WPA: driver_bsd.c: backout upstream IFF_ change and add logging

This reverts the state to our old supplicant logic setting or clearing
IFF_UP if needed.  In addition this adds logging for the cases in which
we do (not) change the interface state.

Depending on testing this seems to help bringing WiFi up or not log
any needed changes (which would be the expected wpa_supplicant logic
now).  People should look out for ``(changed)`` log entries (at least
if debugging the issue; this way we will at least have data points).

There is a hypothesis still pondered that the entire IFF_UP toggling
only exploits a race in net80211 (see further discssussions for more
debugging and alternative solutions see D38508 and D38753).
That may also explain why the changes to the rc startup script [1]
only helped partially for some people to no longer see the
continuous CTRL-EVENT-SCAN-FAILED.

It is highly likely that we will want further changes and until
we know for sure that people are seeing ''(changed)'' events
this should stay local.  Should we need to upstream this we'll
likely need #ifdef __FreeBSD__ around this code.

[1] 5fcdc19a81 and
    d06d7eb091

Sponsored by:	The FreeBSD Foundation
MFC after:	10 days
Reviewed by:	cy, enweiwu (earlier)
Differential Revision: https://reviews.freebsd.org/D38807

contrib/wpa/src/drivers/driver_bsd.c

@@ -294,8 +294,9 @@ bsd_send_mlme_param(void *priv, const u8 op, const u16 reason, const u8 *addr)
 }
 
 static int
-bsd_get_iface_flags(struct bsd_driver_data *drv)
+bsd_ctrl_iface(void *priv, int enable)
 {
+	struct bsd_driver_data *drv = priv;
 	struct ifreq ifr;
 
 	os_memset(&ifr, 0, sizeof(ifr));
@@ -307,6 +308,33 @@ bsd_get_iface_flags(struct bsd_driver_data *drv)
 		return -1;
 	}
 	drv->flags = ifr.ifr_flags;
+
+
+	if (enable) {
+		if (ifr.ifr_flags & IFF_UP)
+			goto nochange;
+		ifr.ifr_flags |= IFF_UP;
+	} else {
+		if (!(ifr.ifr_flags & IFF_UP))
+			goto nochange;
+		ifr.ifr_flags &= ~IFF_UP;
+	}
+
+	if (ioctl(drv->global->sock, SIOCSIFFLAGS, &ifr) < 0) {
+		wpa_printf(MSG_ERROR, "ioctl[SIOCSIFFLAGS]: %s",
+			   strerror(errno));
+		return -1;
+	}
+
+	wpa_printf(MSG_DEBUG, "%s: if %s (changed) enable %d IFF_UP %d ",
+	    __func__, drv->ifname, enable, ((ifr.ifr_flags & IFF_UP) != 0));
+
+	drv->flags = ifr.ifr_flags;
+	return 0;
+
+nochange:
+	wpa_printf(MSG_DEBUG, "%s: if %s (no change) enable %d IFF_UP %d ",
+	    __func__, drv->ifname, enable, ((ifr.ifr_flags & IFF_UP) != 0));
 	return 0;
 }
 
@@ -526,7 +554,7 @@ bsd_set_ieee8021x(void *priv, struct wpa_bss_params *params)
 			   __func__);
 		return -1;
 	}
-	return 0;
+	return bsd_ctrl_iface(priv, 1);
 }
 
 static void
@@ -1030,7 +1058,8 @@ bsd_init(struct hostapd_data *hapd, struct wpa_init_params *params)
 	if (l2_packet_get_own_addr(drv->sock_xmit, params->own_addr))
 		goto bad;
 
-	if (bsd_get_iface_flags(drv) < 0)
+	/* mark down during setup */
+	if (bsd_ctrl_iface(drv, 0) < 0)
 		goto bad;
 
 	if (bsd_set_mediaopt(drv, IFM_OMASK, IFM_IEEE80211_HOSTAP) < 0) {
@@ -1055,12 +1084,13 @@ bsd_deinit(void *priv)
 {
 	struct bsd_driver_data *drv = priv;
 
+	if (drv->ifindex != 0)
+		bsd_ctrl_iface(drv, 0);
 	if (drv->sock_xmit != NULL)
 		l2_packet_deinit(drv->sock_xmit);
 	os_free(drv);
 }
 
-
 static int
 bsd_set_sta_authorized(void *priv, const u8 *addr,
 		       unsigned int total_flags, unsigned int flags_or,
@@ -1309,7 +1339,7 @@ wpa_driver_bsd_associate(void *priv, struct wpa_driver_associate_params *params)
 	 * NB: interface must be marked UP for association
 	 * or scanning (ap_scan=2)
 	 */
-	if (bsd_get_iface_flags(drv) < 0)
+	if (bsd_ctrl_iface(drv, 1) < 0)
 		return -1;
 
 	os_memset(&mlme, 0, sizeof(mlme));
@@ -1354,11 +1384,8 @@ wpa_driver_bsd_scan(void *priv, struct wpa_driver_scan_params *params)
 	}
 
 	/* NB: interface must be marked UP to do a scan */
-	if (!(drv->flags & IFF_UP)) {
+	if (bsd_ctrl_iface(drv, 1) < 0)
-		wpa_printf(MSG_DEBUG, "%s: interface is not up, cannot scan",
-			   __func__);
 		return -1;
-	}
 
 #ifdef IEEE80211_IOC_SCAN_MAX_SSID
 	os_memset(&sr, 0, sizeof(sr));
@@ -1664,7 +1691,7 @@ wpa_driver_bsd_init(void *ctx, const char *ifname, void *priv)
 		drv->capa.key_mgmt_iftype[i] = drv->capa.key_mgmt;
 
 	/* Down interface during setup. */
-	if (bsd_get_iface_flags(drv) < 0)
+	if (bsd_ctrl_iface(drv, 0) < 0)
 		goto fail;
 
 	/* Proven to work, lets go! */
@@ -1688,6 +1715,9 @@ wpa_driver_bsd_deinit(void *priv)
 	if (drv->ifindex != 0 && !drv->if_removed) {
 		wpa_driver_bsd_set_wpa(drv, 0);
 
+		/* NB: mark interface down */
+		bsd_ctrl_iface(drv, 0);
+
 		wpa_driver_bsd_set_wpa_internal(drv, drv->prev_wpa,
 						drv->prev_privacy);