WPS: Add a workaround for PBC session overlap detection

Some deployed station implementations implement WPS incorrectly and
end up causing PBC session overlap issues by indicating active PBC
mode in a scan after the WPS provisioning step. Work around this by
ignoring active PBC indication in a Probe Request from a station that
completed PBC provisioning during the last five seconds.

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>

src/wps/wps_registrar.c

@@ -180,6 +180,9 @@ struct wps_registrar {
 	u8 authorized_macs_union[WPS_MAX_AUTHORIZED_MACS][ETH_ALEN];
 
 	u8 p2p_dev_addr[ETH_ALEN];
+
+	u8 pbc_ignore_uuid[WPS_UUID_LEN];
+	struct os_time pbc_ignore_start;
 };
 
 
@@ -1030,6 +1033,8 @@ void wps_registrar_complete(struct wps_registrar *registrar, const u8 *uuid_e,
 		wps_registrar_remove_pbc_session(registrar,
 						 uuid_e, NULL);
 		wps_registrar_pbc_completed(registrar);
+		os_get_time(&registrar->pbc_ignore_start);
+		os_memcpy(registrar->pbc_ignore_uuid, uuid_e, WPS_UUID_LEN);
 	} else {
 		wps_registrar_pin_completed(registrar);
 	}
@@ -1076,6 +1081,7 @@ void wps_registrar_probe_req_rx(struct wps_registrar *reg, const u8 *addr,
 				int p2p_wildcard)
 {
 	struct wps_parse_attr attr;
+	int skip_add = 0;
 
 	wpa_hexdump_buf(MSG_MSGDUMP,
 			"WPS: Probe Request with WPS data received",
@@ -1127,7 +1133,24 @@ void wps_registrar_probe_req_rx(struct wps_registrar *reg, const u8 *addr,
 	wpa_hexdump(MSG_DEBUG, "WPS: UUID-E from Probe Request", attr.uuid_e,
 		    WPS_UUID_LEN);
 
-	wps_registrar_add_pbc_session(reg, addr, attr.uuid_e);
+#ifdef WPS_WORKAROUNDS
+	if (reg->pbc_ignore_start.sec &&
+	    os_memcmp(attr.uuid_e, reg->pbc_ignore_uuid, WPS_UUID_LEN) == 0) {
+		struct os_time now, dur;
+		os_get_time(&now);
+		os_time_sub(&now, &reg->pbc_ignore_start, &dur);
+		if (dur.sec >= 0 && dur.sec < 5) {
+			wpa_printf(MSG_DEBUG, "WPS: Ignore PBC activation "
+				   "based on Probe Request from the Enrollee "
+				   "that just completed PBC provisioning");
+			skip_add = 1;
+		} else
+			reg->pbc_ignore_start.sec = 0;
+	}
+#endif /* WPS_WORKAROUNDS */
+
+	if (!skip_add)
+		wps_registrar_add_pbc_session(reg, addr, attr.uuid_e);
 	if (wps_registrar_pbc_overlap(reg, addr, attr.uuid_e)) {
 		wpa_printf(MSG_DEBUG, "WPS: PBC session overlap detected");
 		reg->force_pbc_overlap = 1;
@@ -3157,6 +3180,9 @@ static enum wps_process_res wps_process_wsc_done(struct wps_data *wps,
 						 wps->uuid_e,
 						 wps->p2p_dev_addr);
 		wps_registrar_pbc_completed(wps->wps->registrar);
+		os_get_time(&wps->wps->registrar->pbc_ignore_start);
+		os_memcpy(wps->wps->registrar->pbc_ignore_uuid, wps->uuid_e,
+			  WPS_UUID_LEN);
 	} else {
 		wps_registrar_pin_completed(wps->wps->registrar);
 	}