drivers/net/wireless/hostap/hostap_80211_tx.c

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