[PATCH 5/9] hostapd: mask out not-supported vht caps

[eliad at wizery.com]

From: Eliad Peller <eliad at wizery.com>

mask the remote vht caps with our own caps, similarly
to what being done for ht caps.

Signed-hostap: Eliad Peller <eliadx.peller at intel.com>
---
 src/ap/ieee802_11_vht.c      |   52 +++++++++++++++++++++++++++++++++++++++++-
 src/common/ieee802_11_defs.h |    1 +
 2 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/src/ap/ieee802_11_vht.c b/src/ap/ieee802_11_vht.c
index 0012c0f..547a917 100644
--- a/src/ap/ieee802_11_vht.c
+++ b/src/ap/ieee802_11_vht.c
@@ -113,9 +113,59 @@ void hostapd_get_vht_capab(struct hostapd_data *hapd,
 			   struct ieee80211_vht_capabilities *vht_cap,
 			   struct ieee80211_vht_capabilities *neg_vht_cap)
 {
+	u32 cap, own_cap, sym_caps;
+
 	if (vht_cap == NULL)
 		return;
 	os_memcpy(neg_vht_cap, vht_cap, sizeof(*neg_vht_cap));
 
-	/* TODO: mask own capabilities, like get_ht_capab() */
+	cap = le_to_host32(neg_vht_cap->vht_capabilities_info);
+	own_cap = hapd->iconf->vht_capab;
+
+	/* mask out symmetric VHT capabilities we don't support. */
+	sym_caps = VHT_CAP_SHORT_GI_80 | VHT_CAP_SHORT_GI_160;
+	cap &= ~sym_caps | (own_cap & sym_caps);
+
+	/* mask out beamformer/beamformee caps if not supported */
+	if (!(own_cap & VHT_CAP_SU_BEAMFORMER_CAPABLE))
+		cap &= ~(VHT_CAP_SU_BEAMFORMEE_CAPABLE |
+			 VHT_CAP_BEAMFORMEE_STS_MAX);
+
+	if (!(own_cap & VHT_CAP_SU_BEAMFORMEE_CAPABLE))
+		cap &= ~(VHT_CAP_SU_BEAMFORMER_CAPABLE |
+			 VHT_CAP_SOUNDING_DIMENSION_MAX);
+
+	if (!(own_cap & VHT_CAP_MU_BEAMFORMER_CAPABLE))
+		cap &= ~VHT_CAP_MU_BEAMFORMEE_CAPABLE;
+
+	if (!(own_cap & VHT_CAP_MU_BEAMFORMEE_CAPABLE))
+		cap &= ~VHT_CAP_MU_BEAMFORMER_CAPABLE;
+
+	/* mask channels widths we don't support */
+	switch (own_cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
+	case VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
+		break;
+	case VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
+		if (cap & VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
+			cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ;
+			cap |= VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
+		}
+		break;
+	default:
+		cap &= ~VHT_CAP_SUPP_CHAN_WIDTH_MASK;
+	}
+
+	if (!(cap & VHT_CAP_SUPP_CHAN_WIDTH_MASK))
+		cap &= ~VHT_CAP_SHORT_GI_160;
+
+	/*
+	 * if we don't support RX STBC, mask out TX STBC in the STA's HT caps
+	 * if we don't support TX STBC, mask out RX STBC in the STA's HT caps
+	 */
+	if (!(own_cap & VHT_CAP_RXSTBC_MASK))
+		cap &= ~VHT_CAP_TXSTBC;
+	if (!(own_cap & VHT_CAP_TXSTBC))
+		cap &= ~VHT_CAP_RXSTBC_MASK;
+
+	neg_vht_cap->vht_capabilities_info = host_to_le32(cap);
 }
diff --git a/src/common/ieee802_11_defs.h b/src/common/ieee802_11_defs.h
index 67f6451..61e5ae0 100644
--- a/src/common/ieee802_11_defs.h
+++ b/src/common/ieee802_11_defs.h
@@ -705,6 +705,7 @@ struct ieee80211_vht_operation {
 #define VHT_CAP_MAX_MPDU_LENGTH_MASK                ((u32) BIT(0) | BIT(1))
 #define VHT_CAP_SUPP_CHAN_WIDTH_160MHZ              ((u32) BIT(2))
 #define VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ     ((u32) BIT(3))
+#define VHT_CAP_SUPP_CHAN_WIDTH_MASK                ((u32) BIT(2) | BIT(3))
 #define VHT_CAP_RXLDPC                              ((u32) BIT(4))
 #define VHT_CAP_SHORT_GI_80                         ((u32) BIT(5))
 #define VHT_CAP_SHORT_GI_160                        ((u32) BIT(6))
-- 
1.7.10.4