💥 Attempt to avoid decryption error

AzisabaNetwork · Aug 26, 2022 · f69b301 · f69b301
1 parent e527443
commit f69b301
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Showing 14 changed files with 161 additions and 36 deletions.
diff --git a/api/src/main/java/net/azisaba/azipluginmessaging/api/protocol/Protocol.java b/api/src/main/java/net/azisaba/azipluginmessaging/api/protocol/Protocol.java
@@ -8,6 +8,7 @@
 import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundCheckRankExpirationPacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundClearPrefixPacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundEncryptionPacket;
+import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundEncryptionResponsePacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundGiveGamingSaraPacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundGiveNitroSaraPacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ProxyboundGiveSaraPacket;
@@ -21,6 +22,8 @@
 import net.azisaba.azipluginmessaging.api.protocol.handler.ServerboundActionResponsePacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ServerboundCheckRankExpirationPacket;
 import net.azisaba.azipluginmessaging.api.protocol.handler.ServerboundEncryptionPacket;
+import net.azisaba.azipluginmessaging.api.protocol.handler.ServerboundEncryptionResponsePacket;
+import net.azisaba.azipluginmessaging.api.protocol.message.EmptyMessage;
 import net.azisaba.azipluginmessaging.api.protocol.message.EncryptionMessage;
 import net.azisaba.azipluginmessaging.api.protocol.message.Message;
 import net.azisaba.azipluginmessaging.api.protocol.message.PlayerMessage;
@@ -47,6 +50,7 @@
 import java.io.IOException;
 import java.util.Collection;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
 
 public final class Protocol<T extends MessageHandler<M>, M extends Message> {
@@ -64,21 +68,23 @@ public final class Protocol<T extends MessageHandler<M>, M extends Message> {
     public static final String CHANNEL_ID = "azipm:main";
 
     public static final Protocol<ProxyboundEncryptionPacket, EncryptionMessage> P_ENCRYPTION = new Protocol<>(PacketFlow.TO_PROXY, 0x00, new ProxyboundEncryptionPacket());
-    public static final Protocol<ProxyboundSetRankPacket, ProxyboundSetRankMessage> P_SET_RANK = new Protocol<>(PacketFlow.TO_PROXY, 0x01, new ProxyboundSetRankPacket());
-    public static final Protocol<ProxyboundGiveGamingSaraPacket, PlayerMessage> P_GIVE_GAMING_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x02, new ProxyboundGiveGamingSaraPacket());
-    public static final Protocol<ProxyboundGiveSaraPacket, ProxyboundGiveSaraMessage> P_GIVE_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x03, new ProxyboundGiveSaraPacket());
-    public static final Protocol<ProxyboundToggleGamingSaraPacket, PlayerMessage> P_TOGGLE_GAMING_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x04, new ProxyboundToggleGamingSaraPacket());
-    public static final Protocol<ProxyboundToggleSaraHidePacket, PlayerMessage> P_TOGGLE_SARA_HIDE = new Protocol<>(PacketFlow.TO_PROXY, 0x05, new ProxyboundToggleSaraHidePacket()); // non-contextual
-    public static final Protocol<ProxyboundToggleSaraShowPacket, PlayerWithServerMessage> P_TOGGLE_SARA_SHOW = new Protocol<>(PacketFlow.TO_PROXY, 0x06, new ProxyboundToggleSaraShowPacket()); // contextual
-    public static final Protocol<ProxyboundSetPrefixPacket, ProxyboundSetPrefixMessage> P_SET_PREFIX = new Protocol<>(PacketFlow.TO_PROXY, 0x07, new ProxyboundSetPrefixPacket()); // may be contextual
-    public static final Protocol<ProxyboundClearPrefixPacket, ProxyboundClearPrefixMessage> P_CLEAR_PREFIX = new Protocol<>(PacketFlow.TO_PROXY, 0x08, new ProxyboundClearPrefixPacket()); // may be contextual
-    public static final Protocol<ProxyboundGiveNitroSaraPacket, ProxyboundGiveNitroSaraMessage> P_GIVE_NITRO_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x09, new ProxyboundGiveNitroSaraPacket());
-    public static final Protocol<ProxyboundToggleNitroSaraPacket, PlayerMessage> P_TOGGLE_NITRO_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x0A, new ProxyboundToggleNitroSaraPacket());
-    public static final Protocol<ProxyboundCheckRankExpirationPacket, ProxyboundCheckRankExpirationMessage> P_CHECK_RANK_EXPIRATION = new Protocol<>(PacketFlow.TO_PROXY, 0x0B, new ProxyboundCheckRankExpirationPacket());
+    public static final Protocol<ProxyboundEncryptionResponsePacket, EmptyMessage> P_ENCRYPTION_RESPONSE = new Protocol<>(PacketFlow.TO_PROXY, 0x01, new ProxyboundEncryptionResponsePacket());
+    public static final Protocol<ProxyboundSetRankPacket, ProxyboundSetRankMessage> P_SET_RANK = new Protocol<>(PacketFlow.TO_PROXY, 0x02, new ProxyboundSetRankPacket());
+    public static final Protocol<ProxyboundGiveGamingSaraPacket, PlayerMessage> P_GIVE_GAMING_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x03, new ProxyboundGiveGamingSaraPacket());
+    public static final Protocol<ProxyboundGiveSaraPacket, ProxyboundGiveSaraMessage> P_GIVE_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x04, new ProxyboundGiveSaraPacket());
+    public static final Protocol<ProxyboundToggleGamingSaraPacket, PlayerMessage> P_TOGGLE_GAMING_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x05, new ProxyboundToggleGamingSaraPacket());
+    public static final Protocol<ProxyboundToggleSaraHidePacket, PlayerMessage> P_TOGGLE_SARA_HIDE = new Protocol<>(PacketFlow.TO_PROXY, 0x06, new ProxyboundToggleSaraHidePacket()); // non-contextual
+    public static final Protocol<ProxyboundToggleSaraShowPacket, PlayerWithServerMessage> P_TOGGLE_SARA_SHOW = new Protocol<>(PacketFlow.TO_PROXY, 0x07, new ProxyboundToggleSaraShowPacket()); // contextual
+    public static final Protocol<ProxyboundSetPrefixPacket, ProxyboundSetPrefixMessage> P_SET_PREFIX = new Protocol<>(PacketFlow.TO_PROXY, 0x08, new ProxyboundSetPrefixPacket()); // may be contextual
+    public static final Protocol<ProxyboundClearPrefixPacket, ProxyboundClearPrefixMessage> P_CLEAR_PREFIX = new Protocol<>(PacketFlow.TO_PROXY, 0x09, new ProxyboundClearPrefixPacket()); // may be contextual
+    public static final Protocol<ProxyboundGiveNitroSaraPacket, ProxyboundGiveNitroSaraMessage> P_GIVE_NITRO_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x0A, new ProxyboundGiveNitroSaraPacket());
+    public static final Protocol<ProxyboundToggleNitroSaraPacket, PlayerMessage> P_TOGGLE_NITRO_SARA = new Protocol<>(PacketFlow.TO_PROXY, 0x0B, new ProxyboundToggleNitroSaraPacket());
+    public static final Protocol<ProxyboundCheckRankExpirationPacket, ProxyboundCheckRankExpirationMessage> P_CHECK_RANK_EXPIRATION = new Protocol<>(PacketFlow.TO_PROXY, 0x0C, new ProxyboundCheckRankExpirationPacket());
 
     public static final Protocol<ServerboundEncryptionPacket, EncryptionMessage> S_ENCRYPTION = new Protocol<>(PacketFlow.TO_SERVER, 0x00, new ServerboundEncryptionPacket());
-    public static final Protocol<ServerboundActionResponsePacket, ServerboundActionResponseMessage> S_ACTION_RESPONSE = new Protocol<>(PacketFlow.TO_SERVER, 0x01, new ServerboundActionResponsePacket());
-    public static final Protocol<ServerboundCheckRankExpirationPacket, ServerboundCheckRankExpirationMessage> S_CHECK_RANK_EXPIRATION = new Protocol<>(PacketFlow.TO_SERVER, 0x02, new ServerboundCheckRankExpirationPacket());
+    public static final Protocol<ServerboundEncryptionResponsePacket, EmptyMessage> S_ENCRYPTION_RESPONSE = new Protocol<>(PacketFlow.TO_SERVER, 0x01, new ServerboundEncryptionResponsePacket());
+    public static final Protocol<ServerboundActionResponsePacket, ServerboundActionResponseMessage> S_ACTION_RESPONSE = new Protocol<>(PacketFlow.TO_SERVER, 0x02, new ServerboundActionResponsePacket());
+    public static final Protocol<ServerboundCheckRankExpirationPacket, ServerboundCheckRankExpirationMessage> S_CHECK_RANK_EXPIRATION = new Protocol<>(PacketFlow.TO_SERVER, 0x03, new ServerboundCheckRankExpirationPacket());
 
     private final PacketFlow packetFlow;
     private final byte id;
@@ -186,7 +192,8 @@ public boolean sendPacket(@Nullable PacketSender sender, @NotNull M msg) {
      */
     public static void handleProxySide(ServerConnection server, byte[] rawData) {
         byte[] data;
-        if (server.isEncrypted()) {
+        boolean encrypted = server.isEncrypted() || server.consumeEncryptedOnce();
+        if (encrypted) {
             try {
                 data = EncryptionUtil.decrypt(rawData, server.getKeyPair().getPrivate());
             } catch (Exception e) {
@@ -198,7 +205,7 @@ public static void handleProxySide(ServerConnection server, byte[] rawData) {
         try (ByteArrayInputStream bin = new ByteArrayInputStream(data);
              DataInputStream in = new DataInputStream(bin)) {
             byte id = (byte) (in.readByte() & 0xFF);
-            if (id != 0 && !server.isEncrypted()) {
+            if (id != 0 && !encrypted) {
                 throw new RuntimeException("Packet " + id + " must be received encrypted (server: " + server + ")");
             }
             Protocol<?, ?> protocol = Protocol.getById(PacketFlow.TO_PROXY, id);
@@ -219,6 +226,7 @@ public static void handleProxySide(ServerConnection server, byte[] rawData) {
             @SuppressWarnings("unchecked")
             ProxyMessageHandler<Message> handler = (ProxyMessageHandler<Message>) protocol.getHandler();
             Message message = handler.read(server, in);
+            Objects.requireNonNull(message, "handler.read(in) returned null");
             handler.handle(server, message);
         } catch (Exception | AssertionError e) {
             Logger.getCurrentLogger().warn("Failed to handle plugin message from " + server, e);
@@ -233,7 +241,8 @@ public static void handleProxySide(ServerConnection server, byte[] rawData) {
      */
     public static void handleServerSide(@NotNull PacketSender sender, byte[] rawData) {
         byte[] data;
-        if (sender.isEncrypted()) {
+        boolean encrypted = sender.isEncrypted() || sender.consumeEncryptedOnce();
+        if (encrypted) {
             try {
                 data = EncryptionUtil.decrypt(rawData, sender.getKeyPair().getPrivate());
             } catch (Exception e) {
@@ -245,7 +254,7 @@ public static void handleServerSide(@NotNull PacketSender sender, byte[] rawData
         try (ByteArrayInputStream bin = new ByteArrayInputStream(data);
              DataInputStream in = new DataInputStream(bin)) {
             byte id = (byte) (in.readByte() & 0xFF);
-            if (id != 0 && !sender.isEncrypted()) {
+            if (id != 0 && !encrypted) {
                 throw new RuntimeException("Packet " + id + " must be received encrypted (sender: " + sender + ")");
             }
             Protocol<?, ?> protocol = Protocol.getById(PacketFlow.TO_SERVER, id);
@@ -264,6 +273,7 @@ public static void handleServerSide(@NotNull PacketSender sender, byte[] rawData
             @SuppressWarnings("unchecked")
             ServerMessageHandler<Message> handler = (ServerMessageHandler<Message>) protocol.getHandler();
             Message message = handler.read(in);
+            Objects.requireNonNull(message, "handler.read(in) returned null");
             handler.handle(sender, message);
         } catch (Exception | AssertionError e) {
             Logger.getCurrentLogger().warn("Failed to handle plugin message from " + sender, e);

diff --git a/.../java/net/azisaba/azipluginmessaging/api/protocol/handler/ProxyboundEncryptionPacket.java b/.../java/net/azisaba/azipluginmessaging/api/protocol/handler/ProxyboundEncryptionPacket.java
@@ -1,6 +1,5 @@
 package net.azisaba.azipluginmessaging.api.protocol.handler;
 
-import net.azisaba.azipluginmessaging.api.AziPluginMessagingConfig;
 import net.azisaba.azipluginmessaging.api.Logger;
 import net.azisaba.azipluginmessaging.api.protocol.Protocol;
 import net.azisaba.azipluginmessaging.api.protocol.message.EncryptionMessage;
@@ -40,11 +39,7 @@ public void handle(@NotNull PacketSender sender, @NotNull EncryptionMessage msg)
             Logger.getCurrentLogger().warn("Failed to send public key to the server " + sender);
         }
 
-        // Enable encryption
-        sender.setEncrypted(true);
-
-        if (AziPluginMessagingConfig.debug) {
-            Logger.getCurrentLogger().info("Encryption enabled for " + sender);
-        }
+        // Enable encryption here, otherwise we will not be able to receive the encrypted response
+        sender.setEncryptedOnce();
     }
 }
diff --git a/...t/azisaba/azipluginmessaging/api/protocol/handler/ProxyboundEncryptionResponsePacket.java b/...t/azisaba/azipluginmessaging/api/protocol/handler/ProxyboundEncryptionResponsePacket.java
@@ -0,0 +1,32 @@
+package net.azisaba.azipluginmessaging.api.protocol.handler;
+
+import net.azisaba.azipluginmessaging.api.AziPluginMessagingConfig;
+import net.azisaba.azipluginmessaging.api.Logger;
+import net.azisaba.azipluginmessaging.api.protocol.Protocol;
+import net.azisaba.azipluginmessaging.api.protocol.message.EmptyMessage;
+import net.azisaba.azipluginmessaging.api.server.PacketSender;
+import net.azisaba.azipluginmessaging.api.server.ServerConnection;
+import org.jetbrains.annotations.NotNull;
+
+import java.io.DataInputStream;
+import java.io.IOException;
+
+public class ProxyboundEncryptionResponsePacket implements ProxyMessageHandler<EmptyMessage> {
+    @Override
+    public @NotNull EmptyMessage read(@NotNull ServerConnection server, @NotNull DataInputStream in) throws IOException {
+        return EmptyMessage.INSTANCE;
+    }
+
+    @Override
+    public void handle(@NotNull PacketSender sender, @NotNull EmptyMessage msg) throws Exception {
+        // Enable encryption
+        sender.setEncrypted(true);
+
+        if (AziPluginMessagingConfig.debug) {
+            Logger.getCurrentLogger().info("Encryption enabled for " + sender);
+        }
+
+        // Send response to server to set the "encrypted" flag to true
+        Protocol.S_ENCRYPTION_RESPONSE.sendPacket(sender, EmptyMessage.INSTANCE);
+    }
+}
diff --git a/...java/net/azisaba/azipluginmessaging/api/protocol/handler/ServerboundEncryptionPacket.java b/...java/net/azisaba/azipluginmessaging/api/protocol/handler/ServerboundEncryptionPacket.java
@@ -1,9 +1,8 @@
 package net.azisaba.azipluginmessaging.api.protocol.handler;
 
-import net.azisaba.azipluginmessaging.api.AziPluginMessagingConfig;
-import net.azisaba.azipluginmessaging.api.AziPluginMessagingProvider;
-import net.azisaba.azipluginmessaging.api.Logger;
 import net.azisaba.azipluginmessaging.api.entity.Player;
+import net.azisaba.azipluginmessaging.api.protocol.Protocol;
+import net.azisaba.azipluginmessaging.api.protocol.message.EmptyMessage;
 import net.azisaba.azipluginmessaging.api.protocol.message.EncryptionMessage;
 import net.azisaba.azipluginmessaging.api.server.PacketSender;
 import org.jetbrains.annotations.NotNull;
@@ -33,13 +32,15 @@ public void handle(@NotNull PacketSender sender, @NotNull EncryptionMessage msg)
         // Set the public key from the proxy
         sender.setRemotePublicKey(msg.getPublicKey());
 
-        // Enable encryption
+        // Enable encryption to be able to send packet
         sender.setEncrypted(true);
-
-        if (AziPluginMessagingConfig.debug) {
-            Logger.getCurrentLogger().info("Encryption enabled for " + sender);
+        sender.setEncryptedOnce();
+        try {
+            // Send response to proxy
+            Protocol.P_ENCRYPTION_RESPONSE.sendPacket(sender, EmptyMessage.INSTANCE);
+        } finally {
+            // Disable encryption because response is not guaranteed to be received on our side
+            sender.setEncrypted(false);
         }
-
-        AziPluginMessagingProvider.get().getPacketQueue().flush(sender);
     }
 }
diff --git a/.../azisaba/azipluginmessaging/api/protocol/handler/ServerboundEncryptionResponsePacket.java b/.../azisaba/azipluginmessaging/api/protocol/handler/ServerboundEncryptionResponsePacket.java
@@ -0,0 +1,30 @@
+package net.azisaba.azipluginmessaging.api.protocol.handler;
+
+import net.azisaba.azipluginmessaging.api.AziPluginMessagingConfig;
+import net.azisaba.azipluginmessaging.api.AziPluginMessagingProvider;
+import net.azisaba.azipluginmessaging.api.Logger;
+import net.azisaba.azipluginmessaging.api.protocol.message.EmptyMessage;
+import net.azisaba.azipluginmessaging.api.server.PacketSender;
+import org.jetbrains.annotations.NotNull;
+
+import java.io.DataInputStream;
+import java.io.IOException;
+
+public class ServerboundEncryptionResponsePacket implements ServerMessageHandler<EmptyMessage> {
+    @Override
+    public @NotNull EmptyMessage read(@NotNull DataInputStream in) throws IOException {
+        return EmptyMessage.INSTANCE;
+    }
+
+    @Override
+    public void handle(@NotNull PacketSender sender, @NotNull EmptyMessage msg) throws Exception {
+        // Enable encryption
+        sender.setEncrypted(true);
+
+        if (AziPluginMessagingConfig.debug) {
+            Logger.getCurrentLogger().info("Encryption enabled for " + sender);
+        }
+
+        AziPluginMessagingProvider.get().getPacketQueue().flush(sender);
+    }
+}
diff --git a/api/src/main/java/net/azisaba/azipluginmessaging/api/protocol/message/EmptyMessage.java b/api/src/main/java/net/azisaba/azipluginmessaging/api/protocol/message/EmptyMessage.java
@@ -0,0 +1,17 @@
+package net.azisaba.azipluginmessaging.api.protocol.message;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+public class EmptyMessage implements Message {
+    public static final EmptyMessage INSTANCE = new EmptyMessage();
+
+    private EmptyMessage() {}
+
+    @Override
+    public void write(@NotNull DataOutputStream out) throws IOException {
+        // no-op
+    }
+}
diff --git a/api/src/main/java/net/azisaba/azipluginmessaging/api/server/Connection.java b/api/src/main/java/net/azisaba/azipluginmessaging/api/server/Connection.java
@@ -21,6 +21,10 @@ public interface Connection {
      */
     boolean isEncrypted();
 
+    void setEncryptedOnce();
+
+    boolean consumeEncryptedOnce();
+
     /**
      * Gets the local key pair for encrypting packets.
      * @return the local key pair

diff --git a/api/src/main/java/net/azisaba/azipluginmessaging/api/server/PacketSender.java b/api/src/main/java/net/azisaba/azipluginmessaging/api/server/PacketSender.java
@@ -2,7 +2,6 @@
 
 import org.jetbrains.annotations.NotNull;
 
-import java.security.KeyPair;
 import java.security.PublicKey;
 
 /**

diff --git a/api/src/test/java/net/azisaba/azipluginmessaging/test/ProtocolTest.java b/api/src/test/java/net/azisaba/azipluginmessaging/test/ProtocolTest.java
@@ -7,6 +7,7 @@
 public class ProtocolTest {
     @Test
     public void load() {
+        // check packets
         Protocol.getById(PacketFlow.TO_SERVER, (byte) 0);
     }
 }
diff --git a/build.gradle.kts b/build.gradle.kts
@@ -6,7 +6,7 @@ plugins {
 }
 
 group = "net.azisaba.azipluginmessaging"
-version = "2.3.1-SNAPSHOT"
+version = "3.0.0"
 
 repositories {
     mavenCentral()

diff --git a/spigot/build.gradle.kts b/spigot/build.gradle.kts
@@ -14,6 +14,18 @@ dependencies {
 }
 
 tasks {
+    processResources {
+        from(sourceSets.main.get().resources.srcDirs) {
+            include("**")
+            val tokenReplacementMap = mapOf(
+                "VERSION" to project.version
+            )
+            filter<org.apache.tools.ant.filters.ReplaceTokens>("tokens" to tokenReplacementMap)
+        }
+        filteringCharset = "UTF-8"
+        duplicatesStrategy = DuplicatesStrategy.INCLUDE
+    }
+
     shadowJar {
         archiveFileName.set("AziPluginMessaging-Spigot-${project.version}.jar")
     }

diff --git a/spigot/src/main/java/net/azisaba/azipluginmessaging/spigot/entity/PlayerImpl.java b/spigot/src/main/java/net/azisaba/azipluginmessaging/spigot/entity/PlayerImpl.java
@@ -15,6 +15,7 @@
 import java.util.Objects;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 
 public class PlayerImpl implements Player, PacketSender {
@@ -25,6 +26,7 @@ public class PlayerImpl implements Player, PacketSender {
     private boolean encrypted = false;
     public String challenge = null;
     public AtomicInteger joins = new AtomicInteger();
+    private final AtomicBoolean encryptedOnce = new AtomicBoolean(false);
 
     @Contract(value = "null -> fail", pure = true)
     private PlayerImpl(@Nullable org.bukkit.entity.Player handle) {
@@ -90,6 +92,16 @@ public boolean isEncrypted() {
         return this.encrypted;
     }
 
+    @Override
+    public void setEncryptedOnce() {
+        encryptedOnce.set(true);
+    }
+
+    @Override
+    public boolean consumeEncryptedOnce() {
+        return encryptedOnce.compareAndSet(true, false);
+    }
+
     @NotNull
     @Override
     public PublicKey getRemotePublicKey() {

diff --git a/spigot/src/main/resources/plugin.yml b/spigot/src/main/resources/plugin.yml
@@ -1,6 +1,6 @@
 name: AziPluginMessaging
 main: net.azisaba.azipluginmessaging.spigot.SpigotPlugin
-version: 2.3.0-SNAPSHOT
+version: @VERSION@
 depend:
   - LuckPerms
 commands:

diff --git a/...ty/src/main/java/net/azisaba/azipluginmessaging/velocity/server/ServerConnectionImpl.java b/...ty/src/main/java/net/azisaba/azipluginmessaging/velocity/server/ServerConnectionImpl.java
@@ -18,6 +18,7 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 public class ServerConnectionImpl implements ServerConnection {
     private static long lastCleaned = System.currentTimeMillis();
@@ -26,6 +27,7 @@ public class ServerConnectionImpl implements ServerConnection {
     private KeyPair keyPair;
     private PublicKey publicKey;
     private boolean encrypted = false;
+    private final AtomicBoolean encryptedOnce = new AtomicBoolean(false);
 
     public ServerConnectionImpl(@NotNull com.velocitypowered.api.proxy.ServerConnection handle) {
         this.handle = handle;
@@ -85,6 +87,16 @@ public boolean isEncrypted() {
         return encrypted;
     }
 
+    @Override
+    public void setEncryptedOnce() {
+        encryptedOnce.set(true);
+    }
+
+    @Override
+    public boolean consumeEncryptedOnce() {
+        return encryptedOnce.compareAndSet(true, false);
+    }
+
     @Override
     public @NotNull KeyPair getKeyPair() {
         return Objects.requireNonNull(keyPair);
-Original file line number
+Diff line change
@@ Expand Up / @@ -2,7 +2,6 @@ @@
     import org.jetbrains.annotations.NotNull;
-    import java.security.KeyPair;
     import java.security.PublicKey;
     /**
@@ Expand Down @@