Add `server.tomcat.port-header` support

Update Tomcat ServerProperties to support the RemoteIpValve portHeader
property.

Fixes gh-1616

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ServerProperties.java

@@ -209,6 +209,8 @@ public class ServerProperties implements EmbeddedServletContainerCustomizer {
 
 		private String protocolHeader;
 
+		private String portHeader;
+
 		private String remoteIpHeader;
 
 		private File basedir;
@@ -285,6 +287,14 @@ public class ServerProperties implements EmbeddedServletContainerCustomizer {
 			this.protocolHeader = protocolHeader;
 		}
 
+		public String getPortHeader() {
+			return this.portHeader;
+		}
+
+		public void setPortHeader(String portHeader) {
+			this.portHeader = portHeader;
+		}
+
 		public String getRemoteIpHeader() {
 			return this.remoteIpHeader;
 		}
@@ -321,6 +331,7 @@ public class ServerProperties implements EmbeddedServletContainerCustomizer {
 				valve.setRemoteIpHeader(remoteIpHeader);
 				valve.setProtocolHeader(protocolHeader);
 				valve.setInternalProxies(getInternalProxies());
+				valve.setPortHeader(getPortHeader());
 				factory.addContextValves(valve);
 			}
 

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/ServerPropertiesTests.java

@@ -177,6 +177,7 @@ public class ServerPropertiesTests {
 		map.put("server.tomcat.remote_ip_header", "x-my-remote-ip-header");
 		map.put("server.tomcat.protocol_header", "x-my-protocol-header");
 		map.put("server.tomcat.internal_proxies", "192.168.0.1");
+		map.put("server.tomcat.port-header", "x-my-forward-port");
 		bindProperties(map);
 
 		TomcatEmbeddedServletContainerFactory container = new TomcatEmbeddedServletContainerFactory();
@@ -188,6 +189,7 @@ public class ServerPropertiesTests {
 		RemoteIpValve remoteIpValve = (RemoteIpValve) valve;
 		assertEquals("x-my-protocol-header", remoteIpValve.getProtocolHeader());
 		assertEquals("x-my-remote-ip-header", remoteIpValve.getRemoteIpHeader());
+		assertEquals("x-my-forward-port", remoteIpValve.getPortHeader());
 		assertEquals("192.168.0.1", remoteIpValve.getInternalProxies());
 	}
 

spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -74,7 +74,8 @@ content into your application; rather pick only the properties that you need.
 			192\.168\.\d{1,3}\.\d{1,3}|\
 			169\.254\.\d{1,3}\.\d{1,3}|\
 			127\.\d{1,3}\.\d{1,3}\.\d{1,3} # regular expression matching trusted IP addresses
-	server.tomcat.protocol-header=x-forwarded-proto # ssl forward headers
+	server.tomcat.protocol-header=x-forwarded-proto # front end proxy forward header
+	server.tomcat.port-header= # front end proxy port header
 	server.tomcat.remote-ip-header=x-forwarded-for
 	server.tomcat.basedir=/tmp # base dir (usually not needed, defaults to tmp)
 	server.tomcat.background-processor-delay=30; # in seconds