wpa_supplicant/ctrl_iface_unix.c

   1 /*
   2  * WPA Supplicant / UNIX domain socket -based control interface
   3  * Copyright (c) 2004-2013, Jouni Malinen <j@w1.fi>
   4  *
   5  * This software may be distributed under the terms of the BSD license.
   6  * See README for more details.
   7  */
   8
   9 #include "includes.h"
  10 #include <sys/un.h>
  11 #include <sys/stat.h>
  12 #include <grp.h>
  13 #include <stddef.h>
  14 #include <unistd.h>
  15 #include <fcntl.h>
  16 #ifdef ANDROID
  17 #include <cutils/sockets.h>
  18 #endif /* ANDROID */
  19
  20 #include "utils/common.h"
  21 #include "utils/eloop.h"
  22 #include "utils/list.h"
  23 #include "eapol_supp/eapol_supp_sm.h"
  24 #include "config.h"
  25 #include "wpa_supplicant_i.h"
  26 #include "ctrl_iface.h"
  27
  28 /* Per-interface ctrl_iface */
  29
  30 /**
  31  * struct wpa_ctrl_dst - Internal data structure of control interface monitors
  32  *
  33  * This structure is used to store information about registered control
  34  * interface monitors into struct wpa_supplicant. This data is private to
  35  * ctrl_iface_unix.c and should not be touched directly from other files.
  36  */
  37 struct wpa_ctrl_dst {
  38         struct dl_list list;
  39         struct sockaddr_un addr;
  40         socklen_t addrlen;
  41         int debug_level;
  42         int errors;
  43 };
  44
  45
  46 struct ctrl_iface_priv {
  47         struct wpa_supplicant *wpa_s;
  48         int sock;
  49         struct dl_list ctrl_dst;
  50 };
  51
  52
  53 struct ctrl_iface_global_priv {
  54         struct wpa_global *global;
  55         int sock;
  56         struct dl_list ctrl_dst;
  57 };
  58
  59
  60 static void wpa_supplicant_ctrl_iface_send(const char *ifname, int sock,
  61                                            struct dl_list *ctrl_dst,
  62                                            int level, const char *buf,
  63                                            size_t len);
  64
  65
  66 static int wpa_supplicant_ctrl_iface_attach(struct dl_list *ctrl_dst,
  67                                             struct sockaddr_un *from,
  68                                             socklen_t fromlen)
  69 {
  70         struct wpa_ctrl_dst *dst;
  71
  72         dst = os_zalloc(sizeof(*dst));
  73         if (dst == NULL)
  74                 return -1;
  75         os_memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
  76         dst->addrlen = fromlen;
  77         dst->debug_level = MSG_INFO;
  78         dl_list_add(ctrl_dst, &dst->list);
  79         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor attached",
  80                     (u8 *) from->sun_path,
  81                     fromlen - offsetof(struct sockaddr_un, sun_path));
  82         return 0;
  83 }
  84
  85
  86 static int wpa_supplicant_ctrl_iface_detach(struct dl_list *ctrl_dst,
  87                                             struct sockaddr_un *from,
  88                                             socklen_t fromlen)
  89 {
  90         struct wpa_ctrl_dst *dst;
  91
  92         dl_list_for_each(dst, ctrl_dst, struct wpa_ctrl_dst, list) {
  93                 if (fromlen == dst->addrlen &&
  94                     os_memcmp(from->sun_path, dst->addr.sun_path,
  95                               fromlen - offsetof(struct sockaddr_un, sun_path))
  96                     == 0) {
  97                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor detached",
  98                                     (u8 *) from->sun_path,
  99                                     fromlen -
 100                                     offsetof(struct sockaddr_un, sun_path));
 101                         dl_list_del(&dst->list);
 102                         os_free(dst);
 103                         return 0;
 104                 }
 105         }
 106         return -1;
 107 }
 108
 109
 110 static int wpa_supplicant_ctrl_iface_level(struct ctrl_iface_priv *priv,
 111                                            struct sockaddr_un *from,
 112                                            socklen_t fromlen,
 113                                            char *level)
 114 {
 115         struct wpa_ctrl_dst *dst;
 116
 117         wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", level);
 118
 119         dl_list_for_each(dst, &priv->ctrl_dst, struct wpa_ctrl_dst, list) {
 120                 if (fromlen == dst->addrlen &&
 121                     os_memcmp(from->sun_path, dst->addr.sun_path,
 122                               fromlen - offsetof(struct sockaddr_un, sun_path))
 123                     == 0) {
 124                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE changed monitor "
 125                                     "level", (u8 *) from->sun_path,
 126                                     fromlen -
 127                                     offsetof(struct sockaddr_un, sun_path));
 128                         dst->debug_level = atoi(level);
 129                         return 0;
 130                 }
 131         }
 132
 133         return -1;
 134 }
 135
 136
 137 static void wpa_supplicant_ctrl_iface_receive(int sock, void *eloop_ctx,
 138                                               void *sock_ctx)
 139 {
 140         struct wpa_supplicant *wpa_s = eloop_ctx;
 141         struct ctrl_iface_priv *priv = sock_ctx;
 142         char buf[4096];
 143         int res;
 144         struct sockaddr_un from;
 145         socklen_t fromlen = sizeof(from);
 146         char *reply = NULL;
 147         size_t reply_len = 0;
 148         int new_attached = 0;
 149
 150         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 151                        (struct sockaddr *) &from, &fromlen);
 152         if (res < 0) {
 153                 wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 154                            strerror(errno));
 155                 return;
 156         }
 157         buf[res] = '\0';
 158
 159         if (os_strcmp(buf, "ATTACH") == 0) {
 160                 if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
 161                                                      fromlen))
 162                         reply_len = 1;
 163                 else {
 164                         new_attached = 1;
 165                         reply_len = 2;
 166                 }
 167         } else if (os_strcmp(buf, "DETACH") == 0) {
 168                 if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
 169                                                      fromlen))
 170                         reply_len = 1;
 171                 else
 172                         reply_len = 2;
 173         } else if (os_strncmp(buf, "LEVEL ", 6) == 0) {
 174                 if (wpa_supplicant_ctrl_iface_level(priv, &from, fromlen,
 175                                                     buf + 6))
 176                         reply_len = 1;
 177                 else
 178                         reply_len = 2;
 179         } else {
 180                 reply = wpa_supplicant_ctrl_iface_process(wpa_s, buf,
 181                                                           &reply_len);
 182         }
 183
 184         if (reply) {
 185                 sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 186                        fromlen);
 187                 os_free(reply);
 188         } else if (reply_len == 1) {
 189                 sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
 190                        fromlen);
 191         } else if (reply_len == 2) {
 192                 sendto(sock, "OK\n", 3, 0, (struct sockaddr *) &from,
 193                        fromlen);
 194         }
 195
 196         if (new_attached)
 197                 eapol_sm_notify_ctrl_attached(wpa_s->eapol);
 198 }
 199
 200
 201 static char * wpa_supplicant_ctrl_iface_path(struct wpa_supplicant *wpa_s)
 202 {
 203         char *buf;
 204         size_t len;
 205         char *pbuf, *dir = NULL, *gid_str = NULL;
 206         int res;
 207
 208         if (wpa_s->conf->ctrl_interface == NULL)
 209                 return NULL;
 210
 211         pbuf = os_strdup(wpa_s->conf->ctrl_interface);
 212         if (pbuf == NULL)
 213                 return NULL;
 214         if (os_strncmp(pbuf, "DIR=", 4) == 0) {
 215                 dir = pbuf + 4;
 216                 gid_str = os_strstr(dir, " GROUP=");
 217                 if (gid_str) {
 218                         *gid_str = '\0';
 219                         gid_str += 7;
 220                 }
 221         } else
 222                 dir = pbuf;
 223
 224         len = os_strlen(dir) + os_strlen(wpa_s->ifname) + 2;
 225         buf = os_malloc(len);
 226         if (buf == NULL) {
 227                 os_free(pbuf);
 228                 return NULL;
 229         }
 230
 231         res = os_snprintf(buf, len, "%s/%s", dir, wpa_s->ifname);
 232         if (res < 0 || (size_t) res >= len) {
 233                 os_free(pbuf);
 234                 os_free(buf);
 235                 return NULL;
 236         }
 237 #ifdef __CYGWIN__
 238         {
 239                 /* Windows/WinPcap uses interface names that are not suitable
 240                  * as a file name - convert invalid chars to underscores */
 241                 char *pos = buf;
 242                 while (*pos) {
 243                         if (*pos == '\\')
 244                                 *pos = '_';
 245                         pos++;
 246                 }
 247         }
 248 #endif /* __CYGWIN__ */
 249         os_free(pbuf);
 250         return buf;
 251 }
 252
 253
 254 static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level, int global,
 255                                              const char *txt, size_t len)
 256 {
 257         struct wpa_supplicant *wpa_s = ctx;
 258
 259         if (wpa_s == NULL)
 260                 return;
 261
 262         if (global != 2 && wpa_s->global->ctrl_iface) {
 263                 struct ctrl_iface_global_priv *priv = wpa_s->global->ctrl_iface;
 264                 if (!dl_list_empty(&priv->ctrl_dst)) {
 265                         wpa_supplicant_ctrl_iface_send(global ? NULL :
 266                                                        wpa_s->ifname,
 267                                                        priv->sock,
 268                                                        &priv->ctrl_dst,
 269                                                        level, txt, len);
 270                 }
 271         }
 272
 273         if (wpa_s->ctrl_iface == NULL)
 274                 return;
 275         wpa_supplicant_ctrl_iface_send(NULL, wpa_s->ctrl_iface->sock,
 276                                        &wpa_s->ctrl_iface->ctrl_dst,
 277                                        level, txt, len);
 278 }
 279
 280
 281 struct ctrl_iface_priv *
 282 wpa_supplicant_ctrl_iface_init(struct wpa_supplicant *wpa_s)
 283 {
 284         struct ctrl_iface_priv *priv;
 285         struct sockaddr_un addr;
 286         char *fname = NULL;
 287         gid_t gid = 0;
 288         int gid_set = 0;
 289         char *buf, *dir = NULL, *gid_str = NULL;
 290         struct group *grp;
 291         char *endp;
 292         int flags;
 293
 294         priv = os_zalloc(sizeof(*priv));
 295         if (priv == NULL)
 296                 return NULL;
 297         dl_list_init(&priv->ctrl_dst);
 298         priv->wpa_s = wpa_s;
 299         priv->sock = -1;
 300
 301         if (wpa_s->conf->ctrl_interface == NULL)
 302                 return priv;
 303
 304         buf = os_strdup(wpa_s->conf->ctrl_interface);
 305         if (buf == NULL)
 306                 goto fail;
 307 #ifdef ANDROID
 308         os_snprintf(addr.sun_path, sizeof(addr.sun_path), "wpa_%s",
 309                     wpa_s->conf->ctrl_interface);
 310         priv->sock = android_get_control_socket(addr.sun_path);
 311         if (priv->sock >= 0)
 312                 goto havesock;
 313 #endif /* ANDROID */
 314         if (os_strncmp(buf, "DIR=", 4) == 0) {
 315                 dir = buf + 4;
 316                 gid_str = os_strstr(dir, " GROUP=");
 317                 if (gid_str) {
 318                         *gid_str = '\0';
 319                         gid_str += 7;
 320                 }
 321         } else {
 322                 dir = buf;
 323                 gid_str = wpa_s->conf->ctrl_interface_group;
 324         }
 325
 326         if (mkdir(dir, S_IRWXU | S_IRWXG) < 0) {
 327                 if (errno == EEXIST) {
 328                         wpa_printf(MSG_DEBUG, "Using existing control "
 329                                    "interface directory.");
 330                 } else {
 331                         wpa_printf(MSG_ERROR, "mkdir[ctrl_interface=%s]: %s",
 332                                    dir, strerror(errno));
 333                         goto fail;
 334                 }
 335         }
 336
 337 #ifdef ANDROID
 338         /*
 339          * wpa_supplicant is started from /init.*.rc on Android and that seems
 340          * to be using umask 0077 which would leave the control interface
 341          * directory without group access. This breaks things since Wi-Fi
 342          * framework assumes that this directory can be accessed by other
 343          * applications in the wifi group. Fix this by adding group access even
 344          * if umask value would prevent this.
 345          */
 346         if (chmod(dir, S_IRWXU | S_IRWXG) < 0) {
 347                 wpa_printf(MSG_ERROR, "CTRL: Could not chmod directory: %s",
 348                            strerror(errno));
 349                 /* Try to continue anyway */
 350         }
 351 #endif /* ANDROID */
 352
 353         if (gid_str) {
 354                 grp = getgrnam(gid_str);
 355                 if (grp) {
 356                         gid = grp->gr_gid;
 357                         gid_set = 1;
 358                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 359                                    " (from group name '%s')",
 360                                    (int) gid, gid_str);
 361                 } else {
 362                         /* Group name not found - try to parse this as gid */
 363                         gid = strtol(gid_str, &endp, 10);
 364                         if (*gid_str == '\0' || *endp != '\0') {
 365                                 wpa_printf(MSG_ERROR, "CTRL: Invalid group "
 366                                            "'%s'", gid_str);
 367                                 goto fail;
 368                         }
 369                         gid_set = 1;
 370                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 371                                    (int) gid);
 372                 }
 373         }
 374
 375         if (gid_set && chown(dir, -1, gid) < 0) {
 376                 wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
 377                            dir, (int) gid, strerror(errno));
 378                 goto fail;
 379         }
 380
 381         /* Make sure the group can enter and read the directory */
 382         if (gid_set &&
 383             chmod(dir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP) < 0) {
 384                 wpa_printf(MSG_ERROR, "CTRL: chmod[ctrl_interface]: %s",
 385                            strerror(errno));
 386                 goto fail;
 387         }
 388
 389         if (os_strlen(dir) + 1 + os_strlen(wpa_s->ifname) >=
 390             sizeof(addr.sun_path)) {
 391                 wpa_printf(MSG_ERROR, "ctrl_iface path limit exceeded");
 392                 goto fail;
 393         }
 394
 395         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 396         if (priv->sock < 0) {
 397                 wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
 398                 goto fail;
 399         }
 400
 401         os_memset(&addr, 0, sizeof(addr));
 402 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 403         addr.sun_len = sizeof(addr);
 404 #endif /* __FreeBSD__ */
 405         addr.sun_family = AF_UNIX;
 406         fname = wpa_supplicant_ctrl_iface_path(wpa_s);
 407         if (fname == NULL)
 408                 goto fail;
 409         os_strlcpy(addr.sun_path, fname, sizeof(addr.sun_path));
 410         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 411                 wpa_printf(MSG_DEBUG, "ctrl_iface bind(PF_UNIX) failed: %s",
 412                            strerror(errno));
 413                 if (connect(priv->sock, (struct sockaddr *) &addr,
 414                             sizeof(addr)) < 0) {
 415                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 416                                    " allow connections - assuming it was left"
 417                                    "over from forced program termination");
 418                         if (unlink(fname) < 0) {
 419                                 wpa_printf(MSG_ERROR,
 420                                            "Could not unlink existing ctrl_iface socket '%s': %s",
 421                                            fname, strerror(errno));
 422                                 goto fail;
 423                         }
 424                         if (bind(priv->sock, (struct sockaddr *) &addr,
 425                                  sizeof(addr)) < 0) {
 426                                 wpa_printf(MSG_ERROR, "supp-ctrl-iface-init: bind(PF_UNIX): %s",
 427                                            strerror(errno));
 428                                 goto fail;
 429                         }
 430                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 431                                    "ctrl_iface socket '%s'", fname);
 432                 } else {
 433                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 434                                    "be in use - cannot override it");
 435                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 436                                    "not used anymore", fname);
 437                         os_free(fname);
 438                         fname = NULL;
 439                         goto fail;
 440                 }
 441         }
 442
 443         if (gid_set && chown(fname, -1, gid) < 0) {
 444                 wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
 445                            fname, (int) gid, strerror(errno));
 446                 goto fail;
 447         }
 448
 449         if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
 450                 wpa_printf(MSG_ERROR, "chmod[ctrl_interface=%s]: %s",
 451                            fname, strerror(errno));
 452                 goto fail;
 453         }
 454         os_free(fname);
 455
 456 #ifdef ANDROID
 457 havesock:
 458 #endif /* ANDROID */
 459
 460         /*
 461          * Make socket non-blocking so that we don't hang forever if
 462          * target dies unexpectedly.
 463          */
 464         flags = fcntl(priv->sock, F_GETFL);
 465         if (flags >= 0) {
 466                 flags |= O_NONBLOCK;
 467                 if (fcntl(priv->sock, F_SETFL, flags) < 0) {
 468                         wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
 469                                    strerror(errno));
 470                         /* Not fatal, continue on.*/
 471                 }
 472         }
 473
 474         eloop_register_read_sock(priv->sock, wpa_supplicant_ctrl_iface_receive,
 475                                  wpa_s, priv);
 476         wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
 477
 478         os_free(buf);
 479         return priv;
 480
 481 fail:
 482         if (priv->sock >= 0)
 483                 close(priv->sock);
 484         os_free(priv);
 485         if (fname) {
 486                 unlink(fname);
 487                 os_free(fname);
 488         }
 489         os_free(buf);
 490         return NULL;
 491 }
 492
 493
 494 void wpa_supplicant_ctrl_iface_deinit(struct ctrl_iface_priv *priv)
 495 {
 496         struct wpa_ctrl_dst *dst, *prev;
 497
 498         if (priv->sock > -1) {
 499                 char *fname;
 500                 char *buf, *dir = NULL, *gid_str = NULL;
 501                 eloop_unregister_read_sock(priv->sock);
 502                 if (!dl_list_empty(&priv->ctrl_dst)) {
 503                         /*
 504                          * Wait before closing the control socket if
 505                          * there are any attached monitors in order to allow
 506                          * them to receive any pending messages.
 507                          */
 508                         wpa_printf(MSG_DEBUG, "CTRL_IFACE wait for attached "
 509                                    "monitors to receive messages");
 510                         os_sleep(0, 100000);
 511                 }
 512                 close(priv->sock);
 513                 priv->sock = -1;
 514                 fname = wpa_supplicant_ctrl_iface_path(priv->wpa_s);
 515                 if (fname) {
 516                         unlink(fname);
 517                         os_free(fname);
 518                 }
 519
 520                 buf = os_strdup(priv->wpa_s->conf->ctrl_interface);
 521                 if (buf == NULL)
 522                         goto free_dst;
 523                 if (os_strncmp(buf, "DIR=", 4) == 0) {
 524                         dir = buf + 4;
 525                         gid_str = os_strstr(dir, " GROUP=");
 526                         if (gid_str) {
 527                                 *gid_str = '\0';
 528                                 gid_str += 7;
 529                         }
 530                 } else
 531                         dir = buf;
 532
 533                 if (rmdir(dir) < 0) {
 534                         if (errno == ENOTEMPTY) {
 535                                 wpa_printf(MSG_DEBUG, "Control interface "
 536                                            "directory not empty - leaving it "
 537                                            "behind");
 538                         } else {
 539                                 wpa_printf(MSG_ERROR,
 540                                            "rmdir[ctrl_interface=%s]: %s",
 541                                            dir, strerror(errno));
 542                         }
 543                 }
 544                 os_free(buf);
 545         }
 546
 547 free_dst:
 548         dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
 549                               list)
 550                 os_free(dst);
 551         os_free(priv);
 552 }
 553
 554
 555 /**
 556  * wpa_supplicant_ctrl_iface_send - Send a control interface packet to monitors
 557  * @ifname: Interface name for global control socket or %NULL
 558  * @sock: Local socket fd
 559  * @ctrl_dst: List of attached listeners
 560  * @level: Priority level of the message
 561  * @buf: Message data
 562  * @len: Message length
 563  *
 564  * Send a packet to all monitor programs attached to the control interface.
 565  */
 566 static void wpa_supplicant_ctrl_iface_send(const char *ifname, int sock,
 567                                            struct dl_list *ctrl_dst,
 568                                            int level, const char *buf,
 569                                            size_t len)
 570 {
 571         struct wpa_ctrl_dst *dst, *next;
 572         char levelstr[10];
 573         int idx, res;
 574         struct msghdr msg;
 575         struct iovec io[5];
 576
 577         if (sock < 0 || dl_list_empty(ctrl_dst))
 578                 return;
 579
 580         res = os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);
 581         if (res < 0 || (size_t) res >= sizeof(levelstr))
 582                 return;
 583         idx = 0;
 584         if (ifname) {
 585                 io[idx].iov_base = "IFNAME=";
 586                 io[idx].iov_len = 7;
 587                 idx++;
 588                 io[idx].iov_base = (char *) ifname;
 589                 io[idx].iov_len = os_strlen(ifname);
 590                 idx++;
 591                 io[idx].iov_base = " ";
 592                 io[idx].iov_len = 1;
 593                 idx++;
 594         }
 595         io[idx].iov_base = levelstr;
 596         io[idx].iov_len = os_strlen(levelstr);
 597         idx++;
 598         io[idx].iov_base = (char *) buf;
 599         io[idx].iov_len = len;
 600         idx++;
 601         os_memset(&msg, 0, sizeof(msg));
 602         msg.msg_iov = io;
 603         msg.msg_iovlen = idx;
 604
 605         idx = 0;
 606         dl_list_for_each_safe(dst, next, ctrl_dst, struct wpa_ctrl_dst, list) {
 607                 if (level >= dst->debug_level) {
 608                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor send",
 609                                     (u8 *) dst->addr.sun_path, dst->addrlen -
 610                                     offsetof(struct sockaddr_un, sun_path));
 611                         msg.msg_name = (void *) &dst->addr;
 612                         msg.msg_namelen = dst->addrlen;
 613                         if (sendmsg(sock, &msg, MSG_DONTWAIT) < 0) {
 614                                 int _errno = errno;
 615                                 wpa_printf(MSG_INFO, "CTRL_IFACE monitor[%d]: "
 616                                            "%d - %s",
 617                                            idx, errno, strerror(errno));
 618                                 dst->errors++;
 619                                 if (dst->errors > 1000 ||
 620                                     (_errno != ENOBUFS && dst->errors > 10) ||
 621                                     _errno == ENOENT) {
 622                                         wpa_supplicant_ctrl_iface_detach(
 623                                                 ctrl_dst, &dst->addr,
 624                                                 dst->addrlen);
 625                                 }
 626                         } else
 627                                 dst->errors = 0;
 628                 }
 629                 idx++;
 630         }
 631 }
 632
 633
 634 void wpa_supplicant_ctrl_iface_wait(struct ctrl_iface_priv *priv)
 635 {
 636         char buf[256];
 637         int res;
 638         struct sockaddr_un from;
 639         socklen_t fromlen = sizeof(from);
 640
 641         for (;;) {
 642                 wpa_printf(MSG_DEBUG, "CTRL_IFACE - %s - wait for monitor to "
 643                            "attach", priv->wpa_s->ifname);
 644                 eloop_wait_for_read_sock(priv->sock);
 645
 646                 res = recvfrom(priv->sock, buf, sizeof(buf) - 1, 0,
 647                                (struct sockaddr *) &from, &fromlen);
 648                 if (res < 0) {
 649                         wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 650                                    strerror(errno));
 651                         continue;
 652                 }
 653                 buf[res] = '\0';
 654
 655                 if (os_strcmp(buf, "ATTACH") == 0) {
 656                         /* handle ATTACH signal of first monitor interface */
 657                         if (!wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst,
 658                                                               &from, fromlen)) {
 659                                 sendto(priv->sock, "OK\n", 3, 0,
 660                                        (struct sockaddr *) &from, fromlen);
 661                                 /* OK to continue */
 662                                 return;
 663                         } else {
 664                                 sendto(priv->sock, "FAIL\n", 5, 0,
 665                                        (struct sockaddr *) &from, fromlen);
 666                         }
 667                 } else {
 668                         /* return FAIL for all other signals */
 669                         sendto(priv->sock, "FAIL\n", 5, 0,
 670                                (struct sockaddr *) &from, fromlen);
 671                 }
 672         }
 673 }
 674
 675
 676 /* Global ctrl_iface */
 677
 678 static void wpa_supplicant_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 679                                                      void *sock_ctx)
 680 {
 681         struct wpa_global *global = eloop_ctx;
 682         struct ctrl_iface_global_priv *priv = sock_ctx;
 683         char buf[256];
 684         int res;
 685         struct sockaddr_un from;
 686         socklen_t fromlen = sizeof(from);
 687         char *reply = NULL;
 688         size_t reply_len;
 689
 690         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 691                        (struct sockaddr *) &from, &fromlen);
 692         if (res < 0) {
 693                 wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 694                            strerror(errno));
 695                 return;
 696         }
 697         buf[res] = '\0';
 698
 699         if (os_strcmp(buf, "ATTACH") == 0) {
 700                 if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
 701                                                      fromlen))
 702                         reply_len = 1;
 703                 else
 704                         reply_len = 2;
 705         } else if (os_strcmp(buf, "DETACH") == 0) {
 706                 if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
 707                                                      fromlen))
 708                         reply_len = 1;
 709                 else
 710                         reply_len = 2;
 711         } else {
 712                 reply = wpa_supplicant_global_ctrl_iface_process(global, buf,
 713                                                                  &reply_len);
 714         }
 715
 716         if (reply) {
 717                 sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 718                        fromlen);
 719                 os_free(reply);
 720         } else if (reply_len == 1) {
 721                 sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
 722                        fromlen);
 723         } else if (reply_len == 2) {
 724                 sendto(sock, "OK\n", 3, 0, (struct sockaddr *) &from, fromlen);
 725         }
 726 }
 727
 728
 729 struct ctrl_iface_global_priv *
 730 wpa_supplicant_global_ctrl_iface_init(struct wpa_global *global)
 731 {
 732         struct ctrl_iface_global_priv *priv;
 733         struct sockaddr_un addr;
 734         const char *ctrl = global->params.ctrl_interface;
 735         int flags;
 736
 737         priv = os_zalloc(sizeof(*priv));
 738         if (priv == NULL)
 739                 return NULL;
 740         dl_list_init(&priv->ctrl_dst);
 741         priv->global = global;
 742         priv->sock = -1;
 743
 744         if (ctrl == NULL)
 745                 return priv;
 746
 747         wpa_printf(MSG_DEBUG, "Global control interface '%s'", ctrl);
 748
 749 #ifdef ANDROID
 750         if (os_strncmp(ctrl, "@android:", 9) == 0) {
 751                 priv->sock = android_get_control_socket(ctrl + 9);
 752                 if (priv->sock < 0) {
 753                         wpa_printf(MSG_ERROR, "Failed to open Android control "
 754                                    "socket '%s'", ctrl + 9);
 755                         goto fail;
 756                 }
 757                 wpa_printf(MSG_DEBUG, "Using Android control socket '%s'",
 758                            ctrl + 9);
 759                 goto havesock;
 760         }
 761
 762         if (os_strncmp(ctrl, "@abstract:", 10) != 0) {
 763                 /*
 764                  * Backwards compatibility - try to open an Android control
 765                  * socket and if that fails, assume this was a UNIX domain
 766                  * socket instead.
 767                  */
 768                 priv->sock = android_get_control_socket(ctrl);
 769                 if (priv->sock >= 0) {
 770                         wpa_printf(MSG_DEBUG,
 771                                    "Using Android control socket '%s'",
 772                                    ctrl);
 773                         goto havesock;
 774                 }
 775         }
 776 #endif /* ANDROID */
 777
 778         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 779         if (priv->sock < 0) {
 780                 wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
 781                 goto fail;
 782         }
 783
 784         os_memset(&addr, 0, sizeof(addr));
 785 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 786         addr.sun_len = sizeof(addr);
 787 #endif /* __FreeBSD__ */
 788         addr.sun_family = AF_UNIX;
 789
 790         if (os_strncmp(ctrl, "@abstract:", 10) == 0) {
 791                 addr.sun_path[0] = '\0';
 792                 os_strlcpy(addr.sun_path + 1, ctrl + 10,
 793                            sizeof(addr.sun_path) - 1);
 794                 if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) <
 795                     0) {
 796                         wpa_printf(MSG_ERROR, "supp-global-ctrl-iface-init: "
 797                                    "bind(PF_UNIX;%s) failed: %s",
 798                                    ctrl, strerror(errno));
 799                         goto fail;
 800                 }
 801                 wpa_printf(MSG_DEBUG, "Using Abstract control socket '%s'",
 802                            ctrl + 10);
 803                 goto havesock;
 804         }
 805
 806         os_strlcpy(addr.sun_path, ctrl, sizeof(addr.sun_path));
 807         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 808                 wpa_printf(MSG_INFO, "supp-global-ctrl-iface-init(%s) (will try fixup): bind(PF_UNIX): %s",
 809                            ctrl, strerror(errno));
 810                 if (connect(priv->sock, (struct sockaddr *) &addr,
 811                             sizeof(addr)) < 0) {
 812                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 813                                    " allow connections - assuming it was left"
 814                                    "over from forced program termination");
 815                         if (unlink(ctrl) < 0) {
 816                                 wpa_printf(MSG_ERROR,
 817                                            "Could not unlink existing ctrl_iface socket '%s': %s",
 818                                            ctrl, strerror(errno));
 819                                 goto fail;
 820                         }
 821                         if (bind(priv->sock, (struct sockaddr *) &addr,
 822                                  sizeof(addr)) < 0) {
 823                                 wpa_printf(MSG_ERROR, "supp-glb-iface-init: bind(PF_UNIX;%s): %s",
 824                                            ctrl, strerror(errno));
 825                                 goto fail;
 826                         }
 827                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 828                                    "ctrl_iface socket '%s'",
 829                                    ctrl);
 830                 } else {
 831                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 832                                    "be in use - cannot override it");
 833                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 834                                    "not used anymore",
 835                                    ctrl);
 836                         goto fail;
 837                 }
 838         }
 839
 840         wpa_printf(MSG_DEBUG, "Using UNIX control socket '%s'", ctrl);
 841
 842         if (global->params.ctrl_interface_group) {
 843                 char *gid_str = global->params.ctrl_interface_group;
 844                 gid_t gid = 0;
 845                 struct group *grp;
 846                 char *endp;
 847
 848                 grp = getgrnam(gid_str);
 849                 if (grp) {
 850                         gid = grp->gr_gid;
 851                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 852                                    " (from group name '%s')",
 853                                    (int) gid, gid_str);
 854                 } else {
 855                         /* Group name not found - try to parse this as gid */
 856                         gid = strtol(gid_str, &endp, 10);
 857                         if (*gid_str == '\0' || *endp != '\0') {
 858                                 wpa_printf(MSG_ERROR, "CTRL: Invalid group "
 859                                            "'%s'", gid_str);
 860                                 goto fail;
 861                         }
 862                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 863                                    (int) gid);
 864                 }
 865                 if (chown(ctrl, -1, gid) < 0) {
 866                         wpa_printf(MSG_ERROR,
 867                                    "chown[global_ctrl_interface=%s,gid=%d]: %s",
 868                                    ctrl, (int) gid, strerror(errno));
 869                         goto fail;
 870                 }
 871
 872                 if (chmod(ctrl, S_IRWXU | S_IRWXG) < 0) {
 873                         wpa_printf(MSG_ERROR,
 874                                    "chmod[global_ctrl_interface=%s]: %s",
 875                                    ctrl, strerror(errno));
 876                         goto fail;
 877                 }
 878         } else {
 879                 chmod(ctrl, S_IRWXU);
 880         }
 881
 882 havesock:
 883
 884         /*
 885          * Make socket non-blocking so that we don't hang forever if
 886          * target dies unexpectedly.
 887          */
 888         flags = fcntl(priv->sock, F_GETFL);
 889         if (flags >= 0) {
 890                 flags |= O_NONBLOCK;
 891                 if (fcntl(priv->sock, F_SETFL, flags) < 0) {
 892                         wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
 893                                    strerror(errno));
 894                         /* Not fatal, continue on.*/
 895                 }
 896         }
 897
 898         eloop_register_read_sock(priv->sock,
 899                                  wpa_supplicant_global_ctrl_iface_receive,
 900                                  global, priv);
 901
 902         return priv;
 903
 904 fail:
 905         if (priv->sock >= 0)
 906                 close(priv->sock);
 907         os_free(priv);
 908         return NULL;
 909 }
 910
 911
 912 void
 913 wpa_supplicant_global_ctrl_iface_deinit(struct ctrl_iface_global_priv *priv)
 914 {
 915         struct wpa_ctrl_dst *dst, *prev;
 916
 917         if (priv->sock >= 0) {
 918                 eloop_unregister_read_sock(priv->sock);
 919                 close(priv->sock);
 920         }
 921         if (priv->global->params.ctrl_interface)
 922                 unlink(priv->global->params.ctrl_interface);
 923         dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
 924                               list)
 925                 os_free(dst);
 926         os_free(priv);
 927 }