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 = kmalloc(size, GFP_ATOMIC);
 100         memset(data, 0, size);
 101         return data;
 102 }
 103
 104 /*
 105  * Add a 2 Address Header
 106  */
 107 static void
 108 ieee80211softmac_hdr_2addr(struct ieee80211softmac_device *mac,
 109         struct ieee80211_hdr_2addr *header, u32 type, u8 *dest)
 110 {
 111         /* Fill in the frame control flags */
 112         header->frame_ctl = cpu_to_le16(type);
 113         /* Control packets always have WEP turned off */
 114         if(type > IEEE80211_STYPE_CFENDACK && type < IEEE80211_STYPE_PSPOLL)
 115                 header->frame_ctl |= mac->ieee->sec.level ? cpu_to_le16(IEEE80211_FCTL_PROTECTED) : 0;
 116
 117         /* Fill in the duration */
 118         header->duration_id = 0;
 119         /* FIXME: How do I find this?
 120          * calculate. But most drivers just fill in 0 (except if it's a station id of course) */
 121
 122         /* Fill in the Destination Address */
 123         if(dest == NULL)
 124                 memset(header->addr1, 0xFF, ETH_ALEN);
 125         else
 126                 memcpy(header->addr1, dest, ETH_ALEN);
 127         /* Fill in the Source Address */
 128         memcpy(header->addr2, mac->ieee->dev->dev_addr, ETH_ALEN);
 129
 130 }
 131
 132
 133 /* Add a 3 Address Header */
 134 static void
 135 ieee80211softmac_hdr_3addr(struct ieee80211softmac_device *mac,
 136         struct ieee80211_hdr_3addr *header, u32 type, u8 *dest, u8 *bssid)
 137 {
 138         /* This is common with 2addr, so use that instead */
 139         ieee80211softmac_hdr_2addr(mac, (struct ieee80211_hdr_2addr *)header, type, dest);
 140
 141         /* Fill in the BSS ID */
 142         if(bssid == NULL)
 143                 memset(header->addr3, 0xFF, ETH_ALEN);
 144         else
 145                 memcpy(header->addr3, bssid, ETH_ALEN);
 146
 147         /* Fill in the sequence # */
 148         /* FIXME: I need to add this to the softmac struct
 149          * shouldn't the sequence number be in ieee80211? */
 150 }
 151
 152
 153 /*****************************************************************************
 154  * Create Management packets
 155  *****************************************************************************/
 156
 157 /* Creates an association request packet */
 158 static u32
 159 ieee80211softmac_assoc_req(struct ieee80211_assoc_request **pkt,
 160         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 161 {
 162         u8 *data;
 163         (*pkt) = (struct ieee80211_assoc_request *)ieee80211softmac_alloc_mgt(
 164                 2 +             /* Capability Info */
 165                 2 +             /* Listen Interval */
 166                 /* SSID IE */
 167                 1 + 1 + IW_ESSID_MAX_SIZE +
 168                 /* Rates IE */
 169                 1 + 1 + IEEE80211SOFTMAC_MAX_RATES_LEN +
 170                 /* Extended Rates IE */
 171                 1 + 1 + IEEE80211SOFTMAC_MAX_EX_RATES_LEN +
 172                 /* WPA IE if present */
 173                 mac->wpa.IElen
 174                 /* Other IE's?  Optional?
 175                  * Yeah, probably need an extra IE parameter -- lots of vendors like to
 176                  * fill in their own IEs */
 177         );
 178         if (unlikely((*pkt) == NULL))
 179                 return 0;
 180         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_ASSOC_REQ, net->bssid, net->bssid);
 181
 182         /* Fill in capability Info */
 183         (*pkt)->capability = (mac->ieee->iw_mode == IW_MODE_MASTER) || (mac->ieee->iw_mode == IW_MODE_INFRA) ?
 184                 cpu_to_le16(WLAN_CAPABILITY_ESS) :
 185                 cpu_to_le16(WLAN_CAPABILITY_IBSS);
 186         /* Need to add this
 187         (*pkt)->capability |= mac->ieee->short_slot ?
 188                         cpu_to_le16(WLAN_CAPABILITY_SHORT_SLOT_TIME) : 0;
 189          */
 190         (*pkt)->capability |= mac->ieee->sec.level ? cpu_to_le16(WLAN_CAPABILITY_PRIVACY) : 0;
 191         /* Fill in Listen Interval (?) */
 192         (*pkt)->listen_interval = cpu_to_le16(10);
 193
 194         data = (u8 *)(*pkt)->info_element;
 195         /* Add SSID */
 196         data = ieee80211softmac_add_essid(data, &net->essid);
 197         /* Add Rates */
 198         data = ieee80211softmac_frame_add_rates(data, &mac->ratesinfo);
 199         /* Add WPA IE */
 200         if (mac->wpa.IElen && mac->wpa.IE) {
 201                 memcpy(data, mac->wpa.IE, mac->wpa.IElen);
 202                 data += mac->wpa.IElen;
 203         }
 204         /* Return the number of used bytes */
 205         return (data - (u8*)(*pkt));
 206 }
 207
 208 /* Create a reassociation request packet */
 209 static u32
 210 ieee80211softmac_reassoc_req(struct ieee80211_reassoc_request **pkt,
 211         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 212 {
 213         u8 *data;
 214         (*pkt) = (struct ieee80211_reassoc_request *)ieee80211softmac_alloc_mgt(
 215                 2 +             /* Capability Info */
 216                 2 +             /* Listen Interval */
 217                 ETH_ALEN +      /* AP MAC */
 218                 /* SSID IE */
 219                 1 + 1 + IW_ESSID_MAX_SIZE +
 220                 /* Rates IE */
 221                 1 + 1 + IEEE80211SOFTMAC_MAX_RATES_LEN +
 222                 /* Extended Rates IE */
 223                 1 + 1 + IEEE80211SOFTMAC_MAX_EX_RATES_LEN
 224                 /* Other IE's? */
 225         );
 226         if (unlikely((*pkt) == NULL))
 227                 return 0;
 228         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_REASSOC_REQ, net->bssid, net->bssid);
 229
 230         /* Fill in capability Info */
 231         (*pkt)->capability = mac->ieee->iw_mode == IW_MODE_MASTER ?
 232                                 cpu_to_le16(WLAN_CAPABILITY_ESS) :
 233                                 cpu_to_le16(WLAN_CAPABILITY_IBSS);
 234         /*
 235         (*pkt)->capability |= mac->ieee->short_slot ?
 236                         cpu_to_le16(WLAN_CAPABILITY_SHORT_SLOT_TIME) : 0;
 237          */
 238         (*pkt)->capability |= mac->ieee->sec.level ?
 239                         cpu_to_le16(WLAN_CAPABILITY_PRIVACY) : 0;
 240
 241         /* Fill in Listen Interval (?) */
 242         (*pkt)->listen_interval = cpu_to_le16(10);
 243         /* Fill in the current AP MAC */
 244         memcpy((*pkt)->current_ap, mac->ieee->bssid, ETH_ALEN);
 245
 246         data = (u8 *)(*pkt)->info_element;
 247         /* Add SSID */
 248         data = ieee80211softmac_add_essid(data, &net->essid);
 249         /* Add Rates */
 250         data = ieee80211softmac_frame_add_rates(data, &mac->ratesinfo);
 251         /* Return packet size */
 252         return (data - (u8 *)(*pkt));
 253 }
 254
 255 /* Create an authentication packet */
 256 static u32
 257 ieee80211softmac_auth(struct ieee80211_auth **pkt,
 258         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net,
 259         u16 transaction, u16 status)
 260 {
 261         u8 *data;
 262         /* Allocate Packet */
 263         (*pkt) = (struct ieee80211_auth *)ieee80211softmac_alloc_mgt(
 264                 2 +             /* Auth Algorithm */
 265                 2 +             /* Auth Transaction Seq */
 266                 2 +             /* Status Code */
 267                  /* Challenge Text IE */
 268                 mac->ieee->open_wep ? 0 :
 269                 1 + 1 + WLAN_AUTH_CHALLENGE_LEN
 270         );
 271         if (unlikely((*pkt) == NULL))
 272                 return 0;
 273         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_AUTH, net->bssid, net->bssid);
 274
 275         /* Algorithm */
 276         (*pkt)->algorithm = mac->ieee->open_wep ?
 277                 cpu_to_le16(WLAN_AUTH_OPEN) :
 278                 cpu_to_le16(WLAN_AUTH_SHARED_KEY);
 279         /* Transaction */
 280         (*pkt)->transaction = cpu_to_le16(transaction);
 281         /* Status */
 282         (*pkt)->status = cpu_to_le16(status);
 283
 284         data = (u8 *)(*pkt)->info_element;
 285         /* Challenge Text */
 286         if(!mac->ieee->open_wep){
 287                 *data = MFIE_TYPE_CHALLENGE;
 288                 data++;
 289
 290                 /* Copy the challenge in */
 291                 // *data = challenge length
 292                 // data += sizeof(u16);
 293                 // memcpy(data, challenge, challenge length);
 294                 // data += challenge length;
 295
 296                 /* Add the full size to the packet length */
 297         }
 298
 299         /* Return the packet size */
 300         return (data - (u8 *)(*pkt));
 301 }
 302
 303 /* Create a disassocation or deauthentication packet */
 304 static u32
 305 ieee80211softmac_disassoc_deauth(struct ieee80211_disassoc **pkt,
 306         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net,
 307         u16 type, u16 reason)
 308 {
 309         /* Allocate Packet */
 310         (*pkt) = (struct ieee80211_disassoc *)ieee80211softmac_alloc_mgt(2);
 311         if (unlikely((*pkt) == NULL))
 312                 return 0;
 313         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), type, net->bssid, net->bssid);
 314         /* Reason */
 315         (*pkt)->reason = cpu_to_le16(reason);
 316         /* Return the packet size */
 317         return (2 + IEEE80211_3ADDR_LEN);
 318 }
 319
 320 /* Create a probe request packet */
 321 static u32
 322 ieee80211softmac_probe_req(struct ieee80211_probe_request **pkt,
 323         struct ieee80211softmac_device *mac, struct ieee80211softmac_essid *essid)
 324 {
 325         u8 *data;
 326         /* Allocate Packet */
 327         (*pkt) = (struct ieee80211_probe_request *)ieee80211softmac_alloc_mgt(
 328                 /* SSID of requested network */
 329                 1 + 1 + IW_ESSID_MAX_SIZE +
 330                 /* Rates IE */
 331                 1 + 1 + IEEE80211SOFTMAC_MAX_RATES_LEN +
 332                 /* Extended Rates IE */
 333                 1 + 1 + IEEE80211SOFTMAC_MAX_EX_RATES_LEN
 334         );
 335         if (unlikely((*pkt) == NULL))
 336                 return 0;
 337         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_PROBE_REQ, NULL, NULL);
 338
 339         data = (u8 *)(*pkt)->info_element;
 340         /* Add ESSID (can be NULL) */
 341         data = ieee80211softmac_add_essid(data, essid);
 342         /* Add Rates */
 343         data = ieee80211softmac_frame_add_rates(data, &mac->ratesinfo);
 344         /* Return packet size */
 345         return (data - (u8 *)(*pkt));
 346 }
 347
 348 /* Create a probe response packet */
 349 /* FIXME: Not complete */
 350 static u32
 351 ieee80211softmac_probe_resp(struct ieee80211_probe_response **pkt,
 352         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net)
 353 {
 354         u8 *data;
 355         /* Allocate Packet */
 356         (*pkt) = (struct ieee80211_probe_response *)ieee80211softmac_alloc_mgt(
 357                 8 +             /* Timestamp */
 358                 2 +             /* Beacon Interval */
 359                 2 +             /* Capability Info */
 360                                 /* SSID IE */
 361                 1 + 1 + IW_ESSID_MAX_SIZE +
 362                 7 +             /* FH Parameter Set */
 363                 2 +             /* DS Parameter Set */
 364                 8 +             /* CF Parameter Set */
 365                 4               /* IBSS Parameter Set */
 366         );
 367         if (unlikely((*pkt) == NULL))
 368                 return 0;
 369         ieee80211softmac_hdr_3addr(mac, &((*pkt)->header), IEEE80211_STYPE_PROBE_RESP, net->bssid, net->bssid);
 370         data = (u8 *)(*pkt)->info_element;
 371
 372         /* Return the packet size */
 373         return (data - (u8 *)(*pkt));
 374 }
 375
 376
 377 /* Sends a manangement packet
 378  * FIXME: document the use of the arg parameter
 379  * for _AUTH: (transaction #) | (status << 16)
 380  */
 381 int
 382 ieee80211softmac_send_mgt_frame(struct ieee80211softmac_device *mac,
 383         void *ptrarg, u32 type, u32 arg)
 384 {
 385         void *pkt = NULL;
 386         u32 pkt_size = 0;
 387
 388         switch(type) {
 389         case IEEE80211_STYPE_ASSOC_REQ:
 390                 pkt_size = ieee80211softmac_assoc_req((struct ieee80211_assoc_request **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg);
 391                 break;
 392         case IEEE80211_STYPE_REASSOC_REQ:
 393                 pkt_size = ieee80211softmac_reassoc_req((struct ieee80211_reassoc_request **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg);
 394                 break;
 395         case IEEE80211_STYPE_AUTH:
 396                 pkt_size = ieee80211softmac_auth((struct ieee80211_auth **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg, (u16)(arg & 0xFFFF), (u16) (arg >> 16));
 397                 break;
 398         case IEEE80211_STYPE_DISASSOC:
 399         case IEEE80211_STYPE_DEAUTH:
 400                 pkt_size = ieee80211softmac_disassoc_deauth((struct ieee80211_disassoc **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg, type, (u16)(arg & 0xFFFF));
 401                 break;
 402         case IEEE80211_STYPE_PROBE_REQ:
 403                 pkt_size = ieee80211softmac_probe_req((struct ieee80211_probe_request **)(&pkt), mac, (struct ieee80211softmac_essid *)ptrarg);
 404                 break;
 405         case IEEE80211_STYPE_PROBE_RESP:
 406                 pkt_size = ieee80211softmac_probe_resp((struct ieee80211_probe_response **)(&pkt), mac, (struct ieee80211softmac_network *)ptrarg);
 407                 break;
 408         default:
 409                 printkl(KERN_DEBUG PFX "Unsupported Management Frame type: %i\n", type);
 410                 return -EINVAL;
 411         };
 412
 413         if(pkt_size == 0 || pkt == NULL) {
 414                 printkl(KERN_DEBUG PFX "Error, packet is nonexistant or 0 length\n");
 415                 return -ENOMEM;
 416         }
 417
 418         /* Send the packet to the ieee80211 layer for tx */
 419         /* we defined softmac->mgmt_xmit for this. Should we keep it
 420          * as it is (that means we'd need to wrap this into a txb),
 421          * modify the prototype (so it matches this function),
 422          * or get rid of it alltogether?
 423          * Does this work for you now?
 424          */
 425         ieee80211_tx_frame(mac->ieee, (struct ieee80211_hdr *)pkt, pkt_size);
 426
 427         kfree(pkt);
 428         return 0;
 429 }
 430
 431
 432 /* Create an rts/cts frame */
 433 static u32
 434 ieee80211softmac_rts_cts(struct ieee80211_hdr_2addr **pkt,
 435         struct ieee80211softmac_device *mac, struct ieee80211softmac_network *net,
 436         u32 type)
 437 {
 438         /* Allocate Packet */
 439         (*pkt) = kmalloc(IEEE80211_2ADDR_LEN, GFP_ATOMIC);
 440         memset(*pkt, 0, IEEE80211_2ADDR_LEN);
 441         if((*pkt) == NULL)
 442                 return 0;
 443         ieee80211softmac_hdr_2addr(mac, (*pkt), type, net->bssid);
 444         return IEEE80211_2ADDR_LEN;
 445 }
 446
 447
 448 /* Sends a control packet */
 449 static int
 450 ieee80211softmac_send_ctl_frame(struct ieee80211softmac_device *mac,
 451         struct ieee80211softmac_network *net, u32 type, u32 arg)
 452 {
 453         void *pkt = NULL;
 454         u32 pkt_size = 0;
 455
 456         switch(type) {
 457         case IEEE80211_STYPE_RTS:
 458         case IEEE80211_STYPE_CTS:
 459                 pkt_size = ieee80211softmac_rts_cts((struct ieee80211_hdr_2addr **)(&pkt), mac, net, type);
 460                 break;
 461         default:
 462                 printkl(KERN_DEBUG PFX "Unsupported Control Frame type: %i\n", type);
 463                 return -EINVAL;
 464         }
 465
 466         if(pkt_size == 0)
 467                 return -ENOMEM;
 468
 469         /* Send the packet to the ieee80211 layer for tx */
 470         ieee80211_tx_frame(mac->ieee, (struct ieee80211_hdr *) pkt, pkt_size);
 471
 472         kfree(pkt);
 473         return 0;
 474 }