sys/netproto/802_11/ieee80211_proto.c

   1 /*
   2  * Copyright (c) 2001 Atsushi Onoe
   3  * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * Alternatively, this software may be distributed under the terms of the
  18  * GNU General Public License ("GPL") version 2 as published by the Free
  19  * Software Foundation.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/sys/net80211/ieee80211_proto.c,v 1.8 2004/04/02 20:22:25 sam Exp $
  33  * $DragonFly: src/sys/netproto/802_11/Attic/ieee80211_proto.c,v 1.1 2004/07/26 16:30:17 joerg Exp $
  34  */
  35
  36 /*
  37  * IEEE 802.11 protocol support.
  38  */
  39
  40 #include "opt_inet.h"
  41
  42 #include <sys/param.h>
  43 #include <sys/systm.h>
  44 #include <sys/mbuf.h>
  45 #include <sys/malloc.h>
  46 #include <sys/kernel.h>
  47 #include <sys/socket.h>
  48 #include <sys/sockio.h>
  49 #include <sys/endian.h>
  50 #include <sys/errno.h>
  51 #include <sys/bus.h>
  52 #include <sys/proc.h>
  53 #include <sys/sysctl.h>
  54
  55 #include <machine/atomic.h>
  56
  57 #include <net/if.h>
  58 #include <net/if_dl.h>
  59 #include <net/if_media.h>
  60 #include <net/if_arp.h>
  61 #include <net/ethernet.h>
  62 #include <net/if_llc.h>
  63
  64 #include <netproto/802_11/ieee80211_var.h>
  65
  66 #include <net/bpf.h>
  67
  68 #ifdef INET
  69 #include <netinet/in.h>
  70 #include <netinet/if_ether.h>
  71 #endif
  72
  73 #define IEEE80211_RATE2MBS(r)   (((r) & IEEE80211_RATE_VAL) / 2)
  74
  75 const char *ieee80211_mgt_subtype_name[] = {
  76         "assoc_req",    "assoc_resp",   "reassoc_req",  "reassoc_resp",
  77         "probe_req",    "probe_resp",   "reserved#6",   "reserved#7",
  78         "beacon",       "atim",         "disassoc",     "auth",
  79         "deauth",       "reserved#13",  "reserved#14",  "reserved#15"
  80 };
  81 const char *ieee80211_state_name[IEEE80211_S_MAX] = {
  82         "INIT",         /* IEEE80211_S_INIT */
  83         "SCAN",         /* IEEE80211_S_SCAN */
  84         "AUTH",         /* IEEE80211_S_AUTH */
  85         "ASSOC",        /* IEEE80211_S_ASSOC */
  86         "RUN"           /* IEEE80211_S_RUN */
  87 };
  88
  89 static int ieee80211_newstate(struct ieee80211com *, enum ieee80211_state, int);
  90
  91 void
  92 ieee80211_proto_attach(struct ifnet *ifp)
  93 {
  94         struct ieee80211com *ic = (void *)ifp;
  95
  96         ifp->if_hdrlen = sizeof(struct ieee80211_frame);
  97
  98 #ifdef notdef
  99         ic->ic_rtsthreshold = IEEE80211_RTS_DEFAULT;
 100 #else
 101         ic->ic_rtsthreshold = IEEE80211_RTS_MAX;
 102 #endif
 103         ic->ic_fragthreshold = 2346;            /* XXX not used yet */
 104         ic->ic_fixed_rate = -1;                 /* no fixed rate */
 105         ic->ic_protmode = IEEE80211_PROT_CTSONLY;
 106
 107         /* protocol state change handler */
 108         ic->ic_newstate = ieee80211_newstate;
 109
 110         /* initialize management frame handlers */
 111         ic->ic_recv_mgmt = ieee80211_recv_mgmt;
 112         ic->ic_send_mgmt = ieee80211_send_mgmt;
 113 }
 114
 115 void
 116 ieee80211_proto_detach(struct ifnet *ifp)
 117 {
 118         struct ieee80211com *ic = (void *)ifp;
 119
 120         IF_DRAIN(&ic->ic_mgtq);
 121 }
 122
 123 void
 124 ieee80211_print_essid(uint8_t *essid, int len)
 125 {
 126         int i;
 127         uint8_t *p;
 128
 129         if (len > IEEE80211_NWID_LEN)
 130                 len = IEEE80211_NWID_LEN;
 131         /* determine printable or not */
 132         for (i = 0, p = essid; i < len; i++, p++) {
 133                 if (*p < ' ' || *p > 0x7e)
 134                         break;
 135         }
 136         if (i == len) {
 137                 printf("\"");
 138                 for (i = 0, p = essid; i < len; i++, p++)
 139                         printf("%c", *p);
 140                 printf("\"");
 141         } else {
 142                 printf("0x");
 143                 for (i = 0, p = essid; i < len; i++, p++)
 144                         printf("%02x", *p);
 145         }
 146 }
 147
 148 void
 149 ieee80211_dump_pkt(uint8_t *buf, int len, int rate, int rssi)
 150 {
 151         struct ieee80211_frame *wh;
 152         int i;
 153
 154         wh = (struct ieee80211_frame *)buf;
 155         switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
 156         case IEEE80211_FC1_DIR_NODS:
 157                 printf("NODS %6D->%6D(%6D)", wh->i_addr2, ":",
 158                        wh->i_addr1, ":", wh->i_addr3, ":");
 159                 break;
 160         case IEEE80211_FC1_DIR_TODS:
 161                 printf("TODS %6D->%6D(%6D)", wh->i_addr2, ":",
 162                        wh->i_addr3, ":", wh->i_addr1, ":");
 163                 break;
 164         case IEEE80211_FC1_DIR_FROMDS:
 165                 printf("FRDS %6D->%6D(%6D)", wh->i_addr3, ":",
 166                        wh->i_addr1, ":", wh->i_addr2, ":");
 167                 break;
 168         case IEEE80211_FC1_DIR_DSTODS:
 169                 printf("DSDS %6D->%6D(%6D->%6D)", (uint8_t *)&wh[1], ":",
 170                        wh->i_addr3, ":", wh->i_addr2, ":", wh->i_addr1, ":");
 171                 break;
 172         }
 173         switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
 174         case IEEE80211_FC0_TYPE_DATA:
 175                 printf(" data");
 176                 break;
 177         case IEEE80211_FC0_TYPE_MGT:
 178                 printf(" %s", ieee80211_mgt_subtype_name[
 179                     (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK)
 180                     >> IEEE80211_FC0_SUBTYPE_SHIFT]);
 181                 break;
 182         default:
 183                 printf(" type#%d", wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK);
 184                 break;
 185         }
 186         if (wh->i_fc[1] & IEEE80211_FC1_WEP)
 187                 printf(" WEP");
 188         if (rate >= 0)
 189                 printf(" %dM", rate / 2);
 190         if (rssi >= 0)
 191                 printf(" +%d", rssi);
 192         printf("\n");
 193         if (len > 0) {
 194                 for (i = 0; i < len; i++) {
 195                         if ((i & 1) == 0)
 196                                 printf(" ");
 197                         printf("%02x", buf[i]);
 198                 }
 199                 printf("\n");
 200         }
 201 }
 202
 203 int
 204 ieee80211_fix_rate(struct ieee80211com *ic, struct ieee80211_node *ni, int flags)
 205 {
 206 #define RV(v)   ((v) & IEEE80211_RATE_VAL)
 207         int i, j, ignore, error;
 208         int okrate, badrate;
 209         struct ieee80211_rateset *srs, *nrs;
 210         uint8_t r;
 211
 212         error = 0;
 213         okrate = badrate = 0;
 214         srs = &ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
 215         nrs = &ni->ni_rates;
 216         for (i = 0; i < nrs->rs_nrates; ) {
 217                 ignore = 0;
 218                 if (flags & IEEE80211_F_DOSORT) {
 219                         /*
 220                          * Sort rates.
 221                          */
 222                         for (j = i + 1; j < nrs->rs_nrates; j++) {
 223                                 if (RV(nrs->rs_rates[i]) > RV(nrs->rs_rates[j])) {
 224                                         r = nrs->rs_rates[i];
 225                                         nrs->rs_rates[i] = nrs->rs_rates[j];
 226                                         nrs->rs_rates[j] = r;
 227                                 }
 228                         }
 229                 }
 230                 r = nrs->rs_rates[i] & IEEE80211_RATE_VAL;
 231                 badrate = r;
 232                 if (flags & IEEE80211_F_DOFRATE) {
 233                         /*
 234                          * Apply fixed rate constraint.  Note that we do
 235                          * not apply the constraint to basic rates as
 236                          * otherwise we may not be able to associate if
 237                          * the rate set we submit to the AP is invalid
 238                          * (e.g. fix rate at 36Mb/s which is not a basic
 239                          * rate for 11a operation).
 240                          */
 241                         if ((nrs->rs_rates[i] & IEEE80211_RATE_BASIC) == 0 &&
 242                             ic->ic_fixed_rate >= 0 &&
 243                             r != RV(srs->rs_rates[ic->ic_fixed_rate]))
 244                                 ignore++;
 245                 }
 246                 if (flags & IEEE80211_F_DONEGO) {
 247                         /*
 248                          * Check against supported rates.
 249                          */
 250                         for (j = 0; j < srs->rs_nrates; j++) {
 251                                 if (r == RV(srs->rs_rates[j])) {
 252                                         /*
 253                                          * Overwrite with the supported rate
 254                                          * value so any basic rate bit is set.
 255                                          * This insures that response we send
 256                                          * to stations have the necessary basic
 257                                          * rate bit set.
 258                                          */
 259                                         nrs->rs_rates[i] = srs->rs_rates[j];
 260                                         break;
 261                                 }
 262                         }
 263                         if (j == srs->rs_nrates) {
 264                                 /*
 265                                  * A rate in the node's rate set is not
 266                                  * supported.  If this is a basic rate and we
 267                                  * are operating as an AP then this is an error.
 268                                  * Otherwise we just discard/ignore the rate.
 269                                  * Note that this is important for 11b stations
 270                                  * when they want to associate with an 11g AP.
 271                                  */
 272                                 if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
 273                                     (nrs->rs_rates[i] & IEEE80211_RATE_BASIC))
 274                                         error++;
 275                                 ignore++;
 276                         }
 277                 }
 278                 if (flags & IEEE80211_F_DODEL) {
 279                         /*
 280                          * Delete unacceptable rates.
 281                          */
 282                         if (ignore) {
 283                                 nrs->rs_nrates--;
 284                                 for (j = i; j < nrs->rs_nrates; j++)
 285                                         nrs->rs_rates[j] = nrs->rs_rates[j + 1];
 286                                 nrs->rs_rates[j] = 0;
 287                                 continue;
 288                         }
 289                 }
 290                 if (!ignore)
 291                         okrate = nrs->rs_rates[i];
 292                 i++;
 293         }
 294         if (okrate == 0 || error != 0)
 295                 return badrate | IEEE80211_RATE_BASIC;
 296         else
 297                 return RV(okrate);
 298 #undef RV
 299 }
 300
 301 static int
 302 ieee80211_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int mgt)
 303 {
 304         struct ifnet *ifp = &ic->ic_if;
 305         struct ieee80211_node *ni;
 306         enum ieee80211_state ostate;
 307         struct lwkt_tokref ilock;
 308
 309         ostate = ic->ic_state;
 310         IEEE80211_DPRINTF(("%s: %s -> %s\n", __func__,
 311                 ieee80211_state_name[ostate], ieee80211_state_name[nstate]));
 312         ic->ic_state = nstate;                  /* state transition */
 313         ni = ic->ic_bss;                        /* NB: no reference held */
 314         switch (nstate) {
 315         case IEEE80211_S_INIT:
 316                 switch (ostate) {
 317                 case IEEE80211_S_INIT:
 318                         break;
 319                 case IEEE80211_S_RUN:
 320                         switch (ic->ic_opmode) {
 321                         case IEEE80211_M_STA:
 322                                 IEEE80211_SEND_MGMT(ic, ni,
 323                                     IEEE80211_FC0_SUBTYPE_DISASSOC,
 324                                     IEEE80211_REASON_ASSOC_LEAVE);
 325                                 break;
 326                         case IEEE80211_M_HOSTAP:
 327                                 lwkt_gettoken(&ilock, &ic->ic_nodetoken);
 328                                 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
 329                                         if (ni->ni_associd == 0)
 330                                                 continue;
 331                                         IEEE80211_SEND_MGMT(ic, ni,
 332                                             IEEE80211_FC0_SUBTYPE_DISASSOC,
 333                                             IEEE80211_REASON_ASSOC_LEAVE);
 334                                 }
 335                                 lwkt_reltoken(&ilock);
 336                                 break;
 337                         default:
 338                                 break;
 339                         }
 340                         /* FALLTHRU */
 341                 case IEEE80211_S_ASSOC:
 342                         switch (ic->ic_opmode) {
 343                         case IEEE80211_M_STA:
 344                                 IEEE80211_SEND_MGMT(ic, ni,
 345                                     IEEE80211_FC0_SUBTYPE_DEAUTH,
 346                                     IEEE80211_REASON_AUTH_LEAVE);
 347                                 break;
 348                         case IEEE80211_M_HOSTAP:
 349                                 lwkt_gettoken(&ilock, &ic->ic_nodetoken);
 350                                 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
 351                                         IEEE80211_SEND_MGMT(ic, ni,
 352                                             IEEE80211_FC0_SUBTYPE_DEAUTH,
 353                                             IEEE80211_REASON_AUTH_LEAVE);
 354                                 }
 355                                 lwkt_reltoken(&ilock);
 356                                 break;
 357                         default:
 358                                 break;
 359                         }
 360                         /* FALLTHRU */
 361                 case IEEE80211_S_AUTH:
 362                 case IEEE80211_S_SCAN:
 363                         ic->ic_mgt_timer = 0;
 364                         IF_DRAIN(&ic->ic_mgtq);
 365                         if (ic->ic_wep_ctx != NULL) {
 366                                 free(ic->ic_wep_ctx, M_DEVBUF);
 367                                 ic->ic_wep_ctx = NULL;
 368                         }
 369                         ieee80211_free_allnodes(ic);
 370                         break;
 371                 }
 372                 break;
 373         case IEEE80211_S_SCAN:
 374                 ic->ic_flags &= ~IEEE80211_F_SIBSS;
 375                 /* initialize bss for probe request */
 376                 IEEE80211_ADDR_COPY(ni->ni_macaddr, ifp->if_broadcastaddr);
 377                 IEEE80211_ADDR_COPY(ni->ni_bssid, ifp->if_broadcastaddr);
 378                 ni->ni_rates = ic->ic_sup_rates[
 379                         ieee80211_chan2mode(ic, ni->ni_chan)];
 380                 ni->ni_associd = 0;
 381                 ni->ni_rstamp = 0;
 382                 switch (ostate) {
 383                 case IEEE80211_S_INIT:
 384                         if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
 385                             ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
 386                                 /*
 387                                  * AP operation and we already have a channel;
 388                                  * bypass the scan and startup immediately.
 389                                  */
 390                                 ieee80211_create_ibss(ic, ic->ic_des_chan);
 391                         } else {
 392                                 ieee80211_begin_scan(ifp);
 393                         }
 394                         break;
 395                 case IEEE80211_S_SCAN:
 396                         /* scan next */
 397                         if (ic->ic_flags & IEEE80211_F_ASCAN) {
 398                                 IEEE80211_SEND_MGMT(ic, ni,
 399                                     IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
 400                         }
 401                         break;
 402                 case IEEE80211_S_RUN:
 403                         /* beacon miss */
 404                         if (ifp->if_flags & IFF_DEBUG) {
 405                                 /* XXX bssid clobbered above */
 406                                 if_printf(ifp, "no recent beacons from %6D;"
 407                                     " rescanning\n",
 408                                     ic->ic_bss->ni_bssid, ":");
 409                         }
 410                         ieee80211_free_allnodes(ic);
 411                         /* FALLTHRU */
 412                 case IEEE80211_S_AUTH:
 413                 case IEEE80211_S_ASSOC:
 414                         /* timeout restart scan */
 415                         ni = ieee80211_find_node(ic, ic->ic_bss->ni_macaddr);
 416                         if (ni != NULL) {
 417                                 ni->ni_fails++;
 418                                 ieee80211_unref_node(&ni);
 419                         }
 420                         ieee80211_begin_scan(ifp);
 421                         break;
 422                 }
 423                 break;
 424         case IEEE80211_S_AUTH:
 425                 switch (ostate) {
 426                 case IEEE80211_S_INIT:
 427                         IEEE80211_DPRINTF(("%s: invalid transition\n",
 428                                 __func__));
 429                         break;
 430                 case IEEE80211_S_SCAN:
 431                         IEEE80211_SEND_MGMT(ic, ni,
 432                             IEEE80211_FC0_SUBTYPE_AUTH, 1);
 433                         break;
 434                 case IEEE80211_S_AUTH:
 435                 case IEEE80211_S_ASSOC:
 436                         switch (mgt) {
 437                         case IEEE80211_FC0_SUBTYPE_AUTH:
 438                                 /* ??? */
 439                                 IEEE80211_SEND_MGMT(ic, ni,
 440                                     IEEE80211_FC0_SUBTYPE_AUTH, 2);
 441                                 break;
 442                         case IEEE80211_FC0_SUBTYPE_DEAUTH:
 443                                 /* ignore and retry scan on timeout */
 444                                 break;
 445                         }
 446                         break;
 447                 case IEEE80211_S_RUN:
 448                         switch (mgt) {
 449                         case IEEE80211_FC0_SUBTYPE_AUTH:
 450                                 IEEE80211_SEND_MGMT(ic, ni,
 451                                     IEEE80211_FC0_SUBTYPE_AUTH, 2);
 452                                 ic->ic_state = ostate;  /* stay RUN */
 453                                 break;
 454                         case IEEE80211_FC0_SUBTYPE_DEAUTH:
 455                                 /* try to reauth */
 456                                 IEEE80211_SEND_MGMT(ic, ni,
 457                                     IEEE80211_FC0_SUBTYPE_AUTH, 1);
 458                                 break;
 459                         }
 460                         break;
 461                 }
 462                 break;
 463         case IEEE80211_S_ASSOC:
 464                 switch (ostate) {
 465                 case IEEE80211_S_INIT:
 466                 case IEEE80211_S_SCAN:
 467                 case IEEE80211_S_ASSOC:
 468                         IEEE80211_DPRINTF(("%s: invalid transition\n",
 469                                 __func__));
 470                         break;
 471                 case IEEE80211_S_AUTH:
 472                         IEEE80211_SEND_MGMT(ic, ni,
 473                             IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 0);
 474                         break;
 475                 case IEEE80211_S_RUN:
 476                         IEEE80211_SEND_MGMT(ic, ni,
 477                             IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 1);
 478                         break;
 479                 }
 480                 break;
 481         case IEEE80211_S_RUN:
 482                 switch (ostate) {
 483                 case IEEE80211_S_INIT:
 484                 case IEEE80211_S_AUTH:
 485                 case IEEE80211_S_RUN:
 486                         IEEE80211_DPRINTF(("%s: invalid transition\n",
 487                                 __func__));
 488                         break;
 489                 case IEEE80211_S_SCAN:          /* adhoc/hostap mode */
 490                 case IEEE80211_S_ASSOC:         /* infra mode */
 491                         KASSERT(ni->ni_txrate < ni->ni_rates.rs_nrates,
 492                                 ("%s: bogus xmit rate %u setup\n", __func__,
 493                                         ni->ni_txrate));
 494                         if (ifp->if_flags & IFF_DEBUG) {
 495                                 if_printf(ifp, " ");
 496                                 if (ic->ic_opmode == IEEE80211_M_STA)
 497                                         printf("associated ");
 498                                 else
 499                                         printf("synchronized ");
 500                                 printf("with %6D ssid ", ni->ni_bssid, ":");
 501                                 ieee80211_print_essid(ic->ic_bss->ni_essid,
 502                                     ni->ni_esslen);
 503                                 printf(" channel %d start %uMb\n",
 504                                         ieee80211_chan2ieee(ic, ni->ni_chan),
 505                                         IEEE80211_RATE2MBS(ni->ni_rates.rs_rates[ni->ni_txrate]));
 506                         }
 507                         ic->ic_mgt_timer = 0;
 508                         (*ifp->if_start)(ifp);
 509                         break;
 510                 }
 511                 break;
 512         }
 513         return 0;
 514 }