From 8e6bead4784d625696b9967230b84834adc50e9f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Kripalani?= <raul@protocol.ai>
Date: Thu, 12 Jan 2023 15:58:30 +0000
Subject: [PATCH] cleanup ethtypes.{Try=>}EthAddressFromFilecoinAddress.

---
 chain/types/ethtypes/eth_types.go | 72 +++++++++++++------------------
 node/impl/full/eth.go             | 23 ++++------
 2 files changed, 38 insertions(+), 57 deletions(-)

diff --git a/chain/types/ethtypes/eth_types.go b/chain/types/ethtypes/eth_types.go
index 8cf931bf03a..a4f8fb94dd3 100644
--- a/chain/types/ethtypes/eth_types.go
+++ b/chain/types/ethtypes/eth_types.go
@@ -5,6 +5,7 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"encoding/json"
+	"errors"
 	"fmt"
 	mathbig "math/big"
 	"strconv"
@@ -30,6 +31,8 @@ var (
 	EthTopic4 = "topic4"
 )
 
+var ErrInvalidAddress = errors.New("invalid Filecoin Eth address")
+
 type EthUint64 uint64
 
 func (e EthUint64) MarshalJSON() ([]byte, error) {
@@ -249,16 +252,28 @@ func EthAddressFromPubKey(pubk []byte) ([]byte, error) {
 }
 
 func EthAddressFromFilecoinAddress(addr address.Address) (EthAddress, error) {
-	ethAddr, ok, err := TryEthAddressFromFilecoinAddress(addr, true)
-	if err != nil {
-		return EthAddress{}, xerrors.Errorf("failed to try converting filecoin to eth addr: %w", err)
-	}
-
-	if !ok {
-		return EthAddress{}, xerrors.Errorf("failed to convert filecoin address %s to an equivalent eth address", addr)
+	switch addr.Protocol() {
+	case address.ID:
+		id, err := address.IDFromAddress(addr)
+		if err != nil {
+			return EthAddress{}, err
+		}
+		var ethaddr EthAddress
+		ethaddr[0] = 0xff
+		binary.BigEndian.PutUint64(ethaddr[12:], id)
+		return ethaddr, nil
+	case address.Delegated:
+		payload := addr.Payload()
+		namespace, n, err := varint.FromUvarint(payload)
+		if err != nil {
+			return EthAddress{}, xerrors.Errorf("invalid delegated address namespace in: %s", addr)
+		}
+		payload = payload[n:]
+		if namespace == builtintypes.EthereumAddressManagerActorID {
+			return CastEthAddress(payload)
+		}
 	}
-
-	return ethAddr, nil
+	return EthAddress{}, ErrInvalidAddress
 }
 
 // ParseEthAddress parses an Ethereum address from a hex string.
@@ -303,9 +318,13 @@ func (ea *EthAddress) UnmarshalJSON(b []byte) error {
 	return nil
 }
 
-func (ea EthAddress) ToFilecoinAddress() (address.Address, error) {
+func (ea EthAddress) IsMaskedID() bool {
 	idmask := [12]byte{0xff}
-	if bytes.Equal(ea[:12], idmask[:]) {
+	return bytes.Equal(ea[:12], idmask[:])
+}
+
+func (ea EthAddress) ToFilecoinAddress() (address.Address, error) {
+	if ea.IsMaskedID() {
 		// This is a masked ID address.
 		id := binary.BigEndian.Uint64(ea[12:])
 		return address.NewIDAddress(id)
@@ -321,37 +340,6 @@ func (ea EthAddress) ToFilecoinAddress() (address.Address, error) {
 	return addr, nil
 }
 
-// This API assumes that if an ID address is passed in, it doesn't have an equivalent
-// delegated address
-func TryEthAddressFromFilecoinAddress(addr address.Address, allowId bool) (EthAddress, bool, error) {
-	switch addr.Protocol() {
-	case address.ID:
-		if !allowId {
-			return EthAddress{}, false, nil
-		}
-		id, err := address.IDFromAddress(addr)
-		if err != nil {
-			return EthAddress{}, false, err
-		}
-		var ethaddr EthAddress
-		ethaddr[0] = 0xff
-		binary.BigEndian.PutUint64(ethaddr[12:], id)
-		return ethaddr, true, nil
-	case address.Delegated:
-		payload := addr.Payload()
-		namespace, n, err := varint.FromUvarint(payload)
-		if err != nil {
-			return EthAddress{}, false, xerrors.Errorf("invalid delegated address namespace in: %s", addr)
-		}
-		payload = payload[n:]
-		if namespace == builtintypes.EthereumAddressManagerActorID {
-			addr, err := CastEthAddress(payload)
-			return addr, err == nil, err
-		}
-	}
-	return EthAddress{}, false, nil
-}
-
 type EthHash [EthHashLength]byte
 
 func (h EthHash) MarshalJSON() ([]byte, error) {
diff --git a/node/impl/full/eth.go b/node/impl/full/eth.go
index e402149a650..76c3f592351 100644
--- a/node/impl/full/eth.go
+++ b/node/impl/full/eth.go
@@ -1431,30 +1431,23 @@ func newEthBlockFromFilecoinTipSet(ctx context.Context, ts *types.TipSet, fullTx
 //     use that ID to form the masked ID address.
 //  4. Otherwise, we fetch the actor's ID from the state tree and form the masked ID with it.
 func lookupEthAddress(ctx context.Context, addr address.Address, sa StateAPI) (ethtypes.EthAddress, error) {
-	// Attempt to convert directly.
-	if ethAddr, ok, err := ethtypes.TryEthAddressFromFilecoinAddress(addr, false); err != nil {
-		return ethtypes.EthAddress{}, err
-	} else if ok {
+	// Attempt to convert directly, if it's an f4 address.
+	ethAddr, err := ethtypes.EthAddressFromFilecoinAddress(addr)
+	if err == nil && !ethAddr.IsMaskedID() {
 		return ethAddr, nil
 	}
 
-	// Lookup on the target actor.
-	actor, err := sa.StateGetActor(ctx, addr, types.EmptyTSK)
-	if err != nil {
+	// Lookup on the target actor and try to get an f410 address.
+	if actor, err := sa.StateGetActor(ctx, addr, types.EmptyTSK); err != nil {
 		return ethtypes.EthAddress{}, err
-	}
-	if actor.Address != nil {
-		if ethAddr, ok, err := ethtypes.TryEthAddressFromFilecoinAddress(*actor.Address, false); err != nil {
-			return ethtypes.EthAddress{}, err
-		} else if ok {
+	} else if actor.Address != nil {
+		if ethAddr, err := ethtypes.EthAddressFromFilecoinAddress(*actor.Address); err == nil && !ethAddr.IsMaskedID() {
 			return ethAddr, nil
 		}
 	}
 
 	// Check if we already have an ID addr, and use it if possible.
-	if ethAddr, ok, err := ethtypes.TryEthAddressFromFilecoinAddress(addr, true); err != nil {
-		return ethtypes.EthAddress{}, err
-	} else if ok {
+	if err == nil && ethAddr.IsMaskedID() {
 		return ethAddr, nil
 	}