DRAFT: EIP-7708

src/ethereum/cancun/vm/__init__.py

@@ -19,15 +19,18 @@
 from ethereum_types.bytes import Bytes, Bytes0, Bytes32
 from ethereum_types.numeric import U64, U256, Uint
 
-from ethereum.crypto.hash import Hash32
+from ethereum.crypto.hash import Hash32, keccak256
 from ethereum.exceptions import EthereumException
+from ethereum.utils.byte import right_pad_zero_bytes
 
 from ..blocks import Log
 from ..fork_types import Address, VersionedHash
 from ..state import State, TransientStorage, account_exists_and_is_empty
 from .precompiled_contracts import RIPEMD160_ADDRESS
 
 __all__ = ("Environment", "Evm", "Message")
+# Magic number for transaction logs converted to Keccak Hash
+MAGIC_LOG_KHASH = keccak256(b"42")
 
 
 @dataclass
@@ -150,3 +153,40 @@ def incorporate_child_on_error(evm: Evm, child_evm: Evm) -> None:
         ):
             evm.touched_accounts.add(RIPEMD160_ADDRESS)
     evm.gas_left += child_evm.gas_left
+
+
+def transfer_log(
+    evm: Evm,
+    sender: Address,
+    recipient: Address,
+    transfer_amount: U256,
+) -> None:
+    """
+    Main functional unit satisfying EIP-7708
+
+    Parameters
+    ----------
+    evm :
+        The state of the ethereum virtual machine
+    sender :
+        The account address sending the transfer
+    recipient :
+        The address of the transfer recipient account
+    transfer_amount :
+        The amount of ETH transacted
+    """
+    # We need to pre-pad the Address correctly before converting,
+    # otherwise it will throw because the lengths are not the same
+    padded_sender = right_pad_zero_bytes(sender, 12)
+    padded_recipient = right_pad_zero_bytes(recipient, 12)
+    log_entry = Log(
+        address=evm.message.current_target,
+        topics=(
+            MAGIC_LOG_KHASH,  # noqa: SC200
+            Hash32(padded_sender),
+            Hash32(padded_recipient),
+        ),
+        data=transfer_amount.to_be_bytes(),
+    )
+
+    evm.logs = evm.logs + (log_entry,)

src/ethereum/cancun/vm/instructions/system.py

@@ -11,6 +11,7 @@
 
 Implementations of the EVM system related instructions.
 """
+
 from ethereum_types.bytes import Bytes0
 from ethereum_types.numeric import U256, Uint
 
@@ -37,6 +38,7 @@
     Message,
     incorporate_child_on_error,
     incorporate_child_on_success,
+    transfer_log,
 )
 from ..exceptions import OutOfGasError, Revert, WriteInStaticContext
 from ..gas import (
@@ -380,9 +382,11 @@ def call(evm: Evm) -> None:
         access_gas_cost + create_gas_cost + transfer_gas_cost,
     )
     charge_gas(evm, message_call_gas.cost + extend_memory.cost)
+
     if evm.message.is_static and value != U256(0):
         raise WriteInStaticContext
     evm.memory += b"\x00" * extend_memory.expand_by
+
     sender_balance = get_account(
         evm.env.state, evm.message.current_target
     ).balance
@@ -405,6 +409,12 @@ def call(evm: Evm) -> None:
             memory_output_start_position,
             memory_output_size,
         )
+        transfer_log(
+            evm,
+            evm.message.current_target,
+            to,
+            value,
+        )
 
     # PROGRAM COUNTER
     evm.pc += Uint(1)
@@ -522,6 +532,13 @@ def selfdestruct(evm: Evm) -> None:
         originator_balance,
     )
 
+    transfer_log(
+        evm,
+        evm.message.current_target,
+        beneficiary,
+        originator_balance,
+    )
+
     # register account for deletion only if it was created
     # in the same transaction
     if originator in evm.env.state.created_accounts:

src/ethereum/cancun/vm/interpreter.py

@@ -49,7 +49,7 @@
 from ..vm import Message
 from ..vm.gas import GAS_CODE_DEPOSIT, charge_gas
 from ..vm.precompiled_contracts.mapping import PRE_COMPILED_CONTRACTS
-from . import Environment, Evm
+from . import Environment, Evm, transfer_log
 from .exceptions import (
     AddressCollision,
     ExceptionalHalt,
@@ -286,6 +286,13 @@ def execute_code(message: Message, env: Environment) -> Evm:
         accessed_addresses=message.accessed_addresses,
         accessed_storage_keys=message.accessed_storage_keys,
     )
+    transfer_log(
+        evm,
+        message.current_target,
+        message.caller,
+        message.value,
+    )
+
     try:
         if evm.message.code_address in PRE_COMPILED_CONTRACTS:
             evm_trace(evm, PrecompileStart(evm.message.code_address))