From 48370d74b7093c67cf8f45b4af4a7bee55e9f355 Mon Sep 17 00:00:00 2001
From: quake1337 <3310937+bartico6@users.noreply.github.com>
Date: Tue, 13 Jul 2021 21:33:35 +0200
Subject: [PATCH] Missing group safeguards.

- Server will no longer start up when the guest or default groups cannot
  be located.
- Players joining with unknown groups assigned to them will be
  disconnected with an error
---
 TShockAPI/Commands.cs        |  7 +++++--
 TShockAPI/DB/GroupManager.cs | 15 +++++++++++++++
 TShockAPI/GetDataHandlers.cs | 10 ++++++++--
 TShockAPI/TShock.cs          |  1 +
 TShockAPI/Utils.cs           | 11 +++++++++++
 TerrariaServerAPI            |  2 +-
 6 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/TShockAPI/Commands.cs b/TShockAPI/Commands.cs
index b6ba179f..80e710ad 100644
--- a/TShockAPI/Commands.cs
+++ b/TShockAPI/Commands.cs
@@ -823,10 +823,13 @@ namespace TShockAPI
 						(usingUUID && account.UUID == args.Player.UUID && !TShock.Config.Settings.DisableUUIDLogin &&
 						!String.IsNullOrWhiteSpace(args.Player.UUID)))
 				{
-					args.Player.PlayerData = TShock.CharacterDB.GetPlayerData(args.Player, account.ID);
-
 					var group = TShock.Groups.GetGroupByName(account.Group);
 
+					if (!TShock.Utils.AssertGroupValid(args.Player, group))
+						return;
+
+					args.Player.PlayerData = TShock.CharacterDB.GetPlayerData(args.Player, account.ID);
+
 					args.Player.Group = group;
 					args.Player.tempGroup = null;
 					args.Player.Account = account;
diff --git a/TShockAPI/DB/GroupManager.cs b/TShockAPI/DB/GroupManager.cs
index 7b3b62dd..8133edaa 100644
--- a/TShockAPI/DB/GroupManager.cs
+++ b/TShockAPI/DB/GroupManager.cs
@@ -202,6 +202,21 @@ namespace TShockAPI.DB
 			Group.DefaultGroup = GetGroupByName(TShock.Config.Settings.DefaultGuestGroupName);
 		}
 
+		internal void EnsureCoreGroupsPresent()
+		{
+			if (!GroupExists(TShock.Config.Settings.DefaultGuestGroupName))
+			{
+				TShock.Log.ConsoleError("The guest group could not be found. This may indicate a typo in the configuration file, or that the group was renamed or deleted.");
+				throw new Exception("The guest group could not be found.");
+			}
+
+			if(!GroupExists(TShock.Config.Settings.DefaultRegistrationGroupName))
+            {
+				TShock.Log.ConsoleError("The default usergroup could not be found. This may indicate a typo in the configuration file, or that the group was renamed or deleted.");
+				throw new Exception("The default usergroup could not be found.");
+            }
+		}
+
 		private void AddDefaultGroup(string name, string parent, string permissions)
 		{
 			if (!GroupExists(name))
diff --git a/TShockAPI/GetDataHandlers.cs b/TShockAPI/GetDataHandlers.cs
index e92d19a9..b90f6fe1 100644
--- a/TShockAPI/GetDataHandlers.cs
+++ b/TShockAPI/GetDataHandlers.cs
@@ -2450,10 +2450,13 @@ namespace TShockAPI
 						args.Player.State = 2;
 					NetMessage.SendData((int)PacketTypes.WorldInfo, args.Player.Index);
 
-					args.Player.PlayerData = TShock.CharacterDB.GetPlayerData(args.Player, account.ID);
-
 					var group = TShock.Groups.GetGroupByName(account.Group);
 
+					if (!TShock.Utils.AssertGroupValid(args.Player, group))
+						return true;
+
+					args.Player.PlayerData = TShock.CharacterDB.GetPlayerData(args.Player, account.ID);
+
 					args.Player.Group = group;
 					args.Player.tempGroup = null;
 					args.Player.Account = account;
@@ -3004,6 +3007,9 @@ namespace TShockAPI
 
 					var group = TShock.Groups.GetGroupByName(account.Group);
 
+					if (!TShock.Utils.AssertGroupValid(args.Player, group))
+						return true;
+
 					args.Player.Group = group;
 					args.Player.tempGroup = null;
 					args.Player.Account = account;
diff --git a/TShockAPI/TShock.cs b/TShockAPI/TShock.cs
index ed74b882..bc1d26e7 100644
--- a/TShockAPI/TShock.cs
+++ b/TShockAPI/TShock.cs
@@ -322,6 +322,7 @@ namespace TShockAPI
 				Regions = new RegionManager(DB);
 				UserAccounts = new UserAccountManager(DB);
 				Groups = new GroupManager(DB);
+				Groups.EnsureCoreGroupsPresent();
 				ProjectileBans = new ProjectileManagager(DB);
 				TileBans = new TileManager(DB);
 				RememberedPos = new RememberedPosManager(DB);
diff --git a/TShockAPI/Utils.cs b/TShockAPI/Utils.cs
index 23007b19..36a6d348 100644
--- a/TShockAPI/Utils.cs
+++ b/TShockAPI/Utils.cs
@@ -212,6 +212,17 @@ namespace TShockAPI
 			} while (TilePlacementValid(tileX, tileY) && TileSolid(tileX, tileY));
 		}
 
+		public bool AssertGroupValid(TSPlayer player, Group group)
+        {
+			if (group == null)
+			{
+				player.Disconnect("Your account's group could not be found. Please contact server administrators about this.");
+				return false;
+			}
+
+			return true;
+		}
+
 		/// <summary>
 		/// Determines if a tile is valid.
 		/// </summary>
diff --git a/TerrariaServerAPI b/TerrariaServerAPI
index 8c2c0873..4b555bc3 160000
--- a/TerrariaServerAPI
+++ b/TerrariaServerAPI
@@ -1 +1 @@
-Subproject commit 8c2c087327bbd1f20ff6c46f4d11e5714e57064b
+Subproject commit 4b555bc373dbb470bc69ebed69c79de116f28df2