Upstream/Paper
1
0
Fork 0
mirror of https://github.com/PaperMC/Paper.git synced 2024-11-22 10:35:38 +01:00
Code Issues Projects Releases Wiki Activity
9c450388e1
Paper/patches/server/0946-Improve-tag-parser-handling.patch
Bjarne Koll c5a10665b8
Remove wall-time / unused skip tick protection (#11412) 
Spigot still maintains some partial implementation of "tick skipping", a
practice in which the MinecraftServer.currentTick field is updated not
by an increment of one per actual tick, but instead set to
System.currentTimeMillis() / 50. This behaviour means that the tracked
tick may "skip" a tick value in case a previous tick took more than the
expected 50ms.

To compensate for this in important paths, spigot/craftbukkit
implements "wall-time". Instead of incrementing/decrementing ticks on
block entities/entities by one for each call to their tick() method,
they instead increment/decrement important values, like
an ItemEntity's age or pickupDelay, by the difference of
`currentTick - lastTick`, where `lastTick` is the value of
`currentTick` during the last tick() call.

These "fixes" however do not play nicely with minecraft's simulation
distance as entities/block entities implementing the above behaviour
would "catch up" their values when moving from a non-ticking chunk to a
ticking one as their `lastTick` value remains stuck on the last tick in
a ticking chunk and hence lead to a large "catch up" once ticked again.

Paper completely removes the "tick skipping" behaviour (See patch
"Further-improve-server-tick-loop"), making the above precautions
completely unnecessary, which also rids paper of the previous described
incompatibility with non-ticking chunks.
2024-09-19 16:36:07 +02:00

282 lines
15 KiB
Diff
Raw Blame History

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Nassim Jahnke <nassim@njahnke.dev>
Date: Mon, 5 Feb 2024 11:54:04 +0100
Subject: [PATCH] Improve tag parser handling
diff --git a/src/main/java/com/mojang/brigadier/CommandDispatcher.java b/src/main/java/com/mojang/brigadier/CommandDispatcher.java
index 92848b64a78fce7a92e1657c2da6fc5ee53eea44..4b4f812eb13d5f03bcf3f8724d8aa8dbbc724e8b 100644
--- a/src/main/java/com/mojang/brigadier/CommandDispatcher.java
+++ b/src/main/java/com/mojang/brigadier/CommandDispatcher.java
@@ -304,9 +304,15 @@ public class CommandDispatcher<S> {
}
final CommandContextBuilder<S> context = contextSoFar.copy();
final StringReader reader = new StringReader(originalReader);
+ boolean stop = false; // Paper - Handle non-recoverable exceptions
try {
try {
child.parse(reader, context);
+ // Paper start - Handle non-recoverable exceptions
+ } catch (final io.papermc.paper.brigadier.TagParseCommandSyntaxException e) {
+ stop = true;
+ throw e;
+ // Paper end - Handle non-recoverable exceptions
} catch (final RuntimeException ex) {
throw CommandSyntaxException.BUILT_IN_EXCEPTIONS.dispatcherParseException().createWithContext(reader, ex.getMessage());
}
@@ -321,6 +327,7 @@ public class CommandDispatcher<S> {
}
errors.put(child, ex);
reader.setCursor(cursor);
+ if (stop) return new ParseResults<>(contextSoFar, originalReader, errors); // Paper - Handle non-recoverable exceptions
continue;
}
diff --git a/src/main/java/io/papermc/paper/brigadier/TagParseCommandSyntaxException.java b/src/main/java/io/papermc/paper/brigadier/TagParseCommandSyntaxException.java
new file mode 100644
index 0000000000000000000000000000000000000000..a375ad4ba9db990b24a2b9ff366fcba66b753815
--- /dev/null
+++ b/src/main/java/io/papermc/paper/brigadier/TagParseCommandSyntaxException.java
@@ -0,0 +1,15 @@
+package io.papermc.paper.brigadier;
+
+import com.mojang.brigadier.LiteralMessage;
+import com.mojang.brigadier.exceptions.CommandSyntaxException;
+import com.mojang.brigadier.exceptions.SimpleCommandExceptionType;
+import net.minecraft.network.chat.Component;
+
+public final class TagParseCommandSyntaxException extends CommandSyntaxException {
+
+ private static final SimpleCommandExceptionType EXCEPTION_TYPE = new SimpleCommandExceptionType(new LiteralMessage("Error parsing NBT"));
+
+ public TagParseCommandSyntaxException(final String message) {
+ super(EXCEPTION_TYPE, Component.literal(message));
+ }
+}
diff --git a/src/main/java/net/minecraft/nbt/TagParser.java b/src/main/java/net/minecraft/nbt/TagParser.java
index da101bca71f4710812621b98f0a0d8cab180346a..3cd112584accb8e8f050ac99738eed11c902e60e 100644
--- a/src/main/java/net/minecraft/nbt/TagParser.java
+++ b/src/main/java/net/minecraft/nbt/TagParser.java
@@ -49,6 +49,7 @@ public class TagParser {
}, CompoundTag::toString);
public static final Codec<CompoundTag> LENIENT_CODEC = Codec.withAlternative(AS_CODEC, CompoundTag.CODEC);
private final StringReader reader;
+ private int depth; // Paper
public static CompoundTag parseTag(String string) throws CommandSyntaxException {
return new TagParser(new StringReader(string)).readSingleStruct();
@@ -159,6 +160,7 @@ public class TagParser {
public CompoundTag readStruct() throws CommandSyntaxException {
this.expect('{');
+ this.increaseDepth(); // Paper
CompoundTag compoundTag = new CompoundTag();
this.reader.skipWhitespace();
@@ -182,6 +184,7 @@ public class TagParser {
}
this.expect('}');
+ this.depth--; // Paper
return compoundTag;
}
@@ -191,6 +194,7 @@ public class TagParser {
if (!this.reader.canRead()) {
throw ERROR_EXPECTED_VALUE.createWithContext(this.reader);
} else {
+ this.increaseDepth(); // Paper
ListTag listTag = new ListTag();
TagType<?> tagType = null;
@@ -216,6 +220,7 @@ public class TagParser {
}
this.expect(']');
+ this.depth--; // Paper
return listTag;
}
}
@@ -288,4 +293,11 @@ public class TagParser {
this.reader.skipWhitespace();
this.reader.expect(c);
}
+
+ private void increaseDepth() throws CommandSyntaxException {
+ this.depth++;
+ if (this.depth > 512) {
+ throw new io.papermc.paper.brigadier.TagParseCommandSyntaxException("NBT tag is too complex, depth > 512");
+ }
+ }
}
diff --git a/src/main/java/net/minecraft/network/chat/ComponentUtils.java b/src/main/java/net/minecraft/network/chat/ComponentUtils.java
index 3365aed2b67ae0e4dd0410f5190ba474f146139b..8b776434a733b91129b089d702b2583b727bf3d2 100644
--- a/src/main/java/net/minecraft/network/chat/ComponentUtils.java
+++ b/src/main/java/net/minecraft/network/chat/ComponentUtils.java
@@ -33,10 +33,30 @@ public class ComponentUtils {
}
}
+ @io.papermc.paper.annotation.DoNotUse // Paper - validate separators - right now this method is only used for separator evaluation. Error on build if this changes to re-evaluate.
public static Optional<MutableComponent> updateForEntity(@Nullable CommandSourceStack source, Optional<Component> text, @Nullable Entity sender, int depth) throws CommandSyntaxException {
return text.isPresent() ? Optional.of(updateForEntity(source, text.get(), sender, depth)) : Optional.empty();
}
+ // Paper start - validate separator
+ public static Optional<MutableComponent> updateSeparatorForEntity(@Nullable CommandSourceStack source, Optional<Component> text, @Nullable Entity sender, int depth) throws CommandSyntaxException {
+ if (text.isEmpty() || !isValidSelector(text.get())) return Optional.empty();
+ return Optional.of(updateForEntity(source, text.get(), sender, depth));
+ }
+ public static boolean isValidSelector(final Component component) {
+ final ComponentContents contents = component.getContents();
+
+ if (contents instanceof net.minecraft.network.chat.contents.NbtContents || contents instanceof net.minecraft.network.chat.contents.SelectorContents) return false;
+ if (contents instanceof final net.minecraft.network.chat.contents.TranslatableContents translatableContents) {
+ for (final Object arg : translatableContents.getArgs()) {
+ if (arg instanceof final Component argumentAsComponent && !isValidSelector(argumentAsComponent)) return false;
+ }
+ }
+
+ return true;
+ }
+ // Paper end - validate separator
+
public static MutableComponent updateForEntity(@Nullable CommandSourceStack source, Component text, @Nullable Entity sender, int depth) throws CommandSyntaxException {
if (depth > 100) {
return text.copy();
diff --git a/src/main/java/net/minecraft/network/chat/contents/NbtContents.java b/src/main/java/net/minecraft/network/chat/contents/NbtContents.java
index df26c39a2bb20e2021b50211dce905483a77f4e6..5634122dac8afeecab0cde623e9868d8e865e02a 100644
--- a/src/main/java/net/minecraft/network/chat/contents/NbtContents.java
+++ b/src/main/java/net/minecraft/network/chat/contents/NbtContents.java
@@ -120,7 +120,7 @@ public class NbtContents implements ComponentContents {
}).map(Tag::getAsString);
if (this.interpreting) {
Component component = DataFixUtils.orElse(
- ComponentUtils.updateForEntity(source, this.separator, sender, depth), ComponentUtils.DEFAULT_NO_STYLE_SEPARATOR
+ ComponentUtils.updateSeparatorForEntity(source, this.separator, sender, depth), ComponentUtils.DEFAULT_NO_STYLE_SEPARATOR // Paper - validate separator
);
return stream.flatMap(text -> {
try {
@@ -132,7 +132,7 @@ public class NbtContents implements ComponentContents {
}
}).reduce((accumulator, current) -> accumulator.append(component).append(current)).orElseGet(Component::empty);
} else {
- return ComponentUtils.updateForEntity(source, this.separator, sender, depth)
+ return ComponentUtils.updateSeparatorForEntity(source, this.separator, sender, depth) // Paper - validate separator
.map(
text -> stream.map(Component::literal)
.reduce((accumulator, current) -> accumulator.append(text).append(current))
diff --git a/src/main/java/net/minecraft/network/chat/contents/SelectorContents.java b/src/main/java/net/minecraft/network/chat/contents/SelectorContents.java
index 1337853badf8e124aa8439ce33a255bc4164125b..933388a60eda2af259d4ef761e31c5abb69c31fd 100644
--- a/src/main/java/net/minecraft/network/chat/contents/SelectorContents.java
+++ b/src/main/java/net/minecraft/network/chat/contents/SelectorContents.java
@@ -50,7 +50,7 @@ public class SelectorContents implements ComponentContents {
EntitySelectorParser entitySelectorParser = new EntitySelectorParser(new StringReader(pattern), true);
entitySelector = entitySelectorParser.parse();
} catch (CommandSyntaxException var3) {
- LOGGER.warn("Invalid selector component: {}: {}", pattern, var3.getMessage());
+ return null; // Paper
}
return entitySelector;
@@ -77,7 +77,7 @@ public class SelectorContents implements ComponentContents {
@Override
public MutableComponent resolve(@Nullable CommandSourceStack source, @Nullable Entity sender, int depth) throws CommandSyntaxException {
if (source != null && this.selector != null) {
- Optional<? extends Component> optional = ComponentUtils.updateForEntity(source, this.separator, sender, depth);
+ Optional<? extends Component> optional = ComponentUtils.updateSeparatorForEntity(source, this.separator, sender, depth); // Paper - validate separator
return ComponentUtils.formatList(this.selector.findEntities(source), optional, Entity::getDisplayName);
} else {
return Component.empty();
diff --git a/src/main/java/net/minecraft/network/chat/contents/TranslatableContents.java b/src/main/java/net/minecraft/network/chat/contents/TranslatableContents.java
index 56e641bc5f6edc657647993ea2efbb7bb9c2f732..4aa6232bf0f72fcde32d257100bd15b1c5192aaa 100644
--- a/src/main/java/net/minecraft/network/chat/contents/TranslatableContents.java
+++ b/src/main/java/net/minecraft/network/chat/contents/TranslatableContents.java
@@ -181,6 +181,15 @@ public class TranslatableContents implements ComponentContents {
@Override
public <T> Optional<T> visit(FormattedText.ContentConsumer<T> visitor) {
+ // Paper start - Count visited parts
+ try {
+ return this.visit(new TranslatableContentConsumer<>(visitor));
+ } catch (IllegalArgumentException ignored) {
+ return visitor.accept("...");
+ }
+ }
+ private <T> Optional<T> visit(TranslatableContentConsumer<T> visitor) {
+ // Paper end - Count visited parts
this.decompose();
for (FormattedText formattedText : this.decomposedParts) {
@@ -192,6 +201,25 @@ public class TranslatableContents implements ComponentContents {
return Optional.empty();
}
+ // Paper start - Count visited parts
+ private static final class TranslatableContentConsumer<T> implements FormattedText.ContentConsumer<T> {
+ private static final IllegalArgumentException EX = new IllegalArgumentException("Too long");
+ private final FormattedText.ContentConsumer<T> visitor;
+ private int visited;
+
+ private TranslatableContentConsumer(FormattedText.ContentConsumer<T> visitor) {
+ this.visitor = visitor;
+ }
+
+ @Override
+ public Optional<T> accept(final String asString) {
+ if (visited++ > 32) {
+ throw EX;
+ }
+ return this.visitor.accept(asString);
+ }
+ }
+ // Paper end - Count visited parts
@Override
public MutableComponent resolve(@Nullable CommandSourceStack source, @Nullable Entity sender, int depth) throws CommandSyntaxException {
diff --git a/src/main/java/net/minecraft/network/protocol/game/ServerboundCommandSuggestionPacket.java b/src/main/java/net/minecraft/network/protocol/game/ServerboundCommandSuggestionPacket.java
index 898b19887ed34c87003fc63cb5905df2ba6234a5..b47eeb23055b135d5567552ba983bfbc3e1fab67 100644
--- a/src/main/java/net/minecraft/network/protocol/game/ServerboundCommandSuggestionPacket.java
+++ b/src/main/java/net/minecraft/network/protocol/game/ServerboundCommandSuggestionPacket.java
@@ -19,7 +19,7 @@ public class ServerboundCommandSuggestionPacket implements Packet<ServerGamePack
private ServerboundCommandSuggestionPacket(FriendlyByteBuf buf) {
this.id = buf.readVarInt();
- this.command = buf.readUtf(32500);
+ this.command = buf.readUtf(2048); // Paper
}
private void write(FriendlyByteBuf buf) {
diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index fb935b505ec048522f9ab5d689b2c64c64f401a7..e0c46e548a34c963750c9411dfd3c0946d67a7c7 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -766,6 +766,13 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
return;
}
// Paper end - Don't suggest if tab-complete is disabled
+ // Paper start
+ final int index;
+ if (packet.getCommand().length() > 64 && ((index = packet.getCommand().indexOf(' ')) == -1 || index >= 64)) {
+ this.disconnect(Component.translatable("disconnect.spam"), org.bukkit.event.player.PlayerKickEvent.Cause.SPAM);
+ return;
+ }
+ // Paper end
// Paper start - AsyncTabCompleteEvent
TAB_COMPLETE_EXECUTOR.execute(() -> this.handleCustomCommandSuggestions0(packet));
}
@@ -818,6 +825,13 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
private void sendServerSuggestions(final ServerboundCommandSuggestionPacket packet, final StringReader stringreader) {
// Paper end - AsyncTabCompleteEvent
ParseResults<CommandSourceStack> parseresults = this.server.getCommands().getDispatcher().parse(stringreader, this.player.createCommandSourceStack());
+ // Paper start - Handle non-recoverable exceptions
+ if (!parseresults.getExceptions().isEmpty()
+ && parseresults.getExceptions().values().stream().anyMatch(e -> e instanceof io.papermc.paper.brigadier.TagParseCommandSyntaxException)) {
+ this.disconnect(Component.translatable("disconnect.spam"), org.bukkit.event.player.PlayerKickEvent.Cause.SPAM);
+ return;
+ }
+ // Paper end - Handle non-recoverable exceptions
this.server.getCommands().getDispatcher().getCompletionSuggestions(parseresults).thenAccept((suggestions) -> {
// Paper start - Don't tab-complete namespaced commands if send-namespaced is false
Reference in New Issue View Git Blame Copy Permalink