feat: global proxy protocol support

docs/README.md

@@ -805,6 +805,25 @@ For legacy compatibility reasons, `nginx-proxy` forwards any client-supplied `X-
 
 The default for `TRUST_DOWNSTREAM_PROXY` may change to `false` in a future version of `nginx-proxy`. If you require it to be enabled, you are encouraged to explicitly set it to `true` to avoid compatibility problems when upgrading.
 
+### Proxy Protocol Support
+
+`nginx-proxy` has support for the [Proxy Protocol](https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt). This allows a separate proxy to send requests to `nginx-proxy` and encode information about the client connection without relying on HTTP headers. This can be enabled by setting `ENABLE_PROXY_PROTOCOL=true` on the main `nginx-proxy` container. It's important to note that enabling the proxy protocol will require all connections to `nginx-proxy` to use the protocol.
+
+You can use this feature in conjunction with the `realip` module in nginx. This will allow for setting the `$remote_addr` and `$remote_port` nginx variables to the IP and port that are provided from the protocol message. Documenation for this functionality can be found in the [nginx documentation](https://nginx.org/en/docs/http/ngx_http_realip_module.html).
+
+A simple example is as follows:
+
+1. Create a configuration file for nginx, this can be global (in `conf.d`) or host specific (in `vhost.d`)
+2. Add your `realip` configuration:
+
+```nginx
+# Your proxy server ip address
+set_real_ip_from  192.168.1.0/24;
+
+# Where to replace `$remote_addr` and `$remote_port` from
+real_ip_header proxy_protocol;
+```
+
 ⬆️ [back to table of contents](#table-of-contents)
 
 ## Custom Nginx Configuration
@@ -1451,6 +1470,7 @@ curl -s -H "Host: test.nginx-proxy.tld" localhost/nginx-proxy-debug | jq
     "enable_debug_endpoint": "true",
     "enable_http2": "true",
     "enable_http3": "false",
+    "enable_proxy_protocol": "false",
     "enable_http_on_missing_cert": "true",
     "enable_ipv6": false,
     "enable_json_logs": false,

nginx.tmpl

@@ -31,6 +31,7 @@
 {{- $_ := set $config "acme_http_challenge_accept_unknown_host" ($globals.Env.ACME_HTTP_CHALLENGE_ACCEPT_UNKNOWN_HOST | default "false" | parseBool) }}
 {{- $_ := set $config "enable_http2" ($globals.Env.ENABLE_HTTP2 | default "true") }}
 {{- $_ := set $config "enable_http3" ($globals.Env.ENABLE_HTTP3 | default "false") }}
+{{- $_ := set $config "enable_proxy_protocol" ($globals.Env.ENABLE_PROXY_PROTOCOL | default "false" | parseBool) }}
 {{- $_ := set $config "enable_http_on_missing_cert" ($globals.Env.ENABLE_HTTP_ON_MISSING_CERT | default "true") }}
 {{- $_ := set $config "https_method" ($globals.Env.HTTPS_METHOD | default "redirect") }}
 {{- $_ := set $config "non_get_redirect" ($globals.Env.NON_GET_REDIRECT | default "301") }}
@@ -440,6 +441,19 @@ upstream {{ $vpath.upstream }} {
     {{- when .Enable "access_log /var/log/nginx/access.log vhost;" "" }}
 {{- end }}
 
+map $proxy_add_x_forwarded_for $proxy_x_forwarded_for {
+    {{- if $globals.config.trust_downstream_proxy }}
+        {{- if $globals.config.enable_proxy_protocol }}
+    default $proxy_protocol_addr;
+        {{- else }}
+    default $proxy_add_x_forwarded_for;
+        {{- end }}
+    {{- else }}
+    default $remote_addr;
+    {{- end }}
+    '' $remote_addr;
+}
+
 # If we receive X-Forwarded-Proto, pass it through; otherwise, pass along the
 # scheme used to connect to this server
 map $http_x_forwarded_proto $proxy_x_forwarded_proto {
@@ -454,8 +468,20 @@ map $http_x_forwarded_host $proxy_x_forwarded_host {
 
 # If we receive X-Forwarded-Port, pass it through; otherwise, pass along the
 # server port the client connected to
-map $http_x_forwarded_port $proxy_x_forwarded_port {
+map $http_x_forwarded_port $_proxy_x_forwarded_port {
-    default {{ if $globals.config.trust_downstream_proxy }}$http_x_forwarded_port{{ else }}$server_port{{ end }};
+    {{ if $globals.config.trust_downstream_proxy }}
+        {{ if $globals.config.enable_proxy_protocol }}
+    default $proxy_protocol_server_port;
+        {{- else }}
+    default $http_x_forwarded_port;
+        {{- end }}
+    {{- else }}
+    default $server_port;
+    {{- end }}
+}
+
+map $_proxy_x_forwarded_port $proxy_x_forwarded_port {
+    default $_proxy_x_forwarded_port;
     '' $server_port;
 }
 
@@ -559,7 +585,7 @@ proxy_set_header Host $host$host_port;
 proxy_set_header Upgrade $http_upgrade;
 proxy_set_header Connection $proxy_connection;
 proxy_set_header X-Real-IP $remote_addr;
-proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+proxy_set_header X-Forwarded-For $proxy_x_forwarded_for;
 proxy_set_header X-Forwarded-Host $proxy_x_forwarded_host;
 proxy_set_header X-Forwarded-Proto $proxy_x_forwarded_proto;
 proxy_set_header X-Forwarded-Ssl $proxy_x_forwarded_ssl;
@@ -821,6 +847,7 @@ proxy_set_header Proxy "";
         {{- $default_https_exists = or $default_https_exists (and $https $vhost.default) }}
         {{- $http3_enabled = or $http3_enabled $vhost.http3_enabled }}
     {{- end }}
+    {{- $proxy_protocol := when $globals.config.enable_proxy_protocol " proxy_protocol" "" }}
     {{- $fallback_http := not $default_http_exists }}
     {{- $fallback_https := not $default_https_exists }}
     {{- /*
@@ -838,21 +865,21 @@ server {
     {{ template "access_log" (dict "Enable" $globals.config.enable_access_log) }}
     http2 on;
         {{- if $fallback_http }}
-    listen {{ $globals.config.external_http_port }}; {{- /* Do not add `default_server` (see comment above). */}}
+    listen {{ $globals.config.external_http_port }} {{- $proxy_protocol }}; {{- /* Do not add `default_server` (see comment above). */}}
                 {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_http_port }}; {{- /* Do not add `default_server` (see comment above). */}}
+    listen [::]:{{ $globals.config.external_http_port }} {{- $proxy_protocol }}; {{- /* Do not add `default_server` (see comment above). */}}
                 {{- end }}
         {{- end }}
         {{- if $fallback_https }}
-    listen {{ $globals.config.external_https_port }} ssl; {{- /* Do not add `default_server` (see comment above). */}}
+    listen {{ $globals.config.external_https_port }} ssl {{- $proxy_protocol }}; {{- /* Do not add `default_server` (see comment above). */}}
             {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_https_port }} ssl; {{- /* Do not add `default_server` (see comment above). */}}
+    listen [::]:{{ $globals.config.external_https_port }} ssl {{- $proxy_protocol }}; {{- /* Do not add `default_server` (see comment above). */}}
             {{- end }}
             {{- if $http3_enabled }}
     http3 on;
-    listen {{ $globals.config.external_https_port }} quic reuseport; {{- /* Do not add `default_server` (see comment above). */}}
+    listen {{ $globals.config.external_https_port }} quic reuseport {{- $proxy_protocol }}; {{- /* Do not add `default_server` (see comment above). */}}
                 {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_https_port }} quic reuseport; {{- /* Do not add `default_server` (see comment above). */}}
+    listen [::]:{{ $globals.config.external_https_port }} quic reuseport {{- $proxy_protocol }}; {{- /* Do not add `default_server` (see comment above). */}}
                 {{- end }}
             {{- end }}
     ssl_session_cache shared:SSL:50m;
@@ -892,7 +919,8 @@ server {
 {{- end }}
 
 {{- range $hostname, $vhost := $globals.vhosts }}
-    {{- $default_server := when $vhost.default "default_server" "" }}
+    {{- $default_server := when $vhost.default " default_server" "" }}
+    {{- $proxy_protocol := when $globals.config.enable_proxy_protocol " proxy_protocol" "" }}
 
     {{- range $path, $vpath := $vhost.paths }}
 # {{ $hostname }}{{ $path }}
@@ -906,9 +934,9 @@ server {
     server_tokens {{ $vhost.server_tokens }};
         {{- end }}
     {{ template "access_log" (dict "Enable" $globals.config.enable_access_log) }}
-    listen {{ $globals.config.external_http_port }} {{ $default_server }};
+    listen {{ $globals.config.external_http_port }} {{- $default_server }} {{- $proxy_protocol }};
         {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_http_port }} {{ $default_server }};
+    listen [::]:{{ $globals.config.external_http_port }} {{- $default_server }} {{- $proxy_protocol }};
         {{- end }}
 
         {{- if (or $vhost.acme_http_challenge_legacy $vhost.acme_http_challenge_enabled) }}
@@ -967,9 +995,9 @@ server {
     http2 on;
     {{- end }}
     {{- if or (eq $vhost.https_method "nohttps") (eq $vhost.https_method "noredirect") }}
-    listen {{ $globals.config.external_http_port }} {{ $default_server }};
+    listen {{ $globals.config.external_http_port }} {{- $default_server }} {{- $proxy_protocol }};
         {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_http_port }} {{ $default_server }};
+    listen [::]:{{ $globals.config.external_http_port }} {{- $default_server }} {{- $proxy_protocol }};
         {{- end }}
 
         {{- if (and (eq $vhost.https_method "noredirect") $vhost.acme_http_challenge_enabled) }}
@@ -984,17 +1012,17 @@ server {
         {{- end }}
     {{- end }}
     {{- if ne $vhost.https_method "nohttps" }}
-    listen {{ $globals.config.external_https_port }} ssl {{ $default_server }};
+    listen {{ $globals.config.external_https_port }} ssl {{- $default_server }} {{- $proxy_protocol }};
         {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_https_port }} ssl {{ $default_server }};
+    listen [::]:{{ $globals.config.external_https_port }} ssl {{- $default_server }} {{- $proxy_protocol }};
         {{- end }}
 
         {{- if $vhost.http3_enabled }}
     http3 on;
     add_header alt-svc 'h3=":{{ $globals.config.external_https_port }}"; ma=86400;';
-    listen {{ $globals.config.external_https_port }} quic {{ $default_server }};
+    listen {{ $globals.config.external_https_port }} quic {{- $default_server }} {{- $proxy_protocol }};
             {{- if $globals.config.enable_ipv6 }}
-    listen [::]:{{ $globals.config.external_https_port }} quic {{ $default_server }};
+    listen [::]:{{ $globals.config.external_https_port }} quic {{- $default_server }} {{- $proxy_protocol }};
             {{- end }}
         {{- end }}
 

test/test_proxy_protocol/test_proxy-protocol-global-disabled.py

@@ -0,0 +1,58 @@
+import socket
+
+
+def test_proxy_protocol_global_disabled_X_Forwarded_For_is_generated(
+    docker_compose, nginxproxy
+):
+    r = nginxproxy.get("http://proxy-protocol-global-disabled.nginx-proxy.tld/headers")
+    assert r.status_code == 200
+    assert "X-Forwarded-For:" in r.text
+
+
+def test_proxy_protocol_global_disabled_X_Forwarded_For_is_passed_on(
+    docker_compose, nginxproxy
+):
+    r = nginxproxy.get(
+        "http://proxy-protocol-global-disabled.nginx-proxy.tld/headers",
+        headers={"X-Forwarded-For": "1.2.3.4"},
+    )
+    assert r.status_code == 200
+    assert "X-Forwarded-For: 1.2.3.4, " in r.text
+
+
+def test_proxy_protocol_global_disabled_X_Forwarded_Port_is_generated(
+    docker_compose, nginxproxy
+):
+    r = nginxproxy.get("http://proxy-protocol-global-disabled.nginx-proxy.tld/headers")
+    assert r.status_code == 200
+    assert "X-Forwarded-Port: 80\n" in r.text
+
+
+def test_proxy_protocol_global_disabled_X_Forwarded_Port_is_passed_on(
+    docker_compose, nginxproxy
+):
+    r = nginxproxy.get(
+        "http://proxy-protocol-global-disabled.nginx-proxy.tld/headers",
+        headers={"X-Forwarded-Port": "1234"},
+    )
+    assert r.status_code == 200
+    assert "X-Forwarded-Port: 1234\n" in r.text
+
+
+def test_proxy_protocol_global_disabled_proto_request_fails(docker_compose, nginxproxy):
+    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    client.connect((nginxproxy.get_ip(), 80))
+
+    # 1.2.3.4 is the client IP
+    # 4.3.2.1 is the proxy server IP
+    # 8080 is the client port
+    # 9090 is the proxy server port
+    client.send(f"PROXY TCP4 1.2.3.4 4.3.2.1 8080 9090\r\n".encode("utf-8"))
+    client.send(
+        "GET /headers HTTP/1.1\r\nHost: proxy-protocol-global-enabled.nginx-proxy.tld\r\n\r\n".encode(
+            "utf-8"
+        )
+    )
+
+    response = client.recv(4096).decode("utf-8")
+    assert "HTTP/1.1 400 Bad Request" in response

test/test_proxy_protocol/test_proxy-protocol-global-disabled.yml

@@ -0,0 +1,12 @@
+services:
+#  nginx-proxy:
+#    environment:
+#      ENABLE_PROXY_PROTOCOL: "false"    #Disabled by default
+
+  proxy-protocol-global-disabled:
+    image: web
+    expose:
+      - "80"
+    environment:
+      WEB_PORTS: "80"
+      VIRTUAL_HOST: proxy-protocol-global-disabled.nginx-proxy.tld

test/test_proxy_protocol/test_proxy-protocol-global-enabled.py

@@ -0,0 +1,31 @@
+import socket
+
+
+def test_proxy_protocol_global_enabled_normal_request_fails(docker_compose, nginxproxy):
+    try:
+        r = nginxproxy.get(
+            "http://proxy-protocol-global-enabled.nginx-proxy.tld/headers"
+        )
+        assert False
+    except Exception as e:
+        assert "Remote end closed connection without response" in str(e)
+
+
+def test_proxy_protocol_global_enabled_proto_request_works(docker_compose, nginxproxy):
+    client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    client.connect((nginxproxy.get_ip(), 80))
+
+    # 1.2.3.4 is the client IP
+    # 4.3.2.1 is the proxy server IP
+    # 8080 is the client port
+    # 9090 is the proxy server port
+    client.send(f"PROXY TCP4 1.2.3.4 4.3.2.1 8080 9090\r\n".encode("utf-8"))
+    client.send(
+        "GET /headers HTTP/1.1\r\nHost: proxy-protocol-global-enabled.nginx-proxy.tld\r\n\r\n".encode(
+            "utf-8"
+        )
+    )
+
+    response = client.recv(4096).decode("utf-8")
+    assert "X-Forwarded-For: 1.2.3.4" in response
+    assert "X-Forwarded-Port: 9090" in response

test/test_proxy_protocol/test_proxy-protocol-global-enabled.yml

@@ -0,0 +1,12 @@
+services:
+  nginx-proxy:
+    environment:
+      ENABLE_PROXY_PROTOCOL: "true"
+
+  proxy-protocol-global-enabled:
+    image: web
+    expose:
+      - "80"
+    environment:
+      WEB_PORTS: "80"
+      VIRTUAL_HOST: proxy-protocol-global-enabled.nginx-proxy.tld