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) */ 11static unsigned char rfc1042_header[] = 12{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 }; 13/* Bridge-Tunnel header (for EtherTypes ETH_P_AARP and ETH_P_IPX) */ 14static unsigned char bridge_tunnel_header[] = 15{ 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 }; 16/* No encapsulation header if EtherType < 0x600 (=length) */ 17 18void 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. */ 58netdev_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 fc |= IEEE80211_FCTL_TODS; 159 /* From DS: Addr1 = DA (used as RA), 160 * Addr2 = BSSID (used as TA), Addr3 = SA (used as DA), 161 */ 162 163 /* SA from skb->data + ETH_ALEN will be added after 164 * frame payload; use hdr.addr4 as a temporary buffer 165 */ 166 skb_copy_from_linear_data_offset(skb, ETH_ALEN, 167 &hdr.addr4, ETH_ALEN); 168 need_tailroom += ETH_ALEN; 169 } 170 171 /* send broadcast and multicast frames to broadcast RA, if 172 * configured; otherwise, use unicast RA of the WDS link */ 173 if ((local->wds_type & HOSTAP_WDS_BROADCAST_RA) && 174 skb->data[0] & 0x01) 175 memset(&hdr.addr1, 0xff, ETH_ALEN); 176 else if (iface->type == HOSTAP_INTERFACE_WDS) 177 memcpy(&hdr.addr1, iface->u.wds.remote_addr, 178 ETH_ALEN); 179 else 180 memcpy(&hdr.addr1, local->bssid, ETH_ALEN); 181 memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN); 182 skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN); 183 } else if (local->iw_mode == IW_MODE_MASTER && !to_assoc_ap) { 184 fc |= IEEE80211_FCTL_FROMDS; 185 /* From DS: Addr1 = DA, Addr2 = BSSID, Addr3 = SA */ 186 skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN); 187 memcpy(&hdr.addr2, dev->dev_addr, ETH_ALEN); 188 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr3, 189 ETH_ALEN); 190 } else if (local->iw_mode == IW_MODE_INFRA || to_assoc_ap) { 191 fc |= IEEE80211_FCTL_TODS; 192 /* To DS: Addr1 = BSSID, Addr2 = SA, Addr3 = DA */ 193 memcpy(&hdr.addr1, to_assoc_ap ? 194 local->assoc_ap_addr : local->bssid, ETH_ALEN); 195 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2, 196 ETH_ALEN); 197 skb_copy_from_linear_data(skb, &hdr.addr3, ETH_ALEN); 198 } else if (local->iw_mode == IW_MODE_ADHOC) { 199 /* not From/To DS: Addr1 = DA, Addr2 = SA, Addr3 = BSSID */ 200 skb_copy_from_linear_data(skb, &hdr.addr1, ETH_ALEN); 201 skb_copy_from_linear_data_offset(skb, ETH_ALEN, &hdr.addr2, 202 ETH_ALEN); 203 memcpy(&hdr.addr3, local->bssid, ETH_ALEN); 204 } 205 206 hdr.frame_control = cpu_to_le16(fc); 207 208 skb_pull(skb, skip_header_bytes); 209 need_headroom = local->func->need_tx_headroom + hdr_len + encaps_len; 210 if (skb_tailroom(skb) < need_tailroom) { 211 skb = skb_unshare(skb, GFP_ATOMIC); 212 if (skb == NULL) { 213 iface->stats.tx_dropped++; 214 return NETDEV_TX_OK; 215 } 216 if (pskb_expand_head(skb, need_headroom, need_tailroom, 217 GFP_ATOMIC)) { 218 kfree_skb(skb); 219 iface->stats.tx_dropped++; 220 return NETDEV_TX_OK; 221 } 222 } else if (skb_headroom(skb) < need_headroom) { 223 struct sk_buff *tmp = skb; 224 skb = skb_realloc_headroom(skb, need_headroom); 225 kfree_skb(tmp); 226 if (skb == NULL) { 227 iface->stats.tx_dropped++; 228 return NETDEV_TX_OK; 229 } 230 } else { 231 skb = skb_unshare(skb, GFP_ATOMIC); 232 if (skb == NULL) { 233 iface->stats.tx_dropped++; 234 return NETDEV_TX_OK; 235 } 236 } 237 238 if (encaps_data) 239 memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len); 240 memcpy(skb_push(skb, hdr_len), &hdr, hdr_len); 241 if (use_wds == WDS_OWN_FRAME) { 242 memcpy(skb_put(skb, ETH_ALEN), &hdr.addr4, ETH_ALEN); 243 } 244 245 iface->stats.tx_packets++; 246 iface->stats.tx_bytes += skb->len; 247 248 skb_reset_mac_header(skb); 249 meta = (struct hostap_skb_tx_data *) skb->cb; 250 memset(meta, 0, sizeof(*meta)); 251 meta->magic = HOSTAP_SKB_TX_DATA_MAGIC; 252 if (use_wds) 253 meta->flags |= HOSTAP_TX_FLAGS_WDS; 254 meta->ethertype = ethertype; 255 meta->iface = iface; 256 257 /* Send IEEE 802.11 encapsulated frame using the master radio device */ 258 skb->dev = local->dev; 259 dev_queue_xmit(skb); 260 return NETDEV_TX_OK; 261} 262 263 264/* hard_start_xmit function for hostapd wlan#ap interfaces */ 265netdev_tx_t hostap_mgmt_start_xmit(struct sk_buff *skb, 266 struct net_device *dev) 267{ 268 struct hostap_interface *iface; 269 local_info_t *local; 270 struct hostap_skb_tx_data *meta; 271 struct ieee80211_hdr *hdr; 272 u16 fc; 273 274 iface = netdev_priv(dev); 275 local = iface->local; 276 277 if (skb->len < 10) { 278 printk(KERN_DEBUG "%s: hostap_mgmt_start_xmit: short skb " 279 "(len=%d)\n", dev->name, skb->len); 280 kfree_skb(skb); 281 return NETDEV_TX_OK; 282 } 283 284 iface->stats.tx_packets++; 285 iface->stats.tx_bytes += skb->len; 286 287 meta = (struct hostap_skb_tx_data *) skb->cb; 288 memset(meta, 0, sizeof(*meta)); 289 meta->magic = HOSTAP_SKB_TX_DATA_MAGIC; 290 meta->iface = iface; 291 292 if (skb->len >= IEEE80211_DATA_HDR3_LEN + sizeof(rfc1042_header) + 2) { 293 hdr = (struct ieee80211_hdr *) skb->data; 294 fc = le16_to_cpu(hdr->frame_control); 295 if (ieee80211_is_data(hdr->frame_control) && 296 (fc & IEEE80211_FCTL_STYPE) == IEEE80211_STYPE_DATA) { 297 u8 *pos = &skb->data[IEEE80211_DATA_HDR3_LEN + 298 sizeof(rfc1042_header)]; 299 meta->ethertype = (pos[0] << 8) | pos[1]; 300 } 301 } 302 303 /* Send IEEE 802.11 encapsulated frame using the master radio device */ 304 skb->dev = local->dev; 305 dev_queue_xmit(skb); 306 return NETDEV_TX_OK; 307} 308 309 310/* Called only from software IRQ */ 311static struct sk_buff * hostap_tx_encrypt(struct sk_buff *skb, 312 struct lib80211_crypt_data *crypt) 313{ 314 struct hostap_interface *iface; 315 local_info_t *local; 316 struct ieee80211_hdr *hdr; 317 int prefix_len, postfix_len, hdr_len, res; 318 319 iface = netdev_priv(skb->dev); 320 local = iface->local; 321 322 if (skb->len < IEEE80211_DATA_HDR3_LEN) { 323 kfree_skb(skb); 324 return NULL; 325 } 326 327 if (local->tkip_countermeasures && 328 strcmp(crypt->ops->name, "TKIP") == 0) { 329 hdr = (struct ieee80211_hdr *) skb->data; 330 if (net_ratelimit()) { 331 printk(KERN_DEBUG "%s: TKIP countermeasures: dropped " 332 "TX packet to %pM\n", 333 local->dev->name, hdr->addr1); 334 } 335 kfree_skb(skb); 336 return NULL; 337 } 338 339 skb = skb_unshare(skb, GFP_ATOMIC); 340 if (skb == NULL) 341 return NULL; 342 343 prefix_len = crypt->ops->extra_mpdu_prefix_len + 344 crypt->ops->extra_msdu_prefix_len; 345 postfix_len = crypt->ops->extra_mpdu_postfix_len + 346 crypt->ops->extra_msdu_postfix_len; 347 if ((skb_headroom(skb) < prefix_len || 348 skb_tailroom(skb) < postfix_len) && 349 pskb_expand_head(skb, prefix_len, postfix_len, GFP_ATOMIC)) { 350 kfree_skb(skb); 351 return NULL; 352 } 353 354 hdr = (struct ieee80211_hdr *) skb->data; 355 hdr_len = hostap_80211_get_hdrlen(hdr->frame_control); 356 357 /* Host-based IEEE 802.11 fragmentation for TX is not yet supported, so 358 * call both MSDU and MPDU encryption functions from here. */ 359 atomic_inc(&crypt->refcnt); 360 res = 0; 361 if (crypt->ops->encrypt_msdu) 362 res = crypt->ops->encrypt_msdu(skb, hdr_len, crypt->priv); 363 if (res == 0 && crypt->ops->encrypt_mpdu) 364 res = crypt->ops->encrypt_mpdu(skb, hdr_len, crypt->priv); 365 atomic_dec(&crypt->refcnt); 366 if (res < 0) { 367 kfree_skb(skb); 368 return NULL; 369 } 370 371 return skb; 372} 373 374 375/* hard_start_xmit function for master radio interface wifi#. 376 * AP processing (TX rate control, power save buffering, etc.). 377 * Use hardware TX function to send the frame. */ 378netdev_tx_t hostap_master_start_xmit(struct sk_buff *skb, 379 struct net_device *dev) 380{ 381 struct hostap_interface *iface; 382 local_info_t *local; 383 netdev_tx_t ret = NETDEV_TX_BUSY; 384 u16 fc; 385 struct hostap_tx_data tx; 386 ap_tx_ret tx_ret; 387 struct hostap_skb_tx_data *meta; 388 int no_encrypt = 0; 389 struct ieee80211_hdr *hdr; 390 391 iface = netdev_priv(dev); 392 local = iface->local; 393 394 tx.skb = skb; 395 tx.sta_ptr = NULL; 396 397 meta = (struct hostap_skb_tx_data *) skb->cb; 398 if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) { 399 printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, " 400 "expected 0x%08x)\n", 401 dev->name, meta->magic, HOSTAP_SKB_TX_DATA_MAGIC); 402 ret = NETDEV_TX_OK; 403 iface->stats.tx_dropped++; 404 goto fail; 405 } 406 407 if (local->host_encrypt) { 408 /* Set crypt to default algorithm and key; will be replaced in 409 * AP code if STA has own alg/key */ 410 tx.crypt = local->crypt_info.crypt[local->crypt_info.tx_keyidx]; 411 tx.host_encrypt = 1; 412 } else { 413 tx.crypt = NULL; 414 tx.host_encrypt = 0; 415 } 416 417 if (skb->len < 24) { 418 printk(KERN_DEBUG "%s: hostap_master_start_xmit: short skb " 419 "(len=%d)\n", dev->name, skb->len); 420 ret = NETDEV_TX_OK; 421 iface->stats.tx_dropped++; 422 goto fail; 423 } 424 425 /* FIX (?): 426 * Wi-Fi 802.11b test plan suggests that AP should ignore power save 427 * bit in authentication and (re)association frames and assume tha 428 * STA remains awake for the response. */ 429 tx_ret = hostap_handle_sta_tx(local, &tx); 430 skb = tx.skb; 431 meta = (struct hostap_skb_tx_data *) skb->cb; 432 hdr = (struct ieee80211_hdr *) skb->data; 433 fc = le16_to_cpu(hdr->frame_control); 434 switch (tx_ret) { 435 case AP_TX_CONTINUE: 436 break; 437 case AP_TX_CONTINUE_NOT_AUTHORIZED: 438 if (local->ieee_802_1x && 439 ieee80211_is_data(hdr->frame_control) && 440 meta->ethertype != ETH_P_PAE && 441 !(meta->flags & HOSTAP_TX_FLAGS_WDS)) { 442 printk(KERN_DEBUG "%s: dropped frame to unauthorized " 443 "port (IEEE 802.1X): ethertype=0x%04x\n", 444 dev->name, meta->ethertype); 445 hostap_dump_tx_80211(dev->name, skb); 446 447 ret = NETDEV_TX_OK; /* drop packet */ 448 iface->stats.tx_dropped++; 449 goto fail; 450 } 451 break; 452 case AP_TX_DROP: 453 ret = NETDEV_TX_OK; /* drop packet */ 454 iface->stats.tx_dropped++; 455 goto fail; 456 case AP_TX_RETRY: 457 goto fail; 458 case AP_TX_BUFFERED: 459 /* do not free skb here, it will be freed when the 460 * buffered frame is sent/timed out */ 461 ret = NETDEV_TX_OK; 462 goto tx_exit; 463 } 464 465 /* Request TX callback if protocol version is 2 in 802.11 header; 466 * this version 2 is a special case used between hostapd and kernel 467 * driver */ 468 if (((fc & IEEE80211_FCTL_VERS) == BIT(1)) && 469 local->ap && local->ap->tx_callback_idx && meta->tx_cb_idx == 0) { 470 meta->tx_cb_idx = local->ap->tx_callback_idx; 471 472 /* remove special version from the frame header */ 473 fc &= ~IEEE80211_FCTL_VERS; 474 hdr->frame_control = cpu_to_le16(fc); 475 } 476 477 if (!ieee80211_is_data(hdr->frame_control)) { 478 no_encrypt = 1; 479 tx.crypt = NULL; 480 } 481 482 if (local->ieee_802_1x && meta->ethertype == ETH_P_PAE && tx.crypt && 483 !(fc & IEEE80211_FCTL_PROTECTED)) { 484 no_encrypt = 1; 485 PDEBUG(DEBUG_EXTRA2, "%s: TX: IEEE 802.1X - passing " 486 "unencrypted EAPOL frame\n", dev->name); 487 tx.crypt = NULL; /* no encryption for IEEE 802.1X frames */ 488 } 489 490 if (tx.crypt && (!tx.crypt->ops || !tx.crypt->ops->encrypt_mpdu)) 491 tx.crypt = NULL; 492 else if ((tx.crypt || 493 local->crypt_info.crypt[local->crypt_info.tx_keyidx]) && 494 !no_encrypt) { 495 /* Add ISWEP flag both for firmware and host based encryption 496 */ 497 fc |= IEEE80211_FCTL_PROTECTED; 498 hdr->frame_control = cpu_to_le16(fc); 499 } else if (local->drop_unencrypted && 500 ieee80211_is_data(hdr->frame_control) && 501 meta->ethertype != ETH_P_PAE) { 502 if (net_ratelimit()) { 503 printk(KERN_DEBUG "%s: dropped unencrypted TX data " 504 "frame (drop_unencrypted=1)\n", dev->name); 505 } 506 iface->stats.tx_dropped++; 507 ret = NETDEV_TX_OK; 508 goto fail; 509 } 510 511 if (tx.crypt) { 512 skb = hostap_tx_encrypt(skb, tx.crypt); 513 if (skb == NULL) { 514 printk(KERN_DEBUG "%s: TX - encryption failed\n", 515 dev->name); 516 ret = NETDEV_TX_OK; 517 goto fail; 518 } 519 meta = (struct hostap_skb_tx_data *) skb->cb; 520 if (meta->magic != HOSTAP_SKB_TX_DATA_MAGIC) { 521 printk(KERN_DEBUG "%s: invalid skb->cb magic (0x%08x, " 522 "expected 0x%08x) after hostap_tx_encrypt\n", 523 dev->name, meta->magic, 524 HOSTAP_SKB_TX_DATA_MAGIC); 525 ret = NETDEV_TX_OK; 526 iface->stats.tx_dropped++; 527 goto fail; 528 } 529 } 530 531 if (local->func->tx == NULL || local->func->tx(skb, dev)) { 532 ret = NETDEV_TX_OK; 533 iface->stats.tx_dropped++; 534 } else { 535 ret = NETDEV_TX_OK; 536 iface->stats.tx_packets++; 537 iface->stats.tx_bytes += skb->len; 538 } 539 540 fail: 541 if (ret == NETDEV_TX_OK && skb) 542 dev_kfree_skb(skb); 543 tx_exit: 544 if (tx.sta_ptr) 545 hostap_handle_sta_release(tx.sta_ptr); 546 return ret; 547} 548 549 550EXPORT_SYMBOL(hostap_master_start_xmit); 551