Increase SyncInfo packet size limits

mibac138 · mibac138 · commit 79da5f8cae4d · 2025-10-10T01:51:41.000+02:00
diff --git a/Source/Client/ConstantTicker.cs b/Source/Client/ConstantTicker.cs
@@ -1,3 +1,4 @@
+using System;
 using HarmonyLib;
 using Multiplayer.Client.Desyncs;
 using Multiplayer.Common;
@@ -80,10 +81,19 @@ private static void TickSyncCoordinator()
             {
                 sync.currentOpinion.roundMode = RoundMode.GetCurrentRoundMode();
 
-                if (!TickPatch.Simulating && (Multiplayer.LocalServer != null || Multiplayer.arbiterInstance))
-                    Multiplayer.Client.SendFragmented(new ClientSyncInfoPacket
-                        { SyncOpinion = sync.currentOpinion.ToNet() }.Serialize());
-
+                try
+                {
+                    // In case sending the opinion failed, just keep on going and ignore it. We need to make sure that
+                    // sync.currentOpinion is set to null to prevent cascading failure where the opinion keeps getting
+                    // bigger and the sending keeps failing because of a too big packet.
+                    if (!TickPatch.Simulating && (Multiplayer.LocalServer != null || Multiplayer.arbiterInstance))
+                        Multiplayer.Client.SendFragmented(new ClientSyncInfoPacket
+                            { SyncOpinion = sync.currentOpinion.ToNet() }.Serialize());
+                }
+                catch (Exception e)
+                {
+                    Log.Error($"Failed to send client sync info packet {e}");
+                }
                 sync.AddClientOpinionAndCheckDesync(sync.currentOpinion);
                 sync.currentOpinion = null;
             }
diff --git a/Source/Common/Networking/Packet/IPacket.cs b/Source/Common/Networking/Packet/IPacket.cs
@@ -179,7 +179,7 @@ public override void BindBytes(ref byte[] obj, int maxLength = DefaultMaxLength)
     public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = DefaultMaxLength)
     {
         int len = reader.ReadInt32();
-        if (len > maxLength && maxLength != -1) throw new ReaderException("Object too big");
+        if (len > maxLength && maxLength != -1) throw new ReaderException($"Array too big ({len}>{maxLength})");
 
         obj = new T[len];
         for (var i = 0; i < len; i++)
@@ -192,14 +192,14 @@ public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = Defaul
 
     public override void BindRemaining(ref byte[] obj, int maxLength = DefaultMaxLength)
     {
-        if (reader.Left > maxLength) throw new ReaderException("Object too big");
+        if (reader.Left > maxLength) throw new ReaderException($"Remaining bytes too big ({reader.Left}>{maxLength})");
         obj = reader.ReadRaw(reader.Left);
     }
 
     public override void Bind<T>(ref List<T> obj, Binder<T> bind, int maxLength = DefaultMaxLength)
     {
         int len = reader.ReadInt32();
-        if (len > maxLength) throw new ReaderException("Object too big");
+        if (len > maxLength) throw new ReaderException($"List too big ({len}>{maxLength})");
 
         obj = new List<T>(len);
         for (var i = 0; i < len; i++)
@@ -214,7 +214,7 @@ public override void Bind<K, V>(ref Dictionary<K, V> obj, Binder<K> bindKey, Bin
         int maxLength = DefaultMaxLength)
     {
         int len = reader.ReadInt32();
-        if (len > maxLength && maxLength != -1) throw new ReaderException("Object too big");
+        if (len > maxLength && maxLength != -1) throw new ReaderException($"Dictionary too big ({len}>{maxLength})");
 
         obj = new Dictionary<K, V>(len);
         for (int i = 0; i < len; i++)
@@ -260,7 +260,7 @@ public sealed class PacketWriter(ByteWriter writer) : PacketBuffer(true)
 
     public override void Bind(ref string obj, int maxLength = DefaultMaxLength)
     {
-        if (obj != null && obj.Length > maxLength) throw new WriterException("Too long string");
+        if (obj != null && obj.Length > maxLength) throw new WriterException($"Too long string ({obj.Length}>{maxLength})");
         writer.WriteString(obj);
     }
 
@@ -274,7 +274,7 @@ public override void BindBytes(ref byte[] obj, int maxLength = DefaultMaxLength)
 
     public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = DefaultMaxLength)
     {
-        if (obj.Length > maxLength) throw new WriterException("Object too big");
+        if (obj.Length > maxLength) throw new WriterException($"Array too big ({obj.Length}>{maxLength})");
         writer.WriteInt32(obj.Length);
         for (var i = 0; i < obj.Length; i++)
         {
@@ -284,13 +284,13 @@ public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = Defaul
 
     public override void BindRemaining(ref byte[] obj, int maxLength = DefaultMaxLength)
     {
-        if (obj.Length > maxLength) throw new WriterException("Object too big");
+        if (obj.Length > maxLength) throw new WriterException($"Remaining bytes too big ({obj.Length}>{maxLength})");
         writer.WriteRaw(obj);
     }
 
     public override void Bind<T>(ref List<T> obj, Binder<T> bind, int maxLength = DefaultMaxLength)
     {
-        if (obj.Count > maxLength) throw new WriterException("Object too big");
+        if (obj.Count > maxLength) throw new WriterException($"List too big ({obj.Count}>{maxLength})");
         writer.WriteInt32(obj.Count);
         for (var i = 0; i < obj.Count; i++)
         {
@@ -302,7 +302,7 @@ public override void Bind<T>(ref List<T> obj, Binder<T> bind, int maxLength = De
     public override void Bind<K, V>(ref Dictionary<K, V> obj, Binder<K> bindKey, Binder<V> bindValue,
         int maxLength = DefaultMaxLength)
     {
-        if (obj.Count > maxLength) throw new WriterException("Object too big");
+        if (obj.Count > maxLength) throw new WriterException($"Dictionary too big ({obj.Count}>{maxLength})");
         writer.WriteInt32(obj.Count);
         foreach (var (key, value) in obj)
         {
diff --git a/Source/Common/Networking/Packet/SyncInfoPacket.cs b/Source/Common/Networking/Packet/SyncInfoPacket.cs
@@ -5,6 +5,8 @@ namespace Multiplayer.Common.Networking.Packet;
 [PacketDefinition(Packets.Client_SyncInfo, allowFragmented: true)]
 public record struct ClientSyncInfoPacket : IPacket
 {
+    // 1MiB. For some big saves, the sync opinion can reach ~650KiB, so this includes some leeway.
+    public const int MaxLength = 1 << 20;
     public byte[] rawSyncOpinion;
 
     public SyncOpinion SyncOpinion
@@ -15,7 +17,7 @@ public SyncOpinion SyncOpinion
 
     public void Bind(PacketBuffer buf)
     {
-        buf.BindRemaining(ref rawSyncOpinion);
+        buf.BindRemaining(ref rawSyncOpinion, maxLength: MaxLength);
     }
 
     private static readonly Binder<SyncOpinion> SyncOpinionBinder = BinderOf.Identity<SyncOpinion>();
@@ -33,7 +35,7 @@ public SyncOpinion SyncOpinion
 
     public void Bind(PacketBuffer buf)
     {
-        buf.BindRemaining(ref rawSyncOpinion);
+        buf.BindRemaining(ref rawSyncOpinion, maxLength: ClientSyncInfoPacket.MaxLength);
     }
 
     private static readonly Binder<SyncOpinion> SyncOpinionBinder = BinderOf.Identity<SyncOpinion>();
@@ -56,7 +58,9 @@ public void Bind(PacketBuffer buf)
         buf.Bind(ref commandRandomStates, BinderOf.UInt());
         buf.Bind(ref worldRandomStates, BinderOf.UInt());
         buf.Bind(ref mapRandomStates, BinderOf.Identity<MapRandomState>());
-        buf.Bind(ref traceHashes, BinderOf.Int());
+        // Max 262k (256Ki) trace hashes. For some big saves, the trace hashes can reach ~60k entries, so this includes
+        // some leeway.
+        buf.Bind(ref traceHashes, BinderOf.Int(), maxLength: 1<<18);
 
         buf.Bind(ref simulating);
         buf.BindEnum(ref roundMode);
diff --git a/Source/Tests/packet-serializations/ClientSyncInfoPacket.verified.txt b/Source/Tests/packet-serializations/ClientSyncInfoPacket.verified.txt
@@ -1 +1 @@
-﻿39-30-00-00-03-00-00-00-01-00-00-00-02-00-00-00-03-00-00-00-03-00-00-00-0A-00-00-00-14-00-00-00-1E-00-00-00-02-00-00-00-01-00-00-00-02-00-00-00-6F-00-00-00-DE-00-00-00-02-00-00-00-03-00-00-00-4D-01-00-00-BC-01-00-00-2B-02-00-00-03-00-00-00-E7-03-00-00-78-03-00-00-09-03-00-00-01-00-00
+﻿39-30-00-00-03-00-00-00-01-00-00-00-02-00-00-00-03-00-00-00-03-00-00-00-0A-00-00-00-14-00-00-00-1E-00-00-00-02-00-00-00-01-00-00-00-02-00-00-00-6F-00-00-00-DE-00-00-00-02-00-00-00-03-00-00-00-4D-01-00-00-BC-01-00-00-2B-02-00-00-03-00-00-00-E7-03-00-00-78-03-00-00-09-03-00-00-01-00-00 (95 bytes)
diff --git a/Source/Tests/packet-serializations/ServerSyncInfoPacket.verified.txt b/Source/Tests/packet-serializations/ServerSyncInfoPacket.verified.txt
@@ -1 +1 @@
-﻿39-30-00-00-03-00-00-00-01-00-00-00-02-00-00-00-03-00-00-00-03-00-00-00-0A-00-00-00-14-00-00-00-1E-00-00-00-02-00-00-00-01-00-00-00-02-00-00-00-6F-00-00-00-DE-00-00-00-02-00-00-00-03-00-00-00-4D-01-00-00-BC-01-00-00-2B-02-00-00-03-00-00-00-E7-03-00-00-78-03-00-00-09-03-00-00-01-00-00
+﻿39-30-00-00-03-00-00-00-01-00-00-00-02-00-00-00-03-00-00-00-03-00-00-00-0A-00-00-00-14-00-00-00-1E-00-00-00-02-00-00-00-01-00-00-00-02-00-00-00-6F-00-00-00-DE-00-00-00-02-00-00-00-03-00-00-00-4D-01-00-00-BC-01-00-00-2B-02-00-00-03-00-00-00-E7-03-00-00-78-03-00-00-09-03-00-00-01-00-00 (95 bytes)

Original file line number	Diff line number	Diff line change
`@@ -179,7 +179,7 @@ public override void BindBytes(ref byte[] obj, int maxLength = DefaultMaxLength)`
`179`	`179`	`public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = DefaultMaxLength)`
`180`	`180`	`{`
`181`	`181`	`int len = reader.ReadInt32();`
`182`		`- if (len > maxLength && maxLength != -1) throw new ReaderException("Object too big");`
	`182`	`+ if (len > maxLength && maxLength != -1) throw new ReaderException($"Array too big ({len}>{maxLength})");`
`183`	`183`
`184`	`184`	`obj = new T[len];`
`185`	`185`	`for (var i = 0; i < len; i++)`
`@@ -192,14 +192,14 @@ public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = Defaul`
`192`	`192`
`193`	`193`	`public override void BindRemaining(ref byte[] obj, int maxLength = DefaultMaxLength)`
`194`	`194`	`{`
`195`		`- if (reader.Left > maxLength) throw new ReaderException("Object too big");`
	`195`	`+ if (reader.Left > maxLength) throw new ReaderException($"Remaining bytes too big ({reader.Left}>{maxLength})");`
`196`	`196`	`obj = reader.ReadRaw(reader.Left);`
`197`	`197`	`}`
`198`	`198`
`199`	`199`	`public override void Bind<T>(ref List<T> obj, Binder<T> bind, int maxLength = DefaultMaxLength)`
`200`	`200`	`{`
`201`	`201`	`int len = reader.ReadInt32();`
`202`		`- if (len > maxLength) throw new ReaderException("Object too big");`
	`202`	`+ if (len > maxLength) throw new ReaderException($"List too big ({len}>{maxLength})");`
`203`	`203`
`204`	`204`	`obj = new List<T>(len);`
`205`	`205`	`for (var i = 0; i < len; i++)`
`@@ -214,7 +214,7 @@ public override void Bind<K, V>(ref Dictionary<K, V> obj, Binder<K> bindKey, Bin`
`214`	`214`	`int maxLength = DefaultMaxLength)`
`215`	`215`	`{`
`216`	`216`	`int len = reader.ReadInt32();`
`217`		`- if (len > maxLength && maxLength != -1) throw new ReaderException("Object too big");`
	`217`	`+ if (len > maxLength && maxLength != -1) throw new ReaderException($"Dictionary too big ({len}>{maxLength})");`
`218`	`218`
`219`	`219`	`obj = new Dictionary<K, V>(len);`
`220`	`220`	`for (int i = 0; i < len; i++)`
`@@ -260,7 +260,7 @@ public sealed class PacketWriter(ByteWriter writer) : PacketBuffer(true)`
`260`	`260`
`261`	`261`	`public override void Bind(ref string obj, int maxLength = DefaultMaxLength)`
`262`	`262`	`{`
`263`		`- if (obj != null && obj.Length > maxLength) throw new WriterException("Too long string");`
	`263`	`+ if (obj != null && obj.Length > maxLength) throw new WriterException($"Too long string ({obj.Length}>{maxLength})");`
`264`	`264`	`writer.WriteString(obj);`
`265`	`265`	`}`
`266`	`266`
`@@ -274,7 +274,7 @@ public override void BindBytes(ref byte[] obj, int maxLength = DefaultMaxLength)`
`274`	`274`
`275`	`275`	`public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = DefaultMaxLength)`
`276`	`276`	`{`
`277`		`- if (obj.Length > maxLength) throw new WriterException("Object too big");`
	`277`	`+ if (obj.Length > maxLength) throw new WriterException($"Array too big ({obj.Length}>{maxLength})");`
`278`	`278`	`writer.WriteInt32(obj.Length);`
`279`	`279`	`for (var i = 0; i < obj.Length; i++)`
`280`	`280`	`{`
`@@ -284,13 +284,13 @@ public override void Bind<T>(ref T[] obj, Binder<T> bind, int maxLength = Defaul`
`284`	`284`
`285`	`285`	`public override void BindRemaining(ref byte[] obj, int maxLength = DefaultMaxLength)`
`286`	`286`	`{`
`287`		`- if (obj.Length > maxLength) throw new WriterException("Object too big");`
	`287`	`+ if (obj.Length > maxLength) throw new WriterException($"Remaining bytes too big ({obj.Length}>{maxLength})");`
`288`	`288`	`writer.WriteRaw(obj);`
`289`	`289`	`}`
`290`	`290`
`291`	`291`	`public override void Bind<T>(ref List<T> obj, Binder<T> bind, int maxLength = DefaultMaxLength)`
`292`	`292`	`{`
`293`		`- if (obj.Count > maxLength) throw new WriterException("Object too big");`
	`293`	`+ if (obj.Count > maxLength) throw new WriterException($"List too big ({obj.Count}>{maxLength})");`
`294`	`294`	`writer.WriteInt32(obj.Count);`
`295`	`295`	`for (var i = 0; i < obj.Count; i++)`
`296`	`296`	`{`
`@@ -302,7 +302,7 @@ public override void Bind<T>(ref List<T> obj, Binder<T> bind, int maxLength = De`
`302`	`302`	`public override void Bind<K, V>(ref Dictionary<K, V> obj, Binder<K> bindKey, Binder<V> bindValue,`
`303`	`303`	`int maxLength = DefaultMaxLength)`
`304`	`304`	`{`
`305`		`- if (obj.Count > maxLength) throw new WriterException("Object too big");`
	`305`	`+ if (obj.Count > maxLength) throw new WriterException($"Dictionary too big ({obj.Count}>{maxLength})");`
`306`	`306`	`writer.WriteInt32(obj.Count);`
`307`	`307`	`foreach (var (key, value) in obj)`
`308`	`308`	`{`
Original file line number	Diff line number	Diff line change
`@@ -5,6 +5,8 @@ namespace Multiplayer.Common.Networking.Packet;`
`5`	`5`	`[PacketDefinition(Packets.Client_SyncInfo, allowFragmented: true)]`
`6`	`6`	`public record struct ClientSyncInfoPacket : IPacket`
`7`	`7`	`{`
	`8`	`+ // 1MiB. For some big saves, the sync opinion can reach ~650KiB, so this includes some leeway.`
	`9`	`+ public const int MaxLength = 1 << 20;`
`8`	`10`	`public byte[] rawSyncOpinion;`
`9`	`11`
`10`	`12`	`public SyncOpinion SyncOpinion`
`@@ -15,7 +17,7 @@ public SyncOpinion SyncOpinion`
`15`	`17`
`16`	`18`	`public void Bind(PacketBuffer buf)`
`17`	`19`	`{`
`18`		`- buf.BindRemaining(ref rawSyncOpinion);`
	`20`	`+ buf.BindRemaining(ref rawSyncOpinion, maxLength: MaxLength);`
`19`	`21`	`}`
`20`	`22`
`21`	`23`	`private static readonly Binder<SyncOpinion> SyncOpinionBinder = BinderOf.Identity<SyncOpinion>();`
`@@ -33,7 +35,7 @@ public SyncOpinion SyncOpinion`
`33`	`35`
`34`	`36`	`public void Bind(PacketBuffer buf)`
`35`	`37`	`{`
`36`		`- buf.BindRemaining(ref rawSyncOpinion);`
	`38`	`+ buf.BindRemaining(ref rawSyncOpinion, maxLength: ClientSyncInfoPacket.MaxLength);`
`37`	`39`	`}`
`38`	`40`
`39`	`41`	`private static readonly Binder<SyncOpinion> SyncOpinionBinder = BinderOf.Identity<SyncOpinion>();`
`@@ -56,7 +58,9 @@ public void Bind(PacketBuffer buf)`
`56`	`58`	`buf.Bind(ref commandRandomStates, BinderOf.UInt());`
`57`	`59`	`buf.Bind(ref worldRandomStates, BinderOf.UInt());`
`58`	`60`	`buf.Bind(ref mapRandomStates, BinderOf.Identity<MapRandomState>());`
`59`		`- buf.Bind(ref traceHashes, BinderOf.Int());`
	`61`	`+ // Max 262k (256Ki) trace hashes. For some big saves, the trace hashes can reach ~60k entries, so this includes`
	`62`	`+ // some leeway.`
	`63`	`+ buf.Bind(ref traceHashes, BinderOf.Int(), maxLength: 1<<18);`
`60`	`64`
`61`	`65`	`buf.Bind(ref simulating);`
`62`	`66`	`buf.BindEnum(ref roundMode);`
Original file line number	Diff line number	Diff line change
`@@ -1 +1 @@`
`1`		`-39-30-00-00-03-00-00-00-01-00-00-00-02-00-00-00-03-00-00-00-03-00-00-00-0A-00-00-00-14-00-00-00-1E-00-00-00-02-00-00-00-01-00-00-00-02-00-00-00-6F-00-00-00-DE-00-00-00-02-00-00-00-03-00-00-00-4D-01-00-00-BC-01-00-00-2B-02-00-00-03-00-00-00-E7-03-00-00-78-03-00-00-09-03-00-00-01-00-00`
	`1`	`+39-30-00-00-03-00-00-00-01-00-00-00-02-00-00-00-03-00-00-00-03-00-00-00-0A-00-00-00-14-00-00-00-1E-00-00-00-02-00-00-00-01-00-00-00-02-00-00-00-6F-00-00-00-DE-00-00-00-02-00-00-00-03-00-00-00-4D-01-00-00-BC-01-00-00-2B-02-00-00-03-00-00-00-E7-03-00-00-78-03-00-00-09-03-00-00-01-00-00 (95 bytes)`