From cd4a027eac9a198ef6b1a7ec7e3a3abf74683385 Mon Sep 17 00:00:00 2001
From: WebFreak001 <janju007@web.de>
Date: Fri, 11 Aug 2017 06:26:52 +0200
Subject: [PATCH] Undo some changes in main

---
 src/common/messages.d |  2 +-
 src/server/main.d     | 49 ++++++++++++++++++++++++++++++++++++-------
 2 files changed, 42 insertions(+), 9 deletions(-)

diff --git a/src/common/messages.d b/src/common/messages.d
index 411c70b..3287758 100644
--- a/src/common/messages.d
+++ b/src/common/messages.d
@@ -167,7 +167,7 @@ struct AutocompleteResponse
 	ulong symbolIdentifier;
 
 	/**
-	 * Creates an empty acknoledgement response
+	 * Creates an empty acknowledgement response
 	 */
 	static AutocompleteResponse ack()
 	{
diff --git a/src/server/main.d b/src/server/main.d
index 3a01e7c..1bc688d 100644
--- a/src/server/main.d
+++ b/src/server/main.d
@@ -131,7 +131,7 @@ int main(string[] args)
 		socket = new TcpSocket(AddressFamily.INET);
 		socket.blocking = true;
 		socket.setOption(SocketOptionLevel.SOCKET, SocketOption.REUSEADDR, true);
-		socket.bind(new InternetAddress("127.0.0.1", port));
+		socket.bind(new InternetAddress("localhost", port));
 		info("Listening on port ", port);
 	}
 	else
@@ -182,21 +182,40 @@ int main(string[] args)
 	// No relative paths
 	version (Posix) chdir("/");
 
+	version (LittleEndian)
+		immutable expectedClient = IPv4Union([1, 0, 0, 127]);
+	else
+		immutable expectedClient = IPv4Union([127, 0, 0, 1]);
+
 	serverLoop: while (true)
 	{
 		auto s = socket.accept();
 		s.blocking = true;
 
+		if (useTCP)
+		{
+			// Only accept connections from localhost
+			IPv4Union actual;
+			InternetAddress clientAddr = cast(InternetAddress) s.remoteAddress();
+			actual.i = clientAddr.addr;
+			// Shut down if somebody tries connecting from outside
+			if (actual.i != expectedClient.i)
+			{
+				fatal("Connection attempted from ", clientAddr.toAddrString());
+				return 1;
+			}
+		}
+
 		scope (exit)
 		{
 			s.shutdown(SocketShutdown.BOTH);
 			s.close();
 		}
 
-		sw.reset();
-		sw.start();
-
 		auto bytesReceived = s.receive(buffer);
+
+		auto requestWatch = StopWatch(AutoStart.yes);
+
 		size_t messageLength;
 		// bit magic!
 		(cast(ubyte*) &messageLength)[0..size_t.sizeof] = buffer[0..size_t.sizeof];
@@ -205,12 +224,18 @@ int main(string[] args)
 			immutable b = s.receive(buffer[bytesReceived .. $]);
 			if (b == Socket.ERROR)
 			{
-				warning("Socket recieve failed");
-				continue serverLoop;
+				bytesReceived = Socket.ERROR;
+				break;
 			}
 			bytesReceived += b;
 		}
 
+		if (bytesReceived == Socket.ERROR)
+		{
+			warning("Socket recieve failed");
+			break;
+		}
+
 		AutocompleteRequest request;
 		msgpack.unpack(buffer[size_t.sizeof .. bytesReceived], request);
 
@@ -259,12 +284,20 @@ int main(string[] args)
 		else if (request.kind & RequestKind.localUse)
 			s.trySendResponse(findLocalUse(request, cache), "Could not find local usage");
 
-		sw.stop();
-		info("Request processed in ", sw.peek().to!("msecs", float), " milliseconds");
+		info("Request processed in ", requestWatch.peek().to!("msecs", float), " milliseconds");
 	}
 	return 0;
 }
 
+/// IP v4 address as bytes and a uint
+union IPv4Union
+{
+	/// the bytes
+	ubyte[4] b;
+	/// the uint
+	uint i;
+}
+
 /// Lazily evaluates a response with an exception handler and sends it to a socket or logs msg if evaluating response fails.
 void trySendResponse(Socket socket, lazy AutocompleteResponse response, string msg)
 {