cfg80211: introduce scan IE limit attribute
This patch introduces a new attribute for a wiphy that tells
userspace how long the information elements added to a probe
request frame can be at most. It also updates the at76 to
advertise that it cannot support that, and, for now until I
can fix that, iwlwifi too.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/at76c50x-usb.c b/drivers/net/wireless/at76c50x-usb.c
index 69248de..55f947a 100644
--- a/drivers/net/wireless/at76c50x-usb.c
+++ b/drivers/net/wireless/at76c50x-usb.c
@@ -2250,6 +2250,7 @@
/* mac80211 initialisation */
priv->hw->wiphy->max_scan_ssids = 1;
+ priv->hw->wiphy->max_scan_ie_len = 0;
priv->hw->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
priv->hw->wiphy->bands[IEEE80211_BAND_2GHZ] = &at76_supported_band;
priv->hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 82abb1f..ef55f91 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -1306,6 +1306,7 @@
hw->wiphy->custom_regulatory = true;
hw->wiphy->max_scan_ssids = 1;
+ hw->wiphy->max_scan_ie_len = 0; /* XXX for now */
/* Default value; 4 EDCA QOS priorities */
hw->queues = 4;
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 27f230f..209cace 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -390,6 +390,8 @@
*
* @NL80211_ATTR_MAX_NUM_SCAN_SSIDS: number of SSIDs you can scan with
* a single scan request, a wiphy attribute.
+ * @NL80211_ATTR_MAX_SCAN_IE_LEN: maximum length of information elements
+ * that can be added to a scan request
*
* @NL80211_ATTR_SCAN_FREQUENCIES: nested attribute with frequencies (in MHz)
* @NL80211_ATTR_SCAN_SSIDS: nested attribute with SSIDs, leave out for passive
@@ -507,6 +509,8 @@
NL80211_ATTR_KEY_TYPE,
+ NL80211_ATTR_MAX_SCAN_IE_LEN,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
diff --git a/include/net/wireless.h b/include/net/wireless.h
index 64a7620..2bcdeda 100644
--- a/include/net/wireless.h
+++ b/include/net/wireless.h
@@ -222,6 +222,7 @@
int bss_priv_size;
u8 max_scan_ssids;
+ u16 max_scan_ie_len;
/* If multiple wiphys are registered and you're handed e.g.
* a regular netdev with assigned ieee80211_ptr, you won't
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index fbcbed6..ee58a78 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -728,7 +728,18 @@
return NULL;
wiphy->privid = mac80211_wiphy_privid;
- wiphy->max_scan_ssids = 4;
+
+ if (!ops->hw_scan) {
+ /* For hw_scan, driver needs to set these up. */
+ wiphy->max_scan_ssids = 4;
+
+ /* we support a maximum of 32 rates in cfg80211 */
+ wiphy->max_scan_ie_len = IEEE80211_MAX_DATA_LEN
+ - 2 - 32 /* SSID */
+ - 4 - 32 /* (ext) supp rates */;
+
+ }
+
/* Yes, putting cfg80211_bss into ieee80211_bss is a hack */
wiphy->bss_priv_size = sizeof(struct ieee80211_bss) -
sizeof(struct cfg80211_bss);
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index fdf432f..05caf34 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -890,6 +890,8 @@
*pos = rate->bitrate / 5;
}
+ /* if adding more here, adjust max_scan_ie_len */
+
if (ie)
memcpy(skb_put(skb, ie_len), ie, ie_len);
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 1394115..447fa17 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -181,6 +181,8 @@
NLA_PUT_STRING(msg, NL80211_ATTR_WIPHY_NAME, wiphy_name(&dev->wiphy));
NLA_PUT_U8(msg, NL80211_ATTR_MAX_NUM_SCAN_SSIDS,
dev->wiphy.max_scan_ssids);
+ NLA_PUT_U16(msg, NL80211_ATTR_MAX_SCAN_IE_LEN,
+ dev->wiphy.max_scan_ie_len);
nl_modes = nla_nest_start(msg, NL80211_ATTR_SUPPORTED_IFTYPES);
if (!nl_modes)
@@ -2528,6 +2530,11 @@
else
ie_len = 0;
+ if (ie_len > wiphy->max_scan_ie_len) {
+ err = -EINVAL;
+ goto out;
+ }
+
request = kzalloc(sizeof(*request)
+ sizeof(*ssid) * n_ssids
+ sizeof(channel) * n_channels