~~NOTOC~~
====== Szenario 10.1: TLS-Server einrichten ======

<WRAP round info>
**Kategorie:** [[.:start|TLS/mTLS]] \\
**Komplexität:** ⭐⭐⭐ (Mittel) \\
**Voraussetzungen:** Server-Zertifikat, Private Key \\
**Geschätzte Zeit:** 20-30 Minuten
</WRAP>

----

===== Beschreibung =====

Dieses Szenario beschreibt die **Einrichtung eines TLS-Servers** mit Post-Quantum-sicheren Zertifikaten. TLS 1.3 ist Pflicht für moderne Sicherheit.

**Komponenten:**
  * Server-Zertifikat (ML-DSA oder Hybrid)
  * Zertifikatskette (Intermediate + Root)
  * TLS-Konfiguration
  * Cipher Suites

----

===== Workflow =====

<mermaid>
flowchart LR
    CERT[Zertifikat vorbereiten] --> CHAIN[Kette erstellen]
    CHAIN --> CONFIG[TLS konfigurieren]
    CONFIG --> TEST[Testen]
    TEST --> DEPLOY[Deployment]

    style CONFIG fill:#e8f5e9
</mermaid>

----

===== Code-Beispiel: ASP.NET Core Kestrel =====

<code csharp>
using Microsoft.AspNetCore.Server.Kestrel.Core;
using Microsoft.AspNetCore.Server.Kestrel.Https;

var builder = WebApplication.CreateBuilder(args);

builder.WebHost.ConfigureKestrel(options =>
{
    options.ListenAnyIP(443, listenOptions =>
    {
        listenOptions.UseHttps(httpsOptions =>
        {
            // Server-Zertifikat laden
            httpsOptions.ServerCertificate = LoadCertificateChain(
                "server.crt.pem",
                "server.key.pem",
                "intermediate-ca.crt.pem"
            );

            // TLS 1.3 erzwingen
            httpsOptions.SslProtocols = SslProtocols.Tls13;

            // OCSP Stapling aktivieren
            httpsOptions.OnAuthenticate = (context, sslOptions) =>
            {
                sslOptions.CertificateRevocationCheckMode = X509RevocationMode.Online;
            };
        });

        // HTTP/2 aktivieren
        listenOptions.Protocols = HttpProtocols.Http1AndHttp2;
    });
});

var app = builder.Build();

// HSTS aktivieren
app.UseHsts();

app.MapGet("/", () => "TLS Server aktiv");

app.Run();

static X509Certificate2 LoadCertificateChain(
    string certPath,
    string keyPath,
    string chainPath)
{
    using var ctx = PqCryptoContext.Initialize();

    // Server-Zertifikat mit Private Key
    var cert = ctx.LoadCertificateWithPrivateKey(certPath, keyPath, null);

    // Chain hinzufügen (für vollständige Kette)
    var intermediate = ctx.LoadCertificate(chainPath);

    // PFX mit Chain erstellen
    var pfxBytes = ctx.ExportToPfx(cert, cert.GetRSAPrivateKey(), new[] { intermediate }, null);
    return new X509Certificate2(pfxBytes);
}
</code>

----

===== Nginx Konfiguration =====

<code nginx>
server {
    listen 443 ssl http2;
    server_name www.example.com;

    # Server-Zertifikat (mit Chain)
    ssl_certificate     /etc/nginx/ssl/server-chain.pem;
    ssl_certificate_key /etc/nginx/ssl/server.key.pem;

    # TLS 1.3 only
    ssl_protocols TLSv1.3;

    # Cipher Suites (TLS 1.3 default)
    # ssl_ciphers TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256;
    ssl_prefer_server_ciphers off;

    # OCSP Stapling
    ssl_stapling on;
    ssl_stapling_verify on;
    ssl_trusted_certificate /etc/nginx/ssl/ca-chain.pem;
    resolver 8.8.8.8 8.8.4.4 valid=300s;
    resolver_timeout 5s;

    # Security Headers
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains; preload" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-Frame-Options "DENY" always;

    # Session-Konfiguration
    ssl_session_timeout 1d;
    ssl_session_cache shared:SSL:50m;
    ssl_session_tickets off;

    location / {
        proxy_pass http://backend:8080;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}
</code>

----

===== Apache Konfiguration =====

<code apache>
<VirtualHost *:443>
    ServerName www.example.com

    # SSL aktivieren
    SSLEngine on

    # Zertifikate
    SSLCertificateFile      /etc/apache2/ssl/server.crt.pem
    SSLCertificateKeyFile   /etc/apache2/ssl/server.key.pem
    SSLCertificateChainFile /etc/apache2/ssl/intermediate-ca.crt.pem

    # TLS 1.3 only
    SSLProtocol -all +TLSv1.3

    # OCSP Stapling
    SSLUseStapling On
    SSLStaplingCache "shmcb:logs/ssl_stapling(32768)"
    SSLStaplingResponderTimeout 5
    SSLStaplingReturnResponderErrors off

    # HSTS
    Header always set Strict-Transport-Security "max-age=63072000; includeSubDomains; preload"

    # Compression deaktivieren (BREACH)
    SSLCompression off

    <Directory /var/www/html>
        Options -Indexes +FollowSymLinks
        AllowOverride All
        Require all granted
    </Directory>
</VirtualHost>
</code>

----

===== Zertifikatskette erstellen =====

<code bash>
# Server-Zertifikat + Intermediate = Chain
cat server.crt.pem intermediate-ca.crt.pem > server-chain.pem

# Reihenfolge prüfen
openssl crl2pkcs7 -nocrl -certfile server-chain.pem | openssl pkcs7 -print_certs -noout

# Chain validieren
openssl verify -CAfile root-ca.crt.pem -untrusted intermediate-ca.crt.pem server.crt.pem
</code>

----

===== TLS-Konfiguration testen =====

<code bash>
# SSL Labs API (wenn öffentlich)
# https://www.ssllabs.com/ssltest/

# Lokaler Test mit OpenSSL
openssl s_client -connect localhost:443 -tls1_3 -brief

# Cipher Suites prüfen
openssl s_client -connect localhost:443 -cipher 'TLS_AES_256_GCM_SHA384' </dev/null

# Zertifikatskette prüfen
openssl s_client -connect localhost:443 -showcerts </dev/null 2>/dev/null | openssl x509 -text -noout

# OCSP Stapling prüfen
openssl s_client -connect localhost:443 -status </dev/null 2>/dev/null | grep -A 5 "OCSP Response"

# testssl.sh (umfassend)
./testssl.sh localhost:443
</code>

----

===== C# Test-Client =====

<code csharp>
public async Task TestTlsConnection(string url)
{
    var handler = new HttpClientHandler
    {
        ServerCertificateCustomValidationCallback = (message, cert, chain, errors) =>
        {
            Console.WriteLine($"Server: {cert.Subject}");
            Console.WriteLine($"Issuer: {cert.Issuer}");
            Console.WriteLine($"Algorithm: {cert.SignatureAlgorithm.FriendlyName}");
            Console.WriteLine($"Valid until: {cert.NotAfter}");

            if (chain != null)
            {
                Console.WriteLine($"Chain length: {chain.ChainElements.Count}");
                foreach (var element in chain.ChainElements)
                {
                    Console.WriteLine($"  - {element.Certificate.Subject}");
                }
            }

            if (errors != SslPolicyErrors.None)
            {
                Console.WriteLine($"SSL Errors: {errors}");
                return false;
            }

            return true;
        }
    };

    using var client = new HttpClient(handler);
    var response = await client.GetAsync(url);

    Console.WriteLine($"Status: {response.StatusCode}");
    Console.WriteLine($"Protocol: {response.Version}");
}
</code>

----

===== Branchenspezifische TLS-Anforderungen =====

^  Branche  ^  Min. TLS  ^  Cipher Suites  ^  Besonderheit  ^
| **PCI-DSS** | TLS 1.2+ | Starke Ciphers | Jährliche Prüfung |
| **HIPAA** | TLS 1.2+ | AES-256 | Audit-Logging |
| **BSI TR-02102** | TLS 1.2+ | BSI-konforme Suites | PFS Pflicht |
| **Energie/SCADA** | TLS 1.2+ | ICS-spezifisch | Langzeit-Support |

----

===== Verwandte Szenarien =====

^  Beziehung  ^  Szenario  ^  Beschreibung  ^
| **Voraussetzung** | [[de:int:pqcrypt:szenarien:zertifikate:server_cert|3.1 Server-Zertifikat]] | Cert erstellen |
| **Nächster Schritt** | [[.:client_config|10.2 TLS-Client]] | Client konfigurieren |
| **Erweiterung** | [[.:mtls_deployment|10.3 mTLS Deployment]] | Gegenseitige Auth |

----

<< [[.:start|← TLS-Übersicht]] | [[de:int:pqcrypt:szenarien:start|↑ Szenarien]] | [[.:client_config|10.2 TLS-Client →]] >>

{{tag>szenario tls server nginx kestrel https}}

----
//Wolfgang van der Stille @ EMSR DATA d.o.o. - Post-Quantum Cryptography Professional//