contrib/hostapd/ctrl_iface.c

   1 /*
   2  * Host AP (software wireless LAN access point) user space daemon for
   3  * Host AP kernel driver / UNIX domain socket -based control interface
   4  * Copyright (c) 2004, Jouni Malinen <jkmaline@cc.hut.fi>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Alternatively, this software may be distributed under the terms of BSD
  11  * license.
  12  *
  13  * See README and COPYING for more details.
  14  */
  15
  16 #include <stdlib.h>
  17 #include <stdio.h>
  18 #include <string.h>
  19 #include <unistd.h>
  20 #include <sys/types.h>
  21 #include <sys/socket.h>
  22 #include <sys/un.h>
  23 #include <sys/uio.h>
  24 #include <sys/stat.h>
  25 #include <errno.h>
  26 #include <netinet/in.h>
  27
  28 #include "hostapd.h"
  29 #include "eloop.h"
  30 #include "config.h"
  31 #include "eapol_sm.h"
  32 #include "ieee802_1x.h"
  33 #include "wpa.h"
  34 #include "radius_client.h"
  35 #include "ieee802_11.h"
  36 #include "ctrl_iface.h"
  37 #include "sta_info.h"
  38
  39
  40 struct wpa_ctrl_dst {
  41         struct wpa_ctrl_dst *next;
  42         struct sockaddr_un addr;
  43         socklen_t addrlen;
  44         int debug_level;
  45         int errors;
  46 };
  47
  48
  49 static int hostapd_ctrl_iface_attach(struct hostapd_data *hapd,
  50                                      struct sockaddr_un *from,
  51                                      socklen_t fromlen)
  52 {
  53         struct wpa_ctrl_dst *dst;
  54
  55         dst = malloc(sizeof(*dst));
  56         if (dst == NULL)
  57                 return -1;
  58         memset(dst, 0, sizeof(*dst));
  59         memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
  60         dst->addrlen = fromlen;
  61         dst->debug_level = MSG_INFO;
  62         dst->next = hapd->ctrl_dst;
  63         hapd->ctrl_dst = dst;
  64         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor attached",
  65                     (u8 *) from->sun_path, fromlen);
  66         return 0;
  67 }
  68
  69
  70 static int hostapd_ctrl_iface_detach(struct hostapd_data *hapd,
  71                                      struct sockaddr_un *from,
  72                                      socklen_t fromlen)
  73 {
  74         struct wpa_ctrl_dst *dst, *prev = NULL;
  75
  76         dst = hapd->ctrl_dst;
  77         while (dst) {
  78                 if (fromlen == dst->addrlen &&
  79                     memcmp(from->sun_path, dst->addr.sun_path, fromlen) == 0) {
  80                         if (prev == NULL)
  81                                 hapd->ctrl_dst = dst->next;
  82                         else
  83                                 prev->next = dst->next;
  84                         free(dst);
  85                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor detached",
  86                                     (u8 *) from->sun_path, fromlen);
  87                         return 0;
  88                 }
  89                 prev = dst;
  90                 dst = dst->next;
  91         }
  92         return -1;
  93 }
  94
  95
  96 static int hostapd_ctrl_iface_level(struct hostapd_data *hapd,
  97                                     struct sockaddr_un *from,
  98                                     socklen_t fromlen,
  99                                     char *level)
 100 {
 101         struct wpa_ctrl_dst *dst;
 102
 103         wpa_printf(MSG_DEBUG, "CTRL_IFACE LEVEL %s", level);
 104
 105         dst = hapd->ctrl_dst;
 106         while (dst) {
 107                 if (fromlen == dst->addrlen &&
 108                     memcmp(from->sun_path, dst->addr.sun_path, fromlen) == 0) {
 109                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE changed monitor "
 110                                     "level", (u8 *) from->sun_path, fromlen);
 111                         dst->debug_level = atoi(level);
 112                         return 0;
 113                 }
 114                 dst = dst->next;
 115         }
 116
 117         return -1;
 118 }
 119
 120
 121 static int hostapd_ctrl_iface_sta_mib(struct hostapd_data *hapd,
 122                                       struct sta_info *sta,
 123                                       char *buf, size_t buflen)
 124 {
 125         int len, res;
 126
 127         if (sta == NULL) {
 128                 return snprintf(buf, buflen, "FAIL\n");
 129         }
 130
 131         len = 0;
 132         len += snprintf(buf + len, buflen - len, MACSTR "\n",
 133                         MAC2STR(sta->addr));
 134
 135         res = ieee802_11_get_mib_sta(hapd, sta, buf + len, buflen - len);
 136         if (res >= 0)
 137                 len += res;
 138         res = wpa_get_mib_sta(hapd, sta, buf + len, buflen - len);
 139         if (res >= 0)
 140                 len += res;
 141         res = ieee802_1x_get_mib_sta(hapd, sta, buf + len, buflen - len);
 142         if (res >= 0)
 143                 len += res;
 144
 145         return len;
 146 }
 147
 148
 149 static int hostapd_ctrl_iface_sta_first(struct hostapd_data *hapd,
 150                                         char *buf, size_t buflen)
 151 {
 152         return hostapd_ctrl_iface_sta_mib(hapd, hapd->sta_list, buf, buflen);
 153 }
 154
 155
 156 static int hostapd_ctrl_iface_sta(struct hostapd_data *hapd,
 157                                   const char *txtaddr,
 158                                   char *buf, size_t buflen)
 159 {
 160         u8 addr[ETH_ALEN];
 161
 162         if (hwaddr_aton(txtaddr, addr))
 163                 return snprintf(buf, buflen, "FAIL\n");
 164         return hostapd_ctrl_iface_sta_mib(hapd, ap_get_sta(hapd, addr),
 165                                           buf, buflen);
 166 }
 167
 168
 169 static int hostapd_ctrl_iface_sta_next(struct hostapd_data *hapd,
 170                                        const char *txtaddr,
 171                                        char *buf, size_t buflen)
 172 {
 173         u8 addr[ETH_ALEN];
 174         struct sta_info *sta;
 175
 176         if (hwaddr_aton(txtaddr, addr) ||
 177             (sta = ap_get_sta(hapd, addr)) == NULL)
 178                 return snprintf(buf, buflen, "FAIL\n");
 179         return hostapd_ctrl_iface_sta_mib(hapd, sta->next, buf, buflen);
 180 }
 181
 182
 183 static void hostapd_ctrl_iface_receive(int sock, void *eloop_ctx,
 184                                        void *sock_ctx)
 185 {
 186         struct hostapd_data *hapd = eloop_ctx;
 187         char buf[256];
 188         int res;
 189         struct sockaddr_un from;
 190         socklen_t fromlen = sizeof(from);
 191         char *reply;
 192         const int reply_size = 4096;
 193         int reply_len;
 194
 195         res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 196                        (struct sockaddr *) &from, &fromlen);
 197         if (res < 0) {
 198                 perror("recvfrom(ctrl_iface)");
 199                 return;
 200         }
 201         buf[res] = '\0';
 202         wpa_hexdump_ascii(MSG_DEBUG, "RX ctrl_iface", (u8 *) buf, res);
 203
 204         reply = malloc(reply_size);
 205         if (reply == NULL) {
 206                 sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
 207                        fromlen);
 208                 return;
 209         }
 210
 211         memcpy(reply, "OK\n", 3);
 212         reply_len = 3;
 213
 214         if (strcmp(buf, "PING") == 0) {
 215                 memcpy(reply, "PONG\n", 5);
 216                 reply_len = 5;
 217         } else if (strcmp(buf, "MIB") == 0) {
 218                 reply_len = ieee802_11_get_mib(hapd, reply, reply_size);
 219                 if (reply_len >= 0) {
 220                         res = wpa_get_mib(hapd, reply + reply_len,
 221                                           reply_size - reply_len);
 222                         if (res < 0)
 223                                 reply_len = -1;
 224                         else
 225                                 reply_len += res;
 226                 }
 227                 if (reply_len >= 0) {
 228                         res = ieee802_1x_get_mib(hapd, reply + reply_len,
 229                                                  reply_size - reply_len);
 230                         if (res < 0)
 231                                 reply_len = -1;
 232                         else
 233                                 reply_len += res;
 234                 }
 235                 if (reply_len >= 0) {
 236                         res = radius_client_get_mib(hapd->radius,
 237                                                     reply + reply_len,
 238                                                     reply_size - reply_len);
 239                         if (res < 0)
 240                                 reply_len = -1;
 241                         else
 242                                 reply_len += res;
 243                 }
 244         } else if (strcmp(buf, "STA-FIRST") == 0) {
 245                 reply_len = hostapd_ctrl_iface_sta_first(hapd, reply,
 246                                                          reply_size);
 247         } else if (strncmp(buf, "STA ", 4) == 0) {
 248                 reply_len = hostapd_ctrl_iface_sta(hapd, buf + 4, reply,
 249                                                    reply_size);
 250         } else if (strncmp(buf, "STA-NEXT ", 9) == 0) {
 251                 reply_len = hostapd_ctrl_iface_sta_next(hapd, buf + 9, reply,
 252                                                         reply_size);
 253         } else if (strcmp(buf, "ATTACH") == 0) {
 254                 if (hostapd_ctrl_iface_attach(hapd, &from, fromlen))
 255                         reply_len = -1;
 256         } else if (strcmp(buf, "DETACH") == 0) {
 257                 if (hostapd_ctrl_iface_detach(hapd, &from, fromlen))
 258                         reply_len = -1;
 259         } else if (strncmp(buf, "LEVEL ", 6) == 0) {
 260                 if (hostapd_ctrl_iface_level(hapd, &from, fromlen,
 261                                                     buf + 6))
 262                         reply_len = -1;
 263         } else {
 264                 memcpy(reply, "UNKNOWN COMMAND\n", 16);
 265                 reply_len = 16;
 266         }
 267
 268         if (reply_len < 0) {
 269                 memcpy(reply, "FAIL\n", 5);
 270                 reply_len = 5;
 271         }
 272         sendto(sock, reply, reply_len, 0, (struct sockaddr *) &from, fromlen);
 273         free(reply);
 274 }
 275
 276
 277 static char * hostapd_ctrl_iface_path(struct hostapd_data *hapd)
 278 {
 279         char *buf;
 280         size_t len;
 281
 282         if (hapd->conf->ctrl_interface == NULL)
 283                 return NULL;
 284
 285         len = strlen(hapd->conf->ctrl_interface) + strlen(hapd->conf->iface) +
 286                 2;
 287         buf = malloc(len);
 288         if (buf == NULL)
 289                 return NULL;
 290
 291         snprintf(buf, len, "%s/%s",
 292                  hapd->conf->ctrl_interface, hapd->conf->iface);
 293         return buf;
 294 }
 295
 296
 297 int hostapd_ctrl_iface_init(struct hostapd_data *hapd)
 298 {
 299         struct sockaddr_un addr;
 300         int s = -1;
 301         char *fname = NULL;
 302
 303         hapd->ctrl_sock = -1;
 304
 305         if (hapd->conf->ctrl_interface == NULL)
 306                 return 0;
 307
 308         if (mkdir(hapd->conf->ctrl_interface, S_IRWXU | S_IRWXG) < 0) {
 309                 if (errno == EEXIST) {
 310                         wpa_printf(MSG_DEBUG, "Using existing control "
 311                                    "interface directory.");
 312                 } else {
 313                         perror("mkdir[ctrl_interface]");
 314                         goto fail;
 315                 }
 316         }
 317
 318         if (chown(hapd->conf->ctrl_interface, 0,
 319                   hapd->conf->ctrl_interface_gid) < 0) {
 320                 perror("chown[ctrl_interface]");
 321                 return -1;
 322         }
 323
 324         if (strlen(hapd->conf->ctrl_interface) + 1 + strlen(hapd->conf->iface)
 325             >= sizeof(addr.sun_path))
 326                 goto fail;
 327
 328         s = socket(PF_UNIX, SOCK_DGRAM, 0);
 329         if (s < 0) {
 330                 perror("socket(PF_UNIX)");
 331                 goto fail;
 332         }
 333
 334         memset(&addr, 0, sizeof(addr));
 335         addr.sun_family = AF_UNIX;
 336         fname = hostapd_ctrl_iface_path(hapd);
 337         if (fname == NULL)
 338                 goto fail;
 339         strncpy(addr.sun_path, fname, sizeof(addr.sun_path));
 340         if (bind(s, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 341                 perror("bind(PF_UNIX)");
 342                 goto fail;
 343         }
 344
 345         if (chown(fname, 0, hapd->conf->ctrl_interface_gid) < 0) {
 346                 perror("chown[ctrl_interface/ifname]");
 347                 goto fail;
 348         }
 349
 350         if (chmod(fname, S_IRWXU | S_IRWXG) < 0) {
 351                 perror("chmod[ctrl_interface/ifname]");
 352                 goto fail;
 353         }
 354         free(fname);
 355
 356         hapd->ctrl_sock = s;
 357         eloop_register_read_sock(s, hostapd_ctrl_iface_receive, hapd,
 358                                  NULL);
 359
 360         return 0;
 361
 362 fail:
 363         if (s >= 0)
 364                 close(s);
 365         if (fname) {
 366                 unlink(fname);
 367                 free(fname);
 368         }
 369         return -1;
 370 }
 371
 372
 373 void hostapd_ctrl_iface_deinit(struct hostapd_data *hapd)
 374 {
 375         struct wpa_ctrl_dst *dst, *prev;
 376
 377         if (hapd->ctrl_sock > -1) {
 378                 char *fname;
 379                 eloop_unregister_read_sock(hapd->ctrl_sock);
 380                 close(hapd->ctrl_sock);
 381                 hapd->ctrl_sock = -1;
 382                 fname = hostapd_ctrl_iface_path(hapd);
 383                 if (fname)
 384                         unlink(fname);
 385                 free(fname);
 386
 387                 if (hapd->conf->ctrl_interface &&
 388                     rmdir(hapd->conf->ctrl_interface) < 0) {
 389                         if (errno == ENOTEMPTY) {
 390                                 wpa_printf(MSG_DEBUG, "Control interface "
 391                                            "directory not empty - leaving it "
 392                                            "behind");
 393                         } else {
 394                                 perror("rmdir[ctrl_interface]");
 395                         }
 396                 }
 397         }
 398
 399         dst = hapd->ctrl_dst;
 400         while (dst) {
 401                 prev = dst;
 402                 dst = dst->next;
 403                 free(prev);
 404         }
 405 }
 406
 407
 408 void hostapd_ctrl_iface_send(struct hostapd_data *hapd, int level,
 409                              char *buf, size_t len)
 410 {
 411         struct wpa_ctrl_dst *dst, *next;
 412         struct msghdr msg;
 413         int idx;
 414         struct iovec io[2];
 415         char levelstr[10];
 416
 417         dst = hapd->ctrl_dst;
 418         if (hapd->ctrl_sock < 0 || dst == NULL)
 419                 return;
 420
 421         snprintf(levelstr, sizeof(levelstr), "<%d>", level);
 422         io[0].iov_base = levelstr;
 423         io[0].iov_len = strlen(levelstr);
 424         io[1].iov_base = buf;
 425         io[1].iov_len = len;
 426         memset(&msg, 0, sizeof(msg));
 427         msg.msg_iov = io;
 428         msg.msg_iovlen = 2;
 429
 430         idx = 0;
 431         while (dst) {
 432                 next = dst->next;
 433                 if (level >= dst->debug_level) {
 434                         wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor send",
 435                                     (u8 *) dst->addr.sun_path, dst->addrlen);
 436                         msg.msg_name = &dst->addr;
 437                         msg.msg_namelen = dst->addrlen;
 438                         if (sendmsg(hapd->ctrl_sock, &msg, 0) < 0) {
 439                                 fprintf(stderr, "CTRL_IFACE monitor[%d]: ",
 440                                         idx);
 441                                 perror("sendmsg");
 442                                 dst->errors++;
 443                                 if (dst->errors > 10) {
 444                                         hostapd_ctrl_iface_detach(
 445                                                 hapd, &dst->addr,
 446                                                 dst->addrlen);
 447                                 }
 448                         } else
 449                                 dst->errors = 0;
 450                 }
 451                 idx++;
 452                 dst = next;
 453         }
 454 }