solana: add base fee token

Author: a5-pickle

solana/programs/matching-engine/src/error.rs

@@ -81,6 +81,8 @@ pub enum MatchingEngineError {
     FastFillNotRedeemed = 0x435,
     ReservedSequenceMismatch = 0x438,
     AuctionAlreadySettled = 0x43a,
+    InvalidBaseFeeToken = 0x43c,
+    BaseFeeTokenRequired = 0x43e,
 
     CannotCloseAuctionYet = 0x500,
     AuctionHistoryNotFull = 0x502,

solana/programs/matching-engine/src/events/auction_settled.rs

@@ -18,8 +18,9 @@ pub struct AuctionSettled {
     pub best_offer_token: Option<SettledTokenAccountInfo>,
 
     /// Depending on whether there was an active auction, this field will have the pubkey of the
-    /// executor token (if there was an auction) or fee recipient token (if there was no auction).
-    pub executor_token: Option<SettledTokenAccountInfo>,
+    /// base fee token account (if there was an auction) or fee recipient token (if there was no
+    /// auction).
+    pub base_fee_token: Option<SettledTokenAccountInfo>,
 
     /// This value will only be some if there was no active auction.
     pub with_execute: Option<MessageProtocol>,

solana/programs/matching-engine/src/processor/auction/prepare_order_response/cctp.rs

@@ -97,6 +97,23 @@ pub struct PrepareOrderResponseCctp<'info> {
     )]
     prepared_custody_token: Box<Account<'info, token::TokenAccount>>,
 
+    /// This token account will be the one that collects the base fee only if an auction's order
+    /// was executed late. Otherwise, the protocol's fee recipient token account will be used for
+    /// non-existent auctions and the best offer token account will be used for orders executed on
+    /// time.
+    #[account(
+        token::mint = usdc,
+        constraint = {
+            require!(
+                base_fee_token.key() != prepared_custody_token.key(),
+                MatchingEngineError::InvalidBaseFeeToken
+            );
+
+            true
+        }
+    )]
+    base_fee_token: Box<Account<'info, token::TokenAccount>>,
+
     usdc: Usdc<'info>,
 
     cctp: CctpReceiveMessage<'info>,
@@ -216,6 +233,7 @@ fn handle_prepare_order_response_cctp(
             },
             info: PreparedOrderResponseInfo {
                 prepared_by: ctx.accounts.payer.key(),
+                base_fee_token: ctx.accounts.base_fee_token.key(),
                 source_chain: finalized_vaa.emitter_chain(),
                 base_fee: order_response.base_fee(),
                 fast_vaa_timestamp: fast_vaa.timestamp(),

solana/programs/matching-engine/src/processor/auction/settle/complete.rs

@@ -5,10 +5,7 @@ use crate::{
     utils,
 };
 use anchor_lang::prelude::*;
-use anchor_spl::{
-    associated_token::get_associated_token_address,
-    token::{self, TokenAccount},
-};
+use anchor_spl::token::{self, TokenAccount};
 
 #[derive(Accounts)]
 pub struct SettleAuctionComplete<'info> {
@@ -18,20 +15,24 @@ pub struct SettleAuctionComplete<'info> {
         mut,
         address = prepared_order_response.prepared_by,
     )]
-    executor: UncheckedAccount<'info>,
+    beneficiary: UncheckedAccount<'info>,
 
+    /// This token account will receive the base fee only if there was a penalty when executing the
+    /// order. If it does not exist when there is a penalty, this instruction handler will revert.
+    ///
+    /// CHECK: This account must be the same as the base fee token in the prepared order response.
     #[account(
         mut,
-        token::mint = common::USDC_MINT,
+        address = prepared_order_response.base_fee_token,
     )]
-    executor_token: Box<Account<'info, TokenAccount>>,
+    base_fee_token: UncheckedAccount<'info>,
 
     /// Destination token account, which the redeemer may not own. But because the redeemer is a
     /// signer and is the one encoded in the Deposit Fill message, he may have the tokens be sent
     /// to any account he chooses (this one).
     ///
     /// CHECK: This token account may exist. If it doesn't and there is a penalty, we will send all
-    /// of the tokens to the executor token account.
+    /// of the tokens to the base fee token account.
     #[account(
         mut,
         address = auction.info.as_ref().unwrap().best_offer_token,
@@ -40,7 +41,7 @@ pub struct SettleAuctionComplete<'info> {
 
     #[account(
         mut,
-        close = executor,
+        close = beneficiary,
         seeds = [
             PreparedOrderResponse::SEED_PREFIX,
             prepared_order_response.seeds.fast_vaa_hash.as_ref()
@@ -101,8 +102,8 @@ fn handle_settle_auction_complete(
         &[prepared_order_response.seeds.bump],
     ];
 
-    let executor = &ctx.accounts.executor;
-    let executor_token = &ctx.accounts.executor_token;
+    let beneficiary = &ctx.accounts.beneficiary;
+    let base_fee_token = &ctx.accounts.base_fee_token;
     let best_offer_token = &ctx.accounts.best_offer_token;
     let token_program = &ctx.accounts.token_program;
     let prepared_custody_token = &ctx.accounts.prepared_custody_token;
@@ -131,11 +132,15 @@ fn handle_settle_auction_complete(
             )
         }
         _ => {
+            let base_fee_token_data =
+                utils::checked_deserialize_token_account(base_fee_token, &common::USDC_MINT)
+                    .ok_or_else(|| MatchingEngineError::BaseFeeTokenRequired)?;
+
             // If the token account happens to not exist anymore, we will give everything to the
-            // executor.
+            // base fee token account.
             match utils::checked_deserialize_token_account(best_offer_token, &common::USDC_MINT) {
                 Some(best_offer) => {
-                    if executor_token.key() == best_offer_token.key() {
+                    if base_fee_token.key() == best_offer_token.key() {
                         (
                             None, // executor_result
                             TokenAccountResult {
@@ -145,31 +150,9 @@ fn handle_settle_auction_complete(
                             .into(),
                         )
                     } else {
-                        // Because the auction participant was penalized for executing the order
-                        // late, he will be deducted the base fee. This base fee will be sent to the
-                        // executor token account if it is not the same as the best offer token
-                        // account.
-
-                        // We require that the executor token account be an ATA.
-                        require_keys_eq!(
-                            executor_token.key(),
-                            get_associated_token_address(
-                                &executor_token.owner,
-                                &executor_token.mint
-                            ),
-                            ErrorCode::AccountNotAssociatedTokenAccount
-                        );
-
-                        // And enforce that the owner of this ATA is the executor.
-                        require_keys_eq!(
-                            executor.key(),
-                            executor_token.owner,
-                            ErrorCode::ConstraintTokenOwner,
-                        );
-
                         (
                             TokenAccountResult {
-                                balance_before: executor_token.amount,
+                                balance_before: base_fee_token_data.amount,
                                 amount: base_fee,
                             }
                             .into(),
@@ -183,7 +166,7 @@ fn handle_settle_auction_complete(
                 }
                 None => (
                     TokenAccountResult {
-                        balance_before: executor_token.amount,
+                        balance_before: base_fee_token_data.amount,
                         amount: repayment,
                     }
                     .into(),
@@ -193,7 +176,7 @@ fn handle_settle_auction_complete(
         }
     };
 
-    // Transfer executor his bounty if there are any.
+    // Transfer base fee token his bounty if there are any.
     let settled_executor_result = match executor_result {
         Some(TokenAccountResult {
             balance_before,
@@ -204,7 +187,7 @@ fn handle_settle_auction_complete(
                     token_program.to_account_info(),
                     token::Transfer {
                         from: prepared_custody_token.to_account_info(),
-                        to: executor_token.to_account_info(),
+                        to: base_fee_token.to_account_info(),
                         authority: prepared_order_response.to_account_info(),
                     },
                     &[prepared_order_response_signer_seeds],
@@ -213,7 +196,7 @@ fn handle_settle_auction_complete(
             )?;
 
             SettledTokenAccountInfo {
-                key: executor_token.key(),
+                key: base_fee_token.key(),
                 balance_after: balance_before.saturating_add(amount),
             }
             .into()
@@ -252,7 +235,7 @@ fn handle_settle_auction_complete(
     emit!(crate::events::AuctionSettled {
         auction: ctx.accounts.auction.key(),
         best_offer_token: settled_best_offer_result,
-        executor_token: settled_executor_result,
+        base_fee_token: settled_executor_result,
         with_execute: Default::default(),
     });
 
@@ -261,7 +244,7 @@ fn handle_settle_auction_complete(
         token_program.to_account_info(),
         token::CloseAccount {
             account: prepared_custody_token.to_account_info(),
-            destination: executor.to_account_info(),
+            destination: beneficiary.to_account_info(),
             authority: prepared_order_response.to_account_info(),
         },
         &[prepared_order_response_signer_seeds],

solana/programs/matching-engine/src/processor/auction/settle/none/mod.rs

@@ -84,7 +84,7 @@ fn settle_none_and_prepare_fill(accounts: SettleNoneAndPrepareFill<'_, '_>) -> R
     emit!(crate::events::AuctionSettled {
         auction: auction.key(),
         best_offer_token: Default::default(),
-        executor_token: crate::events::SettledTokenAccountInfo {
+        base_fee_token: crate::events::SettledTokenAccountInfo {
             key: fee_recipient_token.key(),
             balance_after: fee_recipient_token.amount.saturating_add(fee)
         }

solana/programs/matching-engine/src/state/prepared_order_response.rs

@@ -11,6 +11,7 @@ pub struct PreparedOrderResponseSeeds {
 #[derive(Debug, AnchorSerialize, AnchorDeserialize, Clone, InitSpace)]
 pub struct PreparedOrderResponseInfo {
     pub prepared_by: Pubkey,
+    pub base_fee_token: Pubkey,
 
     pub fast_vaa_timestamp: u32,
     pub source_chain: u16,

solana/programs/matching-engine/src/utils/mod.rs

@@ -45,7 +45,7 @@ pub fn require_local_endpoint(endpoint: &RouterEndpoint) -> Result<bool> {
 pub fn checked_deserialize_token_account(
     acc_info: &AccountInfo,
     expected_mint: &Pubkey,
-) -> Option<token::TokenAccount> {
+) -> Option<Box<token::TokenAccount>> {
     if acc_info.owner != &token::ID {
         None
     } else {
@@ -54,5 +54,6 @@ pub fn checked_deserialize_token_account(
         token::TokenAccount::try_deserialize(&mut &data[..])
             .ok()
             .filter(|token_data| &token_data.mint == expected_mint && !token_data.is_frozen())
+            .map(Box::new)
     }
 }

solana/ts/src/idl/json/matching_engine.json

@@ -1369,6 +1369,15 @@
           "name": "prepared_custody_token",
           "writable": true
         },
+        {
+          "name": "base_fee_token",
+          "docs": [
+            "This token account will be the one that collects the base fee only if an auction's order",
+            "was executed late. Otherwise, the protocol's fee recipient token account will be used for",
+            "non-existent auctions and the best offer token account will be used for orders executed on",
+            "time."
+          ]
+        },
         {
           "name": "usdc",
           "accounts": [
@@ -1834,14 +1843,19 @@
       ],
       "accounts": [
         {
-          "name": "executor",
+          "name": "beneficiary",
           "docs": [
             "finalized VAA."
           ],
           "writable": true
         },
         {
-          "name": "executor_token",
+          "name": "base_fee_token",
+          "docs": [
+            "This token account will receive the base fee only if there was a penalty when executing the",
+            "order. If it does not exist when there is a penalty, this instruction handler will revert.",
+            ""
+          ],
           "writable": true
         },
         {
@@ -1851,7 +1865,7 @@
             "signer and is the one encoded in the Deposit Fill message, he may have the tokens be sent",
             "to any account he chooses (this one).",
             "",
-            "of the tokens to the executor token account."
+            "of the tokens to the base fee token account."
           ],
           "writable": true
         },
@@ -3032,6 +3046,14 @@
       "code": 7082,
       "name": "AuctionAlreadySettled"
     },
+    {
+      "code": 7084,
+      "name": "InvalidBaseFeeToken"
+    },
+    {
+      "code": 7086,
+      "name": "BaseFeeTokenRequired"
+    },
     {
       "code": 7280,
       "name": "CannotCloseAuctionYet"
@@ -3474,10 +3496,11 @@
             }
           },
           {
-            "name": "executor_token",
+            "name": "base_fee_token",
             "docs": [
               "Depending on whether there was an active auction, this field will have the pubkey of the",
-              "executor token (if there was an auction) or fee recipient token (if there was no auction)."
+              "base fee token account (if there was an auction) or fee recipient token (if there was no",
+              "auction)."
             ],
             "type": {
               "option": {
@@ -4103,6 +4126,10 @@
             "name": "prepared_by",
             "type": "pubkey"
           },
+          {
+            "name": "base_fee_token",
+            "type": "pubkey"
+          },
           {
             "name": "fast_vaa_timestamp",
             "type": "u32"