Add email_verified_code to bypass 2FA by email

It will allow the cloudery to inform the stack that it has already
checked that the user can receives email on their address.

assets/scripts/login.js

@@ -11,6 +11,7 @@
   const loginField = d.getElementById('login-field')
   const longRunCheckbox = d.getElementById('long-run-session')
   const trustedTokenInput = d.getElementById('trusted-device-token')
+  const emailVerifiedCodeInput = d.getElementById('email_verified_code')
   const magicCodeInput = d.getElementById('magic_code')
 
   // Set the trusted device token from the localstorage in the form if it exists
@@ -44,6 +45,7 @@
         const data = new URLSearchParams()
         data.append('passphrase', pass)
         data.append('trusted-device-token', trustedTokenInput.value)
+        data.append('email_verified_code', emailVerifiedCodeInput.value)
         data.append('long-run-session', longRun)
         data.append('redirect', redirect)
         data.append('csrf_token', csrfTokenInput.value)

assets/templates/login.html

@@ -22,6 +22,7 @@
       <input id="redirect" type="hidden" name="redirect" value="{{.Redirect}}" />
       <input id="csrf_token" type="hidden" name="csrf_token" value="{{.CSRF}}" />
       <input id="trusted-device-token" type="hidden" name="trusted-device-token" value="" />
+      <input id="email_verified_code" type="hidden" name="email_verified_code" value="{{.EmailVerifiedCode}}" />
       <main class="wrapper">
 
         <header class="wrapper-top">

docs/admin.md

@@ -252,6 +252,33 @@ Content-Type: application/json
 }
 ```
 
+### POST /instances/:domain/email_verified_code
+
+Creates an email_verified_code that can be used on the given instance to avoid
+the 2FA by email.
+
+#### Request
+
+```http
+POST /instances/alice.cozy.localhost/email_verified_code HTTP/1.1
+```
+
+#### Response
+
+```http
+HTTP/1.1 200 OK
+Content-Type: application/json
+```
+
+```json
+{
+  "email_verified_code": "jBPF5Kvpv1oztdaSgdA2315hVpAf6BCd"
+}
+```
+
+Note: if the two factor authentication by email is not enabled on this
+instance, it will return a 400 Bad Request error.
+
 ### DELETE /instances/:domain/sessions
 
 Delete the databases for io.cozy.sessions and io.cozy.sessions.logins.

model/instance/auth.go

@@ -19,6 +19,7 @@ const (
 	RegisterTokenLen      = 16
 	PasswordResetTokenLen = 16
 	SessionCodeLen        = 32
+	EmailVerifiedCodeLen  = 32
 	SessionSecretLen      = 64
 	MagicLinkCodeLen      = 32
 	OauthSecretLen        = 128
@@ -204,3 +205,19 @@ func (i *Instance) CreateSessionCode() (string, error) {
 func (i *Instance) CheckAndClearSessionCode(code string) bool {
 	return GetStore().CheckAndClearSessionCode(i, code)
 }
+
+// CreateEmailVerifiedCode returns an email_verified_code that can be used to
+// avoid the 2FA by email.
+func (i *Instance) CreateEmailVerifiedCode() (string, error) {
+	code := crypto.GenerateRandomString(EmailVerifiedCodeLen)
+	store := GetStore()
+	if err := store.SaveEmailVerfiedCode(i, code); err != nil {
+		return "", err
+	}
+	return code, nil
+}
+
+// CheckEmailVerifiedCode will return true if the email verified code is valid.
+func (i *Instance) CheckEmailVerifiedCode(code string) bool {
+	return GetStore().CheckEmailVerifiedCode(i, code)
+}

model/instance/store.go

@@ -13,11 +13,16 @@ import (
 // Store is an object to store and retrieve session codes.
 type Store interface {
 	SaveSessionCode(db prefixer.Prefixer, code string) error
+	SaveEmailVerfiedCode(db prefixer.Prefixer, code string) error
 	CheckAndClearSessionCode(db prefixer.Prefixer, code string) bool
+	CheckEmailVerifiedCode(db prefixer.Prefixer, code string) bool
 }
 
-// storeTTL is the time an entry stay alive (1 week)
-var storeTTL = 7 * 24 * time.Hour
+// sessionCodeTTL is the time an entry for a session_code stays alive (1 week)
+var sessionCodeTTL = 7 * 24 * time.Hour
+
+// emailVerifiedCodeTTL is the time an entry for an email_verified_code stays alive
+var emailVerifiedCodeTTL = 15 * time.Minute
 
 // storeCleanInterval is the time interval between each cleanup.
 var storeCleanInterval = 1 * time.Hour
@@ -67,29 +72,59 @@ func (s *memStore) cleaner() {
 func (s *memStore) SaveSessionCode(db prefixer.Prefixer, code string) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	s.vals[code] = time.Now().Add(storeTTL)
+	key := sessionCodeKey(db, code)
+	s.vals[key] = time.Now().Add(sessionCodeTTL)
+	return nil
+}
+
+func (s *memStore) SaveEmailVerfiedCode(db prefixer.Prefixer, code string) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	key := emailVerifiedCodeKey(db, code)
+	s.vals[key] = time.Now().Add(emailVerifiedCodeTTL)
 	return nil
 }
 
 func (s *memStore) CheckAndClearSessionCode(db prefixer.Prefixer, code string) bool {
 	s.mu.Lock()
 	defer s.mu.Unlock()
-	exp, ok := s.vals[code]
+	key := sessionCodeKey(db, code)
+	exp, ok := s.vals[key]
 	if !ok {
 		return false
 	}
-	delete(s.vals, code)
+	delete(s.vals, key)
 	return time.Now().Before(exp)
 }
 
+func (s *memStore) CheckEmailVerifiedCode(db prefixer.Prefixer, code string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	key := emailVerifiedCodeKey(db, code)
+	exp, ok := s.vals[key]
+	if !ok {
+		return false
+	}
+	if time.Now().After(exp) {
+		delete(s.vals, key)
+		return false
+	}
+	return true
+}
+
 type redisStore struct {
 	c   redis.UniversalClient
 	ctx context.Context
 }
 
 func (s *redisStore) SaveSessionCode(db prefixer.Prefixer, code string) error {
 	key := sessionCodeKey(db, code)
-	return s.c.Set(s.ctx, key, "1", storeTTL).Err()
+	return s.c.Set(s.ctx, key, "1", sessionCodeTTL).Err()
+}
+
+func (s *redisStore) SaveEmailVerfiedCode(db prefixer.Prefixer, code string) error {
+	key := emailVerifiedCodeKey(db, code)
+	return s.c.Set(s.ctx, key, "1", emailVerifiedCodeTTL).Err()
 }
 
 func (s *redisStore) CheckAndClearSessionCode(db prefixer.Prefixer, code string) bool {
@@ -98,6 +133,16 @@ func (s *redisStore) CheckAndClearSessionCode(db prefixer.Prefixer, code string)
 	return err == nil && n > 0
 }
 
+func (s *redisStore) CheckEmailVerifiedCode(db prefixer.Prefixer, code string) bool {
+	key := emailVerifiedCodeKey(db, code)
+	n, err := s.c.Exists(s.ctx, key).Result()
+	return err == nil && n > 0
+}
+
 func sessionCodeKey(db prefixer.Prefixer, suffix string) string {
 	return db.DBPrefix() + ":sessioncode:" + suffix
 }
+
+func emailVerifiedCodeKey(db prefixer.Prefixer, suffix string) string {
+	return db.DBPrefix() + ":emailverifiedcode:" + suffix
+}

web/auth/auth.go

@@ -95,9 +95,12 @@ func Home(c echo.Context) error {
 		}
 	}
 
-	var params url.Values
+	params := make(url.Values)
 	if jwt := c.QueryParam("jwt"); jwt != "" {
-		params = url.Values{"jwt": {jwt}}
+		params.Add("jwt", jwt)
+	}
+	if code := c.QueryParam("email_verified_code"); code != "" {
+		params.Add("email_verified_code", code)
 	}
 	return c.Redirect(http.StatusSeeOther, instance.PageURL("/auth/login", params))
 }
@@ -123,6 +126,13 @@ func isTrustedDevice(c echo.Context, inst *instance.Instance) bool {
 	return inst.ValidateTwoFactorTrustedDeviceSecret(c.Request(), trustedDeviceToken)
 }
 
+// hasEmailVerified checks if the email has already been verified, and if it is
+// the case, the stack can skip the 2FA by email.
+func hasEmailVerified(c echo.Context, inst *instance.Instance) bool {
+	code := c.FormValue("email_verified_code")
+	return inst.CheckEmailVerifiedCode(code)
+}
+
 func getLogoutURL(context string) string {
 	auth := config.GetConfig().Authentication
 	delegated, _ := auth[context].(map[string]interface{})
@@ -196,23 +206,24 @@ func renderLoginForm(c echo.Context, i *instance.Instance, code int, credsErrors
 	}
 
 	return c.Render(code, "login.html", echo.Map{
-		"TemplateTitle":    i.TemplateTitle(),
-		"Domain":           i.ContextualDomain(),
-		"ContextName":      i.ContextName,
-		"Locale":           i.Locale,
-		"Favicon":          middlewares.Favicon(i),
-		"CryptoPolyfill":   middlewares.CryptoPolyfill(c),
-		"BottomNavBar":     middlewares.BottomNavigationBar(c),
-		"Iterations":       iterations,
-		"Salt":             string(i.PassphraseSalt()),
-		"Title":            title,
-		"PasswordHelp":     help,
-		"CredentialsError": credsErrors,
-		"Redirect":         redirectStr,
-		"CSRF":             c.Get("csrf"),
-		"MagicLink":        i.MagicLink,
-		"OAuth":            hasOAuth,
-		"FranceConnect":    hasFranceConnect,
+		"TemplateTitle":     i.TemplateTitle(),
+		"Domain":            i.ContextualDomain(),
+		"ContextName":       i.ContextName,
+		"Locale":            i.Locale,
+		"Favicon":           middlewares.Favicon(i),
+		"CryptoPolyfill":    middlewares.CryptoPolyfill(c),
+		"BottomNavBar":      middlewares.BottomNavigationBar(c),
+		"Iterations":        iterations,
+		"Salt":              string(i.PassphraseSalt()),
+		"Title":             title,
+		"PasswordHelp":      help,
+		"CredentialsError":  credsErrors,
+		"Redirect":          redirectStr,
+		"CSRF":              c.Get("csrf"),
+		"EmailVerifiedCode": c.QueryParam("email_verified_code"),
+		"MagicLink":         i.MagicLink,
+		"OAuth":             hasOAuth,
+		"FranceConnect":     hasFranceConnect,
 	})
 }
 
@@ -342,7 +353,8 @@ func login(c echo.Context) error {
 		// check that the mail has been confirmed. If not, 2FA is not
 		// activated.
 		// If device is trusted, skip the 2FA.
-		if inst.HasAuthMode(instance.TwoFactorMail) && !isTrustedDevice(c, inst) {
+		// If the email has already been verified, skip the 2FA too.
+		if inst.HasAuthMode(instance.TwoFactorMail) && !isTrustedDevice(c, inst) && !hasEmailVerified(c, inst) {
 			twoFactorToken, err := lifecycle.SendTwoFactorPasscode(inst)
 			if err != nil {
 				return err

web/instances/instances.go

@@ -379,6 +379,40 @@ func createSessionCode(c echo.Context) error {
 	})
 }
 
+func createEmailVerifiedCode(c echo.Context) error {
+	domain := c.Param("domain")
+	inst, err := lifecycle.GetInstance(domain)
+	if err != nil {
+		return err
+	}
+
+	if !inst.HasAuthMode(instance.TwoFactorMail) {
+		return jsonapi.BadRequest(errors.New("2FA by email is not enabled on this instance"))
+	}
+
+	code, err := inst.CreateEmailVerifiedCode()
+	if err != nil {
+		return c.JSON(http.StatusInternalServerError, echo.Map{
+			"error": err,
+		})
+	}
+
+	req := c.Request()
+	var ip string
+	if forwardedFor := req.Header.Get(echo.HeaderXForwardedFor); forwardedFor != "" {
+		ip = strings.TrimSpace(strings.SplitN(forwardedFor, ",", 2)[0])
+	}
+	if ip == "" {
+		ip = strings.Split(req.RemoteAddr, ":")[0]
+	}
+	inst.Logger().WithField("nspace", "loginaudit").
+		Infof("New email_verified_code created from %s at %s", ip, time.Now())
+
+	return c.JSON(http.StatusCreated, echo.Map{
+		"email_verified_code": code,
+	})
+}
+
 func cleanSessions(c echo.Context) error {
 	domain := c.Param("domain")
 	inst, err := lifecycle.GetInstance(domain)
@@ -650,6 +684,7 @@ func Routes(router *echo.Group) {
 	router.POST("/:domain/auth-mode", setAuthMode)
 	router.POST("/:domain/magic_link", createMagicLink)
 	router.POST("/:domain/session_code", createSessionCode)
+	router.POST("/:domain/email_verified_code", createEmailVerifiedCode)
 	router.DELETE("/:domain/sessions", cleanSessions)
 
 	// Advanced features for instances