migrated pre-hard-fork patch 0011-do-not-break-message-chain-if-proxy…

…-cancels-a-chat-m.patch

cheetah-server/minecraft-patches/sources/net/minecraft/server/network/ServerGamePacketListenerImpl.java.patch

@@ -1,5 +1,68 @@
 --- a/net/minecraft/server/network/ServerGamePacketListenerImpl.java
 +++ b/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+@@ -2130,12 +_,23 @@
+     }
+
+     @Override
+-    public void handleChat(ServerboundChatPacket packet) {
++    public void handleChat(ServerboundChatPacket originalPacket) {
+         // CraftBukkit start - async chat
+         // SPIGOT-3638
+         if (this.server.isStopped()) {
+             return;
+         }
++        // Cheetah start - Do not break message chain if proxy cancels a chat message
++        boolean cancelled = originalPacket.lastSeenMessages().offset() < 0; // Canceling the signed chat packet on bungeecord side will break the chat chain on spigot side. Thus, the server will no longer be able to validate subsequent chat messages.
++        // We implement a little hack here: If the offset in the lastSeenMessages field is negative, the message will be correctly validated and the chat chain will be updated
++        // but the server will ignore the chat message, i.e. no events are called, it is not logged, and no player will see the message
++        final ServerboundChatPacket packet;
++        if (cancelled)  {
++            packet = new ServerboundChatPacket(originalPacket.message(), originalPacket.timeStamp(), originalPacket.salt(), originalPacket.signature(), new LastSeenMessages.Update(originalPacket.lastSeenMessages().offset() == Integer.MIN_VALUE ? 0 : -originalPacket.lastSeenMessages().offset(), originalPacket.lastSeenMessages().acknowledged())); // Restore the correct offset (copy packet here, packet itself is immutable record)
++        } else {
++            packet = originalPacket;
++        }
++        // Cheetah end
+         // CraftBukkit end
+         Optional<LastSeenMessages> optional = this.unpackAndApplyLastSeen(packet.lastSeenMessages());
+         if (!optional.isEmpty()) {
+@@ -2148,6 +_,13 @@
+                     return;
+                 }
+
++                // Cheetah start - Do not break message chain if proxy cancels a chat message
++                if (cancelled) {
++                    LOGGER.info("Skipping message of " + player.getScoreboardName() + ": '" + signedMessage.signedContent() + " because it was cancelled by BungeeCord.");
++                    return;
++                }
++                // Cheetah end
++
+                 CompletableFuture<FilteredText> completableFuture = this.filterTextPacket(signedMessage.signedContent()).thenApplyAsync(Function.identity(), this.server.chatExecutor); // CraftBukkit - async chat
+                 CompletableFuture<Component> componentFuture = this.server.getChatDecorator().decorate(this.player, null, signedMessage.decoratedContent()); // Paper - Adventure
+
+@@ -2200,8 +_,23 @@
+
+     @Override
+     public void handleSignedChatCommand(ServerboundChatCommandSignedPacket packet) {
++        // Cheetah start - Do not break message chain if proxy cancels a chat message
++        boolean cancelled = packet.lastSeenMessages().offset() < 0; // Same behavior as for ServerboundChatPacket
++        ServerboundChatCommandSignedPacket packet1;
++        if (cancelled) {
++            packet1 = new ServerboundChatCommandSignedPacket(packet.command(), packet.timeStamp(), packet.salt(), packet.argumentSignatures(), new LastSeenMessages.Update(packet.lastSeenMessages().offset() == Integer.MIN_VALUE ? 0 : -packet.lastSeenMessages().offset(), packet.lastSeenMessages().acknowledged())); // Restore the correct offset (copy packet here, packet itself is immutable record)
++        } else {
++            packet1 = packet;
++        }
++        // Cheetah end
+         Optional<LastSeenMessages> optional = this.unpackAndApplyLastSeen(packet.lastSeenMessages());
+         if (!optional.isEmpty()) {
++            // Cheetah start - Do not break message chain if proxy cancels a chat message
++            if (cancelled) {
++                LOGGER.info("Skipping command of " + player.getScoreboardName() + ": '" + packet1.command() + " because it was cancelled by BungeeCord.");
++                return;
++            }
++            // Cheetah end
+             this.tryHandleChat(packet.command(), () -> {
+                 // CraftBukkit start - SPIGOT-7346: Prevent disconnected players from executing commands
+                 if (this.player.hasDisconnected()) {
 @@ -2310,9 +_,20 @@
          return new SignedMessageChain.DecodeException(INVALID_COMMAND_SIGNATURE);
      }