Authenticator side testing functionality for EAPOL-Key Key Data field

Allow additional elements and KDEs to be added to EAPOL-Key msg 1/4 and
3/4 and allow EAPOL-Key msg 3/4 Key Data field to be not encrypted.
These are for testing purposes to enable a convenient mechanism for
testing supplicant behavior with either potential future extensions or
incorrect Authenticator behavior.

Signed-off-by: Jouni Malinen <quic_jouni@quicinc.com>

hostapd/config_file.c

@@ -4355,6 +4355,14 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 		bss->eap_skip_prot_success = atoi(pos);
 	} else if (os_strcmp(buf, "delay_eapol_tx") == 0) {
 		conf->delay_eapol_tx = atoi(pos);
+	} else if (os_strcmp(buf, "eapol_m1_elements") == 0) {
+		if (parse_wpabuf_hex(line, buf, &bss->eapol_m1_elements, pos))
+			return 1;
+	} else if (os_strcmp(buf, "eapol_m3_elements") == 0) {
+		if (parse_wpabuf_hex(line, buf, &bss->eapol_m3_elements, pos))
+			return 1;
+	} else if (os_strcmp(buf, "eapol_m3_no_encrypt") == 0) {
+		bss->eapol_m3_no_encrypt = atoi(pos);
 #endif /* CONFIG_TESTING_OPTIONS */
 #ifdef CONFIG_SAE
 	} else if (os_strcmp(buf, "sae_password") == 0) {

src/ap/ap_config.c

@@ -948,6 +948,8 @@ void hostapd_config_free_bss(struct hostapd_bss_config *conf)
 	wpabuf_free(conf->rsnxe_override_ft);
 	wpabuf_free(conf->gtk_rsc_override);
 	wpabuf_free(conf->igtk_rsc_override);
+	wpabuf_free(conf->eapol_m1_elements);
+	wpabuf_free(conf->eapol_m3_elements);
 #endif /* CONFIG_TESTING_OPTIONS */
 
 	os_free(conf->no_probe_resp_if_seen_on);

src/ap/ap_config.h

@@ -704,6 +704,9 @@ struct hostapd_bss_config {
 	unsigned int oci_freq_override_ft_assoc;
 	unsigned int oci_freq_override_fils_assoc;
 	unsigned int oci_freq_override_wnm_sleep;
+	struct wpabuf *eapol_m1_elements;
+	struct wpabuf *eapol_m3_elements;
+	bool eapol_m3_no_encrypt;
 
 #ifdef CONFIG_IEEE80211BE
 	u16 eht_oper_puncturing_override;

src/ap/wpa_auth.c

@@ -623,6 +623,17 @@ int wpa_init_keys(struct wpa_authenticator *wpa_auth)
 }
 
 
+static void wpa_auth_free_conf(struct wpa_auth_config *conf)
+{
+#ifdef CONFIG_TESTING_OPTIONS
+	wpabuf_free(conf->eapol_m1_elements);
+	conf->eapol_m1_elements = NULL;
+	wpabuf_free(conf->eapol_m3_elements);
+	conf->eapol_m3_elements = NULL;
+#endif /* CONFIG_TESTING_OPTIONS */
+}
+
+
 /**
  * wpa_deinit - Deinitialize WPA authenticator
  * @wpa_auth: Pointer to WPA authenticator data from wpa_init()
@@ -656,6 +667,7 @@ void wpa_deinit(struct wpa_authenticator *wpa_auth)
 		bin_clear_free(prev, sizeof(*prev));
 	}
 
+	wpa_auth_free_conf(&wpa_auth->conf);
 	os_free(wpa_auth);
 }
 
@@ -673,6 +685,7 @@ int wpa_reconfig(struct wpa_authenticator *wpa_auth,
 	if (!wpa_auth)
 		return 0;
 
+	wpa_auth_free_conf(&wpa_auth->conf);
 	os_memcpy(&wpa_auth->conf, conf, sizeof(*conf));
 	if (wpa_auth_gen_wpa_ie(wpa_auth)) {
 		wpa_printf(MSG_ERROR, "Could not generate WPA IE.");
@@ -2332,10 +2345,14 @@ SM_STATE(WPA_PTK, INITPSK)
 
 SM_STATE(WPA_PTK, PTKSTART)
 {
-	u8 buf[2 * (2 + RSN_SELECTOR_LEN) + PMKID_LEN + ETH_ALEN];
+	u8 *buf;
+	size_t buf_len = 2 + RSN_SELECTOR_LEN + PMKID_LEN;
 	u8 *pmkid = NULL;
 	size_t kde_len = 0;
 	u16 key_info;
+#ifdef CONFIG_TESTING_OPTIONS
+	struct wpa_auth_config *conf = &sm->wpa_auth->conf;
+#endif /* CONFIG_TESTING_OPTIONS */
 
 	SM_ENTRY_MA(WPA_PTK, PTKSTART, wpa_ptk);
 	sm->PTKRequest = false;
@@ -2350,6 +2367,19 @@ SM_STATE(WPA_PTK, PTKSTART)
 		return;
 	}
 
+#ifdef CONFIG_IEEE80211BE
+	if (sm->mld_assoc_link_id >= 0)
+		buf_len += 2 + RSN_SELECTOR_LEN + ETH_ALEN;
+#endif /* CONFIG_IEEE80211BE */
+#ifdef CONFIG_TESTING_OPTIONS
+	if (conf->eapol_m1_elements)
+		buf_len += wpabuf_len(conf->eapol_m1_elements);
+#endif /* CONFIG_TESTING_OPTIONS */
+
+	buf = os_zalloc(buf_len);
+	if (!buf)
+		return;
+
 	wpa_auth_logger(sm->wpa_auth, wpa_auth_get_spa(sm), LOGGER_DEBUG,
 			"sending 1/4 msg of 4-Way Handshake");
 	/*
@@ -2453,11 +2483,20 @@ SM_STATE(WPA_PTK, PTKSTART)
 	}
 #endif /* CONFIG_IEEE80211BE */
 
+#ifdef CONFIG_TESTING_OPTIONS
+	if (conf->eapol_m1_elements) {
+		os_memcpy(buf + kde_len, wpabuf_head(conf->eapol_m1_elements),
+			  wpabuf_len(conf->eapol_m1_elements));
+		kde_len += wpabuf_len(conf->eapol_m1_elements);
+	}
+#endif /* CONFIG_TESTING_OPTIONS */
+
 	key_info = WPA_KEY_INFO_ACK | WPA_KEY_INFO_KEY_TYPE;
 	if (sm->pairwise_set && sm->wpa != WPA_VERSION_WPA)
 		key_info |= WPA_KEY_INFO_SECURE;
 	wpa_send_eapol(sm->wpa_auth, sm, key_info, NULL,
 		       sm->ANonce, kde_len ? buf : NULL, kde_len, 0, 0);
+	os_free(buf);
 }
 
 
@@ -4260,6 +4299,11 @@ SM_STATE(WPA_PTK, PTKINITNEGOTIATING)
 
 	kde_len += wpa_auth_ml_kdes_len(sm);
 
+#ifdef CONFIG_TESTING_OPTIONS
+	if (conf->eapol_m3_elements)
+		kde_len += wpabuf_len(conf->eapol_m3_elements);
+#endif /* CONFIG_TESTING_OPTIONS */
+
 	kde = os_malloc(kde_len);
 	if (!kde)
 		goto done;
@@ -4374,6 +4418,17 @@ SM_STATE(WPA_PTK, PTKINITNEGOTIATING)
 
 	pos = wpa_auth_ml_kdes(sm, pos);
 
+#ifdef CONFIG_TESTING_OPTIONS
+	if (conf->eapol_m3_elements) {
+		os_memcpy(pos, wpabuf_head(conf->eapol_m3_elements),
+			  wpabuf_len(conf->eapol_m3_elements));
+		pos += wpabuf_len(conf->eapol_m3_elements);
+	}
+
+	if (conf->eapol_m3_no_encrypt)
+		encr = 0;
+#endif /* CONFIG_TESTING_OPTIONS */
+
 	wpa_send_eapol(sm->wpa_auth, sm,
 		       (secure ? WPA_KEY_INFO_SECURE : 0) |
 		       (wpa_mic_len(sm->wpa_key_mgmt, sm->pmk_len) ?

src/ap/wpa_auth.h

@@ -242,6 +242,9 @@ struct wpa_auth_config {
 	unsigned int igtk_rsc_override_set:1;
 	int ft_rsnxe_used;
 	bool delay_eapol_tx;
+	struct wpabuf *eapol_m1_elements;
+	struct wpabuf *eapol_m3_elements;
+	bool eapol_m3_no_encrypt;
 #endif /* CONFIG_TESTING_OPTIONS */
 	unsigned int oci_freq_override_eapol_m3;
 	unsigned int oci_freq_override_eapol_g1;

src/ap/wpa_auth_glue.c

@@ -183,6 +183,12 @@ static void hostapd_wpa_auth_conf(struct hostapd_bss_config *conf,
 	wconf->oci_freq_override_ft_assoc = conf->oci_freq_override_ft_assoc;
 	wconf->oci_freq_override_fils_assoc =
 		conf->oci_freq_override_fils_assoc;
+
+	if (conf->eapol_m1_elements)
+		wconf->eapol_m1_elements = wpabuf_dup(conf->eapol_m1_elements);
+	if (conf->eapol_m3_elements)
+		wconf->eapol_m3_elements = wpabuf_dup(conf->eapol_m3_elements);
+	wconf->eapol_m3_no_encrypt = conf->eapol_m3_no_encrypt;
 #endif /* CONFIG_TESTING_OPTIONS */
 #ifdef CONFIG_P2P
 	os_memcpy(wconf->ip_addr_go, conf->ip_addr_go, 4);