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 ethCrypto "github.com/ethereum/go-ethereum/crypto"
10 "github.com/hermeznetwork/tracerr"
11 "github.com/iden3/go-iden3-crypto/babyjub"
12)
13
14// L1Tx is a struct that represents a L1 tx
15type L1Tx struct {
16 // Stored in DB: mandatory fileds
17
18 // TxID (32 bytes) for L1Tx is the Keccak256 (ethereum) hash of:
19 // bytes: | 1 | 8 | 2 | 1 |
20 // values: | type | ToForgeL1TxsNum | Position | 0 (padding) |
21 // where type:
22 // - L1UserTx: 0
23 // - L1CoordinatorTx: 1
24 TxID TxID `meddler:"id"`
25 // ToForgeL1TxsNum indicates in which the tx was forged / will be forged
26 ToForgeL1TxsNum *int64 `meddler:"to_forge_l1_txs_num"`
27 Position int `meddler:"position"`
28 // UserOrigin is set to true if the tx was originated by a user, false if it was
29 // aoriginated by a coordinator. Note that this differ from the spec for implementation
30 // simplification purpposes
31 UserOrigin bool `meddler:"user_origin"`
32 // FromIdx is used by L1Tx/Deposit to indicate the Idx receiver of the L1Tx.DepositAmount
33 // (deposit)
34 FromIdx Idx `meddler:"from_idx,zeroisnull"`
35 EffectiveFromIdx Idx `meddler:"effective_from_idx,zeroisnull"`
36 FromEthAddr ethCommon.Address `meddler:"from_eth_addr,zeroisnull"`
37 FromBJJ babyjub.PublicKeyComp `meddler:"from_bjj,zeroisnull"`
38 // ToIdx is ignored in L1Tx/Deposit, but used in the L1Tx/DepositAndTransfer
39 ToIdx Idx `meddler:"to_idx"`
40 TokenID TokenID `meddler:"token_id"`
41 Amount *big.Int `meddler:"amount,bigint"`
42 // EffectiveAmount only applies to L1UserTx.
43 EffectiveAmount *big.Int `meddler:"effective_amount,bigintnull"`
44 DepositAmount *big.Int `meddler:"deposit_amount,bigint"`
45 // EffectiveDepositAmount only applies to L1UserTx.
46 EffectiveDepositAmount *big.Int `meddler:"effective_deposit_amount,bigintnull"`
47 // Ethereum Block Number in which this L1Tx was added to the queue
48 EthBlockNum int64 `meddler:"eth_block_num"`
49 Type TxType `meddler:"type"`
50 BatchNum *BatchNum `meddler:"batch_num"`
51}
52
53// NewL1Tx returns the given L1Tx with the TxId & Type parameters calculated
54// from the L1Tx values
55func NewL1Tx(tx *L1Tx) (*L1Tx, error) {
56 txTypeOld := tx.Type
57 if err := tx.SetType(); err != nil {
58 return nil, tracerr.Wrap(err)
59 }
60 // If original Type doesn't match the correct one, return error
61 if txTypeOld != "" && txTypeOld != tx.Type {
62 return nil, tracerr.Wrap(fmt.Errorf("L1Tx.Type: %s, should be: %s",
63 tx.Type, txTypeOld))
64 }
65
66 txIDOld := tx.TxID
67 if err := tx.SetID(); err != nil {
68 return nil, tracerr.Wrap(err)
69 }
70 // If original TxID doesn't match the correct one, return error
71 if txIDOld != (TxID{}) && txIDOld != tx.TxID {
72 return tx, tracerr.Wrap(fmt.Errorf("L1Tx.TxID: %s, should be: %s",
73 tx.TxID.String(), txIDOld.String()))
74 }
75
76 return tx, nil
77}
78
79// SetType sets the type of the transaction
80func (tx *L1Tx) SetType() error {
81 if tx.FromIdx == 0 {
82 if tx.ToIdx == Idx(0) {
83 tx.Type = TxTypeCreateAccountDeposit
84 } else if tx.ToIdx >= IdxUserThreshold {
85 tx.Type = TxTypeCreateAccountDepositTransfer
86 } else {
87 return tracerr.Wrap(fmt.Errorf(
88 "Can not determine type of L1Tx, invalid ToIdx value: %d", tx.ToIdx))
89 }
90 } else if tx.FromIdx >= IdxUserThreshold {
91 if tx.ToIdx == Idx(0) {
92 tx.Type = TxTypeDeposit
93 } else if tx.ToIdx == Idx(1) {
94 tx.Type = TxTypeForceExit
95 } else if tx.ToIdx >= IdxUserThreshold {
96 if tx.DepositAmount.Int64() == int64(0) {
97 tx.Type = TxTypeForceTransfer
98 } else {
99 tx.Type = TxTypeDepositTransfer
100 }
101 } else {
102 return tracerr.Wrap(fmt.Errorf(
103 "Can not determine type of L1Tx, invalid ToIdx value: %d", tx.ToIdx))
104 }
105 } else {
106 return tracerr.Wrap(fmt.Errorf(
107 "Can not determine type of L1Tx, invalid FromIdx value: %d", tx.FromIdx))
108 }
109 return nil
110}
111
112// SetID sets the ID of the transaction. For L1UserTx uses (ToForgeL1TxsNum,
113// Position), for L1CoordinatorTx uses (BatchNum, Position).
114func (tx *L1Tx) SetID() error {
115 var b []byte
116 if tx.UserOrigin {
117 if tx.ToForgeL1TxsNum == nil {
118 return tracerr.Wrap(fmt.Errorf("L1Tx.UserOrigin == true && L1Tx.ToForgeL1TxsNum == nil"))
119 }
120 tx.TxID[0] = TxIDPrefixL1UserTx
121
122 var toForgeL1TxsNumBytes [8]byte
123 binary.BigEndian.PutUint64(toForgeL1TxsNumBytes[:], uint64(*tx.ToForgeL1TxsNum))
124 b = append(b, toForgeL1TxsNumBytes[:]...)
125 } else {
126 if tx.BatchNum == nil {
127 return tracerr.Wrap(fmt.Errorf("L1Tx.UserOrigin == false && L1Tx.BatchNum == nil"))
128 }
129 tx.TxID[0] = TxIDPrefixL1CoordTx
130
131 var batchNumBytes [8]byte
132 binary.BigEndian.PutUint64(batchNumBytes[:], uint64(*tx.BatchNum))
133 b = append(b, batchNumBytes[:]...)
134 }
135 var positionBytes [2]byte
136 binary.BigEndian.PutUint16(positionBytes[:], uint16(tx.Position))
137 b = append(b, positionBytes[:]...)
138
139 // calculate hash
140 h := ethCrypto.Keccak256Hash(b).Bytes()
141
142 copy(tx.TxID[1:], h)
143
144 return nil
145}
146
147// Tx returns a *Tx from the L1Tx
148func (tx L1Tx) Tx() Tx {
149 f := new(big.Float).SetInt(tx.EffectiveAmount)
150 amountFloat, _ := f.Float64()
151 userOrigin := new(bool)
152 *userOrigin = tx.UserOrigin
153 genericTx := Tx{
154 IsL1: true,
155 TxID: tx.TxID,
156 Type: tx.Type,
157 Position: tx.Position,
158 FromIdx: tx.FromIdx,
159 ToIdx: tx.ToIdx,
160 Amount: tx.EffectiveAmount,
161 AmountFloat: amountFloat,
162 TokenID: tx.TokenID,
163 ToForgeL1TxsNum: tx.ToForgeL1TxsNum,
164 UserOrigin: userOrigin,
165 FromEthAddr: tx.FromEthAddr,
166 FromBJJ: tx.FromBJJ,
167 DepositAmount: tx.EffectiveDepositAmount,
168 EthBlockNum: tx.EthBlockNum,
169 }
170 if tx.DepositAmount != nil {
171 lf := new(big.Float).SetInt(tx.DepositAmount)
172 depositAmountFloat, _ := lf.Float64()
173 genericTx.DepositAmountFloat = &depositAmountFloat
174 }
175 return genericTx
176}
177
178// TxCompressedData spec:
179// [ 1 bits ] empty (toBJJSign) // 1 byte
180// [ 8 bits ] empty (userFee) // 1 byte
181// [ 40 bits ] empty (nonce) // 5 bytes
182// [ 32 bits ] tokenID // 4 bytes
183// [ 48 bits ] toIdx // 6 bytes
184// [ 48 bits ] fromIdx // 6 bytes
185// [ 16 bits ] chainId // 2 bytes
186// [ 32 bits ] empty (signatureConstant) // 4 bytes
187// Total bits compressed data: 225 bits // 29 bytes in *big.Int representation
188func (tx L1Tx) TxCompressedData(chainID uint16) (*big.Int, error) {
189 var b [29]byte
190 // b[0:7] empty: no ToBJJSign, no fee, no nonce
191 copy(b[7:11], tx.TokenID.Bytes())
192 toIdxBytes, err := tx.ToIdx.Bytes()
193 if err != nil {
194 return nil, tracerr.Wrap(err)
195 }
196 copy(b[11:17], toIdxBytes[:])
197 fromIdxBytes, err := tx.FromIdx.Bytes()
198 if err != nil {
199 return nil, tracerr.Wrap(err)
200 }
201 copy(b[17:23], fromIdxBytes[:])
202 binary.BigEndian.PutUint16(b[23:25], chainID)
203 copy(b[25:29], SignatureConstantBytes[:])
204
205 bi := new(big.Int).SetBytes(b[:])
206 return bi, nil
207}
208
209// BytesDataAvailability encodes a L1Tx into []byte for the Data Availability
210// [ fromIdx | toIdx | amountFloat40 | Fee ]
211func (tx *L1Tx) BytesDataAvailability(nLevels uint32) ([]byte, error) {
212 idxLen := nLevels / 8 //nolint:gomnd
213
214 b := make([]byte, ((nLevels*2)+40+8)/8) //nolint:gomnd
215
216 fromIdxBytes, err := tx.FromIdx.Bytes()
217 if err != nil {
218 return nil, tracerr.Wrap(err)
219 }
220 copy(b[0:idxLen], fromIdxBytes[6-idxLen:])
221 toIdxBytes, err := tx.ToIdx.Bytes()
222 if err != nil {
223 return nil, tracerr.Wrap(err)
224 }
225 copy(b[idxLen:idxLen*2], toIdxBytes[6-idxLen:])
226
227 if tx.EffectiveAmount != nil {
228 amountFloat40, err := NewFloat40(tx.EffectiveAmount)
229 if err != nil {
230 return nil, tracerr.Wrap(err)
231 }
232 amountFloat40Bytes, err := amountFloat40.Bytes()
233 if err != nil {
234 return nil, tracerr.Wrap(err)
235 }
236 copy(b[idxLen*2:idxLen*2+Float40BytesLength], amountFloat40Bytes)
237 }
238 // fee = 0 (as is L1Tx)
239 return b[:], nil
240}
241
242// L1TxFromDataAvailability decodes a L1Tx from []byte (Data Availability)
243func L1TxFromDataAvailability(b []byte, nLevels uint32) (*L1Tx, error) {
244 idxLen := nLevels / 8 //nolint:gomnd
245
246 fromIdxBytes := b[0:idxLen]
247 toIdxBytes := b[idxLen : idxLen*2]
248 amountBytes := b[idxLen*2 : idxLen*2+Float40BytesLength]
249
250 l1tx := L1Tx{}
251 fromIdx, err := IdxFromBytes(ethCommon.LeftPadBytes(fromIdxBytes, 6))
252 if err != nil {
253 return nil, tracerr.Wrap(err)
254 }
255 l1tx.FromIdx = fromIdx
256 toIdx, err := IdxFromBytes(ethCommon.LeftPadBytes(toIdxBytes, 6))
257 if err != nil {
258 return nil, tracerr.Wrap(err)
259 }
260 l1tx.ToIdx = toIdx
261 l1tx.EffectiveAmount, err = Float40FromBytes(amountBytes).BigInt()
262 return &l1tx, err
263}
264
265// BytesGeneric returns the generic representation of a L1Tx. This method is
266// used to compute the []byte representation of a L1UserTx, and also to compute
267// the L1TxData for the ZKInputs (at the HashGlobalInputs), using this method
268// for L1CoordinatorTxs & L1UserTxs (for the ZKInputs case).
269func (tx *L1Tx) BytesGeneric() ([]byte, error) {
270 var b [RollupConstL1UserTotalBytes]byte
271 copy(b[0:20], tx.FromEthAddr.Bytes())
272 if tx.FromBJJ != EmptyBJJComp {
273 pkCompL := tx.FromBJJ
274 pkCompB := SwapEndianness(pkCompL[:])
275 copy(b[20:52], pkCompB[:])
276 }
277 fromIdxBytes, err := tx.FromIdx.Bytes()
278 if err != nil {
279 return nil, tracerr.Wrap(err)
280 }
281 copy(b[52:58], fromIdxBytes[:])
282
283 depositAmountFloat40, err := NewFloat40(tx.DepositAmount)
284 if err != nil {
285 return nil, tracerr.Wrap(err)
286 }
287 depositAmountFloat40Bytes, err := depositAmountFloat40.Bytes()
288 if err != nil {
289 return nil, tracerr.Wrap(err)
290 }
291 copy(b[58:63], depositAmountFloat40Bytes)
292
293 amountFloat40, err := NewFloat40(tx.Amount)
294 if err != nil {
295 return nil, tracerr.Wrap(err)
296 }
297 amountFloat40Bytes, err := amountFloat40.Bytes()
298 if err != nil {
299 return nil, tracerr.Wrap(err)
300 }
301 copy(b[63:68], amountFloat40Bytes)
302
303 copy(b[68:72], tx.TokenID.Bytes())
304 toIdxBytes, err := tx.ToIdx.Bytes()
305 if err != nil {
306 return nil, tracerr.Wrap(err)
307 }
308 copy(b[72:78], toIdxBytes[:])
309 return b[:], nil
310}
311
312// BytesUser encodes a L1UserTx into []byte
313func (tx *L1Tx) BytesUser() ([]byte, error) {
314 if !tx.UserOrigin {
315 return nil, tracerr.Wrap(fmt.Errorf("Can not calculate BytesUser() for a L1CoordinatorTx"))
316 }
317 return tx.BytesGeneric()
318}
319
320// BytesCoordinatorTx encodes a L1CoordinatorTx into []byte
321func (tx *L1Tx) BytesCoordinatorTx(compressedSignatureBytes []byte) ([]byte, error) {
322 if tx.UserOrigin {
323 return nil, tracerr.Wrap(fmt.Errorf("Can not calculate BytesCoordinatorTx() for a L1UserTx"))
324 }
325 var b [RollupConstL1CoordinatorTotalBytes]byte
326 v := compressedSignatureBytes[64]
327 s := compressedSignatureBytes[32:64]
328 r := compressedSignatureBytes[0:32]
329 b[0] = v
330 copy(b[1:33], s)
331 copy(b[33:65], r)
332 pkCompL := tx.FromBJJ
333 pkCompB := SwapEndianness(pkCompL[:])
334 copy(b[65:97], pkCompB[:])
335 copy(b[97:101], tx.TokenID.Bytes())
336 return b[:], nil
337}
338
339// L1UserTxFromBytes decodes a L1Tx from []byte
340func L1UserTxFromBytes(b []byte) (*L1Tx, error) {
341 if len(b) != RollupConstL1UserTotalBytes {
342 return nil,
343 tracerr.Wrap(fmt.Errorf("Can not parse L1Tx bytes, expected length %d, current: %d",
344 68, len(b)))
345 }
346
347 tx := &L1Tx{
348 UserOrigin: true,
349 }
350 var err error
351 tx.FromEthAddr = ethCommon.BytesToAddress(b[0:20])
352
353 pkCompB := b[20:52]
354 pkCompL := SwapEndianness(pkCompB)
355 copy(tx.FromBJJ[:], pkCompL)
356 fromIdx, err := IdxFromBytes(b[52:58])
357 if err != nil {
358 return nil, tracerr.Wrap(err)
359 }
360 tx.FromIdx = fromIdx
361 tx.DepositAmount, err = Float40FromBytes(b[58:63]).BigInt()
362 if err != nil {
363 return nil, tracerr.Wrap(err)
364 }
365 tx.Amount, err = Float40FromBytes(b[63:68]).BigInt()
366 if err != nil {
367 return nil, tracerr.Wrap(err)
368 }
369 tx.TokenID, err = TokenIDFromBytes(b[68:72])
370 if err != nil {
371 return nil, tracerr.Wrap(err)
372 }
373 tx.ToIdx, err = IdxFromBytes(b[72:78])
374 if err != nil {
375 return nil, tracerr.Wrap(err)
376 }
377
378 return tx, nil
379}
380
381// L1CoordinatorTxFromBytes decodes a L1Tx from []byte
382func L1CoordinatorTxFromBytes(b []byte, chainID *big.Int, hermezAddress ethCommon.Address) (*L1Tx,
383 error) {
384 if len(b) != RollupConstL1CoordinatorTotalBytes {
385 return nil, tracerr.Wrap(
386 fmt.Errorf("Can not parse L1CoordinatorTx bytes, expected length %d, current: %d",
387 101, len(b)))
388 }
389
390 tx := &L1Tx{
391 UserOrigin: false,
392 }
393 var err error
394 v := b[0]
395 s := b[1:33]
396 r := b[33:65]
397 pkCompB := b[65:97]
398 pkCompL := SwapEndianness(pkCompB)
399 copy(tx.FromBJJ[:], pkCompL)
400 tx.TokenID, err = TokenIDFromBytes(b[97:101])
401 if err != nil {
402 return nil, tracerr.Wrap(err)
403 }
404 tx.Amount = big.NewInt(0)
405 tx.DepositAmount = big.NewInt(0)
406 if int(v) > 0 {
407 // L1CoordinatorTX ETH
408 // Ethereum adds 27 to v
409 v = b[0] - byte(27) //nolint:gomnd
410 var signature []byte
411 signature = append(signature, r[:]...)
412 signature = append(signature, s[:]...)
413 signature = append(signature, v)
414
415 accCreationAuth := AccountCreationAuth{
416 BJJ: tx.FromBJJ,
417 }
418 h, err := accCreationAuth.HashToSign(uint16(chainID.Uint64()), hermezAddress)
419 if err != nil {
420 return nil, tracerr.Wrap(err)
421 }
422
423 pubKeyBytes, err := ethCrypto.Ecrecover(h, signature)
424 if err != nil {
425 return nil, tracerr.Wrap(err)
426 }
427 pubKey, err := ethCrypto.UnmarshalPubkey(pubKeyBytes)
428 if err != nil {
429 return nil, tracerr.Wrap(err)
430 }
431 tx.FromEthAddr = ethCrypto.PubkeyToAddress(*pubKey)
432 } else {
433 // L1Coordinator Babyjub
434 tx.FromEthAddr = RollupConstEthAddressInternalOnly
435 }
436 return tx, nil
437}