wpa_supplicant/ctrl_iface_unix.c

   1 /*
   2  * WPA Supplicant / UNIX domain socket -based control interface
   3  * Copyright (c) 2004-2014, 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         char addr_txt[200];
  79
  80         dst = os_zalloc(sizeof(*dst));
  81         if (dst == NULL)
  82                 return -1;
  83         os_memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
  84         dst->addrlen = fromlen;
  85         dst->debug_level = MSG_INFO;
  86         dl_list_add(ctrl_dst, &dst->list);
  87         printf_encode(addr_txt, sizeof(addr_txt),
  88                       (u8 *) from->sun_path,
  89                       fromlen - offsetof(struct sockaddr_un, sun_path));
  90         wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor attached %s", addr_txt);
  91         return 0;
  92 }
  93
  94
  95 static int wpa_supplicant_ctrl_iface_detach(struct dl_list *ctrl_dst,
  96                                             struct sockaddr_un *from,
  97                                             socklen_t fromlen)
  98 {
  99         struct wpa_ctrl_dst *dst;
 100
 101         dl_list_for_each(dst, ctrl_dst, struct wpa_ctrl_dst, list) {
 102                 if (fromlen == dst->addrlen &&
 103                     os_memcmp(from->sun_path, dst->addr.sun_path,
 104                               fromlen - offsetof(struct sockaddr_un, sun_path))
 105                     == 0) {
 106                         char addr_txt[200];
 107                         printf_encode(addr_txt, sizeof(addr_txt),
 108                                       (u8 *) from->sun_path,
 109                                       fromlen -
 110                                       offsetof(struct sockaddr_un, sun_path));
 111                         wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor detached %s",
 112                                    addr_txt);
 113                         dl_list_del(&dst->list);
 114                         os_free(dst);
 115                         return 0;
 116                 }
 117         }
 118         return -1;
 119 }
 120
 121
 122 static int wpa_supplicant_ctrl_iface_level(struct ctrl_iface_priv *priv,
 123                                            struct sockaddr_un *from,
 124                                            socklen_t fromlen,
 125                                            char *level)
 126 {
 127         struct wpa_ctrl_dst *dst;
 128
 129         wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", level);
 130
 131         dl_list_for_each(dst, &priv->ctrl_dst, struct wpa_ctrl_dst, list) {
 132                 if (fromlen == dst->addrlen &&
 133                     os_memcmp(from->sun_path, dst->addr.sun_path,
 134                               fromlen - offsetof(struct sockaddr_un, sun_path))
 135                     == 0) {
 136                         char addr_txt[200];
 137                         dst->debug_level = atoi(level);
 138                         printf_encode(addr_txt, sizeof(addr_txt),
 139                                       (u8 *) from->sun_path, fromlen -
 140                                       offsetof(struct sockaddr_un, sun_path));
 141                         wpa_printf(MSG_DEBUG, "CTRL_IFACE changed monitor level to %d for %s",
 142                                    dst->debug_level, addr_txt);
 143                         return 0;
 144                 }
 145         }
 146
 147         return -1;
 148 }
 149
 150
 151 static void wpa_supplicant_ctrl_iface_receive(int sock, void *eloop_ctx,
 152                                               void *sock_ctx)
 153 {
 154         struct wpa_supplicant *wpa_s = eloop_ctx;
 155         struct ctrl_iface_priv *priv = sock_ctx;
 156         char buf[4096];
 157         int res;
 158         struct sockaddr_un from;
 159         socklen_t fromlen = sizeof(from);
 160         char *reply = NULL, *reply_buf = NULL;
 161         size_t reply_len = 0;
 162         int new_attached = 0;
 163
 164         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 165                        (struct sockaddr *) &from, &fromlen);
 166         if (res < 0) {
 167                 wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 168                            strerror(errno));
 169                 return;
 170         }
 171         buf[res] = '\0';
 172
 173         if (os_strcmp(buf, "ATTACH") == 0) {
 174                 if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
 175                                                      fromlen))
 176                         reply_len = 1;
 177                 else {
 178                         new_attached = 1;
 179                         reply_len = 2;
 180                 }
 181         } else if (os_strcmp(buf, "DETACH") == 0) {
 182                 if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
 183                                                      fromlen))
 184                         reply_len = 1;
 185                 else
 186                         reply_len = 2;
 187         } else if (os_strncmp(buf, "LEVEL ", 6) == 0) {
 188                 if (wpa_supplicant_ctrl_iface_level(priv, &from, fromlen,
 189                                                     buf + 6))
 190                         reply_len = 1;
 191                 else
 192                         reply_len = 2;
 193         } else {
 194                 reply_buf = wpa_supplicant_ctrl_iface_process(wpa_s, buf,
 195                                                               &reply_len);
 196                 reply = reply_buf;
 197         }
 198
 199         if (!reply && reply_len == 1) {
 200                 reply = "FAIL\n";
 201                 reply_len = 5;
 202         } else if (!reply && reply_len == 2) {
 203                 reply = "OK\n";
 204                 reply_len = 3;
 205         }
 206
 207         if (reply) {
 208                 if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 209                            fromlen) < 0) {
 210                         int _errno = errno;
 211                         wpa_dbg(wpa_s, MSG_DEBUG,
 212                                 "ctrl_iface sendto failed: %d - %s",
 213                                 _errno, strerror(_errno));
 214                         if (_errno == ENOBUFS || _errno == EAGAIN) {
 215                                 /*
 216                                  * The socket send buffer could be full. This
 217                                  * may happen if client programs are not
 218                                  * receiving their pending messages. Close and
 219                                  * reopen the socket as a workaround to avoid
 220                                  * getting stuck being unable to send any new
 221                                  * responses.
 222                                  */
 223                                 sock = wpas_ctrl_iface_reinit(wpa_s, priv);
 224                                 if (sock < 0) {
 225                                         wpa_dbg(wpa_s, MSG_DEBUG, "Failed to reinitialize ctrl_iface socket");
 226                                 }
 227                         }
 228                         if (new_attached) {
 229                                 wpa_dbg(wpa_s, MSG_DEBUG, "Failed to send response to ATTACH - detaching");
 230                                 new_attached = 0;
 231                                 wpa_supplicant_ctrl_iface_detach(
 232                                         &priv->ctrl_dst, &from, fromlen);
 233                         }
 234                 }
 235         }
 236         os_free(reply_buf);
 237
 238         if (new_attached)
 239                 eapol_sm_notify_ctrl_attached(wpa_s->eapol);
 240 }
 241
 242
 243 static char * wpa_supplicant_ctrl_iface_path(struct wpa_supplicant *wpa_s)
 244 {
 245         char *buf;
 246         size_t len;
 247         char *pbuf, *dir = NULL;
 248         int res;
 249
 250         if (wpa_s->conf->ctrl_interface == NULL)
 251                 return NULL;
 252
 253         pbuf = os_strdup(wpa_s->conf->ctrl_interface);
 254         if (pbuf == NULL)
 255                 return NULL;
 256         if (os_strncmp(pbuf, "DIR=", 4) == 0) {
 257                 char *gid_str;
 258                 dir = pbuf + 4;
 259                 gid_str = os_strstr(dir, " GROUP=");
 260                 if (gid_str)
 261                         *gid_str = '\0';
 262         } else
 263                 dir = pbuf;
 264
 265         len = os_strlen(dir) + os_strlen(wpa_s->ifname) + 2;
 266         buf = os_malloc(len);
 267         if (buf == NULL) {
 268                 os_free(pbuf);
 269                 return NULL;
 270         }
 271
 272         res = os_snprintf(buf, len, "%s/%s", dir, wpa_s->ifname);
 273         if (res < 0 || (size_t) res >= len) {
 274                 os_free(pbuf);
 275                 os_free(buf);
 276                 return NULL;
 277         }
 278 #ifdef __CYGWIN__
 279         {
 280                 /* Windows/WinPcap uses interface names that are not suitable
 281                  * as a file name - convert invalid chars to underscores */
 282                 char *pos = buf;
 283                 while (*pos) {
 284                         if (*pos == '\\')
 285                                 *pos = '_';
 286                         pos++;
 287                 }
 288         }
 289 #endif /* __CYGWIN__ */
 290         os_free(pbuf);
 291         return buf;
 292 }
 293
 294
 295 static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level, int global,
 296                                              const char *txt, size_t len)
 297 {
 298         struct wpa_supplicant *wpa_s = ctx;
 299
 300         if (wpa_s == NULL)
 301                 return;
 302
 303         if (global != 2 && wpa_s->global->ctrl_iface) {
 304                 struct ctrl_iface_global_priv *priv = wpa_s->global->ctrl_iface;
 305                 if (!dl_list_empty(&priv->ctrl_dst)) {
 306                         wpa_supplicant_ctrl_iface_send(wpa_s, global ? NULL :
 307                                                        wpa_s->ifname,
 308                                                        priv->sock,
 309                                                        &priv->ctrl_dst,
 310                                                        level, txt, len, NULL,
 311                                                        priv);
 312                 }
 313         }
 314
 315         if (wpa_s->ctrl_iface == NULL)
 316                 return;
 317         wpa_supplicant_ctrl_iface_send(wpa_s, NULL, wpa_s->ctrl_iface->sock,
 318                                        &wpa_s->ctrl_iface->ctrl_dst,
 319                                        level, txt, len, wpa_s->ctrl_iface,
 320                                        NULL);
 321 }
 322
 323
 324 static int wpas_ctrl_iface_open_sock(struct wpa_supplicant *wpa_s,
 325                                      struct ctrl_iface_priv *priv)
 326 {
 327         struct sockaddr_un addr;
 328         char *fname = NULL;
 329         gid_t gid = 0;
 330         int gid_set = 0;
 331         char *buf, *dir = NULL, *gid_str = NULL;
 332         struct group *grp;
 333         char *endp;
 334         int flags;
 335
 336         buf = os_strdup(wpa_s->conf->ctrl_interface);
 337         if (buf == NULL)
 338                 goto fail;
 339 #ifdef ANDROID
 340         os_snprintf(addr.sun_path, sizeof(addr.sun_path), "wpa_%s",
 341                     wpa_s->conf->ctrl_interface);
 342         priv->sock = android_get_control_socket(addr.sun_path);
 343         if (priv->sock >= 0)
 344                 goto havesock;
 345 #endif /* ANDROID */
 346         if (os_strncmp(buf, "DIR=", 4) == 0) {
 347                 dir = buf + 4;
 348                 gid_str = os_strstr(dir, " GROUP=");
 349                 if (gid_str) {
 350                         *gid_str = '\0';
 351                         gid_str += 7;
 352                 }
 353         } else {
 354                 dir = buf;
 355                 gid_str = wpa_s->conf->ctrl_interface_group;
 356         }
 357
 358         if (mkdir(dir, S_IRWXU | S_IRWXG) < 0) {
 359                 if (errno == EEXIST) {
 360                         wpa_printf(MSG_DEBUG, "Using existing control "
 361                                    "interface directory.");
 362                 } else {
 363                         wpa_printf(MSG_ERROR, "mkdir[ctrl_interface=%s]: %s",
 364                                    dir, strerror(errno));
 365                         goto fail;
 366                 }
 367         }
 368
 369 #ifdef ANDROID
 370         /*
 371          * wpa_supplicant is started from /init.*.rc on Android and that seems
 372          * to be using umask 0077 which would leave the control interface
 373          * directory without group access. This breaks things since Wi-Fi
 374          * framework assumes that this directory can be accessed by other
 375          * applications in the wifi group. Fix this by adding group access even
 376          * if umask value would prevent this.
 377          */
 378         if (chmod(dir, S_IRWXU | S_IRWXG) < 0) {
 379                 wpa_printf(MSG_ERROR, "CTRL: Could not chmod directory: %s",
 380                            strerror(errno));
 381                 /* Try to continue anyway */
 382         }
 383 #endif /* ANDROID */
 384
 385         if (gid_str) {
 386                 grp = getgrnam(gid_str);
 387                 if (grp) {
 388                         gid = grp->gr_gid;
 389                         gid_set = 1;
 390                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 391                                    " (from group name '%s')",
 392                                    (int) gid, gid_str);
 393                 } else {
 394                         /* Group name not found - try to parse this as gid */
 395                         gid = strtol(gid_str, &endp, 10);
 396                         if (*gid_str == '\0' || *endp != '\0') {
 397                                 wpa_printf(MSG_ERROR, "CTRL: Invalid group "
 398                                            "'%s'", gid_str);
 399                                 goto fail;
 400                         }
 401                         gid_set = 1;
 402                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 403                                    (int) gid);
 404                 }
 405         }
 406
 407         if (gid_set && chown(dir, -1, gid) < 0) {
 408                 wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
 409                            dir, (int) gid, strerror(errno));
 410                 goto fail;
 411         }
 412
 413         /* Make sure the group can enter and read the directory */
 414         if (gid_set &&
 415             chmod(dir, S_IRUSR | S_IWUSR | S_IXUSR | S_IRGRP | S_IXGRP) < 0) {
 416                 wpa_printf(MSG_ERROR, "CTRL: chmod[ctrl_interface]: %s",
 417                            strerror(errno));
 418                 goto fail;
 419         }
 420
 421         if (os_strlen(dir) + 1 + os_strlen(wpa_s->ifname) >=
 422             sizeof(addr.sun_path)) {
 423                 wpa_printf(MSG_ERROR, "ctrl_iface path limit exceeded");
 424                 goto fail;
 425         }
 426
 427         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 428         if (priv->sock < 0) {
 429                 wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
 430                 goto fail;
 431         }
 432
 433         os_memset(&addr, 0, sizeof(addr));
 434 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 435         addr.sun_len = sizeof(addr);
 436 #endif /* __FreeBSD__ */
 437         addr.sun_family = AF_UNIX;
 438         fname = wpa_supplicant_ctrl_iface_path(wpa_s);
 439         if (fname == NULL)
 440                 goto fail;
 441         os_strlcpy(addr.sun_path, fname, sizeof(addr.sun_path));
 442         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 443                 wpa_printf(MSG_DEBUG, "ctrl_iface bind(PF_UNIX) failed: %s",
 444                            strerror(errno));
 445                 if (connect(priv->sock, (struct sockaddr *) &addr,
 446                             sizeof(addr)) < 0) {
 447                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 448                                    " allow connections - assuming it was left"
 449                                    "over from forced program termination");
 450                         if (unlink(fname) < 0) {
 451                                 wpa_printf(MSG_ERROR,
 452                                            "Could not unlink existing ctrl_iface socket '%s': %s",
 453                                            fname, strerror(errno));
 454                                 goto fail;
 455                         }
 456                         if (bind(priv->sock, (struct sockaddr *) &addr,
 457                                  sizeof(addr)) < 0) {
 458                                 wpa_printf(MSG_ERROR, "supp-ctrl-iface-init: bind(PF_UNIX): %s",
 459                                            strerror(errno));
 460                                 goto fail;
 461                         }
 462                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 463                                    "ctrl_iface socket '%s'", fname);
 464                 } else {
 465                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 466                                    "be in use - cannot override it");
 467                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 468                                    "not used anymore", fname);
 469                         os_free(fname);
 470                         fname = NULL;
 471                         goto fail;
 472                 }
 473         }
 474
 475         if (gid_set && chown(fname, -1, gid) < 0) {
 476                 wpa_printf(MSG_ERROR, "chown[ctrl_interface=%s,gid=%d]: %s",
 477                            fname, (int) gid, strerror(errno));
 478                 goto fail;
 479         }
 480
 481         if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
 482                 wpa_printf(MSG_ERROR, "chmod[ctrl_interface=%s]: %s",
 483                            fname, strerror(errno));
 484                 goto fail;
 485         }
 486         os_free(fname);
 487
 488 #ifdef ANDROID
 489 havesock:
 490 #endif /* ANDROID */
 491
 492         /*
 493          * Make socket non-blocking so that we don't hang forever if
 494          * target dies unexpectedly.
 495          */
 496         flags = fcntl(priv->sock, F_GETFL);
 497         if (flags >= 0) {
 498                 flags |= O_NONBLOCK;
 499                 if (fcntl(priv->sock, F_SETFL, flags) < 0) {
 500                         wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
 501                                    strerror(errno));
 502                         /* Not fatal, continue on.*/
 503                 }
 504         }
 505
 506         eloop_register_read_sock(priv->sock, wpa_supplicant_ctrl_iface_receive,
 507                                  wpa_s, priv);
 508         wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
 509
 510         os_free(buf);
 511         return 0;
 512
 513 fail:
 514         if (priv->sock >= 0) {
 515                 close(priv->sock);
 516                 priv->sock = -1;
 517         }
 518         if (fname) {
 519                 unlink(fname);
 520                 os_free(fname);
 521         }
 522         os_free(buf);
 523         return -1;
 524 }
 525
 526
 527 struct ctrl_iface_priv *
 528 wpa_supplicant_ctrl_iface_init(struct wpa_supplicant *wpa_s)
 529 {
 530         struct ctrl_iface_priv *priv;
 531
 532         priv = os_zalloc(sizeof(*priv));
 533         if (priv == NULL)
 534                 return NULL;
 535         dl_list_init(&priv->ctrl_dst);
 536         priv->wpa_s = wpa_s;
 537         priv->sock = -1;
 538
 539         if (wpa_s->conf->ctrl_interface == NULL)
 540                 return priv;
 541
 542         if (wpas_ctrl_iface_open_sock(wpa_s, priv) < 0) {
 543                 os_free(priv);
 544                 return NULL;
 545         }
 546
 547         return priv;
 548 }
 549
 550
 551 static int wpas_ctrl_iface_reinit(struct wpa_supplicant *wpa_s,
 552                                   struct ctrl_iface_priv *priv)
 553 {
 554         int res;
 555
 556         if (priv->sock <= 0)
 557                 return -1;
 558
 559         eloop_unregister_read_sock(priv->sock);
 560         close(priv->sock);
 561         priv->sock = -1;
 562         res = wpas_ctrl_iface_open_sock(wpa_s, priv);
 563         if (res < 0)
 564                 return -1;
 565         return priv->sock;
 566 }
 567
 568
 569 void wpa_supplicant_ctrl_iface_deinit(struct ctrl_iface_priv *priv)
 570 {
 571         struct wpa_ctrl_dst *dst, *prev;
 572
 573         if (priv->sock > -1) {
 574                 char *fname;
 575                 char *buf, *dir = NULL;
 576                 eloop_unregister_read_sock(priv->sock);
 577                 if (!dl_list_empty(&priv->ctrl_dst)) {
 578                         /*
 579                          * Wait before closing the control socket if
 580                          * there are any attached monitors in order to allow
 581                          * them to receive any pending messages.
 582                          */
 583                         wpa_printf(MSG_DEBUG, "CTRL_IFACE wait for attached "
 584                                    "monitors to receive messages");
 585                         os_sleep(0, 100000);
 586                 }
 587                 close(priv->sock);
 588                 priv->sock = -1;
 589                 fname = wpa_supplicant_ctrl_iface_path(priv->wpa_s);
 590                 if (fname) {
 591                         unlink(fname);
 592                         os_free(fname);
 593                 }
 594
 595                 if (priv->wpa_s->conf->ctrl_interface == NULL)
 596                         goto free_dst;
 597                 buf = os_strdup(priv->wpa_s->conf->ctrl_interface);
 598                 if (buf == NULL)
 599                         goto free_dst;
 600                 if (os_strncmp(buf, "DIR=", 4) == 0) {
 601                         char *gid_str;
 602                         dir = buf + 4;
 603                         gid_str = os_strstr(dir, " GROUP=");
 604                         if (gid_str)
 605                                 *gid_str = '\0';
 606                 } else
 607                         dir = buf;
 608
 609                 if (rmdir(dir) < 0) {
 610                         if (errno == ENOTEMPTY) {
 611                                 wpa_printf(MSG_DEBUG, "Control interface "
 612                                            "directory not empty - leaving it "
 613                                            "behind");
 614                         } else {
 615                                 wpa_printf(MSG_ERROR,
 616                                            "rmdir[ctrl_interface=%s]: %s",
 617                                            dir, strerror(errno));
 618                         }
 619                 }
 620                 os_free(buf);
 621         }
 622
 623 free_dst:
 624         dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
 625                               list)
 626                 os_free(dst);
 627         os_free(priv);
 628 }
 629
 630
 631 /**
 632  * wpa_supplicant_ctrl_iface_send - Send a control interface packet to monitors
 633  * @ifname: Interface name for global control socket or %NULL
 634  * @sock: Local socket fd
 635  * @ctrl_dst: List of attached listeners
 636  * @level: Priority level of the message
 637  * @buf: Message data
 638  * @len: Message length
 639  *
 640  * Send a packet to all monitor programs attached to the control interface.
 641  */
 642 static void wpa_supplicant_ctrl_iface_send(struct wpa_supplicant *wpa_s,
 643                                            const char *ifname, int sock,
 644                                            struct dl_list *ctrl_dst,
 645                                            int level, const char *buf,
 646                                            size_t len,
 647                                            struct ctrl_iface_priv *priv,
 648                                            struct ctrl_iface_global_priv *gp)
 649 {
 650         struct wpa_ctrl_dst *dst, *next;
 651         char levelstr[10];
 652         int idx, res;
 653         struct msghdr msg;
 654         struct iovec io[5];
 655
 656         if (sock < 0 || dl_list_empty(ctrl_dst))
 657                 return;
 658
 659         res = os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);
 660         if (res < 0 || (size_t) res >= sizeof(levelstr))
 661                 return;
 662         idx = 0;
 663         if (ifname) {
 664                 io[idx].iov_base = "IFNAME=";
 665                 io[idx].iov_len = 7;
 666                 idx++;
 667                 io[idx].iov_base = (char *) ifname;
 668                 io[idx].iov_len = os_strlen(ifname);
 669                 idx++;
 670                 io[idx].iov_base = " ";
 671                 io[idx].iov_len = 1;
 672                 idx++;
 673         }
 674         io[idx].iov_base = levelstr;
 675         io[idx].iov_len = os_strlen(levelstr);
 676         idx++;
 677         io[idx].iov_base = (char *) buf;
 678         io[idx].iov_len = len;
 679         idx++;
 680         os_memset(&msg, 0, sizeof(msg));
 681         msg.msg_iov = io;
 682         msg.msg_iovlen = idx;
 683
 684         dl_list_for_each_safe(dst, next, ctrl_dst, struct wpa_ctrl_dst, list) {
 685                 int _errno;
 686                 char addr_txt[200];
 687
 688                 if (level < dst->debug_level)
 689                         continue;
 690
 691                 printf_encode(addr_txt, sizeof(addr_txt),
 692                               (u8 *) dst->addr.sun_path, dst->addrlen -
 693                               offsetof(struct sockaddr_un, sun_path));
 694                 msg.msg_name = (void *) &dst->addr;
 695                 msg.msg_namelen = dst->addrlen;
 696                 if (sendmsg(sock, &msg, MSG_DONTWAIT) >= 0) {
 697                         wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor sent successfully to %s",
 698                                    addr_txt);
 699                         dst->errors = 0;
 700                         continue;
 701                 }
 702
 703                 _errno = errno;
 704                 wpa_printf(MSG_DEBUG, "CTRL_IFACE monitor[%s]: %d - %s",
 705                            addr_txt, errno, strerror(errno));
 706                 dst->errors++;
 707
 708                 if (dst->errors > 10 || _errno == ENOENT || _errno == EPERM) {
 709                         wpa_printf(MSG_INFO, "CTRL_IFACE: Detach monitor %s that cannot receive messages",
 710                                 addr_txt);
 711                         wpa_supplicant_ctrl_iface_detach(ctrl_dst, &dst->addr,
 712                                                          dst->addrlen);
 713                 }
 714
 715                 if (_errno == ENOBUFS || _errno == EAGAIN) {
 716                         /*
 717                          * The socket send buffer could be full. This may happen
 718                          * if client programs are not receiving their pending
 719                          * messages. Close and reopen the socket as a workaround
 720                          * to avoid getting stuck being unable to send any new
 721                          * responses.
 722                          */
 723                         if (priv)
 724                                 sock = wpas_ctrl_iface_reinit(wpa_s, priv);
 725                         else if (gp)
 726                                 sock = wpas_ctrl_iface_global_reinit(
 727                                         wpa_s->global, gp);
 728                         else
 729                                 break;
 730                         if (sock < 0) {
 731                                 wpa_dbg(wpa_s, MSG_DEBUG,
 732                                         "Failed to reinitialize ctrl_iface socket");
 733                                 break;
 734                         }
 735                 }
 736         }
 737 }
 738
 739
 740 void wpa_supplicant_ctrl_iface_wait(struct ctrl_iface_priv *priv)
 741 {
 742         char buf[256];
 743         int res;
 744         struct sockaddr_un from;
 745         socklen_t fromlen = sizeof(from);
 746
 747         for (;;) {
 748                 wpa_printf(MSG_DEBUG, "CTRL_IFACE - %s - wait for monitor to "
 749                            "attach", priv->wpa_s->ifname);
 750                 eloop_wait_for_read_sock(priv->sock);
 751
 752                 res = recvfrom(priv->sock, buf, sizeof(buf) - 1, 0,
 753                                (struct sockaddr *) &from, &fromlen);
 754                 if (res < 0) {
 755                         wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 756                                    strerror(errno));
 757                         continue;
 758                 }
 759                 buf[res] = '\0';
 760
 761                 if (os_strcmp(buf, "ATTACH") == 0) {
 762                         /* handle ATTACH signal of first monitor interface */
 763                         if (!wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst,
 764                                                               &from, fromlen)) {
 765                                 if (sendto(priv->sock, "OK\n", 3, 0,
 766                                            (struct sockaddr *) &from, fromlen) <
 767                                     0) {
 768                                         wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
 769                                                    strerror(errno));
 770                                 }
 771                                 /* OK to continue */
 772                                 return;
 773                         } else {
 774                                 if (sendto(priv->sock, "FAIL\n", 5, 0,
 775                                            (struct sockaddr *) &from, fromlen) <
 776                                     0) {
 777                                         wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
 778                                                    strerror(errno));
 779                                 }
 780                         }
 781                 } else {
 782                         /* return FAIL for all other signals */
 783                         if (sendto(priv->sock, "FAIL\n", 5, 0,
 784                                    (struct sockaddr *) &from, fromlen) < 0) {
 785                                 wpa_printf(MSG_DEBUG,
 786                                            "ctrl_iface sendto failed: %s",
 787                                            strerror(errno));
 788                         }
 789                 }
 790         }
 791 }
 792
 793
 794 /* Global ctrl_iface */
 795
 796 static void wpa_supplicant_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 797                                                      void *sock_ctx)
 798 {
 799         struct wpa_global *global = eloop_ctx;
 800         struct ctrl_iface_global_priv *priv = sock_ctx;
 801         char buf[4096];
 802         int res;
 803         struct sockaddr_un from;
 804         socklen_t fromlen = sizeof(from);
 805         char *reply = NULL, *reply_buf = NULL;
 806         size_t reply_len;
 807
 808         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 809                        (struct sockaddr *) &from, &fromlen);
 810         if (res < 0) {
 811                 wpa_printf(MSG_ERROR, "recvfrom(ctrl_iface): %s",
 812                            strerror(errno));
 813                 return;
 814         }
 815         buf[res] = '\0';
 816
 817         if (os_strcmp(buf, "ATTACH") == 0) {
 818                 if (wpa_supplicant_ctrl_iface_attach(&priv->ctrl_dst, &from,
 819                                                      fromlen))
 820                         reply_len = 1;
 821                 else
 822                         reply_len = 2;
 823         } else if (os_strcmp(buf, "DETACH") == 0) {
 824                 if (wpa_supplicant_ctrl_iface_detach(&priv->ctrl_dst, &from,
 825                                                      fromlen))
 826                         reply_len = 1;
 827                 else
 828                         reply_len = 2;
 829         } else {
 830                 reply_buf = wpa_supplicant_global_ctrl_iface_process(
 831                         global, buf, &reply_len);
 832                 reply = reply_buf;
 833         }
 834
 835         if (!reply && reply_len == 1) {
 836                 reply = "FAIL\n";
 837                 reply_len = 5;
 838         } else if (!reply && reply_len == 2) {
 839                 reply = "OK\n";
 840                 reply_len = 3;
 841         }
 842
 843         if (reply) {
 844                 if (sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 845                            fromlen) < 0) {
 846                         wpa_printf(MSG_DEBUG, "ctrl_iface sendto failed: %s",
 847                                 strerror(errno));
 848                 }
 849         }
 850         os_free(reply_buf);
 851 }
 852
 853
 854 static int wpas_global_ctrl_iface_open_sock(struct wpa_global *global,
 855                                             struct ctrl_iface_global_priv *priv)
 856 {
 857         struct sockaddr_un addr;
 858         const char *ctrl = global->params.ctrl_interface;
 859         int flags;
 860
 861         wpa_printf(MSG_DEBUG, "Global control interface '%s'", ctrl);
 862
 863 #ifdef ANDROID
 864         if (os_strncmp(ctrl, "@android:", 9) == 0) {
 865                 priv->sock = android_get_control_socket(ctrl + 9);
 866                 if (priv->sock < 0) {
 867                         wpa_printf(MSG_ERROR, "Failed to open Android control "
 868                                    "socket '%s'", ctrl + 9);
 869                         goto fail;
 870                 }
 871                 wpa_printf(MSG_DEBUG, "Using Android control socket '%s'",
 872                            ctrl + 9);
 873                 goto havesock;
 874         }
 875
 876         if (os_strncmp(ctrl, "@abstract:", 10) != 0) {
 877                 /*
 878                  * Backwards compatibility - try to open an Android control
 879                  * socket and if that fails, assume this was a UNIX domain
 880                  * socket instead.
 881                  */
 882                 priv->sock = android_get_control_socket(ctrl);
 883                 if (priv->sock >= 0) {
 884                         wpa_printf(MSG_DEBUG,
 885                                    "Using Android control socket '%s'",
 886                                    ctrl);
 887                         goto havesock;
 888                 }
 889         }
 890 #endif /* ANDROID */
 891
 892         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 893         if (priv->sock < 0) {
 894                 wpa_printf(MSG_ERROR, "socket(PF_UNIX): %s", strerror(errno));
 895                 goto fail;
 896         }
 897
 898         os_memset(&addr, 0, sizeof(addr));
 899 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 900         addr.sun_len = sizeof(addr);
 901 #endif /* __FreeBSD__ */
 902         addr.sun_family = AF_UNIX;
 903
 904         if (os_strncmp(ctrl, "@abstract:", 10) == 0) {
 905                 addr.sun_path[0] = '\0';
 906                 os_strlcpy(addr.sun_path + 1, ctrl + 10,
 907                            sizeof(addr.sun_path) - 1);
 908                 if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) <
 909                     0) {
 910                         wpa_printf(MSG_ERROR, "supp-global-ctrl-iface-init: "
 911                                    "bind(PF_UNIX;%s) failed: %s",
 912                                    ctrl, strerror(errno));
 913                         goto fail;
 914                 }
 915                 wpa_printf(MSG_DEBUG, "Using Abstract control socket '%s'",
 916                            ctrl + 10);
 917                 goto havesock;
 918         }
 919
 920         os_strlcpy(addr.sun_path, ctrl, sizeof(addr.sun_path));
 921         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 922                 wpa_printf(MSG_INFO, "supp-global-ctrl-iface-init(%s) (will try fixup): bind(PF_UNIX): %s",
 923                            ctrl, strerror(errno));
 924                 if (connect(priv->sock, (struct sockaddr *) &addr,
 925                             sizeof(addr)) < 0) {
 926                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 927                                    " allow connections - assuming it was left"
 928                                    "over from forced program termination");
 929                         if (unlink(ctrl) < 0) {
 930                                 wpa_printf(MSG_ERROR,
 931                                            "Could not unlink existing ctrl_iface socket '%s': %s",
 932                                            ctrl, strerror(errno));
 933                                 goto fail;
 934                         }
 935                         if (bind(priv->sock, (struct sockaddr *) &addr,
 936                                  sizeof(addr)) < 0) {
 937                                 wpa_printf(MSG_ERROR, "supp-glb-iface-init: bind(PF_UNIX;%s): %s",
 938                                            ctrl, strerror(errno));
 939                                 goto fail;
 940                         }
 941                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 942                                    "ctrl_iface socket '%s'",
 943                                    ctrl);
 944                 } else {
 945                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 946                                    "be in use - cannot override it");
 947                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 948                                    "not used anymore",
 949                                    ctrl);
 950                         goto fail;
 951                 }
 952         }
 953
 954         wpa_printf(MSG_DEBUG, "Using UNIX control socket '%s'", ctrl);
 955
 956         if (global->params.ctrl_interface_group) {
 957                 char *gid_str = global->params.ctrl_interface_group;
 958                 gid_t gid = 0;
 959                 struct group *grp;
 960                 char *endp;
 961
 962                 grp = getgrnam(gid_str);
 963                 if (grp) {
 964                         gid = grp->gr_gid;
 965                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 966                                    " (from group name '%s')",
 967                                    (int) gid, gid_str);
 968                 } else {
 969                         /* Group name not found - try to parse this as gid */
 970                         gid = strtol(gid_str, &endp, 10);
 971                         if (*gid_str == '\0' || *endp != '\0') {
 972                                 wpa_printf(MSG_ERROR, "CTRL: Invalid group "
 973                                            "'%s'", gid_str);
 974                                 goto fail;
 975                         }
 976                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 977                                    (int) gid);
 978                 }
 979                 if (chown(ctrl, -1, gid) < 0) {
 980                         wpa_printf(MSG_ERROR,
 981                                    "chown[global_ctrl_interface=%s,gid=%d]: %s",
 982                                    ctrl, (int) gid, strerror(errno));
 983                         goto fail;
 984                 }
 985
 986                 if (chmod(ctrl, S_IRWXU | S_IRWXG) < 0) {
 987                         wpa_printf(MSG_ERROR,
 988                                    "chmod[global_ctrl_interface=%s]: %s",
 989                                    ctrl, strerror(errno));
 990                         goto fail;
 991                 }
 992         } else {
 993                 if (chmod(ctrl, S_IRWXU) < 0) {
 994                         wpa_printf(MSG_DEBUG,
 995                                    "chmod[global_ctrl_interface=%s](S_IRWXU): %s",
 996                                    ctrl, strerror(errno));
 997                         /* continue anyway since group change was not required
 998                          */
 999                 }
1000         }
1001
1002 havesock:
1003
1004         /*
1005          * Make socket non-blocking so that we don't hang forever if
1006          * target dies unexpectedly.
1007          */
1008         flags = fcntl(priv->sock, F_GETFL);
1009         if (flags >= 0) {
1010                 flags |= O_NONBLOCK;
1011                 if (fcntl(priv->sock, F_SETFL, flags) < 0) {
1012                         wpa_printf(MSG_INFO, "fcntl(ctrl, O_NONBLOCK): %s",
1013                                    strerror(errno));
1014                         /* Not fatal, continue on.*/
1015                 }
1016         }
1017
1018         eloop_register_read_sock(priv->sock,
1019                                  wpa_supplicant_global_ctrl_iface_receive,
1020                                  global, priv);
1021
1022         return 0;
1023
1024 fail:
1025         if (priv->sock >= 0) {
1026                 close(priv->sock);
1027                 priv->sock = -1;
1028         }
1029         return -1;
1030 }
1031
1032
1033 struct ctrl_iface_global_priv *
1034 wpa_supplicant_global_ctrl_iface_init(struct wpa_global *global)
1035 {
1036         struct ctrl_iface_global_priv *priv;
1037
1038         priv = os_zalloc(sizeof(*priv));
1039         if (priv == NULL)
1040                 return NULL;
1041         dl_list_init(&priv->ctrl_dst);
1042         priv->global = global;
1043         priv->sock = -1;
1044
1045         if (global->params.ctrl_interface == NULL)
1046                 return priv;
1047
1048         if (wpas_global_ctrl_iface_open_sock(global, priv) < 0) {
1049                 os_free(priv);
1050                 return NULL;
1051         }
1052
1053         wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
1054
1055         return priv;
1056 }
1057
1058
1059 static int wpas_ctrl_iface_global_reinit(struct wpa_global *global,
1060                                          struct ctrl_iface_global_priv *priv)
1061 {
1062         int res;
1063
1064         if (priv->sock <= 0)
1065                 return -1;
1066
1067         eloop_unregister_read_sock(priv->sock);
1068         close(priv->sock);
1069         priv->sock = -1;
1070         res = wpas_global_ctrl_iface_open_sock(global, priv);
1071         if (res < 0)
1072                 return -1;
1073         return priv->sock;
1074 }
1075
1076
1077 void
1078 wpa_supplicant_global_ctrl_iface_deinit(struct ctrl_iface_global_priv *priv)
1079 {
1080         struct wpa_ctrl_dst *dst, *prev;
1081
1082         if (priv->sock >= 0) {
1083                 eloop_unregister_read_sock(priv->sock);
1084                 close(priv->sock);
1085         }
1086         if (priv->global->params.ctrl_interface)
1087                 unlink(priv->global->params.ctrl_interface);
1088         dl_list_for_each_safe(dst, prev, &priv->ctrl_dst, struct wpa_ctrl_dst,
1089                               list)
1090                 os_free(dst);
1091         os_free(priv);
1092 }