From 0f17e031e85dc7359ce1a0cbb842b07d2b2aa82a Mon Sep 17 00:00:00 2001
From: redpanther <redpanther@spooky-online.de>
Date: Thu, 18 Feb 2016 10:32:38 +0100
Subject: [PATCH] basic loop connection detection. prevent if you configure
 forward to 127.0.0.1:<port> and your server has the same port. But this
 doesn't protect if not forwarded to localhost "127.0.0.1". Loop connections
 across different hosts arn't detected too.

Former-commit-id: 464a80708ebd11c0f7c83dc87a1afe0f10e0e078
---
 libsrc/jsonserver/JsonServer.cpp   | 8 ++++++++
 libsrc/protoserver/ProtoServer.cpp | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/libsrc/jsonserver/JsonServer.cpp b/libsrc/jsonserver/JsonServer.cpp
index 4efe855c..4cd7f411 100644
--- a/libsrc/jsonserver/JsonServer.cpp
+++ b/libsrc/jsonserver/JsonServer.cpp
@@ -16,6 +16,14 @@ JsonServer::JsonServer(Hyperion *hyperion, uint16_t port) :
 		throw std::runtime_error("Json server could not bind to port");
 	}
 
+		QList<MessageForwarder::JsonSlaveAddress> list = _hyperion->getForwarder()->getJsonSlaves();
+		for ( int i=0; i<list.size(); i++ )
+		{
+			if ( list.at(i).addr == QHostAddress::LocalHost && list.at(i).port == port ) {
+				throw std::runtime_error("Loop between proto server and forwarder detected. Fix your config!");
+			}
+		}
+
 	// Set trigger for incoming connections
 	connect(&_server, SIGNAL(newConnection()), this, SLOT(newConnection()));
 
diff --git a/libsrc/protoserver/ProtoServer.cpp b/libsrc/protoserver/ProtoServer.cpp
index 03c334d4..c4eb82ca 100644
--- a/libsrc/protoserver/ProtoServer.cpp
+++ b/libsrc/protoserver/ProtoServer.cpp
@@ -18,6 +18,10 @@ ProtoServer::ProtoServer(Hyperion *hyperion, uint16_t port) :
 	QStringList slaves = forwarder->getProtoSlaves();
 
 	for (int i = 0; i < slaves.size(); ++i) {
+		if ( QString("127.0.0.1:%1").arg(port) == slaves.at(i) ) {
+			throw std::runtime_error("Loop between proto server and forwarder detected. Fix your config!");
+		}
+
 		ProtoConnection* p = new ProtoConnection(slaves.at(i).toLocal8Bit().constData());
 		p->setSkipReply(true);
 		_proxy_connections << p;