nl80211: Add API to support VHT MU-MIMO air sniffer

add API to support VHT MU-MIMO air sniffer.
in MU-MIMO there are parallel frames on the air while the HW
has only one RX.
add the capability to sniff one of the MU-MIMO parallel frames by
giving the sniffer additional information so it'll know which
of the parallel frames it shall follow.

Add attribute - NL80211_ATTR_MU_MIMO_GROUP_DATA - for getting
a MU-MIMO groupID in order to monitor packets from that group
using VHT MU-MIMO.
And add attribute -NL80211_ATTR_MU_MIMO_FOLLOW_ADDR - for passing
MAC address to monitor mode.
that option will be used by VHT MU-MIMO air sniffer to follow a
station according to it's MAC address using VHT MU-MIMO.

Signed-off-by: Aviya Erenfeld <aviya.erenfeld@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 244d552d5647..447026f8cc76 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -405,6 +405,10 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
         [NL80211_ATTR_PBSS] = { .type = NLA_FLAG },
         [NL80211_ATTR_BSS_SELECT] = { .type = NLA_NESTED },
         [NL80211_ATTR_STA_SUPPORT_P2P_PS] = { .type = NLA_U8 },
+        [NL80211_ATTR_MU_MIMO_GROUP_DATA] = {
+                .len = VHT_MUMIMO_GROUPS_DATA_LEN
+        },
+        [NL80211_ATTR_MU_MIMO_FOLLOW_MAC_ADDR] = { .len = ETH_ALEN },
 };
 
 /* policy for the key attributes */
@@ -2695,6 +2699,38 @@ static int nl80211_set_interface(struct sk_buff *skb, struct genl_info *info)
                 change = true;
         }
 
+        if (info->attrs[NL80211_ATTR_MU_MIMO_GROUP_DATA]) {
+                const u8 *mumimo_groups;
+                u32 cap_flag = NL80211_EXT_FEATURE_MU_MIMO_AIR_SNIFFER;
+
+                if (!wiphy_ext_feature_isset(&rdev->wiphy, cap_flag))
+                        return -EOPNOTSUPP;
+
+                mumimo_groups =
+                        nla_data(info->attrs[NL80211_ATTR_MU_MIMO_GROUP_DATA]);
+
+                /* bits 0 and 63 are reserved and must be zero */
+                if ((mumimo_groups[0] & BIT(7)) ||
+                    (mumimo_groups[VHT_MUMIMO_GROUPS_DATA_LEN - 1] & BIT(0)))
+                        return -EINVAL;
+
+                memcpy(params.vht_mumimo_groups, mumimo_groups,
+                       VHT_MUMIMO_GROUPS_DATA_LEN);
+                change = true;
+        }
+
+        if (info->attrs[NL80211_ATTR_MU_MIMO_FOLLOW_MAC_ADDR]) {
+                u32 cap_flag = NL80211_EXT_FEATURE_MU_MIMO_AIR_SNIFFER;
+
+                if (!wiphy_ext_feature_isset(&rdev->wiphy, cap_flag))
+                        return -EOPNOTSUPP;
+
+                nla_memcpy(params.macaddr,
+                           info->attrs[NL80211_ATTR_MU_MIMO_FOLLOW_MAC_ADDR],
+                           ETH_ALEN);
+                change = true;
+        }
+
         if (flags && (*flags & MONITOR_FLAG_ACTIVE) &&
             !(rdev->wiphy.features & NL80211_FEATURE_ACTIVE_MONITOR))
                 return -EOPNOTSUPP;