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

test/l2db.go

@@ -1,6 +1,7 @@
 package test
 
 import (
+	ethCommon "github.com/ethereum/go-ethereum/common"
 	ethCrypto "github.com/ethereum/go-ethereum/crypto"
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/iden3/go-iden3-crypto/babyjub"
@@ -66,7 +67,7 @@ func GenPoolTxs(n int, tokens []common.Token) []*common.PoolL2Tx {
 }
 
 // GenAuths generates account creation authorizations
-func GenAuths(nAuths int) []*common.AccountCreationAuth {
+func GenAuths(nAuths int, chainID uint16, hermezContractAddr ethCommon.Address) []*common.AccountCreationAuth {
 	auths := []*common.AccountCreationAuth{}
 	for i := 0; i < nAuths; i++ {
 		// Generate keys
@@ -81,7 +82,7 @@ func GenAuths(nAuths int) []*common.AccountCreationAuth {
 			BJJ:     bjjPrivK.Public().Compress(),
 		}
 		// Sign
-		h, err := auth.HashToSign()
+		h, err := auth.HashToSign(chainID, hermezContractAddr)
 		if err != nil {
 			panic(err)
 		}

test/l2db_test.go

@@ -3,13 +3,17 @@ package test
 import (
 	"testing"
 
+	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestGenAuths(t *testing.T) {
+	chainID := uint16(0)
+	hermezContractAddr := ethCommon.HexToAddress("0xc344E203a046Da13b0B4467EB7B3629D0C99F6E6")
+
 	const nAuths = 5
-	auths := GenAuths(nAuths)
+	auths := GenAuths(nAuths, chainID, hermezContractAddr)
 	for _, auth := range auths {
-		assert.True(t, auth.VerifySignature())
+		assert.True(t, auth.VerifySignature(chainID, hermezContractAddr))
 	}
 }