Subsidize RBF

contracts/satoshi-bridge/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "satoshi-bridge"
-version = "0.7.0"
+version = "0.8.0"
 edition.workspace = true
 publish.workspace = true
 repository.workspace = true

contracts/satoshi-bridge/src/api/bridge.rs

@@ -449,6 +449,7 @@ impl Contract {
                 max_gas_fee: gas_fee,
                 last_rbf_time_sec: None,
                 cancel_rbf_reserved: None,
+                subsidize_amount: 0,
             }),
         };
         require!(

contracts/satoshi-bridge/src/api/token_receiver.rs

@@ -14,6 +14,10 @@ pub enum TokenReceiverMessage {
         output: Vec<TxOut>,
         max_gas_fee: Option<U128>,
     },
+    Rbf {
+        pending_tx_id: String,
+        output: Vec<TxOut>,
+    },
 }
 
 #[near]
@@ -26,10 +30,6 @@ impl FungibleTokenReceiver for Contract {
         msg: String,
     ) -> PromiseOrValue<U128> {
         let amount = amount.into();
-        require!(
-            amount >= self.internal_config().min_withdraw_amount,
-            "Invalid amount"
-        );
         let message = serde_json::from_str::<TokenReceiverMessage>(&msg).expect("INVALID MSG");
         let token_id = env::predecessor_account_id();
         require!(
@@ -52,14 +52,24 @@ impl FungibleTokenReceiver for Contract {
                 input,
                 output,
                 max_gas_fee,
-            } => self.ft_on_transfer_withdraw_chain_specific(
-                sender_id,
-                amount,
-                target_btc_address,
-                input,
+            } => {
+                require!(
+                    amount >= self.internal_config().min_withdraw_amount,
+                    "Invalid amount"
+                );
+                self.ft_on_transfer_withdraw_chain_specific(
+                    sender_id,
+                    amount,
+                    target_btc_address,
+                    input,
+                    output,
+                    max_gas_fee,
+                )
+            }
+            TokenReceiverMessage::Rbf {
+                pending_tx_id,
                 output,
-                max_gas_fee,
-            ),
+            } => self.rbf_subsidize_chain_specific(amount, sender_id, pending_tx_id, output),
         }
     }
 }
@@ -119,6 +129,7 @@ impl Contract {
                 max_gas_fee: gas_fee,
                 last_rbf_time_sec: None,
                 cancel_rbf_reserved: None,
+                subsidize_amount: 0,
             }),
         };
         require!(

contracts/satoshi-bridge/src/bitcoin_utils/contract_methods.rs

@@ -11,7 +11,7 @@ macro_rules! define_rbf_method {
             account_id: AccountId,
             original_btc_pending_verify_id: String,
             output: Vec<TxOut>,
-        ) {
+        ) -> String {
             let original_tx_btc_pending_info =
                 self.internal_unwrap_btc_pending_info(&original_btc_pending_verify_id);
 
@@ -31,6 +31,8 @@ macro_rules! define_rbf_method {
                 btc_pending_id: &btc_pending_id,
             }
             .emit();
+
+            btc_pending_id
         }
     };
 }
@@ -45,7 +47,10 @@ impl Contract {
         // Ensure that the RBF transaction pays more gas than the previous transaction.
         let max_gas_fee = original_tx_btc_pending_info.get_max_gas_fee();
         let additional_gas_amount = gas_fee.saturating_sub(max_gas_fee);
-        require!(additional_gas_amount > 0, "No gas increase.");
+        require!(
+            additional_gas_amount > 0,
+            format!("No gas increase. Old gas fee = {max_gas_fee}, new gas fee = {gas_fee}")
+        );
     }
 
     pub(crate) fn ft_on_transfer_withdraw_chain_specific(
@@ -97,4 +102,60 @@ impl Contract {
         let original_psbt = original_tx_btc_pending_info.get_psbt();
         PsbtWrapper::from_original_psbt(original_psbt, output)
     }
+
+    pub(crate) fn rbf_subsidize_chain_specific(
+        &mut self,
+        amount: u128,
+        sender_id: AccountId,
+        pending_tx_id: String,
+        output: Vec<TxOut>,
+    ) -> PromiseOrValue<U128> {
+        let origin_tx_btc_pending_info = self.internal_unwrap_btc_pending_info(&pending_tx_id);
+        let user_account_id = origin_tx_btc_pending_info.account_id.clone();
+        require!(
+            self.internal_unwrap_account(&user_account_id)
+                .btc_pending_sign_id
+                .is_none(),
+            "Assisted user previous btc tx has not been signed"
+        );
+        let full_subsidy_amount = self
+            .internal_unwrap_btc_pending_info(&pending_tx_id)
+            .get_subsidize_amount()
+            + amount;
+        self.internal_unwrap_mut_btc_pending_info(&pending_tx_id)
+            .update_subsidize_amount(full_subsidy_amount);
+
+        let new_pending_info_id = self.withdraw_rbf_chain_specific(
+            user_account_id.clone(),
+            pending_tx_id.clone(),
+            output,
+        );
+
+        let origin_tx_btc_pending_info = self.internal_unwrap_btc_pending_info(&pending_tx_id);
+        let new_tx_btc_pending_info = self.internal_unwrap_btc_pending_info(&new_pending_info_id);
+
+        require!(
+            new_tx_btc_pending_info.actual_received_amount
+                == origin_tx_btc_pending_info.actual_received_amount,
+            "Actual received amount has been changed."
+        );
+        let gas_fee_diff = new_tx_btc_pending_info
+            .gas_fee
+            .saturating_sub(origin_tx_btc_pending_info.gas_fee);
+        require!(
+            gas_fee_diff == full_subsidy_amount,
+            "Gas fee diff is not equal to subsidy amount."
+        );
+
+        Event::SubsidizeRbf {
+            origin_btc_pending_id: &pending_tx_id,
+            subsidy_amount: U128(amount),
+            full_subsidy_amount: U128(full_subsidy_amount),
+            subsidizer: &sender_id,
+            beneficiary: &user_account_id,
+        }
+        .emit();
+
+        PromiseOrValue::Value(U128(0))
+    }
 }

contracts/satoshi-bridge/src/bitcoin_utils/psbt_wrapper.rs

@@ -42,7 +42,7 @@ impl PsbtWrapper {
         original_psbt: crate::psbt_wrapper::PsbtWrapper,
         output: Vec<TxOut>,
     ) -> Self {
-        let sequence = bitcoin::Sequence::MAX;
+        let sequence = bitcoin::Sequence::ENABLE_RBF_NO_LOCKTIME;
 
         let transaction = BtcTransaction {
             version: Version::TWO,

contracts/satoshi-bridge/src/btc_pending_info.rs

@@ -12,6 +12,8 @@ pub struct OriginalState {
     pub max_gas_fee: u128,
     pub last_rbf_time_sec: Option<u32>,
     pub cancel_rbf_reserved: Option<U128>,
+    #[serde(with = "u128_dec_format")]
+    pub subsidize_amount: u128,
 }
 
 impl OriginalState {
@@ -199,6 +201,28 @@ impl BTCPendingInfo {
             _ => env::panic_str("Not original tx"),
         }
     }
+
+    pub fn get_subsidize_amount(&self) -> u128 {
+        match self.state.borrow() {
+            PendingInfoState::WithdrawOriginal(state) => state.subsidize_amount,
+            PendingInfoState::ActiveUtxoManagementOriginal(state) => state.subsidize_amount,
+            _ => env::panic_str("Not original tx"),
+        }
+    }
+
+    pub fn update_subsidize_amount(&mut self, subsidize_amount: u128) {
+        match self.state.borrow_mut() {
+            PendingInfoState::WithdrawOriginal(state) => {
+                state.subsidize_amount = subsidize_amount;
+                state.last_rbf_time_sec = Some(nano_to_sec(env::block_timestamp()));
+            }
+            PendingInfoState::ActiveUtxoManagementOriginal(state) => {
+                state.subsidize_amount = subsidize_amount;
+                state.last_rbf_time_sec = Some(nano_to_sec(env::block_timestamp()));
+            }
+            _ => env::panic_str("Not original tx"),
+        }
+    }
 
     pub fn to_pending_verify_stage(&mut self) {
         match self.state.borrow_mut() {
@@ -293,12 +317,14 @@ impl BTCPendingInfo {
 
 #[near(serializers = [borsh])]
 pub enum VBTCPendingInfo {
+    V0(BTCPendingInfoV0),
     Current(BTCPendingInfo),
 }
 
 impl From<VBTCPendingInfo> for BTCPendingInfo {
     fn from(v: VBTCPendingInfo) -> Self {
         match v {
+            VBTCPendingInfo::V0(c) => c.into(),
             VBTCPendingInfo::Current(c) => c,
         }
     }
@@ -307,6 +333,7 @@ impl From<VBTCPendingInfo> for BTCPendingInfo {
 impl From<&VBTCPendingInfo> for BTCPendingInfo {
     fn from(v: &VBTCPendingInfo) -> Self {
         match v {
+            VBTCPendingInfo::V0(c) => c.clone().into(),
             VBTCPendingInfo::Current(c) => c.clone(),
         }
     }
@@ -315,6 +342,7 @@ impl From<&VBTCPendingInfo> for BTCPendingInfo {
 impl<'a> From<&'a VBTCPendingInfo> for &'a BTCPendingInfo {
     fn from(v: &'a VBTCPendingInfo) -> Self {
         match v {
+            VBTCPendingInfo::V0(_) => unreachable!(),
             VBTCPendingInfo::Current(c) => c,
         }
     }
@@ -323,6 +351,7 @@ impl<'a> From<&'a VBTCPendingInfo> for &'a BTCPendingInfo {
 impl<'a> From<&'a mut VBTCPendingInfo> for &'a mut BTCPendingInfo {
     fn from(v: &'a mut VBTCPendingInfo) -> Self {
         match v {
+            VBTCPendingInfo::V0(_) => unreachable!(),
             VBTCPendingInfo::Current(c) => c,
         }
     }
@@ -361,11 +390,18 @@ impl Contract {
         &mut self,
         btc_pending_id: &String,
     ) -> &mut BTCPendingInfo {
-        self.data_mut()
+        let btc_pending_info = self
+            .data_mut()
             .btc_pending_infos
             .get_mut(btc_pending_id)
-            .map(|o| o.into())
-            .expect("BTC pending info not exist")
+            .expect("BTC pending info not exist");
+
+        if let VBTCPendingInfo::V0(old) = &btc_pending_info {
+            let new_current = BTCPendingInfo::from(old.clone());
+            *btc_pending_info = VBTCPendingInfo::Current(new_current);
+        }
+
+        btc_pending_info.into()
     }
 
     pub fn internal_remove_btc_pending_info(&mut self, btc_pending_id: &String) -> BTCPendingInfo {

contracts/satoshi-bridge/src/event.rs

@@ -44,6 +44,13 @@ pub enum Event<'a> {
         account_id: &'a AccountId,
         btc_pending_id: &'a String,
     },
+    SubsidizeRbf {
+        origin_btc_pending_id: &'a String,
+        subsidy_amount: U128,
+        full_subsidy_amount: U128,
+        subsidizer: &'a AccountId,
+        beneficiary: &'a AccountId,
+    },
     BtcInputSignature {
         account_id: &'a AccountId,
         btc_pending_id: &'a String,