# Transactions This section defines the `sdk.Msg` concrete types that result in the state transitions defined on the previous section. ### `MsgEthereumTx` An EVM state transition can be achieved by using the `MsgEthereumTx`. This message encapsulates an Ethereum transaction data (`TxData`) as a `sdk.Msg`. It contains the necessary transaction data fields. Note, that the `MsgEthereumTx` implements both the [`sdk.Msg` ](https://github.com/cosmos/cosmos-sdk/blob/v0.39.2/types/tx_msg.go#L7-L29)and [`sdk.Tx` ](https://github.com/cosmos/cosmos-sdk/blob/v0.39.2/types/tx_msg.go#L33-L41)interfaces. Normally, SDK messages only implement the former, while the latter is a group of messages bundled together. ```go type MsgEthereumTx struct { // inner transaction data Data *types.Any `protobuf:"bytes,1,opt,name=data,proto3" json:"data,omitempty"` // DEPRECATED: encoded storage size of the transaction Size_ float64 `protobuf:"fixed64,2,opt,name=size,proto3" json:"-"` // transaction hash in hex format Hash string `protobuf:"bytes,3,opt,name=hash,proto3" json:"hash,omitempty" rlp:"-"` // ethereum signer address in hex format. This address value is checked // against the address derived from the signature (V, R, S) using the // secp256k1 elliptic curve From string `protobuf:"bytes,4,opt,name=from,proto3" json:"from,omitempty"` } ``` This message field validation is expected to fail if: * `From` field is defined and the address is invalid * `TxData` stateless validation fails The transaction execution is expected to fail if: * Any of the custom `AnteHandler` Ethereum decorators checks fail: * Minimum gas amount requirements for transaction * Tx sender account doesn't exist or hasn't enough balance for fees * Account sequence doesn't match the transaction `Data.AccountNonce` * Message signature verification fails * EVM contract creation (i.e `evm.Create`) fails, or `evm.Call` fails #### Conversion The `MsgEthreumTx` can be converted to the go-ethereum `Transaction` and `Message` types in order to create and call evm contracts. ```go // AsTransaction creates an Ethereum Transaction type from the msg fields func (msg MsgEthereumTx) AsTransaction() *ethtypes.Transaction { txData, err := UnpackTxData(msg.Data) if err != nil { return nil } return ethtypes.NewTx(txData.AsEthereumData()) } // AsMessage returns the transaction as a core.Message. func (tx *Transaction) AsMessage(s Signer, baseFee *big.Int) (Message, error) { msg := Message{ nonce: tx.Nonce(), gasLimit: tx.Gas(), gasPrice: new(big.Int).Set(tx.GasPrice()), gasFeeCap: new(big.Int).Set(tx.GasFeeCap()), gasTipCap: new(big.Int).Set(tx.GasTipCap()), to: tx.To(), amount: tx.Value(), data: tx.Data(), accessList: tx.AccessList(), isFake: false, } // If baseFee provided, set gasPrice to effectiveGasPrice. if baseFee != nil { msg.gasPrice = math.BigMin(msg.gasPrice.Add(msg.gasTipCap, baseFee), msg.gasFeeCap) } var err error msg.from, err = Sender(s, tx) return msg, err } ``` #### Signing In order for the signature verification to be valid, the `TxData` must contain the `v | r | s` values from the `Signer`. Sign calculates a secp256k1 ECDSA signature and signs the transaction. It takes a keyring signer and the chainID to sign an Ethereum transaction according to EIP155 standard. This method mutates the transaction as it populates the V, R, S fields of the Transaction's Signature. The function will fail if the sender address is not defined for the msg or if the sender is not registered on the keyring. ```go // Sign calculates a secp256k1 ECDSA signature and signs the transaction. It // takes a keyring signer and the chainID to sign an Ethereum transaction according to // EIP155 standard. // This method mutates the transaction as it populates the V, R, S // fields of the Transaction's Signature. // The function will fail if the sender address is not defined for the msg or if // the sender is not registered on the keyring func (msg *MsgEthereumTx) Sign(ethSigner ethtypes.Signer, keyringSigner keyring.Signer) error { from := msg.GetFrom() if from.Empty() { return fmt.Errorf("sender address not defined for message") } tx := msg.AsTransaction() txHash := ethSigner.Hash(tx) sig, _, err := keyringSigner.SignByAddress(from, txHash.Bytes()) if err != nil { return err } tx, err = tx.WithSignature(ethSigner, sig) if err != nil { return err } msg.FromEthereumTx(tx) return nil } ``` ### TxData The `MsgEthereumTx` supports the 3 valid Ethereum transaction data types from go-ethereum: `LegacyTx`, `AccessListTx` and `DynamicFeeTx`. These types are defined as protobuf messages and packed into a `proto.Any` interface type in the `MsgEthereumTx` field. * `LegacyTx`: [EIP-155 ](https://github.com/ethereum/EIPs/blob/master/EIPS/eip-155.md)transaction type * `DynamicFeeTx`: [EIP-1559 ](https://eips.ethereum.org/EIPS/eip-1559)transaction type. Enabled by London hard fork block * `AccessListTx`: [EIP-2930 ](https://eips.ethereum.org/EIPS/eip-2930)transaction type. Enabled by Berlin hard fork block #### `LegacyTx` The transaction data of regular Ethereum transactions. ```go type LegacyTx struct { // nonce corresponds to the account nonce (transaction sequence). Nonce uint64 `protobuf:"varint,1,opt,name=nonce,proto3" json:"nonce,omitempty"` // gas price defines the value for each gas unit GasPrice *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,2,opt,name=gas_price,json=gasPrice,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"gas_price,omitempty"` // gas defines the gas limit defined for the transaction. GasLimit uint64 `protobuf:"varint,3,opt,name=gas,proto3" json:"gas,omitempty"` // hex formatted address of the recipient To string `protobuf:"bytes,4,opt,name=to,proto3" json:"to,omitempty"` // value defines the unsigned integer value of the transaction amount. Amount *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,5,opt,name=value,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"value,omitempty"` // input defines the data payload bytes of the transaction. Data []byte `protobuf:"bytes,6,opt,name=data,proto3" json:"data,omitempty"` // v defines the signature value V []byte `protobuf:"bytes,7,opt,name=v,proto3" json:"v,omitempty"` // r defines the signature value R []byte `protobuf:"bytes,8,opt,name=r,proto3" json:"r,omitempty"` // s define the signature value S []byte `protobuf:"bytes,9,opt,name=s,proto3" json:"s,omitempty"` } ``` This message field validation is expected to fail if: * `GasPrice` is invalid (`nil` , negaitve or out of int256 bound) * `Fee` (gasprice \* gaslimit) is invalid * `Amount` is invalid (negaitve or out of int256 bound) * `To` address is invalid (non valid ethereum hex address) #### `DynamicFeeTx` The transaction data of EIP-1559 dynamic fee transactions. ```go type DynamicFeeTx struct { // destination EVM chain ID ChainID *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,1,opt,name=chain_id,json=chainId,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"chainID"` // nonce corresponds to the account nonce (transaction sequence). Nonce uint64 `protobuf:"varint,2,opt,name=nonce,proto3" json:"nonce,omitempty"` // gas tip cap defines the max value for the gas tip GasTipCap *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,3,opt,name=gas_tip_cap,json=gasTipCap,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"gas_tip_cap,omitempty"` // gas fee cap defines the max value for the gas fee GasFeeCap *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,4,opt,name=gas_fee_cap,json=gasFeeCap,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"gas_fee_cap,omitempty"` // gas defines the gas limit defined for the transaction. GasLimit uint64 `protobuf:"varint,5,opt,name=gas,proto3" json:"gas,omitempty"` // hex formatted address of the recipient To string `protobuf:"bytes,6,opt,name=to,proto3" json:"to,omitempty"` // value defines the the transaction amount. Amount *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,7,opt,name=value,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"value,omitempty"` // input defines the data payload bytes of the transaction. Data []byte `protobuf:"bytes,8,opt,name=data,proto3" json:"data,omitempty"` Accesses AccessList `protobuf:"bytes,9,rep,name=accesses,proto3,castrepeated=AccessList" json:"accessList"` // v defines the signature value V []byte `protobuf:"bytes,10,opt,name=v,proto3" json:"v,omitempty"` // r defines the signature value R []byte `protobuf:"bytes,11,opt,name=r,proto3" json:"r,omitempty"` // s define the signature value S []byte `protobuf:"bytes,12,opt,name=s,proto3" json:"s,omitempty"` } ``` This message field validation is expected to fail if: * `GasTipCap` is invalid (`nil` , negative or overflows int256) * `GasFeeCap` is invalid (`nil` , negative or overflows int256) * `GasFeeCap` is less than `GasTipCap` * `Fee` (gas price \* gas limit) is invalid (overflows int256) * `Amount` is invalid (negative or overflows int256) * `To` address is invalid (non-valid ethereum hex address) * `ChainID` is `nil` #### `AccessListTx` The transaction data of EIP-2930 access list transactions. ```go type AccessListTx struct { // destination EVM chain ID ChainID *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,1,opt,name=chain_id,json=chainId,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"chainID"` // nonce corresponds to the account nonce (transaction sequence). Nonce uint64 `protobuf:"varint,2,opt,name=nonce,proto3" json:"nonce,omitempty"` // gas price defines the value for each gas unit GasPrice *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,3,opt,name=gas_price,json=gasPrice,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"gas_price,omitempty"` // gas defines the gas limit defined for the transaction. GasLimit uint64 `protobuf:"varint,4,opt,name=gas,proto3" json:"gas,omitempty"` // hex formatted address of the recipient To string `protobuf:"bytes,5,opt,name=to,proto3" json:"to,omitempty"` // value defines the unsigned integer value of the transaction amount. Amount *github_com_cosmos_cosmos_sdk_types.Int `protobuf:"bytes,6,opt,name=value,proto3,customtype=github.com/cosmos/cosmos-sdk/types.Int" json:"value,omitempty"` // input defines the data payload bytes of the transaction. Data []byte `protobuf:"bytes,7,opt,name=data,proto3" json:"data,omitempty"` Accesses AccessList `protobuf:"bytes,8,rep,name=accesses,proto3,castrepeated=AccessList" json:"accessList"` // v defines the signature value V []byte `protobuf:"bytes,9,opt,name=v,proto3" json:"v,omitempty"` // r defines the signature value R []byte `protobuf:"bytes,10,opt,name=r,proto3" json:"r,omitempty"` // s define the signature value S []byte `protobuf:"bytes,11,opt,name=s,proto3" json:"s,omitempty"` } ``` This message field validation is expected to fail if: * `GasPrice` is invalid (`nil` , negative or overflows int256) * `Fee` (gas price \* gas limit) is invalid (overflows int256) * `Amount` is invalid (negative or overflows int256) * `To` address is invalid (non-valid ethereum hex address) * `ChainID` is `nil` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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