Merge branch 'main' of https://github.com/smartcmd/MinecraftConsoles into fix-packet-vulns-v1

.gitignore

@@ -433,3 +433,6 @@ build/*
 
 # Local saves
 Minecraft.Client/Saves/
+
+# Visual Studio Per-User Config
+*.user

Minecraft.Client/ClientConnection.cpp

@@ -759,6 +759,18 @@ void ClientConnection::handleAddPlayer(shared_ptr<AddPlayerPacket> packet)
 			return;
 		}
 	}
+#ifdef _WINDOWS64
+	// Win64 keeps local-player identity separate from network smallId; also guard against creating
+	// a duplicate remote player for a local slot by checking the username directly.
+	for (unsigned int idx = 0; idx < XUSER_MAX_COUNT; ++idx)
+	{
+		if (minecraft->localplayers[idx] != NULL && minecraft->localplayers[idx]->name == packet->name)
+		{
+			app.DebugPrintf("AddPlayerPacket received for local player name %ls\n", packet->name.c_str());
+			return;
+		}
+	}
+#endif
 /*#ifdef _WINDOWS64
 	// On Windows64 all XUIDs are INVALID_XUID so the XUID check above never fires.
 	// packet->m_playerIndex is the server-assigned sequential index (set via LoginPacket),
@@ -800,22 +812,50 @@ void ClientConnection::handleAddPlayer(shared_ptr<AddPlayerPacket> packet)
 
 #ifdef _WINDOWS64
 	{
+		IQNetPlayer* matchedQNetPlayer = NULL;
 		PlayerUID pktXuid = player->getXuid();
 		const PlayerUID WIN64_XUID_BASE = (PlayerUID)0xe000d45248242f2e;
+		// Legacy compatibility path for peers still using embedded smallId XUIDs.
 		if (pktXuid >= WIN64_XUID_BASE && pktXuid < WIN64_XUID_BASE + MINECRAFT_NET_MAX_PLAYERS)
 		{
 			BYTE smallId = (BYTE)(pktXuid - WIN64_XUID_BASE);
 			INetworkPlayer* np = g_NetworkManager.GetPlayerBySmallId(smallId);
 			if (np != NULL)
 			{
+				NetworkPlayerXbox* npx = (NetworkPlayerXbox*)np;
+				matchedQNetPlayer = npx->GetQNetPlayer();
+			}
+		}
+
+		// Current Win64 path: identify QNet player by name and attach packet XUID.
+		if (matchedQNetPlayer == NULL)
+		{
+			for (BYTE smallId = 0; smallId < MINECRAFT_NET_MAX_PLAYERS; ++smallId)
+			{
+				INetworkPlayer* np = g_NetworkManager.GetPlayerBySmallId(smallId);
+				if (np == NULL)
+					continue;
+
 				NetworkPlayerXbox* npx = (NetworkPlayerXbox*)np;
 				IQNetPlayer* qp = npx->GetQNetPlayer();
-				if (qp != NULL && qp->m_gamertag[0] == 0)
+				if (qp != NULL && _wcsicmp(qp->m_gamertag, packet->name.c_str()) == 0)
 				{
-					wcsncpy_s(qp->m_gamertag, 32, packet->name.c_str(), _TRUNCATE);
+					matchedQNetPlayer = qp;
+					break;
 				}
 			}
 		}
+
+		if (matchedQNetPlayer != NULL)
+		{
+			// Store packet-authoritative XUID on this network slot so later lookups by XUID
+			// (e.g. remove player, display mapping) work for both legacy and uid.dat clients.
+			matchedQNetPlayer->m_resolvedXuid = pktXuid;
+			if (matchedQNetPlayer->m_gamertag[0] == 0)
+			{
+				wcsncpy_s(matchedQNetPlayer->m_gamertag, 32, packet->name.c_str(), _TRUNCATE);
+			}
+		}
 	}
 #endif
 
@@ -985,6 +1025,8 @@ void ClientConnection::handleRemoveEntity(shared_ptr<RemoveEntitiesPacket> packe
 							qp->m_smallId = 0;
 							qp->m_isRemote = false;
 							qp->m_isHostPlayer = false;
+							// Clear resolved id to avoid stale XUID -> player matches after disconnect.
+							qp->m_resolvedXuid = INVALID_XUID;
 							qp->m_gamertag[0] = 0;
 							qp->SetCustomDataValue(0);
 						}
@@ -3956,4 +3998,4 @@ ClientConnection::DeferredEntityLinkPacket::DeferredEntityLinkPacket(shared_ptr<
 {
 	m_recievedTick = GetTickCount();
 	m_packet = packet;
-}
+}

Minecraft.Client/Common/Audio/SoundEngine.cpp

@@ -260,7 +260,7 @@ void SoundEngine::updateMiniAudio()
             continue;
         }
 
-        float finalVolume = s->info.volume;
+        float finalVolume = s->info.volume * m_MasterEffectsVolume;
         if (finalVolume > 1.0f)
             finalVolume = 1.0f;
 
@@ -967,14 +967,8 @@ void SoundEngine::playMusicTick()
 // AP - moved to a separate function so it can be called from the mixer callback on Vita
 void SoundEngine::playMusicUpdate() 
 {
-	//return;
-	static bool firstCall = true;
 	static float fMusicVol = 0.0f;
-	if( firstCall )
-	{
-		fMusicVol = getMasterMusicVolume();
-		firstCall = false;
-	}
+	fMusicVol = getMasterMusicVolume();
 
 	switch(m_StreamState)
 	{
@@ -1242,7 +1236,7 @@ void SoundEngine::playMusicUpdate()
 
 			ma_sound_set_pitch(&m_musicStream, m_StreamingAudioInfo.pitch);
 
-			float finalVolume = m_StreamingAudioInfo.volume * m_MasterMusicVolume;
+			float finalVolume = m_StreamingAudioInfo.volume * getMasterMusicVolume();
 
 			ma_sound_set_volume(&m_musicStream, finalVolume);
 			ma_result startResult = ma_sound_start(&m_musicStream);
@@ -1370,14 +1364,11 @@ void SoundEngine::playMusicUpdate()
 				}
 
 				// volume change required?
-				if (fMusicVol != getMasterMusicVolume())
+				if (m_musicStreamActive)
 				{
-					if (m_musicStreamActive)
-					{
-						float finalVolume = m_StreamingAudioInfo.volume * fMusicVol;
+					float finalVolume = m_StreamingAudioInfo.volume * fMusicVol;
 
-						ma_sound_set_volume(&m_musicStream, finalVolume);
-					}
+					ma_sound_set_volume(&m_musicStream, finalVolume);
 				}
 			}
 		}

Minecraft.Client/Common/Consoles_App.cpp

@@ -2441,10 +2441,10 @@ void CMinecraftApp::ClearGameSettingsChangedFlag(int iPad)
 
 ///////////////////////////
 //
-// Remove the debug settings in the content package build
+// Remove the debug settings in the release build
 //
 ////////////////////////////
-#ifndef _DEBUG_MENUS_ENABLED
+#ifndef _DEBUG
 unsigned int CMinecraftApp::GetGameSettingsDebugMask(int iPad,bool bOverridePlayer) //bOverridePlayer is to force the send for the server to get the read options
 {
 	return 0;

Minecraft.Client/Common/Network/PlatformNetworkManagerStub.cpp

@@ -5,6 +5,7 @@
 #include "..\..\Xbox\Network\NetworkPlayerXbox.h"
 #ifdef _WINDOWS64
 #include "..\..\Windows64\Network\WinsockNetLayer.h"
+#include "..\..\Windows64\Windows64_Xuid.h"
 #include "..\..\Minecraft.h"
 #include "..\..\User.h"
 #include <iostream>
@@ -234,6 +235,7 @@ void CPlatformNetworkManagerStub::DoWork()
 				qnetPlayer->m_smallId = 0;
 				qnetPlayer->m_isRemote = false;
 				qnetPlayer->m_isHostPlayer = false;
+				qnetPlayer->m_resolvedXuid = INVALID_XUID;
 				qnetPlayer->m_gamertag[0] = 0;
 				qnetPlayer->SetCustomDataValue(0);
 				WinsockNetLayer::PushFreeSmallId(disconnectedSmallId);
@@ -354,7 +356,9 @@ void CPlatformNetworkManagerStub::HostGame(int localUsersMask, bool bOnlineGame,
 #ifdef _WINDOWS64
 	IQNet::m_player[0].m_smallId = 0;
 	IQNet::m_player[0].m_isRemote = false;
+	// world host is pinned to legacy host XUID to keep old player data compatibility.
 	IQNet::m_player[0].m_isHostPlayer = true;
+	IQNet::m_player[0].m_resolvedXuid = Win64Xuid::GetLegacyEmbeddedHostXuid();
 	IQNet::s_playerCount = 1;
 #endif
 
@@ -411,6 +415,8 @@ int CPlatformNetworkManagerStub::JoinGame(FriendSessionInfo* searchResult, int l
 	IQNet::m_player[0].m_smallId = 0;
 	IQNet::m_player[0].m_isRemote = true;
 	IQNet::m_player[0].m_isHostPlayer = true;
+	// Remote host still maps to legacy host XUID in mixed old/new sessions.
+	IQNet::m_player[0].m_resolvedXuid = Win64Xuid::GetLegacyEmbeddedHostXuid();
 	wcsncpy_s(IQNet::m_player[0].m_gamertag, 32, searchResult->data.hostName, _TRUNCATE);
 
 	WinsockNetLayer::StopDiscovery();
@@ -426,6 +432,8 @@ int CPlatformNetworkManagerStub::JoinGame(FriendSessionInfo* searchResult, int l
 	IQNet::m_player[localSmallId].m_smallId = localSmallId;
 	IQNet::m_player[localSmallId].m_isRemote = false;
 	IQNet::m_player[localSmallId].m_isHostPlayer = false;
+	// Local non-host identity is the persistent uid.dat XUID.
+	IQNet::m_player[localSmallId].m_resolvedXuid = Win64Xuid::ResolvePersistentXuid();
 
 	Minecraft* pMinecraft = Minecraft::GetInstance();
 	wcscpy_s(IQNet::m_player[localSmallId].m_gamertag, 32, pMinecraft->user->name.c_str());

Minecraft.Client/Common/UI/UIScene_HelpAndOptionsMenu.cpp

@@ -23,7 +23,7 @@ UIScene_HelpAndOptionsMenu::UIScene_HelpAndOptionsMenu(int iPad, void *initData,
 	// We don't have a reinstall content, so remove the button
 	removeControl( &m_buttons[BUTTON_HAO_REINSTALL], false );
 
-#ifdef _FINAL_BUILD
+#ifndef _DEBUG
 	removeControl( &m_buttons[BUTTON_HAO_DEBUG], false);
 #else
 	if(!app.DebugSettingsOn()) removeControl( &m_buttons[BUTTON_HAO_DEBUG], false);

Minecraft.Client/Extrax64Stubs.cpp

@@ -21,6 +21,7 @@
 #include "Windows64\Social\SocialManager.h"
 #include "Windows64\Sentient\DynamicConfigurations.h"
 #include "Windows64\Network\WinsockNetLayer.h"
+#include "Windows64\Windows64_Xuid.h"
 #elif defined __PSVITA__
 #include "PSVita\Sentient\SentientManager.h"
 #include "StatsCounter.h"
@@ -200,7 +201,15 @@ DWORD IQNetPlayer::GetCurrentRtt() { return 0; }
 bool IQNetPlayer::IsHost() { return m_isHostPlayer; }
 bool IQNetPlayer::IsGuest() { return false; }
 bool IQNetPlayer::IsLocal() { return !m_isRemote; }
-PlayerUID IQNetPlayer::GetXuid() { return (PlayerUID)(0xe000d45248242f2e + m_smallId); } // todo: restore to INVALID_XUID once saves support this
+PlayerUID IQNetPlayer::GetXuid()
+{
+	// Compatibility model:
+	// - Preferred path: use per-player resolved XUID populated from login/add-player flow.
+	// - Fallback path: keep legacy base+smallId behavior for peers/saves still on old scheme.
+	if (m_resolvedXuid != INVALID_XUID)
+		return m_resolvedXuid;
+	return (PlayerUID)(0xe000d45248242f2e + m_smallId);
+}
 LPCWSTR IQNetPlayer::GetGamertag() { return m_gamertag; }
 int IQNetPlayer::GetSessionIndex() { return m_smallId; }
 bool IQNetPlayer::IsTalking() { return false; }
@@ -226,6 +235,7 @@ void Win64_SetupRemoteQNetPlayer(IQNetPlayer * player, BYTE smallId, bool isHost
 	player->m_smallId = smallId;
 	player->m_isRemote = !isLocal;
 	player->m_isHostPlayer = isHost;
+	player->m_resolvedXuid = INVALID_XUID;
 	swprintf_s(player->m_gamertag, 32, L"Player%d", smallId);
 	if (smallId >= IQNet::s_playerCount)
 		IQNet::s_playerCount = smallId + 1;
@@ -285,8 +295,13 @@ IQNetPlayer* IQNet::GetPlayerByXuid(PlayerUID xuid)
 {
 	for (DWORD i = 0; i < s_playerCount; i++)
 	{
-		if (Win64_IsActivePlayer(&m_player[i], i) && m_player[i].GetXuid() == xuid) return &m_player[i];
+		if (!Win64_IsActivePlayer(&m_player[i], i))
+			continue;
+
+		if (m_player[i].GetXuid() == xuid)
+			return &m_player[i];
 	}
+	// Keep existing stub behavior: return host slot instead of NULL on miss.
 	return &m_player[0];
 }
 DWORD IQNet::GetPlayerCount()
@@ -301,7 +316,13 @@ DWORD IQNet::GetPlayerCount()
 QNET_STATE IQNet::GetState() { return _iQNetStubState; }
 bool IQNet::IsHost() { return s_isHosting; }
 HRESULT IQNet::JoinGameFromInviteInfo(DWORD dwUserIndex, DWORD dwUserMask, const INVITE_INFO * pInviteInfo) { return S_OK; }
-void IQNet::HostGame() { _iQNetStubState = QNET_STATE_SESSION_STARTING; s_isHosting = true; }
+void IQNet::HostGame()
+{
+	_iQNetStubState = QNET_STATE_SESSION_STARTING;
+	s_isHosting = true;
+	// Host slot keeps legacy XUID so old host player data remains addressable.
+	m_player[0].m_resolvedXuid = Win64Xuid::GetLegacyEmbeddedHostXuid();
+}
 void IQNet::ClientJoinGame()
 {
 	_iQNetStubState = QNET_STATE_SESSION_STARTING;
@@ -312,6 +333,7 @@ void IQNet::ClientJoinGame()
 		m_player[i].m_smallId = (BYTE)i;
 		m_player[i].m_isRemote = true;
 		m_player[i].m_isHostPlayer = false;
+		m_player[i].m_resolvedXuid = INVALID_XUID;
 		m_player[i].m_gamertag[0] = 0;
 		m_player[i].SetCustomDataValue(0);
 	}
@@ -326,6 +348,7 @@ void IQNet::EndGame()
 		m_player[i].m_smallId = (BYTE)i;
 		m_player[i].m_isRemote = false;
 		m_player[i].m_isHostPlayer = false;
+		m_player[i].m_resolvedXuid = INVALID_XUID;
 		m_player[i].m_gamertag[0] = 0;
 		m_player[i].SetCustomDataValue(0);
 	}
@@ -575,10 +598,13 @@ void				C_4JProfile::GetXUID(int iPad, PlayerUID * pXuid, bool bOnlineXuid)
 		*pXuid = INVALID_XUID;
 		return;
 	}
+	// LoginPacket reads this value as client identity:
+	// - host keeps legacy host XUID for world compatibility
+	// - non-host uses persistent uid.dat-backed XUID
 	if (IQNet::s_isHosting)
-		*pXuid = 0xe000d45248242f2e;
+		*pXuid = Win64Xuid::GetLegacyEmbeddedHostXuid();
 	else
-		*pXuid = 0xe000d45248242f2e + WinsockNetLayer::GetLocalSmallId();
+		*pXuid = Win64Xuid::ResolvePersistentXuid();
 #else
 	* pXuid = 0xe000d45248242f2e + iPad;
 #endif

Minecraft.Client/Minecraft.Client.vcxproj.user

@@ -1,22 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <PropertyGroup>
-    <LastConfigDeployed>Debug</LastConfigDeployed>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
-    <LocalDebuggerWorkingDirectory>$(SolutionDir)$(Platform)\$(Configuration)\</LocalDebuggerWorkingDirectory>
-    <DebuggerFlavor>WindowsLocalDebugger</DebuggerFlavor>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|ARM64EC'">
-    <LocalDebuggerWorkingDirectory>$(SolutionDir)$(Platform)\$(Configuration)\</LocalDebuggerWorkingDirectory>
-    <DebuggerFlavor>WindowsLocalDebugger</DebuggerFlavor>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
-    <LocalDebuggerWorkingDirectory>$(SolutionDir)$(Platform)\$(Configuration)\</LocalDebuggerWorkingDirectory>
-    <DebuggerFlavor>WindowsLocalDebugger</DebuggerFlavor>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|ARM64EC'">
-    <LocalDebuggerWorkingDirectory>$(SolutionDir)$(Platform)\$(Configuration)\</LocalDebuggerWorkingDirectory>
-    <DebuggerFlavor>WindowsLocalDebugger</DebuggerFlavor>
-  </PropertyGroup>
-</Project>

Minecraft.Client/Minecraft.cpp

@@ -52,6 +52,7 @@
 #include "..\Minecraft.World\net.minecraft.world.level.dimension.h"
 #include "..\Minecraft.World\net.minecraft.world.item.h"
 #include "..\Minecraft.World\Minecraft.World.h"
+#include "Windows64\Windows64_Xuid.h"
 #include "ClientConnection.h"
 #include "..\Minecraft.World\HellRandomLevelSource.h"
 #include "..\Minecraft.World\net.minecraft.world.entity.animal.h"
@@ -1038,6 +1039,19 @@ shared_ptr<MultiplayerLocalPlayer> Minecraft::createExtraLocalPlayer(int idx, co
 		PlayerUID playerXUIDOnline = INVALID_XUID;
 		ProfileManager.GetXUID(idx,&playerXUIDOffline,false);
 		ProfileManager.GetXUID(idx,&playerXUIDOnline,true);
+#ifdef _WINDOWS64
+		// Compatibility rule for Win64 id migration
+		// host keeps legacy host XUID, non-host uses persistent uid.dat XUID.
+		INetworkPlayer *localNetworkPlayer = g_NetworkManager.GetLocalPlayerByUserIndex(idx);
+		if(localNetworkPlayer != NULL && localNetworkPlayer->IsHost())
+		{
+			playerXUIDOffline = Win64Xuid::GetLegacyEmbeddedHostXuid();
+		}
+		else
+		{
+			playerXUIDOffline = Win64Xuid::ResolvePersistentXuid();
+		}
+#endif
 		localplayers[idx]->setXuid(playerXUIDOffline);
 		localplayers[idx]->setOnlineXuid(playerXUIDOnline);
 		localplayers[idx]->setIsGuest(ProfileManager.IsGuest(idx));
@@ -4298,6 +4312,19 @@ void Minecraft::setLevel(MultiPlayerLevel *level, int message /*=-1*/, shared_pt
 				// player doesn't have an online UID, set it from the player name
 				playerXUIDOnline.setForAdhoc();
 			}
+#endif
+#ifdef _WINDOWS64
+			// On Windows, the implementation has been changed to use a per-client pseudo XUID based on `uid.dat`.  
+			// To maintain player data compatibility with existing worlds, the world host (the first player) will use the previous embedded pseudo XUID.
+			INetworkPlayer *localNetworkPlayer = g_NetworkManager.GetLocalPlayerByUserIndex(iPrimaryPlayer);
+			if(localNetworkPlayer != NULL && localNetworkPlayer->IsHost())
+			{
+				playerXUIDOffline = Win64Xuid::GetLegacyEmbeddedHostXuid();
+			}
+			else
+			{
+				playerXUIDOffline = Win64Xuid::ResolvePersistentXuid();
+			}
 #endif
 			player->setXuid(playerXUIDOffline);
 			player->setOnlineXuid(playerXUIDOnline);
@@ -4481,6 +4508,18 @@ void Minecraft::respawnPlayer(int iPad, int dimension, int newEntityId)
 	PlayerUID playerXUIDOnline = INVALID_XUID;
 	ProfileManager.GetXUID(iTempPad,&playerXUIDOffline,false);
 	ProfileManager.GetXUID(iTempPad,&playerXUIDOnline,true);
+#ifdef _WINDOWS64
+	// Same compatibility rule as create/init paths.
+	INetworkPlayer *localNetworkPlayer = g_NetworkManager.GetLocalPlayerByUserIndex(iTempPad);
+	if(localNetworkPlayer != NULL && localNetworkPlayer->IsHost())
+	{
+		playerXUIDOffline = Win64Xuid::GetLegacyEmbeddedHostXuid();
+	}
+	else
+	{
+		playerXUIDOffline = Win64Xuid::ResolvePersistentXuid();
+	}
+#endif
 	player->setXuid(playerXUIDOffline);
 	player->setOnlineXuid(playerXUIDOnline);
 	player->setIsGuest( ProfileManager.IsGuest(iTempPad) );

Minecraft.Client/PendingConnection.cpp

@@ -161,6 +161,23 @@ void PendingConnection::handleLogin(shared_ptr<LoginPacket> packet)
 	//if (true)// 4J removed !server->onlineMode)
 	bool sentDisconnect = false;
 
+	// Use the same Xuid choice as handleAcceptedLogin (offline first, online fallback).
+	// 
+	PlayerUID loginXuid = packet->m_offlineXuid;
+	if (loginXuid == INVALID_XUID) loginXuid = packet->m_onlineXuid;
+
+	bool duplicateXuid = false;
+	if (loginXuid != INVALID_XUID && server->getPlayers()->getPlayer(loginXuid) != nullptr)
+	{
+		duplicateXuid = true;
+	}
+	else if (packet->m_onlineXuid != INVALID_XUID &&
+		packet->m_onlineXuid != loginXuid &&
+		server->getPlayers()->getPlayer(packet->m_onlineXuid) != nullptr)
+	{
+		duplicateXuid = true;
+	}
+
 	if( sentDisconnect )
 	{
 		// Do nothing
@@ -169,6 +186,12 @@ void PendingConnection::handleLogin(shared_ptr<LoginPacket> packet)
 	{
 		disconnect(DisconnectPacket::eDisconnect_Banned);
 	}
+	else if (duplicateXuid)
+	{
+		// if same XUID already in use by another player so disconnect this one.
+		app.DebugPrintf("Rejecting duplicate xuid for name: %ls\n", name.c_str());
+		disconnect(DisconnectPacket::eDisconnect_Banned);
+	}
 #ifdef _WINDOWS64
 	else if (g_bRejectDuplicateNames)
 	{

Minecraft.Client/PlayerList.cpp

@@ -18,6 +18,7 @@
 #include "..\Minecraft.World\ArrayWithLength.h"
 #include "..\Minecraft.World\net.minecraft.network.packet.h"
 #include "..\Minecraft.World\net.minecraft.network.h"
+#include "Windows64\Windows64_Xuid.h"
 #include "..\Minecraft.World\Pos.h"
 #include "..\Minecraft.World\ProgressListener.h"
 #include "..\Minecraft.World\HellRandomLevelSource.h"
@@ -106,11 +107,18 @@ void PlayerList::placeNewPlayer(Connection *connection, shared_ptr<ServerPlayer>
 	}
 #endif
 #ifdef _WINDOWS64
-	if (networkPlayer != NULL && !networkPlayer->IsLocal())
+	if (networkPlayer != NULL)
 	{
 		NetworkPlayerXbox* nxp = (NetworkPlayerXbox*)networkPlayer;
 		IQNetPlayer* qnp = nxp->GetQNetPlayer();
-		wcsncpy_s(qnp->m_gamertag, 32, player->name.c_str(), _TRUNCATE);
+		if (qnp != NULL)
+		{
+			if (!networkPlayer->IsLocal())
+			{
+				wcsncpy_s(qnp->m_gamertag, 32, player->name.c_str(), _TRUNCATE);
+			}
+			qnp->m_resolvedXuid = player->getXuid();
+		}
 	}
 #endif
 	// 4J Stu - TU-1 hotfix
@@ -520,12 +528,20 @@ shared_ptr<ServerPlayer> PlayerList::getPlayerForLogin(PendingConnection *pendin
 	player->setOnlineXuid( onlineXuid ); // 4J Added
 #ifdef _WINDOWS64
 	{
+		// Use packet-supplied identity from LoginPacket.
+		// Do not recompute from name here: mixed-version clients must stay compatible.
 		INetworkPlayer* np = pendingConnection->connection->getSocket()->getPlayer();
 		if (np != NULL)
 		{
-			PlayerUID realXuid = np->GetUID();
-			player->setXuid(realXuid);
-			player->setOnlineXuid(realXuid);
+			player->setOnlineXuid(np->GetUID());
+
+			// Backward compatibility: when Minecraft.Client is hosting, keep the first
+			// host player on the legacy embedded host XUID (base + 0).
+			// This preserves pre-migration host playerdata in existing worlds.
+			if (np->IsHost())
+			{
+				player->setXuid(Win64Xuid::GetLegacyEmbeddedHostXuid());
+			}
 		}
 	}
 #endif

Minecraft.Client/Windows64/Windows64_Minecraft.cpp

@@ -42,6 +42,7 @@
 #include "..\..\Minecraft.World\OldChunkStorage.h"
 #include "Common/PostProcesser.h"
 #include "Network\WinsockNetLayer.h"
+#include "Windows64_Xuid.h"
 
 #include "Xbox/resource.h"
 
@@ -110,6 +111,7 @@ struct Win64LaunchOptions
 {
 	int screenMode;
 	bool serverMode;
+	bool fullscreen;
 };
 
 static void CopyWideArgToAnsi(LPCWSTR source, char* dest, size_t destSize)
@@ -256,6 +258,8 @@ static Win64LaunchOptions ParseLaunchOptions()
 					g_Win64MultiplayerPort = (int)port;
 			}
 		}
+		else if (_wcsicmp(argv[i], L"-fullscreen") == 0)
+			options.fullscreen = true;
 	}
 
 	LocalFree(argv);
@@ -1218,6 +1222,12 @@ int APIENTRY _tWinMain(_In_ HINSTANCE hInstance,
 	Win64LaunchOptions launchOptions = ParseLaunchOptions();
 	ApplyScreenMode(launchOptions.screenMode);
 
+	// Ensure uid.dat exists from startup in client mode (before any multiplayer/login path).
+	if (!launchOptions.serverMode)
+	{
+		Win64Xuid::ResolvePersistentXuid();
+	}
+
 	// If no username, let's fall back
 	if (g_Win64Username[0] == 0)
 	{
@@ -1245,7 +1255,7 @@ int APIENTRY _tWinMain(_In_ HINSTANCE hInstance,
 	}
 
 	// Restore fullscreen state from previous session
-	if (LoadFullscreenOption() && !g_isFullscreen)
+	if (LoadFullscreenOption() && !g_isFullscreen || launchOptions.fullscreen)
 	{
 		ToggleFullscreen();
 	}

Minecraft.Client/Windows64/Windows64_Xuid.h

@@ -0,0 +1,214 @@
+#pragma once
+
+#ifdef _WINDOWS64
+
+#include <string>
+#include <cstdio>
+#include <cstdlib>
+#include <cerrno>
+#include <cstring>
+#include <Windows.h>
+
+namespace Win64Xuid
+{
+	inline PlayerUID GetLegacyEmbeddedBaseXuid()
+	{
+		return (PlayerUID)0xe000d45248242f2eULL;
+	}
+
+	inline PlayerUID GetLegacyEmbeddedHostXuid()
+	{
+		// Legacy behavior used "embedded base + smallId"; host was always smallId 0.
+		// We intentionally keep this value for host/self compatibility with pre-migration worlds.
+		return GetLegacyEmbeddedBaseXuid();
+	}
+
+	inline bool IsLegacyEmbeddedRange(PlayerUID xuid)
+	{
+		// Old Win64 XUIDs were not persistent and always lived in this narrow base+smallId range.
+		// Treat them as legacy/non-persistent so uid.dat values never collide with old slot IDs.
+		const PlayerUID base = GetLegacyEmbeddedBaseXuid();
+		return xuid >= base && xuid < (base + MINECRAFT_NET_MAX_PLAYERS);
+	}
+
+	inline bool IsPersistedUidValid(PlayerUID xuid)
+	{
+		return xuid != INVALID_XUID && !IsLegacyEmbeddedRange(xuid);
+	}
+
+
+	// ./uid.dat
+	inline bool BuildUidFilePath(char* outPath, size_t outPathSize)
+	{
+		if (outPath == NULL || outPathSize == 0)
+			return false;
+
+		outPath[0] = 0;
+
+		char exePath[MAX_PATH] = {};
+		DWORD len = GetModuleFileNameA(NULL, exePath, MAX_PATH);
+		if (len == 0 || len >= MAX_PATH)
+			return false;
+
+		char* lastSlash = strrchr(exePath, '\\');
+		if (lastSlash != NULL)
+		{
+			*(lastSlash + 1) = 0;
+		}
+
+		if (strcpy_s(outPath, outPathSize, exePath) != 0)
+			return false;
+		if (strcat_s(outPath, outPathSize, "uid.dat") != 0)
+			return false;
+
+		return true;
+	}
+
+	inline bool ReadUid(PlayerUID* outXuid)
+	{
+		if (outXuid == NULL)
+			return false;
+
+		char path[MAX_PATH] = {};
+		if (!BuildUidFilePath(path, MAX_PATH))
+			return false;
+
+		FILE* f = NULL;
+		if (fopen_s(&f, path, "rb") != 0 || f == NULL)
+			return false;
+
+		char buffer[128] = {};
+		size_t readBytes = fread(buffer, 1, sizeof(buffer) - 1, f);
+		fclose(f);
+
+		if (readBytes == 0)
+			return false;
+
+		// Compatibility: earlier experiments may have written raw 8-byte uid.dat.
+		if (readBytes == sizeof(unsigned __int64))
+		{
+			unsigned __int64 raw = 0;
+			memcpy(&raw, buffer, sizeof(raw));
+			PlayerUID parsed = (PlayerUID)raw;
+			if (IsPersistedUidValid(parsed))
+			{
+				*outXuid = parsed;
+				return true;
+			}
+		}
+
+		buffer[readBytes] = 0;
+		char* begin = buffer;
+		while (*begin == ' ' || *begin == '\t' || *begin == '\r' || *begin == '\n')
+		{
+			++begin;
+		}
+
+		errno = 0;
+		char* end = NULL;
+		unsigned __int64 raw = _strtoui64(begin, &end, 0);
+		if (begin == end || errno != 0)
+			return false;
+
+		while (*end == ' ' || *end == '\t' || *end == '\r' || *end == '\n')
+		{
+			++end;
+		}
+		if (*end != 0)
+			return false;
+
+		PlayerUID parsed = (PlayerUID)raw;
+		if (!IsPersistedUidValid(parsed))
+			return false;
+
+		*outXuid = parsed;
+		return true;
+	}
+
+	inline bool WriteUid(PlayerUID xuid)
+	{
+		char path[MAX_PATH] = {};
+		if (!BuildUidFilePath(path, MAX_PATH))
+			return false;
+
+		FILE* f = NULL;
+		if (fopen_s(&f, path, "wb") != 0 || f == NULL)
+			return false;
+
+		int written = fprintf_s(f, "0x%016llX\n", (unsigned long long)xuid);
+		fclose(f);
+		return written > 0;
+	}
+
+	inline unsigned __int64 Mix64(unsigned __int64 x)
+	{
+		x += 0x9E3779B97F4A7C15ULL;
+		x = (x ^ (x >> 30)) * 0xBF58476D1CE4E5B9ULL;
+		x = (x ^ (x >> 27)) * 0x94D049BB133111EBULL;
+		return x ^ (x >> 31);
+	}
+
+	inline PlayerUID GeneratePersistentUid()
+	{
+		// Avoid rand_s dependency: mix several Win64 runtime values into a 64-bit seed.
+		FILETIME ft = {};
+		GetSystemTimeAsFileTime(&ft);
+		unsigned __int64 t = (((unsigned __int64)ft.dwHighDateTime) << 32) | ft.dwLowDateTime;
+
+		LARGE_INTEGER qpc = {};
+		QueryPerformanceCounter(&qpc);
+
+		unsigned __int64 seed = t;
+		seed ^= (unsigned __int64)qpc.QuadPart;
+		seed ^= ((unsigned __int64)GetCurrentProcessId() << 32);
+		seed ^= (unsigned __int64)GetCurrentThreadId();
+		seed ^= (unsigned __int64)GetTickCount();
+		seed ^= (unsigned __int64)(size_t)&qpc;
+		seed ^= (unsigned __int64)(size_t)GetModuleHandleA(NULL);
+
+		unsigned __int64 raw = Mix64(seed) ^ Mix64(seed + 0xA0761D6478BD642FULL);
+		raw ^= 0x8F4B2D6C1A93E705ULL;
+		raw |= 0x8000000000000000ULL;
+
+		PlayerUID xuid = (PlayerUID)raw;
+		if (!IsPersistedUidValid(xuid))
+		{
+			raw ^= 0x0100000000000001ULL;
+			xuid = (PlayerUID)raw;
+		}
+
+		if (!IsPersistedUidValid(xuid))
+		{
+			// Last-resort deterministic fallback for pathological cases.
+			xuid = (PlayerUID)0xD15EA5E000000001ULL;
+		}
+
+		return xuid;
+	}
+
+	inline PlayerUID ResolvePersistentXuid()
+	{
+		// Process-local cache: uid.dat is immutable during runtime and this path is hot.
+		static bool s_cached = false;
+		static PlayerUID s_xuid = INVALID_XUID;
+
+		if (s_cached)
+			return s_xuid;
+
+		PlayerUID fileXuid = INVALID_XUID;
+		if (ReadUid(&fileXuid))
+		{
+			s_xuid = fileXuid;
+			s_cached = true;
+			return s_xuid;
+		}
+
+		// First launch on this client: generate once and persist to uid.dat.
+		s_xuid = GeneratePersistentUid();
+		WriteUid(s_xuid);
+		s_cached = true;
+		return s_xuid;
+	}
+}
+
+#endif

Minecraft.World/Boat.cpp

@@ -74,7 +74,7 @@ bool Boat::isPushable()
 Boat::Boat(Level *level, double x, double y, double z) : Entity( level )
 {
 	_init();
-	setPos(x, y + heightOffset, z);
+	setPos(x, y + heightOffset + 0.1, z);
 
 	xd = 0;
 	yd = 0;
@@ -209,30 +209,9 @@ void Boat::tick()
 	}
 
 	double lastSpeed = sqrt(xd * xd + zd * zd);
-	if (lastSpeed > MAX_COLLISION_SPEED)
+	if (lastSpeed > MAX_COLLISION_SPEED && waterPercentage > 1)
 	{
-		double xa = cos(yRot * PI / 180);
-		double za = sin(yRot * PI / 180);
-
-		for (int i = 0; i < 1 + lastSpeed * 60; i++)
-		{
-
-			double side = (random->nextFloat() * 2 - 1);
-
-			double side2 = (random->nextInt(2) * 2 - 1) * 0.7;
-			if (random->nextBoolean())
-			{
-				double xx = x - xa * side * 0.8 + za * side2;
-				double zz = z - za * side * 0.8 - xa * side2;
-				level->addParticle(eParticleType_splash, xx, y - 2 / 16.0f, zz, +xd, yd, +zd);
-			}
-			else
-			{
-				double xx = x + xa + za * side * 0.7;
-				double zz = z + za - xa * side * 0.7;
-				level->addParticle(eParticleType_splash, xx, y - 2 / 16.0f, zz, +xd, yd, +zd);
-			}
-		}
+		createSplash(lastSpeed);
 	}
 
 	if (level->isClientSide && doLerp)
@@ -254,7 +233,6 @@ void Boat::tick()
 		}
 		else
 		{
-#if 1
 			// Original
 			//double xt = x + xd;
 			//double yt = y + yd;
@@ -273,51 +251,23 @@ void Boat::tick()
 			xd *= 0.99f;
 			yd *= 0.95f;
 			zd *= 0.99f;
-#else
-			// 4J Stu - Fix for #8280 - Gameplay : Boats behave erratically when exited next to land.
-			// The client shouldn't change the position of the boat
-			double xt = x;// + xd;
-			double yt = y + yd;
-			double zt = z;// + zd;
-			this->setPos(xt, yt, zt);
-
-			// 4J Stu - Fix for #9579 - GAMEPLAY: Boats with a player in them slowly sink under the water over time, and with no player in them they float into the sky.
-			// Just make the boats bob up and down rather than any other client-side movement when not receiving packets from server
-	        if (waterPercentage > 0)
-	        {
-		        double bob = waterPercentage * 2 - 1;
-		        yd += 0.04f * bob;
-	        }
-			else
-			{
-				if (yd < 0) yd /= 2;
-				yd += 0.007f;
-			}
-			//if (onGround)
-			//{
-			xd *= 0.5f;
-			yd *= 0.5f;
-			zd *= 0.5f;
-			//}
-			//xd *= 0.99f;
-			//yd *= 0.95f;
-			//zd *= 0.99f;
-#endif
 		}
 		return;
 	}
 
+	// Bob on water
 	if (waterPercentage > 0)
 	{
 		double bob = waterPercentage * 2 - 1;
 		yd += 0.04f * bob;
 	}
-	else
-	{
-		yd = 0;
+	
+	// Reimplement "gravity"
+	if (level->getTile(x, Mth::floor(y - 0.15), z) == 0 && !onGround) {
+		yd += 0.04f * -1.0; // -1.0 is what bob should return in this situation, just hardcoded.
 	}
 
-
+	// Rider Controls
 	if ( rider.lock() != NULL && rider.lock()->instanceof(eTYPE_LIVINGENTITY) )
 	{
 		shared_ptr<LivingEntity> livingRider = dynamic_pointer_cast<LivingEntity>(rider.lock());
@@ -334,6 +284,7 @@ void Boat::tick()
 
 	double curSpeed = sqrt(xd * xd + zd * zd);
 
+	// Speed Clamp
 	if (curSpeed > MAX_SPEED)
 	{
 		double ratio = MAX_SPEED / curSpeed;
@@ -354,14 +305,15 @@ void Boat::tick()
 		if (acceleration < MIN_ACCELERATION) acceleration = MIN_ACCELERATION;
 	}
 
+	// Slow speed on ground
 	if (onGround)
 	{
 		xd *= 0.5f;
-		yd *= 0.5f;
 		zd *= 0.5f;
 	}
 	move(xd, yd, zd);
 
+	// Break boat 
 	if ((horizontalCollision && lastSpeed > 0.20))
 	{
 		if (!level->isClientSide && !removed)
@@ -401,6 +353,7 @@ void Boat::tick()
 	yRot += (float) rotDiff;
 	setRot(yRot, xRot);
 
+	// Server only code below
 	if(level->isClientSide) return;
 
 	vector<shared_ptr<Entity> > *entities = level->getEntities(shared_from_this(), bb->grow(0.2f, 0, 0.2f));
@@ -444,13 +397,37 @@ void Boat::tick()
 	}
 }
 
+void Boat::createSplash(double particleStrengh) {
+	double xa = cos(yRot * PI / 180);
+	double za = sin(yRot * PI / 180);
+
+	for (int i = 0; i < 1 + particleStrengh * 60; i++)
+	{
+		double side = (random->nextFloat() * 2 - 1);
+
+		double side2 = (random->nextInt(2) * 2 - 1) * 0.7;
+		if (random->nextBoolean())
+		{
+			double xx = x - xa * side * 0.8 + za * side2;
+			double zz = z - za * side * 0.8 - xa * side2;
+			level->addParticle(eParticleType_splash, xx, y - 2 / 16.0f, zz, +xd, yd, +zd);
+		}
+		else
+		{
+			double xx = x + xa + za * side * 0.7;
+			double zz = z + za - xa * side * 0.7;
+			level->addParticle(eParticleType_splash, xx, y - 2 / 16.0f, zz, +xd, yd, +zd);
+		}
+	}
+}
+
 void Boat::positionRider()
 {
 	if (rider.lock() == NULL) return;
 
 	double xa = cos(yRot * PI / 180) * 0.4;
 	double za = sin(yRot * PI / 180) * 0.4;
-	rider.lock()->setPos(x + xa, y + getRideHeight() + rider.lock()->getRidingHeight(), z + za);
+	rider.lock()->setPos(x + xa, y + getRideHeight() + rider.lock()->getRidingHeight()-0.5, z + za);
 }
 
 

Minecraft.World/Boat.h

@@ -60,6 +60,7 @@ public:
 	virtual void lerpTo(double x, double y, double z, float yRot, float xRot, int steps);
 	virtual void lerpMotion(double xd, double yd, double zd);
 	virtual void tick();
+	void createSplash(double particleStrengh);
 	virtual void positionRider();
 
 protected:

Minecraft.World/x64headers/extraX64.h

@@ -219,6 +219,7 @@ public:
     BYTE m_smallId;
     bool m_isRemote;
     bool m_isHostPlayer;
+    PlayerUID m_resolvedXuid;
     wchar_t m_gamertag[32];
 private:
 	ULONG_PTR m_customData;