Stop people creating nether portals in claimed land

src/main/java/me/ryanhamshire/GriefPrevention/BlockEventHandler.java

@@ -64,6 +64,7 @@
 import org.bukkit.event.entity.ProjectileHitEvent;
 import org.bukkit.event.hanging.HangingBreakEvent;
 import org.bukkit.event.inventory.InventoryPickupItemEvent;
+import org.bukkit.event.world.PortalCreateEvent;
 import org.bukkit.event.world.StructureGrowEvent;
 import org.bukkit.inventory.InventoryHolder;
 import org.bukkit.inventory.ItemStack;
@@ -1077,4 +1078,45 @@ public void onItemFrameBrokenByBoat(final HangingBreakEvent event)
             event.setCancelled(true);
         }
     }
+
+
+    @EventHandler(ignoreCancelled = true)
+    public void onNetherPortalCreate(final PortalCreateEvent event)
+    {
+        if (event.getReason() != PortalCreateEvent.CreateReason.NETHER_PAIR)
+        {
+            return;
+        }
+
+        // Ignore this event if preventNonPlayerCreatedPortals config option is disabled, and we don't know the entity.
+        if (!(event.getEntity() instanceof Player) && !GriefPrevention.instance.config_claims_preventNonPlayerCreatedPortals)
+        {
+            return;
+        }
+
+        for (BlockState blockState : event.getBlocks())
+        {
+            Claim claim = this.dataStore.getClaimAt(blockState.getLocation(), false, null);
+            if (claim != null)
+            {
+                if (event.getEntity() instanceof Player player)
+                {
+                    Supplier<String> noPortalReason = claim.checkPermission(player, ClaimPermission.Build, event);
+
+                    if (noPortalReason != null)
+                    {
+                        event.setCancelled(true);
+                        GriefPrevention.sendMessage(player, TextMode.Err, noPortalReason.get());
+                        return;
+                    }
+                }
+                else
+                {
+                    // Cancels the event if in a claim, as we can not efficiently retrieve the person/entity who created the portal.
+                    event.setCancelled(true);
+                    return;
+                }
+            }
+        }
+    }
 }

src/main/java/me/ryanhamshire/GriefPrevention/GriefPrevention.java

@@ -108,6 +108,7 @@ public class GriefPrevention extends JavaPlugin
     public boolean config_claims_lockWoodenDoors;                    //whether wooden doors should be locked by default (require /accesstrust)
     public boolean config_claims_lockTrapDoors;                        //whether trap doors should be locked by default (require /accesstrust)
     public boolean config_claims_lockFenceGates;                    //whether fence gates should be locked by default (require /accesstrust)
+    public boolean config_claims_preventNonPlayerCreatedPortals;    // whether portals where we cannot determine the creating player should be prevented from creation in claims
     public boolean config_claims_enderPearlsRequireAccessTrust;        //whether teleporting into a claim with a pearl requires access trust
     public boolean config_claims_raidTriggersRequireBuildTrust;      //whether raids are triggered by a player that doesn't have build permission in that claim
     public int config_claims_maxClaimsPerPlayer;                    //maximum number of claims per player
@@ -541,6 +542,7 @@ else if (world.getEnvironment() == Environment.NORMAL)
         this.config_claims_lockWoodenDoors = config.getBoolean("GriefPrevention.Claims.LockWoodenDoors", false);
         this.config_claims_lockTrapDoors = config.getBoolean("GriefPrevention.Claims.LockTrapDoors", false);
         this.config_claims_lockFenceGates = config.getBoolean("GriefPrevention.Claims.LockFenceGates", true);
+        this.config_claims_preventNonPlayerCreatedPortals = config.getBoolean("GriefPrevention.Claims.PreventNonPlayerCreatedPortals", false);
         this.config_claims_enderPearlsRequireAccessTrust = config.getBoolean("GriefPrevention.Claims.EnderPearlsRequireAccessTrust", true);
         this.config_claims_raidTriggersRequireBuildTrust = config.getBoolean("GriefPrevention.Claims.RaidTriggersRequireBuildTrust", true);
         this.config_claims_initialBlocks = config.getInt("GriefPrevention.Claims.InitialBlocks", 100);