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(struct wpa_supplicant *wpa_s,
  61                                            const char *ifname, int sock,
  62                                            struct dl_list *ctrl_dst,
  63                                            int level, const char *buf,
  64                                            size_t len,
  65                                            struct ctrl_iface_priv *priv,
  66                                            struct ctrl_iface_global_priv *gp);
  67 static int wpas_ctrl_iface_reinit(struct wpa_supplicant *wpa_s,
  68                                   struct ctrl_iface_priv *priv);
  69 static int wpas_ctrl_iface_global_reinit(struct wpa_global *global,
  70                                          struct ctrl_iface_global_priv *priv);
  71
  72
  73 static int wpa_supplicant_ctrl_iface_attach(struct dl_list *ctrl_dst,
  74                                             struct sockaddr_un *from,
  75                                             socklen_t fromlen)
  76 {
  77         struct wpa_ctrl_dst *dst;
  78
  79         dst = os_zalloc(sizeof(*dst));
  80         if (dst == NULL)
  81                 return -1;
  82         os_memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
  83         dst->addrlen = fromlen;
  84         dst->debug_level = MSG_INFO;
  85         dl_list_add(ctrl_dst, &dst->list);
  86         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor attached",
  87                     (u8 *) from->sun_path,
  88                     fromlen - offsetof(struct sockaddr_un, sun_path));
  89         return 0;
  90 }
  91
  92
  93 static int wpa_supplicant_ctrl_iface_detach(struct dl_list *ctrl_dst,
  94                                             struct sockaddr_un *from,
  95                                             socklen_t fromlen)
  96 {
  97         struct wpa_ctrl_dst *dst;
  98
  99         dl_list_for_each(dst, ctrl_dst, struct wpa_ctrl_dst, list) {
 100                 if (fromlen == dst->addrlen &&
 101                     os_memcmp(from->sun_path, dst->addr.sun_path,
 102                               fromlen - offsetof(struct sockaddr_un, sun_path))
 103                     == 0) {
 104                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor detached",
 105                                     (u8 *) from->sun_path,
 106                                     fromlen -
 107                                     offsetof(struct sockaddr_un, sun_path));
 108                         dl_list_del(&dst->list);
 109                         os_free(dst);
 110                         return 0;
 111                 }
 112         }
 113         return -1;
 114 }
 115
 116
 117 static int wpa_supplicant_ctrl_iface_level(struct ctrl_iface_priv *priv,
 118                                            struct sockaddr_un *from,
 119                                            socklen_t fromlen,
 120                                            char *level)
 121 {
 122         struct wpa_ctrl_dst *dst;
 123
 124         wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", level);
 125
 126         dl_list_for_each(dst, &priv->ctrl_dst, struct wpa_ctrl_dst, list) {
 127                 if (fromlen == dst->addrlen &&
 128                     os_memcmp(from->sun_path, dst->addr.sun_path,
 129                               fromlen - offsetof(struct sockaddr_un, sun_path))
 130                     == 0) {
 131                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE changed monitor "
 132                                     "level", (u8 *) from->sun_path,
 133                                     fromlen -
 134                                     offsetof(struct sockaddr_un, sun_path));
 135                         dst->debug_level = atoi(level);
 136                         return 0;
 137                 }
 138         }
 139
 140         return -1;
 141 }
 142
 143
 144 static void wpa_supplicant_ctrl_iface_receive(int sock, void *eloop_ctx,
 145                                               void *sock_ctx)
 146 {
 147         struct wpa_supplicant *wpa_s = eloop_ctx;
 148         struct ctrl_iface_priv *priv = sock_ctx;
 149         char buf[4096];
 150         int res;
 151         struct sockaddr_un from;
 152         socklen_t fromlen = sizeof(from);
 153         char *reply = NULL, *reply_buf = NULL;
 154         size_t reply_len = 0;
 155         int new_attached = 0;
 156
 157         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 158                        (struct sockaddr *) &from, &fromlen);
 159         if (res < 0) {
 160                 wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 161                            strerror(errno));
 162                 return;
 163         }
 164         buf[res] = '\0';
 165
 166         if (os_strcmp(buf, "ATTACH") == 0) {
 167                 if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
 168                                                      fromlen))
 169                         reply_len = 1;
 170                 else {
 171                         new_attached = 1;
 172                         reply_len = 2;
 173                 }
 174         } else if (os_strcmp(buf, "DETACH") == 0) {
 175                 if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
 176                                                      fromlen))
 177                         reply_len = 1;
 178                 else
 179                         reply_len = 2;
 180         } else if (os_strncmp(buf, "LEVEL ", 6) == 0) {
 181                 if (wpa_supplicant_ctrl_iface_level(priv, &from, fromlen,
 182                                                     buf + 6))
 183                         reply_len = 1;
 184                 else
 185                         reply_len = 2;
 186         } else {
 187                 reply_buf = wpa_supplicant_ctrl_iface_process(wpa_s, buf,
 188                                                               &reply_len);
 189                 reply = reply_buf;
 190         }
 191
 192         if (!reply && reply_len == 1) {
 193                 reply = "FAIL\n";
 194                 reply_len = 5;
 195         } else if (!reply && reply_len == 2) {
 196                 reply = "OK\n";
 197                 reply_len = 3;
 198         }
 199
 200         if (reply) {
 201                 if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 202                            fromlen) < 0) {
 203                         int _errno = errno;
 204                         wpa_dbg(wpa_s, MSG_DEBUG,
 205                                 "ctrl_iface sendto failed: %d - %s",
 206                                 _errno, strerror(_errno));
 207                         if (_errno == ENOBUFS || _errno == EAGAIN) {
 208                                 /*
 209                                  * The socket send buffer could be full. This
 210                                  * may happen if client programs are not
 211                                  * receiving their pending messages. Close and
 212                                  * reopen the socket as a workaround to avoid
 213                                  * getting stuck being unable to send any new
 214                                  * responses.
 215                                  */
 216                                 sock = wpas_ctrl_iface_reinit(wpa_s, priv);
 217                                 if (sock < 0) {
 218                                         wpa_dbg(wpa_s, MSG_DEBUG, "Failed to reinitialize ctrl_iface socket");
 219                                 }
 220                         }
 221                         if (new_attached) {
 222                                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to send response to ATTACH - detaching");
 223                                 new_attached = 0;
 224                                 wpa_supplicant_ctrl_iface_detach(
 225                                         &priv->ctrl_dst, &from, fromlen);
 226                         }
 227                 }
 228         }
 229         os_free(reply_buf);
 230
 231         if (new_attached)
 232                 eapol_sm_notify_ctrl_attached(wpa_s->eapol);
 233 }
 234
 235
 236 static char * wpa_supplicant_ctrl_iface_path(struct wpa_supplicant *wpa_s)
 237 {
 238         char *buf;
 239         size_t len;
 240         char *pbuf, *dir = NULL, *gid_str = NULL;
 241         int res;
 242
 243         if (wpa_s->conf->ctrl_interface == NULL)
 244                 return NULL;
 245
 246         pbuf = os_strdup(wpa_s->conf->ctrl_interface);
 247         if (pbuf == NULL)
 248                 return NULL;
 249         if (os_strncmp(pbuf, "DIR=", 4) == 0) {
 250                 dir = pbuf + 4;
 251                 gid_str = os_strstr(dir, " GROUP=");
 252                 if (gid_str) {
 253                         *gid_str = '\0';
 254                         gid_str += 7;
 255                 }
 256         } else
 257                 dir = pbuf;
 258
 259         len = os_strlen(dir) + os_strlen(wpa_s->ifname) + 2;
 260         buf = os_malloc(len);
 261         if (buf == NULL) {
 262                 os_free(pbuf);
 263                 return NULL;
 264         }
 265
 266         res = os_snprintf(buf, len, "%s/%s", dir, wpa_s->ifname);
 267         if (res < 0 || (size_t) res >= len) {
 268                 os_free(pbuf);
 269                 os_free(buf);
 270                 return NULL;
 271         }
 272 #ifdef __CYGWIN__
 273         {
 274                 /* Windows/WinPcap uses interface names that are not suitable
 275                  * as a file name - convert invalid chars to underscores */
 276                 char *pos = buf;
 277                 while (*pos) {
 278                         if (*pos == '\\')
 279                                 *pos = '_';
 280                         pos++;
 281                 }
 282         }
 283 #endif /* __CYGWIN__ */
 284         os_free(pbuf);
 285         return buf;
 286 }
 287
 288
 289 static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level, int global,
 290                                              const char *txt, size_t len)
 291 {
 292         struct wpa_supplicant *wpa_s = ctx;
 293
 294         if (wpa_s == NULL)
 295                 return;
 296
 297         if (global != 2 && wpa_s->global->ctrl_iface) {
 298                 struct ctrl_iface_global_priv *priv = wpa_s->global->ctrl_iface;
 299                 if (!dl_list_empty(&priv->ctrl_dst)) {
 300                         wpa_supplicant_ctrl_iface_send(wpa_s, global ? NULL :
 301                                                        wpa_s->ifname,
 302                                                        priv->sock,
 303                                                        &priv->ctrl_dst,
 304                                                        level, txt, len, NULL,
 305                                                        priv);
 306                 }
 307         }
 308
 309         if (wpa_s->ctrl_iface == NULL)
 310                 return;
 311         wpa_supplicant_ctrl_iface_send(wpa_s, NULL, wpa_s->ctrl_iface->sock,
 312                                        &wpa_s->ctrl_iface->ctrl_dst,
 313                                        level, txt, len, wpa_s->ctrl_iface,
 314                                        NULL);
 315 }
 316
 317
 318 static int wpas_ctrl_iface_open_sock(struct wpa_supplicant *wpa_s,
 319                                      struct ctrl_iface_priv *priv)
 320 {
 321         struct sockaddr_un addr;
 322         char *fname = NULL;
 323         gid_t gid = 0;
 324         int gid_set = 0;
 325         char *buf, *dir = NULL, *gid_str = NULL;
 326         struct group *grp;
 327         char *endp;
 328         int flags;
 329
 330         buf = os_strdup(wpa_s->conf->ctrl_interface);
 331         if (buf == NULL)
 332                 goto fail;
 333 #ifdef ANDROID
 334         os_snprintf(addr.sun_path, sizeof(addr.sun_path), "wpa_%s",
 335                     wpa_s->conf->ctrl_interface);
 336         priv->sock = android_get_control_socket(addr.sun_path);
 337         if (priv->sock >= 0)
 338                 goto havesock;
 339 #endif /* ANDROID */
 340         if (os_strncmp(buf, "DIR=", 4) == 0) {
 341                 dir = buf + 4;
 342                 gid_str = os_strstr(dir, " GROUP=");
 343                 if (gid_str) {
 344                         *gid_str = '\0';
 345                         gid_str += 7;
 346                 }
 347         } else {
 348                 dir = buf;
 349                 gid_str = wpa_s->conf->ctrl_interface_group;
 350         }
 351
 352         if (mkdir(dir, S_IRWXU | S_IRWXG) < 0) {
 353                 if (errno == EEXIST) {
 354                         wpa_printf(MSG_DEBUG, "Using existing control "
 355                                    "interface directory.");
 356                 } else {
 357                         wpa_printf(MSG_ERROR, "mkdir[ctrl_interface=%s]: %s",
 358                                    dir, strerror(errno));
 359                         goto fail;
 360                 }
 361         }
 362
 363 #ifdef ANDROID
 364         /*
 365          * wpa_supplicant is started from /init.*.rc on Android and that seems
 366          * to be using umask 0077 which would leave the control interface
 367          * directory without group access. This breaks things since Wi-Fi
 368          * framework assumes that this directory can be accessed by other
 369          * applications in the wifi group. Fix this by adding group access even
 370          * if umask value would prevent this.
 371          */
 372         if (chmod(dir, S_IRWXU | S_IRWXG) < 0) {
 373                 wpa_printf(MSG_ERROR, "CTRL: Could not chmod directory: %s",
 374                            strerror(errno));
 375                 /* Try to continue anyway */
 376         }
 377 #endif /* ANDROID */
 378
 379         if (gid_str) {
 380                 grp = getgrnam(gid_str);
 381                 if (grp) {
 382                         gid = grp->gr_gid;
 383                         gid_set = 1;
 384                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 385                                    " (from group name '%s')",
 386                                    (int) gid, gid_str);
 387                 } else {
 388                         /* Group name not found - try to parse this as gid */
 389                         gid = strtol(gid_str, &endp, 10);
 390                         if (*gid_str == '\0' || *endp != '\0') {
 391                                 wpa_printf(MSG_ERROR, "CTRL: Invalid group "
 392                                            "'%s'", gid_str);
 393                                 goto fail;
 394                         }
 395                         gid_set = 1;
 396                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 397                                    (int) gid);
 398                 }
 399         }
 400
 401         if (gid_set && chown(dir, -1, gid) < 0) {
 402                 wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
 403                            dir, (int) gid, strerror(errno));
 404                 goto fail;
 405         }
 406
 407         /* Make sure the group can enter and read the directory */
 408         if (gid_set &&
 409             chmod(dir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP) < 0) {
 410                 wpa_printf(MSG_ERROR, "CTRL: chmod[ctrl_interface]: %s",
 411                            strerror(errno));
 412                 goto fail;
 413         }
 414
 415         if (os_strlen(dir) + 1 + os_strlen(wpa_s->ifname) >=
 416             sizeof(addr.sun_path)) {
 417                 wpa_printf(MSG_ERROR, "ctrl_iface path limit exceeded");
 418                 goto fail;
 419         }
 420
 421         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 422         if (priv->sock < 0) {
 423                 wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
 424                 goto fail;
 425         }
 426
 427         os_memset(&addr, 0, sizeof(addr));
 428 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 429         addr.sun_len = sizeof(addr);
 430 #endif /* __FreeBSD__ */
 431         addr.sun_family = AF_UNIX;
 432         fname = wpa_supplicant_ctrl_iface_path(wpa_s);
 433         if (fname == NULL)
 434                 goto fail;
 435         os_strlcpy(addr.sun_path, fname, sizeof(addr.sun_path));
 436         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 437                 wpa_printf(MSG_DEBUG, "ctrl_iface bind(PF_UNIX) failed: %s",
 438                            strerror(errno));
 439                 if (connect(priv->sock, (struct sockaddr *) &addr,
 440                             sizeof(addr)) < 0) {
 441                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 442                                    " allow connections - assuming it was left"
 443                                    "over from forced program termination");
 444                         if (unlink(fname) < 0) {
 445                                 wpa_printf(MSG_ERROR,
 446                                            "Could not unlink existing ctrl_iface socket '%s': %s",
 447                                            fname, strerror(errno));
 448                                 goto fail;
 449                         }
 450                         if (bind(priv->sock, (struct sockaddr *) &addr,
 451                                  sizeof(addr)) < 0) {
 452                                 wpa_printf(MSG_ERROR, "supp-ctrl-iface-init: bind(PF_UNIX): %s",
 453                                            strerror(errno));
 454                                 goto fail;
 455                         }
 456                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 457                                    "ctrl_iface socket '%s'", fname);
 458                 } else {
 459                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 460                                    "be in use - cannot override it");
 461                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 462                                    "not used anymore", fname);
 463                         os_free(fname);
 464                         fname = NULL;
 465                         goto fail;
 466                 }
 467         }
 468
 469         if (gid_set && chown(fname, -1, gid) < 0) {
 470                 wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
 471                            fname, (int) gid, strerror(errno));
 472                 goto fail;
 473         }
 474
 475         if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
 476                 wpa_printf(MSG_ERROR, "chmod[ctrl_interface=%s]: %s",
 477                            fname, strerror(errno));
 478                 goto fail;
 479         }
 480         os_free(fname);
 481
 482 #ifdef ANDROID
 483 havesock:
 484 #endif /* ANDROID */
 485
 486         /*
 487          * Make socket non-blocking so that we don't hang forever if
 488          * target dies unexpectedly.
 489          */
 490         flags = fcntl(priv->sock, F_GETFL);
 491         if (flags >= 0) {
 492                 flags |= O_NONBLOCK;
 493                 if (fcntl(priv->sock, F_SETFL, flags) < 0) {
 494                         wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
 495                                    strerror(errno));
 496                         /* Not fatal, continue on.*/
 497                 }
 498         }
 499
 500         eloop_register_read_sock(priv->sock, wpa_supplicant_ctrl_iface_receive,
 501                                  wpa_s, priv);
 502         wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
 503
 504         os_free(buf);
 505         return 0;
 506
 507 fail:
 508         if (priv->sock >= 0) {
 509                 close(priv->sock);
 510                 priv->sock = -1;
 511         }
 512         if (fname) {
 513                 unlink(fname);
 514                 os_free(fname);
 515         }
 516         os_free(buf);
 517         return -1;
 518 }
 519
 520
 521 struct ctrl_iface_priv *
 522 wpa_supplicant_ctrl_iface_init(struct wpa_supplicant *wpa_s)
 523 {
 524         struct ctrl_iface_priv *priv;
 525
 526         priv = os_zalloc(sizeof(*priv));
 527         if (priv == NULL)
 528                 return NULL;
 529         dl_list_init(&priv->ctrl_dst);
 530         priv->wpa_s = wpa_s;
 531         priv->sock = -1;
 532
 533         if (wpa_s->conf->ctrl_interface == NULL)
 534                 return priv;
 535
 536         if (wpas_ctrl_iface_open_sock(wpa_s, priv) < 0) {
 537                 os_free(priv);
 538                 return NULL;
 539         }
 540
 541         return priv;
 542 }
 543
 544
 545 static int wpas_ctrl_iface_reinit(struct wpa_supplicant *wpa_s,
 546                                   struct ctrl_iface_priv *priv)
 547 {
 548         int res;
 549
 550         if (priv->sock <= 0)
 551                 return -1;
 552
 553         eloop_unregister_read_sock(priv->sock);
 554         close(priv->sock);
 555         priv->sock = -1;
 556         res = wpas_ctrl_iface_open_sock(wpa_s, priv);
 557         if (res < 0)
 558                 return -1;
 559         return priv->sock;
 560 }
 561
 562
 563 void wpa_supplicant_ctrl_iface_deinit(struct ctrl_iface_priv *priv)
 564 {
 565         struct wpa_ctrl_dst *dst, *prev;
 566
 567         if (priv->sock > -1) {
 568                 char *fname;
 569                 char *buf, *dir = NULL, *gid_str = NULL;
 570                 eloop_unregister_read_sock(priv->sock);
 571                 if (!dl_list_empty(&priv->ctrl_dst)) {
 572                         /*
 573                          * Wait before closing the control socket if
 574                          * there are any attached monitors in order to allow
 575                          * them to receive any pending messages.
 576                          */
 577                         wpa_printf(MSG_DEBUG, "CTRL_IFACE wait for attached "
 578                                    "monitors to receive messages");
 579                         os_sleep(0, 100000);
 580                 }
 581                 close(priv->sock);
 582                 priv->sock = -1;
 583                 fname = wpa_supplicant_ctrl_iface_path(priv->wpa_s);
 584                 if (fname) {
 585                         unlink(fname);
 586                         os_free(fname);
 587                 }
 588
 589                 if (priv->wpa_s->conf->ctrl_interface == NULL)
 590                         goto free_dst;
 591                 buf = os_strdup(priv->wpa_s->conf->ctrl_interface);
 592                 if (buf == NULL)
 593                         goto free_dst;
 594                 if (os_strncmp(buf, "DIR=", 4) == 0) {
 595                         dir = buf + 4;
 596                         gid_str = os_strstr(dir, " GROUP=");
 597                         if (gid_str) {
 598                                 *gid_str = '\0';
 599                                 gid_str += 7;
 600                         }
 601                 } else
 602                         dir = buf;
 603
 604                 if (rmdir(dir) < 0) {
 605                         if (errno == ENOTEMPTY) {
 606                                 wpa_printf(MSG_DEBUG, "Control interface "
 607                                            "directory not empty - leaving it "
 608                                            "behind");
 609                         } else {
 610                                 wpa_printf(MSG_ERROR,
 611                                            "rmdir[ctrl_interface=%s]: %s",
 612                                            dir, strerror(errno));
 613                         }
 614                 }
 615                 os_free(buf);
 616         }
 617
 618 free_dst:
 619         dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
 620                               list)
 621                 os_free(dst);
 622         os_free(priv);
 623 }
 624
 625
 626 /**
 627  * wpa_supplicant_ctrl_iface_send - Send a control interface packet to monitors
 628  * @ifname: Interface name for global control socket or %NULL
 629  * @sock: Local socket fd
 630  * @ctrl_dst: List of attached listeners
 631  * @level: Priority level of the message
 632  * @buf: Message data
 633  * @len: Message length
 634  *
 635  * Send a packet to all monitor programs attached to the control interface.
 636  */
 637 static void wpa_supplicant_ctrl_iface_send(struct wpa_supplicant *wpa_s,
 638                                            const char *ifname, int sock,
 639                                            struct dl_list *ctrl_dst,
 640                                            int level, const char *buf,
 641                                            size_t len,
 642                                            struct ctrl_iface_priv *priv,
 643                                            struct ctrl_iface_global_priv *gp)
 644 {
 645         struct wpa_ctrl_dst *dst, *next;
 646         char levelstr[10];
 647         int idx, res;
 648         struct msghdr msg;
 649         struct iovec io[5];
 650
 651         if (sock < 0 || dl_list_empty(ctrl_dst))
 652                 return;
 653
 654         res = os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);
 655         if (res < 0 || (size_t) res >= sizeof(levelstr))
 656                 return;
 657         idx = 0;
 658         if (ifname) {
 659                 io[idx].iov_base = "IFNAME=";
 660                 io[idx].iov_len = 7;
 661                 idx++;
 662                 io[idx].iov_base = (char *) ifname;
 663                 io[idx].iov_len = os_strlen(ifname);
 664                 idx++;
 665                 io[idx].iov_base = " ";
 666                 io[idx].iov_len = 1;
 667                 idx++;
 668         }
 669         io[idx].iov_base = levelstr;
 670         io[idx].iov_len = os_strlen(levelstr);
 671         idx++;
 672         io[idx].iov_base = (char *) buf;
 673         io[idx].iov_len = len;
 674         idx++;
 675         os_memset(&msg, 0, sizeof(msg));
 676         msg.msg_iov = io;
 677         msg.msg_iovlen = idx;
 678
 679         idx = -1;
 680         dl_list_for_each_safe(dst, next, ctrl_dst, struct wpa_ctrl_dst, list) {
 681                 int _errno;
 682
 683                 idx++;
 684                 if (level < dst->debug_level)
 685                         continue;
 686
 687                 wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor send",
 688                             (u8 *) dst->addr.sun_path, dst->addrlen -
 689                             offsetof(struct sockaddr_un, sun_path));
 690                 msg.msg_name = (void *) &dst->addr;
 691                 msg.msg_namelen = dst->addrlen;
 692                 if (sendmsg(sock, &msg, MSG_DONTWAIT) >= 0) {
 693                         dst->errors = 0;
 694                         idx++;
 695                         continue;
 696                 }
 697
 698                 _errno = errno;
 699                 wpa_printf(MSG_INFO, "CTRL_IFACE monitor[%d]: %d - %s",
 700                            idx, errno, strerror(errno));
 701                 dst->errors++;
 702
 703                 if (dst->errors > 10 || _errno == ENOENT || _errno == EPERM) {
 704                         wpa_printf(MSG_INFO, "CTRL_IFACE: Detach monitor that cannot receive messages");
 705                         wpa_supplicant_ctrl_iface_detach(ctrl_dst, &dst->addr,
 706                                                          dst->addrlen);
 707                 }
 708
 709                 if (_errno == ENOBUFS || _errno == EAGAIN) {
 710                         /*
 711                          * The socket send buffer could be full. This may happen
 712                          * if client programs are not receiving their pending
 713                          * messages. Close and reopen the socket as a workaround
 714                          * to avoid getting stuck being unable to send any new
 715                          * responses.
 716                          */
 717                         if (priv)
 718                                 sock = wpas_ctrl_iface_reinit(wpa_s, priv);
 719                         else if (gp)
 720                                 sock = wpas_ctrl_iface_global_reinit(
 721                                         wpa_s->global, gp);
 722                         else
 723                                 break;
 724                         if (sock < 0) {
 725                                 wpa_dbg(wpa_s, MSG_DEBUG,
 726                                         "Failed to reinitialize ctrl_iface socket");
 727                                 break;
 728                         }
 729                 }
 730         }
 731 }
 732
 733
 734 void wpa_supplicant_ctrl_iface_wait(struct ctrl_iface_priv *priv)
 735 {
 736         char buf[256];
 737         int res;
 738         struct sockaddr_un from;
 739         socklen_t fromlen = sizeof(from);
 740
 741         for (;;) {
 742                 wpa_printf(MSG_DEBUG, "CTRL_IFACE - %s - wait for monitor to "
 743                            "attach", priv->wpa_s->ifname);
 744                 eloop_wait_for_read_sock(priv->sock);
 745
 746                 res = recvfrom(priv->sock, buf, sizeof(buf) - 1, 0,
 747                                (struct sockaddr *) &from, &fromlen);
 748                 if (res < 0) {
 749                         wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 750                                    strerror(errno));
 751                         continue;
 752                 }
 753                 buf[res] = '\0';
 754
 755                 if (os_strcmp(buf, "ATTACH") == 0) {
 756                         /* handle ATTACH signal of first monitor interface */
 757                         if (!wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst,
 758                                                               &from, fromlen)) {
 759                                 if (sendto(priv->sock, "OK\n", 3, 0,
 760                                            (struct sockaddr *) &from, fromlen) <
 761                                     0) {
 762                                         wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
 763                                                    strerror(errno));
 764                                 }
 765                                 /* OK to continue */
 766                                 return;
 767                         } else {
 768                                 if (sendto(priv->sock, "FAIL\n", 5, 0,
 769                                            (struct sockaddr *) &from, fromlen) <
 770                                     0) {
 771                                         wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
 772                                                    strerror(errno));
 773                                 }
 774                         }
 775                 } else {
 776                         /* return FAIL for all other signals */
 777                         if (sendto(priv->sock, "FAIL\n", 5, 0,
 778                                    (struct sockaddr *) &from, fromlen) < 0) {
 779                                 wpa_printf(MSG_DEBUG,
 780                                            "ctrl_iface sendto failed: %s",
 781                                            strerror(errno));
 782                         }
 783                 }
 784         }
 785 }
 786
 787
 788 /* Global ctrl_iface */
 789
 790 static void wpa_supplicant_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 791                                                      void *sock_ctx)
 792 {
 793         struct wpa_global *global = eloop_ctx;
 794         struct ctrl_iface_global_priv *priv = sock_ctx;
 795         char buf[256];
 796         int res;
 797         struct sockaddr_un from;
 798         socklen_t fromlen = sizeof(from);
 799         char *reply = NULL, *reply_buf = NULL;
 800         size_t reply_len;
 801
 802         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 803                        (struct sockaddr *) &from, &fromlen);
 804         if (res < 0) {
 805                 wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 806                            strerror(errno));
 807                 return;
 808         }
 809         buf[res] = '\0';
 810
 811         if (os_strcmp(buf, "ATTACH") == 0) {
 812                 if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
 813                                                      fromlen))
 814                         reply_len = 1;
 815                 else
 816                         reply_len = 2;
 817         } else if (os_strcmp(buf, "DETACH") == 0) {
 818                 if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
 819                                                      fromlen))
 820                         reply_len = 1;
 821                 else
 822                         reply_len = 2;
 823         } else {
 824                 reply_buf = wpa_supplicant_global_ctrl_iface_process(
 825                         global, buf, &reply_len);
 826                 reply = reply_buf;
 827         }
 828
 829         if (!reply && reply_len == 1) {
 830                 reply = "FAIL\n";
 831                 reply_len = 5;
 832         } else if (!reply && reply_len == 2) {
 833                 reply = "OK\n";
 834                 reply_len = 3;
 835         }
 836
 837         if (reply) {
 838                 if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 839                            fromlen) < 0) {
 840                         wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
 841                                 strerror(errno));
 842                 }
 843         }
 844         os_free(reply_buf);
 845 }
 846
 847
 848 static int wpas_global_ctrl_iface_open_sock(struct wpa_global *global,
 849                                             struct ctrl_iface_global_priv *priv)
 850 {
 851         struct sockaddr_un addr;
 852         const char *ctrl = global->params.ctrl_interface;
 853         int flags;
 854
 855         wpa_printf(MSG_DEBUG, "Global control interface '%s'", ctrl);
 856
 857 #ifdef ANDROID
 858         if (os_strncmp(ctrl, "@android:", 9) == 0) {
 859                 priv->sock = android_get_control_socket(ctrl + 9);
 860                 if (priv->sock < 0) {
 861                         wpa_printf(MSG_ERROR, "Failed to open Android control "
 862                                    "socket '%s'", ctrl + 9);
 863                         goto fail;
 864                 }
 865                 wpa_printf(MSG_DEBUG, "Using Android control socket '%s'",
 866                            ctrl + 9);
 867                 goto havesock;
 868         }
 869
 870         if (os_strncmp(ctrl, "@abstract:", 10) != 0) {
 871                 /*
 872                  * Backwards compatibility - try to open an Android control
 873                  * socket and if that fails, assume this was a UNIX domain
 874                  * socket instead.
 875                  */
 876                 priv->sock = android_get_control_socket(ctrl);
 877                 if (priv->sock >= 0) {
 878                         wpa_printf(MSG_DEBUG,
 879                                    "Using Android control socket '%s'",
 880                                    ctrl);
 881                         goto havesock;
 882                 }
 883         }
 884 #endif /* ANDROID */
 885
 886         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 887         if (priv->sock < 0) {
 888                 wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
 889                 goto fail;
 890         }
 891
 892         os_memset(&addr, 0, sizeof(addr));
 893 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 894         addr.sun_len = sizeof(addr);
 895 #endif /* __FreeBSD__ */
 896         addr.sun_family = AF_UNIX;
 897
 898         if (os_strncmp(ctrl, "@abstract:", 10) == 0) {
 899                 addr.sun_path[0] = '\0';
 900                 os_strlcpy(addr.sun_path + 1, ctrl + 10,
 901                            sizeof(addr.sun_path) - 1);
 902                 if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) <
 903                     0) {
 904                         wpa_printf(MSG_ERROR, "supp-global-ctrl-iface-init: "
 905                                    "bind(PF_UNIX;%s) failed: %s",
 906                                    ctrl, strerror(errno));
 907                         goto fail;
 908                 }
 909                 wpa_printf(MSG_DEBUG, "Using Abstract control socket '%s'",
 910                            ctrl + 10);
 911                 goto havesock;
 912         }
 913
 914         os_strlcpy(addr.sun_path, ctrl, sizeof(addr.sun_path));
 915         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 916                 wpa_printf(MSG_INFO, "supp-global-ctrl-iface-init(%s) (will try fixup): bind(PF_UNIX): %s",
 917                            ctrl, strerror(errno));
 918                 if (connect(priv->sock, (struct sockaddr *) &addr,
 919                             sizeof(addr)) < 0) {
 920                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 921                                    " allow connections - assuming it was left"
 922                                    "over from forced program termination");
 923                         if (unlink(ctrl) < 0) {
 924                                 wpa_printf(MSG_ERROR,
 925                                            "Could not unlink existing ctrl_iface socket '%s': %s",
 926                                            ctrl, strerror(errno));
 927                                 goto fail;
 928                         }
 929                         if (bind(priv->sock, (struct sockaddr *) &addr,
 930                                  sizeof(addr)) < 0) {
 931                                 wpa_printf(MSG_ERROR, "supp-glb-iface-init: bind(PF_UNIX;%s): %s",
 932                                            ctrl, strerror(errno));
 933                                 goto fail;
 934                         }
 935                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 936                                    "ctrl_iface socket '%s'",
 937                                    ctrl);
 938                 } else {
 939                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 940                                    "be in use - cannot override it");
 941                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 942                                    "not used anymore",
 943                                    ctrl);
 944                         goto fail;
 945                 }
 946         }
 947
 948         wpa_printf(MSG_DEBUG, "Using UNIX control socket '%s'", ctrl);
 949
 950         if (global->params.ctrl_interface_group) {
 951                 char *gid_str = global->params.ctrl_interface_group;
 952                 gid_t gid = 0;
 953                 struct group *grp;
 954                 char *endp;
 955
 956                 grp = getgrnam(gid_str);
 957                 if (grp) {
 958                         gid = grp->gr_gid;
 959                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 960                                    " (from group name '%s')",
 961                                    (int) gid, gid_str);
 962                 } else {
 963                         /* Group name not found - try to parse this as gid */
 964                         gid = strtol(gid_str, &endp, 10);
 965                         if (*gid_str == '\0' || *endp != '\0') {
 966                                 wpa_printf(MSG_ERROR, "CTRL: Invalid group "
 967                                            "'%s'", gid_str);
 968                                 goto fail;
 969                         }
 970                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 971                                    (int) gid);
 972                 }
 973                 if (chown(ctrl, -1, gid) < 0) {
 974                         wpa_printf(MSG_ERROR,
 975                                    "chown[global_ctrl_interface=%s,gid=%d]: %s",
 976                                    ctrl, (int) gid, strerror(errno));
 977                         goto fail;
 978                 }
 979
 980                 if (chmod(ctrl, S_IRWXU | S_IRWXG) < 0) {
 981                         wpa_printf(MSG_ERROR,
 982                                    "chmod[global_ctrl_interface=%s]: %s",
 983                                    ctrl, strerror(errno));
 984                         goto fail;
 985                 }
 986         } else {
 987                 chmod(ctrl, S_IRWXU);
 988         }
 989
 990 havesock:
 991
 992         /*
 993          * Make socket non-blocking so that we don't hang forever if
 994          * target dies unexpectedly.
 995          */
 996         flags = fcntl(priv->sock, F_GETFL);
 997         if (flags >= 0) {
 998                 flags |= O_NONBLOCK;
 999                 if (fcntl(priv->sock, F_SETFL, flags) < 0) {
1000                         wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
1001                                    strerror(errno));
1002                         /* Not fatal, continue on.*/
1003                 }
1004         }
1005
1006         eloop_register_read_sock(priv->sock,
1007                                  wpa_supplicant_global_ctrl_iface_receive,
1008                                  global, priv);
1009
1010         return 0;
1011
1012 fail:
1013         if (priv->sock >= 0) {
1014                 close(priv->sock);
1015                 priv->sock = -1;
1016         }
1017         return -1;
1018 }
1019
1020
1021 struct ctrl_iface_global_priv *
1022 wpa_supplicant_global_ctrl_iface_init(struct wpa_global *global)
1023 {
1024         struct ctrl_iface_global_priv *priv;
1025
1026         priv = os_zalloc(sizeof(*priv));
1027         if (priv == NULL)
1028                 return NULL;
1029         dl_list_init(&priv->ctrl_dst);
1030         priv->global = global;
1031         priv->sock = -1;
1032
1033         if (global->params.ctrl_interface == NULL)
1034                 return priv;
1035
1036         if (wpas_global_ctrl_iface_open_sock(global, priv) < 0) {
1037                 os_free(priv);
1038                 return NULL;
1039         }
1040
1041         wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
1042
1043         return priv;
1044 }
1045
1046
1047 static int wpas_ctrl_iface_global_reinit(struct wpa_global *global,
1048                                          struct ctrl_iface_global_priv *priv)
1049 {
1050         int res;
1051
1052         if (priv->sock <= 0)
1053                 return -1;
1054
1055         eloop_unregister_read_sock(priv->sock);
1056         close(priv->sock);
1057         priv->sock = -1;
1058         res = wpas_global_ctrl_iface_open_sock(global, priv);
1059         if (res < 0)
1060                 return -1;
1061         return priv->sock;
1062 }
1063
1064
1065 void
1066 wpa_supplicant_global_ctrl_iface_deinit(struct ctrl_iface_global_priv *priv)
1067 {
1068         struct wpa_ctrl_dst *dst, *prev;
1069
1070         if (priv->sock >= 0) {
1071                 eloop_unregister_read_sock(priv->sock);
1072                 close(priv->sock);
1073         }
1074         if (priv->global->params.ctrl_interface)
1075                 unlink(priv->global->params.ctrl_interface);
1076         dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
1077                               list)
1078                 os_free(dst);
1079         os_free(priv);
1080 }