dom/wifi/WifiHotspotUtils.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include "WifiHotspotUtils.h"
   6 #include <dlfcn.h>
   7 #include <errno.h>
   8 #include <string.h>
   9 #include <dirent.h>
  10 #include <stdlib.h>
  11 #include <cutils/properties.h>
  12
  13 #include "prinit.h"
  14 #include "mozilla/Assertions.h"
  15 #include "nsDebug.h"
  16 #include "nsPrintfCString.h"
  17
  18 static void* sWifiHotspotUtilsLib;
  19 static PRCallOnceType sInitWifiHotspotUtilsLib;
  20 // Socket pair used to exit from a blocking read.
  21 static struct wpa_ctrl* ctrl_conn;
  22 static const char *ctrl_iface_dir = "/data/misc/wifi/hostapd";
  23 static char *ctrl_ifname = nullptr;
  24
  25 DEFINE_DLFUNC(wpa_ctrl_open, struct wpa_ctrl*, const char*)
  26 DEFINE_DLFUNC(wpa_ctrl_close, void, struct wpa_ctrl*)
  27 DEFINE_DLFUNC(wpa_ctrl_attach, int32_t, struct wpa_ctrl*)
  28 DEFINE_DLFUNC(wpa_ctrl_detach, int32_t, struct wpa_ctrl*)
  29 DEFINE_DLFUNC(wpa_ctrl_request, int32_t, struct wpa_ctrl*,
  30               const char*, size_t cmd_len, char *reply,
  31               size_t *reply_len, void (*msg_cb)(char *msg, size_t len))
  32
  33
  34 static PRStatus
  35 InitWifiHotspotUtilsLib()
  36 {
  37   sWifiHotspotUtilsLib = dlopen("/system/lib/libwpa_client.so", RTLD_LAZY);
  38   // We might fail to open the hardware lib. That's OK.
  39   return PR_SUCCESS;
  40 }
  41
  42 static void*
  43 GetWifiHotspotLibHandle()
  44 {
  45   PR_CallOnce(&sInitWifiHotspotUtilsLib, InitWifiHotspotUtilsLib);
  46   return sWifiHotspotUtilsLib;
  47 }
  48
  49 struct wpa_ctrl *
  50 WifiHotspotUtils::openConnection(const char *ifname)
  51 {
  52   if (!ifname) {
  53     return nullptr;
  54   }
  55
  56   USE_DLFUNC(wpa_ctrl_open)
  57   ctrl_conn = wpa_ctrl_open(nsPrintfCString("%s/%s", ctrl_iface_dir, ifname).get());
  58   return ctrl_conn;
  59 }
  60
  61 int32_t
  62 WifiHotspotUtils::sendCommand(struct wpa_ctrl *ctrl, const char *cmd,
  63                               char *reply, size_t *reply_len)
  64 {
  65   int32_t ret;
  66
  67   if (!ctrl_conn) {
  68     NS_WARNING(nsPrintfCString("Not connected to hostapd - \"%s\" command dropped.\n", cmd).get());
  69     return -1;
  70   }
  71
  72   USE_DLFUNC(wpa_ctrl_request)
  73   ret = wpa_ctrl_request(ctrl, cmd, strlen(cmd), reply, reply_len, nullptr);
  74   if (ret == -2) {
  75     NS_WARNING(nsPrintfCString("'%s' command timed out.\n", cmd).get());
  76     return -2;
  77   } else if (ret < 0 || strncmp(reply, "FAIL", 4) == 0) {
  78     return -1;
  79   }
  80
  81   // Make the reply printable.
  82   reply[*reply_len] = '\0';
  83   if (strncmp(cmd, "STA-FIRST", 9) == 0 ||
  84       strncmp(cmd, "STA-NEXT", 8) == 0) {
  85     char *pos = reply;
  86
  87     while (*pos && *pos != '\n')
  88       pos++;
  89     *pos = '\0';
  90   }
  91
  92   return 0;
  93 }
  94
  95
  96 // static
  97 void*
  98 WifiHotspotUtils::GetSharedLibrary()
  99 {
 100   void* wpaClientLib = GetWifiHotspotLibHandle();
 101   if (!wpaClientLib) {
 102     NS_WARNING("No /system/lib/libwpa_client.so");
 103   }
 104   return wpaClientLib;
 105 }
 106
 107 int32_t WifiHotspotUtils::do_wifi_connect_to_hostapd()
 108 {
 109   struct dirent *dent;
 110
 111   DIR *dir = opendir(ctrl_iface_dir);
 112   if (dir) {
 113     while ((dent = readdir(dir))) {
 114       if (strcmp(dent->d_name, ".") == 0 ||
 115           strcmp(dent->d_name, "..") == 0) {
 116         continue;
 117       }
 118       ctrl_ifname = strdup(dent->d_name);
 119       break;
 120     }
 121     closedir(dir);
 122   }
 123
 124   ctrl_conn = openConnection(ctrl_ifname);
 125   if (!ctrl_conn) {
 126     NS_WARNING(nsPrintfCString("Unable to open connection to hostapd on \"%s\": %s",
 127                ctrl_ifname, strerror(errno)).get());
 128     return -1;
 129   }
 130
 131   USE_DLFUNC(wpa_ctrl_attach)
 132   if (wpa_ctrl_attach(ctrl_conn) != 0) {
 133     USE_DLFUNC(wpa_ctrl_close)
 134     wpa_ctrl_close(ctrl_conn);
 135     ctrl_conn = nullptr;
 136     return -1;
 137   }
 138
 139   return 0;
 140 }
 141
 142 int32_t WifiHotspotUtils::do_wifi_close_hostapd_connection()
 143 {
 144   if (!ctrl_conn) {
 145     NS_WARNING("Invalid ctrl_conn.");
 146     return -1;
 147   }
 148
 149   USE_DLFUNC(wpa_ctrl_detach)
 150   if (wpa_ctrl_detach(ctrl_conn) < 0) {
 151     NS_WARNING("Failed to detach wpa_ctrl.");
 152   }
 153
 154   USE_DLFUNC(wpa_ctrl_close)
 155   wpa_ctrl_close(ctrl_conn);
 156   ctrl_conn = nullptr;
 157   return 0;
 158 }
 159
 160 int32_t WifiHotspotUtils::do_wifi_hostapd_command(const char *command,
 161                                                   char *reply,
 162                                                   size_t *reply_len)
 163 {
 164   return sendCommand(ctrl_conn, command, reply, reply_len);
 165 }
 166
 167 int32_t WifiHotspotUtils::do_wifi_hostapd_get_stations()
 168 {
 169   char addr[32], cmd[64];
 170   int stations = 0;
 171   size_t addrLen = sizeof(addr);
 172
 173   if (sendCommand(ctrl_conn, "STA-FIRST", addr, &addrLen)) {
 174     return 0;
 175   }
 176   stations++;
 177
 178   sprintf(cmd, "STA-NEXT %s", addr);
 179   while (sendCommand(ctrl_conn, cmd, addr, &addrLen) == 0) {
 180     stations++;
 181     sprintf(cmd, "STA-NEXT %s", addr);
 182   }
 183
 184   return stations;
 185 }