Extending jHTTPd: Writing Custom Handlers and Middleware

Securing jHTTPd: Best Practices for Authentication and HTTPS

jHTTPd is a lightweight Java HTTP server used for embedded or minimal web services. This guide gives practical, prescriptive steps to harden jHTTPd deployments with authentication and HTTPS, plus configuration examples and quick checks.

1) Use HTTPS everywhere

• Generate a keystore (RSA 2048+ or ECDSA P-256+) and protect it with a strong password.
  • Example (keytool):

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    keytool -genkeypair -alias jhttpd -keyalg RSA -keysize 2048 -keystore jhttpd.jks -validity 8250 

• Enable TLS in jHTTPd (assume jHTTPd exposes a makeSSLSocketFactory / makeSecure API similar to small Java servers):
  • Load keystore and create SSLContext, then pass to server.makeSecure(…).
• Prefer modern TLS: disable SSLv3/TLS 1.0/1.1; allow TLS 1.2+ and 1.3 only.
• Use secure cipher suites: prefer AEAD ciphers (AES-GCM, CHACHA20-POLY1305).
• Certificate management: use CA-signed certs (Let’s Encrypt for public services) and automate renewal. For internal services, use short-lived certs with an internal PKI.

2) Protect private keys and keystore

• Store keystore on a secure filesystem with restricted permissions (owner only).
• Rotate keystore/passwords on a regular schedule or if suspected compromise.
• Do not store keystore password in plaintext in source control; use environment variables or a secret store (Vault, OS keyring).

3) Enforce authentication and authorization

• Choose an auth model appropriate for your environment:
  • For internal tools: HTTP Basic over TLS + server-side credential store (hashed+salted).
  • For public/modern apps: token-based (JWT/OAuth2) or session-based auth behind TLS.
• Avoid Basic over plain HTTP. If you must use HTTP Basic, require HTTPS and short-lived tokens.
• Store passwords safely: bcrypt/argon2 with per-user salt; never store plaintext.
• Implement least privilege: map authenticated identities to minimal required permissions.
• Session handling:
  • Use secure, HttpOnly cookies with SameSite=strict/lax when using cookie sessions.
  • Invalidate sessions on logout and rotate session identifiers after privilege changes.
• Example: Basic auth handler (conceptual Java snippet):

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  // Pseudocode: authenticate header, compare bcrypt hash, set principal String auth = request.getHeader(“Authorization”); if (auth != null && auth.startsWith(“Basic “)) {String[] parts = decodeBasic(auth).split(”:“,2);
  
   
  if (verifyPassword(parts[0], parts[1])) {     request.setUserPrincipal(new Principal(parts[0])); } else {     respondUnauthorized(); } 
  } else respondUnauthorized(); 
  
  

4) Use strong defaults and header hardening

• Add security headers:
  • Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
  • Content-Security-Policy: limit allowed sources
  • X-Content-Type-Options: nosniff
  • X-Frame-Options: DENY (or use CSP frame-ancestors)
  • Referrer-Policy: no-referrer-when-downgrade (or stricter)
• Disable directory listings and verbose error pages that leak stack traces or internal paths.
• Limit request methods to only those needed (e.g., GET, POST).

5) Rate limiting, brute-force protection, and logging

• Implement request rate limits per IP and per account to mitigate brute-force and DoS attempts.
• Add exponential backoff or temporary lockouts for repeated failed logins.
• Log authentication events (success/failure, source IP, username) to a secure, centralized log (avoid logging passwords).
• Monitor logs and set alerts for suspicious activity.

6) Input validation and safe handler code

• Validate and canonicalize all paths to avoid path traversal when serving files.
• Limit upload sizes and write uploaded files to secure temporary directories with safe permissions.
• Run jHTTPd with least-privileged OS user; isolate via containers or a dedicated JVM with limited file access.

7) Use reverse proxy / edge protections for production

• Put a hardened reverse proxy (Nginx, Envoy, Apache) in front of jHTTPd when exposing to the Internet:
  • Terminate TLS at the proxy (or use mutual TLS) and forward only internal traffic to jHTTPd.
  • Offload WAF rules, rate limiting, caching, and health checks to the proxy.
  • Proxy can centralize authentication (e.g., OAuth2 proxy) so jHTTPd can remain simple.

8) Testing and verification

• Run TLS configuration scanners (SSL Labs, testssl.sh) and aim for modern scores.
• Pen-test authentication flows and do credential stuffing tests (in controlled environment).
• Regularly run static analysis and dependency vulnerability scans against your code and libraries.

9) Deployment and maintenance checklist

• TLS only (redirect HTTP -> HTTPS)
• Keystore protected and rotated
• Strong ciphers and TLS versions enforced
• Authentication enabled and password hashing used
• Rate limiting and brute-force protections
• Security headers configured
• Logging and monitoring in place
• Reverse proxy/WAF in front for Internet-facing servers
• Regular vulnerability scanning and patching schedule

10) Quick sample minimal config (conceptual)

• Start server on HTTPS only, enforce auth for sensitive paths, serve static files from safe root, log to syslog. (Implement per your jHTTPd API; adapt keystore and handler code snippets above.)

Conclusion

• Use TLS everywhere, protect keys, enforce strong authentication and session practices, harden handlers and headers, rate-limit and monitor. For Internet-facing services, combine jHTTPd with a reverse proxy for better security and operational controls.