From 8d017f0ea1e21276d00f3325acd71e40c53cfc39 Mon Sep 17 00:00:00 2001
From: rubidium <rubidium@openttd.org>
Date: Wed, 7 Jan 2009 15:27:19 +0000
Subject: [PATCH] (svn r14897) -Codechange: don't allow a few command flags to
 be sent over the network as it's bogus information anyway; e.g. the "do not
 send over network" flag as it will be set whenever the command is received
 from the server/client. -Codechange: test earlier whether the command (send
 from the server) is actually valid.

---
 src/command.cpp                |  2 +-
 src/network/network_client.cpp | 18 ++++++++++++++++++
 src/network/network_data.cpp   |  2 ++
 src/network/network_server.cpp |  5 +++++
 4 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/command.cpp b/src/command.cpp
index 03a7d3c807..08a9269aa5 100644
--- a/src/command.cpp
+++ b/src/command.cpp
@@ -560,7 +560,7 @@ bool DoCommandP(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallbac
 	if (_networking && !(cmd & CMD_NETWORK_COMMAND)) {
 		CompanyID bck = _local_company;
 		if (_network_dedicated || (_network_server && bck == COMPANY_SPECTATOR)) _local_company = COMPANY_FIRST;
-		NetworkSend_Command(tile, p1, p2, cmd, callback, text);
+		NetworkSend_Command(tile, p1, p2, cmd & ~CMD_FLAGS_MASK, callback, text);
 		if (_network_dedicated || (_network_server && bck == COMPANY_SPECTATOR)) _local_company = bck;
 		_docommand_recursive = 0;
 		ClearStorageChanges(false);
diff --git a/src/network/network_client.cpp b/src/network/network_client.cpp
index 2d7256beb8..1c56fda7c3 100644
--- a/src/network/network_client.cpp
+++ b/src/network/network_client.cpp
@@ -685,6 +685,24 @@ DEF_CLIENT_RECEIVE_COMMAND(PACKET_SERVER_COMMAND)
 	cp->my_cmd   = p->Recv_bool();
 	cp->next     = NULL;
 
+	if (!IsValidCommand(cp->cmd)) {
+		IConsolePrintF(CC_ERROR, "WARNING: invalid command from server, dropping...");
+		free(cp);
+		return NETWORK_RECV_STATUS_MALFORMED_PACKET;
+	}
+
+	if (GetCommandFlags(cp->cmd) & CMD_OFFLINE) {
+		IConsolePrintF(CC_ERROR, "WARNING: offline only command from server, dropping...");
+		free(cp);
+		return NETWORK_RECV_STATUS_MALFORMED_PACKET;
+	}
+
+	if ((cp->cmd & CMD_FLAGS_MASK) != 0) {
+		IConsolePrintF(CC_ERROR, "WARNING: invalid command flag from server, dropping...");
+		free(cp);
+		return NETWORK_RECV_STATUS_MALFORMED_PACKET;
+	}
+
 	// The server did send us this command..
 	//  queue it in our own queue, so we can handle it in the upcoming frame!
 
diff --git a/src/network/network_data.cpp b/src/network/network_data.cpp
index cdcf0ba399..c56c7905f0 100644
--- a/src/network/network_data.cpp
+++ b/src/network/network_data.cpp
@@ -34,6 +34,8 @@ void NetworkAddCommandQueue(NetworkClientSocket *cs, CommandPacket *cp)
 // Prepare a DoCommand to be send over the network
 void NetworkSend_Command(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallback *callback, const char *text)
 {
+	assert((cmd & CMD_FLAG_MASK) == 0);
+
 	CommandPacket c;
 
 	c.company = _local_company;
diff --git a/src/network/network_server.cpp b/src/network/network_server.cpp
index 2fc06f4a1b..e496bb6a56 100644
--- a/src/network/network_server.cpp
+++ b/src/network/network_server.cpp
@@ -839,6 +839,11 @@ static bool CheckCommandFlags(const CommandPacket *cp, const NetworkClientInfo *
 		return false;
 	}
 
+	if ((cp->cmd & CMD_FLAGS_MASK) != 0) {
+		IConsolePrintF(CC_ERROR, "WARNING: invalid command flag from client %d (IP: %s), kicking...", ci->client_id, GetClientIP(ci));
+		return false;
+	}
+
 	return true;
 }