mac80211: 802.11w - Implement Association Comeback processing
When MFP is enabled, the AP does not allow a STA to associate if an
existing security association exists without first going through SA
Query process. When this happens, the association request is denied
with a new status code ("temporarily rejected") ans Association
Comeback IE is used to notify when the association may be tried again
(i.e., when the SA Query procedure has timed out).
Use the comeback time to update the mac80211 client MLME timer for
next association attempt to minimize waiting time if association is
temporarily rejected.
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index 9fe1948d..7800e20 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -914,6 +914,9 @@
/* 802.11g */
WLAN_STATUS_ASSOC_DENIED_NOSHORTTIME = 25,
WLAN_STATUS_ASSOC_DENIED_NODSSSOFDM = 26,
+ /* 802.11w */
+ WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY = 30,
+ WLAN_STATUS_ROBUST_MGMT_FRAME_POLICY_VIOLATION = 31,
/* 802.11i */
WLAN_STATUS_INVALID_IE = 40,
WLAN_STATUS_INVALID_GROUP_CIPHER = 41,
@@ -1034,6 +1037,7 @@
/* 802.11i */
WLAN_EID_RSN = 48,
WLAN_EID_MMIE = 76 /* 802.11w */,
+ WLAN_EID_ASSOC_COMEBACK_TIME = 77,
WLAN_EID_WPA = 221,
WLAN_EID_GENERIC = 221,
WLAN_EID_VENDOR_SPECIFIC = 221,
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 212c732..9112c52 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -820,6 +820,7 @@
u8 *country_elem;
u8 *pwr_constr_elem;
u8 *quiet_elem; /* first quite element */
+ u8 *assoc_comeback;
/* length of them, respectively */
u8 ssid_len;
@@ -847,6 +848,7 @@
u8 pwr_constr_elem_len;
u8 quiet_elem_len;
u8 num_of_quiet_elem; /* can be more the one */
+ u8 assoc_comeback_len;
};
static inline struct ieee80211_local *hw_to_local(
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 42c5f98..82c598a 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1275,6 +1275,23 @@
sdata->dev->name, reassoc ? "Rea" : "A", mgmt->sa,
capab_info, status_code, (u16)(aid & ~(BIT(15) | BIT(14))));
+ pos = mgmt->u.assoc_resp.variable;
+ ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
+
+ if (status_code == WLAN_STATUS_ASSOC_REJECTED_TEMPORARILY &&
+ elems.assoc_comeback && elems.assoc_comeback_len == 4) {
+ u32 tu, ms;
+ tu = get_unaligned_le32(elems.assoc_comeback);
+ ms = tu * 1024 / 1000;
+ printk(KERN_DEBUG "%s: AP rejected association temporarily; "
+ "comeback duration %u TU (%u ms)\n",
+ sdata->dev->name, tu, ms);
+ if (ms > IEEE80211_ASSOC_TIMEOUT)
+ mod_timer(&ifsta->timer,
+ jiffies + msecs_to_jiffies(ms));
+ return;
+ }
+
if (status_code != WLAN_STATUS_SUCCESS) {
printk(KERN_DEBUG "%s: AP denied association (code=%d)\n",
sdata->dev->name, status_code);
@@ -1290,9 +1307,6 @@
"set\n", sdata->dev->name, aid);
aid &= ~(BIT(15) | BIT(14));
- pos = mgmt->u.assoc_resp.variable;
- ieee802_11_parse_elems(pos, len - (pos - (u8 *) mgmt), &elems);
-
if (!elems.supp_rates) {
printk(KERN_DEBUG "%s: no SuppRates element in AssocResp\n",
sdata->dev->name);
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 5cd4303..963e047 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -653,6 +653,10 @@
elems->pwr_constr_elem = pos;
elems->pwr_constr_elem_len = elen;
break;
+ case WLAN_EID_ASSOC_COMEBACK_TIME:
+ elems->assoc_comeback = pos;
+ elems->assoc_comeback_len = elen;
+ break;
default:
break;
}