1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * NXP Wireless LAN device driver: AP TX and RX data handling
4  *
5  * Copyright 2011-2020 NXP
6  */
7 
8 #include "decl.h"
9 #include "ioctl.h"
10 #include "main.h"
11 #include "wmm.h"
12 #include "11n_aggr.h"
13 #include "11n_rxreorder.h"
14 
15 /* This function checks if particular RA list has packets more than low bridge
16  * packet threshold and then deletes packet from this RA list.
17  * Function deletes packets from such RA list and returns true. If no such list
18  * is found, false is returned.
19  */
20 static bool
21 mwifiex_uap_del_tx_pkts_in_ralist(struct mwifiex_private *priv,
22 				  struct list_head *ra_list_head,
23 				  int tid)
24 {
25 	struct mwifiex_ra_list_tbl *ra_list;
26 	struct sk_buff *skb, *tmp;
27 	bool pkt_deleted = false;
28 	struct mwifiex_txinfo *tx_info;
29 	struct mwifiex_adapter *adapter = priv->adapter;
30 
31 	list_for_each_entry(ra_list, ra_list_head, list) {
32 		if (skb_queue_empty(&ra_list->skb_head))
33 			continue;
34 
35 		skb_queue_walk_safe(&ra_list->skb_head, skb, tmp) {
36 			tx_info = MWIFIEX_SKB_TXCB(skb);
37 			if (tx_info->flags & MWIFIEX_BUF_FLAG_BRIDGED_PKT) {
38 				__skb_unlink(skb, &ra_list->skb_head);
39 				mwifiex_write_data_complete(adapter, skb, 0,
40 							    -1);
41 				if (ra_list->tx_paused)
42 					priv->wmm.pkts_paused[tid]--;
43 				else
44 					atomic_dec(&priv->wmm.tx_pkts_queued);
45 				pkt_deleted = true;
46 			}
47 			if ((atomic_read(&adapter->pending_bridged_pkts) <=
48 					     MWIFIEX_BRIDGED_PKTS_THR_LOW))
49 				break;
50 		}
51 	}
52 
53 	return pkt_deleted;
54 }
55 
56 /* This function deletes packets from particular RA List. RA list index
57  * from which packets are deleted is preserved so that packets from next RA
58  * list are deleted upon subsequent call thus maintaining fairness.
59  */
60 static void mwifiex_uap_cleanup_tx_queues(struct mwifiex_private *priv)
61 {
62 	struct list_head *ra_list;
63 	int i;
64 
65 	spin_lock_bh(&priv->wmm.ra_list_spinlock);
66 
67 	for (i = 0; i < MAX_NUM_TID; i++, priv->del_list_idx++) {
68 		if (priv->del_list_idx == MAX_NUM_TID)
69 			priv->del_list_idx = 0;
70 		ra_list = &priv->wmm.tid_tbl_ptr[priv->del_list_idx].ra_list;
71 		if (mwifiex_uap_del_tx_pkts_in_ralist(priv, ra_list, i)) {
72 			priv->del_list_idx++;
73 			break;
74 		}
75 	}
76 
77 	spin_unlock_bh(&priv->wmm.ra_list_spinlock);
78 }
79 
80 
81 static void mwifiex_uap_queue_bridged_pkt(struct mwifiex_private *priv,
82 					 struct sk_buff *skb)
83 {
84 	struct mwifiex_adapter *adapter = priv->adapter;
85 	struct uap_rxpd *uap_rx_pd;
86 	struct rx_packet_hdr *rx_pkt_hdr;
87 	struct sk_buff *new_skb;
88 	struct mwifiex_txinfo *tx_info;
89 	int hdr_chop;
90 	struct ethhdr *p_ethhdr;
91 	struct mwifiex_sta_node *src_node;
92 	int index;
93 
94 	uap_rx_pd = (struct uap_rxpd *)(skb->data);
95 	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
96 
97 	if ((atomic_read(&adapter->pending_bridged_pkts) >=
98 					     MWIFIEX_BRIDGED_PKTS_THR_HIGH)) {
99 		mwifiex_dbg(priv->adapter, ERROR,
100 			    "Tx: Bridge packet limit reached. Drop packet!\n");
101 		kfree_skb(skb);
102 		mwifiex_uap_cleanup_tx_queues(priv);
103 		return;
104 	}
105 
106 	if (sizeof(*rx_pkt_hdr) +
107 	    le16_to_cpu(uap_rx_pd->rx_pkt_offset) > skb->len) {
108 		mwifiex_dbg(adapter, ERROR,
109 			    "wrong rx packet offset: len=%d,rx_pkt_offset=%d\n",
110 			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset));
111 		priv->stats.rx_dropped++;
112 		dev_kfree_skb_any(skb);
113 		return;
114 	}
115 
116 	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
117 		     sizeof(bridge_tunnel_header))) ||
118 	    (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
119 		     sizeof(rfc1042_header)) &&
120 	     ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_AARP &&
121 	     ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_IPX)) {
122 		/* Replace the 803 header and rfc1042 header (llc/snap) with
123 		 * an Ethernet II header, keep the src/dst and snap_type
124 		 * (ethertype).
125 		 *
126 		 * The firmware only passes up SNAP frames converting all RX
127 		 * data from 802.11 to 802.2/LLC/SNAP frames.
128 		 *
129 		 * To create the Ethernet II, just move the src, dst address
130 		 * right before the snap_type.
131 		 */
132 		p_ethhdr = (struct ethhdr *)
133 			((u8 *)(&rx_pkt_hdr->eth803_hdr)
134 			 + sizeof(rx_pkt_hdr->eth803_hdr)
135 			 + sizeof(rx_pkt_hdr->rfc1042_hdr)
136 			 - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
137 			 - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
138 			 - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));
139 		memcpy(p_ethhdr->h_source, rx_pkt_hdr->eth803_hdr.h_source,
140 		       sizeof(p_ethhdr->h_source));
141 		memcpy(p_ethhdr->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
142 		       sizeof(p_ethhdr->h_dest));
143 		/* Chop off the rxpd + the excess memory from
144 		 * 802.2/llc/snap header that was removed.
145 		 */
146 		hdr_chop = (u8 *)p_ethhdr - (u8 *)uap_rx_pd;
147 	} else {
148 		/* Chop off the rxpd */
149 		hdr_chop = (u8 *)&rx_pkt_hdr->eth803_hdr - (u8 *)uap_rx_pd;
150 	}
151 
152 	/* Chop off the leading header bytes so that it points
153 	 * to the start of either the reconstructed EthII frame
154 	 * or the 802.2/llc/snap frame.
155 	 */
156 	skb_pull(skb, hdr_chop);
157 
158 	if (skb_headroom(skb) < MWIFIEX_MIN_DATA_HEADER_LEN) {
159 		mwifiex_dbg(priv->adapter, ERROR,
160 			    "data: Tx: insufficient skb headroom %d\n",
161 			    skb_headroom(skb));
162 		/* Insufficient skb headroom - allocate a new skb */
163 		new_skb =
164 			skb_realloc_headroom(skb, MWIFIEX_MIN_DATA_HEADER_LEN);
165 		if (unlikely(!new_skb)) {
166 			mwifiex_dbg(priv->adapter, ERROR,
167 				    "Tx: cannot allocate new_skb\n");
168 			kfree_skb(skb);
169 			priv->stats.tx_dropped++;
170 			return;
171 		}
172 
173 		kfree_skb(skb);
174 		skb = new_skb;
175 		mwifiex_dbg(priv->adapter, INFO,
176 			    "info: new skb headroom %d\n",
177 			    skb_headroom(skb));
178 	}
179 
180 	tx_info = MWIFIEX_SKB_TXCB(skb);
181 	memset(tx_info, 0, sizeof(*tx_info));
182 	tx_info->bss_num = priv->bss_num;
183 	tx_info->bss_type = priv->bss_type;
184 	tx_info->flags |= MWIFIEX_BUF_FLAG_BRIDGED_PKT;
185 
186 	src_node = mwifiex_get_sta_entry(priv, rx_pkt_hdr->eth803_hdr.h_source);
187 	if (src_node) {
188 		src_node->stats.last_rx = jiffies;
189 		src_node->stats.rx_bytes += skb->len;
190 		src_node->stats.rx_packets++;
191 		src_node->stats.last_tx_rate = uap_rx_pd->rx_rate;
192 		src_node->stats.last_tx_htinfo = uap_rx_pd->ht_info;
193 	}
194 
195 	if (is_unicast_ether_addr(rx_pkt_hdr->eth803_hdr.h_dest)) {
196 		/* Update bridge packet statistics as the
197 		 * packet is not going to kernel/upper layer.
198 		 */
199 		priv->stats.rx_bytes += skb->len;
200 		priv->stats.rx_packets++;
201 
202 		/* Sending bridge packet to TX queue, so save the packet
203 		 * length in TXCB to update statistics in TX complete.
204 		 */
205 		tx_info->pkt_len = skb->len;
206 	}
207 
208 	__net_timestamp(skb);
209 
210 	index = mwifiex_1d_to_wmm_queue[skb->priority];
211 	atomic_inc(&priv->wmm_tx_pending[index]);
212 	mwifiex_wmm_add_buf_txqueue(priv, skb);
213 	atomic_inc(&adapter->tx_pending);
214 	atomic_inc(&adapter->pending_bridged_pkts);
215 
216 	mwifiex_queue_main_work(priv->adapter);
217 
218 	return;
219 }
220 
221 /*
222  * This function contains logic for AP packet forwarding.
223  *
224  * If a packet is multicast/broadcast, it is sent to kernel/upper layer
225  * as well as queued back to AP TX queue so that it can be sent to other
226  * associated stations.
227  * If a packet is unicast and RA is present in associated station list,
228  * it is again requeued into AP TX queue.
229  * If a packet is unicast and RA is not in associated station list,
230  * packet is forwarded to kernel to handle routing logic.
231  */
232 int mwifiex_handle_uap_rx_forward(struct mwifiex_private *priv,
233 				  struct sk_buff *skb)
234 {
235 	struct mwifiex_adapter *adapter = priv->adapter;
236 	struct uap_rxpd *uap_rx_pd;
237 	struct rx_packet_hdr *rx_pkt_hdr;
238 	u8 ra[ETH_ALEN];
239 	struct sk_buff *skb_uap;
240 
241 	uap_rx_pd = (struct uap_rxpd *)(skb->data);
242 	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
243 
244 	/* don't do packet forwarding in disconnected state */
245 	if (!priv->media_connected) {
246 		mwifiex_dbg(adapter, ERROR,
247 			    "drop packet in disconnected state.\n");
248 		dev_kfree_skb_any(skb);
249 		return 0;
250 	}
251 
252 	memcpy(ra, rx_pkt_hdr->eth803_hdr.h_dest, ETH_ALEN);
253 
254 	if (is_multicast_ether_addr(ra)) {
255 		skb_uap = skb_copy(skb, GFP_ATOMIC);
256 		if (likely(skb_uap)) {
257 			mwifiex_uap_queue_bridged_pkt(priv, skb_uap);
258 		} else {
259 			mwifiex_dbg(adapter, ERROR,
260 				    "failed to copy skb for uAP\n");
261 			priv->stats.rx_dropped++;
262 			dev_kfree_skb_any(skb);
263 			return -1;
264 		}
265 	} else {
266 		if (mwifiex_get_sta_entry(priv, ra)) {
267 			/* Requeue Intra-BSS packet */
268 			mwifiex_uap_queue_bridged_pkt(priv, skb);
269 			return 0;
270 		}
271 	}
272 
273 	/* Forward unicat/Inter-BSS packets to kernel. */
274 	return mwifiex_process_rx_packet(priv, skb);
275 }
276 
277 int mwifiex_uap_recv_packet(struct mwifiex_private *priv,
278 			    struct sk_buff *skb)
279 {
280 	struct mwifiex_adapter *adapter = priv->adapter;
281 	struct mwifiex_sta_node *src_node;
282 	struct ethhdr *p_ethhdr;
283 	struct sk_buff *skb_uap;
284 	struct mwifiex_txinfo *tx_info;
285 
286 	if (!skb)
287 		return -1;
288 
289 	p_ethhdr = (void *)skb->data;
290 	src_node = mwifiex_get_sta_entry(priv, p_ethhdr->h_source);
291 	if (src_node) {
292 		src_node->stats.last_rx = jiffies;
293 		src_node->stats.rx_bytes += skb->len;
294 		src_node->stats.rx_packets++;
295 	}
296 
297 	if (is_multicast_ether_addr(p_ethhdr->h_dest) ||
298 	    mwifiex_get_sta_entry(priv, p_ethhdr->h_dest)) {
299 		if (skb_headroom(skb) < MWIFIEX_MIN_DATA_HEADER_LEN)
300 			skb_uap =
301 			skb_realloc_headroom(skb, MWIFIEX_MIN_DATA_HEADER_LEN);
302 		else
303 			skb_uap = skb_copy(skb, GFP_ATOMIC);
304 
305 		if (likely(skb_uap)) {
306 			tx_info = MWIFIEX_SKB_TXCB(skb_uap);
307 			memset(tx_info, 0, sizeof(*tx_info));
308 			tx_info->bss_num = priv->bss_num;
309 			tx_info->bss_type = priv->bss_type;
310 			tx_info->flags |= MWIFIEX_BUF_FLAG_BRIDGED_PKT;
311 			__net_timestamp(skb_uap);
312 			mwifiex_wmm_add_buf_txqueue(priv, skb_uap);
313 			atomic_inc(&adapter->tx_pending);
314 			atomic_inc(&adapter->pending_bridged_pkts);
315 			if ((atomic_read(&adapter->pending_bridged_pkts) >=
316 					MWIFIEX_BRIDGED_PKTS_THR_HIGH)) {
317 				mwifiex_dbg(adapter, ERROR,
318 					    "Tx: Bridge packet limit reached. Drop packet!\n");
319 				mwifiex_uap_cleanup_tx_queues(priv);
320 			}
321 
322 		} else {
323 			mwifiex_dbg(adapter, ERROR, "failed to allocate skb_uap");
324 		}
325 
326 		mwifiex_queue_main_work(adapter);
327 		/* Don't forward Intra-BSS unicast packet to upper layer*/
328 		if (mwifiex_get_sta_entry(priv, p_ethhdr->h_dest))
329 			return 0;
330 	}
331 
332 	skb->dev = priv->netdev;
333 	skb->protocol = eth_type_trans(skb, priv->netdev);
334 	skb->ip_summed = CHECKSUM_NONE;
335 
336 	/* This is required only in case of 11n and USB/PCIE as we alloc
337 	 * a buffer of 4K only if its 11N (to be able to receive 4K
338 	 * AMSDU packets). In case of SD we allocate buffers based
339 	 * on the size of packet and hence this is not needed.
340 	 *
341 	 * Modifying the truesize here as our allocation for each
342 	 * skb is 4K but we only receive 2K packets and this cause
343 	 * the kernel to start dropping packets in case where
344 	 * application has allocated buffer based on 2K size i.e.
345 	 * if there a 64K packet received (in IP fragments and
346 	 * application allocates 64K to receive this packet but
347 	 * this packet would almost double up because we allocate
348 	 * each 1.5K fragment in 4K and pass it up. As soon as the
349 	 * 64K limit hits kernel will start to drop rest of the
350 	 * fragments. Currently we fail the Filesndl-ht.scr script
351 	 * for UDP, hence this fix
352 	 */
353 	if ((adapter->iface_type == MWIFIEX_USB ||
354 	     adapter->iface_type == MWIFIEX_PCIE) &&
355 	    skb->truesize > MWIFIEX_RX_DATA_BUF_SIZE)
356 		skb->truesize += (skb->len - MWIFIEX_RX_DATA_BUF_SIZE);
357 
358 	/* Forward multicast/broadcast packet to upper layer*/
359 	netif_rx(skb);
360 	return 0;
361 }
362 
363 /*
364  * This function processes the packet received on AP interface.
365  *
366  * The function looks into the RxPD and performs sanity tests on the
367  * received buffer to ensure its a valid packet before processing it
368  * further. If the packet is determined to be aggregated, it is
369  * de-aggregated accordingly. Then skb is passed to AP packet forwarding logic.
370  *
371  * The completion callback is called after processing is complete.
372  */
373 int mwifiex_process_uap_rx_packet(struct mwifiex_private *priv,
374 				  struct sk_buff *skb)
375 {
376 	struct mwifiex_adapter *adapter = priv->adapter;
377 	int ret;
378 	struct uap_rxpd *uap_rx_pd;
379 	struct rx_packet_hdr *rx_pkt_hdr;
380 	u16 rx_pkt_type;
381 	u8 ta[ETH_ALEN], pkt_type;
382 	struct mwifiex_sta_node *node;
383 
384 	uap_rx_pd = (struct uap_rxpd *)(skb->data);
385 	rx_pkt_type = le16_to_cpu(uap_rx_pd->rx_pkt_type);
386 	rx_pkt_hdr = (void *)uap_rx_pd + le16_to_cpu(uap_rx_pd->rx_pkt_offset);
387 
388 	if (le16_to_cpu(uap_rx_pd->rx_pkt_offset) +
389 	    sizeof(rx_pkt_hdr->eth803_hdr) > skb->len) {
390 		mwifiex_dbg(adapter, ERROR,
391 			    "wrong rx packet for struct ethhdr: len=%d, offset=%d\n",
392 			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset));
393 		priv->stats.rx_dropped++;
394 		dev_kfree_skb_any(skb);
395 		return 0;
396 	}
397 
398 	ether_addr_copy(ta, rx_pkt_hdr->eth803_hdr.h_source);
399 
400 	if ((le16_to_cpu(uap_rx_pd->rx_pkt_offset) +
401 	     le16_to_cpu(uap_rx_pd->rx_pkt_length)) > (u16) skb->len) {
402 		mwifiex_dbg(adapter, ERROR,
403 			    "wrong rx packet: len=%d, offset=%d, length=%d\n",
404 			    skb->len, le16_to_cpu(uap_rx_pd->rx_pkt_offset),
405 			    le16_to_cpu(uap_rx_pd->rx_pkt_length));
406 		priv->stats.rx_dropped++;
407 
408 		node = mwifiex_get_sta_entry(priv, ta);
409 		if (node)
410 			node->stats.tx_failed++;
411 
412 		dev_kfree_skb_any(skb);
413 		return 0;
414 	}
415 
416 	if (rx_pkt_type == PKT_TYPE_MGMT) {
417 		ret = mwifiex_process_mgmt_packet(priv, skb);
418 		if (ret)
419 			mwifiex_dbg(adapter, DATA, "Rx of mgmt packet failed");
420 		dev_kfree_skb_any(skb);
421 		return ret;
422 	}
423 
424 
425 	if (rx_pkt_type != PKT_TYPE_BAR && uap_rx_pd->priority < MAX_NUM_TID) {
426 		spin_lock_bh(&priv->sta_list_spinlock);
427 		node = mwifiex_get_sta_entry(priv, ta);
428 		if (node)
429 			node->rx_seq[uap_rx_pd->priority] =
430 						le16_to_cpu(uap_rx_pd->seq_num);
431 		spin_unlock_bh(&priv->sta_list_spinlock);
432 	}
433 
434 	if (!priv->ap_11n_enabled ||
435 	    (!mwifiex_11n_get_rx_reorder_tbl(priv, uap_rx_pd->priority, ta) &&
436 	    (le16_to_cpu(uap_rx_pd->rx_pkt_type) != PKT_TYPE_AMSDU))) {
437 		ret = mwifiex_handle_uap_rx_forward(priv, skb);
438 		return ret;
439 	}
440 
441 	/* Reorder and send to kernel */
442 	pkt_type = (u8)le16_to_cpu(uap_rx_pd->rx_pkt_type);
443 	ret = mwifiex_11n_rx_reorder_pkt(priv, le16_to_cpu(uap_rx_pd->seq_num),
444 					 uap_rx_pd->priority, ta, pkt_type,
445 					 skb);
446 
447 	if (ret || (rx_pkt_type == PKT_TYPE_BAR))
448 		dev_kfree_skb_any(skb);
449 
450 	if (ret)
451 		priv->stats.rx_dropped++;
452 
453 	return ret;
454 }
455 
456 /*
457  * This function fills the TxPD for AP tx packets.
458  *
459  * The Tx buffer received by this function should already have the
460  * header space allocated for TxPD.
461  *
462  * This function inserts the TxPD in between interface header and actual
463  * data and adjusts the buffer pointers accordingly.
464  *
465  * The following TxPD fields are set by this function, as required -
466  *      - BSS number
467  *      - Tx packet length and offset
468  *      - Priority
469  *      - Packet delay
470  *      - Priority specific Tx control
471  *      - Flags
472  */
473 void mwifiex_process_uap_txpd(struct mwifiex_private *priv,
474 			      struct sk_buff *skb)
475 {
476 	struct mwifiex_adapter *adapter = priv->adapter;
477 	struct uap_txpd *txpd;
478 	struct mwifiex_txinfo *tx_info = MWIFIEX_SKB_TXCB(skb);
479 	int pad;
480 	u16 pkt_type, pkt_offset;
481 	int hroom = adapter->intf_hdr_len;
482 
483 	pkt_type = mwifiex_is_skb_mgmt_frame(skb) ? PKT_TYPE_MGMT : 0;
484 
485 	pad = ((uintptr_t)skb->data - (sizeof(*txpd) + hroom)) &
486 	       (MWIFIEX_DMA_ALIGN_SZ - 1);
487 
488 	skb_push(skb, sizeof(*txpd) + pad);
489 
490 	txpd = (struct uap_txpd *)skb->data;
491 	memset(txpd, 0, sizeof(*txpd));
492 	txpd->bss_num = priv->bss_num;
493 	txpd->bss_type = priv->bss_type;
494 	txpd->tx_pkt_length = cpu_to_le16((u16)(skb->len - (sizeof(*txpd) +
495 						pad)));
496 	txpd->priority = (u8)skb->priority;
497 
498 	txpd->pkt_delay_2ms = mwifiex_wmm_compute_drv_pkt_delay(priv, skb);
499 
500 	if (tx_info->flags & MWIFIEX_BUF_FLAG_EAPOL_TX_STATUS ||
501 	    tx_info->flags & MWIFIEX_BUF_FLAG_ACTION_TX_STATUS) {
502 		txpd->tx_token_id = tx_info->ack_frame_id;
503 		txpd->flags |= MWIFIEX_TXPD_FLAGS_REQ_TX_STATUS;
504 	}
505 
506 	if (txpd->priority < ARRAY_SIZE(priv->wmm.user_pri_pkt_tx_ctrl))
507 		/*
508 		 * Set the priority specific tx_control field, setting of 0 will
509 		 * cause the default value to be used later in this function.
510 		 */
511 		txpd->tx_control =
512 		    cpu_to_le32(priv->wmm.user_pri_pkt_tx_ctrl[txpd->priority]);
513 
514 	/* Offset of actual data */
515 	pkt_offset = sizeof(*txpd) + pad;
516 	if (pkt_type == PKT_TYPE_MGMT) {
517 		/* Set the packet type and add header for management frame */
518 		txpd->tx_pkt_type = cpu_to_le16(pkt_type);
519 		pkt_offset += MWIFIEX_MGMT_FRAME_HEADER_SIZE;
520 	}
521 
522 	txpd->tx_pkt_offset = cpu_to_le16(pkt_offset);
523 
524 	/* make space for adapter->intf_hdr_len */
525 	skb_push(skb, hroom);
526 
527 	if (!txpd->tx_control)
528 		/* TxCtrl set by user or default */
529 		txpd->tx_control = cpu_to_le32(priv->pkt_tx_ctrl);
530 }
531