Merge pull request #208 from propeller-heads/audit/dc/rename-selector-to-function-signature

chore: Rename selector to function signature

examples/encoding-example/main.rs

@@ -64,10 +64,10 @@ fn main() {
         .clone();
     println!(" ====== Simple swap WETH -> USDC ======");
     println!(
-        "The simple swap encoded solution should be sent to address {:?} and selector {:?} and the \
+        "The simple swap encoded solution should be sent to address {:?} with function signature {:?} and the \
-    following encoded data: {:?}",
+    following encoded swaps: {:?}",
         encoded_solution.interacting_with,
-        encoded_solution.selector,
+        encoded_solution.function_signature,
         hex::encode(encoded_solution.swaps)
     );
 
@@ -138,10 +138,10 @@ fn main() {
 
     println!(" ====== Complex split swap WETH -> USDC ======");
     println!(
-    "The complex swaps encoded solution should be sent to address {:?} and selector {:?} and the \
+        "The complex swaps encoded solution should be sent to address {:?} with function signature {:?} and the \
-    following encoded data: {:?}",
+    following encoded swaps: {:?}",
-    complex_encoded_solution.interacting_with,
+        complex_encoded_solution.interacting_with,
-    complex_encoded_solution.selector,
+        complex_encoded_solution.function_signature,
-    hex::encode(complex_encoded_solution.swaps)
+        hex::encode(complex_encoded_solution.swaps)
     );
 }

src/bin/tycho-encode.rs

@@ -106,7 +106,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let encoded = serde_json::json!({
             "swaps": format!("0x{}", hex::encode(&encoded_solutions[0].swaps)),
             "interacting_with": format!("0x{}", hex::encode(&encoded_solutions[0].interacting_with)),
-            "selector": format!("{}",&encoded_solutions[0].selector),
+            "function_signature": format!("{}",&encoded_solutions[0].function_signature),
             "n_tokens": format!("{}", &encoded_solutions[0].n_tokens),
             "permit": match encoded_solutions[0].permit.as_ref() {
         Some(permit) => {

src/encoding/evm/approvals/permit2.rs

@@ -17,7 +17,10 @@ use tycho_common::Bytes;
 
 use crate::encoding::{
     errors::EncodingError,
-    evm::utils::{biguint_to_u256, bytes_to_address, encode_input, get_client, get_runtime},
+    evm::{
+        encoding_utils::encode_input,
+        utils::{biguint_to_u256, bytes_to_address, get_client, get_runtime},
+    },
     models,
 };
 

src/encoding/evm/approvals/protocol_approvals_manager.rs

@@ -14,7 +14,10 @@ use tokio::{
 
 use crate::encoding::{
     errors::EncodingError,
-    evm::utils::{encode_input, get_client, get_runtime},
+    evm::{
+        encoding_utils::encode_input,
+        utils::{get_client, get_runtime},
+    },
 };
 
 /// A manager for checking if an approval is needed for interacting with a certain spender.

src/encoding/evm/encoding_utils.rs

@@ -4,7 +4,7 @@ use alloy::{
     primitives::U256,
     signers::{local::PrivateKeySigner, Signature, SignerSync},
 };
-use alloy_primitives::Address;
+use alloy_primitives::{Address, Keccak256};
 use alloy_sol_types::{eip712_domain, SolStruct, SolValue};
 use num_bigint::BigUint;
 use tycho_common::Bytes;
@@ -13,7 +13,6 @@ use crate::encoding::{
     errors::EncodingError,
     evm::{
         approvals::permit2::PermitSingle,
-        utils,
         utils::{biguint_to_u256, bytes_to_address},
     },
     models,
@@ -34,7 +33,7 @@ use crate::encoding::{
 /// - `splitSwapPermit2`
 ///
 /// The encoding includes handling of native asset wrapping/unwrapping, permit2 support,
-/// and proper input argument formatting based on the selector string.
+/// and proper input argument formatting based on the function signature string.
 ///
 /// # ⚠️ Important Responsibility Note
 ///
@@ -60,7 +59,7 @@ use crate::encoding::{
 /// funds.
 ///
 /// # Parameters
-/// - `encoded_solution`: The solution already encoded by Tycho, including selector and swap path.
+/// - `encoded_solution`: The solution already encoded by Tycho.
 /// - `solution`: The high-level solution including tokens, amounts, and receiver info.
 /// - `token_in_already_in_router`: Whether the input token is already present in the router.
 /// - `router_address`: The address of the Tycho Router contract.
@@ -71,8 +70,8 @@ use crate::encoding::{
 /// value, data), or an error if the inputs are invalid.
 ///
 /// # Errors
-/// - Returns `EncodingError::FatalError` if the selector is unsupported or required fields (e.g.,
+/// - Returns `EncodingError::FatalError` if the function signature is unsupported or required
-///   permit or signature) are missing.
+///   fields (e.g., permit or signature) are missing.
 pub fn encode_tycho_router_call(
     chain_id: u64,
     encoded_solution: EncodedSolution,
@@ -109,7 +108,7 @@ pub fn encode_tycho_router_call(
     };
 
     let method_calldata = if encoded_solution
-        .selector
+        .function_signature
         .contains("singleSwapPermit2")
     {
         (
@@ -128,7 +127,7 @@ pub fn encode_tycho_router_call(
         )
             .abi_encode()
     } else if encoded_solution
-        .selector
+        .function_signature
         .contains("singleSwap")
     {
         (
@@ -144,7 +143,7 @@ pub fn encode_tycho_router_call(
         )
             .abi_encode()
     } else if encoded_solution
-        .selector
+        .function_signature
         .contains("sequentialSwapPermit2")
     {
         (
@@ -163,7 +162,7 @@ pub fn encode_tycho_router_call(
         )
             .abi_encode()
     } else if encoded_solution
-        .selector
+        .function_signature
         .contains("sequentialSwap")
     {
         (
@@ -179,7 +178,7 @@ pub fn encode_tycho_router_call(
         )
             .abi_encode()
     } else if encoded_solution
-        .selector
+        .function_signature
         .contains("splitSwapPermit2")
     {
         (
@@ -199,7 +198,7 @@ pub fn encode_tycho_router_call(
         )
             .abi_encode()
     } else if encoded_solution
-        .selector
+        .function_signature
         .contains("splitSwap")
     {
         (
@@ -216,10 +215,10 @@ pub fn encode_tycho_router_call(
         )
             .abi_encode()
     } else {
-        Err(EncodingError::FatalError("Invalid selector for Tycho router".to_string()))?
+        Err(EncodingError::FatalError("Invalid function signature for Tycho router".to_string()))?
     };
 
-    let contract_interaction = utils::encode_input(&encoded_solution.selector, method_calldata);
+    let contract_interaction = encode_input(&encoded_solution.function_signature, method_calldata);
     let value = if solution.given_token == native_address {
         solution.given_amount.clone()
     } else {
@@ -257,3 +256,25 @@ pub fn sign_permit(
             EncodingError::FatalError(format!("Failed to sign permit2 approval with error: {e}"))
         })
 }
+
+/// Encodes the input data for a function call to the given function selector.
+pub fn encode_input(selector: &str, mut encoded_args: Vec<u8>) -> Vec<u8> {
+    let mut hasher = Keccak256::new();
+    hasher.update(selector.as_bytes());
+    let selector_bytes = &hasher.finalize()[..4];
+    let mut call_data = selector_bytes.to_vec();
+    // Remove extra prefix if present (32 bytes for dynamic data)
+    // Alloy encoding is including a prefix for dynamic data indicating the offset or length
+    // but at this point we don't want that
+    if encoded_args.len() > 32 &&
+        encoded_args[..32] ==
+            [0u8; 31]
+                .into_iter()
+                .chain([32].to_vec())
+                .collect::<Vec<u8>>()
+    {
+        encoded_args = encoded_args[32..].to_vec();
+    }
+    call_data.extend(encoded_args);
+    call_data
+}

src/encoding/evm/strategy_encoder/strategy_encoders.rs

@@ -23,13 +23,13 @@ use crate::encoding::{
 ///
 /// # Fields
 /// * `swap_encoder_registry`: SwapEncoderRegistry, containing all possible swap encoders
-/// * `selector`: String, the selector for the swap function in the router contract
+/// * `function_signature`: String, the signature for the swap function in the router contract
 /// * `router_address`: Address of the router to be used to execute swaps
 /// * `transfer_optimization`: TransferOptimization, responsible for optimizing the token transfers
 #[derive(Clone)]
 pub struct SingleSwapStrategyEncoder {
     swap_encoder_registry: SwapEncoderRegistry,
-    selector: String,
+    function_signature: String,
     router_address: Bytes,
     transfer_optimization: TransferOptimization,
 }
@@ -41,14 +41,14 @@ impl SingleSwapStrategyEncoder {
         user_transfer_type: UserTransferType,
         router_address: Bytes,
     ) -> Result<Self, EncodingError> {
-        let selector = if user_transfer_type == UserTransferType::TransferFromPermit2 {
+        let function_signature = if user_transfer_type == UserTransferType::TransferFromPermit2 {
             "singleSwapPermit2(uint256,address,address,uint256,bool,bool,address,((address,uint160,uint48,uint48),address,uint256),bytes,bytes)"
         } else {
             "singleSwap(uint256,address,address,uint256,bool,bool,address,bool,bytes)"
         }.to_string();
 
         Ok(Self {
-            selector,
+            function_signature,
             swap_encoder_registry,
             router_address: router_address.clone(),
             transfer_optimization: TransferOptimization::new(
@@ -133,7 +133,7 @@ impl StrategyEncoder for SingleSwapStrategyEncoder {
             grouped_protocol_data,
         );
         Ok(EncodedSolution {
-            selector: self.selector.clone(),
+            function_signature: self.function_signature.clone(),
             interacting_with: self.router_address.clone(),
             swaps: swap_data,
             permit: None,
@@ -155,7 +155,7 @@ impl StrategyEncoder for SingleSwapStrategyEncoder {
 ///
 /// # Fields
 /// * `swap_encoder_registry`: SwapEncoderRegistry, containing all possible swap encoders
-/// * `selector`: String, the selector for the swap function in the router contract
+/// * `function_signature`: String, the signature for the swap function in the router contract
 /// * `native_address`: Address of the chain's native token
 /// * `wrapped_address`: Address of the chain's wrapped token
 /// * `router_address`: Address of the router to be used to execute swaps
@@ -165,7 +165,7 @@ impl StrategyEncoder for SingleSwapStrategyEncoder {
 #[derive(Clone)]
 pub struct SequentialSwapStrategyEncoder {
     swap_encoder_registry: SwapEncoderRegistry,
-    selector: String,
+    function_signature: String,
     router_address: Bytes,
     native_address: Bytes,
     wrapped_address: Bytes,
@@ -180,14 +180,14 @@ impl SequentialSwapStrategyEncoder {
         user_transfer_type: UserTransferType,
         router_address: Bytes,
     ) -> Result<Self, EncodingError> {
-        let selector = if user_transfer_type == UserTransferType::TransferFromPermit2 {
+        let function_signature = if user_transfer_type == UserTransferType::TransferFromPermit2 {
             "sequentialSwapPermit2(uint256,address,address,uint256,bool,bool,address,((address,uint160,uint48,uint48),address,uint256),bytes,bytes)"
         } else {
             "sequentialSwap(uint256,address,address,uint256,bool,bool,address,bool,bytes)"
 
         }.to_string();
         Ok(Self {
-            selector,
+            function_signature,
             swap_encoder_registry,
             router_address: router_address.clone(),
             native_address: chain.native_token()?,
@@ -288,7 +288,7 @@ impl StrategyEncoder for SequentialSwapStrategyEncoder {
         let encoded_swaps = ple_encode(swaps);
         Ok(EncodedSolution {
             interacting_with: self.router_address.clone(),
-            selector: self.selector.clone(),
+            function_signature: self.function_signature.clone(),
             swaps: encoded_swaps,
             permit: None,
             n_tokens: 0,
@@ -309,7 +309,7 @@ impl StrategyEncoder for SequentialSwapStrategyEncoder {
 ///
 /// # Fields
 /// * `swap_encoder_registry`: SwapEncoderRegistry, containing all possible swap encoders
-/// * `selector`: String, the selector for the swap function in the router contract
+/// * `function_signature`: String, the signature for the swap function in the router contract
 /// * `native_address`: Address of the chain's native token
 /// * `wrapped_address`: Address of the chain's wrapped token
 /// * `split_swap_validator`: SplitSwapValidator, responsible for checking validity of split swap
@@ -319,7 +319,7 @@ impl StrategyEncoder for SequentialSwapStrategyEncoder {
 #[derive(Clone)]
 pub struct SplitSwapStrategyEncoder {
     swap_encoder_registry: SwapEncoderRegistry,
-    selector: String,
+    function_signature: String,
     native_address: Bytes,
     wrapped_address: Bytes,
     split_swap_validator: SplitSwapValidator,
@@ -334,13 +334,13 @@ impl SplitSwapStrategyEncoder {
         user_transfer_type: UserTransferType,
         router_address: Bytes,
     ) -> Result<Self, EncodingError> {
-        let selector = if user_transfer_type == UserTransferType::TransferFromPermit2 {
+        let function_signature = if user_transfer_type == UserTransferType::TransferFromPermit2 {
            "splitSwapPermit2(uint256,address,address,uint256,bool,bool,uint256,address,((address,uint160,uint48,uint48),address,uint256),bytes,bytes)"
         } else {
                 "splitSwap(uint256,address,address,uint256,bool,bool,uint256,address,bool,bytes)"
         }.to_string();
         Ok(Self {
-            selector,
+            function_signature,
             swap_encoder_registry,
             native_address: chain.native_token()?,
             wrapped_address: chain.wrapped_token()?,
@@ -489,7 +489,7 @@ impl StrategyEncoder for SplitSwapStrategyEncoder {
         };
         Ok(EncodedSolution {
             interacting_with: self.router_address.clone(),
-            selector: self.selector.clone(),
+            function_signature: self.function_signature.clone(),
             swaps: encoded_swaps,
             permit: None,
             n_tokens: tokens_len,
@@ -596,7 +596,7 @@ mod tests {
             let hex_calldata = encode(&encoded_solution.swaps);
 
             assert_eq!(hex_calldata, expected_swap);
-            assert_eq!(encoded_solution.selector, "singleSwapPermit2(uint256,address,address,uint256,bool,bool,address,((address,uint160,uint48,uint48),address,uint256),bytes,bytes)".to_string());
+            assert_eq!(encoded_solution.function_signature, "singleSwapPermit2(uint256,address,address,uint256,bool,bool,address,((address,uint160,uint48,uint48),address,uint256),bytes,bytes)".to_string());
             assert_eq!(encoded_solution.interacting_with, router_address());
         }
 
@@ -659,7 +659,7 @@ mod tests {
 
             assert_eq!(hex_calldata, expected_input);
             assert_eq!(
-                encoded_solution.selector,
+                encoded_solution.function_signature,
                 "singleSwap(uint256,address,address,uint256,bool,bool,address,bool,bytes)"
                     .to_string()
             );
@@ -747,7 +747,7 @@ mod tests {
 
             assert_eq!(hex_calldata, expected);
             assert_eq!(
-                encoded_solution.selector,
+                encoded_solution.function_signature,
                 "sequentialSwap(uint256,address,address,uint256,bool,bool,address,bool,bytes)"
                     .to_string()
             );
@@ -902,7 +902,7 @@ mod tests {
             .join("");
             assert_eq!(hex_calldata, expected_swaps);
             assert_eq!(
-                encoded_solution.selector,
+                encoded_solution.function_signature,
                 "splitSwapPermit2(uint256,address,address,uint256,bool,bool,uint256,address,((address,uint160,uint48,uint48),address,uint256),bytes,bytes)"
                     .to_string()
             );
@@ -1050,7 +1050,7 @@ mod tests {
 
             assert_eq!(hex_calldata, expected_swaps);
             assert_eq!(
-                encoded_solution.selector,
+                encoded_solution.function_signature,
                 "splitSwap(uint256,address,address,uint256,bool,bool,uint256,address,bool,bytes)"
                     .to_string()
             );

src/encoding/evm/swap_encoder/swap_encoders.rs

@@ -19,7 +19,6 @@ use crate::encoding::{
 ///
 /// # Fields
 /// * `executor_address` - The address of the executor contract that will perform the swap.
-/// * `swap_selector` - The selector of the swap function in the executor contract.
 #[derive(Clone)]
 pub struct UniswapV2SwapEncoder {
     executor_address: String,
@@ -78,7 +77,6 @@ impl SwapEncoder for UniswapV2SwapEncoder {
 ///
 /// # Fields
 /// * `executor_address` - The address of the executor contract that will perform the swap.
-/// * `swap_selector` - The selector of the swap function in the executor contract.
 #[derive(Clone)]
 pub struct UniswapV3SwapEncoder {
     executor_address: String,
@@ -140,8 +138,6 @@ impl SwapEncoder for UniswapV3SwapEncoder {
 ///
 /// # Fields
 /// * `executor_address` - The address of the executor contract that will perform the swap.
-/// * `swap_selector` - The selector of the swap function in the executor contract.
-/// * `callback_selector` - The selector of the callback function in the executor contract.
 #[derive(Clone)]
 pub struct UniswapV4SwapEncoder {
     executor_address: String,

src/encoding/evm/tycho_encoders.rs

@@ -337,7 +337,7 @@ impl TychoExecutorEncoder {
             swaps: grouped_protocol_data,
             interacting_with: executor_address,
             permit: None,
-            selector: "".to_string(),
+            function_signature: "".to_string(),
             n_tokens: 0,
         })
     }

src/encoding/evm/utils.rs

@@ -9,7 +9,7 @@ use alloy::{
     providers::{ProviderBuilder, RootProvider},
     transports::BoxTransport,
 };
-use alloy_primitives::{aliases::U24, Address, Keccak256, U256, U8};
+use alloy_primitives::{aliases::U24, Address, U256, U8};
 use alloy_sol_types::SolValue;
 use num_bigint::BigUint;
 use once_cell::sync::Lazy;
@@ -159,25 +159,3 @@ pub fn write_calldata_to_file(test_identifier: &str, hex_calldata: &str) {
         writeln!(file, "{line}").expect("Failed to write calldata");
     }
 }
-
-/// Encodes the input data for a function call to the given function selector.
-pub fn encode_input(selector: &str, mut encoded_args: Vec<u8>) -> Vec<u8> {
-    let mut hasher = Keccak256::new();
-    hasher.update(selector.as_bytes());
-    let selector_bytes = &hasher.finalize()[..4];
-    let mut call_data = selector_bytes.to_vec();
-    // Remove extra prefix if present (32 bytes for dynamic data)
-    // Alloy encoding is including a prefix for dynamic data indicating the offset or length
-    // but at this point we don't want that
-    if encoded_args.len() > 32 &&
-        encoded_args[..32] ==
-            [0u8; 31]
-                .into_iter()
-                .chain([32].to_vec())
-                .collect::<Vec<u8>>()
-    {
-        encoded_args = encoded_args[32..].to_vec();
-    }
-    call_data.extend(encoded_args);
-    call_data
-}

src/encoding/models.rs

@@ -105,7 +105,6 @@ impl Swap {
 /// * `to`: Address of the contract to call with the calldata
 /// * `value`: Native token value to be sent with the transaction.
 /// * `data`: Encoded calldata for the transaction.
-/// * `selector`: Only relevant for direct executions. The selector of the function to be called.
 #[derive(Clone, Debug)]
 pub struct Transaction {
     pub to: Bytes,
@@ -118,14 +117,14 @@ pub struct Transaction {
 /// # Fields
 /// * `swaps`: Encoded swaps to be executed.
 /// * `interacting_with`: Address of the contract to be called.
-/// * `selector`: The selector of the function to be called.
+/// * `function_signature`: The signature of the function to be called.
 /// * `n_tokens`: Number of tokens in the swap.
 /// * `permit`: Optional permit for the swap (if permit2 is enabled).
 #[derive(Clone, Debug)]
 pub struct EncodedSolution {
     pub swaps: Vec<u8>,
     pub interacting_with: Bytes,
-    pub selector: String,
+    pub function_signature: String,
     pub n_tokens: usize,
     pub permit: Option<PermitSingle>,
 }

src/encoding/tycho_encoder.rs

@@ -26,8 +26,8 @@ use crate::encoding::{
 /// outer function call arguments themselves** and verify that they enforce correct and secure
 /// behavior.
 pub trait TychoEncoder {
-    /// Encodes a list of [`Solution`]s into [`EncodedSolution`]s, which include the selector and
+    /// Encodes a list of [`Solution`]s into [`EncodedSolution`]s, which include the function
-    /// internal swap call data.
+    /// signature and internal swap call data.
     ///
     /// This method gives users maximum flexibility and control. It **does not** produce full
     /// transaction objects. Users are responsible for:
@@ -36,7 +36,7 @@ pub trait TychoEncoder {
     ///
     /// # Returns
     /// A vector of encoded solutions, each containing:
-    /// - The Tycho method selector
+    /// - The Tycho method function signature
     /// - The encoded swap path
     /// - Additional metadata (e.g., permit2 information)
     ///