pool in executeOperation
⚠️ Critical	✅	Verify initiator == address(this) in executeOperation
✅	✅	Calculate premium correctly: amount + premium
✅	✅	Handle multi-asset flash loans carefully
✅	✅	Test repayment failure scenarios

💰 Interest Rate Modes

Check	Status	Description
⚠️ Deprecated	✅	Stable rate borrowing is deprecated in v3.3+
✅	✅	Always use variable rate (mode = 2) for new integrations
✅	✅	Understand interest rate risks

🛡️ Collateral Management

• ✅ Check liquidation thresholds
• ✅ Monitor health factor
• ✅ Handle eMode/isolation mode restrictions
• ✅ Verify collateral can be enabled

🔄 Uniswap v3

🛡️ Slippage Protection

Check	Status	Description
⚠️ Critical	✅	Always set amountOutMinimum with slippage tolerance
✅	✅	Use TWAP oracles, not spot prices
✅	✅	Account for price impact in large swaps
✅	✅	Consider using UniswapX for better execution

🔮 Oracle Security

Check	Status	Description
⚠️ Critical	✅	Never use spot prices for critical operations
✅	✅	Use TWAP with sufficient observation window
✅	✅	Verify observation cardinality
✅	✅	Protect against oracle manipulation

🔐 Permit2

• ✅ Verify signature validity
• ✅ Check expiration (deadline)
• ✅ Verify nonce (prevent replay)
• ✅ Protect against signature theft (verify spender)

🔗 Protocolink

✅ Route Validation

• ✅ Verify all logics in the route
• ✅ Check token addresses
• ✅ Validate amounts
• ✅ Verify slippage settings

⚡ Execution

• ✅ Check gas estimates
• ✅ Handle execution failures
• ✅ Verify router address
• ✅ Monitor transaction status

🏛️ Compound III

💰 Borrowing

Check	Status	Description
⚠️ Important	✅	Understand base asset vs collateral
✅	✅	Check borrow limits
✅	✅	Monitor collateral ratio
✅	✅	Handle liquidation risks

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📜 Smart Contract Security

⚡ Flash Loan Receivers

// ✅ Good: Verify caller and initiator
function executeOperation(
    address asset,
    uint256 amount,
    uint256 premium,
    address initiator,
    bytes calldata params
) external override returns (bool) {
    require(msg.sender == address(pool), "Invalid caller");
    require(initiator == address(this), "Invalid initiator");
    
    // Your logic here
    
    // ✅ Good: Approve repayment
    IERC20(asset).approve(address(pool), amount + premium);
    return true;
}

🔄 Reentrancy Protection

// ✅ Good: Use ReentrancyGuard
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

contract MyContract is ReentrancyGuard {
    function withdraw() external nonReentrant {
        // Safe withdrawal logic
    }
}

🔒 Access Control

// ✅ Good: Use access control
import "@openzeppelin/contracts/access/Ownable.sol";

contract MyContract is Ownable {
    function sensitiveFunction() external onlyOwner {
        // Owner-only logic
    }
}

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🧪 Testing Security

🧪 Foundry Tests

• ✅ Test all edge cases
• ✅ Test error conditions
• ✅ Test reentrancy attacks
• ✅ Test flash loan scenarios
• ✅ Test with fork tests
• ✅ Test gas limits

📊 Test Coverage

• ✅ Unit tests for all functions
• ✅ Integration tests
• ✅ Fork tests on mainnet
• ✅ Fuzz tests for inputs
• ✅ Invariant tests

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🚀 Deployment Security

🔍 Pre-Deployment

• ✅ Get professional security audit
• ✅ Review all dependencies
• ✅ Test on testnets extensively
• ✅ Verify all addresses
• ✅ Check contract sizes

🔐 Post-Deployment

• ✅ Monitor transactions
• ✅ Set up alerts
• ✅ Keep private keys secure
• ✅ Use multisig for admin functions
• ✅ Have an emergency pause mechanism

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⚠️ Common Vulnerabilities

1. Reentrancy

❌ Bad: External call before state update

function withdraw() external {
    msg.sender.call{value: balance}("");
    balance = 0; // Too late!
}

✅ Good: State update before external call

function withdraw() external nonReentrant {
    uint256 amount = balance;
    balance = 0;
    msg.sender.call{value: amount}("");
}

2. Integer Overflow

❌ Bad: No overflow protection

uint256 total = amount1 + amount2;

✅ Good: Use SafeMath or Solidity 0.8+

uint256 total = amount1 + amount2; // Safe in Solidity 0.8+

3. Access Control

❌ Bad: No access control

function withdraw() external {
    // Anyone can call
}

✅ Good: Proper access control

function withdraw() external onlyOwner {
    // Only owner can call
}

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🔗 Resources

Resource	Link
OpenZeppelin Security	docs.openzeppelin.com
Consensys Best Practices	consensys.github.io
Aave Security	docs.aave.com
Uniswap Security	docs.uniswap.org

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✅ Security Audit Checklist

Before deploying to production:

• 🔍 Professional security audit completed
• 📦 All dependencies reviewed
• 🔒 Access control implemented
• 🔄 Reentrancy protection added
• ✅ Input validation implemented
• ⚠️ Error handling comprehensive
• 🧪 Tests cover edge cases
• ⛽ Gas optimization reviewed
• ⏸️ Emergency pause mechanism
• 👥 Multisig for admin functions
• 📊 Monitoring and alerts set up

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🚨 Reporting Security Issues

If you discover a security vulnerability, please report it responsibly:

1. ⛔ DO NOT open a public issue
2. 📧 Email security details to the maintainers
3. ⏰ Allow time for the issue to be addressed
4. 🔒 Follow responsible disclosure practices

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⚠️ Disclaimer

This security guide is for educational purposes. Always get professional security audits before deploying to production.

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📚 Related Documentation

• 📖 Integration Guide
• 🔗 Chain Configuration
• 🧪 Strategy Testing Guide