====== HAProxy Config Files ======
===== HAProxy =====
<code># /etc/haproxy/haproxy.cfg
# 0. Settings
global
    log /dev/log local0
    log /dev/log local1 notice
    chroot /var/lib/haproxy
    user haproxy
    group haproxy
    daemon

    # Modern SSL/TLS security settings for Debian 13
    # Minimum TLS version requirement
    ssl-default-bind-options ssl-min-ver TLSv1.2 no-tls-tickets

    # TLS 1.3 Cipher Suites (handled by ssl-default-bind-ciphersuites)
    ssl-default-bind-ciphersuites TLS_AES_128_GCM_SHA256:TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256

    # TLS 1.2 Ciphers (handled by ssl-default-bind-ciphers)
    ssl-default-bind-ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384

    # Administrative socket for stats/management
    stats socket /run/haproxy/admin.sock mode 660 level admin expose-fd listeners
    stats timeout 30s

defaults
    log     global
    mode    tcp
    log-format "%ci:%cp [%t] %ft %b/%s %Tw/%Tc/%Tt %B %ts %ac/%fc/%bc/%sc/%rc %sq/%bq"
    timeout connect 5s
    timeout client  50s
    timeout server  50s

# 1. Public Interface (SNI Router)
frontend public_inbound_http
    bind *:80
    mode http

    # Deny traffic based on origin
    http-request deny if { src -f /etc/haproxy/blacklist.lst }

    # Redirect all incoming traffic to HTTPS permanently
    http-request redirect scheme https code 301 unless { ssl_fc }

frontend public_inbound
    bind :443
    mode tcp
    
    # Deny traffic based on origin
    tcp-request connection reject if { src -f /etc/haproxy/blacklist.lst }

    # Wait for the TLS client hello to parse the SNI extension
    tcp-request inspect-delay 5s
    tcp-request content accept if { req.ssl_hello_type 1 }

    # Define the domains (one line for each) you want to terminate SSL for
    acl terminate_ssl req.ssl_sni -i bak.condrau.com

    # Route conditionally based on SNI
    use_backend http_dispatcher if terminate_ssl
    default_backend passthrough_server

# 2. Transparent passthrough for encrypted TLS domains
backend passthrough_server
    mode tcp

    # downstream server handling its own TLS certificates (Calypso)
    server calypso 192.168.3.18:443 check

# 3. Intermediary loopback backend
# This forwards traffic to the Layer 7 (HTTP) processing frontend
backend http_dispatcher
    mode tcp
    server loopback 127.0.0.1:8443 send-proxy-v2

# 4. Layer 7 http frontend
# Receives traffic from the loopback, decrypts SSL, and processes HTTP rules
frontend internal_inbound_http

    # pass certs directory path so all pem files will be loaded
    bind 127.0.0.1:8443 ssl crt /etc/haproxy/certs/ accept-proxy
    mode http

    # Deny traffic based on origin (host aware)
    acl trusted_ip src -f /etc/haproxy/whitelist.lst 
    acl backuppc hdr(host) -i bak.condrau.com
    http-request deny if backuppc !trusted_ip

    # Inject headers so backend servers know the original request was HTTPS
    http-request set-header X-Forwarded-Proto https
    http-request set-header X-Forwarded-Port 443
    http-request set-header X-Forwarded-For %[src]

    # Route traffic based on HTTP host headers
    use_backend backuppc_server if backuppc
    # default_backend backuppc_server

# 5. HTTP backends
backend backuppc_server
    mode http
    cookie SERVERID insert indirect nocache
    server epione 192.168.1.14:8080 check
</code>

===== Whitelist =====
<code># /etc/haproxy/whitelist.lst
# Allow static addresses
183.88.218.149
109.205.169.18
# Allow dynamic addresses 'dig +short host.mydyndns.org'
183.88.218.149
</code>

===== Blacklist =====
<code># /etc/haproxy/blacklist.lst
# Deny malicious IP addresses
148.66.10.94
5.188.62.0/24
54.39.29.64
185.185.134.115
185.46.46.0/24
</code>

===== Powershell =====
<code># D:\update-dns.ps1
# This is an example Powershell file for DuckDNS updater, see https://www.duckdns.org
param($domain)
$duckdomain = if (!$domain) { "my-default-domain-name" } else { $domain }
$addr = curl.exe -s "https://api.ipify.org"
curl.exe -k "https://www.duckdns.org/update?domains=$duckdomain&token=xxxxxxxx-yyyy-zzzz-*my*-*duckdnstoken*&ip=$addr"
</code>
Use it with ''C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -ExecutionPolicy Bypass -File "D:\update-dns.ps1"''