protocol liquidation fee configurable

token-lending/program/src/instruction.rs

@@ -444,7 +444,8 @@ impl LendingInstruction {
                 let (host_fee_percentage, rest) = Self::unpack_u8(rest)?;
                 let (deposit_limit, rest) = Self::unpack_u64(rest)?;
                 let (borrow_limit, rest) = Self::unpack_u64(rest)?;
-                let (fee_receiver, _) = Self::unpack_pubkey(rest)?;
+                let (fee_receiver, rest) = Self::unpack_pubkey(rest)?;
+                let (protocol_liquidation_fee, _rest) = Self::unpack_u8(rest)?;
                 Self::InitReserve {
                     liquidity_amount,
                     config: ReserveConfig {
@@ -463,6 +464,7 @@ impl LendingInstruction {
                         deposit_limit,
                         borrow_limit,
                         fee_receiver,
+                        protocol_liquidation_fee,
                     },
                 }
             }
@@ -510,20 +512,20 @@ impl LendingInstruction {
                 Self::WithdrawObligationCollateralAndRedeemReserveCollateral { collateral_amount }
             }
             16 => {
-                let (optimal_utilization_rate, _rest) = Self::unpack_u8(rest)?;
-                let (loan_to_value_ratio, _rest) = Self::unpack_u8(_rest)?;
-                let (liquidation_bonus, _rest) = Self::unpack_u8(_rest)?;
-                let (liquidation_threshold, _rest) = Self::unpack_u8(_rest)?;
-                let (min_borrow_rate, _rest) = Self::unpack_u8(_rest)?;
-                let (optimal_borrow_rate, _rest) = Self::unpack_u8(_rest)?;
-                let (max_borrow_rate, _rest) = Self::unpack_u8(_rest)?;
-                let (borrow_fee_wad, _rest) = Self::unpack_u64(_rest)?;
-                let (flash_loan_fee_wad, _rest) = Self::unpack_u64(_rest)?;
-                let (host_fee_percentage, _rest) = Self::unpack_u8(_rest)?;
-                let (deposit_limit, _rest) = Self::unpack_u64(_rest)?;
-                let (borrow_limit, _rest) = Self::unpack_u64(_rest)?;
-                let (fee_receiver, _) = Self::unpack_pubkey(_rest)?;
-
+                let (optimal_utilization_rate, rest) = Self::unpack_u8(rest)?;
+                let (loan_to_value_ratio, rest) = Self::unpack_u8(rest)?;
+                let (liquidation_bonus, rest) = Self::unpack_u8(rest)?;
+                let (liquidation_threshold, rest) = Self::unpack_u8(rest)?;
+                let (min_borrow_rate, rest) = Self::unpack_u8(rest)?;
+                let (optimal_borrow_rate, rest) = Self::unpack_u8(rest)?;
+                let (max_borrow_rate, rest) = Self::unpack_u8(rest)?;
+                let (borrow_fee_wad, rest) = Self::unpack_u64(rest)?;
+                let (flash_loan_fee_wad, rest) = Self::unpack_u64(rest)?;
+                let (host_fee_percentage, rest) = Self::unpack_u8(rest)?;
+                let (deposit_limit, rest) = Self::unpack_u64(rest)?;
+                let (borrow_limit, rest) = Self::unpack_u64(rest)?;
+                let (fee_receiver, rest) = Self::unpack_pubkey(rest)?;
+                let (protocol_liquidation_fee, _rest) = Self::unpack_u8(rest)?;
                 Self::UpdateReserveConfig {
                     config: ReserveConfig {
                         optimal_utilization_rate,
@@ -541,6 +543,7 @@ impl LendingInstruction {
                         deposit_limit,
                         borrow_limit,
                         fee_receiver,
+                        protocol_liquidation_fee,
                     },
                 }
             }
@@ -643,6 +646,7 @@ impl LendingInstruction {
                         deposit_limit,
                         borrow_limit,
                         fee_receiver,
+                        protocol_liquidation_fee,
                     },
             } => {
                 buf.push(2);
@@ -660,6 +664,7 @@ impl LendingInstruction {
                 buf.extend_from_slice(&deposit_limit.to_le_bytes());
                 buf.extend_from_slice(&borrow_limit.to_le_bytes());
                 buf.extend_from_slice(&fee_receiver.to_bytes());
+                buf.extend_from_slice(&protocol_liquidation_fee.to_le_bytes());
             }
             Self::RefreshReserve => {
                 buf.push(3);
@@ -725,6 +730,7 @@ impl LendingInstruction {
                 buf.extend_from_slice(&config.deposit_limit.to_le_bytes());
                 buf.extend_from_slice(&config.borrow_limit.to_le_bytes());
                 buf.extend_from_slice(&config.fee_receiver.to_bytes());
+                buf.extend_from_slice(&config.protocol_liquidation_fee.to_le_bytes());
             }
             Self::LiquidateObligationAndRedeemReserveCollateral { liquidity_amount } => {
                 buf.push(17);

token-lending/program/src/processor.rs

@@ -2556,6 +2556,10 @@ fn validate_reserve_config(config: ReserveConfig) -> ProgramResult {
         msg!("Host fee percentage must be in range [0, 100]");
         return Err(LendingError::InvalidConfig.into());
     }
+    if config.protocol_liquidation_fee >= 100 {
+        msg!("Protocol liquidation fee must be in range [0, 100)");
+        return Err(LendingError::InvalidConfig.into());
+    }
     Ok(())
 }
 

token-lending/program/src/state/reserve.rs

@@ -307,6 +307,8 @@ impl Reserve {
 
         let bonus = amount_liquidated_wads.try_sub(amount_liquidated_wads.try_div(bonus_rate)?)?;
 
+        // After deploying must update all reserves to set liquidation fee then redeploy with this line instead of hardcode
+        // let protocol_fee = bonus.try_mul(Rate::from_percent(self.config.protocol_liquidation_fee))?.try_ceil_u64()?;
         let protocol_fee = bonus.try_mul(Rate::from_percent(30))?.try_ceil_u64()?;
         Ok(protocol_fee)
     }
@@ -629,6 +631,8 @@ pub struct ReserveConfig {
     pub borrow_limit: u64,
     /// Reserve liquidity fee receiver address
     pub fee_receiver: Pubkey,
+    /// Cut of the liquidation bonus that the protocol receives, as a percentage
+    pub protocol_liquidation_fee: u8,
 }
 
 /// Additional fee information on a reserve
@@ -739,7 +743,7 @@ impl IsInitialized for Reserve {
     }
 }
 
-const RESERVE_LEN: usize = 619; // 1 + 8 + 1 + 32 + 32 + 1 + 32 + 32 + 32 + 8 + 16 + 16 + 16 + 32 + 8 + 32 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 8 + 8 + 1 + 8 + 8 + 32 + 248
+const RESERVE_LEN: usize = 619; // 1 + 8 + 1 + 32 + 32 + 1 + 32 + 32 + 32 + 8 + 16 + 16 + 16 + 32 + 8 + 32 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 8 + 8 + 1 + 8 + 8 + 32 + 1 + 247
 impl Pack for Reserve {
     const LEN: usize = RESERVE_LEN;
 
@@ -777,6 +781,7 @@ impl Pack for Reserve {
             config_deposit_limit,
             config_borrow_limit,
             config_fee_receiver,
+            config_protocol_liquidation_fee,
             _padding,
         ) = mut_array_refs![
             output,
@@ -809,7 +814,8 @@ impl Pack for Reserve {
             8,
             8,
             PUBKEY_BYTES,
-            248
+            1,
+            247
         ];
 
         // reserve
@@ -855,6 +861,7 @@ impl Pack for Reserve {
         *config_deposit_limit = self.config.deposit_limit.to_le_bytes();
         *config_borrow_limit = self.config.borrow_limit.to_le_bytes();
         config_fee_receiver.copy_from_slice(self.config.fee_receiver.as_ref());
+        *config_protocol_liquidation_fee = self.config.protocol_liquidation_fee.to_le_bytes();
     }
 
     /// Unpacks a byte buffer into a [ReserveInfo](struct.ReserveInfo.html).
@@ -891,6 +898,7 @@ impl Pack for Reserve {
             config_deposit_limit,
             config_borrow_limit,
             config_fee_receiver,
+            config_protocol_liquidation_fee,
             _padding,
         ) = array_refs![
             input,
@@ -923,7 +931,8 @@ impl Pack for Reserve {
             8,
             8,
             PUBKEY_BYTES,
-            248
+            1,
+            247
         ];
 
         let version = u8::from_le_bytes(*version);
@@ -973,6 +982,7 @@ impl Pack for Reserve {
                 deposit_limit: u64::from_le_bytes(*config_deposit_limit),
                 borrow_limit: u64::from_le_bytes(*config_borrow_limit),
                 fee_receiver: Pubkey::new_from_array(*config_fee_receiver),
+                protocol_liquidation_fee: u8::from_le_bytes(*config_protocol_liquidation_fee),
             },
         })
     }

token-lending/program/tests/helpers/mod.rs

@@ -56,6 +56,7 @@ pub fn test_reserve_config() -> ReserveConfig {
         deposit_limit: 100_000_000_000,
         borrow_limit: u64::MAX,
         fee_receiver: Keypair::new().pubkey(),
+        protocol_liquidation_fee: 30,
     }
 }
 

token-lending/program/tests/init_reserve.rs

@@ -418,6 +418,7 @@ async fn test_update_reserve_config() {
         deposit_limit: 1_000_000,
         borrow_limit: 300_000,
         fee_receiver: Keypair::new().pubkey(),
+        protocol_liquidation_fee: 30,
     };
 
     let (mut banks_client, payer, recent_blockhash) = test.start().await;

token-lending/program/tests/liquidate_obligation_and_redeem_collateral.rs

@@ -174,7 +174,7 @@ async fn test_success() {
     );
 
     assert_eq!(
-        // 30% of the bonus 
+        // 30% of the bonus
         SOL_LIQUIDATION_AMOUNT_LAMPORTS * 3 / 10 / 11,
         (fee_reciever_withdraw_liquidity_balance - initial_fee_reciever_withdraw_liquidity_balance)
     );