From 4c64fcfe8e49219820eac266eb4319ee1e676604 Mon Sep 17 00:00:00 2001
From: Per Inge Mathisen <per@wz2100.net>
Date: Fri, 15 Feb 2008 21:18:13 +0000
Subject: [PATCH] Sanity check power sync packets, and add net log if power is
 changed. Add getPower() function to avoid direct access to asPower array.

git-svn-id: svn+ssh://svn.gna.org/svn/warzone/trunk@3789 4a71c877-e1ca-e34f-864e-861f7616d084
---
 src/multisync.c | 20 ++++++++++++++++----
 src/power.c     |  9 +++++++++
 src/power.h     |  3 +++
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/src/multisync.c b/src/multisync.c
index ea2d73f43..01412e64b 100644
--- a/src/multisync.c
+++ b/src/multisync.c
@@ -907,7 +907,7 @@ static BOOL sendPowerCheck()
 {
 	static UDWORD	lastsent = 0;
 	uint8_t			player = selectedPlayer;
-	uint32_t		power = asPower[player]->currentPower;
+	uint32_t		power = getPower(player);
 
 	if (lastsent > gameTime)
 	{
@@ -931,14 +931,26 @@ static BOOL sendPowerCheck()
 BOOL recvPowerCheck()
 {
 	uint8_t		player;
-	uint32_t	power;
+	uint32_t	power, power2;
 
 	NETbeginDecode(NET_CHECK_POWER);
 		NETuint8_t(&player);
 		NETuint32_t(&power);
 	NETend();
-	
-	setPower(player, power);
+
+	if (player >= MAX_PLAYERS)
+	{
+		debug(LOG_ERROR, "Bad NET_CHECK_POWER packet: player is %d", (int)player);
+		return FALSE;
+	}
+
+	power2 = getPower(player);
+	if (power != power2)
+	{
+		debug(LOG_NET, "NET_CHECK_POWER: Adjusting power for player %d from %u to %u", 
+		      (int)player, power2, power);
+		setPower(player, power);
+	}
 	return TRUE;
 }
 
diff --git a/src/power.c b/src/power.c
index ec3b95d88..e06ef7b37 100644
--- a/src/power.c
+++ b/src/power.c
@@ -337,6 +337,15 @@ void setPower(UDWORD player, UDWORD avail)
 	asPower[player]->currentPower = avail;
 }
 
+// only used in multiplayer games.
+UDWORD getPower(UDWORD player)
+{
+	ASSERT(player < MAX_PLAYERS, "setPower: Bad player (%u)", player);
+	ASSERT(asPower[player] != NULL, "asPower[player=%u] not allocated", player);
+
+	return asPower[player]->currentPower;
+}
+
 /*sets the initial value for the power*/
 void setPlayerPower(UDWORD power, UDWORD player)
 {
diff --git a/src/power.h b/src/power.h
index 120356b67..a3ab0e487 100644
--- a/src/power.h
+++ b/src/power.h
@@ -75,6 +75,9 @@ extern void updatePlayerPower(UDWORD player);
 // used in multiplayer to force power levels.
 extern void setPower(UDWORD player, UDWORD avail); 
 
+/** Get the amount of power current held by the given player. */
+extern UDWORD getPower(UDWORD player);
+
 /*resets the power levels for all players when power is turned back on*/
 void powerCalc(BOOL on);