From a9213fd12c3325f86ac46b2e94a5da701407edf3 Mon Sep 17 00:00:00 2001
From: est31 <MTest31@outlook.com>
Date: Fri, 17 Jul 2015 06:52:46 +0200
Subject: [PATCH] Protocol 25: Repurpose string field for access denial

Send it always, and make client use it as fallback for unknown reason strings.

This gives us future-proof-ness.
---
 src/network/clientpackethandler.cpp |  6 ++++--
 src/network/networkprotocol.h       |  3 ++-
 src/server.cpp                      | 20 ++++++++++++++------
 src/server.h                        |  2 +-
 4 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/src/network/clientpackethandler.cpp b/src/network/clientpackethandler.cpp
index 15d5456fa..1c50a1dc6 100644
--- a/src/network/clientpackethandler.cpp
+++ b/src/network/clientpackethandler.cpp
@@ -217,9 +217,11 @@ void Client::handleCommand_AccessDenied(NetworkPacket* pkt)
 		*pkt >> denyCode;
 		if (denyCode == SERVER_ACCESSDENIED_CUSTOM_STRING) {
 			*pkt >> m_access_denied_reason;
-		}
-		else if (denyCode < SERVER_ACCESSDENIED_MAX) {
+		} else if (denyCode < SERVER_ACCESSDENIED_MAX) {
 			m_access_denied_reason = accessDeniedStrings[denyCode];
+		} else {
+			// Use the fallback string sent by the server
+			*pkt >> m_access_denied_reason;
 		}
 	}
 	// 13/03/15 Legacy code from 0.4.12 and lesser. must stay 1 year
diff --git a/src/network/networkprotocol.h b/src/network/networkprotocol.h
index e4b566740..6c51eabf6 100644
--- a/src/network/networkprotocol.h
+++ b/src/network/networkprotocol.h
@@ -202,7 +202,8 @@ enum ToClientCommand
 	TOCLIENT_ACCESS_DENIED = 0x0A,
 	/*
 		u8 reason
-		std::string custom reason (if reason == SERVER_ACCESSDENIED_CUSTOM_STRING)
+		std::string custom reason (if reason == SERVER_ACCESSDENIED_CUSTOM_STRING),
+			also used as string fallback for new reasons beyond the initial 10.
 	*/
 	TOCLIENT_BLOCKDATA = 0x20, //TODO: Multiple blocks
 	TOCLIENT_ADDNODE = 0x21,
diff --git a/src/server.cpp b/src/server.cpp
index 2d6de1c9d..6a3226d03 100644
--- a/src/server.cpp
+++ b/src/server.cpp
@@ -1523,16 +1523,17 @@ void Server::SendBreath(u16 peer_id, u16 breath)
 	Send(&pkt);
 }
 
-void Server::SendAccessDenied(u16 peer_id, AccessDeniedCode reason, const std::string &custom_reason)
+void Server::SendAccessDenied(u16 peer_id, AccessDeniedCode reason,
+		const std::string &str_reason)
 {
 	DSTACK(__FUNCTION_NAME);
 
 	NetworkPacket pkt(TOCLIENT_ACCESS_DENIED, 1, peer_id);
 	pkt << (u8) reason;
 
-	if (reason == SERVER_ACCESSDENIED_CUSTOM_STRING) {
-		pkt << custom_reason;
-	}
+	// Custom or fallback reason
+	pkt << str_reason;
+
 	Send(&pkt);
 }
 
@@ -2575,11 +2576,18 @@ void Server::DenySudoAccess(u16 peer_id)
 	Send(&pkt);
 }
 
-void Server::DenyAccess(u16 peer_id, AccessDeniedCode reason, const std::string &custom_reason)
+void Server::DenyAccess(u16 peer_id, AccessDeniedCode reason,
+		const std::string &custom_reason)
 {
 	DSTACK(__FUNCTION_NAME);
 
-	SendAccessDenied(peer_id, reason, custom_reason);
+	if((u8) reason > 10) {
+		// Send fallback
+		SendAccessDenied(peer_id, reason, accessDeniedStrings[(u8) reason]);
+	} else {
+		SendAccessDenied(peer_id, reason, custom_reason);
+	}
+
 	m_clients.event(peer_id, CSE_SetDenied);
 	m_con.DisconnectPeer(peer_id);
 }
diff --git a/src/server.h b/src/server.h
index fbca05f26..19975b768 100644
--- a/src/server.h
+++ b/src/server.h
@@ -390,7 +390,7 @@ private:
 	void SendMovement(u16 peer_id);
 	void SendHP(u16 peer_id, u8 hp);
 	void SendBreath(u16 peer_id, u16 breath);
-	void SendAccessDenied(u16 peer_id, AccessDeniedCode reason, const std::string &custom_reason);
+	void SendAccessDenied(u16 peer_id, AccessDeniedCode reason, const std::string &str_reason);
 	void SendAccessDenied_Legacy(u16 peer_id, const std::wstring &reason);
 	void SendDeathscreen(u16 peer_id,bool set_camera_point_target, v3f camera_point_target);
 	void SendItemDef(u16 peer_id,IItemDefManager *itemdef, u16 protocol_version);