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 "content/browser/browser_url_handler_impl.h"
6
7#include "base/strings/string_util.h"
8#include "content/browser/frame_host/debug_urls.h"
9#include "content/browser/webui/web_ui_impl.h"
10#include "content/public/browser/content_browser_client.h"
11#include "content/public/common/url_constants.h"
12#include "url/gurl.h"
13
14namespace content {
15
16// Handles rewriting view-source URLs for what we'll actually load.
17static bool HandleViewSource(GURL* url, BrowserContext* browser_context) {
18  if (url->SchemeIs(kViewSourceScheme)) {
19    // Load the inner URL instead.
20    *url = GURL(url->GetContent());
21
22    // Bug 26129: limit view-source to view the content and not any
23    // other kind of 'active' url scheme like 'javascript' or 'data'.
24    static const char* const default_allowed_sub_schemes[] = {
25        url::kHttpScheme,
26        url::kHttpsScheme,
27        url::kFtpScheme,
28        kChromeDevToolsScheme,
29        kChromeUIScheme,
30        url::kFileScheme,
31        url::kFileSystemScheme
32    };
33
34    // Merge all the schemes for which view-source is allowed by default, with
35    // the WebUI schemes defined by the ContentBrowserClient.
36    std::vector<std::string> all_allowed_sub_schemes;
37    for (size_t i = 0; i < arraysize(default_allowed_sub_schemes); ++i)
38      all_allowed_sub_schemes.push_back(default_allowed_sub_schemes[i]);
39    GetContentClient()->browser()->GetAdditionalWebUISchemes(
40        &all_allowed_sub_schemes);
41
42    bool is_sub_scheme_allowed = false;
43    for (size_t i = 0; i < all_allowed_sub_schemes.size(); ++i) {
44      if (url->SchemeIs(all_allowed_sub_schemes[i].c_str())) {
45        is_sub_scheme_allowed = true;
46        break;
47      }
48    }
49
50    if (!is_sub_scheme_allowed) {
51      *url = GURL(url::kAboutBlankURL);
52      return false;
53    }
54
55    return true;
56  }
57  return false;
58}
59
60// Turns a non view-source URL into the corresponding view-source URL.
61static bool ReverseViewSource(GURL* url, BrowserContext* browser_context) {
62  // No action necessary if the URL is already view-source:
63  if (url->SchemeIs(kViewSourceScheme))
64    return false;
65
66  url::Replacements<char> repl;
67  repl.SetScheme(kViewSourceScheme,
68                 url::Component(0, strlen(kViewSourceScheme)));
69  repl.SetPath(url->spec().c_str(), url::Component(0, url->spec().size()));
70  *url = url->ReplaceComponents(repl);
71  return true;
72}
73
74static bool DebugURLHandler(GURL* url, BrowserContext* browser_context) {
75  // Circumvent processing URLs that the renderer process will handle.
76  return IsRendererDebugURL(*url);
77}
78
79// static
80BrowserURLHandler* BrowserURLHandler::GetInstance() {
81  return BrowserURLHandlerImpl::GetInstance();
82}
83
84// static
85BrowserURLHandler::URLHandler BrowserURLHandler::null_handler() {
86  // Required for VS2010: http://connect.microsoft.com/VisualStudio/feedback/details/520043/error-converting-from-null-to-a-pointer-type-in-std-pair
87  return NULL;
88}
89
90// static
91BrowserURLHandlerImpl* BrowserURLHandlerImpl::GetInstance() {
92  return Singleton<BrowserURLHandlerImpl>::get();
93}
94
95BrowserURLHandlerImpl::BrowserURLHandlerImpl() {
96  AddHandlerPair(&DebugURLHandler, BrowserURLHandlerImpl::null_handler());
97
98  GetContentClient()->browser()->BrowserURLHandlerCreated(this);
99
100  // view-source:
101  AddHandlerPair(&HandleViewSource, &ReverseViewSource);
102}
103
104BrowserURLHandlerImpl::~BrowserURLHandlerImpl() {
105}
106
107void BrowserURLHandlerImpl::AddHandlerPair(URLHandler handler,
108                                           URLHandler reverse_handler) {
109  url_handlers_.push_back(HandlerPair(handler, reverse_handler));
110}
111
112void BrowserURLHandlerImpl::RewriteURLIfNecessary(
113    GURL* url,
114    BrowserContext* browser_context,
115    bool* reverse_on_redirect) {
116  for (size_t i = 0; i < url_handlers_.size(); ++i) {
117    URLHandler handler = *url_handlers_[i].first;
118    if (handler && handler(url, browser_context)) {
119      *reverse_on_redirect = (url_handlers_[i].second != NULL);
120      return;
121    }
122  }
123}
124
125bool BrowserURLHandlerImpl::ReverseURLRewrite(
126    GURL* url, const GURL& original, BrowserContext* browser_context) {
127  for (size_t i = 0; i < url_handlers_.size(); ++i) {
128    URLHandler reverse_rewriter = *url_handlers_[i].second;
129    if (reverse_rewriter) {
130      GURL test_url(original);
131      URLHandler handler = *url_handlers_[i].first;
132      if (!handler) {
133        if (reverse_rewriter(url, browser_context))
134          return true;
135      } else if (handler(&test_url, browser_context)) {
136        return reverse_rewriter(url, browser_context);
137      }
138    }
139  }
140  return false;
141}
142
143}  // namespace content
144