Merge pull request #99 from lucko/feature/command-permissions

Implement optional permission check method for commands

api/src/main/java/com/velocitypowered/api/command/Command.java

@@ -26,4 +26,19 @@ public interface Command {
     default List<String> suggest(@NonNull CommandSource source, @NonNull String[] currentArgs) {
         return ImmutableList.of();
     }
+
+    /**
+     * Tests to check if the {@code source} has permission to use this command
+     * with the provided {@code args}.
+     *
+     * <p>If this method returns false, the handling will be forwarded onto
+     * the players current server.</p>
+     *
+     * @param source the source of the command
+     * @param args the arguments for this command
+     * @return whether the source has permission
+     */
+    default boolean hasPermission(@NonNull CommandSource source, @NonNull String[] args) {
+        return true;
+    }
 }

api/src/main/java/com/velocitypowered/api/permission/PermissionFunction.java

@@ -29,5 +29,5 @@ public interface PermissionFunction {
      * @param permission the permission
      * @return the value the permission is set to
      */
-    @NonNull Tristate getPermissionSetting(@NonNull String permission);
+    @NonNull Tristate getPermissionValue(@NonNull String permission);
 }

api/src/main/java/com/velocitypowered/api/permission/PermissionSubject.java

@@ -12,5 +12,15 @@ public interface PermissionSubject {
      * @param permission the permission to check for
      * @return whether or not the subject has the permission
      */
-    boolean hasPermission(@NonNull String permission);
+    default boolean hasPermission(@NonNull String permission) {
+        return getPermissionValue(permission).asBoolean();
+    }
+
+    /**
+     * Gets the subjects setting for a particular permission.
+     *
+     * @param permission the permission
+     * @return the value the permission is set to
+     */
+    @NonNull Tristate getPermissionValue(@NonNull String permission);
 }

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -8,6 +8,7 @@ import com.velocitypowered.api.command.CommandSource;
 import com.velocitypowered.api.event.EventManager;
 import com.velocitypowered.api.event.proxy.ProxyInitializeEvent;
 import com.velocitypowered.api.event.proxy.ProxyShutdownEvent;
+import com.velocitypowered.api.permission.Tristate;
 import com.velocitypowered.api.plugin.PluginManager;
 import com.velocitypowered.api.proxy.Player;
 import com.velocitypowered.api.proxy.ProxyServer;
@@ -40,6 +41,7 @@ import net.kyori.text.serializer.ComponentSerializers;
 import net.kyori.text.serializer.GsonComponentSerializer;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.checkerframework.checker.nullness.qual.NonNull;
 
 import java.net.InetSocketAddress;
 import java.nio.file.Files;
@@ -78,8 +80,8 @@ public class VelocityServer implements ProxyServer {
         }
 
         @Override
-        public boolean hasPermission(String permission) {
-            return true;
+        public @NonNull Tristate getPermissionValue(@NonNull String permission) {
+            return Tristate.TRUE;
         }
     };
     private Ratelimiter ipAttemptLimiter;

proxy/src/main/java/com/velocitypowered/proxy/command/ServerCommand.java

@@ -3,6 +3,7 @@ package com.velocitypowered.proxy.command;
 import com.google.common.collect.ImmutableList;
 import com.velocitypowered.api.command.Command;
 import com.velocitypowered.api.command.CommandSource;
+import com.velocitypowered.api.permission.Tristate;
 import com.velocitypowered.api.proxy.Player;
 import com.velocitypowered.api.proxy.ProxyServer;
 import com.velocitypowered.api.proxy.ServerConnection;
@@ -12,6 +13,7 @@ import net.kyori.text.TextComponent;
 import net.kyori.text.event.ClickEvent;
 import net.kyori.text.event.HoverEvent;
 import net.kyori.text.format.TextColor;
+import org.checkerframework.checker.nullness.qual.NonNull;
 
 import java.util.List;
 import java.util.Optional;
@@ -88,4 +90,9 @@ public class ServerCommand implements Command {
             return ImmutableList.of();
         }
     }
+
+    @Override
+    public boolean hasPermission(@NonNull CommandSource source, @NonNull String[] args) {
+        return source.getPermissionValue("velocity.command.server") != Tristate.FALSE;
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/command/ShutdownCommand.java

@@ -5,6 +5,7 @@ import com.velocitypowered.api.command.CommandSource;
 import com.velocitypowered.proxy.VelocityServer;
 import net.kyori.text.TextComponent;
 import net.kyori.text.format.TextColor;
+import org.checkerframework.checker.nullness.qual.NonNull;
 
 public class ShutdownCommand implements Command {
     private final VelocityServer server;
@@ -21,4 +22,9 @@ public class ShutdownCommand implements Command {
         }
         server.shutdown();
     }
+
+    @Override
+    public boolean hasPermission(@NonNull CommandSource source, @NonNull String[] args) {
+        return source == server.getConsoleCommandSource();
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/command/VelocityCommand.java

@@ -2,10 +2,12 @@ package com.velocitypowered.proxy.command;
 
 import com.velocitypowered.api.command.Command;
 import com.velocitypowered.api.command.CommandSource;
+import com.velocitypowered.api.permission.Tristate;
 import com.velocitypowered.proxy.VelocityServer;
 import net.kyori.text.TextComponent;
 import net.kyori.text.event.ClickEvent;
 import net.kyori.text.format.TextColor;
+import org.checkerframework.checker.nullness.qual.NonNull;
 
 public class VelocityCommand implements Command {
     @Override
@@ -37,4 +39,9 @@ public class VelocityCommand implements Command {
         source.sendMessage(velocityInfo);
         source.sendMessage(velocityWebsite);
     }
+
+    @Override
+    public boolean hasPermission(@NonNull CommandSource source, @NonNull String[] args) {
+        return source.getPermissionValue("velocity.command.info") != Tristate.FALSE;
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/command/VelocityCommandManager.java

@@ -46,6 +46,10 @@ public class VelocityCommandManager implements CommandManager {
         }
 
         try {
+            if (!command.hasPermission(source, actualArgs)) {
+                return false;
+            }
+
             command.execute(source, actualArgs);
             return true;
         } catch (Exception e) {
@@ -62,24 +66,29 @@ public class VelocityCommandManager implements CommandManager {
             return Optional.empty();
         }
 
-        String command = split[0];
+        String alias = split[0];
         if (split.length == 1) {
-            return Optional.of(commands.keySet().stream()
-                    .filter(cmd -> cmd.regionMatches(true, 0, command, 0, command.length()))
-                    .map(cmd -> "/" + cmd)
+            return Optional.of(commands.entrySet().stream()
+                    .filter(ent -> ent.getKey().regionMatches(true, 0, alias, 0, alias.length()))
+                    .filter(ent -> ent.getValue().hasPermission(source, new String[0]))
+                    .map(ent -> "/" + ent.getKey())
                     .collect(Collectors.toList()));
         }
 
         String[] actualArgs = Arrays.copyOfRange(split, 1, split.length);
-        Command executor = commands.get(command);
-        if (executor == null) {
+        Command command = commands.get(alias.toLowerCase(Locale.ENGLISH));
+        if (command == null) {
             return Optional.empty();
         }
 
         try {
-            return Optional.of(executor.suggest(source, actualArgs));
+            if (!command.hasPermission(source, actualArgs)) {
+                return Optional.empty();
+            }
+
+            return Optional.of(command.suggest(source, actualArgs));
         } catch (Exception e) {
-            throw new RuntimeException("Unable to invoke suggestions for command " + command + " for " + source, e);
+            throw new RuntimeException("Unable to invoke suggestions for command " + alias + " for " + source, e);
         }
     }
 }

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ConnectedPlayer.java

@@ -7,6 +7,7 @@ import com.velocitypowered.api.event.player.PlayerSettingsChangedEvent;
 import com.velocitypowered.api.event.player.ServerPreConnectEvent;
 import com.velocitypowered.api.permission.PermissionFunction;
 import com.velocitypowered.api.permission.PermissionProvider;
+import com.velocitypowered.api.permission.Tristate;
 import com.velocitypowered.api.proxy.ConnectionRequestBuilder;
 import com.velocitypowered.api.proxy.Player;
 import com.velocitypowered.api.proxy.ServerConnection;
@@ -390,8 +391,8 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
     }
 
     @Override
-    public boolean hasPermission(String permission) {
-        return permissionFunction.getPermissionSetting(permission).asBoolean();
+    public @NonNull Tristate getPermissionValue(@NonNull String permission) {
+        return permissionFunction.getPermissionValue(permission);
     }
 
     @Override