1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * This file contains the handling of RX in wlan driver.
4 */
5
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8 #include <linux/etherdevice.h>
9 #include <linux/hardirq.h>
10 #include <linux/slab.h>
11 #include <linux/types.h>
12 #include <linux/export.h>
13 #include <net/cfg80211.h>
14
15 #include "defs.h"
16 #include "host.h"
17 #include "radiotap.h"
18 #include "decl.h"
19 #include "dev.h"
20 #include "mesh.h"
21
22 struct eth803hdr {
23 u8 dest_addr[6];
24 u8 src_addr[6];
25 u16 h803_len;
26 } __packed;
27
28 struct rfc1042hdr {
29 u8 llc_dsap;
30 u8 llc_ssap;
31 u8 llc_ctrl;
32 u8 snap_oui[3];
33 u16 snap_type;
34 } __packed;
35
36 struct rxpackethdr {
37 struct eth803hdr eth803_hdr;
38 struct rfc1042hdr rfc1042_hdr;
39 } __packed;
40
41 struct rx80211packethdr {
42 struct rxpd rx_pd;
43 void *eth80211_hdr;
44 } __packed;
45
46 static int process_rxed_802_11_packet(struct lbs_private *priv,
47 struct sk_buff *skb);
48
49 /**
50 * lbs_process_rxed_packet - processes received packet and forwards it
51 * to kernel/upper layer
52 *
53 * @priv: A pointer to &struct lbs_private
54 * @skb: A pointer to skb which includes the received packet
55 * returns: 0 or -1
56 */
lbs_process_rxed_packet(struct lbs_private * priv,struct sk_buff * skb)57 int lbs_process_rxed_packet(struct lbs_private *priv, struct sk_buff *skb)
58 {
59 int ret = 0;
60 struct net_device *dev = priv->dev;
61 struct rxpackethdr *p_rx_pkt;
62 struct rxpd *p_rx_pd;
63 int hdrchop;
64 struct ethhdr *p_ethhdr;
65 static const u8 rfc1042_eth_hdr[] = {
66 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00
67 };
68
69 BUG_ON(!skb);
70
71 skb->ip_summed = CHECKSUM_NONE;
72
73 if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
74 ret = process_rxed_802_11_packet(priv, skb);
75 goto done;
76 }
77
78 p_rx_pd = (struct rxpd *) skb->data;
79 p_rx_pkt = (struct rxpackethdr *) ((u8 *)p_rx_pd +
80 le32_to_cpu(p_rx_pd->pkt_ptr));
81
82 dev = lbs_mesh_set_dev(priv, dev, p_rx_pd);
83
84 lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data,
85 min_t(unsigned int, skb->len, 100));
86
87 if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
88 lbs_deb_rx("rx err: frame received with bad length\n");
89 dev->stats.rx_length_errors++;
90 ret = -EINVAL;
91 dev_kfree_skb(skb);
92 goto done;
93 }
94
95 lbs_deb_rx("rx data: skb->len - pkt_ptr = %d-%zd = %zd\n",
96 skb->len, (size_t)le32_to_cpu(p_rx_pd->pkt_ptr),
97 skb->len - (size_t)le32_to_cpu(p_rx_pd->pkt_ptr));
98
99 lbs_deb_hex(LBS_DEB_RX, "RX Data: Dest", p_rx_pkt->eth803_hdr.dest_addr,
100 sizeof(p_rx_pkt->eth803_hdr.dest_addr));
101 lbs_deb_hex(LBS_DEB_RX, "RX Data: Src", p_rx_pkt->eth803_hdr.src_addr,
102 sizeof(p_rx_pkt->eth803_hdr.src_addr));
103
104 if (memcmp(&p_rx_pkt->rfc1042_hdr,
105 rfc1042_eth_hdr, sizeof(rfc1042_eth_hdr)) == 0) {
106 /*
107 * Replace the 803 header and rfc1042 header (llc/snap) with an
108 * EthernetII header, keep the src/dst and snap_type (ethertype)
109 *
110 * The firmware only passes up SNAP frames converting
111 * all RX Data from 802.11 to 802.2/LLC/SNAP frames.
112 *
113 * To create the Ethernet II, just move the src, dst address right
114 * before the snap_type.
115 */
116 p_ethhdr = (struct ethhdr *)
117 ((u8 *) &p_rx_pkt->eth803_hdr
118 + sizeof(p_rx_pkt->eth803_hdr) + sizeof(p_rx_pkt->rfc1042_hdr)
119 - sizeof(p_rx_pkt->eth803_hdr.dest_addr)
120 - sizeof(p_rx_pkt->eth803_hdr.src_addr)
121 - sizeof(p_rx_pkt->rfc1042_hdr.snap_type));
122
123 memcpy(p_ethhdr->h_source, p_rx_pkt->eth803_hdr.src_addr,
124 sizeof(p_ethhdr->h_source));
125 memcpy(p_ethhdr->h_dest, p_rx_pkt->eth803_hdr.dest_addr,
126 sizeof(p_ethhdr->h_dest));
127
128 /* Chop off the rxpd + the excess memory from the 802.2/llc/snap header
129 * that was removed
130 */
131 hdrchop = (u8 *)p_ethhdr - (u8 *)p_rx_pd;
132 } else {
133 lbs_deb_hex(LBS_DEB_RX, "RX Data: LLC/SNAP",
134 (u8 *) &p_rx_pkt->rfc1042_hdr,
135 sizeof(p_rx_pkt->rfc1042_hdr));
136
137 /* Chop off the rxpd */
138 hdrchop = (u8 *)&p_rx_pkt->eth803_hdr - (u8 *)p_rx_pd;
139 }
140
141 /* Chop off the leading header bytes so the skb points to the start of
142 * either the reconstructed EthII frame or the 802.2/llc/snap frame
143 */
144 skb_pull(skb, hdrchop);
145
146 priv->cur_rate = lbs_fw_index_to_data_rate(p_rx_pd->rx_rate);
147
148 lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
149 dev->stats.rx_bytes += skb->len;
150 dev->stats.rx_packets++;
151
152 skb->protocol = eth_type_trans(skb, dev);
153 if (in_interrupt())
154 netif_rx(skb);
155 else
156 netif_rx_ni(skb);
157
158 ret = 0;
159 done:
160 return ret;
161 }
162 EXPORT_SYMBOL_GPL(lbs_process_rxed_packet);
163
164 /**
165 * convert_mv_rate_to_radiotap - converts Tx/Rx rates from Marvell WLAN format
166 * (see Table 2 in Section 3.1) to IEEE80211_RADIOTAP_RATE units (500 Kb/s)
167 *
168 * @rate: Input rate
169 * returns: Output Rate (0 if invalid)
170 */
convert_mv_rate_to_radiotap(u8 rate)171 static u8 convert_mv_rate_to_radiotap(u8 rate)
172 {
173 switch (rate) {
174 case 0: /* 1 Mbps */
175 return 2;
176 case 1: /* 2 Mbps */
177 return 4;
178 case 2: /* 5.5 Mbps */
179 return 11;
180 case 3: /* 11 Mbps */
181 return 22;
182 /* case 4: reserved */
183 case 5: /* 6 Mbps */
184 return 12;
185 case 6: /* 9 Mbps */
186 return 18;
187 case 7: /* 12 Mbps */
188 return 24;
189 case 8: /* 18 Mbps */
190 return 36;
191 case 9: /* 24 Mbps */
192 return 48;
193 case 10: /* 36 Mbps */
194 return 72;
195 case 11: /* 48 Mbps */
196 return 96;
197 case 12: /* 54 Mbps */
198 return 108;
199 }
200 pr_alert("Invalid Marvell WLAN rate %i\n", rate);
201 return 0;
202 }
203
204 /**
205 * process_rxed_802_11_packet - processes a received 802.11 packet and forwards
206 * it to kernel/upper layer
207 *
208 * @priv: A pointer to &struct lbs_private
209 * @skb: A pointer to skb which includes the received packet
210 * returns: 0 or -1
211 */
process_rxed_802_11_packet(struct lbs_private * priv,struct sk_buff * skb)212 static int process_rxed_802_11_packet(struct lbs_private *priv,
213 struct sk_buff *skb)
214 {
215 int ret = 0;
216 struct net_device *dev = priv->dev;
217 struct rx80211packethdr *p_rx_pkt;
218 struct rxpd *prxpd;
219 struct rx_radiotap_hdr radiotap_hdr;
220 struct rx_radiotap_hdr *pradiotap_hdr;
221
222 p_rx_pkt = (struct rx80211packethdr *) skb->data;
223 prxpd = &p_rx_pkt->rx_pd;
224
225 /* lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data, min(skb->len, 100)); */
226
227 if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
228 lbs_deb_rx("rx err: frame received with bad length\n");
229 dev->stats.rx_length_errors++;
230 ret = -EINVAL;
231 kfree_skb(skb);
232 goto done;
233 }
234
235 lbs_deb_rx("rx data: skb->len-sizeof(RxPd) = %d-%zd = %zd\n",
236 skb->len, sizeof(struct rxpd), skb->len - sizeof(struct rxpd));
237
238 /* create the exported radio header */
239
240 /* radiotap header */
241 memset(&radiotap_hdr, 0, sizeof(radiotap_hdr));
242 /* XXX must check radiotap_hdr.hdr.it_pad for pad */
243 radiotap_hdr.hdr.it_len = cpu_to_le16 (sizeof(struct rx_radiotap_hdr));
244 radiotap_hdr.hdr.it_present = cpu_to_le32 (RX_RADIOTAP_PRESENT);
245 radiotap_hdr.rate = convert_mv_rate_to_radiotap(prxpd->rx_rate);
246 /* XXX must check no carryout */
247 radiotap_hdr.antsignal = prxpd->snr + prxpd->nf;
248
249 /* chop the rxpd */
250 skb_pull(skb, sizeof(struct rxpd));
251
252 /* add space for the new radio header */
253 if ((skb_headroom(skb) < sizeof(struct rx_radiotap_hdr)) &&
254 pskb_expand_head(skb, sizeof(struct rx_radiotap_hdr), 0, GFP_ATOMIC)) {
255 netdev_alert(dev, "%s: couldn't pskb_expand_head\n", __func__);
256 ret = -ENOMEM;
257 kfree_skb(skb);
258 goto done;
259 }
260
261 pradiotap_hdr = skb_push(skb, sizeof(struct rx_radiotap_hdr));
262 memcpy(pradiotap_hdr, &radiotap_hdr, sizeof(struct rx_radiotap_hdr));
263
264 priv->cur_rate = lbs_fw_index_to_data_rate(prxpd->rx_rate);
265
266 lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
267 dev->stats.rx_bytes += skb->len;
268 dev->stats.rx_packets++;
269
270 skb->protocol = eth_type_trans(skb, priv->dev);
271
272 if (in_interrupt())
273 netif_rx(skb);
274 else
275 netif_rx_ni(skb);
276
277 ret = 0;
278
279 done:
280 return ret;
281 }
282
