Commit dc1e3cb8 authored by John Crispin's avatar John Crispin Committed by Johannes Berg
Browse files

nl80211: MBSSID and EMA support in AP mode 



Add new attributes to configure support for multiple BSSID
and advanced multi-BSSID advertisements (EMA) in AP mode.

- NL80211_ATTR_MBSSID_CONFIG used for per interface configuration.
- NL80211_ATTR_MBSSID_ELEMS used to MBSSID elements for beacons.

Memory for the elements is allocated dynamically. This change frees
the memory in existing functions which call nl80211_parse_beacon(),
a comment is added to indicate the new references to do the same.

Signed-off-by: default avatarJohn Crispin <john@phrozen.org>
Co-developed-by: default avatarAloka Dixit <alokad@codeaurora.org>
Signed-off-by: default avatarAloka Dixit <alokad@codeaurora.org>
Link: https://lore.kernel.org/r/20210916025437.29138-2-alokad@codeaurora.org


[don't leave ERR_PTR hanging around]
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 05075fe7

include/net/cfg80211.h

+44 −0
Original line number Diff line number Diff line
@@ -1056,6 +1056,36 @@ struct cfg80211_crypto_settings { 
	enum nl80211_sae_pwe_mechanism sae_pwe;

};



/**

 * struct cfg80211_mbssid_config - AP settings for multi bssid

 *

 * @tx_wdev: pointer to the transmitted interface in the MBSSID set

 * @index: index of this AP in the multi bssid group.

 * @ema: set to true if the beacons should be sent out in EMA mode.

 */

struct cfg80211_mbssid_config {

	struct wireless_dev *tx_wdev;

	u8 index;

	bool ema;

};



/**

 * struct cfg80211_mbssid_elems - Multiple BSSID elements

 *

 * @cnt: Number of elements in array %elems.

 *

 * @elem: Array of multiple BSSID element(s) to be added into Beacon frames.

 * @elem.data: Data for multiple BSSID elements.

 * @elem.len: Length of data.

 */

struct cfg80211_mbssid_elems {

	u8 cnt;

	struct {

		const u8 *data;

		size_t len;

	} elem[];

};



/**

 * struct cfg80211_beacon_data - beacon data

 * @head: head portion of beacon (before TIM IE)
@@ -1074,6 +1104,7 @@ struct cfg80211_crypto_settings { 
 * @assocresp_ies_len: length of assocresp_ies in octets

 * @probe_resp_len: length of probe response template (@probe_resp)

 * @probe_resp: probe response template (AP mode only)

 * @mbssid_ies: multiple BSSID elements

 * @ftm_responder: enable FTM responder functionality; -1 for no change

 *	(which also implies no change in LCI/civic location data)

 * @lci: Measurement Report element content, starting with Measurement Token
@@ -1091,6 +1122,7 @@ struct cfg80211_beacon_data { 
	const u8 *probe_resp;

	const u8 *lci;

	const u8 *civicloc;

	struct cfg80211_mbssid_elems *mbssid_ies;

	s8 ftm_responder;



	size_t head_len, tail_len;
@@ -1205,6 +1237,7 @@ enum cfg80211_ap_settings_flags { 
 * @he_oper: HE operation IE (or %NULL if HE isn't enabled)

 * @fils_discovery: FILS discovery transmission parameters

 * @unsol_bcast_probe_resp: Unsolicited broadcast probe response parameters

 * @mbssid_config: AP settings for multiple bssid

 */

struct cfg80211_ap_settings {

	struct cfg80211_chan_def chandef;
@@ -1237,6 +1270,7 @@ struct cfg80211_ap_settings { 
	struct cfg80211_he_bss_color he_bss_color;

	struct cfg80211_fils_discovery fils_discovery;

	struct cfg80211_unsol_bcast_probe_resp unsol_bcast_probe_resp;

	struct cfg80211_mbssid_config mbssid_config;

};



/**
@@ -5003,6 +5037,13 @@ struct wiphy_iftype_akm_suites { 
 *	%NL80211_TID_CONFIG_ATTR_RETRY_LONG attributes

 * @sar_capa: SAR control capabilities

 * @rfkill: a pointer to the rfkill structure

 *

 * @mbssid_max_interfaces: maximum number of interfaces supported by the driver

 *	in a multiple BSSID set. This field must be set to a non-zero value

 *	by the driver to advertise MBSSID support.

 * @mbssid_max_ema_profile_periodicity: maximum profile periodicity supported by

 *	the driver. Setting this field to a non-zero value indicates that the

 *	driver supports enhanced multi-BSSID advertisements (EMA AP).

 */

struct wiphy {

	struct mutex mtx;
@@ -5147,6 +5188,9 @@ struct wiphy { 


	struct rfkill *rfkill;



	u8 mbssid_max_interfaces;

	u8 ema_max_profile_periodicity;



	char priv[] __aligned(NETDEV_ALIGN);

};

include/uapi/linux/nl80211.h

+75 −1
Original line number Diff line number Diff line
@@ -360,7 +360,10 @@ 
 * @NL80211_CMD_DEL_INTERFACE: Virtual interface was deleted, has attributes

 *	%NL80211_ATTR_IFINDEX and %NL80211_ATTR_WIPHY. Can also be sent from

 *	userspace to request deletion of a virtual interface, then requires

 *	attribute %NL80211_ATTR_IFINDEX.

 *	attribute %NL80211_ATTR_IFINDEX. If multiple BSSID advertisements are

 *	enabled using %NL80211_ATTR_MBSSID_CONFIG, %NL80211_ATTR_MBSSID_ELEMS,

 *	and if this command is used for the transmitting interface, then all

 *	the non-transmitting interfaces are deleted as well.

 *

 * @NL80211_CMD_GET_KEY: Get sequence counter information for a key specified

 *	by %NL80211_ATTR_KEY_IDX and/or %NL80211_ATTR_MAC.
@@ -2624,6 +2627,18 @@ enum nl80211_commands { 
 * @NL80211_ATTR_COLOR_CHANGE_ELEMS: Nested set of attributes containing the IE

 *	information for the time while performing a color switch.

 *

 * @NL80211_ATTR_MBSSID_CONFIG: Nested attribute for multiple BSSID

 *	advertisements (MBSSID) parameters in AP mode.

 *	Kernel uses this attribute to indicate the driver's support for MBSSID

 *	and enhanced multi-BSSID advertisements (EMA AP) to the userspace.

 *	Userspace should use this attribute to configure per interface MBSSID

 *	parameters.

 *	See &enum nl80211_mbssid_config_attributes for details.

 *

 * @NL80211_ATTR_MBSSID_ELEMS: Nested parameter to pass multiple BSSID elements.

 *	Mandatory parameter for the transmitting interface to enable MBSSID.

 *	Optional for the non-transmitting interfaces.

 *

 * @NUM_NL80211_ATTR: total number of nl80211_attrs available

 * @NL80211_ATTR_MAX: highest attribute number currently defined

 * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3127,6 +3142,9 @@ enum nl80211_attrs { 
	NL80211_ATTR_COLOR_CHANGE_COLOR,

	NL80211_ATTR_COLOR_CHANGE_ELEMS,



	NL80211_ATTR_MBSSID_CONFIG,

	NL80211_ATTR_MBSSID_ELEMS,



	/* add attributes here, update the policy in nl80211.c */



	__NL80211_ATTR_AFTER_LAST,
@@ -7386,4 +7404,60 @@ enum nl80211_sar_specs_attrs { 
	NL80211_SAR_ATTR_SPECS_MAX = __NL80211_SAR_ATTR_SPECS_LAST - 1,

};



/**

 * enum nl80211_mbssid_config_attributes - multiple BSSID (MBSSID) and enhanced

 * multi-BSSID advertisements (EMA) in AP mode.

 * Kernel uses some of these attributes to advertise driver's support for

 * MBSSID and EMA.

 * Remaining attributes should be used by the userspace to configure the

 * features.

 *

 * @__NL80211_MBSSID_CONFIG_ATTR_INVALID: Invalid

 *

 * @NL80211_MBSSID_CONFIG_ATTR_MAX_INTERFACES: Used by the kernel to advertise

 *	the maximum number of MBSSID interfaces supported by the driver.

 *	Driver should indicate MBSSID support by setting

 *	wiphy->mbssid_max_interfaces to a value more than or equal to 2.

 *

 * @NL80211_MBSSID_CONFIG_ATTR_MAX_EMA_PROFILE_PERIODICITY: Used by the kernel

 *	to advertise the maximum profile periodicity supported by the driver

 *	if EMA is enabled. Driver should indicate EMA support to the userspace

 *	by setting wiphy->mbssid_max_ema_profile_periodicity to

 *	a non-zero value.

 *

 * @NL80211_MBSSID_CONFIG_ATTR_INDEX: Mandatory parameter to pass the index of

 *	this BSS (u8) in the multiple BSSID set.

 *	Value must be set to 0 for the transmitting interface and non-zero for

 *	all non-transmitting interfaces. The userspace will be responsible

 *	for using unique indices for the interfaces.

 *	Range: 0 to wiphy->mbssid_max_interfaces-1.

 *

 * @NL80211_MBSSID_CONFIG_ATTR_TX_IFINDEX: Mandatory parameter for

 *	a non-transmitted profile which provides the interface index (u32) of

 *	the transmitted profile. The value must match one of the interface

 *	indices advertised by the kernel. Optional if the interface being set up

 *	is the transmitting one, however, if provided then the value must match

 *	the interface index of the same.

 *

 * @NL80211_MBSSID_CONFIG_ATTR_EMA: Flag used to enable EMA AP feature.

 *	Setting this flag is permitted only if the driver advertises EMA support

 *	by setting wiphy->mbssid_max_ema_profile_periodicity to non-zero.

 *

 * @__NL80211_MBSSID_CONFIG_ATTR_LAST: Internal

 * @NL80211_MBSSID_CONFIG_ATTR_MAX: highest attribute

 */

enum nl80211_mbssid_config_attributes {

	__NL80211_MBSSID_CONFIG_ATTR_INVALID,



	NL80211_MBSSID_CONFIG_ATTR_MAX_INTERFACES,

	NL80211_MBSSID_CONFIG_ATTR_MAX_EMA_PROFILE_PERIODICITY,

	NL80211_MBSSID_CONFIG_ATTR_INDEX,

	NL80211_MBSSID_CONFIG_ATTR_TX_IFINDEX,

	NL80211_MBSSID_CONFIG_ATTR_EMA,



	/* keep last */

	__NL80211_MBSSID_CONFIG_ATTR_LAST,

	NL80211_MBSSID_CONFIG_ATTR_MAX = __NL80211_MBSSID_CONFIG_ATTR_LAST - 1,

};



#endif /* __LINUX_NL80211_H */

net/wireless/nl80211.c

+174 −4
Original line number Diff line number Diff line
@@ -437,6 +437,16 @@ sar_policy[NL80211_SAR_ATTR_MAX + 1] = { 
	[NL80211_SAR_ATTR_SPECS] = NLA_POLICY_NESTED_ARRAY(sar_specs_policy),

};



static const struct nla_policy

nl80211_mbssid_config_policy[NL80211_MBSSID_CONFIG_ATTR_MAX + 1] = {

	[NL80211_MBSSID_CONFIG_ATTR_MAX_INTERFACES] = NLA_POLICY_MIN(NLA_U8, 2),

	[NL80211_MBSSID_CONFIG_ATTR_MAX_EMA_PROFILE_PERIODICITY] =

						NLA_POLICY_MIN(NLA_U8, 1),

	[NL80211_MBSSID_CONFIG_ATTR_INDEX] = { .type = NLA_U8 },

	[NL80211_MBSSID_CONFIG_ATTR_TX_IFINDEX] = { .type = NLA_U32 },

	[NL80211_MBSSID_CONFIG_ATTR_EMA] = { .type = NLA_FLAG },

};



static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {

	[0] = { .strict_start_type = NL80211_ATTR_HE_OBSS_PD },

	[NL80211_ATTR_WIPHY] = { .type = NLA_U32 },
@@ -763,6 +773,9 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = { 
	[NL80211_ATTR_COLOR_CHANGE_COUNT] = { .type = NLA_U8 },

	[NL80211_ATTR_COLOR_CHANGE_COLOR] = { .type = NLA_U8 },

	[NL80211_ATTR_COLOR_CHANGE_ELEMS] = NLA_POLICY_NESTED(nl80211_policy),

	[NL80211_ATTR_MBSSID_CONFIG] =

			NLA_POLICY_NESTED(nl80211_mbssid_config_policy),

	[NL80211_ATTR_MBSSID_ELEMS] = { .type = NLA_NESTED },

};



/* policy for the key attributes */
@@ -2207,6 +2220,35 @@ nl80211_put_sar_specs(struct cfg80211_registered_device *rdev, 
	return -ENOBUFS;

}



static int nl80211_put_mbssid_support(struct wiphy *wiphy, struct sk_buff *msg)

{

	struct nlattr *config;



	if (!wiphy->mbssid_max_interfaces)

		return 0;



	config = nla_nest_start(msg, NL80211_ATTR_MBSSID_CONFIG);

	if (!config)

		return -ENOBUFS;



	if (nla_put_u8(msg, NL80211_MBSSID_CONFIG_ATTR_MAX_INTERFACES,

		       wiphy->mbssid_max_interfaces))

		goto fail;



	if (wiphy->ema_max_profile_periodicity &&

	    nla_put_u8(msg,

		       NL80211_MBSSID_CONFIG_ATTR_MAX_EMA_PROFILE_PERIODICITY,

		       wiphy->ema_max_profile_periodicity))

		goto fail;



	nla_nest_end(msg, config);

	return 0;



fail:

	nla_nest_cancel(msg, config);

	return -ENOBUFS;

}



struct nl80211_dump_wiphy_state {

	s64 filter_wiphy;

	long start;
@@ -2792,6 +2834,9 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev, 
		if (nl80211_put_sar_specs(rdev, msg))

			goto nla_put_failure;



		if (nl80211_put_mbssid_support(&rdev->wiphy, msg))

			goto nla_put_failure;



		/* done */

		state->split_start = 0;

		break;
@@ -4981,6 +5026,96 @@ static int validate_beacon_tx_rate(struct cfg80211_registered_device *rdev, 
	return 0;

}



static int nl80211_parse_mbssid_config(struct wiphy *wiphy,

				       struct net_device *dev,

				       struct nlattr *attrs,

				       struct cfg80211_mbssid_config *config,

				       u8 num_elems)

{

	struct nlattr *tb[NL80211_MBSSID_CONFIG_ATTR_MAX + 1];



	if (!wiphy->mbssid_max_interfaces)

		return -EOPNOTSUPP;



	if (nla_parse_nested(tb, NL80211_MBSSID_CONFIG_ATTR_MAX, attrs, NULL,

			     NULL) ||

	    !tb[NL80211_MBSSID_CONFIG_ATTR_INDEX])

		return -EINVAL;



	config->ema = nla_get_flag(tb[NL80211_MBSSID_CONFIG_ATTR_EMA]);

	if (config->ema) {

		if (!wiphy->ema_max_profile_periodicity)

			return -EOPNOTSUPP;



		if (num_elems > wiphy->ema_max_profile_periodicity)

			return -EINVAL;

	}



	config->index = nla_get_u8(tb[NL80211_MBSSID_CONFIG_ATTR_INDEX]);

	if (config->index >= wiphy->mbssid_max_interfaces ||

	    (!config->index && !num_elems))

		return -EINVAL;



	if (tb[NL80211_MBSSID_CONFIG_ATTR_TX_IFINDEX]) {

		u32 tx_ifindex =

			nla_get_u32(tb[NL80211_MBSSID_CONFIG_ATTR_TX_IFINDEX]);



		if ((!config->index && tx_ifindex != dev->ifindex) ||

		    (config->index && tx_ifindex == dev->ifindex))

			return -EINVAL;



		if (tx_ifindex != dev->ifindex) {

			struct net_device *tx_netdev =

				dev_get_by_index(wiphy_net(wiphy), tx_ifindex);



			if (!tx_netdev || !tx_netdev->ieee80211_ptr ||

			    tx_netdev->ieee80211_ptr->wiphy != wiphy ||

			    tx_netdev->ieee80211_ptr->iftype !=

							NL80211_IFTYPE_AP) {

				dev_put(tx_netdev);

				return -EINVAL;

			}



			config->tx_wdev = tx_netdev->ieee80211_ptr;

		} else {

			config->tx_wdev = dev->ieee80211_ptr;

		}

	} else if (!config->index) {

		config->tx_wdev = dev->ieee80211_ptr;

	} else {

		return -EINVAL;

	}



	return 0;

}



static struct cfg80211_mbssid_elems *

nl80211_parse_mbssid_elems(struct wiphy *wiphy, struct nlattr *attrs)

{

	struct nlattr *nl_elems;

	struct cfg80211_mbssid_elems *elems;

	int rem_elems;

	u8 i = 0, num_elems = 0;



	if (!wiphy->mbssid_max_interfaces)

		return ERR_PTR(-EINVAL);



	nla_for_each_nested(nl_elems, attrs, rem_elems)

		num_elems++;



	elems = kzalloc(struct_size(elems, elem, num_elems), GFP_KERNEL);

	if (!elems)

		return ERR_PTR(-ENOMEM);



	nla_for_each_nested(nl_elems, attrs, rem_elems) {

		elems->elem[i].data = nla_data(nl_elems);

		elems->elem[i].len = nla_len(nl_elems);

		i++;

	}

	elems->cnt = num_elems;

	return elems;

}



static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev,

				struct nlattr *attrs[],

				struct cfg80211_beacon_data *bcn)
@@ -5061,6 +5196,17 @@ static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev, 
		bcn->ftm_responder = -1;

	}



	if (attrs[NL80211_ATTR_MBSSID_ELEMS]) {

		struct cfg80211_mbssid_elems *mbssid =

			nl80211_parse_mbssid_elems(&rdev->wiphy,

						   attrs[NL80211_ATTR_MBSSID_ELEMS]);



		if (IS_ERR(mbssid))

			return PTR_ERR(mbssid);



		bcn->mbssid_ies = mbssid;

	}



	return 0;

}
@@ -5547,6 +5693,17 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info) 
			goto out;

	}



	if (info->attrs[NL80211_ATTR_MBSSID_CONFIG]) {

		err = nl80211_parse_mbssid_config(&rdev->wiphy, dev,

						  info->attrs[NL80211_ATTR_MBSSID_CONFIG],

						  &params->mbssid_config,

						  params->beacon.mbssid_ies ?

							params->beacon.mbssid_ies->cnt :

							0);

		if (err)

			goto out;

	}



	nl80211_calculate_ap_params(params);



	if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])
@@ -5568,6 +5725,11 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info) 


out:

	kfree(params->acl);

	kfree(params->beacon.mbssid_ies);

	if (params->mbssid_config.tx_wdev &&

	    params->mbssid_config.tx_wdev->netdev &&

	    params->mbssid_config.tx_wdev->netdev != dev)

		dev_put(params->mbssid_config.tx_wdev->netdev);

	kfree(params);



	return err;
@@ -5593,12 +5755,14 @@ static int nl80211_set_beacon(struct sk_buff *skb, struct genl_info *info) 


	err = nl80211_parse_beacon(rdev, info->attrs, &params);

	if (err)

		return err;

		goto out;



	wdev_lock(wdev);

	err = rdev_change_beacon(rdev, dev, &params);

	wdev_unlock(wdev);



out:

	kfree(params.mbssid_ies);

	return err;

}
@@ -9275,12 +9439,14 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info) 


	err = nl80211_parse_beacon(rdev, info->attrs, &params.beacon_after);

	if (err)

		return err;

		goto free;



	csa_attrs = kcalloc(NL80211_ATTR_MAX + 1, sizeof(*csa_attrs),

			    GFP_KERNEL);

	if (!csa_attrs)

		return -ENOMEM;

	if (!csa_attrs) {

		err = -ENOMEM;

		goto free;

	}



	err = nla_parse_nested_deprecated(csa_attrs, NL80211_ATTR_MAX,

					  info->attrs[NL80211_ATTR_CSA_IES],
@@ -9398,6 +9564,8 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info) 
	wdev_unlock(wdev);



free:

	kfree(params.beacon_after.mbssid_ies);

	kfree(params.beacon_csa.mbssid_ies);

	kfree(csa_attrs);

	return err;

}
@@ -14933,6 +15101,8 @@ static int nl80211_color_change(struct sk_buff *skb, struct genl_info *info) 
	wdev_unlock(wdev);



out:

	kfree(params.beacon_next.mbssid_ies);

	kfree(params.beacon_color_change.mbssid_ies);

	kfree(tb);

	return err;

}