net/ieee80211/softmac/ieee80211softmac_io.c

   1 /*
   2  * Some parts based on code from net80211
   3  * Copyright (c) 2001 Atsushi Onoe
   4  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * Alternatively, this software may be distributed under the terms of the
  19  * GNU General Public License ("GPL") version 2 as published by the Free
  20  * Software Foundation.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  */
  34
  35 #include "ieee80211softmac_priv.h"
  36
  37 /* Helper functions for inserting data into the frames */
  38
  39 /*
  40  * Adds an ESSID element to the frame
  41  *
  42  */
  43 static u8 *
  44 ieee80211softmac_add_essid(u8 *dst, struct ieee80211softmac_essid *essid)
  45 {
  46         if (essid) {
  47                 *dst++ = MFIE_TYPE_SSID;
  48                 *dst++ = essid->len;
  49                 memcpy(dst, essid->data, essid->len);
  50                 return dst+essid->len;
  51         } else {
  52                 *dst++ = MFIE_TYPE_SSID;
  53                 *dst++ = 0;
  54                 return dst;
  55         }
  56 }
  57
  58 /* Adds Supported Rates and if required Extended Rates Information Element
  59  * to the frame, ASSUMES WE HAVE A SORTED LIST OF RATES */
  60 static u8 *
  61 ieee80211softmac_frame_add_rates(u8 *dst, const struct ieee80211softmac_ratesinfo *r)
  62 {
  63         int cck_len, ofdm_len;
  64         *dst++ = MFIE_TYPE_RATES;
  65
  66         for(cck_len=0; ieee80211_is_cck_rate(r->rates[cck_len]) && (cck_len < r->count);cck_len++);
  67
  68         if(cck_len > IEEE80211SOFTMAC_MAX_RATES_LEN)
  69                 cck_len = IEEE80211SOFTMAC_MAX_RATES_LEN;
  70         *dst++ = cck_len;
  71         memcpy(dst, r->rates, cck_len);
  72         dst += cck_len;
  73
  74         if(cck_len < r->count){
  75                 for (ofdm_len=0; ieee80211_is_ofdm_rate(r->rates[ofdm_len + cck_len]) && (ofdm_len + cck_len < r->count); ofdm_len++);
  76                 if (ofdm_len > 0) {
  77                         if (ofdm_len > IEEE80211SOFTMAC_MAX_EX_RATES_LEN)
  78                                 ofdm_len = IEEE80211SOFTMAC_MAX_EX_RATES_LEN;
  79                         *dst++ = MFIE_TYPE_RATES_EX;
  80                         *dst++ = ofdm_len;
  81                         memcpy(dst, r->rates + cck_len, ofdm_len);
  82                         dst += ofdm_len;
  83                 }
  84         }
  85         return dst;
  86 }
  87
  88 /* Allocate a management frame */
  89 static u8 *
  90 ieee80211softmac_alloc_mgt(u32 size)
  91 {
  92         u8 * data;
  93
  94         /* Add the header and FCS to the size */
  95         size = size + IEEE80211_3ADDR_LEN;
  96         if(size > IEEE80211_DATA_LEN)
  97                 return NULL;
  98         /* Allocate the frame */
  99         data = kzalloc(size, GFP_ATOMIC);
 100         return data;
 101 }
 102
 103 /*
 104  * Add a 2 Address Header
 105  */
 106 static void
 107 ieee80211softmac_hdr_2addr(struct ieee80211softmac_device *mac,
 108         struct ieee80211_hdr_2addr *header, u32 type, u8 *dest)
 109 {
 110         /* Fill in the frame control flags */
 111         header->frame_ctl = cpu_to_le16(type);
 112         /* Control packets always have WEP turned off */
 113         if(type > IEEE80211_STYPE_CFENDACK && type < IEEE80211_STYPE_PSPOLL)
 114                 header->frame_ctl |= mac->ieee->sec.level ? cpu_to_le16(IEEE80211_FCTL_PROTECTED) : 0;
 115
 116         /* Fill in the duration */
 117         header->duration_id = 0;
 118         /* FIXME: How do I find this?
 119          * calculate. But most drivers just fill in 0 (except if it's a station id of course) */
 120
 121         /* Fill in the Destination Address */
 122         if(dest == NULL)
 123                 memset(header->addr1, 0xFF, ETH_ALEN);
 124         else
 125                 memcpy(header->addr1, dest, ETH_ALEN);
 126         /* Fill in the Source Address */
 127         memcpy(header->addr2, mac->ieee->dev->dev_addr, ETH_ALEN);
 128
 129 }
 130
 131
 132 /* Add a 3 Address Header */
 133 static void
 134 ieee80211softmac_hdr_3addr(struct ieee80211softmac_device *mac,
 135         struct ieee80211_hdr_3addr *header, u32 type, u8 *dest, u8 *bssid)
 136 {
 137         /* This is common with 2addr, so use that instead */
 138         ieee80211softmac_hdr_2addr(mac, (struct ieee80211_hdr_2addr *)header, type, dest);
 139
 140         /* Fill in the BSS ID */
 141         if(bssid == NULL)
 142                 memset(header->addr3, 0xFF, ETH_ALEN);
 143         else
 144                 memcpy(header->addr3, bssid, ETH_ALEN);
 145
 146         /* Fill in the sequence # */
 147         /* FIXME: I need to add this to the softmac struct
 148          * shouldn't the sequence number be in ieee80211? */
 149 }
 150
 151 static u16
 152 ieee80211softmac_capabilities(struct ieee80211softmac_device *mac,
 153         struct ieee80211softmac_network *net)
 154 {
 155         u16 capability = 0;
 156
 157         /* ESS and IBSS bits are set according to the current mode */
 158         switch (mac->ieee->iw_mode) {
 159         case IW_MODE_INFRA:
 160                 capability = cpu_to_le16(WLAN_CAPABILITY_ESS);
 161                 break;
 162         case IW_MODE_ADHOC:
 163                 capability = cpu_to_le16(WLAN_CAPABILITY_IBSS);
 164                 break;
 165         case IW_MODE_AUTO:
 166                 capability = net->capabilities &
 167                         (WLAN_CAPABILITY_ESS|WLAN_CAPABILITY_IBSS);
 168                 break;
 169         default:
 170                 /* bleh. we don't ever go to these modes */
 171                 printk(KERN_ERR PFX "invalid iw_mode!\n");
 172                 break;
 173         }
 174
 175         /* CF Pollable / CF Poll Request */
 176         /* Needs to be implemented, for now, the 0's == not supported */
 177
 178         /* Privacy Bit */
 179         capability |= mac->ieee->sec.level ?
 180                 cpu_to_le16(WLAN_CAPABILITY_PRIVACY) : 0;
 181
 182         /* Short Preamble */
 183         /* Always supported: we probably won't ever be powering devices which
 184          * dont support this... */
 185         capability |= WLAN_CAPABILITY_SHORT_PREAMBLE;
 186
 187         /* PBCC */
 188         /* Not widely used */
 189
 190         /* Channel Agility */
 191         /* Not widely used */
 192
 193         /* Short Slot */
 194         /* Will be implemented later */
 195
 196         /* DSSS-OFDM */
 197         /* Not widely used */
 198
 199         return capability;
 200 }
 201
 202 /*****************************************************************************
 203  * Create Management packets
 204  *****************************************************************************/
 205
 206 /* Creates an association request packet */
 207 static u32
 208 ieee80211softmac_assoc_req(struct ieee80211_assoc_request **pkt,
 209         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 210 {
 211         u8 *data;
 212         (*pkt) = (struct ieee80211_assoc_request *)ieee80211softmac_alloc_mgt(
 213                 2 +             /* Capability Info */
 214                 2 +             /* Listen Interval */
 215                 /* SSID IE */
 216                 1 + 1 + IW_ESSID_MAX_SIZE +
 217                 /* Rates IE */
 218                 1 + 1 + IEEE80211SOFTMAC_MAX_RATES_LEN +
 219                 /* Extended Rates IE */
 220                 1 + 1 + IEEE80211SOFTMAC_MAX_EX_RATES_LEN +
 221                 /* WPA IE if present */
 222                 mac->wpa.IElen
 223                 /* Other IE's?  Optional?
 224                  * Yeah, probably need an extra IE parameter -- lots of vendors like to
 225                  * fill in their own IEs */
 226         );
 227         if (unlikely((*pkt) == NULL))
 228                 return 0;
 229         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_ASSOC_REQ, net->bssid, net->bssid);
 230
 231         /* Fill in the capabilities */
 232         (*pkt)->capability = ieee80211softmac_capabilities(mac, net);
 233
 234         /* Fill in Listen Interval (?) */
 235         (*pkt)->listen_interval = cpu_to_le16(10);
 236
 237         data = (u8 *)(*pkt)->info_element;
 238         /* Add SSID */
 239         data = ieee80211softmac_add_essid(data, &net->essid);
 240         /* Add Rates */
 241         data = ieee80211softmac_frame_add_rates(data, &mac->ratesinfo);
 242         /* Add WPA IE */
 243         if (mac->wpa.IElen && mac->wpa.IE) {
 244                 memcpy(data, mac->wpa.IE, mac->wpa.IElen);
 245                 data += mac->wpa.IElen;
 246         }
 247         /* Return the number of used bytes */
 248         return (data - (u8*)(*pkt));
 249 }
 250
 251 /* Create a reassociation request packet */
 252 static u32
 253 ieee80211softmac_reassoc_req(struct ieee80211_reassoc_request **pkt,
 254         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 255 {
 256         u8 *data;
 257         (*pkt) = (struct ieee80211_reassoc_request *)ieee80211softmac_alloc_mgt(
 258                 2 +             /* Capability Info */
 259                 2 +             /* Listen Interval */
 260                 ETH_ALEN +      /* AP MAC */
 261                 /* SSID IE */
 262                 1 + 1 + IW_ESSID_MAX_SIZE +
 263                 /* Rates IE */
 264                 1 + 1 + IEEE80211SOFTMAC_MAX_RATES_LEN +
 265                 /* Extended Rates IE */
 266                 1 + 1 + IEEE80211SOFTMAC_MAX_EX_RATES_LEN
 267                 /* Other IE's? */
 268         );
 269         if (unlikely((*pkt) == NULL))
 270                 return 0;
 271         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_REASSOC_REQ, net->bssid, net->bssid);
 272
 273         /* Fill in the capabilities */
 274         (*pkt)->capability = ieee80211softmac_capabilities(mac, net);
 275
 276         /* Fill in Listen Interval (?) */
 277         (*pkt)->listen_interval = cpu_to_le16(10);
 278         /* Fill in the current AP MAC */
 279         memcpy((*pkt)->current_ap, mac->ieee->bssid, ETH_ALEN);
 280
 281         data = (u8 *)(*pkt)->info_element;
 282         /* Add SSID */
 283         data = ieee80211softmac_add_essid(data, &net->essid);
 284         /* Add Rates */
 285         data = ieee80211softmac_frame_add_rates(data, &mac->ratesinfo);
 286         /* Return packet size */
 287         return (data - (u8 *)(*pkt));
 288 }
 289
 290 /* Create an authentication packet */
 291 static u32
 292 ieee80211softmac_auth(struct ieee80211_auth **pkt,
 293         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net,
 294         u16 transaction, u16 status, int *encrypt_mpdu)
 295 {
 296         u8 *data;
 297         int auth_mode = mac->ieee->sec.auth_mode;
 298         int is_shared_response = (auth_mode == WLAN_AUTH_SHARED_KEY
 299                 && transaction == IEEE80211SOFTMAC_AUTH_SHARED_RESPONSE);
 300
 301         /* Allocate Packet */
 302         (*pkt) = (struct ieee80211_auth *)ieee80211softmac_alloc_mgt(
 303                 2 +             /* Auth Algorithm */
 304                 2 +             /* Auth Transaction Seq */
 305                 2 +             /* Status Code */
 306                  /* Challenge Text IE */
 307                 (is_shared_response ? 1 + 1 + net->challenge_len : 0)
 308         );
 309         if (unlikely((*pkt) == NULL))
 310                 return 0;
 311         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_AUTH, net->bssid, net->bssid);
 312
 313         /* Algorithm */
 314         (*pkt)->algorithm = cpu_to_le16(auth_mode);
 315         /* Transaction */
 316         (*pkt)->transaction = cpu_to_le16(transaction);
 317         /* Status */
 318         (*pkt)->status = cpu_to_le16(status);
 319
 320         data = (u8 *)(*pkt)->info_element;
 321         /* Challenge Text */
 322         if (is_shared_response) {
 323                 *data = MFIE_TYPE_CHALLENGE;
 324                 data++;
 325
 326                 /* Copy the challenge in */
 327                 *data = net->challenge_len;
 328                 data++;
 329                 memcpy(data, net->challenge, net->challenge_len);
 330                 data += net->challenge_len;
 331
 332                 /* Make sure this frame gets encrypted with the shared key */
 333                 *encrypt_mpdu = 1;
 334         } else
 335                 *encrypt_mpdu = 0;
 336
 337         /* Return the packet size */
 338         return (data - (u8 *)(*pkt));
 339 }
 340
 341 /* Create a disassocation or deauthentication packet */
 342 static u32
 343 ieee80211softmac_disassoc_deauth(struct ieee80211_disassoc **pkt,
 344         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net,
 345         u16 type, u16 reason)
 346 {
 347         /* Allocate Packet */
 348         (*pkt) = (struct ieee80211_disassoc *)ieee80211softmac_alloc_mgt(2);
 349         if (unlikely((*pkt) == NULL))
 350                 return 0;
 351         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), type, net->bssid, net->bssid);
 352         /* Reason */
 353         (*pkt)->reason = cpu_to_le16(reason);
 354         /* Return the packet size */
 355         return (2 + IEEE80211_3ADDR_LEN);
 356 }
 357
 358 /* Create a probe request packet */
 359 static u32
 360 ieee80211softmac_probe_req(struct ieee80211_probe_request **pkt,
 361         struct ieee80211softmac_device *mac, struct ieee80211softmac_essid *essid)
 362 {
 363         u8 *data;
 364         /* Allocate Packet */
 365         (*pkt) = (struct ieee80211_probe_request *)ieee80211softmac_alloc_mgt(
 366                 /* SSID of requested network */
 367                 1 + 1 + IW_ESSID_MAX_SIZE +
 368                 /* Rates IE */
 369                 1 + 1 + IEEE80211SOFTMAC_MAX_RATES_LEN +
 370                 /* Extended Rates IE */
 371                 1 + 1 + IEEE80211SOFTMAC_MAX_EX_RATES_LEN
 372         );
 373         if (unlikely((*pkt) == NULL))
 374                 return 0;
 375         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_PROBE_REQ, NULL, NULL);
 376
 377         data = (u8 *)(*pkt)->info_element;
 378         /* Add ESSID (can be NULL) */
 379         data = ieee80211softmac_add_essid(data, essid);
 380         /* Add Rates */
 381         data = ieee80211softmac_frame_add_rates(data, &mac->ratesinfo);
 382         /* Return packet size */
 383         return (data - (u8 *)(*pkt));
 384 }
 385
 386 /* Create a probe response packet */
 387 /* FIXME: Not complete */
 388 static u32
 389 ieee80211softmac_probe_resp(struct ieee80211_probe_response **pkt,
 390         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 391 {
 392         u8 *data;
 393         /* Allocate Packet */
 394         (*pkt) = (struct ieee80211_probe_response *)ieee80211softmac_alloc_mgt(
 395                 8 +             /* Timestamp */
 396                 2 +             /* Beacon Interval */
 397                 2 +             /* Capability Info */
 398                                 /* SSID IE */
 399                 1 + 1 + IW_ESSID_MAX_SIZE +
 400                 7 +             /* FH Parameter Set */
 401                 2 +             /* DS Parameter Set */
 402                 8 +             /* CF Parameter Set */
 403                 4               /* IBSS Parameter Set */
 404         );
 405         if (unlikely((*pkt) == NULL))
 406                 return 0;
 407         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_PROBE_RESP, net->bssid, net->bssid);
 408         data = (u8 *)(*pkt)->info_element;
 409
 410         /* Return the packet size */
 411         return (data - (u8 *)(*pkt));
 412 }
 413
 414
 415 /* Sends a manangement packet
 416  * FIXME: document the use of the arg parameter
 417  * for _AUTH: (transaction #) | (status << 16)
 418  */
 419 int
 420 ieee80211softmac_send_mgt_frame(struct ieee80211softmac_device *mac,
 421         void *ptrarg, u32 type, u32 arg)
 422 {
 423         void *pkt = NULL;
 424         u32 pkt_size = 0;
 425         int encrypt_mpdu = 0;
 426
 427         switch(type) {
 428         case IEEE80211_STYPE_ASSOC_REQ:
 429                 pkt_size = ieee80211softmac_assoc_req((struct ieee80211_assoc_request **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg);
 430                 break;
 431         case IEEE80211_STYPE_REASSOC_REQ:
 432                 pkt_size = ieee80211softmac_reassoc_req((struct ieee80211_reassoc_request **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg);
 433                 break;
 434         case IEEE80211_STYPE_AUTH:
 435                 pkt_size = ieee80211softmac_auth((struct ieee80211_auth **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg, (u16)(arg & 0xFFFF), (u16) (arg >> 16), &encrypt_mpdu);
 436                 break;
 437         case IEEE80211_STYPE_DISASSOC:
 438         case IEEE80211_STYPE_DEAUTH:
 439                 pkt_size = ieee80211softmac_disassoc_deauth((struct ieee80211_disassoc **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg, type, (u16)(arg & 0xFFFF));
 440                 break;
 441         case IEEE80211_STYPE_PROBE_REQ:
 442                 pkt_size = ieee80211softmac_probe_req((struct ieee80211_probe_request **)(&pkt), mac, (struct ieee80211softmac_essid *)ptrarg);
 443                 break;
 444         case IEEE80211_STYPE_PROBE_RESP:
 445                 pkt_size = ieee80211softmac_probe_resp((struct ieee80211_probe_response **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg);
 446                 break;
 447         default:
 448                 printkl(KERN_DEBUG PFX "Unsupported Management Frame type: %i\n", type);
 449                 return -EINVAL;
 450         };
 451
 452         if(pkt_size == 0 || pkt == NULL) {
 453                 printkl(KERN_DEBUG PFX "Error, packet is nonexistant or 0 length\n");
 454                 return -ENOMEM;
 455         }
 456
 457         /* Send the packet to the ieee80211 layer for tx */
 458         /* we defined softmac->mgmt_xmit for this. Should we keep it
 459          * as it is (that means we'd need to wrap this into a txb),
 460          * modify the prototype (so it matches this function),
 461          * or get rid of it alltogether?
 462          * Does this work for you now?
 463          */
 464         ieee80211_tx_frame(mac->ieee, (struct ieee80211_hdr *)pkt,
 465                 IEEE80211_3ADDR_LEN, pkt_size, encrypt_mpdu);
 466
 467         kfree(pkt);
 468         return 0;
 469 }
 470
 471 /* Beacon handling */
 472 int ieee80211softmac_handle_beacon(struct net_device *dev,
 473         struct ieee80211_beacon *beacon,
 474         struct ieee80211_network *network)
 475 {
 476         struct ieee80211softmac_device *mac = ieee80211_priv(dev);
 477
 478         /* This might race, but we don't really care and it's not worth
 479          * adding heavyweight locking in this fastpath.
 480          */
 481         if (mac->associnfo.associated) {
 482                 if (memcmp(network->bssid, mac->associnfo.bssid, ETH_ALEN) == 0)
 483                         ieee80211softmac_process_erp(mac, network->erp_value);
 484         }
 485
 486         return 0;
 487 }
 488