Update AccountCreationAuth & fix auth.HashToSign

- Fix AccountCreationAuth.HashToSign (was using `[]byte("0x...")`, which
uses the bytes of the string. Now uses the bytearray of the compressed
BJJ public key (compatible with js implementation))
- Update AccountCreationAuth to last specification (add to hash
parameters ChainID & HermezAddress)
- Add missing test to AccountCreationAuth

api/accountcreationauths.go

@@ -21,7 +21,7 @@ func (a *API) postAccountCreationAuth(c *gin.Context) {
 	}
 	// API to common + verify signature
 	commonAuth := accountCreationAuthAPIToCommon(&apiAuth)
-	if !commonAuth.VerifySignature() {
+	if !commonAuth.VerifySignature(a.chainID, a.hermezAddress) {
 		retBadReq(errors.New("invalid signature"), c)
 		return
 	}

api/api.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"sync"
 
+	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/gin-gonic/gin"
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/hermeznetwork/hermez-node/db/historydb"
@@ -31,12 +32,13 @@ type Status struct {
 
 // API serves HTTP requests to allow external interaction with the Hermez node
 type API struct {
-	h       *historydb.HistoryDB
-	cg      *configAPI
-	s       *statedb.StateDB
-	l2      *l2db.L2DB
-	status  Status
-	chainID uint16
+	h             *historydb.HistoryDB
+	cg            *configAPI
+	s             *statedb.StateDB
+	l2            *l2db.L2DB
+	status        Status
+	chainID       uint16
+	hermezAddress ethCommon.Address
 }
 
 // NewAPI sets the endpoints and the appropriate handlers, but doesn't start the server
@@ -47,7 +49,6 @@ func NewAPI(
 	sdb *statedb.StateDB,
 	l2db *l2db.L2DB,
 	config *Config,
-	chainID uint16,
 ) (*API, error) {
 	// Check input
 	// TODO: is stateDB only needed for explorer endpoints or for both?
@@ -65,10 +66,11 @@ func NewAPI(
 			AuctionConstants:  config.AuctionConstants,
 			WDelayerConstants: config.WDelayerConstants,
 		},
-		s:       sdb,
-		l2:      l2db,
-		status:  Status{},
-		chainID: chainID,
+		s:             sdb,
+		l2:            l2db,
+		status:        Status{},
+		chainID:       config.ChainID,
+		hermezAddress: config.HermezAddress,
 	}
 
 	// Add coordinator endpoints

api/api_test.go

@@ -221,7 +221,7 @@ func TestMain(m *testing.M) {
 	test.WipeDB(l2DB.DB()) // this will clean HistoryDB and L2DB
 
 	// Config (smart contract constants)
-	_config := getConfigTest()
+	_config := getConfigTest(chainID)
 	config = configAPI{
 		RollupConstants:   *newRollupConstants(_config.RollupConstants),
 		AuctionConstants:  _config.AuctionConstants,
@@ -238,7 +238,6 @@ func TestMain(m *testing.M) {
 		sdb,
 		l2DB,
 		&_config,
-		chainID,
 	)
 	if err != nil {
 		panic(err)
@@ -423,7 +422,7 @@ func TestMain(m *testing.M) {
 		exits:            testExits,
 		poolTxsToSend:    poolTxsToSend,
 		poolTxsToReceive: poolTxsToReceive,
-		auths:            genTestAuths(test.GenAuths(5)),
+		auths:            genTestAuths(test.GenAuths(5, _config.ChainID, _config.HermezAddress)),
 		router:           router,
 		bids:             testBids,
 		slots: api.genTestSlots(

api/config.go

@@ -4,6 +4,7 @@ import (
 	"math/big"
 	"net/http"
 
+	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/gin-gonic/gin"
 	"github.com/hermeznetwork/hermez-node/common"
 )
@@ -51,6 +52,8 @@ type Config struct {
 	RollupConstants   common.RollupConstants
 	AuctionConstants  common.AuctionConstants
 	WDelayerConstants common.WDelayerConstants
+	ChainID           uint16
+	HermezAddress     ethCommon.Address
 }
 
 type configAPI struct {

api/config_test.go

@@ -9,7 +9,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func getConfigTest() Config {
+func getConfigTest(chainID uint16) Config {
 	var config Config
 
 	var rollupPublicConstants common.RollupConstants
@@ -40,6 +40,9 @@ func getConfigTest() Config {
 	config.AuctionConstants = auctionConstants
 	config.WDelayerConstants = wdelayerConstants
 
+	config.ChainID = chainID
+	config.HermezAddress = ethCommon.HexToAddress("0xc344E203a046Da13b0B4467EB7B3629D0C99F6E6")
+
 	return config
 }