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/file_util.h"
14 #include "base/files/file_path.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
34 namespace extensions {
35
36 namespace keys = manifest_keys;
37
38 using base::Time;
39
40 namespace {
41
42 const 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.
GenerateKey(const GURL & app_url)51 std::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.
ConvertTimeToExtensionVersion(const Time & create_time)64 std::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
ConvertWebAppToExtension(const WebApplicationInfo & web_app,const Time & create_time,const base::FilePath & extensions_dir)86 scoped_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.config() == SkBitmap::kNo_Config)
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