1/*
2 * Marvell Wireless LAN device driver: station RX data handling
3 *
4 * Copyright (C) 2011-2014, 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 <uapi/linux/ipv6.h>
21#include <net/ndisc.h>
22#include "decl.h"
23#include "ioctl.h"
24#include "util.h"
25#include "fw.h"
26#include "main.h"
27#include "11n_aggr.h"
28#include "11n_rxreorder.h"
29
30/* This function checks if a frame is IPv4 ARP or IPv6 Neighbour advertisement
31 * frame. If frame has both source and destination mac address as same, this
32 * function drops such gratuitous frames.
33 */
34static bool
35mwifiex_discard_gratuitous_arp(struct mwifiex_private *priv,
36			       struct sk_buff *skb)
37{
38	const struct mwifiex_arp_eth_header *arp;
39	struct ethhdr *eth;
40	struct ipv6hdr *ipv6;
41	struct icmp6hdr *icmpv6;
42
43	eth = (struct ethhdr *)skb->data;
44	switch (ntohs(eth->h_proto)) {
45	case ETH_P_ARP:
46		arp = (void *)(skb->data + sizeof(struct ethhdr));
47		if (arp->hdr.ar_op == htons(ARPOP_REPLY) ||
48		    arp->hdr.ar_op == htons(ARPOP_REQUEST)) {
49			if (!memcmp(arp->ar_sip, arp->ar_tip, 4))
50				return true;
51		}
52		break;
53	case ETH_P_IPV6:
54		ipv6 = (void *)(skb->data + sizeof(struct ethhdr));
55		icmpv6 = (void *)(skb->data + sizeof(struct ethhdr) +
56				  sizeof(struct ipv6hdr));
57		if (NDISC_NEIGHBOUR_ADVERTISEMENT == icmpv6->icmp6_type) {
58			if (!memcmp(&ipv6->saddr, &ipv6->daddr,
59				    sizeof(struct in6_addr)))
60				return true;
61		}
62		break;
63	default:
64		break;
65	}
66
67	return false;
68}
69
70/*
71 * This function processes the received packet and forwards it
72 * to kernel/upper layer.
73 *
74 * This function parses through the received packet and determines
75 * if it is a debug packet or normal packet.
76 *
77 * For non-debug packets, the function chops off unnecessary leading
78 * header bytes, reconstructs the packet as an ethernet frame or
79 * 802.2/llc/snap frame as required, and sends it to kernel/upper layer.
80 *
81 * The completion callback is called after processing in complete.
82 */
83int mwifiex_process_rx_packet(struct mwifiex_private *priv,
84			      struct sk_buff *skb)
85{
86	int ret;
87	struct rx_packet_hdr *rx_pkt_hdr;
88	struct rxpd *local_rx_pd;
89	int hdr_chop;
90	struct ethhdr *eth;
91	u16 rx_pkt_off, rx_pkt_len;
92	u8 *offset;
93	u8 adj_rx_rate = 0;
94
95	local_rx_pd = (struct rxpd *) (skb->data);
96
97	rx_pkt_off = le16_to_cpu(local_rx_pd->rx_pkt_offset);
98	rx_pkt_len = le16_to_cpu(local_rx_pd->rx_pkt_length);
99	rx_pkt_hdr = (void *)local_rx_pd + rx_pkt_off;
100
101	if ((!memcmp(&rx_pkt_hdr->rfc1042_hdr, bridge_tunnel_header,
102		     sizeof(bridge_tunnel_header))) ||
103	    (!memcmp(&rx_pkt_hdr->rfc1042_hdr, rfc1042_header,
104		     sizeof(rfc1042_header)) &&
105	     ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_AARP &&
106	     ntohs(rx_pkt_hdr->rfc1042_hdr.snap_type) != ETH_P_IPX)) {
107		/*
108		 *  Replace the 803 header and rfc1042 header (llc/snap) with an
109		 *    EthernetII header, keep the src/dst and snap_type
110		 *    (ethertype).
111		 *  The firmware only passes up SNAP frames converting
112		 *    all RX Data from 802.11 to 802.2/LLC/SNAP frames.
113		 *  To create the Ethernet II, just move the src, dst address
114		 *    right before the snap_type.
115		 */
116		eth = (struct ethhdr *)
117			((u8 *) &rx_pkt_hdr->eth803_hdr
118			 + sizeof(rx_pkt_hdr->eth803_hdr) +
119			 sizeof(rx_pkt_hdr->rfc1042_hdr)
120			 - sizeof(rx_pkt_hdr->eth803_hdr.h_dest)
121			 - sizeof(rx_pkt_hdr->eth803_hdr.h_source)
122			 - sizeof(rx_pkt_hdr->rfc1042_hdr.snap_type));
123
124		memcpy(eth->h_source, rx_pkt_hdr->eth803_hdr.h_source,
125		       sizeof(eth->h_source));
126		memcpy(eth->h_dest, rx_pkt_hdr->eth803_hdr.h_dest,
127		       sizeof(eth->h_dest));
128
129		/* Chop off the rxpd + the excess memory from the 802.2/llc/snap
130		   header that was removed. */
131		hdr_chop = (u8 *) eth - (u8 *) local_rx_pd;
132	} else {
133		/* Chop off the rxpd */
134		hdr_chop = (u8 *) &rx_pkt_hdr->eth803_hdr -
135			(u8 *) local_rx_pd;
136	}
137
138	/* Chop off the leading header bytes so the it points to the start of
139	   either the reconstructed EthII frame or the 802.2/llc/snap frame */
140	skb_pull(skb, hdr_chop);
141
142	if (priv->hs2_enabled &&
143	    mwifiex_discard_gratuitous_arp(priv, skb)) {
144		mwifiex_dbg(priv->adapter, INFO, "Bypassed Gratuitous ARP\n");
145		dev_kfree_skb_any(skb);
146		return 0;
147	}
148
149	if (ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info) &&
150	    ntohs(rx_pkt_hdr->eth803_hdr.h_proto) == ETH_P_TDLS) {
151		offset = (u8 *)local_rx_pd + rx_pkt_off;
152		mwifiex_process_tdls_action_frame(priv, offset, rx_pkt_len);
153	}
154
155	priv->rxpd_rate = local_rx_pd->rx_rate;
156
157	priv->rxpd_htinfo = local_rx_pd->ht_info;
158
159	if (GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_STA ||
160	    GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_UAP) {
161		adj_rx_rate = mwifiex_adjust_data_rate(priv, priv->rxpd_rate,
162						       priv->rxpd_htinfo);
163		mwifiex_hist_data_add(priv, adj_rx_rate, local_rx_pd->snr,
164				      local_rx_pd->nf);
165	}
166
167	ret = mwifiex_recv_packet(priv, skb);
168	if (ret == -1)
169		mwifiex_dbg(priv->adapter, ERROR,
170			    "recv packet failed\n");
171
172	return ret;
173}
174
175/*
176 * This function processes the received buffer.
177 *
178 * The function looks into the RxPD and performs sanity tests on the
179 * received buffer to ensure its a valid packet, before processing it
180 * further. If the packet is determined to be aggregated, it is
181 * de-aggregated accordingly. Non-unicast packets are sent directly to
182 * the kernel/upper layers. Unicast packets are handed over to the
183 * Rx reordering routine if 11n is enabled.
184 *
185 * The completion callback is called after processing in complete.
186 */
187int mwifiex_process_sta_rx_packet(struct mwifiex_private *priv,
188				  struct sk_buff *skb)
189{
190	struct mwifiex_adapter *adapter = priv->adapter;
191	int ret = 0;
192	struct rxpd *local_rx_pd;
193	struct rx_packet_hdr *rx_pkt_hdr;
194	u8 ta[ETH_ALEN];
195	u16 rx_pkt_type, rx_pkt_offset, rx_pkt_length, seq_num;
196	struct mwifiex_sta_node *sta_ptr;
197
198	local_rx_pd = (struct rxpd *) (skb->data);
199	rx_pkt_type = le16_to_cpu(local_rx_pd->rx_pkt_type);
200	rx_pkt_offset = le16_to_cpu(local_rx_pd->rx_pkt_offset);
201	rx_pkt_length = le16_to_cpu(local_rx_pd->rx_pkt_length);
202	seq_num = le16_to_cpu(local_rx_pd->seq_num);
203
204	rx_pkt_hdr = (void *)local_rx_pd + rx_pkt_offset;
205
206	if ((rx_pkt_offset + rx_pkt_length) > (u16) skb->len) {
207		mwifiex_dbg(adapter, ERROR,
208			    "wrong rx packet: len=%d, rx_pkt_offset=%d, rx_pkt_length=%d\n",
209			    skb->len, rx_pkt_offset, rx_pkt_length);
210		priv->stats.rx_dropped++;
211		dev_kfree_skb_any(skb);
212		return ret;
213	}
214
215	if (rx_pkt_type == PKT_TYPE_MGMT) {
216		ret = mwifiex_process_mgmt_packet(priv, skb);
217		if (ret)
218			mwifiex_dbg(adapter, ERROR, "Rx of mgmt packet failed");
219		dev_kfree_skb_any(skb);
220		return ret;
221	}
222
223	/*
224	 * If the packet is not an unicast packet then send the packet
225	 * directly to os. Don't pass thru rx reordering
226	 */
227	if ((!IS_11N_ENABLED(priv) &&
228	     !(ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info) &&
229	       !(local_rx_pd->flags & MWIFIEX_RXPD_FLAGS_TDLS_PACKET))) ||
230	    !ether_addr_equal_unaligned(priv->curr_addr, rx_pkt_hdr->eth803_hdr.h_dest)) {
231		mwifiex_process_rx_packet(priv, skb);
232		return ret;
233	}
234
235	if (mwifiex_queuing_ra_based(priv) ||
236	    (ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info) &&
237	     local_rx_pd->flags & MWIFIEX_RXPD_FLAGS_TDLS_PACKET)) {
238		memcpy(ta, rx_pkt_hdr->eth803_hdr.h_source, ETH_ALEN);
239		if (local_rx_pd->flags & MWIFIEX_RXPD_FLAGS_TDLS_PACKET &&
240		    local_rx_pd->priority < MAX_NUM_TID) {
241			sta_ptr = mwifiex_get_sta_entry(priv, ta);
242			if (sta_ptr)
243				sta_ptr->rx_seq[local_rx_pd->priority] =
244					      le16_to_cpu(local_rx_pd->seq_num);
245			mwifiex_auto_tdls_update_peer_signal(priv, ta,
246							     local_rx_pd->snr,
247							     local_rx_pd->nf);
248		}
249	} else {
250		if (rx_pkt_type != PKT_TYPE_BAR)
251			priv->rx_seq[local_rx_pd->priority] = seq_num;
252		memcpy(ta, priv->curr_bss_params.bss_descriptor.mac_address,
253		       ETH_ALEN);
254	}
255
256	/* Reorder and send to OS */
257	ret = mwifiex_11n_rx_reorder_pkt(priv, seq_num, local_rx_pd->priority,
258					 ta, (u8) rx_pkt_type, skb);
259
260	if (ret || (rx_pkt_type == PKT_TYPE_BAR))
261		dev_kfree_skb_any(skb);
262
263	if (ret)
264		priv->stats.rx_dropped++;
265
266	return ret;
267}
268