This patch adds new attributes to support unsolicited broadcast
probe response transmission used for in-band
discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior for
fast passive scanning).
The new attribute, NL80211_ATTR_UNSOL_BCAST_PROBE_RESP, is nested which
supports following parameters:
(1) NL80211_UNSOL_BCAST_PROBE_RESP_INT - Packet interval
(2) NL80211_UNSOL_BCAST_PROBE_RESP_TMPL - Template data
Signed-off-by: Aloka Dixit <[email protected]>
---
include/net/cfg80211.h | 18 ++++++++++++++
include/uapi/linux/nl80211.h | 32 ++++++++++++++++++++++++
net/wireless/nl80211.c | 47 ++++++++++++++++++++++++++++++++++++
3 files changed, 97 insertions(+)
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index fc7e8807838d..884050bf5c74 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1047,6 +1047,22 @@ struct cfg80211_acl_data {
struct mac_address mac_addrs[];
};
+/**
+ * struct cfg80211_unsol_bcast_probe_resp - Unsolicited broadcast probe
+ * response parameters in 6GHz.
+ *
+ * @interval: Packet interval in TUs. Maximum allowed is 20 TU, as mentioned
+ * in IEEE P802.11ax/D6.0 26.17.2.3.2 - AP behavior for fast passive
+ * scanning
+ * @tmpl_len: Template length
+ * @tmpl: Template data for probe response
+ */
+struct cfg80211_unsol_bcast_probe_resp {
+ u32 interval;
+ size_t tmpl_len;
+ const u8 *tmpl;
+};
+
/**
* enum cfg80211_ap_settings_flags - AP settings flags
*
@@ -1094,6 +1110,7 @@ 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)
+ * @unsol_bcast_probe_resp: Unsolicited broadcast probe response parameters
*/
struct cfg80211_ap_settings {
struct cfg80211_chan_def chandef;
@@ -1124,6 +1141,7 @@ struct cfg80211_ap_settings {
u32 flags;
struct ieee80211_he_obss_pd he_obss_pd;
struct cfg80211_he_bss_color he_bss_color;
+ struct cfg80211_unsol_bcast_probe_resp unsol_bcast_probe_resp;
};
/**
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 4e6339ab1fce..f3e6a37f0df8 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2505,6 +2505,10 @@ enum nl80211_commands {
* @NL80211_ATTR_HE_6GHZ_CAPABILITY: HE 6 GHz Band Capability element (from
* association request when used with NL80211_CMD_NEW_STATION).
*
+ * @NL80211_ATTR_UNSOL_BCAST_PROBE_RESP: Optional parameter to configure
+ * unsolicited broadcast probe response. It is a nested attribute, see
+ * &enum nl80211_unsol_bcast_probe_resp_attributes.
+ *
* @NUM_NL80211_ATTR: total number of nl80211_attrs available
* @NL80211_ATTR_MAX: highest attribute number currently defined
* @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2987,6 +2991,8 @@ enum nl80211_attrs {
NL80211_ATTR_HE_6GHZ_CAPABILITY,
+ NL80211_ATTR_UNSOL_BCAST_PROBE_RESP,
+
/* add attributes here, update the policy in nl80211.c */
__NL80211_ATTR_AFTER_LAST,
@@ -6922,4 +6928,30 @@ enum nl80211_iftype_akm_attributes {
NL80211_IFTYPE_AKM_ATTR_MAX = __NL80211_IFTYPE_AKM_ATTR_LAST - 1,
};
+/**
+ * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited broadcast probe
+ * response configuration. Applicable only in 6GHz.
+ *
+ * @__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID: Invalid
+ *
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_INT: Maximum packet interval (u32, TU).
+ * Allowed range: 0..20 (TU = Time Unit). IEEE P802.11ax/D6.0
+ * 26.17.2.3.2 (AP behavior for fast passive scanning.
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_TMPL: Unsolicited broadcast probe response
+ * frame template (binary).
+ *
+ * @__NL80211_UNSOL_BCAST_PROBE_RESP_LAST: Internal
+ * @NL80211_UNSOL_BCAST_PROBE_RESP_MAX: highest attribute
+ */
+enum nl80211_unsol_bcast_probe_resp_attributes {
+ __NL80211_UNSOL_BCAST_PROBE_RESP_INVALID,
+
+ NL80211_UNSOL_BCAST_PROBE_RESP_INT,
+ NL80211_UNSOL_BCAST_PROBE_RESP_TMPL,
+
+ /* keep last */
+ __NL80211_UNSOL_BCAST_PROBE_RESP_LAST,
+ NL80211_UNSOL_BCAST_PROBE_RESP_MAX =
+ __NL80211_UNSOL_BCAST_PROBE_RESP_LAST - 1
+};
#endif /* __LINUX_NL80211_H */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 263ae395ad44..d42056421e55 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -338,6 +338,13 @@ static const struct nla_policy nl80211_txattr_policy[NL80211_TXRATE_MAX + 1] = {
[NL80211_TXRATE_GI] = { .type = NLA_U8 },
};
+static const struct nla_policy
+unsol_bcast_probe_resp_policy[NL80211_UNSOL_BCAST_PROBE_RESP_MAX + 1] = {
+ [NL80211_UNSOL_BCAST_PROBE_RESP_INT] = NLA_POLICY_MAX(NLA_U32, 20),
+ [NL80211_UNSOL_BCAST_PROBE_RESP_TMPL] = { .type = NLA_BINARY,
+ .len = IEEE80211_MAX_DATA_LEN }
+};
+
static const struct nla_policy
nl80211_tid_config_attr_policy[NL80211_TID_CONFIG_ATTR_MAX + 1] = {
[NL80211_TID_CONFIG_ATTR_VIF_SUPP] = { .type = NLA_U64 },
@@ -658,6 +665,9 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
.type = NLA_EXACT_LEN,
.len = sizeof(struct ieee80211_he_6ghz_capa),
},
+
+ [NL80211_ATTR_UNSOL_BCAST_PROBE_RESP] =
+ NLA_POLICY_NESTED(unsol_bcast_probe_resp_policy),
};
/* policy for the key attributes */
@@ -4721,6 +4731,35 @@ static int nl80211_parse_he_bss_color(struct nlattr *attrs,
return 0;
}
+static int
+nl80211_parse_unsol_bcast_probe_resp(struct nlattr *attrs,
+ struct cfg80211_ap_settings *params)
+{
+ struct nlattr *tmpl;
+ struct nlattr *tb[NL80211_UNSOL_BCAST_PROBE_RESP_MAX + 1];
+ int ret;
+ struct cfg80211_unsol_bcast_probe_resp *presp =
+ ¶ms->unsol_bcast_probe_resp;
+
+ ret = nla_parse_nested(tb, NL80211_UNSOL_BCAST_PROBE_RESP_MAX, attrs,
+ unsol_bcast_probe_resp_policy, NULL);
+ if (ret)
+ return ret;
+
+ if (!tb[NL80211_UNSOL_BCAST_PROBE_RESP_INT])
+ return -EINVAL;
+
+ presp->interval = nla_get_u32(tb[NL80211_UNSOL_BCAST_PROBE_RESP_INT]);
+
+ tmpl = tb[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL];
+ if (tmpl) {
+ presp->tmpl = nla_data(tmpl);
+ presp->tmpl_len = nla_len(tmpl);
+ }
+
+ return 0;
+}
+
static void nl80211_check_ap_rate_selectors(struct cfg80211_ap_settings *params,
const u8 *rates)
{
@@ -5027,6 +5066,14 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
return err;
}
+ if (info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP]) {
+ err = nl80211_parse_unsol_bcast_probe_resp(
+ info->attrs[NL80211_ATTR_UNSOL_BCAST_PROBE_RESP],
+ ¶ms);
+ if (err)
+ return err;
+ }
+
nl80211_calculate_ap_params(¶ms);
if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])
--
2.25.0
> +/**
> + * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited broadcast probe
> + * response configuration. Applicable only in 6GHz.
> + *
> + * @__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID: Invalid
> + *
> + * @NL80211_UNSOL_BCAST_PROBE_RESP_INT: Maximum packet interval (u32, TU).
> + * Allowed range: 0..20 (TU = Time Unit). IEEE P802.11ax/D6.0
> + * 26.17.2.3.2 (AP behavior for fast passive scanning.
nit: that "(" never closes
> + tmpl = tb[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL];
> + if (tmpl) {
> + presp->tmpl = nla_data(tmpl);
> + presp->tmpl_len = nla_len(tmpl);
> + }
>
So, hmm. Similar question here - what do you do without a template? Or
OTOH, why do you even need a template? Would you advertise something
that's *different* from the regular probe response template you already
get for offloaded probe request/response support?
johannes
On Wed, 2020-07-15 at 16:05 -0700, Aloka Dixit wrote:
> This patch adds new attributes to support unsolicited broadcast
> probe response transmission used for in-band
> discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior for
> fast passive scanning).
> The new attribute, NL80211_ATTR_UNSOL_BCAST_PROBE_RESP, is nested which
> supports following parameters:
> (1) NL80211_UNSOL_BCAST_PROBE_RESP_INT - Packet interval
> (2) NL80211_UNSOL_BCAST_PROBE_RESP_TMPL - Template data
And maybe some driver support flag is needed?
johannes
On Mon, 2020-08-03 at 12:20 +0200, Johannes Berg wrote:
> On Wed, 2020-07-15 at 16:05 -0700, Aloka Dixit wrote:
> > This patch adds new attributes to support unsolicited broadcast
> > probe response transmission used for in-band
> > discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior for
> > fast passive scanning).
> > The new attribute, NL80211_ATTR_UNSOL_BCAST_PROBE_RESP, is nested which
> > supports following parameters:
> > (1) NL80211_UNSOL_BCAST_PROBE_RESP_INT - Packet interval
> > (2) NL80211_UNSOL_BCAST_PROBE_RESP_TMPL - Template data
>
> And maybe some driver support flag is needed?
Possibly even per band, like our discussion on the other patches?
johannes
Also,
> +/**
> + * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited broadcast probe
> + * response configuration. Applicable only in 6GHz.
> + *
> + * @__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID: Invalid
> + *
> + * @NL80211_UNSOL_BCAST_PROBE_RESP_INT: Maximum packet interval (u32, TU).
> + * Allowed range: 0..20 (TU = Time Unit). IEEE P802.11ax/D6.0
0 doesn't make sense, you should disallow that.
I see you used it for "turn off" at least in the mac80211 patch but it
seems to me that should have a more explicit way at least in the
external API? At the very least it needs to documentation.
johannes
On 2020-08-03 03:18, Johannes Berg wrote:
>> +/**
>> + * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited
>> broadcast probe
>> + * response configuration. Applicable only in 6GHz.
>> + *
>> + * @__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID: Invalid
>> + *
>> + * @NL80211_UNSOL_BCAST_PROBE_RESP_INT: Maximum packet interval (u32,
>> TU).
>> + * Allowed range: 0..20 (TU = Time Unit). IEEE P802.11ax/D6.0
>> + * 26.17.2.3.2 (AP behavior for fast passive scanning.
>
> nit: that "(" never closes
>
>> + tmpl = tb[NL80211_UNSOL_BCAST_PROBE_RESP_TMPL];
>> + if (tmpl) {
>> + presp->tmpl = nla_data(tmpl);
>> + presp->tmpl_len = nla_len(tmpl);
>> + }
>>
> So, hmm. Similar question here - what do you do without a template? Or
> OTOH, why do you even need a template? Would you advertise something
> that's *different* from the regular probe response template you already
> get for offloaded probe request/response support?
>
The template will be same as the probe response, except for the
destination MAC address as this one is broadcast.
Main reason is that this unsolicited broadcast probe response
transmission is specific to 6GHz and not applicable to lower bands.
Having a separate netlink command allowed not messing with the existing
probe response offload feature which is for all bands. Thanks.
> johannes
On 2020-08-03 03:20, Johannes Berg wrote:
> Also,
>
>> +/**
>> + * enum nl80211_unsol_bcast_probe_resp_attributes - Unsolicited
>> broadcast probe
>> + * response configuration. Applicable only in 6GHz.
>> + *
>> + * @__NL80211_UNSOL_BCAST_PROBE_RESP_INVALID: Invalid
>> + *
>> + * @NL80211_UNSOL_BCAST_PROBE_RESP_INT: Maximum packet interval (u32,
>> TU).
>> + * Allowed range: 0..20 (TU = Time Unit). IEEE P802.11ax/D6.0
>
> 0 doesn't make sense, you should disallow that.
>
> I see you used it for "turn off" at least in the mac80211 patch but it
> seems to me that should have a more explicit way at least in the
> external API? At the very least it needs to documentation.
>
> johannes
Hi Johannes, interval=0 means 'disable' is given in the specification,
will extend the documentation to mention that.
On 2020-08-03 03:20, Johannes Berg wrote:
> On Wed, 2020-07-15 at 16:05 -0700, Aloka Dixit wrote:
>> This patch adds new attributes to support unsolicited broadcast
>> probe response transmission used for in-band
>> discovery in 6GHz band (IEEE P802.11ax/D6.0 26.17.2.3.2, AP behavior
>> for
>> fast passive scanning).
>> The new attribute, NL80211_ATTR_UNSOL_BCAST_PROBE_RESP, is nested
>> which
>> supports following parameters:
>> (1) NL80211_UNSOL_BCAST_PROBE_RESP_INT - Packet interval
>> (2) NL80211_UNSOL_BCAST_PROBE_RESP_TMPL - Template data
>
> And maybe some driver support flag is needed?
>
> johannes
Are you referring to enable/disable flag separate from the interval
field being used for that? Or a different command/event from driver to
netlink advertising if the driver supports this feature?
If former, it isn't needed because interval=0 means disable.
Thanks.