Security Implementation

Overview

The SUDIGITAL API implements comprehensive security measures to protect user data, trading operations, and administrative functions. This document outlines the multi-layered security approach implemented in Step 5.6.

Security Features

1. API Key Encryption

Implementation: packages/api/src/services/encryption.service.ts

• Algorithm: AES-256-CBC with scrypt key derivation
• Key Management: Environment-based encryption key
• Storage: Encrypted format in database with validation
• Security: Secure encryption/decryption with proper error handling

// Example usage
const encrypted = encryptionService.encrypt(apiKey)
const decrypted = encryptionService.decrypt(encrypted)

2. Rate Limiting

Implementation: packages/api/src/middleware/rate-limit.middleware.ts

Rate Limit Tiers

Endpoint Type	Limit	Window	Purpose
Trading Operations	100 requests	15 minutes	Normal trading activity
Exchange Keys	10 requests	1 hour	High security for credentials
General API	200 requests	15 minutes	Standard API operations
Admin Operations	50 requests	1 hour	Strict limits for management

Features

• User & IP-based tracking: Prevents both user and network abuse
• Automatic cleanup: Expired records removed every 5 minutes
• Graceful errors: Returns retry-after headers for client handling
• Memory efficient: In-memory storage with periodic cleanup

3. Role-based Access Control

Implementation: packages/api/src/middleware/trading-auth.middleware.ts

Permission Matrix

Role	Trading	API Keys	Bots	View All	Exchanges	Assets	Markets
Super Admin	✅	✅	✅	✅	✅	✅	✅
Admin	✅	✅	✅	✅	✅	✅	✅
Moderator	✅	✅	✅	❌	❌	❌	❌
Owner	✅	✅	✅	❌	❌	❌	❌
Worker	✅	✅	✅	❌	❌	❌	❌
Player	✅	✅	❌	❌	❌	❌	❌
User	✅	✅	❌	❌	❌	❌	❌

Permission Functions

// Available middleware functions
requireTradingPermission // Can trade
requireApiKeyPermission // Can manage API keys
requireBotPermission // Can create bots
requireExchangeManagement // Can manage exchanges (admin only)
requireAssetManagement // Can manage assets (admin only)
requireMarketManagement // Can manage markets (admin only)
requireOwnership() // Resource ownership validation

4. Enhanced Authentication

Implementation: Integrated across all trading routes

Features

• JWT Validation: Secure token verification with expiration checks
• Real-time Status: Active user validation on each request
• Role Authorization: Permission-based access control
• Ownership Verification: Users can only access their own resources
• Admin Override: Admins can access all resources for management

Route Security Integration

Exchange Keys

// Security stack for exchange key management
app.use('*', exchangeKeyRateLimit) // 10 requests/hour
app.use('*', tradingAuth) // JWT + role validation
app.use('*', requireApiKeyPermission) // API key permission
app.use('/users/:userId/*', requireOwnership()) // User ownership

Trading Bots

// Security stack for bot management
app.use('*', tradingRateLimit) // 100 requests/15min
app.use('*', tradingAuth) // JWT + role validation
app.use('*', requireBotPermission) // Bot creation permission
app.use('/users/:userId/*', requireOwnership()) // User ownership

Transactions

// Security stack for transaction history
app.use('*', tradingRateLimit) // 100 requests/15min
app.use('*', tradingAuth) // JWT + role validation
app.use('/users/:userId/*', requireOwnership()) // User ownership
app.use('/bots/:botId/*', requireOwnership()) // Bot ownership

Admin Routes (Assets, Exchanges, Markets)

// Security stack for admin operations
app.use('*', generalApiRateLimit) // 200 requests/15min
app.use('*', tradingAuth) // JWT + role validation
// Method-specific admin permissions applied conditionally

Security Best Practices

Environment Configuration

# Required environment variables
JWT_SECRET=your-secure-jwt-secret
ENCRYPTION_KEY=your-32-byte-encryption-key
ENCRYPTION_SALT=your-16-byte-salt

Error Handling

• No sensitive data exposure: Error messages don't leak internal details
• Consistent responses: Standardized error format across all endpoints
• Rate limit feedback: Clear retry-after information for clients
• Audit trails: Security events logged for monitoring

Database Security

• Encrypted credentials: All API keys encrypted before storage
• Access patterns: Role-based data access restrictions
• Ownership validation: Users can only access their own data
• Admin oversight: Controlled admin access with full audit trails

Usage Examples

Accessing Protected Endpoints

// Client must include JWT token
const headers = {
  Authorization: `Bearer ${userToken}`,
  'Content-Type': 'application/json',
}

// Rate limits apply automatically
const response = await fetch('/api/users/123/bots', { headers })

Error Responses

{
  "success": false,
  "error": "Too many requests, please try again later",
  "retryAfter": 3600
}

{
  "success": false,
  "error": "Permission denied"
}

Monitoring and Compliance

Security Metrics

• Rate limit violations tracked per user/IP
• Permission denials logged with context
• Authentication failures monitored
• Encryption/decryption operations audited

Compliance Features

• Data protection: All sensitive data encrypted at rest
• Access control: Granular permission system
• Audit trails: Comprehensive security event logging
• Rate limiting: Prevents abuse and ensures fair usage

Next Steps

The security implementation provides a robust foundation for:

1. Production deployment: Ready for production trading operations
2. Compliance audits: Comprehensive security controls in place
3. Monitoring integration: Built-in security metrics and logging
4. Future enhancements: Extensible permission and rate limiting system