This patch includes modifications in hostapd to generate beacons and
probe response packets with Power Constraint IE.
This patch is based on the initial design RFC proposed with subject
"[RFC - v1 - design doc] hostapd: Beacon generation with Power
Constraint IE - 11h TPC".
Changes from the proposed design:
------------------------------------------------
Design document proposes to imply TPC only for devices operating in
U-NII 2 band. As per further analysis of beacons transmitted by Netgear,
CISCO APs and few other APs in 802.11A mode, the power constraint IE is
also included in beacons transmitted in U-NII 1, U-NII 3 bands. Hence
power constraint IE is included in all beacons/probe response packets
for devices operating in 80211A mode (without restricting to U-NII 2
band) and with 80211h flag enabled in hostapd.config
Signed-off-by: Srinivasan <srinivasanb@xxxxxxxxxxx>
---
hostapd/config_file.c | 8 ++++++++
hostapd/hostapd.conf | 5 +++++
src/ap/ap_config.h | 3 +++
src/ap/beacon.c | 30 ++++++++++++++++++++++++++++++
src/ap/ieee802_11.c | 5 +++++
5 files changed, 51 insertions(+), 0 deletions(-)
diff --git a/hostapd/config_file.c b/hostapd/config_file.c
index 7b22dfd..b6a3b6e 100644
--- a/hostapd/config_file.c
+++ b/hostapd/config_file.c
@@ -1224,6 +1224,12 @@ static int hostapd_config_check(struct
hostapd_config *conf)
return -1;
}
+ if (conf->ieee80211h && !conf->ieee80211d) {
+ wpa_printf(MSG_ERROR, "Cannot enable IEEE 802.11h without "
+ "enabling 802.11d ");
+ return -1;
+ }
+
for (i = 0; i < conf->num_bss; i++) {
if (hostapd_config_check_bss(&conf->bss[i], conf))
return -1;
@@ -1785,6 +1791,8 @@ static int hostapd_config_fill(struct
hostapd_config *conf,
conf->country[2] = ' ';
} else if (os_strcmp(buf, "ieee80211d") == 0) {
conf->ieee80211d = atoi(pos);
+ } else if (os_strcmp(buf, "ieee80211h") == 0) {
+ conf->ieee80211h = atoi(pos);
} else if (os_strcmp(buf, "ieee8021x") == 0) {
bss->ieee802_1x = atoi(pos);
} else if (os_strcmp(buf, "eapol_version") == 0) {
diff --git a/hostapd/hostapd.conf b/hostapd/hostapd.conf
index eca3996..759489f 100644
--- a/hostapd/hostapd.conf
+++ b/hostapd/hostapd.conf
@@ -105,6 +105,11 @@ ssid=test
# (default: 0 = disabled)
#ieee80211d=1
+# Enable IEEE 802.11h. This is a partial support for 802.11h which
+# includes Power Constraint IE in beacon and prb response.
+# (default: 0 = disabled)
+#ieee80211h=1
+
# Operation mode (a = IEEE 802.11a, b = IEEE 802.11b, g = IEEE 802.11g,
# ad = IEEE 802.11ad (60 GHz); a/g options are used with IEEE 802.11n,
too, to
# specify band)
diff --git a/src/ap/ap_config.h b/src/ap/ap_config.h
index 4742107..a0624b9 100644
--- a/src/ap/ap_config.h
+++ b/src/ap/ap_config.h
@@ -460,6 +460,8 @@ struct hostapd_bss_config {
int *sae_groups;
};
+/* Default value for pwr constraint */
+#define DEFAULT_PWR_CONSTRAINT 0
/**
* struct hostapd_config - Per-radio interface configuration
@@ -495,6 +497,7 @@ struct hostapd_config {
*/
int ieee80211d;
+ int ieee80211h;
struct hostapd_tx_queue_params tx_queue[NUM_TX_QUEUES];
diff --git a/src/ap/beacon.c b/src/ap/beacon.c
index 4c47c75..9749d45 100644
--- a/src/ap/beacon.c
+++ b/src/ap/beacon.c
@@ -172,6 +172,30 @@ static u8 * hostapd_eid_country(struct hostapd_data
*hapd, u8 *eid,
return pos;
}
+static u8 * hostapd_eid_pwr_constraint(struct hostapd_data *hapd, u8 *eid)
+{
+ u8 *pos = eid;
+
+ if (!hapd->iconf->ieee80211h ||
+ hapd->iface->current_mode == NULL ||
+ hapd->iface->current_mode->mode != HOSTAPD_MODE_IEEE80211A)
+ return eid;
+
+ /* CRDA provides reduced TX power than actual regulatory max TX power.
+ * Value of 0 to the Local Power constraint provides an opportunity
+ * for the client devices to operate at Power Limit provided by CRDA
+ * (for client devices
+ * "Local max TX pwr" = regul max TX pwr - Local pwr constraint)*/
+
+ /* Element ID */
+ *pos++ = WLAN_EID_PWR_CONSTRAINT;
+ /* Length */
+ *pos++ = 1;
+ /* Local Power Constraint */
+ *pos++ = DEFAULT_PWR_CONSTRAINT;
+
+ return pos;
+}
static u8 * hostapd_eid_wpa(struct hostapd_data *hapd, u8 *eid, size_t
len)
{
@@ -242,6 +266,9 @@ static u8 * hostapd_gen_probe_resp(struct
hostapd_data *hapd,
pos = hostapd_eid_country(hapd, pos, epos - pos);
+ /* Power Constraint element */
+ pos = hostapd_eid_pwr_constraint(hapd, pos);
+
/* ERP Information element */
pos = hostapd_eid_erp_info(hapd, pos);
@@ -631,6 +658,9 @@ void ieee802_11_set_beacon(struct hostapd_data *hapd)
tailpos = hostapd_eid_country(hapd, tailpos,
tail + BEACON_TAIL_BUF_SIZE - tailpos);
+ /* Power Constraint element */
+ tailpos = hostapd_eid_pwr_constraint(hapd, tailpos);
+
/* ERP Information element */
tailpos = hostapd_eid_erp_info(hapd, tailpos);
diff --git a/src/ap/ieee802_11.c b/src/ap/ieee802_11.c
index 79235df..2a4f758 100644
--- a/src/ap/ieee802_11.c
+++ b/src/ap/ieee802_11.c
@@ -175,6 +175,11 @@ u16 hostapd_own_capab_info(struct hostapd_data
*hapd, struct sta_info *sta,
hapd->iface->num_sta_no_short_slot_time == 0)
capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
+ /* To Do: Also consider driver support for DFS to set Spectrum Mgmt*/
+ if (hapd->iface->current_mode &&
+ hapd->iface->current_mode->mode == HOSTAPD_MODE_IEEE80211A &&
+ hapd->iconf->ieee80211h)
+ capab |= WLAN_CAPABILITY_SPECTRUM_MGMT;
return capab;
}
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
