contrib/wpa_supplicant/wpa_ctrl.c

   1 /*
   2  * wpa_supplicant/hostapd control interface library
   3  * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  *
  14  * $FreeBSD$
  15  */
  16
  17 #include "includes.h"
  18
  19 #ifdef CONFIG_CTRL_IFACE
  20
  21 #ifdef CONFIG_CTRL_IFACE_UNIX
  22 #include <sys/un.h>
  23 #endif /* CONFIG_CTRL_IFACE_UNIX */
  24
  25 #include "wpa_ctrl.h"
  26 #include "common.h"
  27
  28
  29 #if defined(CONFIG_CTRL_IFACE_UNIX) || defined(CONFIG_CTRL_IFACE_UDP)
  30 #define CTRL_IFACE_SOCKET
  31 #endif /* CONFIG_CTRL_IFACE_UNIX || CONFIG_CTRL_IFACE_UDP */
  32
  33
  34 /**
  35  * struct wpa_ctrl - Internal structure for control interface library
  36  *
  37  * This structure is used by the wpa_supplicant/hostapd control interface
  38  * library to store internal data. Programs using the library should not touch
  39  * this data directly. They can only use the pointer to the data structure as
  40  * an identifier for the control interface connection and use this as one of
  41  * the arguments for most of the control interface library functions.
  42  */
  43 struct wpa_ctrl {
  44 #ifdef CONFIG_CTRL_IFACE_UDP
  45         int s;
  46         struct sockaddr_in local;
  47         struct sockaddr_in dest;
  48         char *cookie;
  49 #endif /* CONFIG_CTRL_IFACE_UDP */
  50 #ifdef CONFIG_CTRL_IFACE_UNIX
  51         int s;
  52         struct sockaddr_un local;
  53         struct sockaddr_un dest;
  54 #endif /* CONFIG_CTRL_IFACE_UNIX */
  55 #ifdef CONFIG_CTRL_IFACE_NAMED_PIPE
  56         HANDLE pipe;
  57 #endif /* CONFIG_CTRL_IFACE_NAMED_PIPE */
  58 };
  59
  60
  61 #ifdef CONFIG_CTRL_IFACE_UNIX
  62
  63 struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path)
  64 {
  65         struct wpa_ctrl *ctrl;
  66         static int counter = 0;
  67
  68         ctrl = os_malloc(sizeof(*ctrl));
  69         if (ctrl == NULL)
  70                 return NULL;
  71         os_memset(ctrl, 0, sizeof(*ctrl));
  72
  73         ctrl->s = socket(PF_UNIX, SOCK_DGRAM, 0);
  74         if (ctrl->s < 0) {
  75                 os_free(ctrl);
  76                 return NULL;
  77         }
  78
  79         ctrl->local.sun_family = AF_UNIX;
  80         os_snprintf(ctrl->local.sun_path, sizeof(ctrl->local.sun_path),
  81                     "/tmp/wpa_ctrl_%d-%d", getpid(), counter++);
  82         if (bind(ctrl->s, (struct sockaddr *) &ctrl->local,
  83                     sizeof(ctrl->local)) < 0) {
  84                 close(ctrl->s);
  85                 os_free(ctrl);
  86                 return NULL;
  87         }
  88
  89         ctrl->dest.sun_family = AF_UNIX;
  90         os_snprintf(ctrl->dest.sun_path, sizeof(ctrl->dest.sun_path), "%s",
  91                     ctrl_path);
  92         if (connect(ctrl->s, (struct sockaddr *) &ctrl->dest,
  93                     sizeof(ctrl->dest)) < 0) {
  94                 close(ctrl->s);
  95                 unlink(ctrl->local.sun_path);
  96                 os_free(ctrl);
  97                 return NULL;
  98         }
  99
 100         return ctrl;
 101 }
 102
 103
 104 void wpa_ctrl_close(struct wpa_ctrl *ctrl)
 105 {
 106         unlink(ctrl->local.sun_path);
 107         close(ctrl->s);
 108         os_free(ctrl);
 109 }
 110
 111 #endif /* CONFIG_CTRL_IFACE_UNIX */
 112
 113
 114 #ifdef CONFIG_CTRL_IFACE_UDP
 115
 116 struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path)
 117 {
 118         struct wpa_ctrl *ctrl;
 119         char buf[128];
 120         size_t len;
 121
 122         ctrl = os_malloc(sizeof(*ctrl));
 123         if (ctrl == NULL)
 124                 return NULL;
 125         os_memset(ctrl, 0, sizeof(*ctrl));
 126
 127         ctrl->s = socket(PF_INET, SOCK_DGRAM, 0);
 128         if (ctrl->s < 0) {
 129                 perror("socket");
 130                 os_free(ctrl);
 131                 return NULL;
 132         }
 133
 134         ctrl->local.sin_family = AF_INET;
 135         ctrl->local.sin_addr.s_addr = htonl((127 << 24) | 1);
 136         if (bind(ctrl->s, (struct sockaddr *) &ctrl->local,
 137                  sizeof(ctrl->local)) < 0) {
 138                 close(ctrl->s);
 139                 os_free(ctrl);
 140                 return NULL;
 141         }
 142
 143         ctrl->dest.sin_family = AF_INET;
 144         ctrl->dest.sin_addr.s_addr = htonl((127 << 24) | 1);
 145         ctrl->dest.sin_port = htons(WPA_CTRL_IFACE_PORT);
 146         if (connect(ctrl->s, (struct sockaddr *) &ctrl->dest,
 147                     sizeof(ctrl->dest)) < 0) {
 148                 perror("connect");
 149                 close(ctrl->s);
 150                 os_free(ctrl);
 151                 return NULL;
 152         }
 153
 154         len = sizeof(buf) - 1;
 155         if (wpa_ctrl_request(ctrl, "GET_COOKIE", 10, buf, &len, NULL) == 0) {
 156                 buf[len] = '\0';
 157                 ctrl->cookie = strdup(buf);
 158         }
 159
 160         return ctrl;
 161 }
 162
 163
 164 void wpa_ctrl_close(struct wpa_ctrl *ctrl)
 165 {
 166         close(ctrl->s);
 167         os_free(ctrl->cookie);
 168         os_free(ctrl);
 169 }
 170
 171 #endif /* CONFIG_CTRL_IFACE_UDP */
 172
 173
 174 #ifdef CTRL_IFACE_SOCKET
 175 int wpa_ctrl_request(struct wpa_ctrl *ctrl, const char *cmd, size_t cmd_len,
 176                      char *reply, size_t *reply_len,
 177                      void (*msg_cb)(char *msg, size_t len))
 178 {
 179         struct timeval tv;
 180         int res;
 181         fd_set rfds;
 182         const char *_cmd;
 183         char *cmd_buf = NULL;
 184         size_t _cmd_len;
 185
 186 #ifdef CONFIG_CTRL_IFACE_UDP
 187         if (ctrl->cookie) {
 188                 char *pos;
 189                 _cmd_len = strlen(ctrl->cookie) + 1 + cmd_len;
 190                 cmd_buf = os_malloc(_cmd_len );
 191                 if (cmd_buf == NULL)
 192                         return -1;
 193                 _cmd = cmd_buf;
 194                 pos = cmd_buf;
 195                 strcpy(pos, ctrl->cookie);
 196                 pos += strlen(ctrl->cookie);
 197                 *pos++ = ' ';
 198                 memcpy(pos, cmd, cmd_len);
 199         } else
 200 #endif /* CONFIG_CTRL_IFACE_UDP */
 201         {
 202                 _cmd = cmd;
 203                 _cmd_len = cmd_len;
 204         }
 205
 206         if (send(ctrl->s, _cmd, _cmd_len, 0) < 0) {
 207                 os_free(cmd_buf);
 208                 return -1;
 209         }
 210         os_free(cmd_buf);
 211
 212         for (;;) {
 213                 tv.tv_sec = 2;
 214                 tv.tv_usec = 0;
 215                 FD_ZERO(&rfds);
 216                 FD_SET(ctrl->s, &rfds);
 217                 res = select(ctrl->s + 1, &rfds, NULL, NULL, &tv);
 218                 if (FD_ISSET(ctrl->s, &rfds)) {
 219                         res = recv(ctrl->s, reply, *reply_len, 0);
 220                         if (res < 0)
 221                                 return res;
 222                         if (res > 0 && reply[0] == '<') {
 223                                 /* This is an unsolicited message from
 224                                  * wpa_supplicant, not the reply to the
 225                                  * request. Use msg_cb to report this to the
 226                                  * caller. */
 227                                 if (msg_cb) {
 228                                         /* Make sure the message is nul
 229                                          * terminated. */
 230                                         if ((size_t) res == *reply_len)
 231                                                 res = (*reply_len) - 1;
 232                                         reply[res] = '\0';
 233                                         msg_cb(reply, res);
 234                                 }
 235                                 continue;
 236                         }
 237                         *reply_len = res;
 238                         break;
 239                 } else {
 240                         return -2;
 241                 }
 242         }
 243         return 0;
 244 }
 245 #endif /* CTRL_IFACE_SOCKET */
 246
 247
 248 static int wpa_ctrl_attach_helper(struct wpa_ctrl *ctrl, int attach)
 249 {
 250         char buf[10];
 251         int ret;
 252         size_t len = 10;
 253
 254         ret = wpa_ctrl_request(ctrl, attach ? "ATTACH" : "DETACH", 6,
 255                                buf, &len, NULL);
 256         if (ret < 0)
 257                 return ret;
 258         if (len == 3 && os_memcmp(buf, "OK\n", 3) == 0)
 259                 return 0;
 260         return -1;
 261 }
 262
 263
 264 int wpa_ctrl_attach(struct wpa_ctrl *ctrl)
 265 {
 266         return wpa_ctrl_attach_helper(ctrl, 1);
 267 }
 268
 269
 270 int wpa_ctrl_detach(struct wpa_ctrl *ctrl)
 271 {
 272         return wpa_ctrl_attach_helper(ctrl, 0);
 273 }
 274
 275
 276 #ifdef CTRL_IFACE_SOCKET
 277
 278 int wpa_ctrl_recv(struct wpa_ctrl *ctrl, char *reply, size_t *reply_len)
 279 {
 280         int res;
 281
 282         res = recv(ctrl->s, reply, *reply_len, 0);
 283         if (res < 0)
 284                 return res;
 285         *reply_len = res;
 286         return 0;
 287 }
 288
 289
 290 int wpa_ctrl_pending(struct wpa_ctrl *ctrl)
 291 {
 292         struct timeval tv;
 293         fd_set rfds;
 294         tv.tv_sec = 0;
 295         tv.tv_usec = 0;
 296         FD_ZERO(&rfds);
 297         FD_SET(ctrl->s, &rfds);
 298         select(ctrl->s + 1, &rfds, NULL, NULL, &tv);
 299         return FD_ISSET(ctrl->s, &rfds);
 300 }
 301
 302
 303 int wpa_ctrl_get_fd(struct wpa_ctrl *ctrl)
 304 {
 305         return ctrl->s;
 306 }
 307
 308 #endif /* CTRL_IFACE_SOCKET */
 309
 310
 311 #ifdef CONFIG_CTRL_IFACE_NAMED_PIPE
 312
 313 #ifndef WPA_SUPPLICANT_NAMED_PIPE
 314 #define WPA_SUPPLICANT_NAMED_PIPE "WpaSupplicant"
 315 #endif
 316 #define NAMED_PIPE_PREFIX TEXT("\\\\.\\pipe\\") TEXT(WPA_SUPPLICANT_NAMED_PIPE)
 317
 318 struct wpa_ctrl * wpa_ctrl_open(const char *ctrl_path)
 319 {
 320         struct wpa_ctrl *ctrl;
 321         DWORD mode;
 322         TCHAR name[256];
 323         int i;
 324
 325         ctrl = os_malloc(sizeof(*ctrl));
 326         if (ctrl == NULL)
 327                 return NULL;
 328         os_memset(ctrl, 0, sizeof(*ctrl));
 329
 330 #ifdef UNICODE
 331         if (ctrl_path == NULL)
 332                 _snwprintf(name, 256, NAMED_PIPE_PREFIX);
 333         else
 334                 _snwprintf(name, 256, NAMED_PIPE_PREFIX TEXT("-%S"),
 335                            ctrl_path);
 336 #else /* UNICODE */
 337         if (ctrl_path == NULL)
 338                 os_snprintf(name, 256, NAMED_PIPE_PREFIX);
 339         else
 340                 os_snprintf(name, 256, NAMED_PIPE_PREFIX "-%s",
 341                             ctrl_path);
 342 #endif /* UNICODE */
 343
 344         for (i = 0; i < 10; i++) {
 345                 ctrl->pipe = CreateFile(name, GENERIC_READ | GENERIC_WRITE, 0,
 346                                         NULL, OPEN_EXISTING, 0, NULL);
 347                 /*
 348                  * Current named pipe server side in wpa_supplicant is
 349                  * re-opening the pipe for new clients only after the previous
 350                  * one is taken into use. This leaves a small window for race
 351                  * conditions when two connections are being opened at almost
 352                  * the same time. Retry if that was the case.
 353                  */
 354                 if (ctrl->pipe != INVALID_HANDLE_VALUE ||
 355                     GetLastError() != ERROR_PIPE_BUSY)
 356                         break;
 357                 WaitNamedPipe(name, 1000);
 358         }
 359         if (ctrl->pipe == INVALID_HANDLE_VALUE) {
 360                 os_free(ctrl);
 361                 return NULL;
 362         }
 363
 364         mode = PIPE_READMODE_MESSAGE;
 365         if (!SetNamedPipeHandleState(ctrl->pipe, &mode, NULL, NULL)) {
 366                 CloseHandle(ctrl->pipe);
 367                 os_free(ctrl);
 368                 return NULL;
 369         }
 370
 371         return ctrl;
 372 }
 373
 374
 375 void wpa_ctrl_close(struct wpa_ctrl *ctrl)
 376 {
 377         CloseHandle(ctrl->pipe);
 378         os_free(ctrl);
 379 }
 380
 381
 382 int wpa_ctrl_request(struct wpa_ctrl *ctrl, const char *cmd, size_t cmd_len,
 383                      char *reply, size_t *reply_len,
 384                      void (*msg_cb)(char *msg, size_t len))
 385 {
 386         DWORD written;
 387         DWORD readlen = *reply_len;
 388
 389         if (!WriteFile(ctrl->pipe, cmd, cmd_len, &written, NULL))
 390                 return -1;
 391
 392         if (!ReadFile(ctrl->pipe, reply, *reply_len, &readlen, NULL))
 393                 return -1;
 394         *reply_len = readlen;
 395
 396         return 0;
 397 }
 398
 399
 400 int wpa_ctrl_recv(struct wpa_ctrl *ctrl, char *reply, size_t *reply_len)
 401 {
 402         DWORD len = *reply_len;
 403         if (!ReadFile(ctrl->pipe, reply, *reply_len, &len, NULL))
 404                 return -1;
 405         *reply_len = len;
 406         return 0;
 407 }
 408
 409
 410 int wpa_ctrl_pending(struct wpa_ctrl *ctrl)
 411 {
 412         DWORD left;
 413
 414         if (!PeekNamedPipe(ctrl->pipe, NULL, 0, NULL, &left, NULL))
 415                 return -1;
 416         return left ? 1 : 0;
 417 }
 418
 419
 420 int wpa_ctrl_get_fd(struct wpa_ctrl *ctrl)
 421 {
 422         return -1;
 423 }
 424
 425 #endif /* CONFIG_CTRL_IFACE_NAMED_PIPE */
 426
 427 #endif /* CONFIG_CTRL_IFACE */