From 0b5aeb89eb5cfb8fc799f499dbce999b659ec2f4 Mon Sep 17 00:00:00 2001
From: Adrian Chadd <adrian@FreeBSD.org>
Date: Fri, 5 Jun 2020 00:11:44 +0000
Subject: [PATCH] [net80211] Send a probe request after IBSS node discovery

This sends a probe request after IBSS node discovery through
beacon frames. This allows things like HT and VHT capabilities
to be "negotiated" in adhoc mode.

It is .. kinda fire and pray - this isn't retried after discovery
so it's quite possible that nodes occasionally don't come up with
HT/VHT rate upgrades. At some point it may be a fun side project
to add support for retrying these probe requests/negotiations
after IBSS node discovery.

Tested:

* tested with multiple ath(4) NICs in 11n mode.

Differential Revision:	https://reviews.freebsd.org/D24979
---
 sys/net80211/ieee80211_adhoc.c | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/sys/net80211/ieee80211_adhoc.c b/sys/net80211/ieee80211_adhoc.c
index 24f6ba448e7..ea1519b3381 100644
--- a/sys/net80211/ieee80211_adhoc.c
+++ b/sys/net80211/ieee80211_adhoc.c
@@ -715,6 +715,15 @@ adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 	wh = mtod(m0, struct ieee80211_frame *);
 	frm = (uint8_t *)&wh[1];
 	efrm = mtod(m0, uint8_t *) + m0->m_len;
+
+	IEEE80211_DPRINTF(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
+	    "%s: recv mgmt frame, addr2=%6D, ni=%p (%6D) fc=%.02x %.02x\n",
+	    __func__,
+	    wh->i_addr2, ":",
+	    ni,
+	    ni->ni_macaddr, ":",
+	    wh->i_fc[0],
+	    wh->i_fc[1]);
 	switch (subtype) {
 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
 	case IEEE80211_FC0_SUBTYPE_BEACON: {
@@ -788,6 +797,20 @@ adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 				} else
 					ni = NULL;
 
+				/*
+				 * Send a probe request so we announce 11n
+				 * capabilities.
+				 *
+				 * Don't do this if we're scanning.
+				 */
+				if (! (ic->ic_flags & IEEE80211_F_SCAN))
+					ieee80211_send_probereq(ni, /* node */
+						vap->iv_myaddr, /* SA */
+						ni->ni_macaddr, /* DA */
+						vap->iv_bss->ni_bssid, /* BSSID */
+						vap->iv_bss->ni_essid,
+						vap->iv_bss->ni_esslen); /* SSID */
+
 			} else if (ni->ni_capinfo == 0) {
 				/*
 				 * Update faked node created on transmit.
@@ -936,11 +959,11 @@ adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 			vap->iv_stats.is_rx_mgtdiscard++;
 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
 		    !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
-			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
+			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
 			    wh, NULL, "%s", "not for us");
 			vap->iv_stats.is_rx_mgtdiscard++;
 		} else if (vap->iv_state != IEEE80211_S_RUN) {
-			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
+			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
 			    wh, NULL, "wrong state %s",
 			    ieee80211_state_name[vap->iv_state]);
 			vap->iv_stats.is_rx_mgtdiscard++;