nl80211: add handling for BSS color

This patch adds the attributes, policy and parsing code to allow userland
to send the info about the BSS coloring settings to the kernel.

Signed-off-by: John Crispin <john@phrozen.org>
Link: https://lore.kernel.org/r/20191217141921.8114-1-john@phrozen.org
[johannes: remove the strict policy parsing, that was a misunderstanding]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -259,6 +259,19 @@ struct ieee80211_he_obss_pd {
 	u8 max_offset;
 };
 
+/**
+ * struct cfg80211_he_bss_color - AP settings for BSS coloring
+ *
+ * @color: the current color.
+ * @disabled: is the feature disabled.
+ * @partial: define the AID equation.
+ */
+struct cfg80211_he_bss_color {
+	u8 color;
+	bool disabled;
+	bool partial;
+};
+
 /**
  * struct ieee80211_sta_ht_cap - STA's HT capabilities
  *
@@ -990,6 +1003,7 @@ enum cfg80211_ap_settings_flags {
  * @twt_responder: Enable Target Wait Time
  * @flags: flags, as defined in enum cfg80211_ap_settings_flags
  * @he_obss_pd: OBSS Packet Detection settings
+ * @he_bss_color: BSS Color settings
  */
 struct cfg80211_ap_settings {
 	struct cfg80211_chan_def chandef;
@@ -1018,6 +1032,7 @@ struct cfg80211_ap_settings {
 	bool twt_responder;
 	u32 flags;
 	struct ieee80211_he_obss_pd he_obss_pd;
+	struct cfg80211_he_bss_color he_bss_color;
 };
 
 /**

include/uapi/linux/nl80211.h

@@ -2400,6 +2400,8 @@ enum nl80211_commands {
  * @NL80211_ATTR_VLAN_ID: VLAN ID (1..4094) for the station and VLAN group key
  *	(u16).
  *
+ * @NL80211_ATTR_HE_BSS_COLOR: nested attribute for BSS Color Settings.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -2864,6 +2866,8 @@ enum nl80211_attrs {
 
 	NL80211_ATTR_VLAN_ID,
 
+	NL80211_ATTR_HE_BSS_COLOR,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -6587,5 +6591,27 @@ enum nl80211_obss_pd_attributes {
 	NL80211_HE_OBSS_PD_ATTR_MAX = __NL80211_HE_OBSS_PD_ATTR_LAST - 1,
 };
 
+/**
+ * enum nl80211_bss_color_attributes - BSS Color attributes
+ * @__NL80211_HE_BSS_COLOR_ATTR_INVALID: Invalid
+ *
+ * @NL80211_HE_BSS_COLOR_ATTR_COLOR: the current BSS Color.
+ * @NL80211_HE_BSS_COLOR_ATTR_DISABLED: is BSS coloring disabled.
+ * @NL80211_HE_BSS_COLOR_ATTR_PARTIAL: the AID equation to be used..
+ *
+ * @__NL80211_HE_BSS_COLOR_ATTR_LAST: Internal
+ * @NL80211_HE_BSS_COLOR_ATTR_MAX: highest BSS Color attribute.
+ */
+enum nl80211_bss_color_attributes {
+	__NL80211_HE_BSS_COLOR_ATTR_INVALID,
+
+	NL80211_HE_BSS_COLOR_ATTR_COLOR,
+	NL80211_HE_BSS_COLOR_ATTR_DISABLED,
+	NL80211_HE_BSS_COLOR_ATTR_PARTIAL,
+
+	/* keep last */
+	__NL80211_HE_BSS_COLOR_ATTR_LAST,
+	NL80211_HE_BSS_COLOR_ATTR_MAX = __NL80211_HE_BSS_COLOR_ATTR_LAST - 1,
+};
 
 #endif /* __LINUX_NL80211_H */

net/wireless/nl80211.c

@@ -321,6 +321,13 @@ he_obss_pd_policy[NL80211_HE_OBSS_PD_ATTR_MAX + 1] = {
 		NLA_POLICY_RANGE(NLA_U8, 1, 20),
 };
 
+static const struct nla_policy
+he_bss_color_policy[NL80211_HE_BSS_COLOR_ATTR_MAX + 1] = {
+	[NL80211_HE_BSS_COLOR_ATTR_COLOR] = NLA_POLICY_RANGE(NLA_U8, 1, 63),
+	[NL80211_HE_BSS_COLOR_ATTR_DISABLED] = { .type = NLA_FLAG },
+	[NL80211_HE_BSS_COLOR_ATTR_PARTIAL] = { .type = NLA_FLAG },
+};
+
 const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[0] = { .strict_start_type = NL80211_ATTR_HE_OBSS_PD },
 	[NL80211_ATTR_WIPHY] = { .type = NLA_U32 },
@@ -625,6 +632,7 @@ const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_TWT_RESPONDER] = { .type = NLA_FLAG },
 	[NL80211_ATTR_HE_OBSS_PD] = NLA_POLICY_NESTED(he_obss_pd_policy),
 	[NL80211_ATTR_VLAN_ID] = NLA_POLICY_RANGE(NLA_U16, 1, VLAN_N_VID - 2),
+	[NL80211_ATTR_HE_BSS_COLOR] = NLA_POLICY_NESTED(he_bss_color_policy),
 };
 
 /* policy for the key attributes */
@@ -4511,6 +4519,30 @@ static int nl80211_parse_he_obss_pd(struct nlattr *attrs,
 	return 0;
 }
 
+static int nl80211_parse_he_bss_color(struct nlattr *attrs,
+				      struct cfg80211_he_bss_color *he_bss_color)
+{
+	struct nlattr *tb[NL80211_HE_BSS_COLOR_ATTR_MAX + 1];
+	int err;
+
+	err = nla_parse_nested(tb, NL80211_HE_BSS_COLOR_ATTR_MAX, attrs,
+			       he_bss_color_policy, NULL);
+	if (err)
+		return err;
+
+	if (!tb[NL80211_HE_BSS_COLOR_ATTR_COLOR])
+		return -EINVAL;
+
+	he_bss_color->color =
+		nla_get_u8(tb[NL80211_HE_BSS_COLOR_ATTR_COLOR]);
+	he_bss_color->disabled =
+		nla_get_flag(tb[NL80211_HE_BSS_COLOR_ATTR_DISABLED]);
+	he_bss_color->partial =
+		nla_get_flag(tb[NL80211_HE_BSS_COLOR_ATTR_PARTIAL]);
+
+	return 0;
+}
+
 static void nl80211_check_ap_rate_selectors(struct cfg80211_ap_settings *params,
 					    const u8 *rates)
 {
@@ -4803,6 +4835,14 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 			return err;
 	}
 
+	if (info->attrs[NL80211_ATTR_HE_BSS_COLOR]) {
+		err = nl80211_parse_he_bss_color(
+					info->attrs[NL80211_ATTR_HE_BSS_COLOR],
+					&params.he_bss_color);
+		if (err)
+			return err;
+	}
+
 	nl80211_calculate_ap_params(&params);
 
 	if (info->attrs[NL80211_ATTR_EXTERNAL_AUTH_SUPPORT])