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
66 BUG_ON(!skb);
67
68 skb->ip_summed = CHECKSUM_NONE;
69
70 if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR) {
71 ret = process_rxed_802_11_packet(priv, skb);
72 goto done;
73 }
74
75 p_rx_pd = (struct rxpd *) skb->data;
76 p_rx_pkt = (struct rxpackethdr *) ((u8 *)p_rx_pd +
77 le32_to_cpu(p_rx_pd->pkt_ptr));
78
79 dev = lbs_mesh_set_dev(priv, dev, p_rx_pd);
80
81 lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data,
82 min_t(unsigned int, skb->len, 100));
83
84 if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
85 lbs_deb_rx("rx err: frame received with bad length\n");
86 dev->stats.rx_length_errors++;
87 ret = -EINVAL;
88 dev_kfree_skb(skb);
89 goto done;
90 }
91
92 lbs_deb_rx("rx data: skb->len - pkt_ptr = %d-%zd = %zd\n",
93 skb->len, (size_t)le32_to_cpu(p_rx_pd->pkt_ptr),
94 skb->len - (size_t)le32_to_cpu(p_rx_pd->pkt_ptr));
95
96 lbs_deb_hex(LBS_DEB_RX, "RX Data: Dest", p_rx_pkt->eth803_hdr.dest_addr,
97 sizeof(p_rx_pkt->eth803_hdr.dest_addr));
98 lbs_deb_hex(LBS_DEB_RX, "RX Data: Src", p_rx_pkt->eth803_hdr.src_addr,
99 sizeof(p_rx_pkt->eth803_hdr.src_addr));
100
101 if (memcmp(&p_rx_pkt->rfc1042_hdr,
102 rfc1042_header, sizeof(rfc1042_header)) == 0) {
103 /*
104 * Replace the 803 header and rfc1042 header (llc/snap) with an
105 * EthernetII header, keep the src/dst and snap_type (ethertype)
106 *
107 * The firmware only passes up SNAP frames converting
108 * all RX Data from 802.11 to 802.2/LLC/SNAP frames.
109 *
110 * To create the Ethernet II, just move the src, dst address right
111 * before the snap_type.
112 */
113 p_ethhdr = (struct ethhdr *)
114 ((u8 *) &p_rx_pkt->eth803_hdr
115 + sizeof(p_rx_pkt->eth803_hdr) + sizeof(p_rx_pkt->rfc1042_hdr)
116 - sizeof(p_rx_pkt->eth803_hdr.dest_addr)
117 - sizeof(p_rx_pkt->eth803_hdr.src_addr)
118 - sizeof(p_rx_pkt->rfc1042_hdr.snap_type));
119
120 memcpy(p_ethhdr->h_source, p_rx_pkt->eth803_hdr.src_addr,
121 sizeof(p_ethhdr->h_source));
122 memcpy(p_ethhdr->h_dest, p_rx_pkt->eth803_hdr.dest_addr,
123 sizeof(p_ethhdr->h_dest));
124
125 /* Chop off the rxpd + the excess memory from the 802.2/llc/snap header
126 * that was removed
127 */
128 hdrchop = (u8 *)p_ethhdr - (u8 *)p_rx_pd;
129 } else {
130 lbs_deb_hex(LBS_DEB_RX, "RX Data: LLC/SNAP",
131 (u8 *) &p_rx_pkt->rfc1042_hdr,
132 sizeof(p_rx_pkt->rfc1042_hdr));
133
134 /* Chop off the rxpd */
135 hdrchop = (u8 *)&p_rx_pkt->eth803_hdr - (u8 *)p_rx_pd;
136 }
137
138 /* Chop off the leading header bytes so the skb points to the start of
139 * either the reconstructed EthII frame or the 802.2/llc/snap frame
140 */
141 skb_pull(skb, hdrchop);
142
143 priv->cur_rate = lbs_fw_index_to_data_rate(p_rx_pd->rx_rate);
144
145 lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
146 dev->stats.rx_bytes += skb->len;
147 dev->stats.rx_packets++;
148
149 skb->protocol = eth_type_trans(skb, dev);
150 netif_rx(skb);
151
152 ret = 0;
153 done:
154 return ret;
155 }
156 EXPORT_SYMBOL_GPL(lbs_process_rxed_packet);
157
158 /**
159 * convert_mv_rate_to_radiotap - converts Tx/Rx rates from Marvell WLAN format
160 * (see Table 2 in Section 3.1) to IEEE80211_RADIOTAP_RATE units (500 Kb/s)
161 *
162 * @rate: Input rate
163 * returns: Output Rate (0 if invalid)
164 */
convert_mv_rate_to_radiotap(u8 rate)165 static u8 convert_mv_rate_to_radiotap(u8 rate)
166 {
167 switch (rate) {
168 case 0: /* 1 Mbps */
169 return 2;
170 case 1: /* 2 Mbps */
171 return 4;
172 case 2: /* 5.5 Mbps */
173 return 11;
174 case 3: /* 11 Mbps */
175 return 22;
176 /* case 4: reserved */
177 case 5: /* 6 Mbps */
178 return 12;
179 case 6: /* 9 Mbps */
180 return 18;
181 case 7: /* 12 Mbps */
182 return 24;
183 case 8: /* 18 Mbps */
184 return 36;
185 case 9: /* 24 Mbps */
186 return 48;
187 case 10: /* 36 Mbps */
188 return 72;
189 case 11: /* 48 Mbps */
190 return 96;
191 case 12: /* 54 Mbps */
192 return 108;
193 }
194 pr_alert("Invalid Marvell WLAN rate %i\n", rate);
195 return 0;
196 }
197
198 /**
199 * process_rxed_802_11_packet - processes a received 802.11 packet and forwards
200 * it to kernel/upper layer
201 *
202 * @priv: A pointer to &struct lbs_private
203 * @skb: A pointer to skb which includes the received packet
204 * returns: 0 or -1
205 */
process_rxed_802_11_packet(struct lbs_private * priv,struct sk_buff * skb)206 static int process_rxed_802_11_packet(struct lbs_private *priv,
207 struct sk_buff *skb)
208 {
209 int ret = 0;
210 struct net_device *dev = priv->dev;
211 struct rx80211packethdr *p_rx_pkt;
212 struct rxpd *prxpd;
213 struct rx_radiotap_hdr radiotap_hdr;
214 struct rx_radiotap_hdr *pradiotap_hdr;
215
216 p_rx_pkt = (struct rx80211packethdr *) skb->data;
217 prxpd = &p_rx_pkt->rx_pd;
218
219 /* lbs_deb_hex(LBS_DEB_RX, "RX Data: Before chop rxpd", skb->data, min(skb->len, 100)); */
220
221 if (skb->len < (ETH_HLEN + 8 + sizeof(struct rxpd))) {
222 lbs_deb_rx("rx err: frame received with bad length\n");
223 dev->stats.rx_length_errors++;
224 ret = -EINVAL;
225 kfree_skb(skb);
226 goto done;
227 }
228
229 lbs_deb_rx("rx data: skb->len-sizeof(RxPd) = %d-%zd = %zd\n",
230 skb->len, sizeof(struct rxpd), skb->len - sizeof(struct rxpd));
231
232 /* create the exported radio header */
233
234 /* radiotap header */
235 memset(&radiotap_hdr, 0, sizeof(radiotap_hdr));
236 /* XXX must check radiotap_hdr.hdr.it_pad for pad */
237 radiotap_hdr.hdr.it_len = cpu_to_le16 (sizeof(struct rx_radiotap_hdr));
238 radiotap_hdr.hdr.it_present = cpu_to_le32 (RX_RADIOTAP_PRESENT);
239 radiotap_hdr.rate = convert_mv_rate_to_radiotap(prxpd->rx_rate);
240 /* XXX must check no carryout */
241 radiotap_hdr.antsignal = prxpd->snr + prxpd->nf;
242
243 /* chop the rxpd */
244 skb_pull(skb, sizeof(struct rxpd));
245
246 /* add space for the new radio header */
247 if ((skb_headroom(skb) < sizeof(struct rx_radiotap_hdr)) &&
248 pskb_expand_head(skb, sizeof(struct rx_radiotap_hdr), 0, GFP_ATOMIC)) {
249 netdev_alert(dev, "%s: couldn't pskb_expand_head\n", __func__);
250 ret = -ENOMEM;
251 kfree_skb(skb);
252 goto done;
253 }
254
255 pradiotap_hdr = skb_push(skb, sizeof(struct rx_radiotap_hdr));
256 memcpy(pradiotap_hdr, &radiotap_hdr, sizeof(struct rx_radiotap_hdr));
257
258 priv->cur_rate = lbs_fw_index_to_data_rate(prxpd->rx_rate);
259
260 lbs_deb_rx("rx data: size of actual packet %d\n", skb->len);
261 dev->stats.rx_bytes += skb->len;
262 dev->stats.rx_packets++;
263
264 skb->protocol = eth_type_trans(skb, priv->dev);
265 netif_rx(skb);
266
267 ret = 0;
268
269 done:
270 return ret;
271 }
272