drivers/net/wireless/hostap/hostap_80211_tx.c

   1 #include <linux/slab.h>
   2 #include <linux/export.h>
   3
   4 #include "hostap_80211.h"
   5 #include "hostap_common.h"
   6 #include "hostap_wlan.h"
   7 #include "hostap.h"
   8 #include "hostap_ap.h"
   9
  10 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
  11 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
  12 static unsigned char rfc1042_header[] =
  13 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
  14 /* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */
  15 static unsigned char bridge_tunnel_header[] =
  16 { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 };
  17 /* No encapsulation header if EtherType < 0x600 (=length) */
  18
  19 void hostap_dump_tx_80211(const char *name, struct sk_buff *skb)
  20 {
  21         struct ieee80211_hdr *hdr;
  22         u16 fc;
  23
  24         hdr = (struct ieee80211_hdr *) skb->data;
  25
  26         printk(KERN_DEBUG "%s: TX len=%d jiffies=%ld\n",
  27                name, skb->len, jiffies);
  28
  29         if (skb->len < 2)
  30                 return;
  31
  32         fc = le16_to_cpu(hdr->frame_control);
  33         printk(KERN_DEBUG "   FC=0x%04x (type=%d:%d)%s%s",
  34                fc, (fc & IEEE80211_FCTL_FTYPE) >> 2,
  35                (fc & IEEE80211_FCTL_STYPE) >> 4,
  36                fc & IEEE80211_FCTL_TODS ? " [ToDS]" : "",
  37                fc & IEEE80211_FCTL_FROMDS ? " [FromDS]" : "");
  38
  39         if (skb->len < IEEE80211_DATA_HDR3_LEN) {
  40                 printk("\n");
  41                 return;
  42         }
  43
  44         printk(" dur=0x%04x seq=0x%04x\n", le16_to_cpu(hdr->duration_id),
  45                le16_to_cpu(hdr->seq_ctrl));
  46
  47         printk(KERN_DEBUG "   A1=%pM", hdr->addr1);
  48         printk(" A2=%pM", hdr->addr2);
  49         printk(" A3=%pM", hdr->addr3);
  50         if (skb->len >= 30)
  51                 printk(" A4=%pM", hdr->addr4);
  52         printk("\n");
  53 }
  54
  55
  56 /* hard_start_xmit function for data interfaces (wlan#, wlan#wds#, wlan#sta)
  57  * Convert Ethernet header into a suitable IEEE 802.11 header depending on
  58  * device configuration. */
  59 netdev_tx_t hostap_data_start_xmit(struct sk_buff *skb,
  60                                    struct net_device *dev)
  61 {
  62         struct hostap_interface *iface;
  63         local_info_t *local;
  64         int need_headroom, need_tailroom = 0;
  65         struct ieee80211_hdr hdr;
  66         u16 fc, ethertype = 0;
  67         enum {
  68                 WDS_NO = 0, WDS_OWN_FRAME, WDS_COMPLIANT_FRAME
  69         } use_wds = WDS_NO;
  70         u8 *encaps_data;
  71         int hdr_len, encaps_len, skip_header_bytes;
  72         int to_assoc_ap = 0;
  73         struct hostap_skb_tx_data *meta;
  74
  75         iface = netdev_priv(dev);
  76         local = iface->local;
  77
  78         if (skb->len < ETH_HLEN) {
  79                 printk(KERN_DEBUG "%s: hostap_data_start_xmit: short skb "
  80                        "(len=%d)\n", dev->name, skb->len);
  81                 kfree_skb(skb);
  82                 return NETDEV_TX_OK;
  83         }
  84
  85         if (local->ddev != dev) {
  86                 use_wds = (local->iw_mode == IW_MODE_MASTER &&
  87                            !(local->wds_type & HOSTAP_WDS_STANDARD_FRAME)) ?
  88                         WDS_OWN_FRAME : WDS_COMPLIANT_FRAME;
  89                 if (dev == local->stadev) {
  90                         to_assoc_ap = 1;
  91                         use_wds = WDS_NO;
  92                 } else if (dev == local->apdev) {
  93                         printk(KERN_DEBUG "%s: prism2_tx: trying to use "
  94                                "AP device with Ethernet net dev\n", dev->name);
  95                         kfree_skb(skb);
  96                         return NETDEV_TX_OK;
  97                 }
  98         } else {
  99                 if (local->iw_mode == IW_MODE_REPEAT) {
 100                         printk(KERN_DEBUG "%s: prism2_tx: trying to use "
 101                                "non-WDS link in Repeater mode\n", dev->name);
 102                         kfree_skb(skb);
 103                         return NETDEV_TX_OK;
 104                 } else if (local->iw_mode == IW_MODE_INFRA &&
 105                            (local->wds_type & HOSTAP_WDS_AP_CLIENT) &&
 106                            memcmp(skb->data + ETH_ALEN, dev->dev_addr,
 107                                   ETH_ALEN) != 0) {
 108                         /* AP client mode: send frames with foreign src addr
 109                          * using 4-addr WDS frames */
 110                         use_wds = WDS_COMPLIANT_FRAME;
 111                 }
 112         }
 113
 114         /* Incoming skb->data: dst_addr[6], src_addr[6], proto[2], payload
 115          * ==>
 116          * Prism2 TX frame with 802.11 header:
 117          * txdesc (address order depending on used mode; includes dst_addr and
 118          * src_addr), possible encapsulation (RFC1042/Bridge-Tunnel;
 119          * proto[2], payload {, possible addr4[6]} */
 120
 121         ethertype = (skb->data[12] << 8) | skb->data[13];
 122
 123         memset(&hdr, 0, sizeof(hdr));
 124
 125         /* Length of data after IEEE 802.11 header */
 126         encaps_data = NULL;
 127         encaps_len = 0;
 128         skip_header_bytes = ETH_HLEN;
 129         if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
 130                 encaps_data = bridge_tunnel_header;
 131                 encaps_len = sizeof(bridge_tunnel_header);
 132                 skip_header_bytes -= 2;
 133         } else if (ethertype >= 0x600) {
 134                 encaps_data = rfc1042_header;
 135                 encaps_len = sizeof(rfc1042_header);
 136                 skip_header_bytes -= 2;
 137         }
 138
 139         fc = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA;
 140         hdr_len = IEEE80211_DATA_HDR3_LEN;
 141
 142         if (use_wds != WDS_NO) {
 143                 /* Note! Prism2 station firmware has problems with sending real
 144                  * 802.11 frames with four addresses; until these problems can
 145                  * be fixed or worked around, 4-addr frames needed for WDS are
 146                  * using incompatible format: FromDS flag is not set and the
 147                  * fourth address is added after the frame payload; it is
 148                  * assumed, that the receiving station knows how to handle this
 149                  * frame format */
 150
 151                 if (use_wds == WDS_COMPLIANT_FRAME) {
 152                         fc |= IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS;
 153                         /* From&To DS: Addr1 = RA, Addr2 = TA, Addr3 = DA,
 154                          * Addr4 = SA */
 155                         skb_copy_from_linear_data_offset(skb, ETH_ALEN,
 156                                                          &hdr.addr4, ETH_ALEN);
 157                         hdr_len += ETH_ALEN;
 158                 } else {
 159                         /* bogus 4-addr format to workaround Prism2 station
 160                          * f/w bug */
 161                         fc |= IEEE80211_FCTL_TODS;
 162                         /* From DS: Addr1 = DA (used as RA),
 163                          * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA),
 164                          */
 165
 166                         /* SA from skb->data + ETH_ALEN will be added after
 167                          * frame payload; use hdr.addr4 as a temporary buffer
 168                          */
 169                         skb_copy_from_linear_data_offset(skb, ETH_ALEN,
 170                                                          &hdr.addr4, ETH_ALEN);
 171                         need_tailroom += ETH_ALEN;
 172                 }
 173
 174                 /* send broadcast and multicast frames to broadcast RA, if
 175                  * configured; otherwise, use unicast RA of the WDS link */
 176                 if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) &&
 177                     skb->data[0] & 0x01)
 178                         memset(&hdr.addr1, 0xff, ETH_ALEN);
 179                 else if (iface->type == HOSTAP_INTERFACE_WDS)
 180                         memcpy(&hdr.addr1, iface->u.wds.remote_addr,
 181                                ETH_ALEN);
 182                 else
 183                         memcpy(&hdr.addr1, local->bssid, ETH_ALEN);
 184                 memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
 185                 skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
 186         } else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) {
 187                 fc |= IEEE80211_FCTL_FROMDS;
 188                 /* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */
 189                 skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
 190                 memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN);
 191                 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr3,
 192                                                  ETH_ALEN);
 193         } else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) {
 194                 fc |= IEEE80211_FCTL_TODS;
 195                 /* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */
 196                 memcpy(&hdr.addr1, to_assoc_ap ?
 197                        local->assoc_ap_addr : local->bssid, ETH_ALEN);
 198                 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
 199                                                  ETH_ALEN);
 200                 skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN);
 201         } else if (local->iw_mode == IW_MODE_ADHOC) {
 202                 /* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */
 203                 skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN);
 204                 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2,
 205                                                  ETH_ALEN);
 206                 memcpy(&hdr.addr3, local->bssid, ETH_ALEN);
 207         }
 208
 209         hdr.frame_control = cpu_to_le16(fc);
 210
 211         skb_pull(skb, skip_header_bytes);
 212         need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len;
 213         if (skb_tailroom(skb) < need_tailroom) {
 214                 skb = skb_unshare(skb, GFP_ATOMIC);
 215                 if (skb == NULL) {
 216                         iface->stats.tx_dropped++;
 217                         return NETDEV_TX_OK;
 218                 }
 219                 if (pskb_expand_head(skb, need_headroom, need_tailroom,
 220                                      GFP_ATOMIC)) {
 221                         kfree_skb(skb);
 222                         iface->stats.tx_dropped++;
 223                         return NETDEV_TX_OK;
 224                 }
 225         } else if (skb_headroom(skb) < need_headroom) {
 226                 struct sk_buff *tmp = skb;
 227                 skb = skb_realloc_headroom(skb, need_headroom);
 228                 kfree_skb(tmp);
 229                 if (skb == NULL) {
 230                         iface->stats.tx_dropped++;
 231                         return NETDEV_TX_OK;
 232                 }
 233         } else {
 234                 skb = skb_unshare(skb, GFP_ATOMIC);
 235                 if (skb == NULL) {
 236                         iface->stats.tx_dropped++;
 237                         return NETDEV_TX_OK;
 238                 }
 239         }
 240
 241         if (encaps_data)
 242                 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
 243         memcpy(skb_push(skb, hdr_len), &hdr, hdr_len);
 244         if (use_wds == WDS_OWN_FRAME) {
 245                 memcpy(skb_put(skb, ETH_ALEN), &hdr.addr4, ETH_ALEN);
 246         }
 247
 248         iface->stats.tx_packets++;
 249         iface->stats.tx_bytes += skb->len;
 250
 251         skb_reset_mac_header(skb);
 252         meta = (struct hostap_skb_tx_data *) skb->cb;
 253         memset(meta, 0, sizeof(*meta));
 254         meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
 255         if (use_wds)
 256                 meta->flags |= HOSTAP_TX_FLAGS_WDS;
 257         meta->ethertype = ethertype;
 258         meta->iface = iface;
 259
 260         /* Send IEEE 802.11 encapsulated frame using the master radio device */
 261         skb->dev = local->dev;
 262         dev_queue_xmit(skb);
 263         return NETDEV_TX_OK;
 264 }
 265
 266
 267 /* hard_start_xmit function for hostapd wlan#ap interfaces */
 268 netdev_tx_t hostap_mgmt_start_xmit(struct sk_buff *skb,
 269                                    struct net_device *dev)
 270 {
 271         struct hostap_interface *iface;
 272         local_info_t *local;
 273         struct hostap_skb_tx_data *meta;
 274         struct ieee80211_hdr *hdr;
 275         u16 fc;
 276
 277         iface = netdev_priv(dev);
 278         local = iface->local;
 279
 280         if (skb->len < 10) {
 281                 printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb "
 282                        "(len=%d)\n", dev->name, skb->len);
 283                 kfree_skb(skb);
 284                 return NETDEV_TX_OK;
 285         }
 286
 287         iface->stats.tx_packets++;
 288         iface->stats.tx_bytes += skb->len;
 289
 290         meta = (struct hostap_skb_tx_data *) skb->cb;
 291         memset(meta, 0, sizeof(*meta));
 292         meta->magic = HOSTAP_SKB_TX_DATA_MAGIC;
 293         meta->iface = iface;
 294
 295         if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) {
 296                 hdr = (struct ieee80211_hdr *) skb->data;
 297                 fc = le16_to_cpu(hdr->frame_control);
 298                 if (ieee80211_is_data(hdr->frame_control) &&
 299                     (fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_DATA) {
 300                         u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN +
 301                                              sizeof(rfc1042_header)];
 302                         meta->ethertype = (pos[0] << 8) | pos[1];
 303                 }
 304         }
 305
 306         /* Send IEEE 802.11 encapsulated frame using the master radio device */
 307         skb->dev = local->dev;
 308         dev_queue_xmit(skb);
 309         return NETDEV_TX_OK;
 310 }
 311
 312
 313 /* Called only from software IRQ */
 314 static struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb,
 315                                           struct lib80211_crypt_data *crypt)
 316 {
 317         struct hostap_interface *iface;
 318         local_info_t *local;
 319         struct ieee80211_hdr *hdr;
 320         int prefix_len, postfix_len, hdr_len, res;
 321
 322         iface = netdev_priv(skb->dev);
 323         local = iface->local;
 324
 325         if (skb->len < IEEE80211_DATA_HDR3_LEN) {
 326                 kfree_skb(skb);
 327                 return NULL;
 328         }
 329
 330         if (local->tkip_countermeasures &&
 331             strcmp(crypt->ops->name, "TKIP") == 0) {
 332                 hdr = (struct ieee80211_hdr *) skb->data;
 333                 if (net_ratelimit()) {
 334                         printk(KERN_DEBUG "%s: TKIP countermeasures: dropped "
 335                                "TX packet to %pM\n",
 336                                local->dev->name, hdr->addr1);
 337                 }
 338                 kfree_skb(skb);
 339                 return NULL;
 340         }
 341
 342         skb = skb_unshare(skb, GFP_ATOMIC);
 343         if (skb == NULL)
 344                 return NULL;
 345
 346         prefix_len = crypt->ops->extra_mpdu_prefix_len +
 347                 crypt->ops->extra_msdu_prefix_len;
 348         postfix_len = crypt->ops->extra_mpdu_postfix_len +
 349                 crypt->ops->extra_msdu_postfix_len;
 350         if ((skb_headroom(skb) < prefix_len ||
 351              skb_tailroom(skb) < postfix_len) &&
 352             pskb_expand_head(skb, prefix_len, postfix_len, GFP_ATOMIC)) {
 353                 kfree_skb(skb);
 354                 return NULL;
 355         }
 356
 357         hdr = (struct ieee80211_hdr *) skb->data;
 358         hdr_len = hostap_80211_get_hdrlen(hdr->frame_control);
 359
 360         /* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so
 361          * call both MSDU and MPDU encryption functions from here. */
 362         atomic_inc(&crypt->refcnt);
 363         res = 0;
 364         if (crypt->ops->encrypt_msdu)
 365                 res = crypt->ops->encrypt_msdu(skb, hdr_len, crypt->priv);
 366         if (res == 0 && crypt->ops->encrypt_mpdu)
 367                 res = crypt->ops->encrypt_mpdu(skb, hdr_len, crypt->priv);
 368         atomic_dec(&crypt->refcnt);
 369         if (res < 0) {
 370                 kfree_skb(skb);
 371                 return NULL;
 372         }
 373
 374         return skb;
 375 }
 376
 377
 378 /* hard_start_xmit function for master radio interface wifi#.
 379  * AP processing (TX rate control, power save buffering, etc.).
 380  * Use hardware TX function to send the frame. */
 381 netdev_tx_t hostap_master_start_xmit(struct sk_buff *skb,
 382                                      struct net_device *dev)
 383 {
 384         struct hostap_interface *iface;
 385         local_info_t *local;
 386         netdev_tx_t ret = NETDEV_TX_BUSY;
 387         u16 fc;
 388         struct hostap_tx_data tx;
 389         ap_tx_ret tx_ret;
 390         struct hostap_skb_tx_data *meta;
 391         int no_encrypt = 0;
 392         struct ieee80211_hdr *hdr;
 393
 394         iface = netdev_priv(dev);
 395         local = iface->local;
 396
 397         tx.skb = skb;
 398         tx.sta_ptr = NULL;
 399
 400         meta = (struct hostap_skb_tx_data *) skb->cb;
 401         if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
 402                 printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
 403                        "expected 0x%08x)\n",
 404                        dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC);
 405                 ret = NETDEV_TX_OK;
 406                 iface->stats.tx_dropped++;
 407                 goto fail;
 408         }
 409
 410         if (local->host_encrypt) {
 411                 /* Set crypt to default algorithm and key; will be replaced in
 412                  * AP code if STA has own alg/key */
 413                 tx.crypt = local->crypt_info.crypt[local->crypt_info.tx_keyidx];
 414                 tx.host_encrypt = 1;
 415         } else {
 416                 tx.crypt = NULL;
 417                 tx.host_encrypt = 0;
 418         }
 419
 420         if (skb->len < 24) {
 421                 printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb "
 422                        "(len=%d)\n", dev->name, skb->len);
 423                 ret = NETDEV_TX_OK;
 424                 iface->stats.tx_dropped++;
 425                 goto fail;
 426         }
 427
 428         /* FIX (?):
 429          * Wi-Fi 802.11b test plan suggests that AP should ignore power save
 430          * bit in authentication and (re)association frames and assume tha
 431          * STA remains awake for the response. */
 432         tx_ret = hostap_handle_sta_tx(local, &tx);
 433         skb = tx.skb;
 434         meta = (struct hostap_skb_tx_data *) skb->cb;
 435         hdr = (struct ieee80211_hdr *) skb->data;
 436         fc = le16_to_cpu(hdr->frame_control);
 437         switch (tx_ret) {
 438         case AP_TX_CONTINUE:
 439                 break;
 440         case AP_TX_CONTINUE_NOT_AUTHORIZED:
 441                 if (local->ieee_802_1x &&
 442                     ieee80211_is_data(hdr->frame_control) &&
 443                     meta->ethertype != ETH_P_PAE &&
 444                     !(meta->flags & HOSTAP_TX_FLAGS_WDS)) {
 445                         printk(KERN_DEBUG "%s: dropped frame to unauthorized "
 446                                "port (IEEE 802.1X): ethertype=0x%04x\n",
 447                                dev->name, meta->ethertype);
 448                         hostap_dump_tx_80211(dev->name, skb);
 449
 450                         ret = NETDEV_TX_OK; /* drop packet */
 451                         iface->stats.tx_dropped++;
 452                         goto fail;
 453                 }
 454                 break;
 455         case AP_TX_DROP:
 456                 ret = NETDEV_TX_OK; /* drop packet */
 457                 iface->stats.tx_dropped++;
 458                 goto fail;
 459         case AP_TX_RETRY:
 460                 goto fail;
 461         case AP_TX_BUFFERED:
 462                 /* do not free skb here, it will be freed when the
 463                  * buffered frame is sent/timed out */
 464                 ret = NETDEV_TX_OK;
 465                 goto tx_exit;
 466         }
 467
 468         /* Request TX callback if protocol version is 2 in 802.11 header;
 469          * this version 2 is a special case used between hostapd and kernel
 470          * driver */
 471         if (((fc & IEEE80211_FCTL_VERS) == BIT(1)) &&
 472             local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) {
 473                 meta->tx_cb_idx = local->ap->tx_callback_idx;
 474
 475                 /* remove special version from the frame header */
 476                 fc &= ~IEEE80211_FCTL_VERS;
 477                 hdr->frame_control = cpu_to_le16(fc);
 478         }
 479
 480         if (!ieee80211_is_data(hdr->frame_control)) {
 481                 no_encrypt = 1;
 482                 tx.crypt = NULL;
 483         }
 484
 485         if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt &&
 486             !(fc & IEEE80211_FCTL_PROTECTED)) {
 487                 no_encrypt = 1;
 488                 PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing "
 489                        "unencrypted EAPOL frame\n", dev->name);
 490                 tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */
 491         }
 492
 493         if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu))
 494                 tx.crypt = NULL;
 495         else if ((tx.crypt ||
 496                  local->crypt_info.crypt[local->crypt_info.tx_keyidx]) &&
 497                  !no_encrypt) {
 498                 /* Add ISWEP flag both for firmware and host based encryption
 499                  */
 500                 fc |= IEEE80211_FCTL_PROTECTED;
 501                 hdr->frame_control = cpu_to_le16(fc);
 502         } else if (local->drop_unencrypted &&
 503                    ieee80211_is_data(hdr->frame_control) &&
 504                    meta->ethertype != ETH_P_PAE) {
 505                 if (net_ratelimit()) {
 506                         printk(KERN_DEBUG "%s: dropped unencrypted TX data "
 507                                "frame (drop_unencrypted=1)\n", dev->name);
 508                 }
 509                 iface->stats.tx_dropped++;
 510                 ret = NETDEV_TX_OK;
 511                 goto fail;
 512         }
 513
 514         if (tx.crypt) {
 515                 skb = hostap_tx_encrypt(skb, tx.crypt);
 516                 if (skb == NULL) {
 517                         printk(KERN_DEBUG "%s: TX - encryption failed\n",
 518                                dev->name);
 519                         ret = NETDEV_TX_OK;
 520                         goto fail;
 521                 }
 522                 meta = (struct hostap_skb_tx_data *) skb->cb;
 523                 if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) {
 524                         printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, "
 525                                "expected 0x%08x) after hostap_tx_encrypt\n",
 526                                dev->name, meta->magic,
 527                                HOSTAP_SKB_TX_DATA_MAGIC);
 528                         ret = NETDEV_TX_OK;
 529                         iface->stats.tx_dropped++;
 530                         goto fail;
 531                 }
 532         }
 533
 534         if (local->func->tx == NULL || local->func->tx(skb, dev)) {
 535                 ret = NETDEV_TX_OK;
 536                 iface->stats.tx_dropped++;
 537         } else {
 538                 ret = NETDEV_TX_OK;
 539                 iface->stats.tx_packets++;
 540                 iface->stats.tx_bytes += skb->len;
 541         }
 542
 543  fail:
 544         if (ret == NETDEV_TX_OK && skb)
 545                 dev_kfree_skb(skb);
 546  tx_exit:
 547         if (tx.sta_ptr)
 548                 hostap_handle_sta_release(tx.sta_ptr);
 549         return ret;
 550 }
 551
 552
 553 EXPORT_SYMBOL(hostap_master_start_xmit);