adjust fee to decimals by genesis and properly charge it before bumping nonce

Cargo.lock

@@ -2794,6 +2794,15 @@ dependencies = [
  "substrate-api-client",
 ]
 
+[[package]]
+name = "ita-parentchain-specs"
+version = "0.1.0"
+dependencies = [
+ "hex",
+ "itp-types",
+ "log 0.4.20",
+]
+
 [[package]]
 name = "ita-sgx-runtime"
 version = "0.9.0"
@@ -2826,6 +2835,7 @@ dependencies = [
  "base58",
  "frame-support",
  "frame-system",
+ "ita-parentchain-specs",
  "ita-sgx-runtime",
  "itp-hashing",
  "itp-node-api",

Cargo.toml

@@ -3,6 +3,7 @@ resolver = "2"
 members = [
     "app-libs/oracle",
     "app-libs/parentchain-interface",
+    "app-libs/parentchain-specs",
     "app-libs/sgx-runtime",
     "app-libs/sgx-runtime/pallets/parentchain",
     "app-libs/sgx-runtime/pallets/guess-the-number",

app-libs/parentchain-specs/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "ita-parentchain-specs"
+version = "0.1.0"
+authors = ["Integritee AG <[email protected]>"]
+edition = "2021"
+
+[dependencies]
+hex = { version = "0.4.3", default-features = false, features = ["alloc"] }
+itp-types = { path = "../../core-primitives/types", default-features = false }
+log = { version = "0.4", default-features = false }
+
+[features]
+default = ["std"]
+std = [
+    "hex/std",
+    "log/std",
+]

app-libs/parentchain-specs/src/lib.rs

@@ -0,0 +1,56 @@
+/*
+	Copyright 2021 Integritee AG
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+
+		http://www.apache.org/licenses/LICENSE-2.0
+
+	Unless required by applicable law or agreed to in writing, software
+	distributed under the License is distributed on an "AS IS" BASIS,
+	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+	See the License for the specific language governing permissions and
+	limitations under the License.
+
+*/
+// chain specs which can't be derived from chain state trustlessly by the light client
+// we hardcode them here so they can't be changed by an adversarial enclave operator
+
+#![cfg_attr(all(not(target_env = "sgx"), not(feature = "std")), no_std)]
+#![cfg_attr(target_env = "sgx", feature(rustc_private))]
+use itp_types::parentchain::{Balance, Hash};
+use log::warn;
+
+const PASEO_RELAY_GENESIS_HASH_HEX: &str =
+	"77afd6190f1554ad45fd0d31aee62aacc33c6db0ea801129acb813f913e0764f";
+const INTEGRITEE_PASEO_GENESIS_HASH_HEX: &str =
+	"1b69c462cd7dfea0e855c2008b66490cc8bbe90bc80b297ec0896a1c0941ce15";
+const INTEGRITEE_KUSAMA_GENESIS_HASH_HEX: &str =
+	"cdedc8eadbfa209d3f207bba541e57c3c58a667b05a2e1d1e86353c9000758da";
+
+/// modify this for testing if necessary
+const LOCAL_TEST_GENESIS_HASH_HEX: &str =
+	"6ca6d29ad6c4a200c4af356f74f03d6467dbc8a6e9ef225a2e672a990e1c7ead";
+pub struct MinimalChainSpec {}
+
+impl MinimalChainSpec {
+	pub fn decimals(genesis_hash: Hash) -> u8 {
+		let genesis_hash_hex = hex::encode(genesis_hash);
+		match genesis_hash_hex.as_ref() {
+			PASEO_RELAY_GENESIS_HASH_HEX => 10,
+			INTEGRITEE_PASEO_GENESIS_HASH_HEX | INTEGRITEE_KUSAMA_GENESIS_HASH_HEX => 12,
+			LOCAL_TEST_GENESIS_HASH_HEX => 10,
+			_ => {
+				warn!(
+					"parentchain spec for genesis {} unknown. defaulting to 12 decimals",
+					genesis_hash_hex
+				);
+				12
+			},
+		}
+	}
+	pub fn one_unit(genesis_hash: Hash) -> Balance {
+		10u128.pow(Self::decimals(genesis_hash) as u32)
+	}
+}

app-libs/stf/Cargo.toml

@@ -15,6 +15,7 @@ sha3 = { version = "0.10", default-features = false }
 sgx_tstd = { branch = "master", features = ["untrusted_fs", "net", "backtrace"], git = "https://github.com/apache/teaclave-sgx-sdk.git", optional = true }
 
 # local crates
+ita-parentchain-specs = { default-features = false, path = "../parentchain-specs" }
 ita-sgx-runtime = { default-features = false, path = "../sgx-runtime" }
 itp-hashing = { default-features = false, path = "../../core-primitives/hashing" }
 itp-node-api = { default-features = false, path = "../../core-primitives/node-api" }
@@ -61,6 +62,7 @@ std = [
     "rlp/std",
     # local
     "ita-sgx-runtime/std",
+    "ita-parentchain-specs/std",
     "itp-hashing/std",
     "itp-sgx-externalities/std",
     "itp-stf-interface/std",

app-libs/stf/src/getter.rs

@@ -38,7 +38,7 @@ use crate::evm_helpers::{get_evm_account, get_evm_account_codes, get_evm_account
 
 use crate::{
 	guess_the_number::{GuessTheNumberPublicGetter, GuessTheNumberTrustedGetter},
-	helpers::{shard_vault, wrap_bytes},
+	helpers::{shielding_target, wrap_bytes},
 };
 use itp_sgx_runtime_primitives::types::Moment;
 use itp_stf_primitives::traits::PoolTransactionValidation;
@@ -272,9 +272,7 @@ impl ExecuteGetter for PublicGetter {
 					integritee,
 					target_a,
 					target_b,
-					shielding_target: shard_vault()
-						.map(|v| v.1)
-						.unwrap_or(ParentchainId::Integritee),
+					shielding_target: shielding_target(),
 				};
 				Some(parentchains_info.encode())
 			},

app-libs/stf/src/guess_the_number.rs

@@ -1,8 +1,28 @@
-use crate::helpers::enclave_signer_account;
+/*
+	Copyright 2021 Integritee AG and Supercomputing Systems AG
+
+	Licensed under the Apache License, Version 2.0 (the "License");
+	you may not use this file except in compliance with the License.
+	You may obtain a copy of the License at
+
+		http://www.apache.org/licenses/LICENSE-2.0
+
+	Unless required by applicable law or agreed to in writing, software
+	distributed under the License is distributed on an "AS IS" BASIS,
+	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+	See the License for the specific language governing permissions and
+	limitations under the License.
+
+*/
+
+// TrustedCalls and Getters for the Guess-The-Number game
+
+use crate::helpers::shielding_target_genesis_hash;
 #[cfg(not(feature = "std"))]
 use alloc::format;
 use codec::{Decode, Encode};
 use frame_support::dispatch::UnfilteredDispatchable;
+use ita_parentchain_specs::MinimalChainSpec;
 use ita_sgx_runtime::{GuessTheNumber, GuessType, Runtime, System};
 use itp_node_api::metadata::provider::AccessNodeMetadata;
 use itp_node_api_metadata::NodeMetadataTrait;
@@ -11,8 +31,7 @@ use itp_stf_interface::{ExecuteCall, ExecuteGetter};
 use itp_stf_primitives::error::StfError;
 use itp_types::{parentchain::ParentchainCall, AccountId};
 use itp_utils::stringify::account_id_to_string;
-use log::{debug, info, trace};
-use sp_runtime::MultiAddress;
+use log::*;
 use sp_std::{sync::Arc, vec::Vec};
 
 /// General public information about the status of the guess-the-number game
@@ -98,20 +117,6 @@ where
 			Self::guess(sender, guess) => {
 				let origin = ita_sgx_runtime::RuntimeOrigin::signed(sender);
 				std::println!("⣿STF⣿ guess-the-number: someone is attempting a guess");
-				// endow fee to enclave (self)
-				let fee_recipient: itp_stf_primitives::types::AccountId = enclave_signer_account();
-				// fixme: apply fees through standard frame process and tune it
-				let fee = crate::STF_GUESS_FEE;
-				info!("guess fee {}", fee);
-				ita_sgx_runtime::BalancesCall::<Runtime>::transfer {
-					dest: MultiAddress::Id(fee_recipient),
-					value: fee,
-				}
-				.dispatch_bypass_filter(origin.clone())
-				.map_err(|e| {
-					Self::Error::Dispatch(format!("GuessTheNumber fee error: {:?}", e.error))
-				})?;
-
 				ita_sgx_runtime::GuessTheNumberCall::<Runtime>::guess { guess }
 					.dispatch_bypass_filter(origin)
 					.map_err(|e| {
@@ -129,6 +134,14 @@ where
 	}
 }
 
+pub fn get_fee_for(tc: &GuessTheNumberTrustedCall) -> Balance {
+	let one = MinimalChainSpec::one_unit(shielding_target_genesis_hash().unwrap_or_default());
+	match tc {
+		GuessTheNumberTrustedCall::guess(..) => one / crate::STF_GUESS_FEE_UNIT_DIVIDER,
+		_ => Balance::from(0u32),
+	}
+}
+
 #[derive(Encode, Decode, Clone, Debug, PartialEq, Eq)]
 #[allow(non_camel_case_types)]
 pub enum GuessTheNumberPublicGetter {

app-libs/stf/src/helpers.rs

@@ -23,7 +23,7 @@ use itp_stf_primitives::{
 	types::AccountId,
 };
 use itp_storage::{storage_double_map_key, storage_map_key, storage_value_key, StorageHasher};
-use itp_types::parentchain::ParentchainId;
+use itp_types::parentchain::{Hash, ParentchainId};
 use itp_utils::stringify::account_id_to_string;
 use log::*;
 use std::prelude::v1::*;
@@ -116,6 +116,20 @@ pub fn shard_vault() -> Option<(AccountId, ParentchainId)> {
 	get_shard_vaults().into_iter().next()
 }
 
+/// get shielding target from parentchain pallets
+pub fn shielding_target() -> ParentchainId {
+	shard_vault().map(|v| v.1).unwrap_or(ParentchainId::Integritee)
+}
+
+/// get genesis hash of shielding target parentchain, if available
+pub fn shielding_target_genesis_hash() -> Option<Hash> {
+	match shielding_target() {
+		ParentchainId::Integritee => ParentchainIntegritee::parentchain_genesis_hash(),
+		ParentchainId::TargetA => ParentchainTargetA::parentchain_genesis_hash(),
+		ParentchainId::TargetB => ParentchainTargetB::parentchain_genesis_hash(),
+	}
+}
+
 /// We assume it has been ensured elsewhere that there can't be multiple shard vaults on multiple parentchains
 pub fn get_shard_vaults() -> Vec<(AccountId, ParentchainId)> {
 	[

app-libs/stf/src/lib.rs

@@ -47,8 +47,6 @@ pub mod test_genesis;
 pub mod trusted_call;
 
 pub(crate) const ENCLAVE_ACCOUNT_KEY: &str = "Enclave_Account_Key";
-
-// fixme: this if a temporary hack only. double-check decimals for target chain
-// as long as it is hard-coded, needs to be reasonable for 10 (Paseo) and 12 decimals
-pub const STF_TX_FEE: Balance = 100_000_000;
-pub const STF_GUESS_FEE: Balance = 10_000_000_000;
+pub const STF_SHIELDING_FEE_AMOUNT_DIVIDER: Balance = 571; // approx 0.175%
+pub const STF_TX_FEE_UNIT_DIVIDER: Balance = 100; // 0.01 tokens
+pub const STF_GUESS_FEE_UNIT_DIVIDER: Balance = 10; // 0.1 tokens

app-libs/stf/src/trusted_call.rs

@@ -25,11 +25,15 @@ use std::vec::Vec;
 use crate::evm_helpers::{create_code_hash, evm_create2_address, evm_create_address};
 use crate::{
 	guess_the_number::GuessTheNumberTrustedCall,
-	helpers::{enclave_signer_account, ensure_enclave_signer_account, shard_vault, wrap_bytes},
-	Getter,
+	helpers::{
+		enclave_signer_account, ensure_enclave_signer_account, shard_vault,
+		shielding_target_genesis_hash, wrap_bytes,
+	},
+	Getter, STF_SHIELDING_FEE_AMOUNT_DIVIDER,
 };
 use codec::{Compact, Decode, Encode};
 use frame_support::{ensure, traits::UnfilteredDispatchable};
+use ita_parentchain_specs::MinimalChainSpec;
 #[cfg(feature = "evm")]
 use ita_sgx_runtime::{AddressMapping, HashedAddressMapping};
 pub use ita_sgx_runtime::{Balance, Index};
@@ -244,6 +248,10 @@ where
 		let system_nonce = System::account_nonce(&sender);
 		ensure!(self.nonce == system_nonce, Self::Error::InvalidNonce(self.nonce, system_nonce));
 
+		// try to charge fee first and fail early
+		let fee = get_fee_for(&self);
+		charge_fee(fee, &sender)?;
+
 		// increment the nonce, no matter if the call succeeds or fails.
 		// The call must have entered the transaction pool already,
 		// so it should be considered as valid
@@ -281,27 +289,8 @@ where
 				Ok::<(), Self::Error>(())
 			},
 			TrustedCall::balance_transfer(from, to, value) => {
-				let origin = ita_sgx_runtime::RuntimeOrigin::signed(from.clone());
+				let origin = ita_sgx_runtime::RuntimeOrigin::signed(from);
 				std::println!("⣿STF⣿ 🔄 balance_transfer from ⣿⣿⣿ to ⣿⣿⣿ amount ⣿⣿⣿");
-				// endow fee to enclave (self)
-				let fee_recipient: AccountId = enclave_signer_account();
-				// fixme: apply fees through standard frame process and tune it
-				let fee = crate::STF_TX_FEE;
-				info!(
-					"from {}, to {}, amount {}, fee {}",
-					account_id_to_string(&from),
-					account_id_to_string(&to),
-					value,
-					fee
-				);
-				ita_sgx_runtime::BalancesCall::<Runtime>::transfer {
-					dest: MultiAddress::Id(fee_recipient),
-					value: fee,
-				}
-				.dispatch_bypass_filter(origin.clone())
-				.map_err(|e| {
-					Self::Error::Dispatch(format!("Balance Transfer error: {:?}", e.error))
-				})?;
 				ita_sgx_runtime::BalancesCall::<Runtime>::transfer {
 					dest: MultiAddress::Id(to),
 					value,
@@ -318,11 +307,6 @@ where
 					account_id_to_string(&beneficiary),
 					value
 				);
-				// endow fee to enclave (self)
-				let fee_recipient: AccountId = enclave_signer_account();
-				// fixme: apply fees through standard frame process and tune it. has to be at least two L1 transfer's fees
-				let fee = crate::STF_TX_FEE * 3;
-
 				info!(
 					"balance_unshield(from (L2): {}, to (L1): {}, amount {} (+fee: {}), shard {})",
 					account_id_to_string(&account_incognito),
@@ -332,15 +316,6 @@ where
 					shard
 				);
 
-				let origin = ita_sgx_runtime::RuntimeOrigin::signed(account_incognito.clone());
-				ita_sgx_runtime::BalancesCall::<Runtime>::transfer {
-					dest: MultiAddress::Id(fee_recipient),
-					value: fee,
-				}
-				.dispatch_bypass_filter(origin)
-				.map_err(|e| {
-					Self::Error::Dispatch(format!("Balance Unshielding error: {:?}", e.error))
-				})?;
 				burn_funds(account_incognito, value)?;
 
 				let (vault, parentchain_id) = shard_vault().ok_or_else(|| {
@@ -593,6 +568,29 @@ where
 	}
 }
 
+fn get_fee_for(tc: &TrustedCallSigned) -> Balance {
+	let one = MinimalChainSpec::one_unit(shielding_target_genesis_hash().unwrap_or_default());
+	match &tc.call {
+		TrustedCall::balance_transfer(..) => one / crate::STF_TX_FEE_UNIT_DIVIDER,
+		TrustedCall::balance_unshield(..) => one / crate::STF_TX_FEE_UNIT_DIVIDER * 3,
+		TrustedCall::guess_the_number(call) => crate::guess_the_number::get_fee_for(call),
+		_ => Balance::from(0u32),
+	}
+}
+
+fn charge_fee(fee: Balance, payer: &AccountId) -> Result<(), StfError> {
+	debug!("attempting to charge fee for TrustedCall");
+	let fee_recipient: AccountId = enclave_signer_account();
+	let origin = ita_sgx_runtime::RuntimeOrigin::signed(payer.clone());
+	ita_sgx_runtime::BalancesCall::<Runtime>::transfer {
+		dest: MultiAddress::Id(fee_recipient),
+		value: fee,
+	}
+	.dispatch_bypass_filter(origin)
+	.map_err(|e| StfError::Dispatch(format!("Fee Payment Error: {:?}", e.error)))?;
+	Ok(())
+}
+
 fn burn_funds(account: AccountId, amount: u128) -> Result<(), StfError> {
 	let account_info = System::account(&account);
 	if account_info.data.free < amount {
@@ -610,7 +608,7 @@ fn burn_funds(account: AccountId, amount: u128) -> Result<(), StfError> {
 
 fn shield_funds(account: AccountId, amount: u128) -> Result<(), StfError> {
 	//fixme: make fee configurable and send fee to vault account on L2
-	let fee = amount / 571; // approx 0.175%
+	let fee = amount / STF_SHIELDING_FEE_AMOUNT_DIVIDER;
 
 	// endow fee to enclave (self)
 	let fee_recipient: AccountId = enclave_signer_account();

cli/demo_shielding_unshielding.sh

@@ -67,7 +67,7 @@ echo ""
 
 # the parentchain token is 12 decimal
 UNIT=$(( 10 ** 12 ))
-FEE_TOLERANCE=$((10 ** 11))
+FEE_TOLERANCE=$((2 * 10 ** 11))
 
 # make these amounts greater than ED
 AMOUNT_SHIELD=$(( 6 * UNIT ))