[PATCH v3] hostap: Support ht-cap over-rides.

greearb at candelatech.com greearb at candelatech.com
Tue Nov 22 15:37:40 EST 2011


From: Ben Greear <greearb at candelatech.com>

This allows ht-capabilities over-rides on kernels that
support these features.

MCS Rates can be disabled (ie, to force to slower
speeds when using /n).  Rates cannot be forced
higher.

HT can be disabled, forcing an /a/b/g/n station to act like
an /a/b/g station.

HT40 can be disabled.

MAX-AMSDU can be disabled
AMPDU-Factor and AMPDU Density can be modified.

Please note that these are suggestions to the kernel.  Only
mac80211 drivers will work at all.  The AMPDU-Factor
can only be decreased and the AMPDU-Density can only
be increased currently.

Signed-hostap: Ben Greear <greearb at candelatech.com>
---

v3:  Sync'd with upstream netlink attributes
     Moved configurables into the network {} sections.
     Compile out the code by default.

Still needs some additional documentation, but I want to make sure
the code is at least mostly right before doing that.

:100644 100644 3014762... 860396f... M	src/common/ieee802_11_defs.h
:100644 100644 ce25d03... 78fedea... M	src/drivers/driver.h
:100644 100644 7943595... 9b8df69... M	src/drivers/driver_nl80211.c
:100644 100644 f9261c2... a8028dd... M	src/drivers/nl80211_copy.h
:100644 100644 5ec7207... 7dda785... M	wpa_supplicant/Makefile
:100644 100644 b446a3f... 35f446d... M	wpa_supplicant/config.c
:100644 100644 ae496ff... 899aecb... M	wpa_supplicant/config.h
:100644 100644 8419f43... 2f4193f... M	wpa_supplicant/config_ssid.h
:100644 100644 03a4223... 862f645... M	wpa_supplicant/defconfig
:100644 100644 3416d68... 9e4044f... M	wpa_supplicant/sme.c
:100644 100644 2b3140e... ceee620... M	wpa_supplicant/wpa_supplicant.c
:100644 100644 59fc9a3... 6d4643d... M	wpa_supplicant/wpa_supplicant_i.h
 src/common/ieee802_11_defs.h      |    1 +
 src/drivers/driver.h              |   16 ++++
 src/drivers/driver_nl80211.c      |   20 +++++
 src/drivers/nl80211_copy.h        |    5 +
 wpa_supplicant/Makefile           |    4 +
 wpa_supplicant/config.c           |   19 +++++
 wpa_supplicant/config.h           |    5 +
 wpa_supplicant/config_ssid.h      |   49 +++++++++++
 wpa_supplicant/defconfig          |    3 +
 wpa_supplicant/sme.c              |    1 +
 wpa_supplicant/wpa_supplicant.c   |  159 +++++++++++++++++++++++++++++++++++++
 wpa_supplicant/wpa_supplicant_i.h |   27 ++++++
 12 files changed, 309 insertions(+), 0 deletions(-)

diff --git a/src/common/ieee802_11_defs.h b/src/common/ieee802_11_defs.h
index 3014762..860396f 100644
--- a/src/common/ieee802_11_defs.h
+++ b/src/common/ieee802_11_defs.h
@@ -519,6 +519,7 @@ struct ieee80211_mgmt {
 } STRUCT_PACKED;
 
 
+#define IEEE80211_HT_MCS_MASK_LEN               10
 struct ieee80211_ht_capabilities {
 	le16 ht_capabilities_info;
 	u8 a_mpdu_params;
diff --git a/src/drivers/driver.h b/src/drivers/driver.h
index ce25d03..78fedea 100644
--- a/src/drivers/driver.h
+++ b/src/drivers/driver.h
@@ -26,6 +26,7 @@
 #define WPA_SUPPLICANT_DRIVER_VERSION 4
 
 #include "common/defs.h"
+#include "common/ieee802_11_defs.h"
 
 #define HOSTAPD_CHAN_DISABLED 0x00000001
 #define HOSTAPD_CHAN_PASSIVE_SCAN 0x00000002
@@ -516,6 +517,21 @@ struct wpa_driver_associate_params {
 	 * STA mode: bits 0..3 UAPSD enabled for VO,VI,BK,BE
 	 */
 	int uapsd;
+
+#ifdef CONFIG_HT_OVERRIDES
+	/**
+	 * disable_ht - Disable HT (802.11n) for this connection.
+	 */
+	int disable_ht;
+
+	/**
+	 * HT Capabilities over-rides.  Only bits set in the mask will be
+	 * used, and not all values are used by the kernel anyway.  Currently,
+	 * MCS, MPDU and MSDU fields are used.
+	 */
+	struct ieee80211_ht_capabilities htcaps;
+	struct ieee80211_ht_capabilities htcaps_mask;
+#endif
 };
 
 enum hide_ssid {
diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
index 7943595..9b8df69 100644
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -5617,6 +5617,16 @@ skip_auth_type:
 		NLA_PUT_U32(msg, NL80211_ATTR_AKM_SUITES, mgmt);
 	}
 
+#ifdef CONFIG_HT_OVERRIDES
+	if (params->disable_ht)
+		NLA_PUT_FLAG(msg, NL80211_ATTR_DISABLE_HT);
+
+	NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY, sizeof(params->htcaps),
+		&params->htcaps);
+	NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY_MASK, sizeof(params->htcaps_mask),
+		&params->htcaps_mask);
+#endif
+
 	ret = nl80211_set_conn_keys(params, msg);
 	if (ret)
 		goto nla_put_failure;
@@ -5764,6 +5774,16 @@ static int wpa_driver_nl80211_associate(
 			params->prev_bssid);
 	}
 
+#ifdef CONFIG_HT_OVERRIDES
+	if (params->disable_ht)
+		NLA_PUT_FLAG(msg, NL80211_ATTR_DISABLE_HT);
+
+	NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY, sizeof(params->htcaps),
+		&params->htcaps);
+	NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY_MASK, sizeof(params->htcaps_mask),
+		&params->htcaps_mask);
+#endif
+
 	if (params->p2p)
 		wpa_printf(MSG_DEBUG, "  * P2P group");
 
diff --git a/src/drivers/nl80211_copy.h b/src/drivers/nl80211_copy.h
index f9261c2..a8028dd 100644
--- a/src/drivers/nl80211_copy.h
+++ b/src/drivers/nl80211_copy.h
@@ -1408,6 +1408,11 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_PROBE_RESP,
 
+	NL80211_ATTR_DFS_REGION,
+
+	NL80211_ATTR_DISABLE_HT,
+	NL80211_ATTR_HT_CAPABILITY_MASK,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
diff --git a/wpa_supplicant/Makefile b/wpa_supplicant/Makefile
index 5ec7207..7dda785 100644
--- a/wpa_supplicant/Makefile
+++ b/wpa_supplicant/Makefile
@@ -111,6 +111,10 @@ ifdef CONFIG_EAPOL_TEST
 CFLAGS += -Werror -DEAPOL_TEST
 endif
 
+ifdef CONFIG_HT_OVERRIDES
+CFLAGS += -DCONFIG_HT_OVERRIDES
+endif
+
 ifndef CONFIG_BACKEND
 CONFIG_BACKEND=file
 endif
diff --git a/wpa_supplicant/config.c b/wpa_supplicant/config.c
index b446a3f..35f446d 100644
--- a/wpa_supplicant/config.c
+++ b/wpa_supplicant/config.c
@@ -1511,6 +1511,14 @@ static const struct parse_data ssid_fields[] = {
 	{ INT_RANGE(frequency, 0, 10000) },
 	{ INT(wpa_ptk_rekey) },
 	{ STR(bgscan) },
+#ifdef CONFIG_HT_OVERRIDES
+	{ INT_RANGE(disable_ht, 0, 1) },
+	{ INT_RANGE(disable_ht40, -1, 1) },
+	{ INT_RANGE(disable_max_amsdu, -1, 1) },
+	{ INT_RANGE(ampdu_factor, -1, 3) },
+	{ INT_RANGE(ampdu_density, -1, 7) },
+	{ STR(ht_mcs) },
+#endif
 };
 
 #undef OFFSET
@@ -1677,6 +1685,9 @@ void wpa_config_free_ssid(struct wpa_ssid *ssid)
 	os_free(ssid->scan_freq);
 	os_free(ssid->freq_list);
 	os_free(ssid->bgscan);
+#ifdef CONFIG_HT_OVERRIDES
+	os_free(ssid->ht_mcs);
+#endif
 	os_free(ssid);
 }
 
@@ -1864,6 +1875,14 @@ void wpa_config_set_network_defaults(struct wpa_ssid *ssid)
 	ssid->eap_workaround = DEFAULT_EAP_WORKAROUND;
 	ssid->eap.fragment_size = DEFAULT_FRAGMENT_SIZE;
 #endif /* IEEE8021X_EAPOL */
+#ifdef CONFIG_HT_OVERRIDES
+	ssid->disable_ht = DEFAULT_DISABLE_HT;
+	ssid->disable_ht40 = DEFAULT_DISABLE_HT40;
+	ssid->disable_max_amsdu = DEFAULT_DISABLE_MAX_AMSDU;
+	ssid->ampdu_factor = DEFAULT_AMPDU_FACTOR;
+	ssid->ampdu_density = DEFAULT_AMPDU_DENSITY;
+	ssid->ht_mcs = strdup("");
+#endif
 }
 
 
diff --git a/wpa_supplicant/config.h b/wpa_supplicant/config.h
index ae496ff..899aecb 100644
--- a/wpa_supplicant/config.h
+++ b/wpa_supplicant/config.h
@@ -15,6 +15,11 @@
 #ifndef CONFIG_H
 #define CONFIG_H
 
+#define DEFAULT_DISABLE_HT 0
+#define DEFAULT_DISABLE_HT40 0
+#define DEFAULT_DISABLE_MAX_AMSDU -1 /* no change */
+#define DEFAULT_AMPDU_FACTOR -1 /* no change */
+#define DEFAULT_AMPDU_DENSITY -1 /* no change */
 #define DEFAULT_EAPOL_VERSION 1
 #ifdef CONFIG_NO_SCAN_PROCESSING
 #define DEFAULT_AP_SCAN 2
diff --git a/wpa_supplicant/config_ssid.h b/wpa_supplicant/config_ssid.h
index 8419f43..2f4193f 100644
--- a/wpa_supplicant/config_ssid.h
+++ b/wpa_supplicant/config_ssid.h
@@ -408,6 +408,55 @@ struct wpa_ssid {
 	 * WPS or similar so that they may be exported.
 	 */
 	int export_keys;
+
+
+#ifdef CONFIG_HT_OVERRIDES
+	/**
+	 * disable_ht - Disable HT (802.11n) for this interface
+	 *
+	 * By default, use it if it is available, but this can be configured
+	 * to 1 to have it disabled.
+	 */
+	int disable_ht;
+
+	/**
+	 * disable_ht40 - Disable HT-40 for this interface
+	 *
+	 * By default, use it if it is available, but this can be configured
+	 * to 1 to have it disabled.
+	 */
+	int disable_ht40;
+
+	/**
+	 * disable_max_amsdu - Disable MAX AMSDU
+	 *
+	 * AMDSU will be 3839 bytes when disabled, or 7935
+	 * when enabled (assuming it is otherwise supported)
+	 * -1 (default) means do not apply any settings to the kernel.
+	 */
+	int disable_max_amsdu;
+
+	/**
+	 * ampdu_factor - Maximum A-MPDU Length Exponent
+	 *
+	 * Value: 0-3, see section 7.3.2.56.3 of the 802.11n-2009 spec.
+	 */
+	int ampdu_factor;
+
+	/**
+	 * ampdu_density - Minum A-MPDU Start Spacing
+	 *
+	 * Value: 0-7, see section 7.3.2.56.3 of the 802.11n-2009 spec.
+	 */
+	int ampdu_density;
+
+	/**
+	 * ht_mcs - Allowed HT-MCS rates, in ascii hex: ffff0000...
+	 *
+	 * By default (empty string):  use whatever the OS has configured.
+	 */
+	char *ht_mcs;
+#endif
 };
 
 #endif /* CONFIG_SSID_H */
diff --git a/wpa_supplicant/defconfig b/wpa_supplicant/defconfig
index 03a4223..862f645 100644
--- a/wpa_supplicant/defconfig
+++ b/wpa_supplicant/defconfig
@@ -217,6 +217,9 @@ CONFIG_SMARTCARD=y
 # Enable this if EAP-SIM or EAP-AKA is included
 #CONFIG_PCSC=y
 
+# Support HT overrides (disable-ht40, mcs rates, etc)
+# CONFIG_HT_OVERRIDES=y
+
 # Development testing
 #CONFIG_EAPOL_TEST=y
 
diff --git a/wpa_supplicant/sme.c b/wpa_supplicant/sme.c
index 3416d68..9e4044f 100644
--- a/wpa_supplicant/sme.c
+++ b/wpa_supplicant/sme.c
@@ -386,6 +386,7 @@ void sme_associate(struct wpa_supplicant *wpa_s, enum wpas_mode mode,
 	params.wpa_ie_len = wpa_s->sme.assoc_req_ie_len;
 	params.pairwise_suite = cipher_suite2driver(wpa_s->pairwise_cipher);
 	params.group_suite = cipher_suite2driver(wpa_s->group_cipher);
+	wpa_supplicant_apply_ht_overrides(wpa_s, &params);
 #ifdef CONFIG_IEEE80211R
 	if (auth_type == WLAN_AUTH_FT && wpa_s->sme.ft_ies) {
 		params.wpa_ie = wpa_s->sme.ft_ies;
diff --git a/wpa_supplicant/wpa_supplicant.c b/wpa_supplicant/wpa_supplicant.c
index 2b3140e..ceee620 100644
--- a/wpa_supplicant/wpa_supplicant.c
+++ b/wpa_supplicant/wpa_supplicant.c
@@ -1425,6 +1425,8 @@ void wpa_supplicant_associate(struct wpa_supplicant *wpa_s,
 	else
 		params.uapsd = -1;
 
+	wpa_supplicant_apply_ht_overrides(wpa_s, &params);
+
 	ret = wpa_drv_associate(wpa_s, &params);
 	if (ret < 0) {
 		wpa_msg(wpa_s, MSG_INFO, "Association request to the driver "
@@ -2165,6 +2167,163 @@ static struct wpa_supplicant * wpa_supplicant_alloc(void)
 	return wpa_s;
 }
 
+#ifdef CONFIG_HT_OVERRIDES
+int wpa_set_htcap_mcs(struct wpa_supplicant *wpa_s,
+		      struct ieee80211_ht_capabilities *htcaps,
+		      struct ieee80211_ht_capabilities *htcaps_mask,
+		      const char *ht_mcs)
+{
+	/* parse ht_mcs into hex array */
+	int i;
+	const char* tmp = ht_mcs;
+	char* end = NULL;
+
+	/* This is what we are setting in the kernel.. */
+	os_memset(&htcaps->supported_mcs_set, 0, IEEE80211_HT_MCS_MASK_LEN);
+
+	wpa_msg(wpa_s, MSG_ERROR, "set_htcap, ht_mcs -:%s:-\n", ht_mcs);
+
+	for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
+		errno = 0;
+		long v = strtol(tmp, &end, 16);
+		if (errno == 0) {
+			wpa_msg(wpa_s, MSG_ERROR, "htcap value[%i]: %ld end: %p  tmp: %p\n",
+				i, v, end, tmp);
+			if (end == tmp) {
+				break;
+			}
+
+			htcaps->supported_mcs_set[i] = v;
+			tmp = end;
+		}
+		else {
+			wpa_msg(wpa_s, MSG_ERROR,
+				"Failed to parse ht-mcs: %s, error: %s\n",
+				ht_mcs, strerror(errno));
+			return -1;
+		}
+	}
+
+	if (i) {
+		os_memset(&htcaps_mask->supported_mcs_set, 0xff, IEEE80211_HT_MCS_MASK_LEN-1);
+		htcaps_mask->supported_mcs_set[IEEE80211_HT_MCS_MASK_LEN-1] = 0x1f; /* skip the 3 reserved bits */
+	}
+
+	return 0;
+}
+
+
+int wpa_disable_max_amsdu(struct wpa_supplicant *wpa_s,
+			  struct ieee80211_ht_capabilities *htcaps,
+			  struct ieee80211_ht_capabilities *htcaps_mask,
+			  int disabled)
+{
+	wpa_msg(wpa_s, MSG_DEBUG, "wpa: set_disable_max_amsdu: %d\n",
+		disabled);
+
+	if (disabled == -1)
+		return 0;
+
+	u16 msk = host_to_le16(HT_CAP_INFO_MAX_AMSDU_SIZE);
+	htcaps_mask->ht_capabilities_info |= msk;
+	if (disabled)
+		htcaps->ht_capabilities_info &= msk;
+	else
+		htcaps->ht_capabilities_info |= msk;
+	return 0;
+}
+
+int wpa_set_ampdu_factor(struct wpa_supplicant *wpa_s,
+			 struct ieee80211_ht_capabilities *htcaps,
+			 struct ieee80211_ht_capabilities *htcaps_mask,
+			 int factor)
+{
+	wpa_msg(wpa_s, MSG_DEBUG, "wpa: set_ampdu_factor: %d\n",
+		factor);
+
+	if (factor == -1)
+		return 0;
+
+	if (factor < 0 || factor > 3) {
+		wpa_msg(wpa_s, MSG_ERROR,
+			"wpa: ampdu_factor: %d out of range.  Must be 0-3 or -1\n",
+			factor);
+		return -EINVAL;
+	}
+
+	htcaps_mask->a_mpdu_params |= 0x3; // 2 bits for factor
+	htcaps->a_mpdu_params &= ~0x3;
+	htcaps->a_mpdu_params |= factor & 0x3;
+	return 0;
+}
+
+int wpa_set_ampdu_density(struct wpa_supplicant *wpa_s,
+			  struct ieee80211_ht_capabilities *htcaps,
+			  struct ieee80211_ht_capabilities *htcaps_mask,
+			  int density)
+{
+	wpa_msg(wpa_s, MSG_DEBUG, "wpa: set_ampdu_density: %d\n",
+		density);
+
+	if (density == -1)
+		return 0;
+
+	if (density < 0 || density > 7) {
+		wpa_msg(wpa_s, MSG_ERROR,
+			"wpa: ampdu_density: %d out of range.  Must be 0-7 or -1.\n",
+			density);
+		return -EINVAL;
+	}
+
+	htcaps_mask->a_mpdu_params |= 0x1C;
+	htcaps->a_mpdu_params &= ~(0x1C);
+	htcaps->a_mpdu_params |= (density << 2) & 0x1C;
+	return 0;
+}
+
+int wpa_set_disable_ht40(struct wpa_supplicant *wpa_s,
+			 struct ieee80211_ht_capabilities *htcaps,
+			 struct ieee80211_ht_capabilities *htcaps_mask,
+			 int disabled)
+{
+	/* Masking these out disables HT-40 */
+	u16 msk = host_to_le16(HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET |
+			       HT_CAP_INFO_SHORT_GI40MHZ);
+
+	wpa_msg(wpa_s, MSG_DEBUG, "wpa: set_disable_ht40: %d\n",
+		disabled);
+
+	if (disabled)
+		htcaps->ht_capabilities_info &= ~msk;
+	else
+		htcaps->ht_capabilities_info |= msk;
+
+	htcaps_mask->ht_capabilities_info |= msk;
+	return 0;
+}
+#endif
+
+
+void wpa_supplicant_apply_ht_overrides(struct wpa_supplicant *wpa_s,
+				       struct wpa_driver_associate_params *params)
+{
+#ifdef CONFIG_HT_OVERRIDES
+	struct wpa_ssid *ssid = wpa_s->current_ssid;
+	if (ssid) {
+		params->disable_ht = ssid->disable_ht;
+
+		wpa_set_htcap_mcs(wpa_s, &params->htcaps, &params->htcaps_mask, ssid->ht_mcs);
+		wpa_disable_max_amsdu(wpa_s, &params->htcaps, &params->htcaps_mask,
+				      ssid->disable_max_amsdu);
+		wpa_set_ampdu_factor(wpa_s, &params->htcaps, &params->htcaps_mask,
+				     ssid->ampdu_factor);
+		wpa_set_ampdu_density(wpa_s, &params->htcaps, &params->htcaps_mask,
+				      ssid->ampdu_density);
+		wpa_set_disable_ht40(wpa_s, &params->htcaps, &params->htcaps_mask,
+				     ssid->disable_ht40);
+	}
+#endif
+}
 
 static int wpa_supplicant_init_iface(struct wpa_supplicant *wpa_s,
 				     struct wpa_interface *iface)
diff --git a/wpa_supplicant/wpa_supplicant_i.h b/wpa_supplicant/wpa_supplicant_i.h
index 59fc9a3..6d4643d 100644
--- a/wpa_supplicant/wpa_supplicant_i.h
+++ b/wpa_supplicant/wpa_supplicant_i.h
@@ -36,6 +36,8 @@ struct scan_info;
 struct wpa_bss;
 struct wpa_scan_results;
 struct hostapd_hw_modes;
+struct ieee80211_ht_capabilities;
+struct wpa_driver_associate_params;
 
 /*
  * Forward declarations of private structures used within the ctrl_iface
@@ -514,6 +516,31 @@ struct wpa_supplicant {
 
 
 /* wpa_supplicant.c */
+#ifdef CONFIG_HT_OVERRIDES
+int wpa_set_htcap_mcs(struct wpa_supplicant *wpa_s,
+		      struct ieee80211_ht_capabilities *htcaps,
+		      struct ieee80211_ht_capabilities *htcaps_mask,
+		      const char *ht_mcs);
+int wpa_disable_max_amsdu(struct wpa_supplicant *wpa_s,
+			  struct ieee80211_ht_capabilities *htcaps,
+			  struct ieee80211_ht_capabilities *htcaps_mask,
+			  int disabled);
+int wpa_set_ampdu_factor(struct wpa_supplicant *wpa_s,
+			 struct ieee80211_ht_capabilities *htcaps,
+			 struct ieee80211_ht_capabilities *htcaps_mask,
+			 int factor);
+int wpa_set_ampdu_density(struct wpa_supplicant *wpa_s,
+			  struct ieee80211_ht_capabilities *htcaps,
+			  struct ieee80211_ht_capabilities *htcaps_mask,
+			  int density);
+int wpa_set_disable_ht40(struct wpa_supplicant *wpa_s,
+			 struct ieee80211_ht_capabilities *htcaps,
+			 struct ieee80211_ht_capabilities *htcaps_mask,
+			 int disabled);
+#endif
+void wpa_supplicant_apply_ht_overrides(struct wpa_supplicant *wpa_s,
+			struct wpa_driver_associate_params *params);
+
 int wpa_set_wep_keys(struct wpa_supplicant *wpa_s, struct wpa_ssid *ssid);
 
 int wpa_supplicant_reload_configuration(struct wpa_supplicant *wpa_s);
-- 
1.7.3.4



More information about the HostAP mailing list