webkit/database/database_util.cc

   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 "webkit/database/database_util.h"
   6
   7 #include "base/basictypes.h"
   8 #include "base/utf_string_conversions.h"
   9 #include "third_party/WebKit/Source/Platform/chromium/public/WebString.h"
  10 #include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityOrigin.h"
  11 #include "webkit/database/database_tracker.h"
  12 #include "webkit/database/vfs_backend.h"
  13
  14 namespace webkit_database {
  15
  16 const char DatabaseUtil::kJournalFileSuffix[] = "-journal";
  17
  18 bool DatabaseUtil::CrackVfsFileName(const base::string16& vfs_file_name,
  19                                     base::string16* origin_identifier,
  20                                     base::string16* database_name,
  21                                     base::string16* sqlite_suffix) {
  22   // 'vfs_file_name' is of the form <origin_identifier>/<db_name>#<suffix>.
  23   // <suffix> is optional.
  24   DCHECK(!vfs_file_name.empty());
  25   size_t first_slash_index = vfs_file_name.find('/');
  26   size_t last_pound_index = vfs_file_name.rfind('#');
  27   // '/' and '#' must be present in the string. Also, the string cannot start
  28   // with a '/' (origin_identifier cannot be empty) and '/' must come before '#'
  29   if ((first_slash_index == base::string16::npos) ||
  30       (last_pound_index == base::string16::npos) ||
  31       (first_slash_index == 0) ||
  32       (first_slash_index > last_pound_index)) {
  33     return false;
  34   }
  35
  36   if (origin_identifier)
  37     *origin_identifier = vfs_file_name.substr(0, first_slash_index);
  38   if (database_name) {
  39     *database_name = vfs_file_name.substr(
  40         first_slash_index + 1, last_pound_index - first_slash_index - 1);
  41   }
  42   if (sqlite_suffix) {
  43     *sqlite_suffix = vfs_file_name.substr(
  44         last_pound_index + 1, vfs_file_name.length() - last_pound_index - 1);
  45   }
  46   return true;
  47 }
  48
  49 base::FilePath DatabaseUtil::GetFullFilePathForVfsFile(
  50     DatabaseTracker* db_tracker, const base::string16& vfs_file_name) {
  51   base::string16 origin_identifier;
  52   base::string16 database_name;
  53   base::string16 sqlite_suffix;
  54   if (!CrackVfsFileName(vfs_file_name, &origin_identifier,
  55                         &database_name, &sqlite_suffix)) {
  56     return base::FilePath(); // invalid vfs_file_name
  57   }
  58
  59   base::FilePath full_path = db_tracker->GetFullDBFilePath(
  60       origin_identifier, database_name);
  61   if (!full_path.empty() && !sqlite_suffix.empty()) {
  62     DCHECK(full_path.Extension().empty());
  63     full_path = full_path.InsertBeforeExtensionASCII(
  64         UTF16ToASCII(sqlite_suffix));
  65   }
  66   // Watch out for directory traversal attempts from a compromised renderer.
  67   if (full_path.value().find(FILE_PATH_LITERAL("..")) !=
  68           base::FilePath::StringType::npos)
  69     return base::FilePath();
  70   return full_path;
  71 }
  72
  73 base::string16 DatabaseUtil::GetOriginIdentifier(const GURL& url) {
  74   base::string16 spec = UTF8ToUTF16(url.spec());
  75   return WebKit::WebSecurityOrigin::createFromString(spec).databaseIdentifier();
  76 }
  77
  78 GURL DatabaseUtil::GetOriginFromIdentifier(
  79     const base::string16& origin_identifier) {
  80   WebKit::WebSecurityOrigin web_security_origin =
  81       WebKit::WebSecurityOrigin::createFromDatabaseIdentifier(
  82           origin_identifier);
  83
  84   // We need this work-around for file:/// URIs as
  85   // createFromDatabaseIdentifier returns null origin_url for them.
  86   if (web_security_origin.isUnique()) {
  87     if (origin_identifier.find(UTF8ToUTF16("file__")) == 0)
  88       return GURL("file:///");
  89     return GURL();
  90   }
  91
  92   return GURL(web_security_origin.toString());
  93 }
  94
  95 bool DatabaseUtil::IsValidOriginIdentifier(
  96     const base::string16& origin_identifier) {
  97   base::string16 dotdot = ASCIIToUTF16("..");
  98   char16 forbidden[] = {'\\', '/', '\0'};
  99
 100   base::string16::size_type pos = origin_identifier.find(dotdot);
 101   if (pos == base::string16::npos)
 102     pos = origin_identifier.find_first_of(forbidden, 0, arraysize(forbidden));
 103
 104   return pos == base::string16::npos;
 105 }
 106
 107 }  // namespace webkit_database