Shelf Host Validation

Middleware that protects Shelf and DartFrog servers from DNS Rebinding attacks by validating Host and Referer [sic] headers from incoming requests. If a request doesn't contain a whitelisted Host/Referer header, shelf_host_validation will respond with a 403 Forbidden HTTP error. Inspired by https://github.com/brannondorsey/host-validation

Installing

dart pub add shelf_enforces_ssl

Usage

Parameters:

• [hosts] is a list of allowed hosts, can be a RegExp or a String
• [referer] is list of allowed referer, can be a RegExp or a String
• [mode] is the [ValidationMode], either or both
• [errorResponse] is the [Response] which is returned if the validation fails

As shelf middleware

import 'package:shelf_host_validation/shelf_host_validation.dart';

var handler = const Pipeline()
    .addMiddleware(
      validateHost(
        hosts: ['trusted-host.com'],
        referers: [
          'http://trusted-host.com/#.php',
          RegExp(r'^https:\/\/'),
        ],
      ),
    )
    .addMiddleware(logRequests())
    .addHandler(_echoRequest);

As dart_frog middleware

import 'package:shelf_host_validation/shelf_host_validation.dart';

Handler enforceSSL(Handler handler) {
  return handler.use(
    fromShelfMiddleware(
      validateHost(
        hosts: ['trusted-host.com'],
        referers: [
          'http://trusted-host.com/#.php',
          RegExp(r'^https:\/\/'),
        ],
      ),
    ),
  );
}