cap dot protocol fees at 100 dot

modules/ismp/pallets/asset-gateway/src/xcm_utilities.rs

@@ -1,7 +1,7 @@
 use crate::{AssetIds, Config, Pallet};
 use alloc::vec::Vec;
 use codec::Encode;
-use core::marker::PhantomData;
+use core::{cmp::min, marker::PhantomData};
 use frame_support::traits::{
 	fungibles::{self, Mutate},
 	Contains,
@@ -200,7 +200,9 @@ where
 			// messages
 			let base_fee =
 				if who.dest_state_machine == StateMachine::Evm(1) { 20_000_000_000u128 } else { 0 };
-			let protocol_fees = protocol_percentage * u128::from(amount) + base_fee;
+			// Cap protocol fees at 100 DOT
+			let protocol_fees =
+				min(protocol_percentage * u128::from(amount) + base_fee, 1000_000_000_000u128);
 			let remainder = u128::from(amount)
 				.checked_sub(protocol_fees.into())
 				.ok_or_else(|| XcmError::Overflow)?