linux/drivers/net/wireless/orinoco/scan.c
Joe Gunn 46c2cb8cae orinoco: Drop scan results with unknown channels
If the frequency can not be mapped to a channel structure log it and drop it.

Signed-off-by: Joseph J. Gunn <armadefuego@yahoo.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-02-25 15:33:38 -05:00

245 lines
5.6 KiB
C

/* Helpers for managing scan queues
*
* See copyright notice in main.c
*/
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/ieee80211.h>
#include <net/cfg80211.h>
#include "hermes.h"
#include "orinoco.h"
#include "main.h"
#include "scan.h"
#define ZERO_DBM_OFFSET 0x95
#define MAX_SIGNAL_LEVEL 0x8A
#define MIN_SIGNAL_LEVEL 0x2F
#define SIGNAL_TO_DBM(x) \
(clamp_t(s32, (x), MIN_SIGNAL_LEVEL, MAX_SIGNAL_LEVEL) \
- ZERO_DBM_OFFSET)
#define SIGNAL_TO_MBM(x) (SIGNAL_TO_DBM(x) * 100)
static int symbol_build_supp_rates(u8 *buf, const __le16 *rates)
{
int i;
u8 rate;
buf[0] = WLAN_EID_SUPP_RATES;
for (i = 0; i < 5; i++) {
rate = le16_to_cpu(rates[i]);
/* NULL terminated */
if (rate == 0x0)
break;
buf[i + 2] = rate;
}
buf[1] = i;
return i + 2;
}
static int prism_build_supp_rates(u8 *buf, const u8 *rates)
{
int i;
buf[0] = WLAN_EID_SUPP_RATES;
for (i = 0; i < 8; i++) {
/* NULL terminated */
if (rates[i] == 0x0)
break;
buf[i + 2] = rates[i];
}
buf[1] = i;
/* We might still have another 2 rates, which need to go in
* extended supported rates */
if (i == 8 && rates[i] > 0) {
buf[10] = WLAN_EID_EXT_SUPP_RATES;
for (; i < 10; i++) {
/* NULL terminated */
if (rates[i] == 0x0)
break;
buf[i + 2] = rates[i];
}
buf[11] = i - 8;
}
return (i < 8) ? i + 2 : i + 4;
}
static void orinoco_add_hostscan_result(struct orinoco_private *priv,
const union hermes_scan_info *bss)
{
struct wiphy *wiphy = priv_to_wiphy(priv);
struct ieee80211_channel *channel;
u8 *ie;
u8 ie_buf[46];
u64 timestamp;
s32 signal;
u16 capability;
u16 beacon_interval;
int ie_len;
int freq;
int len;
len = le16_to_cpu(bss->a.essid_len);
/* Reconstruct SSID and bitrate IEs to pass up */
ie_buf[0] = WLAN_EID_SSID;
ie_buf[1] = len;
memcpy(&ie_buf[2], bss->a.essid, len);
ie = ie_buf + len + 2;
ie_len = ie_buf[1] + 2;
switch (priv->firmware_type) {
case FIRMWARE_TYPE_SYMBOL:
ie_len += symbol_build_supp_rates(ie, bss->s.rates);
break;
case FIRMWARE_TYPE_INTERSIL:
ie_len += prism_build_supp_rates(ie, bss->p.rates);
break;
case FIRMWARE_TYPE_AGERE:
default:
break;
}
freq = ieee80211_dsss_chan_to_freq(le16_to_cpu(bss->a.channel));
channel = ieee80211_get_channel(wiphy, freq);
if (!channel) {
printk(KERN_DEBUG "Invalid channel designation %04X(%04X)",
bss->a.channel, freq);
return; /* Then ignore it for now */
}
timestamp = 0;
capability = le16_to_cpu(bss->a.capabilities);
beacon_interval = le16_to_cpu(bss->a.beacon_interv);
signal = SIGNAL_TO_MBM(le16_to_cpu(bss->a.level));
cfg80211_inform_bss(wiphy, channel, bss->a.bssid, timestamp,
capability, beacon_interval, ie_buf, ie_len,
signal, GFP_KERNEL);
}
void orinoco_add_extscan_result(struct orinoco_private *priv,
struct agere_ext_scan_info *bss,
size_t len)
{
struct wiphy *wiphy = priv_to_wiphy(priv);
struct ieee80211_channel *channel;
const u8 *ie;
u64 timestamp;
s32 signal;
u16 capability;
u16 beacon_interval;
size_t ie_len;
int chan, freq;
ie_len = len - sizeof(*bss);
ie = cfg80211_find_ie(WLAN_EID_DS_PARAMS, bss->data, ie_len);
chan = ie ? ie[2] : 0;
freq = ieee80211_dsss_chan_to_freq(chan);
channel = ieee80211_get_channel(wiphy, freq);
timestamp = le64_to_cpu(bss->timestamp);
capability = le16_to_cpu(bss->capabilities);
beacon_interval = le16_to_cpu(bss->beacon_interval);
ie = bss->data;
signal = SIGNAL_TO_MBM(bss->level);
cfg80211_inform_bss(wiphy, channel, bss->bssid, timestamp,
capability, beacon_interval, ie, ie_len,
signal, GFP_KERNEL);
}
void orinoco_add_hostscan_results(struct orinoco_private *priv,
unsigned char *buf,
size_t len)
{
int offset; /* In the scan data */
size_t atom_len;
bool abort = false;
switch (priv->firmware_type) {
case FIRMWARE_TYPE_AGERE:
atom_len = sizeof(struct agere_scan_apinfo);
offset = 0;
break;
case FIRMWARE_TYPE_SYMBOL:
/* Lack of documentation necessitates this hack.
* Different firmwares have 68 or 76 byte long atoms.
* We try modulo first. If the length divides by both,
* we check what would be the channel in the second
* frame for a 68-byte atom. 76-byte atoms have 0 there.
* Valid channel cannot be 0. */
if (len % 76)
atom_len = 68;
else if (len % 68)
atom_len = 76;
else if (len >= 1292 && buf[68] == 0)
atom_len = 76;
else
atom_len = 68;
offset = 0;
break;
case FIRMWARE_TYPE_INTERSIL:
offset = 4;
if (priv->has_hostscan) {
atom_len = le16_to_cpup((__le16 *)buf);
/* Sanity check for atom_len */
if (atom_len < sizeof(struct prism2_scan_apinfo)) {
printk(KERN_ERR "%s: Invalid atom_len in scan "
"data: %zu\n", priv->ndev->name,
atom_len);
abort = true;
goto scan_abort;
}
} else
atom_len = offsetof(struct prism2_scan_apinfo, atim);
break;
default:
abort = true;
goto scan_abort;
}
/* Check that we got an whole number of atoms */
if ((len - offset) % atom_len) {
printk(KERN_ERR "%s: Unexpected scan data length %zu, "
"atom_len %zu, offset %d\n", priv->ndev->name, len,
atom_len, offset);
abort = true;
goto scan_abort;
}
/* Process the entries one by one */
for (; offset + atom_len <= len; offset += atom_len) {
union hermes_scan_info *atom;
atom = (union hermes_scan_info *) (buf + offset);
orinoco_add_hostscan_result(priv, atom);
}
scan_abort:
if (priv->scan_request) {
cfg80211_scan_done(priv->scan_request, abort);
priv->scan_request = NULL;
}
}
void orinoco_scan_done(struct orinoco_private *priv, bool abort)
{
if (priv->scan_request) {
cfg80211_scan_done(priv->scan_request, abort);
priv->scan_request = NULL;
}
}