Remove usage of sun.misc.Unsafe in BungeeViaInjector (#2698)

bungee/src/main/java/com/viaversion/viaversion/bungee/platform/BungeeViaInjector.java

@@ -17,46 +17,58 @@
  */
 package com.viaversion.viaversion.bungee.platform;
 
+import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
 import com.viaversion.viaversion.api.Via;
 import com.viaversion.viaversion.api.platform.ViaInjector;
 import com.viaversion.viaversion.bungee.handlers.BungeeChannelInitializer;
-import com.viaversion.viaversion.compatibility.ForcefulFieldModifier;
-import com.viaversion.viaversion.compatibility.unsafe.UnsafeBackedForcefulFieldModifier;
 import com.viaversion.viaversion.util.ReflectionUtil;
+import com.viaversion.viaversion.util.SetWrapper;
 import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelInitializer;
 import it.unimi.dsi.fastutil.ints.IntLinkedOpenHashSet;
 import it.unimi.dsi.fastutil.ints.IntSortedSet;
+import net.md_5.bungee.api.ProxyServer;
 
 import java.lang.reflect.Field;
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Set;
 
 public class BungeeViaInjector implements ViaInjector {
 
-    private final ForcefulFieldModifier forcefulFieldModifier;
+    private static final Field LISTENERS_FIELD;
+    private final List<Channel> injectedChannels = new ArrayList<>();
 
-    public BungeeViaInjector() {
+    static {
         try {
-            this.forcefulFieldModifier = new UnsafeBackedForcefulFieldModifier();
+            LISTENERS_FIELD = ProxyServer.getInstance().getClass().getDeclaredField("listeners");
-        } catch (final ReflectiveOperationException ex) {
+            LISTENERS_FIELD.setAccessible(true);
-            throw new IllegalStateException("Cannot create a modifier accessor", ex);
+        } catch (ReflectiveOperationException e) {
+            throw new RuntimeException("Unable to access listeners field.", e);
         }
     }
 
     @Override
-    public void inject() throws Exception {
+    @SuppressWarnings("unchecked")
+    public void inject() throws ReflectiveOperationException {
+        Set<Channel> listeners = (Set<Channel>) LISTENERS_FIELD.get(ProxyServer.getInstance());
+
+        // Inject the list
+        Set<Channel> wrapper = new SetWrapper<>(listeners, channel -> {
             try {
-            Class<?> pipelineUtils = Class.forName("net.md_5.bungee.netty.PipelineUtils");
+                injectChannel(channel);
-            Field field = pipelineUtils.getDeclaredField("SERVER_CHILD");
-            field.setAccessible(true);
-
-            BungeeChannelInitializer newInit = new BungeeChannelInitializer((ChannelInitializer<Channel>) field.get(null));
-
-            this.forcefulFieldModifier.setField(field, null, newInit);
             } catch (Exception e) {
-            Via.getPlatform().getLogger().severe("Unable to inject ViaVersion, please post these details on our GitHub and ensure you're using a compatible server version.");
+                throw new RuntimeException(e);
-            throw e;
+            }
+        });
+
+        LISTENERS_FIELD.set(ProxyServer.getInstance(), wrapper);
+
+        // Iterate through current list
+        for (Channel channel : listeners) {
+            injectChannel(channel);
         }
     }
 
@@ -65,6 +77,40 @@ public class BungeeViaInjector implements ViaInjector {
         Via.getPlatform().getLogger().severe("ViaVersion cannot remove itself from Bungee without a reboot!");
     }
 
+    @SuppressWarnings("unchecked")
+    private void injectChannel(Channel channel) throws ReflectiveOperationException {
+        List<String> names = channel.pipeline().names();
+        ChannelHandler bootstrapAcceptor = null;
+
+        for (String name : names) {
+            ChannelHandler handler = channel.pipeline().get(name);
+            try {
+                ReflectionUtil.get(handler, "childHandler", ChannelInitializer.class);
+                bootstrapAcceptor = handler;
+            } catch (Exception e) {
+                // Not this one
+            }
+        }
+
+        // Default to first
+        if (bootstrapAcceptor == null) {
+            bootstrapAcceptor = channel.pipeline().first();
+        }
+
+        if (bootstrapAcceptor.getClass().getName().equals("net.md_5.bungee.query.QueryHandler")) {
+            return;
+        }
+
+        try {
+            ChannelInitializer<Channel> oldInit = ReflectionUtil.get(bootstrapAcceptor, "childHandler", ChannelInitializer.class);
+            ChannelInitializer<Channel> newInit = new BungeeChannelInitializer(oldInit);
+
+            ReflectionUtil.set(bootstrapAcceptor, "childHandler", newInit);
+            this.injectedChannels.add(channel);
+        } catch (NoSuchFieldException e) {
+            throw new RuntimeException("Unable to find core component 'childHandler', please check your plugins. issue: " + bootstrapAcceptor.getClass().getName());
+        }
+    }
 
     @Override
     public int getServerProtocolVersion() throws Exception {
@@ -76,29 +122,64 @@ public class BungeeViaInjector implements ViaInjector {
         return new IntLinkedOpenHashSet(getBungeeSupportedVersions());
     }
 
+    @SuppressWarnings("unchecked")
     private List<Integer> getBungeeSupportedVersions() throws Exception {
         return ReflectionUtil.getStatic(Class.forName("net.md_5.bungee.protocol.ProtocolConstants"), "SUPPORTED_VERSION_IDS", List.class);
     }
 
-    private ChannelInitializer<Channel> getChannelInitializer() throws Exception {
-        Class<?> pipelineUtils = Class.forName("net.md_5.bungee.netty.PipelineUtils");
-        Field field = pipelineUtils.getDeclaredField("SERVER_CHILD");
-        field.setAccessible(true);
-        return (ChannelInitializer<Channel>) field.get(null);
-    }
-
     @Override
     public JsonObject getDump() {
         JsonObject data = new JsonObject();
+
+        // Generate information about current injections
+        JsonArray injectedChannelInitializers = new JsonArray();
+        for (Channel channel : this.injectedChannels) {
+            JsonObject channelInfo = new JsonObject();
+            channelInfo.addProperty("channelClass", channel.getClass().getName());
+
+            // Get information about the pipes for this channel
+            JsonArray pipeline = new JsonArray();
+            for (String pipeName : channel.pipeline().names()) {
+                JsonObject handlerInfo = new JsonObject();
+                handlerInfo.addProperty("name", pipeName);
+
+                ChannelHandler channelHandler = channel.pipeline().get(pipeName);
+                if (channelHandler == null) {
+                    handlerInfo.addProperty("status", "INVALID");
+                    continue;
+                }
+
+                handlerInfo.addProperty("class", channelHandler.getClass().getName());
+
                 try {
-            ChannelInitializer<Channel> initializer = getChannelInitializer();
+                    Object child = ReflectionUtil.get(channelHandler, "childHandler", ChannelInitializer.class);
-            data.addProperty("currentInitializer", initializer.getClass().getName());
+                    handlerInfo.addProperty("childClass", child.getClass().getName());
-            if (initializer instanceof BungeeChannelInitializer) {
+                    if (child instanceof BungeeChannelInitializer) {
-                data.addProperty("originalInitializer", ((BungeeChannelInitializer) initializer).getOriginal().getClass().getName());
+                        handlerInfo.addProperty("oldInit", ((BungeeChannelInitializer) child).getOriginal().getClass().getName());
                     }
-        } catch (Exception e) {
+                } catch (ReflectiveOperationException e) {
-            // Ignored, not printed in the dump
+                    // Don't display
                 }
+
+                pipeline.add(handlerInfo);
+            }
+            channelInfo.add("pipeline", pipeline);
+
+            injectedChannelInitializers.add(channelInfo);
+        }
+
+        data.add("injectedChannelInitializers", injectedChannelInitializers);
+
+        try {
+            Object list = LISTENERS_FIELD.get(ProxyServer.getInstance());
+            data.addProperty("currentList", list.getClass().getName());
+            if (list instanceof SetWrapper) {
+                data.addProperty("wrappedList", ((SetWrapper<?>) list).originalSet().getClass().getName());
+            }
+        } catch (ReflectiveOperationException ignored) {
+            // Ignored
+        }
+
         return data;
     }
 }

common/src/main/java/com/viaversion/viaversion/util/SetWrapper.java

@@ -0,0 +1,44 @@
+package com.viaversion.viaversion.util;
+
+import com.google.common.collect.ForwardingSet;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+import java.util.Collection;
+import java.util.Set;
+import java.util.function.Consumer;
+
+public class SetWrapper<E> extends ForwardingSet<E> {
+
+    private final Set<E> set;
+    private final Consumer<E> addListener;
+
+    public SetWrapper(Set<E> set, Consumer<E> addListener) {
+        this.set = set;
+        this.addListener = addListener;
+    }
+
+    @Override
+    public boolean add(@NonNull E element) {
+        addListener.accept(element);
+
+        return super.add(element);
+    }
+
+    @Override
+    public boolean addAll(Collection<? extends E> collection) {
+        for (E element : collection) {
+            addListener.accept(element);
+        }
+
+        return super.addAll(collection);
+    }
+
+    @Override
+    protected Set<E> delegate() {
+        return originalSet();
+    }
+
+    public Set<E> originalSet() {
+        return this.set;
+    }
+}

java-compat/java-compat-unsafe/src/main/java/com/viaversion/viaversion/compatibility/unsafe/UnsafeBackedForcefulFieldModifier.java

@@ -22,10 +22,14 @@ import com.viaversion.viaversion.compatibility.ForcefulFieldModifier;
 import java.lang.reflect.Field;
 import java.util.Objects;
 
+/**
+ * @deprecated usage of sun.misc.Unsafe is discouraged and can stop working in future Java releases.
+ */
 @SuppressWarnings({
         "java:S1191", // SonarLint/-Qube/-Cloud: We need Unsafe for the modifier implementation.
         "java:S3011", // ^: We need to circumvent the access restrictions of fields.
 })
+@Deprecated
 public final class UnsafeBackedForcefulFieldModifier implements ForcefulFieldModifier {
     private final sun.misc.Unsafe unsafe;