add gas fee payer by adding a new payload type

api/src/transactions.rs

@@ -852,7 +852,10 @@ impl TransactionsApi {
                         })?;
                 // Verify the signed transaction
                 match signed_transaction.payload() {
-                    TransactionPayload::EntryFunction(entry_function) => {
+                    TransactionPayload::MultiAgentWithFeePayer(
+                        MultisigTransactionPayload::EntryFunction(entry_function),
+                    )
+                    | TransactionPayload::EntryFunction(entry_function) => {
                         TransactionsApi::validate_entry_function_payload_format(
                             ledger_info,
                             entry_function,
@@ -1270,7 +1273,6 @@ impl TransactionsApi {
             .map_err(|err| {
                 BasicError::bad_request_with_code(err, AptosErrorCode::InvalidInput, &ledger_info)
             })?;
-
         let raw_message = match request.secondary_signers {
             Some(secondary_signer_addresses) => signing_message(
                 &RawTransactionWithData::new_multi_agent(

api/types/src/convert.rs

@@ -189,7 +189,10 @@ impl<'a, R: MoveResolverExt + ?Sized> MoveConverter<'a, R> {
         use aptos_types::transaction::TransactionPayload::*;
         let ret = match payload {
             Script(s) => TransactionPayload::ScriptPayload(s.try_into()?),
-            EntryFunction(fun) => {
+            MultiAgentWithFeePayer(
+                aptos_types::transaction::MultisigTransactionPayload::EntryFunction(fun),
+            )
+            | EntryFunction(fun) => {
                 let (module, function, ty_args, args) = fun.into_inner();
                 let func_args = self
                     .inner
@@ -581,7 +584,10 @@ impl<'a, R: MoveResolverExt + ?Sized> MoveConverter<'a, R> {
         use aptos_types::transaction::TransactionPayload as Target;
 
         let ret = match payload {
-            TransactionPayload::EntryFunctionPayload(entry_func_payload) => {
+            TransactionPayload::EntryFunctionPayload(entry_func_payload)
+            | TransactionPayload::FeePayerPayload(
+                MultisigTransactionPayload::EntryFunctionPayload(entry_func_payload),
+            ) => {
                 let EntryFunctionPayload {
                     function,
                     type_arguments,
@@ -695,7 +701,6 @@ impl<'a, R: MoveResolverExt + ?Sized> MoveConverter<'a, R> {
                     transaction_payload,
                 })
             },
-
             // Deprecated. Will be removed in the future.
             TransactionPayload::ModuleBundlePayload(payload) => {
                 Target::ModuleBundle(ModuleBundle::new(

api/types/src/lib.rs

@@ -47,14 +47,14 @@ pub use table::{RawTableItemRequest, TableItemRequest};
 pub use transaction::{
     AccountSignature, BlockMetadataTransaction, DeleteModule, DeleteResource, DeleteTableItem,
     DirectWriteSet, Ed25519Signature, EncodeSubmissionRequest, EntryFunctionPayload, Event,
-    GasEstimation, GasEstimationBcs, GenesisPayload, GenesisTransaction, ModuleBundlePayload,
-    MultiAgentSignature, MultiEd25519Signature, MultisigPayload, MultisigTransactionPayload,
-    PendingTransaction, ScriptPayload, ScriptWriteSet, SubmitTransactionRequest, Transaction,
-    TransactionData, TransactionId, TransactionInfo, TransactionOnChainData, TransactionPayload,
-    TransactionSignature, TransactionSigningMessage, TransactionsBatchSingleSubmissionFailure,
-    TransactionsBatchSubmissionResult, UserCreateSigningMessageRequest, UserTransaction,
-    UserTransactionRequest, VersionedEvent, WriteModule, WriteResource, WriteSet, WriteSetChange,
-    WriteSetPayload, WriteTableItem,
+    FeePayerSignature, GasEstimation, GasEstimationBcs, GenesisPayload, GenesisTransaction,
+    ModuleBundlePayload, MultiAgentSignature, MultiEd25519Signature, MultisigPayload,
+    MultisigTransactionPayload, PendingTransaction, ScriptPayload, ScriptWriteSet,
+    SubmitTransactionRequest, Transaction, TransactionData, TransactionId, TransactionInfo,
+    TransactionOnChainData, TransactionPayload, TransactionSignature, TransactionSigningMessage,
+    TransactionsBatchSingleSubmissionFailure, TransactionsBatchSubmissionResult,
+    UserCreateSigningMessageRequest, UserTransaction, UserTransactionRequest, VersionedEvent,
+    WriteModule, WriteResource, WriteSet, WriteSetChange, WriteSetPayload, WriteTableItem,
 };
 pub use view::ViewRequest;
 pub use wrappers::{EventGuid, IdentifierWrapper, StateKeyWrapper};

api/types/src/transaction.rs

@@ -586,6 +586,7 @@ pub enum TransactionPayload {
     // Deprecated. Will be removed in the future.
     ModuleBundlePayload(ModuleBundlePayload),
     MultisigPayload(MultisigPayload),
+    FeePayerPayload(MultisigTransactionPayload),
 }
 
 impl VerifyInput for TransactionPayload {
@@ -594,6 +595,9 @@ impl VerifyInput for TransactionPayload {
             TransactionPayload::EntryFunctionPayload(inner) => inner.verify(),
             TransactionPayload::ScriptPayload(inner) => inner.verify(),
             TransactionPayload::MultisigPayload(inner) => inner.verify(),
+            TransactionPayload::FeePayerPayload(
+                MultisigTransactionPayload::EntryFunctionPayload(inner),
+            ) => inner.function.verify(),
             // Deprecated. Will be removed in the future.
             TransactionPayload::ModuleBundlePayload(inner) => inner.verify(),
         }
@@ -848,6 +852,7 @@ pub enum TransactionSignature {
     Ed25519Signature(Ed25519Signature),
     MultiEd25519Signature(MultiEd25519Signature),
     MultiAgentSignature(MultiAgentSignature),
+    FeePayerSignature(FeePayerSignature),
 }
 
 impl VerifyInput for TransactionSignature {
@@ -856,6 +861,7 @@ impl VerifyInput for TransactionSignature {
             TransactionSignature::Ed25519Signature(inner) => inner.verify(),
             TransactionSignature::MultiEd25519Signature(inner) => inner.verify(),
             TransactionSignature::MultiAgentSignature(inner) => inner.verify(),
+            TransactionSignature::FeePayerSignature(inner) => inner.verify(),
         }
     }
 }
@@ -868,6 +874,7 @@ impl TryFrom<TransactionSignature> for TransactionAuthenticator {
             TransactionSignature::Ed25519Signature(sig) => sig.try_into()?,
             TransactionSignature::MultiEd25519Signature(sig) => sig.try_into()?,
             TransactionSignature::MultiAgentSignature(sig) => sig.try_into()?,
+            TransactionSignature::FeePayerSignature(sig) => sig.try_into()?,
         })
     }
 }
@@ -1228,6 +1235,89 @@ impl
     }
 }
 
+/// Fee payer signature for fee payer transactions
+///
+/// This allows you to have transactions across multiple accounts and with a fee payer
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Object)]
+pub struct FeePayerSignature {
+    pub sender: AccountSignature,
+    /// The other involved parties' addresses
+    pub secondary_signer_addresses: Vec<Address>,
+    /// The associated signatures, in the same order as the secondary addresses
+    pub secondary_signers: Vec<AccountSignature>,
+    /// The address of the paying party
+    pub fee_payer_address: Address,
+    /// The signature of the fee payer
+    pub fee_payer_signer: AccountSignature,
+}
+
+impl VerifyInput for FeePayerSignature {
+    fn verify(&self) -> anyhow::Result<()> {
+        self.sender.verify()?;
+
+        for signer in self.secondary_signers.iter() {
+            signer.verify()?;
+        }
+        self.fee_payer_signer.verify()?;
+        Ok(())
+    }
+}
+
+impl TryFrom<FeePayerSignature> for TransactionAuthenticator {
+    type Error = anyhow::Error;
+
+    fn try_from(value: FeePayerSignature) -> Result<Self, Self::Error> {
+        let FeePayerSignature {
+            sender,
+            secondary_signer_addresses,
+            secondary_signers,
+            fee_payer_address,
+            fee_payer_signer,
+        } = value;
+        Ok(TransactionAuthenticator::fee_payer(
+            sender.try_into()?,
+            secondary_signer_addresses
+                .into_iter()
+                .map(|a| a.into())
+                .collect(),
+            secondary_signers
+                .into_iter()
+                .map(|s| s.try_into())
+                .collect::<anyhow::Result<_>>()?,
+            fee_payer_address.into(),
+            fee_payer_signer.try_into()?,
+        ))
+    }
+}
+
+impl
+    From<(
+        &AccountAuthenticator,
+        &Vec<AccountAddress>,
+        &Vec<AccountAuthenticator>,
+        &AccountAddress,
+        &AccountAuthenticator,
+    )> for FeePayerSignature
+{
+    fn from(
+        (sender, addresses, signers, fee_payer_address, fee_payer_signer): (
+            &AccountAuthenticator,
+            &Vec<AccountAddress>,
+            &Vec<AccountAuthenticator>,
+            &AccountAddress,
+            &AccountAuthenticator,
+        ),
+    ) -> Self {
+        Self {
+            sender: sender.into(),
+            secondary_signer_addresses: addresses.iter().map(|address| (*address).into()).collect(),
+            secondary_signers: signers.iter().map(|s| s.into()).collect(),
+            fee_payer_address: (*fee_payer_address).into(),
+            fee_payer_signer: fee_payer_signer.into(),
+        }
+    }
+}
+
 impl From<TransactionAuthenticator> for TransactionSignature {
     fn from(auth: TransactionAuthenticator) -> Self {
         use TransactionAuthenticator::*;
@@ -1247,6 +1337,22 @@ impl From<TransactionAuthenticator> for TransactionSignature {
             } => Self::MultiAgentSignature(
                 (sender, secondary_signer_addresses, secondary_signers).into(),
             ),
+            FeePayer {
+                sender,
+                secondary_signer_addresses,
+                secondary_signers,
+                fee_payer_address,
+                fee_payer_signer,
+            } => Self::FeePayerSignature(
+                (
+                    sender,
+                    secondary_signer_addresses,
+                    secondary_signers,
+                    fee_payer_address,
+                    fee_payer_signer,
+                )
+                    .into(),
+            ),
         }
     }
 }

aptos-move/aptos-debugger/src/lib.rs

@@ -15,8 +15,8 @@ use aptos_types::{
     chain_id::ChainId,
     on_chain_config::{Features, OnChainConfig, TimedFeatures},
     transaction::{
-        SignedTransaction, Transaction, TransactionInfo, TransactionOutput, TransactionPayload,
-        Version,
+        MultisigTransactionPayload, SignedTransaction, Transaction, TransactionInfo,
+        TransactionOutput, TransactionPayload, Version,
     },
     vm_status::VMStatus,
 };
@@ -87,12 +87,17 @@ impl AptosDebugger {
                     );
                     let gas_profiler = match txn.payload() {
                         TransactionPayload::Script(_) => GasProfiler::new_script(gas_meter),
-                        TransactionPayload::EntryFunction(entry_func) => GasProfiler::new_function(
-                            gas_meter,
-                            entry_func.module().clone(),
-                            entry_func.function().to_owned(),
-                            entry_func.ty_args().to_vec(),
-                        ),
+                        TransactionPayload::MultiAgentWithFeePayer(
+                            MultisigTransactionPayload::EntryFunction(entry_func),
+                        )
+                        | TransactionPayload::EntryFunction(entry_func) => {
+                            GasProfiler::new_function(
+                                gas_meter,
+                                entry_func.module().clone(),
+                                entry_func.function().to_owned(),
+                                entry_func.ty_args().to_vec(),
+                            )
+                        },
                         TransactionPayload::ModuleBundle(..) => unreachable!("not supported"),
                         TransactionPayload::Multisig(..) => unimplemented!("not supported yet"),
                     };

aptos-move/aptos-vm/src/aptos_vm.rs

@@ -6,7 +6,7 @@ use crate::{
     adapter_common::{
         discard_error_output, discard_error_vm_status, PreprocessedTransaction, VMAdapter,
     },
-    aptos_vm_impl::{get_transaction_output, AptosVMImpl, AptosVMInternals, GAS_PAYER_FLAG_BIT},
+    aptos_vm_impl::{get_transaction_output, AptosVMImpl, AptosVMInternals},
     block_executor::BlockAptosVM,
     counters::*,
     data_cache::StorageAdapter,
@@ -394,18 +394,6 @@ impl AptosVM {
         )?)
     }
 
-    fn get_senders(txn_data: &TransactionMetadata) -> Vec<AccountAddress> {
-        let mut res = vec![txn_data.sender];
-        res.extend(txn_data.secondary_signers());
-        if txn_data.sequence_number & GAS_PAYER_FLAG_BIT != 0 {
-            // In a gas payer tx, the last multi-agent signer of the secondary signers is in
-            // fact the gas payer and not to be part of the tx parameters. So we remove the last
-            // signer.
-            res.pop();
-        }
-        res
-    }
-
     fn execute_script_or_entry_function(
         &self,
         resolver: &impl MoveResolverExt,
@@ -431,13 +419,12 @@ impl AptosVM {
 
             match payload {
                 TransactionPayload::Script(script) => {
-                    let senders = Self::get_senders(txn_data);
                     let loaded_func =
                         session.load_script(script.code(), script.ty_args().to_vec())?;
                     let args =
                         verifier::transaction_arg_validation::validate_combine_signer_and_txn_args(
                             &mut session,
-                            senders,
+                            txn_data.senders(),
                             convert_txn_args(script.args()),
                             &loaded_func,
                             self.0
@@ -452,11 +439,10 @@ impl AptosVM {
                     )?;
                 },
                 TransactionPayload::EntryFunction(script_fn) => {
-                    let senders = Self::get_senders(txn_data);
                     self.validate_and_execute_entry_function(
                         &mut session,
                         gas_meter,
-                        senders,
+                        txn_data.senders(),
                         script_fn,
                     )?;
                 },
@@ -1067,7 +1053,8 @@ impl AptosVM {
         let mut new_published_modules_loaded = false;
         let result = match txn.payload() {
             payload @ TransactionPayload::Script(_)
-            | payload @ TransactionPayload::EntryFunction(_) => self
+            | payload @ TransactionPayload::EntryFunction(_)
+            | payload @ TransactionPayload::MultiAgentWithFeePayer(_) => self
                 .execute_script_or_entry_function(
                     resolver,
                     session,
@@ -1460,7 +1447,8 @@ impl AptosVM {
                 self.0.check_gas(resolver, txn_data, log_context)?;
                 self.0.run_script_prologue(session, txn_data, log_context)
             },
-            TransactionPayload::EntryFunction(_) => {
+            TransactionPayload::EntryFunction(_)
+            | TransactionPayload::MultiAgentWithFeePayer(_) => {
                 // NOTE: Script and EntryFunction shares the same prologue
                 self.0.check_gas(resolver, txn_data, log_context)?;
                 self.0.run_script_prologue(session, txn_data, log_context)
@@ -1855,7 +1843,8 @@ impl AptosSimulationVM {
         let mut new_published_modules_loaded = false;
         let result = match txn.payload() {
             payload @ TransactionPayload::Script(_)
-            | payload @ TransactionPayload::EntryFunction(_) => {
+            | payload @ TransactionPayload::EntryFunction(_)
+            | payload @ TransactionPayload::MultiAgentWithFeePayer(_) => {
                 self.0.execute_script_or_entry_function(
                     resolver,
                     session,