| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef REMOTING_HOST_DNS_BLACKHOLE_CHECKER_H_ |
| #define REMOTING_HOST_DNS_BLACKHOLE_CHECKER_H_ |
| |
| #include "net/url_request/url_fetcher_delegate.h" |
| |
| #include "base/callback.h" |
| #include "base/macros.h" |
| |
| namespace net { |
| class URLRequestContextGetter; |
| } // namespace net |
| |
| namespace remoting { |
| |
| // This is the default prefix that is prepended to the kTalkGadgetUrl to form |
| // the complete talkgadget URL used by the host. Policy settings allow admins |
| // to change the prefix that is used. |
| extern const char kDefaultHostTalkGadgetPrefix[]; |
| |
| class DnsBlackholeChecker : public net::URLFetcherDelegate { |
| public: |
| DnsBlackholeChecker( |
| const scoped_refptr<net::URLRequestContextGetter>& request_context_getter, |
| std::string talkgadget_prefix); |
| ~DnsBlackholeChecker() override; |
| |
| // net::URLFetcherDelegate interface. |
| void OnURLFetchComplete(const net::URLFetcher* source) override; |
| |
| // Initiates a check the verify that the host talkgadget has not been "DNS |
| // blackholed" to prevent connections. If this is called again before the |
| // callback has been called, then the second call is ignored. |
| void CheckForDnsBlackhole(const base::Callback<void(bool)>& callback); |
| |
| private: |
| // URL request context getter to use to create the URL fetcher. |
| scoped_refptr<net::URLRequestContextGetter> url_request_context_getter_; |
| |
| // URL fetcher used to verify access to the host talkgadget. |
| std::unique_ptr<net::URLFetcher> url_fetcher_; |
| |
| // The string pre-pended to '.talkgadget.google.com' to create the full |
| // talkgadget domain name for the host. |
| std::string talkgadget_prefix_; |
| |
| // Called with the results of the connection check. |
| base::Callback<void(bool)> callback_; |
| |
| DISALLOW_COPY_AND_ASSIGN(DnsBlackholeChecker); |
| }; |
| |
| } // namespace remoting |
| |
| #endif // REMOTING_HOST_DNS_BLACKHOLE_CHECKER_H_ |