feat: enable upstream PROXY protocol per TCP port

apisix/cli/ngx_tpl.lua

@@ -217,15 +217,48 @@ stream {
             require("resty.events.compat").run()
         }
     }
-
+    {% for _, item in ipairs(stream_proxy.tcp or {}) do %}
     server {
-        {% for _, item in ipairs(stream_proxy.tcp or {}) do %}
         listen {*item.addr*} {% if item.tls then %} ssl {% end %} {% if enable_reuseport then %} reuseport {% end %} {% if proxy_protocol and proxy_protocol.enable_tcp_pp then %} proxy_protocol {% end %};
+
+        {% if tcp_enable_ssl then %}
+        ssl_certificate      {* ssl.ssl_cert *};
+        ssl_certificate_key  {* ssl.ssl_cert_key *};
+
+        ssl_client_hello_by_lua_block {
+            apisix.ssl_client_hello_phase()
+        }
+
+        ssl_certificate_by_lua_block {
+            apisix.ssl_phase()
+        }
         {% end %}
-        {% for _, addr in ipairs(stream_proxy.udp or {}) do %}
-        listen {*addr*} udp {% if enable_reuseport then %} reuseport {% end %};
+
+        {% if (proxy_protocol and proxy_protocol.enable_tcp_pp_to_upstream) or item.proxy_protocol then %}
+        proxy_protocol on;
         {% end %}
 
+        preread_by_lua_block {
+            apisix.stream_preread_phase()
+        }
+
+        proxy_pass apisix_backend;
+
+        {% if use_apisix_base then %}
+        set $upstream_sni "apisix_backend";
+        proxy_ssl_server_name on;
+        proxy_ssl_name $upstream_sni;
+        {% end %}
+
+        log_by_lua_block {
+            apisix.stream_log_phase()
+        }
+    }
+    {% end %}
+    {% for _, addr in ipairs(stream_proxy.udp or {}) do %}
+    server {
+        listen {*addr*} udp {% if enable_reuseport then %} reuseport {% end %};
+
         {% if tcp_enable_ssl then %}
         ssl_certificate      {* ssl.ssl_cert *};
         ssl_certificate_key  {* ssl.ssl_cert_key *};
@@ -259,6 +292,7 @@ stream {
             apisix.stream_log_phase()
         }
     }
+    {% end %}
 }
 {% end %}
 

docs/en/latest/stream-proxy.md

@@ -241,3 +241,16 @@ curl http://127.0.0.1:9180/apisix/admin/stream_routes/1 -H "X-API-KEY: $admin_ke
 By setting the `scheme` to `tls`, APISIX will do TLS handshake with the upstream.
 
 When the client is also speaking TLS over TCP, the SNI from the client will pass through to the upstream. Otherwise, a dummy SNI `apisix_backend` will be used.
+
+## Enable upstream PROXY protocol per TCP port
+
+APISIX can enable upstream PROXY protocol for specific ports.
+
+```yaml
+apisix:
+  proxy_mode: http&stream  # enable both http and stream proxies
+  stream_proxy: # TCP/UDP proxy
+    tcp: # TCP proxy address list
+      - addr: 9100
+        proxy_protocol: true
+```

t/cli/test_stream_config.sh

@@ -109,3 +109,61 @@ if ! grep "plugin-limit-conn-stream" conf/nginx.conf > /dev/null; then
 fi
 
 echo "passed: enable shdict on demand"
+
+# Test: per-port proxy_protocol generates proxy_protocol on in the TCP server block
+echo "
+apisix:
+    proxy_mode: http&stream
+    stream_proxy:
+        tcp:
+            - addr: 9100
+              proxy_protocol: true
+" > conf/config.yaml
+
+make init
+
+if ! grep -q "proxy_protocol on" conf/nginx.conf; then
+    echo "failed: per-port proxy_protocol should generate 'proxy_protocol on' in nginx.conf"
+    exit 1
+fi
+
+echo "passed: per-port proxy_protocol generates proxy_protocol on"
+
+# Test: without per-port proxy_protocol flag, no proxy_protocol on in TCP server block
+echo "
+apisix:
+    proxy_mode: http&stream
+    stream_proxy:
+        tcp:
+            - addr: 9100
+" > conf/config.yaml
+
+make init
+
+if grep -q "proxy_protocol on" conf/nginx.conf; then
+    echo "failed: TCP port without proxy_protocol flag should not generate 'proxy_protocol on'"
+    exit 1
+fi
+
+echo "passed: TCP port without proxy_protocol flag does not generate proxy_protocol on"
+
+# Test: mixed ports - only flagged port gets proxy_protocol on
+echo "
+apisix:
+    proxy_mode: http&stream
+    stream_proxy:
+        tcp:
+            - addr: 9100
+              proxy_protocol: true
+            - addr: 9101
+" > conf/config.yaml
+
+make init
+
+count=$(grep -c "proxy_protocol on" conf/nginx.conf)
+if [ "$count" -ne 1 ]; then
+    echo "failed: only the flagged TCP port should generate 'proxy_protocol on', got $count occurrences"
+    exit 1
+fi
+
+echo "passed: only the flagged TCP port generates proxy_protocol on"