Merge pull request #219 from hermeznetwork/feature/api-account-creation

Impl account creation auth endpoints

api/api.go

@@ -11,7 +11,6 @@ import (
 
 var h *historydb.HistoryDB
 var cg *configAPI
-
 var s *statedb.StateDB
 var l2 *l2db.L2DB
 

api/api_test.go

@@ -51,6 +51,7 @@ type testCommon struct {
 	usrExits         []exitAPI
 	poolTxsToSend    []receivedPoolTx
 	poolTxsToReceive []sendPoolTx
+	auths            []accountCreationAuthAPI
 	router           *swagger.Router
 }
 
@@ -637,6 +638,15 @@ func TestMain(m *testing.M) {
 	if err != nil {
 		panic(err)
 	}
+	// Account creation auth
+	const nAuths = 5
+	auths := test.GenAuths(nAuths)
+	// Transform auths to API format
+	apiAuths := []accountCreationAuthAPI{}
+	for _, auth := range auths {
+		apiAuth := accountCreationAuthToAPI(auth)
+		apiAuths = append(apiAuths, *apiAuth)
+	}
 	// Set testCommon
 	tc = testCommon{
 		blocks:           blocks,
@@ -652,6 +662,7 @@ func TestMain(m *testing.M) {
 		usrExits:         usrExits,
 		poolTxsToSend:    poolTxsToSend,
 		poolTxsToReceive: poolTxsToReceive,
+		auths:            apiAuths,
 		router:           router,
 	}
 	// Fake server
@@ -1325,6 +1336,69 @@ func TestGetCoordinators(t *testing.T) {
 	err = doBadReq("GET", path, nil, 404)
 	assert.NoError(t, err)
 }
+func TestAccountCreationAuth(t *testing.T) {
+	// POST
+	endpoint := apiURL + "account-creation-authorization"
+	for _, auth := range tc.auths {
+		jsonAuthBytes, err := json.Marshal(auth)
+		assert.NoError(t, err)
+		jsonAuthReader := bytes.NewReader(jsonAuthBytes)
+		fmt.Println(string(jsonAuthBytes))
+		assert.NoError(
+			t, doGoodReq(
+				"POST",
+				endpoint,
+				jsonAuthReader, nil,
+			),
+		)
+	}
+	// GET
+	endpoint += "/"
+	for _, auth := range tc.auths {
+		fetchedAuth := accountCreationAuthAPI{}
+		assert.NoError(
+			t, doGoodReq(
+				"GET",
+				endpoint+auth.EthAddr,
+				nil, &fetchedAuth,
+			),
+		)
+		assertAuth(t, auth, fetchedAuth)
+	}
+	// POST
+	// 400
+	// Wrong addr
+	badAuth := tc.auths[0]
+	badAuth.EthAddr = ethAddrToHez(ethCommon.BigToAddress(big.NewInt(1)))
+	jsonAuthBytes, err := json.Marshal(badAuth)
+	assert.NoError(t, err)
+	jsonAuthReader := bytes.NewReader(jsonAuthBytes)
+	err = doBadReq("POST", endpoint, jsonAuthReader, 400)
+	assert.NoError(t, err)
+	// Wrong signature
+	badAuth = tc.auths[0]
+	badAuth.Signature = badAuth.Signature[:len(badAuth.Signature)-1]
+	badAuth.Signature += "F"
+	jsonAuthBytes, err = json.Marshal(badAuth)
+	assert.NoError(t, err)
+	jsonAuthReader = bytes.NewReader(jsonAuthBytes)
+	err = doBadReq("POST", endpoint, jsonAuthReader, 400)
+	assert.NoError(t, err)
+	// GET
+	// 400
+	err = doBadReq("GET", endpoint+"hez:0xFooBar", nil, 400)
+	assert.NoError(t, err)
+	// 404
+	err = doBadReq("GET", endpoint+"hez:0x0000000000000000000000000000000000000001", nil, 404)
+	assert.NoError(t, err)
+}
+
+func assertAuth(t *testing.T, expected, actual accountCreationAuthAPI) {
+	// timestamp should be very close to now
+	assert.Less(t, time.Now().UTC().Unix()-3, actual.Timestamp.Unix())
+	expected.Timestamp = actual.Timestamp
+	assert.Equal(t, expected, actual)
+}
 
 func doGoodReqPaginated(
 	path, order string,
@@ -1393,7 +1467,7 @@ func doGoodReq(method, path string, reqBody io.Reader, returnStruct interface{})
 	if err != nil {
 		return err
 	}
-	if resp.Body == nil {
+	if resp.Body == nil && returnStruct != nil {
 		return errors.New("Nil body")
 	}
 	//nolint
@@ -1403,10 +1477,14 @@ func doGoodReq(method, path string, reqBody io.Reader, returnStruct interface{})
 		return err
 	}
 	if resp.StatusCode != 200 {
-		return fmt.Errorf("%d response: %s", resp.StatusCode, string(body))
+		return fmt.Errorf("%d response. Body: %s", resp.StatusCode, string(body))
+	}
+	if returnStruct == nil {
+		return nil
 	}
 	// Unmarshal body into return struct
 	if err := json.Unmarshal(body, returnStruct); err != nil {
+		log.Error("invalid json: " + string(body))
 		return err
 	}
 	// Validate response against swagger spec

api/dbtoapistructs.go

@@ -2,10 +2,12 @@ package api
 
 import (
 	"encoding/base64"
+	"encoding/hex"
 	"errors"
 	"fmt"
 	"math/big"
 	"strconv"
+	"strings"
 	"time"
 
 	ethCommon "github.com/ethereum/go-ethereum/common"
@@ -665,3 +667,47 @@ func coordinatorsToAPI(dbCoordinators []historydb.HistoryCoordinator) []coordina
 	}
 	return apiCoordinators
 }
+
+// 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
+}

api/handlers.go

@@ -30,10 +30,43 @@ var (
 )
 
 func postAccountCreationAuth(c *gin.Context) {
-
+	// Parse body
+	var apiAuth accountCreationAuthAPI
+	if err := c.ShouldBindJSON(&apiAuth); err != nil {
+		retBadReq(err, c)
+		return
+	}
+	// API to common + verify signature
+	dbAuth, err := accountCreationAuthAPIToCommon(&apiAuth)
+	if err != nil {
+		retBadReq(err, c)
+		return
+	}
+	// Insert to DB
+	if err := l2.AddAccountCreationAuth(dbAuth); err != nil {
+		retSQLErr(err, c)
+		return
+	}
+	// Return OK
+	c.Status(http.StatusOK)
 }
 
 func getAccountCreationAuth(c *gin.Context) {
+	// Get hezEthereumAddress
+	addr, err := parseParamHezEthAddr(c)
+	if err != nil {
+		retBadReq(err, c)
+		return
+	}
+	// Fetch auth from l2DB
+	dbAuth, err := l2.GetAccountCreationAuth(*addr)
+	if err != nil {
+		retSQLErr(err, c)
+		return
+	}
+	apiAuth := accountCreationAuthToAPI(dbAuth)
+	// Build succesfull response
+	c.JSON(http.StatusOK, apiAuth)
 }
 
 func postPoolTx(c *gin.Context) {

api/parsers.go

@@ -310,6 +310,7 @@ func hezStringToBJJ(bjjStr, name string) (*babyjub.PublicKey, error) {
 	}
 	return bjj, nil
 }
+
 func parseEthAddr(c paramer, name string) (*ethCommon.Address, error) {
 	addrStr := c.Param(name)
 	if addrStr == "" {
@@ -319,3 +320,9 @@ func parseEthAddr(c paramer, name string) (*ethCommon.Address, error) {
 	err := addr.UnmarshalText([]byte(addrStr))
 	return &addr, err
 }
+
+func parseParamHezEthAddr(c paramer) (*ethCommon.Address, error) {
+	const name = "hermezEthereumAddress"
+	addrStr := c.Param(name)
+	return hezStringToEthAddr(addrStr, name)
+}

api/swagger.yml

@@ -76,7 +76,7 @@ paths:
         content:
           application/json:
             schema:
-              $ref: '#/components/schemas/AccountCreationAuthorization'
+              $ref: '#/components/schemas/AccountCreationAuthorizationPost'
       responses:
         '200':
           description: Successful operation.
@@ -1251,7 +1251,7 @@ components:
           $ref: '#/components/schemas/Nonce'
         signature:
           allOf:
-            - $ref: '#/components/schemas/Signature'
+            - $ref: '#/components/schemas/BJJSignature'
             - description: Signature of the transaction. More info [here](https://idocs.hermez.io/#/spec/zkrollup/README?id=l2a-idl2).
             - example: "72024a43f546b0e1d9d5d7c4c30c259102a9726363adcc4ec7b6aea686bcb5116f485c5542d27c4092ae0ceaf38e3bb44417639bd2070a58ba1aa1aab9d92c03"
         requestFromAccountIndex:
@@ -1346,7 +1346,7 @@ components:
           $ref: '#/components/schemas/PoolL2TransactionState'
         signature:
           allOf:
-            - $ref: '#/components/schemas/Signature'
+            - $ref: '#/components/schemas/BJJSignature'
             - description: Signature of the transaction. More info [here](https://idocs.hermez.io/#/spec/zkrollup/README?id=l2a-idl2).
             - example: "72024a43f546b0e1d9d5d7c4c30c259102a9726363adcc4ec7b6aea686bcb5116f485c5542d27c4092ae0ceaf38e3bb44417639bd2070a58ba1aa1aab9d92c03"
         timestamp:
@@ -1517,7 +1517,12 @@ components:
       - fing
       - fged
       - invl    
-    Signature:
+    ETHSignature:
+      type: string
+      description: Ethereum signature.
+      pattern: "^0x[a-fA-F0-9]{130}$"
+      example: "0xf9161cd688394772d93aa3e7b3f8f9553ca4f94f65b7cece93ed4a239d5c0b4677dca6d1d459e3a5c271a34de735d4664a43e5a8960a9a6e027d12c562dd448e1c"
+    BJJSignature:
       type: string
       description: BabyJubJub compressed signature.
       pattern: "^[a-fA-F0-9]{128}$"
@@ -1528,6 +1533,19 @@ components:
       minimum: 0
       maximum: 4294967295
       example: 5432
+    AccountCreationAuthorizationPost:
+      type: object
+      properties:
+        hezEthereumAddress:
+          $ref: '#/components/schemas/HezEthereumAddress'
+        bjj:
+          $ref: '#/components/schemas/BJJ'
+        signature:
+          $ref: '#/components/schemas/ETHSignature'
+      required:
+      - hezEthereumAddress
+      - bjj
+      - signature
     AccountCreationAuthorization:
       type: object
       properties:
@@ -1539,12 +1557,10 @@ components:
         bjj:
           $ref: '#/components/schemas/BJJ'
         signature:
-          allOf:
+          $ref: '#/components/schemas/ETHSignature'
-            - $ref: '#/components/schemas/Signature'
-            - description: Signature of the auth message. More info [here](https://idocs.hermez.io/#/spec/zkrollup/README?id=regular-rollup-account).
-            - example: "72024a43f546b0e1d9d5d7c4c30c259102a9726363adcc4ec7b6aea686bcb5116f485c5542d27c4092ae0ceaf38e3bb44417639bd2070a58ba1aa1aab9d92c03"
       required:
-      - ethereumAddress
+      - timestamp
+      - hezEthereumAddress
       - bjj
       - signature
     HistoryTransaction:

common/accountcreationauths.go

@@ -4,6 +4,7 @@ import (
 	"time"
 
 	ethCommon "github.com/ethereum/go-ethereum/common"
+	ethCrypto "github.com/ethereum/go-ethereum/crypto"
 	"github.com/iden3/go-iden3-crypto/babyjub"
 )
 
@@ -14,3 +15,36 @@ type AccountCreationAuth struct {
 	Signature []byte             `meddler:"signature"`
 	Timestamp time.Time          `meddler:"timestamp,utctime"`
 }
+
+// HashToSign builds the hash to be signed using BJJ pub key and the constant message
+func (a *AccountCreationAuth) HashToSign() ([]byte, error) {
+	// Calculate message to be signed
+	const msg = "I authorize this babyjubjub key for hermez rollup account creation"
+	comp, err := a.BJJ.Compress().MarshalText()
+	if err != nil {
+		return nil, err
+	}
+	// Hash message (msg || compressed-bjj)
+	return ethCrypto.Keccak256Hash([]byte(msg), comp).Bytes(), nil
+}
+
+// VerifySignature ensures that the Signature is done with the specified EthAddr
+func (a *AccountCreationAuth) VerifySignature() bool {
+	// Calculate hash to be signed
+	msg, err := a.HashToSign()
+	if err != nil {
+		return false
+	}
+	// Get public key from Signature
+	pubKBytes, err := ethCrypto.Ecrecover(msg, a.Signature)
+	if err != nil {
+		return false
+	}
+	pubK, err := ethCrypto.UnmarshalPubkey(pubKBytes)
+	if err != nil {
+		return false
+	}
+	// Get addr from pubK
+	addr := ethCrypto.PubkeyToAddress(*pubK)
+	return addr == a.EthAddr
+}

db/l2db/l2db.go

@@ -46,7 +46,13 @@ func (l2db *L2DB) DB() *sqlx.DB {
 
 // AddAccountCreationAuth inserts an account creation authorization into the DB
 func (l2db *L2DB) AddAccountCreationAuth(auth *common.AccountCreationAuth) error {
-	return meddler.Insert(l2db.db, "account_creation_auth", auth)
+	// return meddler.Insert(l2db.db, "account_creation_auth", auth)
+	_, err := l2db.db.Exec(
+		`INSERT INTO account_creation_auth (eth_addr, bjj, signature)
+		VALUES ($1, $2, $3);`,
+		auth.EthAddr, auth.BJJ, auth.Signature,
+	)
+	return err
 }
 
 // GetAccountCreationAuth returns an account creation authorization into the DB

test/l2db.go

@@ -1,11 +1,7 @@
 package test
 
 import (
-	"math/big"
+	ethCrypto "github.com/ethereum/go-ethereum/crypto"
-	"strconv"
-	"time"
-
-	ethCommon "github.com/ethereum/go-ethereum/common"
 	"github.com/hermeznetwork/hermez-node/common"
 	"github.com/iden3/go-iden3-crypto/babyjub"
 	"github.com/jmoiron/sqlx"
@@ -84,13 +80,28 @@ func GenPoolTxs(n int, tokens []common.Token) []*common.PoolL2Tx {
 func GenAuths(nAuths int) []*common.AccountCreationAuth {
 	auths := []*common.AccountCreationAuth{}
 	for i := 0; i < nAuths; i++ {
-		privK := babyjub.NewRandPrivKey()
+		// Generate keys
-		auths = append(auths, &common.AccountCreationAuth{
+		ethPrivK, err := ethCrypto.GenerateKey()
-			EthAddr:   ethCommon.BigToAddress(big.NewInt(int64(i))),
+		if err != nil {
-			BJJ:       privK.Public(),
+			panic(err)
-			Signature: []byte(strconv.Itoa(i)),
+		}
-			Timestamp: time.Now(),
+		bjjPrivK := babyjub.NewRandPrivKey()
-		})
+		// Generate auth
+		auth := &common.AccountCreationAuth{
+			EthAddr: ethCrypto.PubkeyToAddress(ethPrivK.PublicKey),
+			BJJ:     bjjPrivK.Public(),
+		}
+		// Sign
+		h, err := auth.HashToSign()
+		if err != nil {
+			panic(err)
+		}
+		signature, err := ethCrypto.Sign(h, ethPrivK)
+		if err != nil {
+			panic(err)
+		}
+		auth.Signature = signature
+		auths = append(auths, auth)
 	}
 	return auths
 }

test/l2db_test.go

@@ -0,0 +1,15 @@
+package test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGenAuths(t *testing.T) {
+	const nAuths = 5
+	auths := GenAuths(nAuths)
+	for _, auth := range auths {
+		assert.True(t, auth.VerifySignature())
+	}
+}