hermez-node/common/l1tx.go
common/l1tx.goRaw
1package common
2
3import (
4 "encoding/binary"
5 "fmt"
6 "math/big"
7
8 ethCommon "github.com/ethereum/go-ethereum/common"
9 "github.com/ethereum/go-ethereum/crypto"
10 "github.com/iden3/go-iden3-crypto/babyjub"
11)
12
13const (
14 // L1TxBytesLen is the length of the byte array that represents the L1Tx
15 L1TxBytesLen = 72
16 // L1CoordinatorTxBytesLen is the length of the byte array that represents the L1CoordinatorTx
17 L1CoordinatorTxBytesLen = 101
18)
19
20// L1Tx is a struct that represents a L1 tx
21type L1Tx struct {
22 // Stored in DB: mandatory fileds
23
24 // TxID (12 bytes) for L1Tx is:
25 // bytes: | 1 | 8 | 2 | 1 |
26 // values: | type | ToForgeL1TxsNum | Position | 0 (padding) |
27 // where type:
28 // - L1UserTx: 0
29 // - L1CoordinatorTx: 1
30 TxID TxID
31 ToForgeL1TxsNum *int64 // toForgeL1TxsNum in which the tx was forged / will be forged
32 Position int
33 UserOrigin bool // true if the tx was originated by a user, false if it was aoriginated by a coordinator. Note that this differ from the spec for implementation simplification purpposes
34 FromIdx *Idx // FromIdx is used by L1Tx/Deposit to indicate the Idx receiver of the L1Tx.LoadAmount (deposit)
35 FromEthAddr ethCommon.Address
36 FromBJJ *babyjub.PublicKey
37 ToIdx Idx // ToIdx is ignored in L1Tx/Deposit, but used in the L1Tx/DepositAndTransfer
38 TokenID TokenID
39 Amount *big.Int
40 LoadAmount *big.Int
41 EthBlockNum int64 // Ethereum Block Number in which this L1Tx was added to the queue
42 Type TxType
43 BatchNum *BatchNum
44 USD *float64
45 LoadAmountUSD *float64
46}
47
48// NewL1Tx returns the given L1Tx with the TxId & Type parameters calculated
49// from the L1Tx values
50func NewL1Tx(l1Tx *L1Tx) (*L1Tx, error) {
51 // calculate TxType
52 var txType TxType
53 if l1Tx.FromIdx == nil {
54 if l1Tx.ToIdx == Idx(0) {
55 txType = TxTypeCreateAccountDeposit
56 } else if l1Tx.ToIdx >= IdxUserThreshold {
57 txType = TxTypeCreateAccountDepositTransfer
58 } else {
59 return l1Tx, fmt.Errorf("Can not determine type of L1Tx, invalid ToIdx value: %d", l1Tx.ToIdx)
60 }
61 } else if *l1Tx.FromIdx >= IdxUserThreshold {
62 if l1Tx.ToIdx == Idx(0) {
63 txType = TxTypeDeposit
64 } else if l1Tx.ToIdx == Idx(1) {
65 txType = TxTypeExit
66 } else if l1Tx.ToIdx >= IdxUserThreshold {
67 if l1Tx.LoadAmount.Int64() == int64(0) {
68 txType = TxTypeForceTransfer
69 } else {
70 txType = TxTypeDepositTransfer
71 }
72 } else {
73 return l1Tx, fmt.Errorf("Can not determine type of L1Tx, invalid ToIdx value: %d", l1Tx.ToIdx)
74 }
75 } else {
76 return l1Tx, fmt.Errorf("Can not determine type of L1Tx, invalid FromIdx value: %d", l1Tx.FromIdx)
77 }
78
79 if l1Tx.Type != "" && l1Tx.Type != txType {
80 return l1Tx, fmt.Errorf("L1Tx.Type: %s, should be: %s", l1Tx.Type, txType)
81 }
82 l1Tx.Type = txType
83
84 txID, err := l1Tx.CalcTxID()
85 if err != nil {
86 return nil, err
87 }
88 l1Tx.TxID = *txID
89
90 return l1Tx, nil
91}
92
93func (l1Tx *L1Tx) CalcTxID() (*TxID, error) {
94 var txID TxID
95 if l1Tx.UserOrigin {
96 if l1Tx.ToForgeL1TxsNum == nil {
97 return nil, fmt.Errorf("L1Tx.UserOrigin == true && L1Tx.ToForgeL1TxsNum == nil")
98 }
99 txID[0] = TxIDPrefixL1UserTx
100 var toForgeL1TxsNumBytes [8]byte
101 binary.BigEndian.PutUint64(toForgeL1TxsNumBytes[:], uint64(*l1Tx.ToForgeL1TxsNum))
102 copy(txID[1:9], toForgeL1TxsNumBytes[:])
103 } else {
104 if l1Tx.BatchNum == nil {
105 return nil, fmt.Errorf("L1Tx.UserOrigin == false && L1Tx.BatchNum == nil")
106 }
107 txID[0] = TxIDPrefixL1CoordTx
108 var batchNumBytes [8]byte
109 binary.BigEndian.PutUint64(batchNumBytes[:], uint64(*l1Tx.BatchNum))
110 copy(txID[1:9], batchNumBytes[:])
111 }
112 var positionBytes [2]byte
113 binary.BigEndian.PutUint16(positionBytes[:], uint16(l1Tx.Position))
114 copy(txID[9:11], positionBytes[:])
115
116 return &txID, nil
117}
118
119// Tx returns a *Tx from the L1Tx
120func (tx *L1Tx) Tx() *Tx {
121 f := new(big.Float).SetInt(tx.Amount)
122 amountFloat, _ := f.Float64()
123 userOrigin := new(bool)
124 *userOrigin = tx.UserOrigin
125 fromEthAddr := new(ethCommon.Address)
126 *fromEthAddr = tx.FromEthAddr
127 toIdx := new(Idx)
128 *toIdx = tx.ToIdx
129 genericTx := &Tx{
130 IsL1: true,
131 TxID: tx.TxID,
132 Type: tx.Type,
133 Position: tx.Position,
134 FromIdx: tx.FromIdx,
135 ToIdx: toIdx,
136 Amount: tx.Amount,
137 AmountFloat: amountFloat,
138 TokenID: tx.TokenID,
139 ToForgeL1TxsNum: tx.ToForgeL1TxsNum,
140 UserOrigin: userOrigin,
141 FromEthAddr: fromEthAddr,
142 FromBJJ: tx.FromBJJ,
143 LoadAmount: tx.LoadAmount,
144 EthBlockNum: tx.EthBlockNum,
145 USD: tx.USD,
146 LoadAmountUSD: tx.LoadAmountUSD,
147 }
148 if tx.LoadAmount != nil {
149 lf := new(big.Float).SetInt(tx.LoadAmount)
150 loadAmountFloat, _ := lf.Float64()
151 genericTx.LoadAmountFloat = &loadAmountFloat
152 }
153 return genericTx
154}
155
156// Bytes encodes a L1Tx into []byte
157func (tx *L1Tx) Bytes() ([]byte, error) {
158 var b [L1TxBytesLen]byte
159 copy(b[0:20], tx.FromEthAddr.Bytes())
160 pkComp := tx.FromBJJ.Compress()
161 copy(b[20:52], pkComp[:])
162 fromIdxBytes, err := tx.FromIdx.Bytes()
163 if err != nil {
164 return nil, err
165 }
166 copy(b[52:58], fromIdxBytes[:])
167 loadAmountFloat16, err := NewFloat16(tx.LoadAmount)
168 if err != nil {
169 return nil, err
170 }
171 copy(b[58:60], loadAmountFloat16.Bytes())
172 amountFloat16, err := NewFloat16(tx.Amount)
173 if err != nil {
174 return nil, err
175 }
176 copy(b[60:62], amountFloat16.Bytes())
177 copy(b[62:66], tx.TokenID.Bytes())
178 toIdxBytes, err := tx.ToIdx.Bytes()
179 if err != nil {
180 return nil, err
181 }
182 copy(b[66:72], toIdxBytes[:])
183 return b[:], nil
184}
185
186// BytesCoordinatorTx encodes a L1CoordinatorTx into []byte
187func (tx *L1Tx) BytesCoordinatorTx(compressedSignatureBytes []byte) ([]byte, error) {
188 var b [L1CoordinatorTxBytesLen]byte
189 v := compressedSignatureBytes[64]
190 s := compressedSignatureBytes[32:64]
191 r := compressedSignatureBytes[0:32]
192 b[0] = v
193 copy(b[1:33], s)
194 copy(b[33:65], r)
195 pkComp := tx.FromBJJ.Compress()
196 copy(b[65:97], pkComp[:])
197 copy(b[97:101], tx.TokenID.Bytes())
198 return b[:], nil
199}
200
201// L1TxFromBytes decodes a L1Tx from []byte
202func L1TxFromBytes(b []byte) (*L1Tx, error) {
203 if len(b) != L1TxBytesLen {
204 return nil, fmt.Errorf("Can not parse L1Tx bytes, expected length %d, current: %d", 68, len(b))
205 }
206
207 tx := &L1Tx{}
208 var err error
209 tx.FromEthAddr = ethCommon.BytesToAddress(b[0:20])
210 pkCompB := b[20:52]
211 var pkComp babyjub.PublicKeyComp
212 copy(pkComp[:], pkCompB)
213 tx.FromBJJ, err = pkComp.Decompress()
214 if err != nil {
215 return nil, err
216 }
217 fromIdx, err := IdxFromBytes(b[52:58])
218 if err != nil {
219 return nil, err
220 }
221 if fromIdx != 0 {
222 tx.FromIdx = new(Idx)
223 *tx.FromIdx = fromIdx
224 }
225 tx.LoadAmount = Float16FromBytes(b[58:60]).BigInt()
226 tx.Amount = Float16FromBytes(b[60:62]).BigInt()
227 tx.TokenID, err = TokenIDFromBytes(b[62:66])
228 if err != nil {
229 return nil, err
230 }
231 tx.ToIdx, err = IdxFromBytes(b[66:72])
232 if err != nil {
233 return nil, err
234 }
235
236 return tx, nil
237}
238
239// L1TxFromCoordinatorBytes decodes a L1Tx from []byte
240func L1TxFromCoordinatorBytes(b []byte) (*L1Tx, error) {
241 if len(b) != L1CoordinatorTxBytesLen {
242 return nil, fmt.Errorf("Can not parse L1CoordinatorTx bytes, expected length %d, current: %d", 101, len(b))
243 }
244
245 bytesMessage1 := []byte("\x19Ethereum Signed Message:\n98")
246 bytesMessage2 := []byte("I authorize this babyjubjub key for hermez rollup account creation")
247
248 tx := &L1Tx{}
249 var err error
250 // Ethereum adds 27 to v
251 v := b[0] - byte(27) //nolint:gomnd
252 s := b[1:33]
253 r := b[33:65]
254
255 pkCompB := b[65:97]
256 var pkComp babyjub.PublicKeyComp
257 copy(pkComp[:], pkCompB)
258 tx.FromBJJ, err = pkComp.Decompress()
259 if err != nil {
260 return nil, err
261 }
262 tx.TokenID, err = TokenIDFromBytes(b[97:101])
263 if err != nil {
264 return nil, err
265 }
266
267 var data []byte
268 data = append(data, bytesMessage1...)
269 data = append(data, bytesMessage2...)
270 data = append(data, pkCompB...)
271 var signature []byte
272 signature = append(signature, r[:]...)
273 signature = append(signature, s[:]...)
274 signature = append(signature, v)
275 hash := crypto.Keccak256(data)
276 pubKeyBytes, err := crypto.Ecrecover(hash, signature)
277 if err != nil {
278 return nil, err
279 }
280 pubKey, err := crypto.UnmarshalPubkey(pubKeyBytes)
281 if err != nil {
282 return nil, err
283 }
284 tx.FromEthAddr = crypto.PubkeyToAddress(*pubKey)
285 return tx, nil
286}