1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "remoting/host/dns_blackhole_checker.h"
6
7#include "net/url_request/url_fetcher.h"
8#include "net/url_request/url_request_context_getter.h"
9#include "remoting/base/logging.h"
10#include "url/gurl.h"
11
12namespace remoting {
13
14// Default prefix added to the base talkgadget URL.
15const char kDefaultHostTalkGadgetPrefix[] = "chromoting-host";
16
17// The base talkgadget URL.
18const char kTalkGadgetUrl[] = ".talkgadget.google.com/talkgadget/"
19                              "oauth/chrome-remote-desktop-host";
20
21DnsBlackholeChecker::DnsBlackholeChecker(
22    scoped_refptr<net::URLRequestContextGetter> url_request_context_getter,
23    std::string talkgadget_prefix)
24    : url_request_context_getter_(url_request_context_getter),
25      talkgadget_prefix_(talkgadget_prefix) {
26}
27
28DnsBlackholeChecker::~DnsBlackholeChecker() {
29}
30
31// This is called in response to the TalkGadget http request initiated from
32// CheckStatus().
33void DnsBlackholeChecker::OnURLFetchComplete(const net::URLFetcher* source) {
34  int response = source->GetResponseCode();
35  bool allow = false;
36  if (source->GetResponseCode() == 200) {
37    HOST_LOG << "Successfully connected to host talkgadget.";
38    allow = true;
39  } else {
40    HOST_LOG << "Unable to connect to host talkgadget (" << response << ")";
41  }
42  url_fetcher_.reset(NULL);
43  callback_.Run(allow);
44  callback_.Reset();
45}
46
47void DnsBlackholeChecker::CheckForDnsBlackhole(
48    const base::Callback<void(bool)>& callback) {
49  // Make sure we're not currently in the middle of a connection check.
50  if (!url_fetcher_.get()) {
51    DCHECK(callback_.is_null());
52    callback_ = callback;
53    std::string talkgadget_url("https://");
54    if (talkgadget_prefix_.empty()) {
55      talkgadget_url += kDefaultHostTalkGadgetPrefix;
56    } else {
57      talkgadget_url += talkgadget_prefix_;
58    }
59    talkgadget_url += kTalkGadgetUrl;
60    HOST_LOG << "Verifying connection to " << talkgadget_url;
61    url_fetcher_.reset(net::URLFetcher::Create(GURL(talkgadget_url),
62                                               net::URLFetcher::GET, this));
63    url_fetcher_->SetRequestContext(url_request_context_getter_.get());
64    url_fetcher_->Start();
65  } else {
66    HOST_LOG << "Pending connection check";
67  }
68}
69
70}  // namespace remoting
71