1 /*
2  * Marvell Wireless LAN device driver: station RX data handling
3  *
4  * Copyright (C) 2011, Marvell International Ltd.
5  *
6  * This software file (the "File") is distributed by Marvell International
7  * Ltd. under the terms of the GNU General Public License Version 2, June 1991
8  * (the "License").  You may use, redistribute and/or modify this File in
9  * accordance with the terms and conditions of the License, a copy of which
10  * is available by writing to the Free Software Foundation, Inc.,
11  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
12  * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
13  *
14  * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
16  * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
17  * this warranty disclaimer.
18  */
19 
20 #include "decl.h"
21 #include "ioctl.h"
22 #include "util.h"
23 #include "fw.h"
24 #include "main.h"
25 #include "11n_aggr.h"
26 #include "11n_rxreorder.h"
27 
28 /*
29  * This function processes the received packet and forwards it
30  * to kernel/upper layer.
31  *
32  * This function parses through the received packet and determines
33  * if it is a debug packet or normal packet.
34  *
35  * For non-debug packets, the function chops off unnecessary leading
36  * header bytes, reconstructs the packet as an ethernet frame or
37  * 802.2/llc/snap frame as required, and sends it to kernel/upper layer.
38  *
39  * The completion callback is called after processing in complete.
40  */
mwifiex_process_rx_packet(struct mwifiex_adapter * adapter,struct sk_buff * skb)41 int mwifiex_process_rx_packet(struct mwifiex_adapter *adapter,
42 			      struct sk_buff *skb)
43 {
44 	int ret;
45 	struct mwifiex_rxinfo *rx_info = MWIFIEX_SKB_RXCB(skb);
46 	struct mwifiex_private *priv = adapter->priv[rx_info->bss_index];
47 	struct rx_packet_hdr *rx_pkt_hdr;
48 	struct rxpd *local_rx_pd;
49 	int hdr_chop;
50 	struct ethhdr *eth_hdr;
51 	u8 rfc1042_eth_hdr[ETH_ALEN] = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00 };
52 
53 	local_rx_pd = (struct rxpd *) (skb->data);
54 
55 	rx_pkt_hdr = (struct rx_packet_hdr *) ((u8 *) local_rx_pd +
56 				local_rx_pd->rx_pkt_offset);
57 
58 	if (!memcmp(&rx_pkt_hdr->rfc1042_hdr,
59 		    rfc1042_eth_hdr, sizeof(rfc1042_eth_hdr))) {
60 		/*
61 		 *  Replace the 803 header and rfc1042 header (llc/snap) with an
62 		 *    EthernetII header, keep the src/dst and snap_type
63 		 *    (ethertype).
64 		 *  The firmware only passes up SNAP frames converting
65 		 *    all RX Data from 802.11 to 802.2/LLC/SNAP frames.
66 		 *  To create the Ethernet II, just move the src, dst address
67 		 *    right before the snap_type.
68 		 */
69 		eth_hdr = (struct ethhdr *)
70 			((u8 *) &rx_pkt_hdr->eth803_hdr
71 			 + sizeof(rx_pkt_hdr->eth803_hdr) +
72 			 sizeof(rx_pkt_hdr->rfc1042_hdr)
73 			 - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
74 			 - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
75 			 - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));
76 
77 		memcpy(eth_hdr->h_source, rx_pkt_hdr->eth803_hdr.h_source,
78 		       sizeof(eth_hdr->h_source));
79 		memcpy(eth_hdr->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
80 		       sizeof(eth_hdr->h_dest));
81 
82 		/* Chop off the rxpd + the excess memory from the 802.2/llc/snap
83 		   header that was removed. */
84 		hdr_chop = (u8 *) eth_hdr - (u8 *) local_rx_pd;
85 	} else {
86 		/* Chop off the rxpd */
87 		hdr_chop = (u8 *) &rx_pkt_hdr->eth803_hdr -
88 			(u8 *) local_rx_pd;
89 	}
90 
91 	/* Chop off the leading header bytes so the it points to the start of
92 	   either the reconstructed EthII frame or the 802.2/llc/snap frame */
93 	skb_pull(skb, hdr_chop);
94 
95 	priv->rxpd_rate = local_rx_pd->rx_rate;
96 
97 	priv->rxpd_htinfo = local_rx_pd->ht_info;
98 
99 	ret = mwifiex_recv_packet(adapter, skb);
100 	if (ret == -1)
101 		dev_err(adapter->dev, "recv packet failed\n");
102 
103 	return ret;
104 }
105 
106 /*
107  * This function processes the received buffer.
108  *
109  * The function looks into the RxPD and performs sanity tests on the
110  * received buffer to ensure its a valid packet, before processing it
111  * further. If the packet is determined to be aggregated, it is
112  * de-aggregated accordingly. Non-unicast packets are sent directly to
113  * the kernel/upper layers. Unicast packets are handed over to the
114  * Rx reordering routine if 11n is enabled.
115  *
116  * The completion callback is called after processing in complete.
117  */
mwifiex_process_sta_rx_packet(struct mwifiex_adapter * adapter,struct sk_buff * skb)118 int mwifiex_process_sta_rx_packet(struct mwifiex_adapter *adapter,
119 				  struct sk_buff *skb)
120 {
121 	int ret = 0;
122 	struct rxpd *local_rx_pd;
123 	struct mwifiex_rxinfo *rx_info = MWIFIEX_SKB_RXCB(skb);
124 	struct rx_packet_hdr *rx_pkt_hdr;
125 	u8 ta[ETH_ALEN];
126 	u16 rx_pkt_type;
127 	struct mwifiex_private *priv = adapter->priv[rx_info->bss_index];
128 
129 	if (!priv)
130 		return -1;
131 
132 	local_rx_pd = (struct rxpd *) (skb->data);
133 	rx_pkt_type = local_rx_pd->rx_pkt_type;
134 
135 	rx_pkt_hdr = (struct rx_packet_hdr *) ((u8 *) local_rx_pd +
136 					local_rx_pd->rx_pkt_offset);
137 
138 	if ((local_rx_pd->rx_pkt_offset + local_rx_pd->rx_pkt_length) >
139 	    (u16) skb->len) {
140 		dev_err(adapter->dev, "wrong rx packet: len=%d,"
141 			" rx_pkt_offset=%d, rx_pkt_length=%d\n", skb->len,
142 		       local_rx_pd->rx_pkt_offset, local_rx_pd->rx_pkt_length);
143 		priv->stats.rx_dropped++;
144 		dev_kfree_skb_any(skb);
145 		return ret;
146 	}
147 
148 	if (local_rx_pd->rx_pkt_type == PKT_TYPE_AMSDU) {
149 		struct sk_buff_head list;
150 		struct sk_buff *rx_skb;
151 
152 		__skb_queue_head_init(&list);
153 
154 		skb_pull(skb, local_rx_pd->rx_pkt_offset);
155 		skb_trim(skb, local_rx_pd->rx_pkt_length);
156 
157 		ieee80211_amsdu_to_8023s(skb, &list, priv->curr_addr,
158 				priv->wdev->iftype, 0, false);
159 
160 		while (!skb_queue_empty(&list)) {
161 			rx_skb = __skb_dequeue(&list);
162 			ret = mwifiex_recv_packet(adapter, rx_skb);
163 			if (ret == -1)
164 				dev_err(adapter->dev, "Rx of A-MSDU failed");
165 		}
166 		return 0;
167 	}
168 
169 	/*
170 	 * If the packet is not an unicast packet then send the packet
171 	 * directly to os. Don't pass thru rx reordering
172 	 */
173 	if (!IS_11N_ENABLED(priv) ||
174 	    memcmp(priv->curr_addr, rx_pkt_hdr->eth803_hdr.h_dest, ETH_ALEN)) {
175 		mwifiex_process_rx_packet(adapter, skb);
176 		return ret;
177 	}
178 
179 	if (mwifiex_queuing_ra_based(priv)) {
180 		memcpy(ta, rx_pkt_hdr->eth803_hdr.h_source, ETH_ALEN);
181 	} else {
182 		if (rx_pkt_type != PKT_TYPE_BAR)
183 			priv->rx_seq[local_rx_pd->priority] =
184 						local_rx_pd->seq_num;
185 		memcpy(ta, priv->curr_bss_params.bss_descriptor.mac_address,
186 		       ETH_ALEN);
187 	}
188 
189 	/* Reorder and send to OS */
190 	ret = mwifiex_11n_rx_reorder_pkt(priv, local_rx_pd->seq_num,
191 					     local_rx_pd->priority, ta,
192 					     (u8) local_rx_pd->rx_pkt_type,
193 					     skb);
194 
195 	if (ret || (rx_pkt_type == PKT_TYPE_BAR))
196 		dev_kfree_skb_any(skb);
197 
198 	if (ret)
199 		priv->stats.rx_dropped++;
200 
201 	return ret;
202 }
203