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package api
import (
"encoding/base64"
"encoding/hex"
"errors"
"fmt"
"math/big"
"strconv"
"strings"
"time"
ethCommon "github.com/ethereum/go-ethereum/common"
"github.com/hermeznetwork/hermez-node/common"
"github.com/hermeznetwork/hermez-node/db"
"github.com/hermeznetwork/hermez-node/db/historydb"
"github.com/hermeznetwork/hermez-node/db/l2db"
"github.com/hermeznetwork/hermez-node/eth"
"github.com/iden3/go-iden3-crypto/babyjub"
)
const exitIdx = "hez:EXIT:1"
type errorMsg struct {
Message string
}
func bjjToString(bjj *babyjub.PublicKey) string {
pkComp := [32]byte(bjj.Compress())
sum := pkComp[0]
for i := 1; i < len(pkComp); i++ {
sum += pkComp[i]
}
bjjSum := append(pkComp[:], sum)
return "hez:" + base64.RawURLEncoding.EncodeToString(bjjSum)
}
func ethAddrToHez(addr ethCommon.Address) string {
return "hez:" + addr.String()
}
func idxToHez(idx common.Idx, tokenSymbol string) string {
if idx == 1 {
return exitIdx
}
return "hez:" + tokenSymbol + ":" + strconv.Itoa(int(idx))
}
// History Tx
type historyTxsAPI struct {
Txs []historyTxAPI `json:"transactions"`
Pagination *db.Pagination `json:"pagination"`
}
func (htx *historyTxsAPI) GetPagination() *db.Pagination {
if htx.Txs[0].ItemID < htx.Txs[len(htx.Txs)-1].ItemID {
htx.Pagination.FirstReturnedItem = htx.Txs[0].ItemID
htx.Pagination.LastReturnedItem = htx.Txs[len(htx.Txs)-1].ItemID
} else {
htx.Pagination.LastReturnedItem = htx.Txs[0].ItemID
htx.Pagination.FirstReturnedItem = htx.Txs[len(htx.Txs)-1].ItemID
}
return htx.Pagination
}
func (htx *historyTxsAPI) Len() int { return len(htx.Txs) }
type l1Info struct {
ToForgeL1TxsNum *int64 `json:"toForgeL1TransactionsNum"`
UserOrigin bool `json:"userOrigin"`
FromEthAddr string `json:"fromHezEthereumAddress"`
FromBJJ string `json:"fromBJJ"`
LoadAmount string `json:"loadAmount"`
HistoricLoadAmountUSD *float64 `json:"historicLoadAmountUSD"`
EthBlockNum int64 `json:"ethereumBlockNum"`
}
type l2Info struct {
Fee common.FeeSelector `json:"fee"`
HistoricFeeUSD *float64 `json:"historicFeeUSD"`
Nonce common.Nonce `json:"nonce"`
}
type historyTxAPI struct {
IsL1 string `json:"L1orL2"`
TxID common.TxID `json:"id"`
ItemID int `json:"itemId"`
Type common.TxType `json:"type"`
Position int `json:"position"`
FromIdx *string `json:"fromAccountIndex"`
ToIdx string `json:"toAccountIndex"`
Amount string `json:"amount"`
BatchNum *common.BatchNum `json:"batchNum"`
HistoricUSD *float64 `json:"historicUSD"`
Timestamp time.Time `json:"timestamp"`
L1Info *l1Info `json:"L1Info"`
L2Info *l2Info `json:"L2Info"`
Token historydb.TokenWithUSD `json:"token"`
}
func historyTxsToAPI(dbTxs []historydb.HistoryTx) []historyTxAPI {
apiTxs := []historyTxAPI{}
for i := 0; i < len(dbTxs); i++ {
apiTx := historyTxAPI{
TxID: dbTxs[i].TxID,
ItemID: dbTxs[i].ItemID,
Type: dbTxs[i].Type,
Position: dbTxs[i].Position,
ToIdx: idxToHez(dbTxs[i].ToIdx, dbTxs[i].TokenSymbol),
Amount: dbTxs[i].Amount.String(),
HistoricUSD: dbTxs[i].HistoricUSD,
BatchNum: dbTxs[i].BatchNum,
Timestamp: dbTxs[i].Timestamp,
Token: historydb.TokenWithUSD{
TokenID: dbTxs[i].TokenID,
EthBlockNum: dbTxs[i].TokenEthBlockNum,
EthAddr: dbTxs[i].TokenEthAddr,
Name: dbTxs[i].TokenName,
Symbol: dbTxs[i].TokenSymbol,
Decimals: dbTxs[i].TokenDecimals,
USD: dbTxs[i].TokenUSD,
USDUpdate: dbTxs[i].TokenUSDUpdate,
},
L1Info: nil,
L2Info: nil,
}
if dbTxs[i].FromIdx != nil {
fromIdx := new(string)
*fromIdx = idxToHez(*dbTxs[i].FromIdx, dbTxs[i].TokenSymbol)
apiTx.FromIdx = fromIdx
}
if dbTxs[i].IsL1 {
apiTx.IsL1 = "L1"
apiTx.L1Info = &l1Info{
ToForgeL1TxsNum: dbTxs[i].ToForgeL1TxsNum,
UserOrigin: *dbTxs[i].UserOrigin,
FromEthAddr: ethAddrToHez(*dbTxs[i].FromEthAddr),
FromBJJ: bjjToString(dbTxs[i].FromBJJ),
LoadAmount: dbTxs[i].LoadAmount.String(),
HistoricLoadAmountUSD: dbTxs[i].HistoricLoadAmountUSD,
EthBlockNum: dbTxs[i].EthBlockNum,
}
} else {
apiTx.IsL1 = "L2"
apiTx.L2Info = &l2Info{
Fee: *dbTxs[i].Fee,
HistoricFeeUSD: dbTxs[i].HistoricFeeUSD,
Nonce: *dbTxs[i].Nonce,
}
}
apiTxs = append(apiTxs, apiTx)
}
return apiTxs
}
// Exit
type exitsAPI struct {
Exits []exitAPI `json:"exits"`
Pagination *db.Pagination `json:"pagination"`
}
func (e *exitsAPI) GetPagination() *db.Pagination {
if e.Exits[0].ItemID < e.Exits[len(e.Exits)-1].ItemID {
e.Pagination.FirstReturnedItem = e.Exits[0].ItemID
e.Pagination.LastReturnedItem = e.Exits[len(e.Exits)-1].ItemID
} else {
e.Pagination.LastReturnedItem = e.Exits[0].ItemID
e.Pagination.FirstReturnedItem = e.Exits[len(e.Exits)-1].ItemID
}
return e.Pagination
}
func (e *exitsAPI) Len() int { return len(e.Exits) }
type merkleProofAPI struct {
Root string
Siblings []string
OldKey string
OldValue string
IsOld0 bool
Key string
Value string
Fnc int
}
type exitAPI struct {
ItemID int `json:"itemId"`
BatchNum common.BatchNum `json:"batchNum"`
AccountIdx string `json:"accountIndex"`
MerkleProof merkleProofAPI `json:"merkleProof"`
Balance string `json:"balance"`
InstantWithdrawn *int64 `json:"instantWithdrawn"`
DelayedWithdrawRequest *int64 `json:"delayedWithdrawRequest"`
DelayedWithdrawn *int64 `json:"delayedWithdrawn"`
Token historydb.TokenWithUSD `json:"token"`
}
func historyExitsToAPI(dbExits []historydb.HistoryExit) []exitAPI {
apiExits := []exitAPI{}
for i := 0; i < len(dbExits); i++ {
exit := exitAPI{
ItemID: dbExits[i].ItemID,
BatchNum: dbExits[i].BatchNum,
AccountIdx: idxToHez(dbExits[i].AccountIdx, dbExits[i].TokenSymbol),
MerkleProof: merkleProofAPI{
Root: dbExits[i].MerkleProof.Root.String(),
OldKey: dbExits[i].MerkleProof.OldKey.String(),
OldValue: dbExits[i].MerkleProof.OldValue.String(),
IsOld0: dbExits[i].MerkleProof.IsOld0,
Key: dbExits[i].MerkleProof.Key.String(),
Value: dbExits[i].MerkleProof.Value.String(),
Fnc: dbExits[i].MerkleProof.Fnc,
},
Balance: dbExits[i].Balance.String(),
InstantWithdrawn: dbExits[i].InstantWithdrawn,
DelayedWithdrawRequest: dbExits[i].DelayedWithdrawRequest,
DelayedWithdrawn: dbExits[i].DelayedWithdrawn,
Token: historydb.TokenWithUSD{
TokenID: dbExits[i].TokenID,
EthBlockNum: dbExits[i].TokenEthBlockNum,
EthAddr: dbExits[i].TokenEthAddr,
Name: dbExits[i].TokenName,
Symbol: dbExits[i].TokenSymbol,
Decimals: dbExits[i].TokenDecimals,
USD: dbExits[i].TokenUSD,
USDUpdate: dbExits[i].TokenUSDUpdate,
},
}
siblings := []string{}
for j := 0; j < len(dbExits[i].MerkleProof.Siblings); j++ {
siblings = append(siblings, dbExits[i].MerkleProof.Siblings[j].String())
}
exit.MerkleProof.Siblings = siblings
apiExits = append(apiExits, exit)
}
return apiExits
}
// Config
type rollupConstants struct {
PublicConstants eth.RollupPublicConstants `json:"publicConstants"`
MaxFeeIdxCoordinator int `json:"maxFeeIdxCoordinator"`
ReservedIdx int `json:"reservedIdx"`
ExitIdx int `json:"exitIdx"`
LimitLoadAmount *big.Int `json:"limitLoadAmount"`
LimitL2TransferAmount *big.Int `json:"limitL2TransferAmount"`
LimitTokens int `json:"limitTokens"`
L1CoordinatorTotalBytes int `json:"l1CoordinatorTotalBytes"`
L1UserTotalBytes int `json:"l1UserTotalBytes"`
MaxL1UserTx int `json:"maxL1UserTx"`
MaxL1Tx int `json:"maxL1Tx"`
InputSHAConstantBytes int `json:"inputSHAConstantBytes"`
NumBuckets int `json:"numBuckets"`
MaxWithdrawalDelay int `json:"maxWithdrawalDelay"`
ExchangeMultiplier int `json:"exchangeMultiplier"`
}
type configAPI struct {
RollupConstants rollupConstants `json:"hermez"`
AuctionConstants eth.AuctionConstants `json:"auction"`
WDelayerConstants eth.WDelayerConstants `json:"withdrawalDelayer"`
}
// PoolL2Tx
type receivedPoolTx struct {
TxID common.TxID `json:"id" binding:"required"`
Type common.TxType `json:"type" binding:"required"`
TokenID common.TokenID `json:"tokenId"`
FromIdx string `json:"fromAccountIndex" binding:"required"`
ToIdx *string `json:"toAccountIndex"`
ToEthAddr *string `json:"toHezEthereumAddress"`
ToBJJ *string `json:"toBjj"`
Amount string `json:"amount" binding:"required"`
Fee common.FeeSelector `json:"fee"`
Nonce common.Nonce `json:"nonce"`
Signature babyjub.SignatureComp `json:"signature" binding:"required"`
RqFromIdx *string `json:"requestFromAccountIndex"`
RqToIdx *string `json:"requestToAccountIndex"`
RqToEthAddr *string `json:"requestToHezEthereumAddress"`
RqToBJJ *string `json:"requestToBjj"`
RqTokenID *common.TokenID `json:"requestTokenId"`
RqAmount *string `json:"requestAmount"`
RqFee *common.FeeSelector `json:"requestFee"`
RqNonce *common.Nonce `json:"requestNonce"`
}
func (tx *receivedPoolTx) toDBWritePoolL2Tx() (*l2db.PoolL2TxWrite, error) {
amount := new(big.Int)
amount.SetString(tx.Amount, 10)
txw := &l2db.PoolL2TxWrite{
TxID: tx.TxID,
TokenID: tx.TokenID,
Amount: amount,
Fee: tx.Fee,
Nonce: tx.Nonce,
State: common.PoolL2TxStatePending,
Signature: tx.Signature,
RqTokenID: tx.RqTokenID,
RqFee: tx.RqFee,
RqNonce: tx.RqNonce,
Type: tx.Type,
}
// Check FromIdx (required)
fidx, err := stringToIdx(tx.FromIdx, "fromAccountIndex")
if err != nil {
return nil, err
}
if fidx == nil {
return nil, errors.New("invalid fromAccountIndex")
}
// Set FromIdx
txw.FromIdx = common.Idx(*fidx)
// Set AmountFloat
f := new(big.Float).SetInt(amount)
amountF, _ := f.Float64()
txw.AmountFloat = amountF
if amountF < 0 {
return nil, errors.New("amount must be positive")
}
// Check "to" fields, only one of: ToIdx, ToEthAddr, ToBJJ
if tx.ToIdx != nil { // Case: Tx with ToIdx setted
// Set ToIdx
tidxUint, err := stringToIdx(*tx.ToIdx, "toAccountIndex")
if err != nil || tidxUint == nil {
return nil, errors.New("invalid toAccountIndex")
}
tidx := common.Idx(*tidxUint)
txw.ToIdx = &tidx
} else if tx.ToBJJ != nil { // Case: Tx with ToBJJ setted
// tx.ToEthAddr must be equal to ethAddrWhenBJJLower or ethAddrWhenBJJUpper
if tx.ToEthAddr != nil {
toEthAddr, err := hezStringToEthAddr(*tx.ToEthAddr, "toHezEthereumAddress")
if err != nil || *toEthAddr != common.FFAddr {
return nil, fmt.Errorf("if toBjj is setted, toHezEthereumAddress must be hez:%s", common.FFAddr.Hex())
}
} else {
return nil, fmt.Errorf("if toBjj is setted, toHezEthereumAddress must be hez:%s and toAccountIndex must be null", common.FFAddr.Hex())
}
// Set ToEthAddr and ToBJJ
toBJJ, err := hezStringToBJJ(*tx.ToBJJ, "toBjj")
if err != nil || toBJJ == nil {
return nil, errors.New("invalid toBjj")
}
txw.ToBJJ = toBJJ
txw.ToEthAddr = &common.FFAddr
} else if tx.ToEthAddr != nil { // Case: Tx with ToEthAddr setted
// Set ToEthAddr
toEthAddr, err := hezStringToEthAddr(*tx.ToEthAddr, "toHezEthereumAddress")
if err != nil || toEthAddr == nil {
return nil, errors.New("invalid toHezEthereumAddress")
}
txw.ToEthAddr = toEthAddr
} else {
return nil, errors.New("one of toAccountIndex, toHezEthereumAddress or toBjj must be setted")
}
// Check "rq" fields
if tx.RqFromIdx != nil {
// check and set RqFromIdx
rqfidxUint, err := stringToIdx(tx.FromIdx, "requestFromAccountIndex")
if err != nil || rqfidxUint == nil {
return nil, errors.New("invalid requestFromAccountIndex")
}
// Set RqFromIdx
rqfidx := common.Idx(*rqfidxUint)
txw.RqFromIdx = &rqfidx
// Case: RqTx with RqToIdx setted
if tx.RqToIdx != nil {
// Set ToIdx
tidxUint, err := stringToIdx(*tx.RqToIdx, "requestToAccountIndex")
if err != nil || tidxUint == nil {
return nil, errors.New("invalid requestToAccountIndex")
}
tidx := common.Idx(*tidxUint)
txw.ToIdx = &tidx
} else if tx.RqToBJJ != nil { // Case: Tx with ToBJJ setted
// tx.ToEthAddr must be equal to ethAddrWhenBJJLower or ethAddrWhenBJJUpper
if tx.RqToEthAddr != nil {
rqEthAddr, err := hezStringToEthAddr(*tx.RqToEthAddr, "")
if err != nil || *rqEthAddr != common.FFAddr {
return nil, fmt.Errorf("if requestToBjj is setted, requestToHezEthereumAddress must be hez:%s", common.FFAddr.Hex())
}
} else {
return nil, fmt.Errorf("if requestToBjj is setted, toHezEthereumAddress must be hez:%s and requestToAccountIndex must be null", common.FFAddr.Hex())
}
// Set ToEthAddr and ToBJJ
rqToBJJ, err := hezStringToBJJ(*tx.RqToBJJ, "requestToBjj")
if err != nil || rqToBJJ == nil {
return nil, errors.New("invalid requestToBjj")
}
txw.RqToBJJ = rqToBJJ
txw.RqToEthAddr = &common.FFAddr
} else if tx.RqToEthAddr != nil { // Case: Tx with ToEthAddr setted
// Set ToEthAddr
rqToEthAddr, err := hezStringToEthAddr(*tx.ToEthAddr, "requestToHezEthereumAddress")
if err != nil || rqToEthAddr == nil {
return nil, errors.New("invalid requestToHezEthereumAddress")
}
txw.RqToEthAddr = rqToEthAddr
} else {
return nil, errors.New("one of requestToAccountIndex, requestToHezEthereumAddress or requestToBjj must be setted")
}
if tx.RqAmount == nil {
return nil, errors.New("requestAmount must be provided if other request fields are setted")
}
rqAmount := new(big.Int)
rqAmount.SetString(*tx.RqAmount, 10)
txw.RqAmount = rqAmount
} else if tx.RqToIdx != nil && tx.RqToEthAddr != nil && tx.RqToBJJ != nil &&
tx.RqTokenID != nil && tx.RqAmount != nil && tx.RqNonce != nil && tx.RqFee != nil {
// if tx.RqToIdx is not setted, tx.Rq* must be null as well
return nil, errors.New("if requestFromAccountIndex is setted, the rest of request fields must be null as well")
}
return txw, validatePoolL2TxWrite(txw)
}
func validatePoolL2TxWrite(txw *l2db.PoolL2TxWrite) error {
poolTx := common.PoolL2Tx{
TxID: txw.TxID,
FromIdx: txw.FromIdx,
ToBJJ: txw.ToBJJ,
TokenID: txw.TokenID,
Amount: txw.Amount,
Fee: txw.Fee,
Nonce: txw.Nonce,
State: txw.State,
Signature: txw.Signature,
RqToBJJ: txw.RqToBJJ,
RqAmount: txw.RqAmount,
Type: txw.Type,
}
// ToIdx
if txw.ToIdx != nil {
poolTx.ToIdx = *txw.ToIdx
}
// ToEthAddr
if txw.ToEthAddr == nil {
poolTx.ToEthAddr = common.EmptyAddr
} else {
poolTx.ToEthAddr = *txw.ToEthAddr
}
// RqFromIdx
if txw.RqFromIdx != nil {
poolTx.RqFromIdx = *txw.RqFromIdx
}
// RqToIdx
if txw.RqToIdx != nil {
poolTx.RqToIdx = *txw.RqToIdx
}
// RqToEthAddr
if txw.RqToEthAddr == nil {
poolTx.RqToEthAddr = common.EmptyAddr
} else {
poolTx.RqToEthAddr = *txw.RqToEthAddr
}
// RqTokenID
if txw.RqTokenID != nil {
poolTx.RqTokenID = *txw.RqTokenID
}
// RqFee
if txw.RqFee != nil {
poolTx.RqFee = *txw.RqFee
}
// RqNonce
if txw.RqNonce != nil {
poolTx.RqNonce = *txw.RqNonce
}
// Check type and id
_, err := common.NewPoolL2Tx(&poolTx)
if err != nil {
return err
}
// Check signature
// Get public key
account, err := s.GetAccount(poolTx.FromIdx)
if err != nil {
return err
}
if !poolTx.VerifySignature(account.PublicKey) {
return errors.New("wrong signature")
}
return nil
}
type sendPoolTx struct {
TxID common.TxID `json:"id"`
Type common.TxType `json:"type"`
FromIdx string `json:"fromAccountIndex"`
ToIdx *string `json:"toAccountIndex"`
ToEthAddr *string `json:"toHezEthereumAddress"`
ToBJJ *string `json:"toBjj"`
Amount string `json:"amount"`
Fee common.FeeSelector `json:"fee"`
Nonce common.Nonce `json:"nonce"`
State common.PoolL2TxState `json:"state"`
Signature babyjub.SignatureComp `json:"signature"`
Timestamp time.Time `json:"timestamp"`
BatchNum *common.BatchNum `json:"batchNum"`
RqFromIdx *string `json:"requestFromAccountIndex"`
RqToIdx *string `json:"requestToAccountIndex"`
RqToEthAddr *string `json:"requestToHezEthereumAddress"`
RqToBJJ *string `json:"requestToBJJ"`
RqTokenID *common.TokenID `json:"requestTokenId"`
RqAmount *string `json:"requestAmount"`
RqFee *common.FeeSelector `json:"requestFee"`
RqNonce *common.Nonce `json:"requestNonce"`
Token historydb.TokenWithUSD `json:"token"`
}
func poolL2TxReadToSend(dbTx *l2db.PoolL2TxRead) *sendPoolTx {
tx := &sendPoolTx{
TxID: dbTx.TxID,
Type: dbTx.Type,
FromIdx: idxToHez(dbTx.FromIdx, dbTx.TokenSymbol),
Amount: dbTx.Amount.String(),
Fee: dbTx.Fee,
Nonce: dbTx.Nonce,
State: dbTx.State,
Signature: dbTx.Signature,
Timestamp: dbTx.Timestamp,
BatchNum: dbTx.BatchNum,
RqTokenID: dbTx.RqTokenID,
RqFee: dbTx.RqFee,
RqNonce: dbTx.RqNonce,
Token: historydb.TokenWithUSD{
TokenID: dbTx.TokenID,
EthBlockNum: dbTx.TokenEthBlockNum,
EthAddr: dbTx.TokenEthAddr,
Name: dbTx.TokenName,
Symbol: dbTx.TokenSymbol,
Decimals: dbTx.TokenDecimals,
USD: dbTx.TokenUSD,
USDUpdate: dbTx.TokenUSDUpdate,
},
}
// ToIdx
if dbTx.ToIdx != nil {
toIdx := idxToHez(*dbTx.ToIdx, dbTx.TokenSymbol)
tx.ToIdx = &toIdx
}
// ToEthAddr
if dbTx.ToEthAddr != nil {
toEth := ethAddrToHez(*dbTx.ToEthAddr)
tx.ToEthAddr = &toEth
}
// ToBJJ
if dbTx.ToBJJ != nil {
toBJJ := bjjToString(dbTx.ToBJJ)
tx.ToBJJ = &toBJJ
}
// RqFromIdx
if dbTx.RqFromIdx != nil {
rqFromIdx := idxToHez(*dbTx.RqFromIdx, dbTx.TokenSymbol)
tx.RqFromIdx = &rqFromIdx
}
// RqToIdx
if dbTx.RqToIdx != nil {
rqToIdx := idxToHez(*dbTx.RqToIdx, dbTx.TokenSymbol)
tx.RqToIdx = &rqToIdx
}
// RqToEthAddr
if dbTx.RqToEthAddr != nil {
rqToEth := ethAddrToHez(*dbTx.RqToEthAddr)
tx.RqToEthAddr = &rqToEth
}
// RqToBJJ
if dbTx.RqToBJJ != nil {
rqToBJJ := bjjToString(dbTx.RqToBJJ)
tx.RqToBJJ = &rqToBJJ
}
// RqAmount
if dbTx.RqAmount != nil {
rqAmount := dbTx.RqAmount.String()
tx.RqAmount = &rqAmount
}
return tx
}
// AccountCreationAuth
type accountCreationAuthAPI struct {
EthAddr string `json:"hezEthereumAddress" binding:"required"`
BJJ string `json:"bjj" binding:"required"`
Signature string `json:"signature" binding:"required"`
Timestamp time.Time `json:"timestamp"`
}
func accountCreationAuthToAPI(dbAuth *common.AccountCreationAuth) *accountCreationAuthAPI {
return &accountCreationAuthAPI{
EthAddr: ethAddrToHez(dbAuth.EthAddr),
BJJ: bjjToString(dbAuth.BJJ),
Signature: "0x" + hex.EncodeToString(dbAuth.Signature),
Timestamp: dbAuth.Timestamp,
}
}
func accountCreationAuthAPIToCommon(apiAuth *accountCreationAuthAPI) (*common.AccountCreationAuth, error) {
ethAddr, err := hezStringToEthAddr(apiAuth.EthAddr, "hezEthereumAddress")
if err != nil {
return nil, err
}
bjj, err := hezStringToBJJ(apiAuth.BJJ, "bjj")
if err != nil {
return nil, err
}
without0x := strings.TrimPrefix(apiAuth.Signature, "0x")
s, err := hex.DecodeString(without0x)
if err != nil {
return nil, err
}
auth := &common.AccountCreationAuth{
EthAddr: *ethAddr,
BJJ: bjj,
Signature: s,
Timestamp: apiAuth.Timestamp,
}
if !auth.VerifySignature() {
return nil, errors.New("invalid signature")
}
return auth, nil
}