Flatten EIP-7002 withdrawal requests encoding (#12138)

In summary, does away with a lot of earlier complexities related to
parsing and encoding withdrawal requests. These are now just byte
strings, essentially

Refer to the following
- ethereum/EIPs#8855 (flat requests format
update for EIP-7002)
-
https://github.com/ethereum/EIPs/pull/8934/files#diff-70472fac1debb567783ce13873323261713f3ce488a26a5c3769a9193f4a7e27R596
(Address update)

Needs interface update -
erigontech/interfaces#234

(Tasks board - #12106)

consensus/misc/eip7002.go

@@ -17,9 +17,6 @@
 package misc
 
 import (
-	"encoding/binary"
-
-	"github.com/erigontech/erigon-lib/common"
 	"github.com/erigontech/erigon-lib/log/v3"
 	"github.com/erigontech/erigon/consensus"
 	"github.com/erigontech/erigon/core/types"
@@ -30,93 +27,23 @@ import (
 // (May have to move it to config json later for cross-chain compatibility)
 // TODO @somnathb1 Probably not needed outside of EVM
 const (
-	ExcessWithdrawalReqsSlot        = 0
-	WithdrawalReqCountSlot          = 1
-	WithdrawalReqQueueHeadSlot      = 2
-	WithdrawalReqQueueTailSlot      = 3
-	WithdrawalReqQueueStorageOffset = 4
-	MaxWithdrawalReqsPerBlock       = 16
-	TargetWithdrawalReqsPerBlock    = 2
-	MinWithdrawalReqFee             = 1
-	WithdrawalReqFeeUpdFraction     = 17
+	WithdrawalRequestDataLen = 76 // addr + pubkey + amt
 )
 
-// const abiStr = `[
-// 	{
-// 		"inputs": [],
-// 		"name": "read_withdrawal_requests",
-// 		"outputs": [
-// 			{
-// 				"components": [
-// 					{
-// 						"internalType": "bytes20",
-// 						"name": "sourceAddress",
-// 						"type": "bytes20"
-// 					},
-// 					{
-// 						"internalType": "bytes32",
-// 						"name": "validatorPubKey1",
-// 						"type": "bytes32"
-// 					},
-// 					{
-// 						"internalType": "bytes16",
-// 						"name": "validatorPubKey2",
-// 						"type": "bytes16"
-// 					},
-// 					{
-// 						"internalType": "uint64",
-// 						"name": "amount",
-// 						"type": "uint64"
-// 					}
-// 				],
-// 				"internalType": "struct WithdrawalContract.ValidatorWithdrawalRequest[]",
-// 				"name": "",
-// 				"type": "tuple[]"
-// 			}
-// 		],
-// 		"stateMutability": "nonpayable",
-// 		"type": "function"
-// 	}
-// ]`
-
 func DequeueWithdrawalRequests7002(syscall consensus.SystemCall) types.Requests {
 	res, err := syscall(params.WithdrawalRequestAddress, nil)
 	if err != nil {
 		log.Warn("Err with syscall to WithdrawalRequestAddress", "err", err)
 		return nil
 	}
-	// Parse out the exits - using the bytes array returned
+	// Just append the contract outputs
 	var reqs types.Requests
-	lenPerReq := 20 + 48 + 8 // addr + pubkey + amt
-	for i := 0; i <= len(res)-lenPerReq; i += lenPerReq {
-		var pubkey [48]byte
-		copy(pubkey[:], res[i+20:i+68])
+	for i := 0; i <= len(res)-WithdrawalRequestDataLen; i += WithdrawalRequestDataLen {
+
 		wr := &types.WithdrawalRequest{
-			SourceAddress:   common.BytesToAddress(res[i : i+20]),
-			ValidatorPubkey: pubkey,
-			Amount:          binary.BigEndian.Uint64(res[i+68:]),
+			RequestData: [WithdrawalRequestDataLen]byte(res[i : i+WithdrawalRequestDataLen]),
 		}
 		reqs = append(reqs, wr)
 	}
 	return reqs
-
-	// Alternatively unpack using the abi methods
-	// wAbi, _ := abi.JSON(strings.NewReader(abiStr))
-	// wAbi.Unpack("read_withdrawal_requests", wrs)
-
-	// type R struct {
-	// 	sourceAddress [20]byte
-	// 	validatorPubKey1 [32] byte
-	// 	validatorPubKey2 [16] byte
-	// 	amount uint64
-	// }
-	// Ret := make([]R, 0)
-	// wAbi.UnpackIntoInterface(Ret, "read_withdrawal_requests", wrs)
-
-	// reqs := make(types.Requests, 0)
-
-	// for r := range(Ret) {
-	// 	req := types.NewRequest(Ret)
-	// 	reqs = append(reqs, types.NewRequest())
-	// }
 }

core/types/encdec_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/holiman/uint256"
 
 	libcommon "github.com/erigontech/erigon-lib/common"
+	"github.com/erigontech/erigon-lib/common/hexutility"
 	types2 "github.com/erigontech/erigon-lib/types"
 	"github.com/erigontech/erigon/rlp"
 )
@@ -88,9 +89,7 @@ func (tr *TRand) RandWithdrawal() *Withdrawal {
 
 func (tr *TRand) RandWithdrawalRequest() *WithdrawalRequest {
 	return &WithdrawalRequest{
-		SourceAddress:   [20]byte(tr.RandBytes(20)),
-		ValidatorPubkey: [48]byte(tr.RandBytes(48)),
-		Amount:          *tr.RandUint64(),
+		RequestData: [WithdrawalRequestDataLen]byte(tr.RandBytes(WithdrawalRequestDataLen)),
 	}
 }
 
@@ -413,9 +412,7 @@ func compareDeposits(t *testing.T, a, b *DepositRequest) {
 }
 
 func compareWithdrawalRequests(t *testing.T, a, b *WithdrawalRequest) {
-	check(t, "WithdrawalRequest.SourceAddress", a.SourceAddress, b.SourceAddress)
-	check(t, "WithdrawalRequest.ValidatorPubkey", a.ValidatorPubkey, b.ValidatorPubkey)
-	check(t, "WithdrawalRequest.Amount", a.Amount, b.Amount)
+	check(t, "WithdrawalRequest.Amount", a.RequestData, b.RequestData)
 }
 
 func compareConsolidationRequests(t *testing.T, a, b *ConsolidationRequest) {
@@ -616,57 +613,21 @@ func TestConsolidationReqsEncodeDecode(t *testing.T) {
 
 func TestWithdrawalReqsEncodeDecode(t *testing.T) {
 	wx1 := WithdrawalRequest{
-		SourceAddress:   libcommon.HexToAddress("0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b"),
-		ValidatorPubkey: [48]byte{},
-		Amount:          0,
+		RequestData: [WithdrawalRequestDataLen]byte(hexutility.MustDecodeHex("0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001fefefefefefefefe")),
 	}
-	wx1.ValidatorPubkey[47] = 0x01
 	wx2 := WithdrawalRequest{
-		SourceAddress:   libcommon.HexToAddress("0x8a0a19589531694250d570040a0c4b74576919b8"),
-		ValidatorPubkey: [48]byte{},
-		Amount:          0xfffffffffffffffe,
-	}
-	wx2.ValidatorPubkey[47] = 0x02
-	wxs := append(Requests{}, &wx1, &wx2)
-
-	root := DeriveSha(wxs)
-	if root.String() != "0x143e24a803c0dc2ae5381184ad5fe9e45ac2c82c671bc3eafdc090642fc16501" {
-		t.Errorf("Root mismatch %s", root.String())
+		RequestData: [WithdrawalRequestDataLen]byte(hexutility.MustDecodeHex("0x8a0a19589531694250d570040a0c4b74576919b8000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001fefefefefefefefe")),
 	}
 
 	var wx3, wx4 WithdrawalRequest
 	var buf1, buf2 bytes.Buffer
 	wx1.EncodeRLP(&buf1)
 	wx2.EncodeRLP(&buf2)
+
 	wx3.DecodeRLP(buf1.Bytes())
 	wx4.DecodeRLP(buf2.Bytes())
-	wxs = Requests{}
-	wxs = append(wxs, &wx3, &wx4)
-	root = DeriveSha(wxs)
-	if root.String() != "0x143e24a803c0dc2ae5381184ad5fe9e45ac2c82c671bc3eafdc090642fc16501" {
-		t.Errorf("Root mismatch %s", root.String())
-	}
-
-	/*
-		// Breakdown of block encoding with withdrawal requests - expected
-		c0c0f8a0
-
-		b84a
-		01
-		f84794
-		a94f5374fce5edbc8e2a8697c15331677e6ebf0b
-		b0
-		000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001
-		80
-
-		b852
-		01
-		f84f94
-		8a0a19589531694250d570040a0c4b74576919b8
-		b0
-		000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002
-		88
-		fffffffffffffffe
-	*/
 
+	if wx1.RequestData != wx3.RequestData || wx2.RequestData != wx4.RequestData {
+		t.Errorf("error: incorrect encode/decode for WithdrawalRequest")
+	}
 }

core/types/request.go

@@ -31,6 +31,7 @@ import (
 const WithdrawalRequestType byte = 0x01
 const DepositRequestType byte = 0x00
 const ConsolidationRequestType byte = 0x02
+const WithdrawalRequestDataLen = 76 // addr + pubkey + amt
 
 type Request interface {
 	EncodeRLP(io.Writer) error

core/types/withdrawal_request.go

@@ -22,24 +22,16 @@ import (
 	"errors"
 	"io"
 
-	libcommon "github.com/erigontech/erigon-lib/common"
-	"github.com/erigontech/erigon-lib/common/hexutil"
 	"github.com/erigontech/erigon-lib/common/hexutility"
-	rlp2 "github.com/erigontech/erigon-lib/rlp"
-	"github.com/erigontech/erigon/rlp"
 )
 
 // EIP-7002 Withdrawal Request see https://github.com/ethereum/EIPs/blob/master/EIPS/eip-7002.md
 type WithdrawalRequest struct {
-	SourceAddress   libcommon.Address
-	ValidatorPubkey [BLSPubKeyLen]byte // bls
-	Amount          uint64
+	RequestData [WithdrawalRequestDataLen]byte
 }
 
 type WithdrawalRequestJson struct {
-	SourceAddress   libcommon.Address `json:"sourceAddress"`
-	ValidatorPubkey string            `json:"validatorPubkey"`
-	Amount          hexutil.Uint64    `json:"amount"`
+	RequestData string
 }
 
 func (w *WithdrawalRequest) RequestType() byte {
@@ -48,53 +40,42 @@ func (w *WithdrawalRequest) RequestType() byte {
 
 // encodingSize implements RequestData.
 func (w *WithdrawalRequest) EncodingSize() (encodingSize int) {
-	encodingSize += 70 // 1 + 20 + 1 + 48 (0x80 + addrSize, 0x80 + BLSPubKeyLen)
-	encodingSize++
-	encodingSize += rlp.IntLenExcludingHead(w.Amount)
-	encodingSize += rlp2.ListPrefixLen(encodingSize)
-	encodingSize += 1 // RequestType
-	return
+	return WithdrawalRequestDataLen + 1
 }
 func (w *WithdrawalRequest) EncodeRLP(b io.Writer) (err error) {
-	var buf bytes.Buffer
-	bb := make([]byte, 10)
-	if err = rlp.Encode(&buf, w.SourceAddress); err != nil {
-		return err
-	}
-	if err = rlp.Encode(&buf, w.ValidatorPubkey); err != nil {
+	if _, err = b.Write([]byte{WithdrawalRequestType}); err != nil {
 		return err
 	}
-	if err = rlp.EncodeInt(w.Amount, &buf, bb); err != nil {
+	if _, err = b.Write(w.RequestData[:]); err != nil {
 		return err
 	}
-	rlp2.EncodeListPrefix(buf.Len(), bb)
+	return
+}
 
-	if _, err = b.Write([]byte{WithdrawalRequestType}); err != nil {
-		return err
-	}
-	if _, err = b.Write(bb[0:2]); err != nil {
-		return err
+func (w *WithdrawalRequest) Encode() []byte {
+	if w == nil {
+		return nil
 	}
-	if _, err = b.Write(buf.Bytes()); err != nil {
-		return err
+	return append([]byte{WithdrawalRequestType}, w.RequestData[:]...)
+}
+
+func (w *WithdrawalRequest) DecodeRLP(input []byte) error {
+	if len(input) != WithdrawalRequestDataLen+1 {
+		return errors.New("Incorrect size for decoding WithdrawalRequest RLP")
 	}
-	return
+	w.RequestData = [76]byte(input[1:])
+	return nil
 }
 
-func (w *WithdrawalRequest) DecodeRLP(input []byte) error { return rlp.DecodeBytes(input[1:], w) }
 func (w *WithdrawalRequest) copy() Request {
 	return &WithdrawalRequest{
-		SourceAddress:   w.SourceAddress,
-		ValidatorPubkey: w.ValidatorPubkey,
-		Amount:          w.Amount,
+		RequestData: [WithdrawalRequestDataLen]byte(bytes.Clone(w.RequestData[:])),
 	}
 }
 
 func (w *WithdrawalRequest) MarshalJSON() ([]byte, error) {
 	tt := WithdrawalRequestJson{
-		SourceAddress:   w.SourceAddress,
-		ValidatorPubkey: hexutility.Encode(w.ValidatorPubkey[:]),
-		Amount:          hexutil.Uint64(w.Amount),
+		RequestData: hexutility.Encode(w.RequestData[:]),
 	}
 	return json.Marshal(tt)
 }
@@ -105,18 +86,11 @@ func (w *WithdrawalRequest) UnmarshalJSON(input []byte) error {
 	if err != nil {
 		return err
 	}
-
-	validatorKey, err := hexutil.Decode(tt.ValidatorPubkey)
-	if err != nil {
-		return err
-	}
-	if len(validatorKey) != BLSPubKeyLen {
-		return errors.New("WithdrawalRequest ValidatorPubkey len after UnmarshalJSON doesn't match BLSKeyLen")
+	if len(tt.RequestData) != WithdrawalRequestDataLen {
+		return errors.New("Cannot unmarshal request data, length mismatch")
 	}
 
-	w.ValidatorPubkey = [BLSPubKeyLen]byte(validatorKey)
-	w.Amount = tt.Amount.Uint64()
-	w.SourceAddress = tt.SourceAddress
+	w.RequestData = [WithdrawalRequestDataLen]byte(hexutility.MustDecodeString(tt.RequestData))
 	return nil
 }
 

erigon-lib/go.mod

@@ -4,7 +4,7 @@ go 1.22.0
 
 require (
 	github.com/erigontech/erigon-snapshot v1.3.1-0.20240814160410-2ce37904b978
-	github.com/erigontech/interfaces v0.0.0-20240912071218-97d86b41623a
+	github.com/erigontech/interfaces v0.0.0-20240930141537-21d2f6889ec4
 	github.com/erigontech/mdbx-go v0.38.4
 	github.com/erigontech/secp256k1 v1.1.0
 	github.com/rs/dnscache v0.0.0-20211102005908-e0241e321417

erigon-lib/go.sum

@@ -148,8 +148,8 @@ github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1m
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
 github.com/erigontech/erigon-snapshot v1.3.1-0.20240814160410-2ce37904b978 h1:7ECOf7Us3+/706WGZXIX84qQc6zmxQby8fGbFLiqFlU=
 github.com/erigontech/erigon-snapshot v1.3.1-0.20240814160410-2ce37904b978/go.mod h1:ooHlCl+eEYzebiPu+FP6Q6SpPUeMADn8Jxabv3IKb9M=
-github.com/erigontech/interfaces v0.0.0-20240912071218-97d86b41623a h1:8SkMr0APaj4LiviMVfXHRqNgWmsl8mVnNb/ioMzRedE=
-github.com/erigontech/interfaces v0.0.0-20240912071218-97d86b41623a/go.mod h1:N7OUkhkcagp9+7yb4ycHsG2VWCOmuJ1ONBecJshxtLE=
+github.com/erigontech/interfaces v0.0.0-20240930141537-21d2f6889ec4 h1:MFWfaE+BwmFXfNfwwuyeNImS16HIsDGB0q3u7nCpIhY=
+github.com/erigontech/interfaces v0.0.0-20240930141537-21d2f6889ec4/go.mod h1:N7OUkhkcagp9+7yb4ycHsG2VWCOmuJ1ONBecJshxtLE=
 github.com/erigontech/mdbx-go v0.38.4 h1:S9T7mTe9KPcFe4dOoOtVdI6gPzht9y7wMnYfUBgrQLo=
 github.com/erigontech/mdbx-go v0.38.4/go.mod h1:IcOLQDPw3VM/asP6T5JVPPN4FHHgJtY16XfYjzWKVNI=
 github.com/erigontech/secp256k1 v1.1.0 h1:mO3YJMUSoASE15Ya//SoHiisptUhdXExuMUN1M0X9qY=