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 "chrome/browser/extensions/convert_web_app.h"
6
7#include <cmath>
8#include <limits>
9#include <string>
10#include <vector>
11
12#include "base/base64.h"
13#include "base/files/file_path.h"
14#include "base/files/file_util.h"
15#include "base/files/scoped_temp_dir.h"
16#include "base/json/json_file_value_serializer.h"
17#include "base/logging.h"
18#include "base/numerics/safe_conversions.h"
19#include "base/path_service.h"
20#include "base/strings/stringprintf.h"
21#include "base/strings/utf_string_conversions.h"
22#include "base/time/time.h"
23#include "chrome/common/chrome_paths.h"
24#include "chrome/common/web_application_info.h"
25#include "crypto/sha2.h"
26#include "extensions/common/constants.h"
27#include "extensions/common/extension.h"
28#include "extensions/common/file_util.h"
29#include "extensions/common/manifest_constants.h"
30#include "third_party/skia/include/core/SkBitmap.h"
31#include "ui/gfx/codec/png_codec.h"
32#include "url/gurl.h"
33
34namespace extensions {
35
36namespace keys = manifest_keys;
37
38using base::Time;
39
40namespace {
41
42const char kIconsDirName[] = "icons";
43
44// Create the public key for the converted web app.
45//
46// Web apps are not signed, but the public key for an extension doubles as
47// its unique identity, and we need one of those. A web app's unique identity
48// is its manifest URL, so we hash that to create a public key. There will be
49// no corresponding private key, which means that these extensions cannot be
50// auto-updated using ExtensionUpdater.
51std::string GenerateKey(const GURL& app_url) {
52  char raw[crypto::kSHA256Length] = {0};
53  std::string key;
54  crypto::SHA256HashString(app_url.spec().c_str(), raw,
55                           crypto::kSHA256Length);
56  base::Base64Encode(std::string(raw, crypto::kSHA256Length), &key);
57  return key;
58}
59
60}  // namespace
61
62// Generates a version for the converted app using the current date. This isn't
63// really needed, but it seems like useful information.
64std::string ConvertTimeToExtensionVersion(const Time& create_time) {
65  Time::Exploded create_time_exploded;
66  create_time.UTCExplode(&create_time_exploded);
67
68  double micros = static_cast<double>(
69      (create_time_exploded.millisecond * Time::kMicrosecondsPerMillisecond) +
70      (create_time_exploded.second * Time::kMicrosecondsPerSecond) +
71      (create_time_exploded.minute * Time::kMicrosecondsPerMinute) +
72      (create_time_exploded.hour * Time::kMicrosecondsPerHour));
73  double day_fraction = micros / Time::kMicrosecondsPerDay;
74  double stamp = day_fraction * std::numeric_limits<uint16>::max();
75
76  // Ghetto-round, since VC++ doesn't have round().
77  stamp = stamp >= (floor(stamp) + 0.5) ? (stamp + 1) : stamp;
78
79  return base::StringPrintf("%i.%i.%i.%i",
80                            create_time_exploded.year,
81                            create_time_exploded.month,
82                            create_time_exploded.day_of_month,
83                            static_cast<uint16>(stamp));
84}
85
86scoped_refptr<Extension> ConvertWebAppToExtension(
87    const WebApplicationInfo& web_app,
88    const Time& create_time,
89    const base::FilePath& extensions_dir) {
90  base::FilePath install_temp_dir =
91      file_util::GetInstallTempDir(extensions_dir);
92  if (install_temp_dir.empty()) {
93    LOG(ERROR) << "Could not get path to profile temporary directory.";
94    return NULL;
95  }
96
97  base::ScopedTempDir temp_dir;
98  if (!temp_dir.CreateUniqueTempDirUnderPath(install_temp_dir)) {
99    LOG(ERROR) << "Could not create temporary directory.";
100    return NULL;
101  }
102
103  // Create the manifest
104  scoped_ptr<base::DictionaryValue> root(new base::DictionaryValue);
105  root->SetString(keys::kPublicKey, GenerateKey(web_app.app_url));
106  root->SetString(keys::kName, base::UTF16ToUTF8(web_app.title));
107  root->SetString(keys::kVersion, ConvertTimeToExtensionVersion(create_time));
108  root->SetString(keys::kDescription, base::UTF16ToUTF8(web_app.description));
109  root->SetString(keys::kLaunchWebURL, web_app.app_url.spec());
110
111  // Add the icons.
112  base::DictionaryValue* icons = new base::DictionaryValue();
113  root->Set(keys::kIcons, icons);
114  for (size_t i = 0; i < web_app.icons.size(); ++i) {
115    std::string size = base::StringPrintf("%i", web_app.icons[i].width);
116    std::string icon_path = base::StringPrintf("%s/%s.png", kIconsDirName,
117                                               size.c_str());
118    icons->SetString(size, icon_path);
119  }
120
121  // Write the manifest.
122  base::FilePath manifest_path = temp_dir.path().Append(kManifestFilename);
123  JSONFileValueSerializer serializer(manifest_path);
124  if (!serializer.Serialize(*root)) {
125    LOG(ERROR) << "Could not serialize manifest.";
126    return NULL;
127  }
128
129  // Write the icon files.
130  base::FilePath icons_dir = temp_dir.path().AppendASCII(kIconsDirName);
131  if (!base::CreateDirectory(icons_dir)) {
132    LOG(ERROR) << "Could not create icons directory.";
133    return NULL;
134  }
135  for (size_t i = 0; i < web_app.icons.size(); ++i) {
136    // Skip unfetched bitmaps.
137    if (web_app.icons[i].data.colorType() == kUnknown_SkColorType)
138      continue;
139
140    base::FilePath icon_file = icons_dir.AppendASCII(
141        base::StringPrintf("%i.png", web_app.icons[i].width));
142    std::vector<unsigned char> image_data;
143    if (!gfx::PNGCodec::EncodeBGRASkBitmap(web_app.icons[i].data,
144                                           false,
145                                           &image_data)) {
146      LOG(ERROR) << "Could not create icon file.";
147      return NULL;
148    }
149
150    const char* image_data_ptr = reinterpret_cast<const char*>(&image_data[0]);
151    int size = base::checked_cast<int>(image_data.size());
152    if (base::WriteFile(icon_file, image_data_ptr, size) != size) {
153      LOG(ERROR) << "Could not write icon file.";
154      return NULL;
155    }
156  }
157
158  // Finally, create the extension object to represent the unpacked directory.
159  std::string error;
160  scoped_refptr<Extension> extension = Extension::Create(
161      temp_dir.path(),
162      Manifest::INTERNAL,
163      *root,
164      Extension::FROM_BOOKMARK,
165      &error);
166  if (!extension.get()) {
167    LOG(ERROR) << error;
168    return NULL;
169  }
170
171  temp_dir.Take();  // The caller takes ownership of the directory.
172  return extension;
173}
174
175}  // namespace extensions
176