feat(l2): add oracle for fee tokens transactions

cmd/ethrex/build_l2.rs

@@ -129,6 +129,10 @@ pub fn download_script() {
             &Path::new("../../crates/l2/contracts/src/l2/FeeTokenRegistry.sol"),
             "FeeTokenRegistry",
         ),
+        (
+            &Path::new("../../crates/l2/contracts/src/l2/FeeTokenPricer.sol"),
+            "FeeTokenPricer",
+        ),
     ];
     for (path, name) in l2_contracts {
         compile_contract_to_bytecode(
@@ -277,8 +281,8 @@ fn decode_to_bytecode(input_file_path: &Path, output_file_path: &Path) {
 
 use ethrex_l2_sdk::{
     COMMON_BRIDGE_L2_ADDRESS, CREATE2DEPLOYER_ADDRESS, DETERMINISTIC_DEPLOYMENT_PROXY_ADDRESS,
-    FEE_TOKEN_REGISTRY_ADDRESS, L2_TO_L1_MESSENGER_ADDRESS, SAFE_SINGLETON_FACTORY_ADDRESS,
-    address_to_word, get_erc1967_slot,
+    FEE_TOKEN_PRICER_ADDRESS, FEE_TOKEN_REGISTRY_ADDRESS, L2_TO_L1_MESSENGER_ADDRESS,
+    SAFE_SINGLETON_FACTORY_ADDRESS, address_to_word, get_erc1967_slot,
 };
 
 #[allow(clippy::enum_variant_names)]
@@ -341,6 +345,12 @@ fn fee_token_registry_runtime(out_dir: &Path) -> Vec<u8> {
     fs::read(path).expect("Failed to read bytecode file")
 }
 
+/// Bytecode of the FeeTokenPricer contract.
+fn fee_token_pricer_runtime(out_dir: &Path) -> Vec<u8> {
+    let path = out_dir.join("contracts/solc_out/FeeTokenPricer.bytecode");
+    fs::read(path).expect("Failed to read bytecode file")
+}
+
 /// Bytecode of the Create2Deployer contract.
 fn create2deployer_runtime(out_dir: &Path) -> Vec<u8> {
     let path = out_dir.join("contracts/solc_out/Create2Deployer.bytecode");
@@ -451,7 +461,14 @@ pub fn update_genesis_file(
         out_dir,
     )?;
 
-    for address in 0xff00..0xfffb {
+    add_with_proxy(
+        &mut genesis,
+        FEE_TOKEN_PRICER_ADDRESS,
+        fee_token_pricer_runtime(out_dir),
+        out_dir,
+    )?;
+
+    for address in 0xff00..0xfffa {
         add_placeholder_proxy(&mut genesis, Address::from_low_u64_be(address), out_dir)?;
     }
 

crates/l2/contracts/src/l2/FeeTokenPricer.sol

@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: MIT
+pragma solidity =0.8.29;
+import "./interfaces/IFeeTokenPricer.sol";
+
+contract FeeTokenPricer is IFeeTokenPricer {  
+	address internal constant FEE_TOKEN =
+        0xb7E811662Fa10ac068aeE115AC2e682821630535;
+
+	  /// @inheritdoc IFeeTokenPricer
+		function getFeeTokenRatio(
+			  address fee_token
+		) external view override returns (uint256) {
+			require(fee_token == FEE_TOKEN, "The fee token does not match with the one set for the chain");
+			return 2;
+		}	
+}

crates/l2/contracts/src/l2/interfaces/IFeeTokenPricer.sol

@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: MIT
+pragma solidity =0.8.29;
+
+/// @title IFeeTokenPricer
+/// @notice Interface for a contract that provides pricing information for fee tokens.
+interface IFeeTokenPricer {
+    /// @notice Returns the ratio of fee token (implements FeeToken) to ETH in wei.
+    /// @param feeToken The address of the fee token.
+    /// @return ratio The amount of fee token (in its smallest unit) equivalent to 1 wei.
+    function getFeeTokenRatio(address feeToken) external view returns (uint256);
+}

crates/l2/sdk/src/sdk.rs

@@ -62,6 +62,12 @@ pub const FEE_TOKEN_REGISTRY_ADDRESS: Address = H160([
     0x00, 0x00, 0xff, 0xfc,
 ]);
 
+// 0x000000000000000000000000000000000000fffb
+pub const FEE_TOKEN_PRICER_ADDRESS: Address = H160([
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xff, 0xfb,
+]);
+
 // 0xee110000000000000000000000000000000011ff
 pub const ADDRESS_ALIASING: Address = H160([
     0xee, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -1114,3 +1120,26 @@ async fn _call_bytes32_variable(
 
     Ok(arr)
 }
+
+pub async fn get_fee_token_ratio(
+    fee_token: &Address,
+    client: &EthClient,
+) -> Result<u64, EthClientError> {
+    let values = vec![Value::Address(*fee_token)];
+    let calldata = encode_calldata("getFeeTokenRatio(address)", &values)?;
+
+    let ratio = client
+        .call(
+            FEE_TOKEN_PRICER_ADDRESS,
+            calldata.into(),
+            Default::default(),
+        )
+        .await?;
+
+    let ratio: u64 = ratio
+        .trim_start_matches("0x")
+        .parse::<u64>()
+        .map_err(|e| EthClientError::Custom(format!("Failed to parse ratio to u64: {}", e)))?;
+
+    Ok(ratio)
+}

crates/l2/tests/tests.rs

@@ -24,7 +24,8 @@ use ethrex_l2_sdk::{
     wait_for_transaction_receipt,
 };
 use ethrex_l2_sdk::{
-    build_generic_tx, get_last_verified_batch, send_generic_transaction, wait_for_message_proof,
+    build_generic_tx, get_fee_token_ratio, get_last_verified_batch, send_generic_transaction,
+    wait_for_message_proof,
 };
 use ethrex_rpc::{
     clients::eth::{EthClient, Overrides},
@@ -2118,13 +2119,16 @@ async fn test_fee_token(
 
     let transfer_fees =
         get_fees_details_l2(&transfer_receipt, &l2_client, get_fee_token_diff_size()).await?;
+    let fee_token_ratio = get_fee_token_ratio(&fee_token_address, &l2_client)
+        .await
+        .unwrap();
 
     let sender_fee_token_spent = sender_token_balance_before_transfer
         .checked_sub(sender_token_balance_after_transfer)
         .expect("Sender fee token balance increased unexpectedly");
     assert_eq!(
         sender_fee_token_spent,
-        U256::from(transfer_fees.total()),
+        U256::from(transfer_fees.total()) * fee_token_ratio,
         "{test}: Sender fee token spend mismatch"
     );
 
@@ -2135,7 +2139,7 @@ async fn test_fee_token(
         .expect("Coinbase fee token balance decreased");
     assert_eq!(
         coinbase_delta,
-        U256::from(transfer_fees.priority_fees),
+        U256::from(transfer_fees.priority_fees) * fee_token_ratio,
         "{test}: Priority fee mismatch"
     );
 
@@ -2150,7 +2154,7 @@ async fn test_fee_token(
             .expect("Base fee vault balance decreased");
         assert_eq!(
             base_fee_vault_delta,
-            U256::from(transfer_fees.base_fees),
+            U256::from(transfer_fees.base_fees) * fee_token_ratio,
             "{test}: Base fee vault mismatch"
         );
     }
@@ -2170,7 +2174,7 @@ async fn test_fee_token(
         .expect("Operator fee vault balance decreased");
     assert_eq!(
         operator_fee_vault_delta,
-        U256::from(transfer_fees.operator_fees),
+        U256::from(transfer_fees.operator_fees) * fee_token_ratio,
         "{test}: Operator fee vault mismatch"
     );
 
@@ -2179,7 +2183,7 @@ async fn test_fee_token(
         .expect("L1 fee vault balance decreased");
     assert_eq!(
         l1_fee_vault_delta,
-        U256::from(transfer_fees.l1_fees),
+        U256::from(transfer_fees.l1_fees) * fee_token_ratio,
         "{test}: L1 fee vault mismatch"
     );
 

crates/vm/backends/levm/mod.rs

@@ -8,6 +8,8 @@ use crate::system_contracts::{
 };
 use crate::{EvmError, ExecutionResult};
 use bytes::Bytes;
+use ethrex_common::H160;
+use ethrex_common::types::TxType;
 use ethrex_common::types::fee_config::FeeConfig;
 use ethrex_common::{
     Address, U256,
@@ -31,6 +33,12 @@ use ethrex_levm::{
 use std::cmp::min;
 use std::sync::atomic::{AtomicUsize, Ordering};
 use std::sync::mpsc::Sender;
+// getFeeTokenRatio(address feeToken) external view override returns (uint256)
+const GET_FEE_TOKEN_RATIO_SELECTOR: [u8; 4] = [0xc6, 0xab, 0x85, 0xd8];
+pub const FEE_TOKEN_RATIO_ADDRESS: Address = H160([
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xff, 0xfb,
+]);
 
 /// The struct implements the following functions:
 /// [LEVM::execute_block]
@@ -171,6 +179,13 @@ impl LEVM {
             block_header.base_fee_per_gas.unwrap_or_default(),
             &vm_type,
         )?;
+        let fee_ratio = if let Some(fee_token) = tx.fee_token()
+            && tx.tx_type() == TxType::FeeToken
+        {
+            get_fee_token_ratio(block_header, db, vm_type, chain_config, fee_token)?
+        } else {
+            None
+        };
 
         let config = EVMConfig::new_from_chain_config(&chain_config, block_header);
         let env = Environment {
@@ -195,6 +210,7 @@ impl LEVM {
             difficulty: block_header.difficulty,
             is_privileged: matches!(tx, Transaction::PrivilegedL2Transaction(_)),
             fee_token: tx.fee_token(),
+            fee_ratio,
         };
 
         Ok(env)
@@ -434,6 +450,32 @@ impl LEVM {
     }
 }
 
+fn get_fee_token_ratio(
+    block_header: &BlockHeader,
+    db: &mut GeneralizedDatabase,
+    vm_type: VMType,
+    chain_config: ethrex_common::types::ChainConfig,
+    fee_token: ethrex_common::H160,
+) -> Result<Option<U256>, EvmError> {
+    let mut data = GET_FEE_TOKEN_RATIO_SELECTOR.to_vec();
+    data.extend_from_slice(&[0u8; 12]);
+    data.extend_from_slice(fee_token.as_bytes());
+    let tx_query = EIP1559Transaction {
+        to: TxKind::Call(FEE_TOKEN_RATIO_ADDRESS),
+        chain_id: chain_config.chain_id,
+        data: Bytes::from(data),
+        gas_limit: 1_000_000,
+        ..Default::default()
+    };
+    let execution_result = LEVM::simulate_tx_from_generic(
+        &GenericTransaction::from(tx_query),
+        block_header,
+        &mut db.clone(),
+        vm_type,
+    )?;
+    Ok(Some(U256::from_big_endian(&execution_result.output())))
+}
+
 pub fn generic_system_contract_levm(
     block_header: &BlockHeader,
     calldata: Bytes,
@@ -694,6 +736,7 @@ fn env_from_generic(
         difficulty: header.difficulty,
         is_privileged: false,
         fee_token: tx.fee_token,
+        fee_ratio: None,
     })
 }
 

crates/vm/levm/src/environment.rs

@@ -39,6 +39,7 @@ pub struct Environment {
     pub block_gas_limit: u64,
     pub is_privileged: bool,
     pub fee_token: Option<Address>,
+    pub fee_ratio: Option<U256>,
 }
 
 /// This struct holds special configuration variables specific to the

crates/vm/levm/src/hooks/l2_hook.rs

@@ -139,31 +139,53 @@ fn finalize_non_privileged_execution(
 
     default_hook::delete_self_destruct_accounts(vm)?;
 
+    let fee_token_ratio = vm.env.fee_ratio.map(|ratio| ratio.as_u64()).unwrap_or(1u64);
+
     if let Some(l1_fee_config) = fee_config.l1_fee_config {
-        pay_to_l1_fee_vault(vm, l1_gas, l1_fee_config, use_fee_token)?;
+        pay_to_l1_fee_vault(
+            vm,
+            l1_gas.saturating_mul(fee_token_ratio),
+            l1_fee_config,
+            use_fee_token,
+        )?;
     }
 
     if use_fee_token {
-        refund_sender_fee_token(vm, ctx_result, gas_refunded, total_gas)?;
+        refund_sender_fee_token(vm, ctx_result, gas_refunded, total_gas, fee_token_ratio)?;
     } else {
         default_hook::refund_sender(vm, ctx_result, gas_refunded, total_gas)?;
     }
 
     pay_coinbase_l2(
         vm,
-        actual_gas_used,
+        actual_gas_used.saturating_mul(fee_token_ratio),
         &fee_config.operator_fee_config,
         use_fee_token,
     )?;
 
     if let Some(base_fee_vault) = fee_config.base_fee_vault {
-        pay_base_fee_vault(vm, actual_gas_used, base_fee_vault, use_fee_token)?;
+        pay_base_fee_vault(
+            vm,
+            actual_gas_used.saturating_mul(fee_token_ratio),
+            base_fee_vault,
+            use_fee_token,
+        )?;
     } else if use_fee_token {
-        pay_base_fee_vault(vm, actual_gas_used, Address::zero(), use_fee_token)?;
+        pay_base_fee_vault(
+            vm,
+            actual_gas_used.saturating_mul(fee_token_ratio),
+            Address::zero(),
+            use_fee_token,
+        )?;
     }
 
     if let Some(operator_fee_config) = fee_config.operator_fee_config {
-        pay_operator_fee(vm, actual_gas_used, operator_fee_config, use_fee_token)?;
+        pay_operator_fee(
+            vm,
+            actual_gas_used.saturating_mul(fee_token_ratio),
+            operator_fee_config,
+            use_fee_token,
+        )?;
     }
 
     ctx_result.gas_used = total_gas;
@@ -403,6 +425,8 @@ fn prepare_execution_fee_token(vm: &mut VM<'_>) -> Result<(), crate::errors::VME
         ));
     }
 
+    let fee_token_ratio = vm.env.fee_ratio.unwrap_or(U256::one());
+
     let sender_address = vm.env.origin;
     let sender_info = vm.db.get_account(sender_address)?.info.clone();
 
@@ -429,7 +453,7 @@ fn prepare_execution_fee_token(vm: &mut VM<'_>) -> Result<(), crate::errors::VME
     // NOT CHECKED: the blob price does not matter, fee token transactions do not support blobs
 
     // (3) INSUFFICIENT_ACCOUNT_FUNDS
-    deduct_caller_fee_token(vm, gaslimit_price_product)?;
+    deduct_caller_fee_token(vm, gaslimit_price_product.saturating_mul(fee_token_ratio))?;
 
     // (4) INSUFFICIENT_MAX_FEE_PER_GAS
     default_hook::validate_sufficient_max_fee_per_gas(vm)?;
@@ -638,6 +662,7 @@ fn refund_sender_fee_token(
     ctx_result: &mut ContextResult,
     refunded_gas: u64,
     actual_gas_used: u64,
+    fee_token_ratio: u64,
 ) -> Result<(), VMError> {
     // c. Update gas used and refunded.
     ctx_result.gas_used = actual_gas_used;
@@ -657,7 +682,11 @@ fn refund_sender_fee_token(
         .ok_or(InternalError::Overflow)?;
     let sender_address = vm.env.origin;
 
-    pay_fee_token(vm, sender_address, erc20_return_amount)?;
+    pay_fee_token(
+        vm,
+        sender_address,
+        erc20_return_amount.saturating_mul(fee_token_ratio.into()),
+    )?;
 
     Ok(())
 }

fixtures/genesis/l2.json

@@ -1,5 +1,11 @@
 {
   "alloc": {
+    "0x000000000000000000000000000000000000effb": {
+      "balance": "0x0",
+      "code": "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",
+      "nonce": "0x1",
+      "storage": {}
+    },
     "0x000000000000000000000000000000000000effc": {
       "balance": "0x0",
       "code": "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",
@@ -2037,6 +2043,7 @@
       "code": "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",
       "nonce": "0x1",
       "storage": {
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