1/* Helpers for managing scan queues
  2 *
  3 * See copyright notice in main.c
  4 */
  5
  6#include <linux/gfp.h>
  7#include <linux/kernel.h>
  8#include <linux/string.h>
  9#include <linux/ieee80211.h>
 10#include <net/cfg80211.h>
 11
 12#include "hermes.h"
 13#include "orinoco.h"
 14#include "main.h"
 15
 16#include "scan.h"
 17
 18#define ZERO_DBM_OFFSET 0x95
 19#define MAX_SIGNAL_LEVEL 0x8A
 20#define MIN_SIGNAL_LEVEL 0x2F
 21
 22#define SIGNAL_TO_DBM(x)					\
 23	(clamp_t(s32, (x), MIN_SIGNAL_LEVEL, MAX_SIGNAL_LEVEL)	\
 24	 - ZERO_DBM_OFFSET)
 25#define SIGNAL_TO_MBM(x) (SIGNAL_TO_DBM(x) * 100)
 26
 27static int symbol_build_supp_rates(u8 *buf, const __le16 *rates)
 28{
 29	int i;
 30	u8 rate;
 31
 32	buf[0] = WLAN_EID_SUPP_RATES;
 33	for (i = 0; i < 5; i++) {
 34		rate = le16_to_cpu(rates[i]);
 35		/* NULL terminated */
 36		if (rate == 0x0)
 37			break;
 38		buf[i + 2] = rate;
 39	}
 40	buf[1] = i;
 41
 42	return i + 2;
 43}
 44
 45static int prism_build_supp_rates(u8 *buf, const u8 *rates)
 46{
 47	int i;
 48
 49	buf[0] = WLAN_EID_SUPP_RATES;
 50	for (i = 0; i < 8; i++) {
 51		/* NULL terminated */
 52		if (rates[i] == 0x0)
 53			break;
 54		buf[i + 2] = rates[i];
 55	}
 56	buf[1] = i;
 57
 58	/* We might still have another 2 rates, which need to go in
 59	 * extended supported rates */
 60	if (i == 8 && rates[i] > 0) {
 61		buf[10] = WLAN_EID_EXT_SUPP_RATES;
 62		for (; i < 10; i++) {
 63			/* NULL terminated */
 64			if (rates[i] == 0x0)
 65				break;
 66			buf[i + 2] = rates[i];
 67		}
 68		buf[11] = i - 8;
 69	}
 70
 71	return (i < 8) ? i + 2 : i + 4;
 72}
 73
 74static void orinoco_add_hostscan_result(struct orinoco_private *priv,
 75					const union hermes_scan_info *bss)
 76{
 77	struct wiphy *wiphy = priv_to_wiphy(priv);
 78	struct ieee80211_channel *channel;
 79	struct cfg80211_bss *cbss;
 80	u8 *ie;
 81	u8 ie_buf[46];
 82	u64 timestamp;
 83	s32 signal;
 84	u16 capability;
 85	u16 beacon_interval;
 86	int ie_len;
 87	int freq;
 88	int len;
 89
 90	len = le16_to_cpu(bss->a.essid_len);
 91
 92	/* Reconstruct SSID and bitrate IEs to pass up */
 93	ie_buf[0] = WLAN_EID_SSID;
 94	ie_buf[1] = len;
 95	memcpy(&ie_buf[2], bss->a.essid, len);
 96
 97	ie = ie_buf + len + 2;
 98	ie_len = ie_buf[1] + 2;
 99	switch (priv->firmware_type) {
100	case FIRMWARE_TYPE_SYMBOL:
101		ie_len += symbol_build_supp_rates(ie, bss->s.rates);
102		break;
103
104	case FIRMWARE_TYPE_INTERSIL:
105		ie_len += prism_build_supp_rates(ie, bss->p.rates);
106		break;
107
108	case FIRMWARE_TYPE_AGERE:
109	default:
110		break;
111	}
112
113	freq = ieee80211_channel_to_frequency(
114		le16_to_cpu(bss->a.channel), IEEE80211_BAND_2GHZ);
115	channel = ieee80211_get_channel(wiphy, freq);
116	if (!channel) {
117		printk(KERN_DEBUG "Invalid channel designation %04X(%04X)",
118			bss->a.channel, freq);
119		return;	/* Then ignore it for now */
120	}
121	timestamp = 0;
122	capability = le16_to_cpu(bss->a.capabilities);
123	beacon_interval = le16_to_cpu(bss->a.beacon_interv);
124	signal = SIGNAL_TO_MBM(le16_to_cpu(bss->a.level));
125
126	cbss = cfg80211_inform_bss(wiphy, channel, bss->a.bssid, timestamp,
127				   capability, beacon_interval, ie_buf, ie_len,
128				   signal, GFP_KERNEL);
129	cfg80211_put_bss(wiphy, cbss);
130}
131
132void orinoco_add_extscan_result(struct orinoco_private *priv,
133				struct agere_ext_scan_info *bss,
134				size_t len)
135{
136	struct wiphy *wiphy = priv_to_wiphy(priv);
137	struct ieee80211_channel *channel;
138	struct cfg80211_bss *cbss;
139	const u8 *ie;
140	u64 timestamp;
141	s32 signal;
142	u16 capability;
143	u16 beacon_interval;
144	size_t ie_len;
145	int chan, freq;
146
147	ie_len = len - sizeof(*bss);
148	ie = cfg80211_find_ie(WLAN_EID_DS_PARAMS, bss->data, ie_len);
149	chan = ie ? ie[2] : 0;
150	freq = ieee80211_channel_to_frequency(chan, IEEE80211_BAND_2GHZ);
151	channel = ieee80211_get_channel(wiphy, freq);
152
153	timestamp = le64_to_cpu(bss->timestamp);
154	capability = le16_to_cpu(bss->capabilities);
155	beacon_interval = le16_to_cpu(bss->beacon_interval);
156	ie = bss->data;
157	signal = SIGNAL_TO_MBM(bss->level);
158
159	cbss = cfg80211_inform_bss(wiphy, channel, bss->bssid, timestamp,
160				   capability, beacon_interval, ie, ie_len,
161				   signal, GFP_KERNEL);
162	cfg80211_put_bss(wiphy, cbss);
163}
164
165void orinoco_add_hostscan_results(struct orinoco_private *priv,
166				  unsigned char *buf,
167				  size_t len)
168{
169	int offset;		/* In the scan data */
170	size_t atom_len;
171	bool abort = false;
172
173	switch (priv->firmware_type) {
174	case FIRMWARE_TYPE_AGERE:
175		atom_len = sizeof(struct agere_scan_apinfo);
176		offset = 0;
177		break;
178
179	case FIRMWARE_TYPE_SYMBOL:
180		/* Lack of documentation necessitates this hack.
181		 * Different firmwares have 68 or 76 byte long atoms.
182		 * We try modulo first.  If the length divides by both,
183		 * we check what would be the channel in the second
184		 * frame for a 68-byte atom.  76-byte atoms have 0 there.
185		 * Valid channel cannot be 0.  */
186		if (len % 76)
187			atom_len = 68;
188		else if (len % 68)
189			atom_len = 76;
190		else if (len >= 1292 && buf[68] == 0)
191			atom_len = 76;
192		else
193			atom_len = 68;
194		offset = 0;
195		break;
196
197	case FIRMWARE_TYPE_INTERSIL:
198		offset = 4;
199		if (priv->has_hostscan) {
200			atom_len = le16_to_cpup((__le16 *)buf);
201			/* Sanity check for atom_len */
202			if (atom_len < sizeof(struct prism2_scan_apinfo)) {
203				printk(KERN_ERR "%s: Invalid atom_len in scan "
204				       "data: %zu\n", priv->ndev->name,
205				       atom_len);
206				abort = true;
207				goto scan_abort;
208			}
209		} else
210			atom_len = offsetof(struct prism2_scan_apinfo, atim);
211		break;
212
213	default:
214		abort = true;
215		goto scan_abort;
216	}
217
218	/* Check that we got an whole number of atoms */
219	if ((len - offset) % atom_len) {
220		printk(KERN_ERR "%s: Unexpected scan data length %zu, "
221		       "atom_len %zu, offset %d\n", priv->ndev->name, len,
222		       atom_len, offset);
223		abort = true;
224		goto scan_abort;
225	}
226
227	/* Process the entries one by one */
228	for (; offset + atom_len <= len; offset += atom_len) {
229		union hermes_scan_info *atom;
230
231		atom = (union hermes_scan_info *) (buf + offset);
232
233		orinoco_add_hostscan_result(priv, atom);
234	}
235
236 scan_abort:
237	if (priv->scan_request) {
238		cfg80211_scan_done(priv->scan_request, abort);
239		priv->scan_request = NULL;
240	}
241}
242
243void orinoco_scan_done(struct orinoco_private *priv, bool abort)
244{
245	if (priv->scan_request) {
246		cfg80211_scan_done(priv->scan_request, abort);
247		priv->scan_request = NULL;
248	}
249}