hostapd: Add support for testing Probe Response frame elements

Add support for additional (vendor) elements to be added
to only Probe Response frames, for testing.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

hostapd/config_file.c

@@ -4516,6 +4516,9 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 		bss->eapol_m3_no_encrypt = atoi(pos);
 	} else if (os_strcmp(buf, "test_assoc_comeback_type") == 0) {
 		bss->test_assoc_comeback_type = atoi(pos);
+	} else if (os_strcmp(buf, "presp_elements") == 0) {
+		if (parse_wpabuf_hex(line, buf, &bss->presp_elements, pos))
+			return 1;
 #endif /* CONFIG_TESTING_OPTIONS */
 #ifdef CONFIG_SAE
 	} else if (os_strcmp(buf, "sae_password") == 0) {

hostapd/hostapd.conf

@@ -3216,6 +3216,13 @@ own_ip_addr=127.0.0.1
 # attempt (wpa_pairwise_update_count). This will trigger a timeout on all
 # previous attempts and thus delays the frame. (testing only)
 #delay_eapol_tx=0
+#
+# Additional elements for Probe Response frames.
+# This parameter can be used to add additional element(s) to the end of the
+# Probe Response frames. The format for these element(s) is a hexdump of the
+# raw information elements (id+len+payload for one or more elements).
+# These elements are added after the 'vendor_elements'.
+#presp_elements=
 
 ##### Multiple BSSID support ##################################################
 #

src/ap/ap_config.c

@@ -967,6 +967,7 @@ void hostapd_config_free_bss(struct hostapd_bss_config *conf)
 	wpabuf_free(conf->igtk_rsc_override);
 	wpabuf_free(conf->eapol_m1_elements);
 	wpabuf_free(conf->eapol_m3_elements);
+	wpabuf_free(conf->presp_elements);
 #endif /* CONFIG_TESTING_OPTIONS */
 
 	os_free(conf->no_probe_resp_if_seen_on);

src/ap/ap_config.h

@@ -709,6 +709,7 @@ struct hostapd_bss_config {
 	struct wpabuf *eapol_m3_elements;
 	bool eapol_m3_no_encrypt;
 	int test_assoc_comeback_type;
+	struct wpabuf *presp_elements;
 
 #ifdef CONFIG_IEEE80211BE
 	u16 eht_oper_puncturing_override;

src/ap/ap_drv_ops.c

@@ -208,6 +208,9 @@ int hostapd_build_ap_extra_ies(struct hostapd_data *hapd,
 
 	add_buf(&beacon, hapd->conf->vendor_elements);
 	add_buf(&proberesp, hapd->conf->vendor_elements);
+#ifdef CONFIG_TESTING_OPTIONS
+	add_buf(&proberesp, hapd->conf->presp_elements);
+#endif /* CONFIG_TESTING_OPTIONS */
 	add_buf(&assocresp, hapd->conf->assocresp_elements);
 
 	*beacon_ret = beacon;

src/ap/beacon.c

@@ -649,6 +649,10 @@ static size_t hostapd_probe_resp_elems_len(struct hostapd_data *hapd,
 #endif /* CONFIG_FST */
 	if (hapd->conf->vendor_elements)
 		buflen += wpabuf_len(hapd->conf->vendor_elements);
+#ifdef CONFIG_TESTING_OPTIONS
+	if (hapd->conf->presp_elements)
+		buflen += wpabuf_len(hapd->conf->presp_elements);
+#endif /* CONFIG_TESTING_OPTIONS */
 	if (hapd->conf->vendor_vht) {
 		buflen += 5 + 2 + sizeof(struct ieee80211_vht_capabilities) +
 			2 + sizeof(struct ieee80211_vht_operation);
@@ -885,6 +889,14 @@ static u8 * hostapd_probe_resp_fill_elems(struct hostapd_data *hapd,
 		pos += wpabuf_len(hapd->conf->vendor_elements);
 	}
 
+#ifdef CONFIG_TESTING_OPTIONS
+	if (hapd->conf->presp_elements) {
+		os_memcpy(pos, wpabuf_head(hapd->conf->presp_elements),
+			  wpabuf_len(hapd->conf->presp_elements));
+		pos += wpabuf_len(hapd->conf->presp_elements);
+	}
+#endif /* CONFIG_TESTING_OPTIONS */
+
 	return pos;
 }