net/base/net_util_win.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 "net/base/net_util.h"
   6
   7 #include <iphlpapi.h>
   8 #include <wlanapi.h>
   9
  10 #include <algorithm>
  11
  12 #include "base/files/file_path.h"
  13 #include "base/lazy_instance.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/strings/string_piece.h"
  16 #include "base/strings/string_util.h"
  17 #include "base/strings/sys_string_conversions.h"
  18 #include "base/strings/utf_string_conversions.h"
  19 #include "base/threading/thread_restrictions.h"
  20 #include "base/win/scoped_handle.h"
  21 #include "base/win/windows_version.h"
  22 #include "net/base/escape.h"
  23 #include "net/base/ip_endpoint.h"
  24 #include "net/base/net_errors.h"
  25 #include "url/gurl.h"
  26
  27 namespace {
  28
  29 struct WlanApi {
  30   typedef DWORD (WINAPI *WlanOpenHandleFunc)(
  31       DWORD, VOID*, DWORD*, HANDLE*);
  32   typedef DWORD (WINAPI *WlanEnumInterfacesFunc)(
  33       HANDLE, VOID*, WLAN_INTERFACE_INFO_LIST**);
  34   typedef DWORD (WINAPI *WlanQueryInterfaceFunc)(
  35       HANDLE, const GUID*, WLAN_INTF_OPCODE, VOID*, DWORD*, VOID**,
  36       WLAN_OPCODE_VALUE_TYPE*);
  37   typedef VOID (WINAPI *WlanFreeMemoryFunc)(VOID*);
  38   typedef DWORD (WINAPI *WlanCloseHandleFunc)(HANDLE, VOID*);
  39
  40   WlanApi() : initialized(false) {
  41     // Use an absolute path to load the DLL to avoid DLL preloading attacks.
  42     static const wchar_t* const kDLL = L"%WINDIR%\\system32\\wlanapi.dll";
  43     wchar_t path[MAX_PATH] = {0};
  44     ExpandEnvironmentStrings(kDLL, path, arraysize(path));
  45     module = ::LoadLibraryEx(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
  46     if (!module)
  47       return;
  48
  49     open_handle_func = reinterpret_cast<WlanOpenHandleFunc>(
  50         ::GetProcAddress(module, "WlanOpenHandle"));
  51     enum_interfaces_func = reinterpret_cast<WlanEnumInterfacesFunc>(
  52         ::GetProcAddress(module, "WlanEnumInterfaces"));
  53     query_interface_func = reinterpret_cast<WlanQueryInterfaceFunc>(
  54         ::GetProcAddress(module, "WlanQueryInterface"));
  55     free_memory_func = reinterpret_cast<WlanFreeMemoryFunc>(
  56         ::GetProcAddress(module, "WlanFreeMemory"));
  57     close_handle_func = reinterpret_cast<WlanCloseHandleFunc>(
  58         ::GetProcAddress(module, "WlanCloseHandle"));
  59     initialized = open_handle_func && enum_interfaces_func &&
  60                   query_interface_func && free_memory_func &&
  61                   close_handle_func;
  62   }
  63
  64   HMODULE module;
  65   WlanOpenHandleFunc open_handle_func;
  66   WlanEnumInterfacesFunc enum_interfaces_func;
  67   WlanQueryInterfaceFunc query_interface_func;
  68   WlanFreeMemoryFunc free_memory_func;
  69   WlanCloseHandleFunc close_handle_func;
  70   bool initialized;
  71 };
  72
  73 }  // namespace
  74
  75 namespace net {
  76
  77 bool FileURLToFilePath(const GURL& url, base::FilePath* file_path) {
  78   *file_path = base::FilePath();
  79   std::wstring& file_path_str = const_cast<std::wstring&>(file_path->value());
  80   file_path_str.clear();
  81
  82   if (!url.is_valid())
  83     return false;
  84
  85   std::string path;
  86   std::string host = url.host();
  87   if (host.empty()) {
  88     // URL contains no host, the path is the filename. In this case, the path
  89     // will probably be preceeded with a slash, as in "/C:/foo.txt", so we
  90     // trim out that here.
  91     path = url.path();
  92     size_t first_non_slash = path.find_first_not_of("/\\");
  93     if (first_non_slash != std::string::npos && first_non_slash > 0)
  94       path.erase(0, first_non_slash);
  95   } else {
  96     // URL contains a host: this means it's UNC. We keep the preceeding slash
  97     // on the path.
  98     path = "\\\\";
  99     path.append(host);
 100     path.append(url.path());
 101   }
 102
 103   if (path.empty())
 104     return false;
 105   std::replace(path.begin(), path.end(), '/', '\\');
 106
 107   // GURL stores strings as percent-encoded UTF-8, this will undo if possible.
 108   path = UnescapeURLComponent(path,
 109       UnescapeRule::SPACES | UnescapeRule::URL_SPECIAL_CHARS);
 110
 111   if (!IsStringUTF8(path)) {
 112     // Not UTF-8, assume encoding is native codepage and we're done. We know we
 113     // are giving the conversion function a nonempty string, and it may fail if
 114     // the given string is not in the current encoding and give us an empty
 115     // string back. We detect this and report failure.
 116     file_path_str = base::SysNativeMBToWide(path);
 117     return !file_path_str.empty();
 118   }
 119   file_path_str.assign(UTF8ToWide(path));
 120
 121   // We used to try too hard and see if |path| made up entirely of
 122   // the 1st 256 characters in the Unicode was a zero-extended UTF-16.
 123   // If so, we converted it to 'Latin-1' and checked if the result was UTF-8.
 124   // If the check passed, we converted the result to UTF-8.
 125   // Otherwise, we treated the result as the native OS encoding.
 126   // However, that led to http://crbug.com/4619 and http://crbug.com/14153
 127   return true;
 128 }
 129
 130 bool GetNetworkList(NetworkInterfaceList* networks) {
 131   // GetAdaptersAddresses() may require IO operations.
 132   base::ThreadRestrictions::AssertIOAllowed();
 133   bool is_xp = base::win::GetVersion() < base::win::VERSION_VISTA;
 134   ULONG len = 0;
 135   ULONG flags = is_xp ? GAA_FLAG_INCLUDE_PREFIX : 0;
 136   // First get number of networks.
 137   ULONG result = GetAdaptersAddresses(AF_UNSPEC, flags, NULL, NULL, &len);
 138   if (result != ERROR_BUFFER_OVERFLOW) {
 139     // There are 0 networks.
 140     return true;
 141   }
 142   scoped_ptr<char[]> buf(new char[len]);
 143   IP_ADAPTER_ADDRESSES *adapters =
 144       reinterpret_cast<IP_ADAPTER_ADDRESSES *>(buf.get());
 145   result = GetAdaptersAddresses(AF_UNSPEC, flags, NULL, adapters, &len);
 146   if (result != NO_ERROR) {
 147     LOG(ERROR) << "GetAdaptersAddresses failed: " << result;
 148     return false;
 149   }
 150
 151   for (IP_ADAPTER_ADDRESSES *adapter = adapters; adapter != NULL;
 152        adapter = adapter->Next) {
 153     // Ignore the loopback device.
 154     if (adapter->IfType == IF_TYPE_SOFTWARE_LOOPBACK) {
 155       continue;
 156     }
 157
 158     if (adapter->OperStatus != IfOperStatusUp) {
 159       continue;
 160     }
 161
 162     std::string name = adapter->AdapterName;
 163
 164     for (IP_ADAPTER_UNICAST_ADDRESS* address = adapter->FirstUnicastAddress;
 165          address; address = address->Next) {
 166       int family = address->Address.lpSockaddr->sa_family;
 167       if (family == AF_INET || family == AF_INET6) {
 168         IPEndPoint endpoint;
 169         if (endpoint.FromSockAddr(address->Address.lpSockaddr,
 170                                   address->Address.iSockaddrLength)) {
 171           // XP has no OnLinkPrefixLength field.
 172           size_t net_prefix = is_xp ? 0 : address->OnLinkPrefixLength;
 173           if (is_xp) {
 174             // Prior to Windows Vista the FirstPrefix pointed to the list with
 175             // single prefix for each IP address assigned to the adapter.
 176             // Order of FirstPrefix does not match order of FirstUnicastAddress,
 177             // so we need to find corresponding prefix.
 178             for (IP_ADAPTER_PREFIX* prefix = adapter->FirstPrefix; prefix;
 179                  prefix = prefix->Next) {
 180               int prefix_family = prefix->Address.lpSockaddr->sa_family;
 181               IPEndPoint network_endpoint;
 182               if (prefix_family == family &&
 183                   network_endpoint.FromSockAddr(prefix->Address.lpSockaddr,
 184                       prefix->Address.iSockaddrLength) &&
 185                   IPNumberMatchesPrefix(endpoint.address(),
 186                                         network_endpoint.address(),
 187                                         prefix->PrefixLength)) {
 188                 net_prefix = std::max<size_t>(net_prefix, prefix->PrefixLength);
 189               }
 190             }
 191           }
 192           networks->push_back(
 193               NetworkInterface(adapter->AdapterName, endpoint.address(),
 194                                net_prefix));
 195         }
 196       }
 197     }
 198   }
 199
 200   return true;
 201 }
 202
 203 WifiPHYLayerProtocol GetWifiPHYLayerProtocol() {
 204   static base::LazyInstance<WlanApi>::Leaky lazy_wlanapi =
 205       LAZY_INSTANCE_INITIALIZER;
 206
 207   struct WlanApiHandleTraits {
 208     typedef HANDLE Handle;
 209
 210     static bool CloseHandle(HANDLE handle) {
 211       return lazy_wlanapi.Get().close_handle_func(handle, NULL) ==
 212           ERROR_SUCCESS;
 213     }
 214     static bool IsHandleValid(HANDLE handle) {
 215       return base::win::HandleTraits::IsHandleValid(handle);
 216     }
 217     static HANDLE NullHandle() {
 218       return base::win::HandleTraits::NullHandle();
 219     }
 220   };
 221
 222   typedef base::win::GenericScopedHandle<
 223       WlanApiHandleTraits,
 224       base::win::DummyVerifierTraits> WlanHandle;
 225
 226   struct WlanApiDeleter {
 227     inline void operator()(void* ptr) const {
 228       lazy_wlanapi.Get().free_memory_func(ptr);
 229     }
 230   };
 231
 232   const WlanApi& wlanapi = lazy_wlanapi.Get();
 233   if (!wlanapi.initialized)
 234     return WIFI_PHY_LAYER_PROTOCOL_NONE;
 235
 236   WlanHandle client;
 237   DWORD cur_version = 0;
 238   const DWORD kMaxClientVersion = 2;
 239   DWORD result = wlanapi.open_handle_func(kMaxClientVersion, NULL, &cur_version,
 240                                           client.Receive());
 241   if (result != ERROR_SUCCESS)
 242     return WIFI_PHY_LAYER_PROTOCOL_NONE;
 243
 244   WLAN_INTERFACE_INFO_LIST* interface_list_ptr = NULL;
 245   result = wlanapi.enum_interfaces_func(client, NULL, &interface_list_ptr);
 246   if (result != ERROR_SUCCESS)
 247     return WIFI_PHY_LAYER_PROTOCOL_NONE;
 248   scoped_ptr<WLAN_INTERFACE_INFO_LIST, WlanApiDeleter> interface_list(
 249       interface_list_ptr);
 250
 251   // Assume at most one connected wifi interface.
 252   WLAN_INTERFACE_INFO* info = NULL;
 253   for (unsigned i = 0; i < interface_list->dwNumberOfItems; ++i) {
 254     if (interface_list->InterfaceInfo[i].isState ==
 255         wlan_interface_state_connected) {
 256       info = &interface_list->InterfaceInfo[i];
 257       break;
 258     }
 259   }
 260
 261   if (info == NULL)
 262     return WIFI_PHY_LAYER_PROTOCOL_NONE;
 263
 264   WLAN_CONNECTION_ATTRIBUTES* conn_info_ptr;
 265   DWORD conn_info_size = 0;
 266   WLAN_OPCODE_VALUE_TYPE op_code;
 267   result = wlanapi.query_interface_func(
 268       client, &info->InterfaceGuid, wlan_intf_opcode_current_connection, NULL,
 269       &conn_info_size, reinterpret_cast<VOID**>(&conn_info_ptr), &op_code);
 270   if (result != ERROR_SUCCESS)
 271     return WIFI_PHY_LAYER_PROTOCOL_UNKNOWN;
 272   scoped_ptr<WLAN_CONNECTION_ATTRIBUTES, WlanApiDeleter> conn_info(
 273       conn_info_ptr);
 274
 275   switch (conn_info->wlanAssociationAttributes.dot11PhyType) {
 276     case dot11_phy_type_fhss:
 277       return WIFI_PHY_LAYER_PROTOCOL_ANCIENT;
 278     case dot11_phy_type_dsss:
 279       return WIFI_PHY_LAYER_PROTOCOL_B;
 280     case dot11_phy_type_irbaseband:
 281       return WIFI_PHY_LAYER_PROTOCOL_ANCIENT;
 282     case dot11_phy_type_ofdm:
 283       return WIFI_PHY_LAYER_PROTOCOL_A;
 284     case dot11_phy_type_hrdsss:
 285       return WIFI_PHY_LAYER_PROTOCOL_B;
 286     case dot11_phy_type_erp:
 287       return WIFI_PHY_LAYER_PROTOCOL_G;
 288     case dot11_phy_type_ht:
 289       return WIFI_PHY_LAYER_PROTOCOL_N;
 290     default:
 291       return WIFI_PHY_LAYER_PROTOCOL_UNKNOWN;
 292   }
 293 }
 294
 295 }  // namespace net