2020-08-12 15:02:33

by John Crispin

[permalink] [raw]
Subject: [PATCH V3 1/9] nl80211: add basic multiple bssid support

This patch adds support for passing the multiple bssid config to the
kernel when adding an interface. If the BSS is non-transmitting it needs
to be indicated. A non-transmitting BSSID will have a parent interface,
which needs to be transmitting. The multiple bssid elements are passed
as an array.

Signed-off-by: John Crispin <[email protected]>
---
include/net/cfg80211.h | 35 +++++++++++++++++++++++++++++++
include/uapi/linux/nl80211.h | 22 ++++++++++++++++++++
net/wireless/nl80211.c | 40 ++++++++++++++++++++++++++++++++++++
3 files changed, 97 insertions(+)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 541dea0fd571..0b0c730dc8d2 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -470,6 +470,21 @@ struct ieee80211_supported_band {
const struct ieee80211_sband_iftype_data *iftype_data;
};

+/**
+ * struct ieee80211_multiple_bssid - AP settings for multi bssid
+ *
+ * @index: the index of this AP in the multi bssid group.
+ * @count: the total number of multi bssid peer APs.
+ * @parent: a non-transmitted bssid has a transmitted parent
+ * @non_transmitted: Is this a non-transmitted bssid
+ */
+struct ieee80211_multiple_bssid {
+ u8 index;
+ u8 count;
+ u32 parent;
+ bool non_transmitted;
+};
+
/**
* ieee80211_get_sband_iftype_data - return sband data for a given iftype
* @sband: the sband to search for the STA on
@@ -614,6 +629,7 @@ static inline void wiphy_read_of_freq_limits(struct wiphy *wiphy)
* belonging to that MU-MIMO groupID; %NULL if not changed
* @vht_mumimo_follow_addr: MU-MIMO follow address, used for monitoring
* MU-MIMO packets going to the specified station; %NULL if not changed
+ * @multiple_bssid: AP settings for multiple bssid
*/
struct vif_params {
u32 flags;
@@ -621,6 +637,7 @@ struct vif_params {
u8 macaddr[ETH_ALEN];
const u8 *vht_mumimo_groups;
const u8 *vht_mumimo_follow_addr;
+ struct ieee80211_multiple_bssid multiple_bssid;
};

/**
@@ -998,6 +1015,19 @@ struct cfg80211_crypto_settings {
u8 sae_pwd_len;
};

+/**
+ * struct cfg80211_multiple_bssid_data - multiple_bssid data
+ * @ies: array of extra information element(s) to add into Beacon frames for multiple
+ * bssid or %NULL
+ * @len: array of lengths of multiple_bssid.ies in octets
+ * @cnt: number of entries in multiple_bssid.ies
+ */
+struct cfg80211_multiple_bssid_data {
+ u8 *ies[NL80211_MULTIPLE_BSSID_IES_MAX];
+ size_t len[NL80211_MULTIPLE_BSSID_IES_MAX];
+ int cnt;
+};
+
/**
* struct cfg80211_beacon_data - beacon data
* @head: head portion of beacon (before TIM IE)
@@ -1024,6 +1054,7 @@ struct cfg80211_crypto_settings {
* Token (measurement type 11)
* @lci_len: LCI data length
* @civicloc_len: Civic location data length
+ * @multiple_bssid: multiple_bssid data
*/
struct cfg80211_beacon_data {
const u8 *head, *tail;
@@ -1042,6 +1073,8 @@ struct cfg80211_beacon_data {
size_t probe_resp_len;
size_t lci_len;
size_t civicloc_len;
+
+ struct cfg80211_multiple_bssid_data multiple_bssid;
};

struct mac_address {
@@ -1111,6 +1144,7 @@ enum cfg80211_ap_settings_flags {
* @he_obss_pd: OBSS Packet Detection settings
* @he_bss_color: BSS Color settings
* @he_oper: HE operation IE (or %NULL if HE isn't enabled)
+ * @multiple_bssid: AP settings for multiple bssid
*/
struct cfg80211_ap_settings {
struct cfg80211_chan_def chandef;
@@ -1141,6 +1175,7 @@ struct cfg80211_ap_settings {
u32 flags;
struct ieee80211_he_obss_pd he_obss_pd;
struct cfg80211_he_bss_color he_bss_color;
+ struct ieee80211_multiple_bssid multiple_bssid;
};

/**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index cade02a0e60e..5bc38d53c78c 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2551,6 +2551,20 @@ enum nl80211_commands {
* @NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_C_OFF_PRESP: An array of offsets (u16) to the color
* switch counters in the probe response (%NL80211_ATTR_PROBE_RESP).
*
+ * @NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING: Set the Non-Transmitted flag for this
+ * BSSIDs beacon.
+ *
+ * @NL80211_ATTR_MULTIPLE_BSSID_PARENT: If this is a Non-Transmitted BSSID, define
+ * the parent (transmitting) interface.
+ *
+ * @NL80211_ATTR_MULTIPLE_BSSID_INDEX: The index of this BSS inside the multi bssid
+ * element.
+ *
+ * @NL80211_ATTR_MULTIPLE_BSSID_COUNT: The number of BSSs inside the multi bssid element.
+ *
+ * @NL80211_ATTR_MULTIPLE_BSSID_IES: The Elements that describe our multiple BSS group.
+ * these get passed separately as the kernel might need to split them up for EMA VAP.
+ *
* @NUM_NL80211_ATTR: total number of nl80211_attrs available
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3039,6 +3053,12 @@ enum nl80211_attrs {
NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COLOR,
NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_IES,

+ NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING,
+ NL80211_ATTR_MULTIPLE_BSSID_PARENT,
+ NL80211_ATTR_MULTIPLE_BSSID_INDEX,
+ NL80211_ATTR_MULTIPLE_BSSID_COUNT,
+ NL80211_ATTR_MULTIPLE_BSSID_IES,
+
/* add attributes here, update the policy in nl80211.c */

__NL80211_ATTR_AFTER_LAST,
@@ -3102,6 +3122,8 @@ enum nl80211_attrs {

#define NL80211_CQM_TXE_MAX_INTVL 1800

+#define NL80211_MULTIPLE_BSSID_IES_MAX 8
+
/**
* enum nl80211_iftype - (virtual) interface types
*
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 2f0bae3c6572..4ba7203ad0d2 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -662,6 +662,11 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
[NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COUNT] = { .type = NLA_U8 },
[NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COLOR] = { .type = NLA_U8 },
[NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_IES] = NLA_POLICY_NESTED(nl80211_policy),
+ [NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING] = { .type = NLA_FLAG },
+ [NL80211_ATTR_MULTIPLE_BSSID_PARENT] = { .type = NLA_U32 },
+ [NL80211_ATTR_MULTIPLE_BSSID_INDEX] = { .type = NLA_U8 },
+ [NL80211_ATTR_MULTIPLE_BSSID_COUNT] = { .type = NLA_U8 },
+ [NL80211_ATTR_MULTIPLE_BSSID_IES] = { .type = NLA_NESTED },
};

/* policy for the key attributes */
@@ -3758,6 +3763,14 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
return err;
}

+ if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING])
+ params.multiple_bssid.non_transmitted =
+ nla_get_flag(info->attrs[NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING]);
+
+ if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT])
+ params.multiple_bssid.parent =
+ nla_get_u8(info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT]);
+
if (!cfg80211_iftype_allowed(&rdev->wiphy, type, params.use_4addr, 0))
return -EOPNOTSUPP;

@@ -4670,6 +4683,21 @@ static int nl80211_parse_beacon(struct cfg80211_registered_device *rdev,
bcn->ftm_responder = -1;
}

+ if (attrs[NL80211_ATTR_MULTIPLE_BSSID_IES]) {
+ struct nlattr *nl_ie;
+ int rem_ie;
+
+ nla_for_each_nested(nl_ie, attrs[NL80211_ATTR_MULTIPLE_BSSID_IES], rem_ie) {
+ if (bcn->multiple_bssid.cnt > NL80211_MULTIPLE_BSSID_IES_MAX)
+ return -EINVAL;
+ if (nla_type(nl_ie) != bcn->multiple_bssid.cnt + 1)
+ return -EINVAL;
+ bcn->multiple_bssid.ies[bcn->multiple_bssid.cnt] = nla_data(nl_ie);
+ bcn->multiple_bssid.len[bcn->multiple_bssid.cnt] = nla_len(nl_ie);
+ bcn->multiple_bssid.cnt++;
+ }
+ }
+
return 0;
}

@@ -5032,6 +5060,18 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
goto out;
}

+ if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_INDEX])
+ params.multiple_bssid.index = nla_get_u8(
+ info->attrs[NL80211_ATTR_MULTIPLE_BSSID_INDEX]);
+
+ if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_COUNT])
+ params.multiple_bssid.count = nla_get_u8(
+ info->attrs[NL80211_ATTR_MULTIPLE_BSSID_COUNT]);
+
+ if (params.multiple_bssid.non_transmitted &&
+ !info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT])
+ return -EOPNOTSUPP;
+
nl80211_calculate_ap_params(&params);

if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])
--
2.25.1


2020-08-19 02:56:17

by Aloka Dixit

[permalink] [raw]
Subject: Re: [PATCH V3 1/9] nl80211: add basic multiple bssid support

On 2020-08-12 08:00, John Crispin wrote:
> This patch adds support for passing the multiple bssid config to the
> kernel when adding an interface. If the BSS is non-transmitting it
> needs
> to be indicated. A non-transmitting BSSID will have a parent interface,
> which needs to be transmitting. The multiple bssid elements are passed
> as an array.
>
> Signed-off-by: John Crispin <[email protected]>
> ---
> include/net/cfg80211.h | 35 +++++++++++++++++++++++++++++++
> include/uapi/linux/nl80211.h | 22 ++++++++++++++++++++
> net/wireless/nl80211.c | 40 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 97 insertions(+)
>
> diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
> index 541dea0fd571..0b0c730dc8d2 100644
> --- a/include/net/cfg80211.h
> +++ b/include/net/cfg80211.h
> @@ -470,6 +470,21 @@ struct ieee80211_supported_band {
> const struct ieee80211_sband_iftype_data *iftype_data;
> };
>
> +/**
> + * struct ieee80211_multiple_bssid - AP settings for multi bssid
> + *
> + * @index: the index of this AP in the multi bssid group.
> + * @count: the total number of multi bssid peer APs.
> + * @parent: a non-transmitted bssid has a transmitted parent
> + * @non_transmitted: Is this a non-transmitted bssid
> + */
> +struct ieee80211_multiple_bssid {
> + u8 index;
> + u8 count;
> + u32 parent;
> + bool non_transmitted;
> +};
> +
> /**
> * ieee80211_get_sband_iftype_data - return sband data for a given
> iftype
> * @sband: the sband to search for the STA on
> @@ -614,6 +629,7 @@ static inline void
> wiphy_read_of_freq_limits(struct wiphy *wiphy)
> * belonging to that MU-MIMO groupID; %NULL if not changed
> * @vht_mumimo_follow_addr: MU-MIMO follow address, used for
> monitoring
> * MU-MIMO packets going to the specified station; %NULL if not
> changed
> + * @multiple_bssid: AP settings for multiple bssid
> */
> struct vif_params {
> u32 flags;
> @@ -621,6 +637,7 @@ struct vif_params {
> u8 macaddr[ETH_ALEN];
> const u8 *vht_mumimo_groups;
> const u8 *vht_mumimo_follow_addr;
> + struct ieee80211_multiple_bssid multiple_bssid;
> };
>
> /**
> @@ -998,6 +1015,19 @@ struct cfg80211_crypto_settings {
> u8 sae_pwd_len;
> };
>
> +/**
> + * struct cfg80211_multiple_bssid_data - multiple_bssid data
> + * @ies: array of extra information element(s) to add into Beacon
> frames for multiple
> + * bssid or %NULL
> + * @len: array of lengths of multiple_bssid.ies in octets
> + * @cnt: number of entries in multiple_bssid.ies
> + */
> +struct cfg80211_multiple_bssid_data {
> + u8 *ies[NL80211_MULTIPLE_BSSID_IES_MAX];
> + size_t len[NL80211_MULTIPLE_BSSID_IES_MAX];
> + int cnt;
> +};
> +
> /**
> * struct cfg80211_beacon_data - beacon data
> * @head: head portion of beacon (before TIM IE)
> @@ -1024,6 +1054,7 @@ struct cfg80211_crypto_settings {
> * Token (measurement type 11)
> * @lci_len: LCI data length
> * @civicloc_len: Civic location data length
> + * @multiple_bssid: multiple_bssid data
> */
> struct cfg80211_beacon_data {
> const u8 *head, *tail;
> @@ -1042,6 +1073,8 @@ struct cfg80211_beacon_data {
> size_t probe_resp_len;
> size_t lci_len;
> size_t civicloc_len;
> +
> + struct cfg80211_multiple_bssid_data multiple_bssid;
> };
>
> struct mac_address {
> @@ -1111,6 +1144,7 @@ enum cfg80211_ap_settings_flags {
> * @he_obss_pd: OBSS Packet Detection settings
> * @he_bss_color: BSS Color settings
> * @he_oper: HE operation IE (or %NULL if HE isn't enabled)
> + * @multiple_bssid: AP settings for multiple bssid
> */
> struct cfg80211_ap_settings {
> struct cfg80211_chan_def chandef;
> @@ -1141,6 +1175,7 @@ struct cfg80211_ap_settings {
> u32 flags;
> struct ieee80211_he_obss_pd he_obss_pd;
> struct cfg80211_he_bss_color he_bss_color;
> + struct ieee80211_multiple_bssid multiple_bssid;
> };
>
> /**
> diff --git a/include/uapi/linux/nl80211.h
> b/include/uapi/linux/nl80211.h
> index cade02a0e60e..5bc38d53c78c 100644
> --- a/include/uapi/linux/nl80211.h
> +++ b/include/uapi/linux/nl80211.h
> @@ -2551,6 +2551,20 @@ enum nl80211_commands {
> * @NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_C_OFF_PRESP: An array of
> offsets (u16) to the color
> * switch counters in the probe response (%NL80211_ATTR_PROBE_RESP).
> *
> + * @NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING: Set the
> Non-Transmitted flag for this
> + * BSSIDs beacon.
> + *
> + * @NL80211_ATTR_MULTIPLE_BSSID_PARENT: If this is a Non-Transmitted
> BSSID, define
> + * the parent (transmitting) interface.
> + *
> + * @NL80211_ATTR_MULTIPLE_BSSID_INDEX: The index of this BSS inside
> the multi bssid
> + * element.
> + *
> + * @NL80211_ATTR_MULTIPLE_BSSID_COUNT: The number of BSSs inside the
> multi bssid element.
> + *
> + * @NL80211_ATTR_MULTIPLE_BSSID_IES: The Elements that describe our
> multiple BSS group.
> + * these get passed separately as the kernel might need to split them
> up for EMA VAP.
> + *
> * @NUM_NL80211_ATTR: total number of nl80211_attrs available
> * @NL80211_ATTR_MAX: highest attribute number currently defined
> * @__NL80211_ATTR_AFTER_LAST: internal use
> @@ -3039,6 +3053,12 @@ enum nl80211_attrs {
> NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COLOR,
> NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_IES,
>
> + NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING,
> + NL80211_ATTR_MULTIPLE_BSSID_PARENT,
> + NL80211_ATTR_MULTIPLE_BSSID_INDEX,
> + NL80211_ATTR_MULTIPLE_BSSID_COUNT,
> + NL80211_ATTR_MULTIPLE_BSSID_IES,
> +
> /* add attributes here, update the policy in nl80211.c */
>
> __NL80211_ATTR_AFTER_LAST,
> @@ -3102,6 +3122,8 @@ enum nl80211_attrs {
>
> #define NL80211_CQM_TXE_MAX_INTVL 1800
>
> +#define NL80211_MULTIPLE_BSSID_IES_MAX 8
> +
> /**
> * enum nl80211_iftype - (virtual) interface types
> *
> diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
> index 2f0bae3c6572..4ba7203ad0d2 100644
> --- a/net/wireless/nl80211.c
> +++ b/net/wireless/nl80211.c
> @@ -662,6 +662,11 @@ static const struct nla_policy
> nl80211_policy[NUM_NL80211_ATTR] = {
> [NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COUNT] = { .type = NLA_U8 },
> [NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COLOR] = { .type = NLA_U8 },
> [NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_IES] =
> NLA_POLICY_NESTED(nl80211_policy),
> + [NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING] = { .type = NLA_FLAG
> },
> + [NL80211_ATTR_MULTIPLE_BSSID_PARENT] = { .type = NLA_U32 },
> + [NL80211_ATTR_MULTIPLE_BSSID_INDEX] = { .type = NLA_U8 },
> + [NL80211_ATTR_MULTIPLE_BSSID_COUNT] = { .type = NLA_U8 },
> + [NL80211_ATTR_MULTIPLE_BSSID_IES] = { .type = NLA_NESTED },
> };
>
> /* policy for the key attributes */
> @@ -3758,6 +3763,14 @@ static int nl80211_new_interface(struct sk_buff
> *skb, struct genl_info *info)
> return err;
> }
>
> + if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING])
> + params.multiple_bssid.non_transmitted =
> + nla_get_flag(info->attrs[NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING]);
> +
> + if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT])
> + params.multiple_bssid.parent =
> + nla_get_u8(info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT]);
This should be nla_get_u32() as per the policy

> +
> if (!cfg80211_iftype_allowed(&rdev->wiphy, type, params.use_4addr,
> 0))
> return -EOPNOTSUPP;
>
> @@ -4670,6 +4683,21 @@ static int nl80211_parse_beacon(struct
> cfg80211_registered_device *rdev,
> bcn->ftm_responder = -1;
> }
>
> + if (attrs[NL80211_ATTR_MULTIPLE_BSSID_IES]) {
> + struct nlattr *nl_ie;
> + int rem_ie;
> +
> + nla_for_each_nested(nl_ie, attrs[NL80211_ATTR_MULTIPLE_BSSID_IES],
> rem_ie) {
> + if (bcn->multiple_bssid.cnt > NL80211_MULTIPLE_BSSID_IES_MAX)
> + return -EINVAL;
> + if (nla_type(nl_ie) != bcn->multiple_bssid.cnt + 1)
> + return -EINVAL;
> + bcn->multiple_bssid.ies[bcn->multiple_bssid.cnt] = nla_data(nl_ie);
> + bcn->multiple_bssid.len[bcn->multiple_bssid.cnt] = nla_len(nl_ie);
> + bcn->multiple_bssid.cnt++;
> + }
> + }
> +
> return 0;
> }
>
> @@ -5032,6 +5060,18 @@ static int nl80211_start_ap(struct sk_buff
> *skb, struct genl_info *info)
> goto out;
> }
>
> + if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_INDEX])
> + params.multiple_bssid.index = nla_get_u8(
> + info->attrs[NL80211_ATTR_MULTIPLE_BSSID_INDEX]);
> +
> + if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_COUNT])
> + params.multiple_bssid.count = nla_get_u8(
> + info->attrs[NL80211_ATTR_MULTIPLE_BSSID_COUNT]);
> +
> + if (params.multiple_bssid.non_transmitted &&
> + !info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT])
> + return -EOPNOTSUPP;
> +
> nl80211_calculate_ap_params(&params);
>
> if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])

2020-08-27 12:59:55

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH V3 1/9] nl80211: add basic multiple bssid support

On Wed, 2020-08-12 at 17:00 +0200, John Crispin wrote:
> This patch adds support for passing the multiple bssid config to the
> kernel when adding an interface. If the BSS is non-transmitting it needs
> to be indicated. A non-transmitting BSSID will have a parent interface,
> which needs to be transmitting. The multiple bssid elements are passed
> as an array.
>
> Signed-off-by: John Crispin <[email protected]>
> ---
> include/net/cfg80211.h | 35 +++++++++++++++++++++++++++++++
> include/uapi/linux/nl80211.h | 22 ++++++++++++++++++++
> net/wireless/nl80211.c | 40 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 97 insertions(+)
>
> diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
> index 541dea0fd571..0b0c730dc8d2 100644
> --- a/include/net/cfg80211.h
> +++ b/include/net/cfg80211.h
> @@ -470,6 +470,21 @@ struct ieee80211_supported_band {
> const struct ieee80211_sband_iftype_data *iftype_data;
> };
>
> +/**
> + * struct ieee80211_multiple_bssid - AP settings for multi bssid
> + *
> + * @index: the index of this AP in the multi bssid group.
> + * @count: the total number of multi bssid peer APs.
> + * @parent: a non-transmitted bssid has a transmitted parent

It obviously has a parent, but what does this u32 value mean?

> +/**
> + * struct cfg80211_multiple_bssid_data - multiple_bssid data
> + * @ies: array of extra information element(s) to add into Beacon frames for multiple
> + * bssid or %NULL
> + * @len: array of lengths of multiple_bssid.ies in octets
> + * @cnt: number of entries in multiple_bssid.ies
> + */
> +struct cfg80211_multiple_bssid_data {
> + u8 *ies[NL80211_MULTIPLE_BSSID_IES_MAX];
> + size_t len[NL80211_MULTIPLE_BSSID_IES_MAX];

This is all pretty much dynamic - why have the hard-coded limitation?
Wouldn't it be only marginally harder to do

struct ... {
int cnt;
struct {
const u8 *ies;
size_t len;
} data[];
};

and size it dynamically?

And have the driver advertise some kind of limit, I guess.

In fact, even with the patch as is, what if a driver only can do 4 not
8... Or what if your driver can do 8, but the next driver comes along
and has to bump it to 16, then your current driver will be a mess.

> + * @NL80211_ATTR_MULTIPLE_BSSID_PARENT: If this is a Non-Transmitted BSSID, define
> + * the parent (transmitting) interface.

By what? interface index?

> @@ -662,6 +662,11 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
> [NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COUNT] = { .type = NLA_U8 },
> [NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_COLOR] = { .type = NLA_U8 },
> [NL80211_ATTR_COLOR_CHANGE_ANNOUNCEMENT_IES] = NLA_POLICY_NESTED(nl80211_policy),
> + [NL80211_ATTR_MULTIPLE_BSSID_NON_TRANSMITTING] = { .type = NLA_FLAG },
> + [NL80211_ATTR_MULTIPLE_BSSID_PARENT] = { .type = NLA_U32 },
> + [NL80211_ATTR_MULTIPLE_BSSID_INDEX] = { .type = NLA_U8 },
> + [NL80211_ATTR_MULTIPLE_BSSID_COUNT] = { .type = NLA_U8 },
> + [NL80211_ATTR_MULTIPLE_BSSID_IES] = { .type = NLA_NESTED },

Maybe those should all go into a single top-level attribute with their
own nested policy? Or maybe not, I'm certainly willing to entertain
arguments eitherway.

What's the point of BSSID_COUNT by the way, you can count based on the
number of elements in the BSSID_IES array, no?


Actually, I don't understand this API at all. This is being set on a
single virtual interface. Clearly, you need a new interface for every
BSSID, transmitting or not. So why can you have many things set on a
single interface? And why do you need a count, if you know the number of
interfaces you have?


> + if (info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT])
> + params.multiple_bssid.parent =
> + nla_get_u8(info->attrs[NL80211_ATTR_MULTIPLE_BSSID_PARENT]);


As Aloka also pointed out, this must be nla_get_u32().

But I don't really like passing that down - if it's an interface index
then resolve it here and pass a pointer.

If it's something else, please document it clearly.

Thanks,
johannes