[PATCH v4] hostap: Support ht-cap over-rides.

greearb at candelatech.com greearb
Thu Jan 5 10:53:03 PST 2012


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>
---

v4:  I believe this addresses all concerns raised in the review
of v3.  Rebased against yesterday's top-of-tree as well.

:100644 100644 66801fd... b7e0af7... M	src/common/ieee802_11_defs.h
:100644 100644 d72c83b... 03917e3... M	src/drivers/driver.h
:100644 100644 6af8cc9... c8a4323... M	src/drivers/driver_nl80211.c
:100644 100644 f9261c2... a8028dd... M	src/drivers/nl80211_copy.h
:100644 100644 0832f10... 151d879... M	wpa_supplicant/Makefile
:100644 100644 0fd1f3e... 6858b28... M	wpa_supplicant/config.c
:100644 100644 f9e5043... 4db78e3... M	wpa_supplicant/config.h
:100644 100644 8a47c0b... fb3b8a7... M	wpa_supplicant/config_ssid.h
:100644 100644 cff25d6... 89bb458... M	wpa_supplicant/defconfig
:100644 100644 c5e47d1... 53ed03e... M	wpa_supplicant/sme.c
:100644 100644 68b80b9... 6f2ee5d... M	wpa_supplicant/wpa_supplicant.c
:100644 100644 3e3b23d... 139426e... M	wpa_supplicant/wpa_supplicant_i.h
 src/common/ieee802_11_defs.h      |    1 +
 src/drivers/driver.h              |   13 +++
 src/drivers/driver_nl80211.c      |   18 ++++
 src/drivers/nl80211_copy.h        |    5 +
 wpa_supplicant/Makefile           |    4 +
 wpa_supplicant/config.c           |   18 ++++
 wpa_supplicant/config.h           |    5 +
 wpa_supplicant/config_ssid.h      |   49 ++++++++++
 wpa_supplicant/defconfig          |    3 +
 wpa_supplicant/sme.c              |   11 +++
 wpa_supplicant/wpa_supplicant.c   |  178 +++++++++++++++++++++++++++++++++++++
 wpa_supplicant/wpa_supplicant_i.h |    4 +
 12 files changed, 309 insertions(+), 0 deletions(-)

diff --git a/src/common/ieee802_11_defs.h b/src/common/ieee802_11_defs.h
index 66801fd..b7e0af7 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 d72c83b..03917e3 100644
--- a/src/drivers/driver.h
+++ b/src/drivers/driver.h
@@ -516,6 +516,19 @@ struct wpa_driver_associate_params {
 	 * STA mode: bits 0..3 UAPSD enabled for VO,VI,BK,BE
 	 */
 	int uapsd;
+
+	/**
+	 * 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.
+	 */
+	u8* htcaps;       /* struct ieee80211_ht_capabilities* */
+	u8* htcaps_mask;  /* struct ieee80211_ht_capabilities* */
 };
 
 enum hide_ssid {
diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
index 6af8cc9..c8a4323 100644
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -6618,6 +6618,15 @@ skip_auth_type:
 		NLA_PUT_U32(msg, NL80211_ATTR_AKM_SUITES, mgmt);
 	}
 
+	if (params->disable_ht)
+		NLA_PUT_FLAG(msg, NL80211_ATTR_DISABLE_HT);
+
+	if (params->htcaps && params->htcaps_mask) {
+		int sz = sizeof(struct ieee80211_ht_capabilities);
+		NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY, sz, params->htcaps);
+		NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY_MASK, sz, params->htcaps_mask);
+	}
+
 	ret = nl80211_set_conn_keys(params, msg);
 	if (ret)
 		goto nla_put_failure;
@@ -6765,6 +6774,15 @@ static int wpa_driver_nl80211_associate(
 			params->prev_bssid);
 	}
 
+	if (params->disable_ht)
+		NLA_PUT_FLAG(msg, NL80211_ATTR_DISABLE_HT);
+
+	if (params->htcaps && params->htcaps_mask) {
+		int sz = sizeof(struct ieee80211_ht_capabilities);
+		NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY, sz, params->htcaps);
+		NLA_PUT(msg, NL80211_ATTR_HT_CAPABILITY_MASK, sz, params->htcaps_mask);
+	}
+
 	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 0832f10..151d879 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 0fd1f3e..6858b28 100644
--- a/wpa_supplicant/config.c
+++ b/wpa_supplicant/config.c
@@ -1598,6 +1598,14 @@ static const struct parse_data ssid_fields[] = {
 #ifdef CONFIG_P2P
 	{ FUNC(p2p_client_list) },
 #endif /* CONFIG_P2P */
+#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
@@ -1765,6 +1773,9 @@ void wpa_config_free_ssid(struct wpa_ssid *ssid)
 	os_free(ssid->freq_list);
 	os_free(ssid->bgscan);
 	os_free(ssid->p2p_client_list);
+#ifdef CONFIG_HT_OVERRIDES
+	os_free(ssid->ht_mcs);
+#endif
 	os_free(ssid);
 }
 
@@ -1952,6 +1963,13 @@ 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;
+#endif
 }
 
 
diff --git a/wpa_supplicant/config.h b/wpa_supplicant/config.h
index f9e5043..4db78e3 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 8a47c0b..fb3b8a7 100644
--- a/wpa_supplicant/config_ssid.h
+++ b/wpa_supplicant/config_ssid.h
@@ -422,6 +422,55 @@ 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 cff25d6..89bb458 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 c5e47d1..53ed03e 100644
--- a/wpa_supplicant/sme.c
+++ b/wpa_supplicant/sme.c
@@ -367,8 +367,18 @@ void sme_associate(struct wpa_supplicant *wpa_s, enum wpas_mode mode,
 {
 	struct wpa_driver_associate_params params;
 	struct ieee802_11_elems elems;
+#ifdef CONFIG_HT_OVERRIDES
+	struct ieee80211_ht_capabilities htcaps;
+	struct ieee80211_ht_capabilities htcaps_mask;
+	os_memset(&htcaps, 0, sizeof(htcaps));
+	os_memset(&htcaps_mask, 0, sizeof(htcaps_mask));
+#endif
 
 	os_memset(&params, 0, sizeof(params));
+#ifdef CONFIG_HT_OVERRIDES
+	params.htcaps = (u8*)(&htcaps);
+	params.htcaps_mask = (u8*)(&htcaps_mask);
+#endif
 	params.bssid = bssid;
 	params.ssid = wpa_s->sme.ssid;
 	params.ssid_len = wpa_s->sme.ssid_len;
@@ -378,6 +388,7 @@ 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 68b80b9..6f2ee5d 100644
--- a/wpa_supplicant/wpa_supplicant.c
+++ b/wpa_supplicant/wpa_supplicant.c
@@ -1122,6 +1122,13 @@ void wpa_supplicant_associate(struct wpa_supplicant *wpa_s,
 	int assoc_failed = 0;
 	struct wpa_ssid *old_ssid;
 
+#ifdef CONFIG_HT_OVERRIDES
+	struct ieee80211_ht_capabilities htcaps;
+	struct ieee80211_ht_capabilities htcaps_mask;
+	os_memset(&htcaps, 0, sizeof(htcaps));
+	os_memset(&htcaps_mask, 0, sizeof(htcaps_mask));
+#endif
+
 #ifdef CONFIG_IBSS_RSN
 	ibss_rsn_deinit(wpa_s->ibss_rsn);
 	wpa_s->ibss_rsn = NULL;
@@ -1157,6 +1164,10 @@ void wpa_supplicant_associate(struct wpa_supplicant *wpa_s,
 	}
 
 	os_memset(&params, 0, sizeof(params));
+#ifdef CONFIG_HT_OVERRIDES
+	params.htcaps = (u8*)(&htcaps);
+	params.htcaps_mask = (u8*)(&htcaps_mask);
+#endif
 	wpa_s->reassociate = 0;
 	if (bss && !wpas_driver_bss_selection(wpa_s)) {
 #ifdef CONFIG_IEEE80211R
@@ -1415,6 +1426,8 @@ 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 "
@@ -2166,6 +2179,171 @@ static struct wpa_supplicant * wpa_supplicant_alloc(void)
 	return wpa_s;
 }
 
+#ifdef CONFIG_HT_OVERRIDES
+static 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;
+
+	/* If ht_mcs is null, do not set anything */
+	if (!ht_mcs)
+		return 0;
+	
+	/* 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 we were able to parse any values, then set mask for the MCS set. */
+	if (i) {
+		os_memset(&htcaps_mask->supported_mcs_set, 0xff, IEEE80211_HT_MCS_MASK_LEN-1);
+		/* skip the 3 reserved bits */
+		htcaps_mask->supported_mcs_set[IEEE80211_HT_MCS_MASK_LEN-1] = 0x1f;
+	}
+
+	return 0;
+}
+
+
+static 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;
+}
+
+static 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;
+}
+
+static 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;
+}
+
+static 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;
+		if (params->htcaps && params->htcaps_mask) {
+			struct ieee80211_ht_capabilities* htcaps;
+			struct ieee80211_ht_capabilities* htcaps_mask;
+			htcaps = (struct ieee80211_ht_capabilities*)(params->htcaps);
+			htcaps_mask = (struct ieee80211_ht_capabilities*)(params->htcaps_mask);
+
+			wpa_set_htcap_mcs(wpa_s, htcaps, htcaps_mask, ssid->ht_mcs);
+			wpa_disable_max_amsdu(wpa_s, htcaps, htcaps_mask, ssid->disable_max_amsdu);
+			wpa_set_ampdu_factor(wpa_s, htcaps, htcaps_mask, ssid->ampdu_factor);
+			wpa_set_ampdu_density(wpa_s, htcaps, htcaps_mask, ssid->ampdu_density);
+			wpa_set_disable_ht40(wpa_s, htcaps, 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 3e3b23d..139426e 100644
--- a/wpa_supplicant/wpa_supplicant_i.h
+++ b/wpa_supplicant/wpa_supplicant_i.h
@@ -36,6 +36,7 @@ struct scan_info;
 struct wpa_bss;
 struct wpa_scan_results;
 struct hostapd_hw_modes;
+struct wpa_driver_associate_params;
 
 /*
  * Forward declarations of private structures used within the ctrl_iface
@@ -525,6 +526,9 @@ struct wpa_supplicant {
 
 
 /* wpa_supplicant.c */
+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




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