components/resource_provider/file_utils.cc

   1 // Copyright 2015 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 "components/resource_provider/file_utils.h"
   6
   7 #include "base/files/file_path.h"
   8 #include "base/path_service.h"
   9 #include "base/strings/string_split.h"
  10 #include "base/strings/string_util.h"
  11 #include "url/gurl.h"
  12
  13 namespace resource_provider {
  14 namespace {
  15
  16 bool IsPathNameValid(const std::string& name) {
  17   if (name.empty() || name == "." || name == "..")
  18     return false;
  19
  20   for (auto c : name) {
  21     if (!base::IsAsciiAlpha(c) && !base::IsAsciiDigit(c) &&
  22         c != '_' && c != '.')
  23       return false;
  24   }
  25   return true;
  26 }
  27
  28 }  // namespace
  29
  30 base::FilePath GetPathForApplicationUrl(const GURL& application_url) {
  31   if (application_url.scheme() != "mojo")
  32     return base::FilePath();
  33
  34   std::string path = application_url.path();
  35   base::TrimString(path, "/", &path);
  36
  37   if (!IsPathNameValid(path))
  38     return base::FilePath();
  39
  40   base::FilePath base_path;
  41 #if defined(OS_ANDROID)
  42   PathService::Get(base::DIR_ANDROID_APP_DATA, &base_path);
  43   // |base_path| on android has an additional path, need to go up a level to get
  44   // at other apps resources.
  45   base_path = base_path.DirName();
  46   base_path = base_path.AppendASCII("app_cached_apps");
  47 #else
  48   PathService::Get(base::DIR_EXE, &base_path);
  49 #endif
  50   return base_path.AppendASCII(path).AppendASCII("resources");
  51 }
  52
  53 base::FilePath GetPathForResourceNamed(const base::FilePath& app_path,
  54                                        const std::string& resource_path) {
  55   CHECK(!app_path.empty());
  56
  57   if (resource_path.empty() || resource_path[0] == '/' ||
  58       resource_path[resource_path.size() - 1] == '/' ||
  59       resource_path.find("//") != std::string::npos)
  60     return base::FilePath();
  61
  62   std::vector<std::string> path_components = base::SplitString(
  63       resource_path, "/", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
  64   if (path_components.empty())
  65     return base::FilePath();
  66
  67   base::FilePath result(app_path);
  68   for (const auto& path_component : path_components) {
  69     if (!IsPathNameValid(path_component))
  70       return base::FilePath();
  71     result = result.AppendASCII(path_component);
  72   }
  73   return result;
  74 }
  75
  76 }  // namespace resource_provider