Banking Software Authentication Strategy

🏦 Critical Security Guidelines for RISWIS Banking System

Middleware Selection Matrix

Operation Type	Middleware	Database Check	Use Case	Security Level
Critical Banking Operations	isAuthenticated	✅ Real-time	User management, transactions, account operations	MAXIMUM
High-Frequency API Calls	verifyToken	❌ Token only	System health, notifications, dashboard stats	STANDARD
Public/Optional Access	optionalAuthenticate	✅ If token present	Public endpoints, optional features	MINIMAL

🚨 CRITICAL: When to Use isAuthenticated

ALWAYS use isAuthenticated for:

• User management operations (/users/*)

• Financial transactions (/transactions/*)

• Account operations (/accounts/*)

• Money transfers (/money-transfer/*)

• Loan operations (/loans/*)

• Audit operations (/audit/*)

• System settings (/system-settings/*)

• Branch management (/branches/*)

Why: These operations require real-time user status validation to prevent:

• Deactivated users from accessing banking functions

• Deleted accounts from performing transactions

• Compromised accounts from unauthorized access

⚡ Performance: When to Use verifyToken

Use verifyToken for:

• Dashboard statistics (/dashboard/stats)

• System health checks (/health)

• Non-critical notifications (/notifications)

• Branding/UI settings (/branding)

• SMS analytics (/sms-analytics)

Why: These operations prioritize performance over real-time user validation.

🔧 Implementation Examples

✅ CORRECT - Critical Banking Route

// backend/src/routes/user.routes.ts
import { isAuthenticated, adminAndManagerOnly } from '../middleware/auth.middleware'

router.use(isAuthenticated as RequestHandler) // Database validation
router.get('/', adminAndManagerOnly, userController.getAllUsers)

❌ INCORRECT - Security Risk

// DON'T DO THIS for banking operations
import { verifyToken } from '../middleware/auth.middleware'

router.use(verifyToken as RequestHandler) // No database validation!
router.get('/users', userController.getAllUsers) // SECURITY RISK!

🔄 Token Refresh Strategy

Frontend Retry Logic

const makeApiCall = async (retryCount = 0): Promise<ApiResponse<T>> => {
  const response = await apiClient.get(endpoint, options);

  // Handle token refresh response
  if (!response.success && 
      response.message === 'Token refreshed, please retry request' && 
      retryCount < 2) {
    console.log('Token was refreshed, retrying request...');
    await new Promise(resolve => setTimeout(resolve, 500));
    return makeApiCall(retryCount + 1);
  }

  return response;
};

Backend Token Validation

// isAuthenticated middleware flow:
// 1. Extract token from header/cookie
// 2. Verify JWT signature and expiration
// 3. Query database for user existence
// 4. Validate user.isActive status
// 5. Attach complete user object to request

📊 Performance vs Security Trade-offs

Aspect	isAuthenticated	verifyToken
Database Queries	1 per request	0 per request
Response Time	~50-100ms slower	Faster
Security Level	Maximum	Standard
Real-time Validation	✅ Current status	❌ Token-time status
Banking Compliance	✅ Recommended	⚠️ Limited use

🛡️ Security Best Practices

1. Route Protection Hierarchy

// Level 1: Critical Banking Operations
router.use(isAuthenticated)
router.use(adminAndManagerOnly)

// Level 2: Standard Operations  
router.use(verifyToken)
router.use(authorize([Role.TELLER, Role.MANAGER]))

// Level 3: Optional Access
router.use(optionalAuthenticate)

2. Error Handling

// Proper error responses for banking
if (!user.isActive) {
  return res.status(403).json({
    success: false,
    message: 'Your account has been deactivated',
    code: 'ACCOUNT_DEACTIVATED'
  });
}

3. Audit Logging

// Log all authentication events
logger.info(`User authenticated: ${user.id}, Role: ${user.role}, Path: ${req.path}`);

🔍 Monitoring & Alerts

Critical Metrics to Track:

• Failed authentication attempts

• Token refresh frequency

• Database query performance for isAuthenticated

• Inactive user access attempts

Alert Thresholds:

• HIGH: >10 failed auth attempts per minute

• CRITICAL: Inactive user attempting banking operations

• WARNING: Token refresh rate >50% of requests

🚀 Performance Optimization

For High-Traffic Endpoints:

1. Cache user status for non-critical operations

2. Use Redis for session management

3. Implement rate limiting on token refresh

4. Monitor database connection pool for auth queries

Database Optimization:

-- Ensure proper indexing for auth queries
CREATE INDEX idx_user_id_active ON users(id, isActive);
CREATE INDEX idx_user_email_active ON users(email, isActive);

📋 Migration Checklist

• Audit all routes using verifyToken

• Identify critical banking operations

• Replace verifyToken with isAuthenticated for critical routes

• Test token refresh retry logic

• Monitor performance impact

• Update API documentation

• Train development team on middleware selection

🎯 Immediate Actions Required

1. Fix token refresh loop in frontend (✅ COMPLETED)

2. Replace verifyToken with isAuthenticated for /users route (✅ COMPLETED)

3. Audit all other critical routes for proper middleware usage

4. Implement comprehensive error handling for token refresh scenarios

5. Add monitoring for authentication failures and performance

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Remember: In banking software, security always takes precedence over performance. When in doubt, use isAuthenticated for real-time user validation.