Debugging SSL Handshakes in Code

1 min read SSL/TLS & Certificates

Debugging SSL Handshakes in Code

Programmatic SSL debugging requires visibility into handshake processes. Enable verbose logging and capture handshake details for troubleshooting.

Java SSL debugging:

// Enable SSL debugging
System.setProperty("javax.net.debug", "ssl:handshake");

// Custom trust manager for debugging
TrustManager[] trustAllCerts = new TrustManager[] {
    new X509TrustManager() {
        public X509Certificate[] getAcceptedIssuers() { return null; }
        public void checkClientTrusted(X509Certificate[] certs, String authType) { }
        public void checkServerTrusted(X509Certificate[] certs, String authType) {
            System.out.println("Server certificates:");
            for (X509Certificate cert : certs) {
                System.out.println("  Subject: " + cert.getSubjectDN());
                System.out.println("  Issuer: " + cert.getIssuerDN());
                System.out.println("  Valid from: " + cert.getNotBefore());
                System.out.println("  Valid until: " + cert.getNotAfter());
            }
        }
    }
};

SSLContext sc = SSLContext.getInstance("TLS");
sc.init(null, trustAllCerts, new java.security.SecureRandom());
HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());