[PATCH] AP: Do not set reserved bits in HE Capabilities elements

[Pablo MARTIN-GOMEZ]

Currently, bits are set in the Supported Channel Width Set subfields in
the HE Capabilities elements regardless of the current band. However,
table 9-322b from 802.11ax standard indicates that some bits are
reserved depending on the current band. Convention states that reserved
bits shall be set to zero unless otherwise stated.

Set bits according to current band and supported widths.

Signed-off-by: Pablo Martin-Gomez <pmartin-gomez at freebox.fr>
---
  src/ap/ieee802_11_he.c | 48 ++++++++++++++++++++++++++----------------
  1 file changed, 30 insertions(+), 18 deletions(-)

diff --git a/src/ap/ieee802_11_he.c b/src/ap/ieee802_11_he.c
index cc731b914..f4adeada9 100644
--- a/src/ap/ieee802_11_he.c
+++ b/src/ap/ieee802_11_he.c
@@ -91,7 +91,7 @@ u8 * hostapd_eid_he_capab(struct hostapd_data *hapd, 
u8 *eid,
  {
      struct ieee80211_he_capabilities *cap;
      struct hostapd_hw_modes *mode = hapd->iface->current_mode;
-    u8 he_oper_chwidth = ~HE_PHYCAP_CHANNEL_WIDTH_MASK;
+    u8 he_oper_chwidth = 0;
      u8 *pos = eid;
      u8 ie_size = 0, mcs_nss_size = 4, ppet_size = 0;

@@ -102,23 +102,35 @@ u8 * hostapd_eid_he_capab(struct hostapd_data 
*hapd, u8 *eid,
      ppet_size = ieee80211_he_ppet_size(mode->he_capab[opmode].ppet[0],
                         mode->he_capab[opmode].phy_cap);

-    switch (hapd->iface->conf->he_oper_chwidth) {
-    case CONF_OPER_CHWIDTH_80P80MHZ:
-        he_oper_chwidth |=
-            HE_PHYCAP_CHANNEL_WIDTH_SET_80PLUS80MHZ_IN_5G;
-        mcs_nss_size += 4;
-        /* fall through */
-    case CONF_OPER_CHWIDTH_160MHZ:
-        he_oper_chwidth |= HE_PHYCAP_CHANNEL_WIDTH_SET_160MHZ_IN_5G;
-        mcs_nss_size += 4;
-        /* fall through */
-    case CONF_OPER_CHWIDTH_80MHZ:
-    case CONF_OPER_CHWIDTH_USE_HT:
-        he_oper_chwidth |= HE_PHYCAP_CHANNEL_WIDTH_SET_40MHZ_IN_2G |
-            HE_PHYCAP_CHANNEL_WIDTH_SET_40MHZ_80MHZ_IN_5G;
-        break;
-    default:
-        break;
+    if (mode->mode == HOSTAPD_MODE_IEEE80211A) {
+        switch (hapd->iface->conf->he_oper_chwidth) {
+        case CONF_OPER_CHWIDTH_80P80MHZ:
+            he_oper_chwidth |=
+                HE_PHYCAP_CHANNEL_WIDTH_SET_80PLUS80MHZ_IN_5G;
+            mcs_nss_size += 4;
+            /* fall through */
+        case CONF_OPER_CHWIDTH_160MHZ:
+            he_oper_chwidth |= HE_PHYCAP_CHANNEL_WIDTH_SET_160MHZ_IN_5G;
+            mcs_nss_size += 4;
+            /* fall through */
+        case CONF_OPER_CHWIDTH_80MHZ:
+        case CONF_OPER_CHWIDTH_USE_HT:
+            he_oper_chwidth |= 
HE_PHYCAP_CHANNEL_WIDTH_SET_40MHZ_80MHZ_IN_5G;
+            break;
+        default:
+            break;
+        }
+    } else  {
+        switch (hapd->iface->conf->he_oper_chwidth) {
+        case CONF_OPER_CHWIDTH_80P80MHZ:
+        case CONF_OPER_CHWIDTH_160MHZ:
+        case CONF_OPER_CHWIDTH_80MHZ:
+        case CONF_OPER_CHWIDTH_USE_HT:
+            he_oper_chwidth |= HE_PHYCAP_CHANNEL_WIDTH_SET_40MHZ_IN_2G;
+            break;
+        default:
+            break;
+        }
      }

      ie_size += mcs_nss_size + ppet_size;
-- 
2.43.0