contrib/wpa_supplicant-0.5.8/ctrl_iface_unix.c

   1 /*
   2  * WPA Supplicant / UNIX domain socket -based control interface
   3  * Copyright (c) 2004-2005, Jouni Malinen <j@w1.fi>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * Alternatively, this software may be distributed under the terms of BSD
  10  * license.
  11  *
  12  * See README and COPYING for more details.
  13  */
  14
  15 #include "includes.h"
  16 #include <sys/un.h>
  17 #include <sys/stat.h>
  18 #include <grp.h>
  19
  20 #include "common.h"
  21 #include "eloop.h"
  22 #include "config.h"
  23 #include "eapol_sm.h"
  24 #include "wpa_supplicant_i.h"
  25 #include "ctrl_iface.h"
  26
  27 /* Per-interface ctrl_iface */
  28
  29 /**
  30  * struct wpa_ctrl_dst - Internal data structure of control interface monitors
  31  *
  32  * This structure is used to store information about registered control
  33  * interface monitors into struct wpa_supplicant. This data is private to
  34  * ctrl_iface_unix.c and should not be touched directly from other files.
  35  */
  36 struct wpa_ctrl_dst {
  37         struct wpa_ctrl_dst *next;
  38         struct sockaddr_un addr;
  39         socklen_t addrlen;
  40         int debug_level;
  41         int errors;
  42 };
  43
  44
  45 struct ctrl_iface_priv {
  46         struct wpa_supplicant *wpa_s;
  47         int sock;
  48         struct wpa_ctrl_dst *ctrl_dst;
  49 };
  50
  51
  52 static void wpa_supplicant_ctrl_iface_send(struct ctrl_iface_priv *priv,
  53                                            int level, const char *buf,
  54                                            size_t len);
  55
  56
  57 static int wpa_supplicant_ctrl_iface_attach(struct ctrl_iface_priv *priv,
  58                                             struct sockaddr_un *from,
  59                                             socklen_t fromlen)
  60 {
  61         struct wpa_ctrl_dst *dst;
  62
  63         dst = os_zalloc(sizeof(*dst));
  64         if (dst == NULL)
  65                 return -1;
  66         os_memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
  67         dst->addrlen = fromlen;
  68         dst->debug_level = MSG_INFO;
  69         dst->next = priv->ctrl_dst;
  70         priv->ctrl_dst = dst;
  71         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor attached",
  72                     (u8 *) from->sun_path, fromlen - sizeof(from->sun_family));
  73         return 0;
  74 }
  75
  76
  77 static int wpa_supplicant_ctrl_iface_detach(struct ctrl_iface_priv *priv,
  78                                             struct sockaddr_un *from,
  79                                             socklen_t fromlen)
  80 {
  81         struct wpa_ctrl_dst *dst, *prev = NULL;
  82
  83         dst = priv->ctrl_dst;
  84         while (dst) {
  85                 if (fromlen == dst->addrlen &&
  86                     os_memcmp(from->sun_path, dst->addr.sun_path,
  87                               fromlen - sizeof(from->sun_family)) == 0) {
  88                         if (prev == NULL)
  89                                 priv->ctrl_dst = dst->next;
  90                         else
  91                                 prev->next = dst->next;
  92                         os_free(dst);
  93                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor detached",
  94                                     (u8 *) from->sun_path,
  95                                     fromlen - sizeof(from->sun_family));
  96                         return 0;
  97                 }
  98                 prev = dst;
  99                 dst = dst->next;
 100         }
 101         return -1;
 102 }
 103
 104
 105 static int wpa_supplicant_ctrl_iface_level(struct ctrl_iface_priv *priv,
 106                                            struct sockaddr_un *from,
 107                                            socklen_t fromlen,
 108                                            char *level)
 109 {
 110         struct wpa_ctrl_dst *dst;
 111
 112         wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", level);
 113
 114         dst = priv->ctrl_dst;
 115         while (dst) {
 116                 if (fromlen == dst->addrlen &&
 117                     os_memcmp(from->sun_path, dst->addr.sun_path,
 118                               fromlen - sizeof(from->sun_family)) == 0) {
 119                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE changed monitor "
 120                                     "level", (u8 *) from->sun_path,
 121                                     fromlen - sizeof(from->sun_family));
 122                         dst->debug_level = atoi(level);
 123                         return 0;
 124                 }
 125                 dst = dst->next;
 126         }
 127
 128         return -1;
 129 }
 130
 131
 132 static void wpa_supplicant_ctrl_iface_receive(int sock, void *eloop_ctx,
 133                                               void *sock_ctx)
 134 {
 135         struct wpa_supplicant *wpa_s = eloop_ctx;
 136         struct ctrl_iface_priv *priv = sock_ctx;
 137         char buf[256];
 138         int res;
 139         struct sockaddr_un from;
 140         socklen_t fromlen = sizeof(from);
 141         char *reply = NULL;
 142         size_t reply_len = 0;
 143         int new_attached = 0;
 144
 145         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 146                        (struct sockaddr *) &from, &fromlen);
 147         if (res < 0) {
 148                 perror("recvfrom(ctrl_iface)");
 149                 return;
 150         }
 151         buf[res] = '\0';
 152
 153         if (os_strcmp(buf, "ATTACH") == 0) {
 154                 if (wpa_supplicant_ctrl_iface_attach(priv, &from, fromlen))
 155                         reply_len = 1;
 156                 else {
 157                         new_attached = 1;
 158                         reply_len = 2;
 159                 }
 160         } else if (os_strcmp(buf, "DETACH") == 0) {
 161                 if (wpa_supplicant_ctrl_iface_detach(priv, &from, fromlen))
 162                         reply_len = 1;
 163                 else
 164                         reply_len = 2;
 165         } else if (os_strncmp(buf, "LEVEL ", 6) == 0) {
 166                 if (wpa_supplicant_ctrl_iface_level(priv, &from, fromlen,
 167                                                     buf + 6))
 168                         reply_len = 1;
 169                 else
 170                         reply_len = 2;
 171         } else {
 172                 reply = wpa_supplicant_ctrl_iface_process(wpa_s, buf,
 173                                                           &reply_len);
 174         }
 175
 176         if (reply) {
 177                 sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 178                        fromlen);
 179                 os_free(reply);
 180         } else if (reply_len == 1) {
 181                 sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
 182                        fromlen);
 183         } else if (reply_len == 2) {
 184                 sendto(sock, "OK\n", 3, 0, (struct sockaddr *) &from,
 185                        fromlen);
 186         }
 187
 188         if (new_attached)
 189                 eapol_sm_notify_ctrl_attached(wpa_s->eapol);
 190 }
 191
 192
 193 static char * wpa_supplicant_ctrl_iface_path(struct wpa_supplicant *wpa_s)
 194 {
 195         char *buf;
 196         size_t len;
 197         char *pbuf, *dir = NULL, *gid_str = NULL;
 198
 199         if (wpa_s->conf->ctrl_interface == NULL)
 200                 return NULL;
 201
 202         pbuf = os_strdup(wpa_s->conf->ctrl_interface);
 203         if (pbuf == NULL)
 204                 return NULL;
 205         if (os_strncmp(pbuf, "DIR=", 4) == 0) {
 206                 dir = pbuf + 4;
 207                 gid_str = os_strstr(dir, " GROUP=");
 208                 if (gid_str) {
 209                         *gid_str = '\0';
 210                         gid_str += 7;
 211                 }
 212         } else
 213                 dir = pbuf;
 214
 215         len = os_strlen(dir) + os_strlen(wpa_s->ifname) + 2;
 216         buf = os_malloc(len);
 217         if (buf == NULL) {
 218                 os_free(pbuf);
 219                 return NULL;
 220         }
 221
 222         os_snprintf(buf, len, "%s/%s", dir, wpa_s->ifname);
 223 #ifdef __CYGWIN__
 224         {
 225                 /* Windows/WinPcap uses interface names that are not suitable
 226                  * as a file name - convert invalid chars to underscores */
 227                 char *pos = buf;
 228                 while (*pos) {
 229                         if (*pos == '\\')
 230                                 *pos = '_';
 231                         pos++;
 232                 }
 233         }
 234 #endif /* __CYGWIN__ */
 235         os_free(pbuf);
 236         return buf;
 237 }
 238
 239
 240 static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level,
 241                                              const char *txt, size_t len)
 242 {
 243         struct wpa_supplicant *wpa_s = ctx;
 244         if (wpa_s == NULL || wpa_s->ctrl_iface == NULL)
 245                 return;
 246         wpa_supplicant_ctrl_iface_send(wpa_s->ctrl_iface, level, txt, len);
 247 }
 248
 249
 250 struct ctrl_iface_priv *
 251 wpa_supplicant_ctrl_iface_init(struct wpa_supplicant *wpa_s)
 252 {
 253         struct ctrl_iface_priv *priv;
 254         struct sockaddr_un addr;
 255         char *fname = NULL;
 256         gid_t gid = 0;
 257         int gid_set = 0;
 258         char *buf, *dir = NULL, *gid_str = NULL;
 259         struct group *grp;
 260         char *endp;
 261
 262         priv = os_zalloc(sizeof(*priv));
 263         if (priv == NULL)
 264                 return NULL;
 265         priv->wpa_s = wpa_s;
 266         priv->sock = -1;
 267
 268         if (wpa_s->conf->ctrl_interface == NULL)
 269                 return priv;
 270
 271         buf = os_strdup(wpa_s->conf->ctrl_interface);
 272         if (buf == NULL)
 273                 goto fail;
 274         if (os_strncmp(buf, "DIR=", 4) == 0) {
 275                 dir = buf + 4;
 276                 gid_str = os_strstr(dir, " GROUP=");
 277                 if (gid_str) {
 278                         *gid_str = '\0';
 279                         gid_str += 7;
 280                 }
 281         } else {
 282                 dir = buf;
 283                 gid_str = wpa_s->conf->ctrl_interface_group;
 284         }
 285
 286         if (mkdir(dir, S_IRWXU | S_IRWXG) < 0) {
 287                 if (errno == EEXIST) {
 288                         wpa_printf(MSG_DEBUG, "Using existing control "
 289                                    "interface directory.");
 290                 } else {
 291                         perror("mkdir[ctrl_interface]");
 292                         goto fail;
 293                 }
 294         }
 295
 296         if (gid_str) {
 297                 grp = getgrnam(gid_str);
 298                 if (grp) {
 299                         gid = grp->gr_gid;
 300                         gid_set = 1;
 301                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d"
 302                                    " (from group name '%s')",
 303                                    (int) gid, gid_str);
 304                 } else {
 305                         /* Group name not found - try to parse this as gid */
 306                         gid = strtol(gid_str, &endp, 10);
 307                         if (*gid_str == '\0' || *endp != '\0') {
 308                                 wpa_printf(MSG_DEBUG, "CTRL: Invalid group "
 309                                            "'%s'", gid_str);
 310                                 goto fail;
 311                         }
 312                         gid_set = 1;
 313                         wpa_printf(MSG_DEBUG, "ctrl_interface_group=%d",
 314                                    (int) gid);
 315                 }
 316         }
 317
 318         if (gid_set && chown(dir, -1, gid) < 0) {
 319                 perror("chown[ctrl_interface]");
 320                 goto fail;
 321         }
 322
 323         if (os_strlen(dir) + 1 + os_strlen(wpa_s->ifname) >=
 324             sizeof(addr.sun_path))
 325                 goto fail;
 326
 327         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 328         if (priv->sock < 0) {
 329                 perror("socket(PF_UNIX)");
 330                 goto fail;
 331         }
 332
 333         os_memset(&addr, 0, sizeof(addr));
 334         addr.sun_family = AF_UNIX;
 335         fname = wpa_supplicant_ctrl_iface_path(wpa_s);
 336         if (fname == NULL)
 337                 goto fail;
 338         os_strncpy(addr.sun_path, fname, sizeof(addr.sun_path));
 339         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 340                 wpa_printf(MSG_DEBUG, "ctrl_iface bind(PF_UNIX) failed: %s",
 341                            strerror(errno));
 342                 if (connect(priv->sock, (struct sockaddr *) &addr,
 343                             sizeof(addr)) < 0) {
 344                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 345                                    " allow connections - assuming it was left"
 346                                    "over from forced program termination");
 347                         if (unlink(fname) < 0) {
 348                                 perror("unlink[ctrl_iface]");
 349                                 wpa_printf(MSG_ERROR, "Could not unlink "
 350                                            "existing ctrl_iface socket '%s'",
 351                                            fname);
 352                                 goto fail;
 353                         }
 354                         if (bind(priv->sock, (struct sockaddr *) &addr,
 355                                  sizeof(addr)) < 0) {
 356                                 perror("bind(PF_UNIX)");
 357                                 goto fail;
 358                         }
 359                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 360                                    "ctrl_iface socket '%s'", fname);
 361                 } else {
 362                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 363                                    "be in use - cannot override it");
 364                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 365                                    "not used anymore", fname);
 366                         os_free(fname);
 367                         fname = NULL;
 368                         goto fail;
 369                 }
 370         }
 371
 372         if (gid_set && chown(fname, -1, gid) < 0) {
 373                 perror("chown[ctrl_interface/ifname]");
 374                 goto fail;
 375         }
 376
 377         if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
 378                 perror("chmod[ctrl_interface/ifname]");
 379                 goto fail;
 380         }
 381         os_free(fname);
 382
 383         eloop_register_read_sock(priv->sock, wpa_supplicant_ctrl_iface_receive,
 384                                  wpa_s, priv);
 385         wpa_msg_register_cb(wpa_supplicant_ctrl_iface_msg_cb);
 386
 387         os_free(buf);
 388         return priv;
 389
 390 fail:
 391         if (priv->sock >= 0)
 392                 close(priv->sock);
 393         os_free(priv);
 394         if (fname) {
 395                 unlink(fname);
 396                 os_free(fname);
 397         }
 398         os_free(buf);
 399         return NULL;
 400 }
 401
 402
 403 void wpa_supplicant_ctrl_iface_deinit(struct ctrl_iface_priv *priv)
 404 {
 405         struct wpa_ctrl_dst *dst, *prev;
 406
 407         if (priv->sock > -1) {
 408                 char *fname;
 409                 char *buf, *dir = NULL, *gid_str = NULL;
 410                 eloop_unregister_read_sock(priv->sock);
 411                 if (priv->ctrl_dst) {
 412                         /*
 413                          * Wait a second before closing the control socket if
 414                          * there are any attached monitors in order to allow
 415                          * them to receive any pending messages.
 416                          */
 417                         wpa_printf(MSG_DEBUG, "CTRL_IFACE wait for attached "
 418                                    "monitors to receive messages");
 419                         os_sleep(1, 0);
 420                 }
 421                 close(priv->sock);
 422                 priv->sock = -1;
 423                 fname = wpa_supplicant_ctrl_iface_path(priv->wpa_s);
 424                 if (fname) {
 425                         unlink(fname);
 426                         os_free(fname);
 427                 }
 428
 429                 buf = os_strdup(priv->wpa_s->conf->ctrl_interface);
 430                 if (buf == NULL)
 431                         goto free_dst;
 432                 if (os_strncmp(buf, "DIR=", 4) == 0) {
 433                         dir = buf + 4;
 434                         gid_str = os_strstr(dir, " GROUP=");
 435                         if (gid_str) {
 436                                 *gid_str = '\0';
 437                                 gid_str += 7;
 438                         }
 439                 } else
 440                         dir = buf;
 441
 442                 if (rmdir(dir) < 0) {
 443                         if (errno == ENOTEMPTY) {
 444                                 wpa_printf(MSG_DEBUG, "Control interface "
 445                                            "directory not empty - leaving it "
 446                                            "behind");
 447                         } else {
 448                                 perror("rmdir[ctrl_interface]");
 449                         }
 450                 }
 451                 os_free(buf);
 452         }
 453
 454 free_dst:
 455         dst = priv->ctrl_dst;
 456         while (dst) {
 457                 prev = dst;
 458                 dst = dst->next;
 459                 os_free(prev);
 460         }
 461         os_free(priv);
 462 }
 463
 464
 465 /**
 466  * wpa_supplicant_ctrl_iface_send - Send a control interface packet to monitors
 467  * @priv: Pointer to private data from wpa_supplicant_ctrl_iface_init()
 468  * @level: Priority level of the message
 469  * @buf: Message data
 470  * @len: Message length
 471  *
 472  * Send a packet to all monitor programs attached to the control interface.
 473  */
 474 static void wpa_supplicant_ctrl_iface_send(struct ctrl_iface_priv *priv,
 475                                            int level, const char *buf,
 476                                            size_t len)
 477 {
 478         struct wpa_ctrl_dst *dst, *next;
 479         char levelstr[10];
 480         int idx;
 481         struct msghdr msg;
 482         struct iovec io[2];
 483
 484         dst = priv->ctrl_dst;
 485         if (priv->sock < 0 || dst == NULL)
 486                 return;
 487
 488         os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);
 489         io[0].iov_base = levelstr;
 490         io[0].iov_len = os_strlen(levelstr);
 491         io[1].iov_base = (char *) buf;
 492         io[1].iov_len = len;
 493         os_memset(&msg, 0, sizeof(msg));
 494         msg.msg_iov = io;
 495         msg.msg_iovlen = 2;
 496
 497         idx = 0;
 498         while (dst) {
 499                 next = dst->next;
 500                 if (level >= dst->debug_level) {
 501                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor send",
 502                                     (u8 *) dst->addr.sun_path, dst->addrlen -
 503                                     sizeof(dst->addr.sun_family));
 504                         msg.msg_name = (void *) &dst->addr;
 505                         msg.msg_namelen = dst->addrlen;
 506                         if (sendmsg(priv->sock, &msg, 0) < 0) {
 507                                 perror("sendmsg(CTRL_IFACE monitor)");
 508                                 dst->errors++;
 509                                 if (dst->errors > 10) {
 510                                         wpa_supplicant_ctrl_iface_detach(
 511                                                 priv, &dst->addr,
 512                                                 dst->addrlen);
 513                                 }
 514                         } else
 515                                 dst->errors = 0;
 516                 }
 517                 idx++;
 518                 dst = next;
 519         }
 520 }
 521
 522
 523 void wpa_supplicant_ctrl_iface_wait(struct ctrl_iface_priv *priv)
 524 {
 525         wpa_printf(MSG_DEBUG, "CTRL_IFACE - %s - wait for monitor",
 526                    priv->wpa_s->ifname);
 527         eloop_wait_for_read_sock(priv->sock);
 528 }
 529
 530
 531 /* Global ctrl_iface */
 532
 533 struct ctrl_iface_global_priv {
 534         struct wpa_global *global;
 535         int sock;
 536 };
 537
 538
 539 static void wpa_supplicant_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 540                                                      void *sock_ctx)
 541 {
 542         struct wpa_global *global = eloop_ctx;
 543         char buf[256];
 544         int res;
 545         struct sockaddr_un from;
 546         socklen_t fromlen = sizeof(from);
 547         char *reply;
 548         size_t reply_len;
 549
 550         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 551                        (struct sockaddr *) &from, &fromlen);
 552         if (res < 0) {
 553                 perror("recvfrom(ctrl_iface)");
 554                 return;
 555         }
 556         buf[res] = '\0';
 557
 558         reply = wpa_supplicant_global_ctrl_iface_process(global, buf,
 559                                                          &reply_len);
 560
 561         if (reply) {
 562                 sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from,
 563                        fromlen);
 564                 os_free(reply);
 565         } else if (reply_len) {
 566                 sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
 567                        fromlen);
 568         }
 569 }
 570
 571
 572 struct ctrl_iface_global_priv *
 573 wpa_supplicant_global_ctrl_iface_init(struct wpa_global *global)
 574 {
 575         struct ctrl_iface_global_priv *priv;
 576         struct sockaddr_un addr;
 577
 578         priv = os_zalloc(sizeof(*priv));
 579         if (priv == NULL)
 580                 return NULL;
 581         priv->global = global;
 582         priv->sock = -1;
 583
 584         if (global->params.ctrl_interface == NULL)
 585                 return priv;
 586
 587         wpa_printf(MSG_DEBUG, "Global control interface '%s'",
 588                    global->params.ctrl_interface);
 589
 590         priv->sock = socket(PF_UNIX, SOCK_DGRAM, 0);
 591         if (priv->sock < 0) {
 592                 perror("socket(PF_UNIX)");
 593                 goto fail;
 594         }
 595
 596         os_memset(&addr, 0, sizeof(addr));
 597         addr.sun_family = AF_UNIX;
 598         os_strncpy(addr.sun_path, global->params.ctrl_interface,
 599                    sizeof(addr.sun_path));
 600         if (bind(priv->sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 601                 perror("bind(PF_UNIX)");
 602                 if (connect(priv->sock, (struct sockaddr *) &addr,
 603                             sizeof(addr)) < 0) {
 604                         wpa_printf(MSG_DEBUG, "ctrl_iface exists, but does not"
 605                                    " allow connections - assuming it was left"
 606                                    "over from forced program termination");
 607                         if (unlink(global->params.ctrl_interface) < 0) {
 608                                 perror("unlink[ctrl_iface]");
 609                                 wpa_printf(MSG_ERROR, "Could not unlink "
 610                                            "existing ctrl_iface socket '%s'",
 611                                            global->params.ctrl_interface);
 612                                 goto fail;
 613                         }
 614                         if (bind(priv->sock, (struct sockaddr *) &addr,
 615                                  sizeof(addr)) < 0) {
 616                                 perror("bind(PF_UNIX)");
 617                                 goto fail;
 618                         }
 619                         wpa_printf(MSG_DEBUG, "Successfully replaced leftover "
 620                                    "ctrl_iface socket '%s'",
 621                                    global->params.ctrl_interface);
 622                 } else {
 623                         wpa_printf(MSG_INFO, "ctrl_iface exists and seems to "
 624                                    "be in use - cannot override it");
 625                         wpa_printf(MSG_INFO, "Delete '%s' manually if it is "
 626                                    "not used anymore",
 627                                    global->params.ctrl_interface);
 628                         goto fail;
 629                 }
 630         }
 631
 632         eloop_register_read_sock(priv->sock,
 633                                  wpa_supplicant_global_ctrl_iface_receive,
 634                                  global, NULL);
 635
 636         return priv;
 637
 638 fail:
 639         if (priv->sock >= 0)
 640                 close(priv->sock);
 641         os_free(priv);
 642         return NULL;
 643 }
 644
 645
 646 void
 647 wpa_supplicant_global_ctrl_iface_deinit(struct ctrl_iface_global_priv *priv)
 648 {
 649         if (priv->sock >= 0) {
 650                 eloop_unregister_read_sock(priv->sock);
 651                 close(priv->sock);
 652         }
 653         if (priv->global->params.ctrl_interface)
 654                 unlink(priv->global->params.ctrl_interface);
 655         os_free(priv);
 656 }