Strip JWT base64 padding before parsing. #560

Author: danopia

providers/google.go

@@ -67,7 +67,8 @@ func emailFromIdToken(idToken string) (string, error) {
 	// id_token is a base64 encode ID token payload
 	// https://developers.google.com/accounts/docs/OAuth2Login#obtainuserinfo
 	jwt := strings.Split(idToken, ".")
-	b, err := base64.RawURLEncoding.DecodeString(jwt[1])
+	jwtData := strings.TrimSuffix(jwt[1], "=")
+	b, err := base64.RawURLEncoding.DecodeString(jwtData)
 	if err != nil {
 		return "", err
 	}