VW: fix login (#2430)

vehicle/vw/forms.go

@@ -1,8 +1,12 @@
 package vw
 
 import (
+	"encoding/json"
 	"errors"
+	"fmt"
 	"io"
+	"regexp"
+	"strings"
 
 	"github.com/PuerkitoBio/goquery"
 )
@@ -53,3 +57,38 @@ func FormValues(reader io.Reader, id string) (FormVars, error) {
 
 	return vars, err
 }
+
+type CredentialParams struct {
+	TemplateModel struct {
+		Hmac          string `json:"hmac"`
+		RelayState    string `json:"relayState"`
+		PostAction    string `json:"postAction"`
+		IdentifierUrl string `json:"identifierUrl"`
+		Error         string `json:"error"`
+	} `json:"templateModel"`
+	CurrentLocale     string `json:"currentLocale"`
+	CsrfParameterName string `json:"csrf_parameterName"`
+	CsrfToken         string `json:"csrf_token"`
+}
+
+func ParseCredentialsPage(r io.ReadCloser) (CredentialParams, error) {
+	var res CredentialParams
+
+	buf := new(strings.Builder)
+	if _, err := io.Copy(buf, r); err != nil {
+		return res, err
+	}
+
+	re := regexp.MustCompile(`(?s)window._IDK\s*=\s*(.*?);`)
+	match := re.FindAllStringSubmatch(buf.String(), -1)
+
+	tmpl := strings.ReplaceAll(match[0][1], `'`, `"`)
+	for _, v := range []string{`templateModel`, `currentLocale`, `csrf_parameterName`, `csrf_token`} {
+		tmpl = strings.Replace(tmpl, v, fmt.Sprintf(`"%s"`, v), 1)
+	}
+
+	err := json.Unmarshal([]byte(tmpl), &res)
+	fmt.Printf("%+v\n", res)
+
+	return res, err
+}

vehicle/vw/identity.go

@@ -13,6 +13,8 @@ import (
 	"golang.org/x/oauth2"
 )
 
+// https://identity.vwgroup.io/.well-known/openid-configuration
+
 const (
 	// IdentityURI is the VW OIDC identity provider uri
 	IdentityURI = "https://identity.vwgroup.io"

vehicle/vw/tokenprovider.go

@@ -1,6 +1,7 @@
 package vw
 
 import (
+	"errors"
 	"fmt"
 	"net/http"
 	"net/http/cookiejar"
@@ -70,6 +71,8 @@ func (v *IDTokenProvider) Login() (url.Values, error) {
 		resp.Body.Close()
 	}
 
+	var params CredentialParams
+
 	// POST identity.vwgroup.io/signin-service/v1/b7a5bb47-f875-47cf-ab83-2ba3bf6bb738@apps_vw-dilab_com/login/identifier
 	if err == nil {
 		data := url.Values(map[string][]string{
@@ -81,7 +84,7 @@ func (v *IDTokenProvider) Login() (url.Values, error) {
 
 		uri = IdentityURI + vars.Action
 		if resp, err = v.PostForm(uri, data); err == nil {
-			vars, err = FormValues(resp.Body, "form#credentialsForm")
+			params, err = ParseCredentialsPage(resp.Body)
 			resp.Body.Close()
 		}
 	}
@@ -89,17 +92,25 @@ func (v *IDTokenProvider) Login() (url.Values, error) {
 	// POST identity.vwgroup.io/signin-service/v1/b7a5bb47-f875-47cf-ab83-2ba3bf6bb738@apps_vw-dilab_com/login/authenticate
 	if err == nil {
 		data := url.Values(map[string][]string{
-			"_csrf":      {vars.Inputs["_csrf"]},
-			"relayState": {vars.Inputs["relayState"]},
-			"hmac":       {vars.Inputs["hmac"]},
+			"_csrf":      {params.CsrfToken},
+			"relayState": {params.TemplateModel.RelayState},
+			"hmac":       {params.TemplateModel.Hmac},
 			"email":      {v.user},
 			"password":   {v.password},
 		})
 
-		uri = IdentityURI + vars.Action
+		// reuse url from identifier step before
+		uri = strings.ReplaceAll(uri, params.TemplateModel.IdentifierUrl, params.TemplateModel.PostAction)
+
 		if resp, err = v.PostForm(uri, data); err == nil {
 			resp.Body.Close()
 
+			if resp.StatusCode >= http.StatusBadRequest {
+				err = errors.New(resp.Status)
+			}
+		}
+
+		if err == nil {
 			if e := resp.Request.URL.Query().Get("error"); e != "" {
 				err = fmt.Errorf(e)
 			}