WPS NFC: Process new style handover select

The new WPS connection handover select includes Registrar public key
hash instead of credential. Use the new information to start
abbreviated WPS handshake instead of configuring a new network directly
from the old Credential-from-NFC design.

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

src/eap_peer/eap_wsc.c

@@ -210,6 +210,15 @@ static void * eap_wsc_init(struct eap_sm *sm)
 			cfg.pbc = 1;
 	}
 
+	pos = os_strstr(phase1, "dev_pw_id=");
+	if (pos) {
+		u16 id = atoi(pos + 10);
+		if (id == DEV_PW_NFC_CONNECTION_HANDOVER)
+			nfc = 1;
+		if (cfg.pin || id == DEV_PW_NFC_CONNECTION_HANDOVER)
+			cfg.dev_pw_id = id;
+	}
+
 	if (cfg.pin == NULL && !cfg.pbc && !nfc) {
 		wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
 			   "configuration data");
@@ -217,10 +226,6 @@ static void * eap_wsc_init(struct eap_sm *sm)
 		return NULL;
 	}
 
-	pos = os_strstr(phase1, "dev_pw_id=");
-	if (pos && cfg.pin)
-		cfg.dev_pw_id = atoi(pos + 10);
-
 	pos = os_strstr(phase1, " pkhash=");
 	if (pos) {
 		size_t len;

wpa_supplicant/wps_supplicant.c

@@ -1120,13 +1120,18 @@ static int wpas_wps_start_dev_pw(struct wpa_supplicant *wpa_s, const u8 *bssid,
 	if (pin)
 		os_snprintf(val, sizeof(val), "\"pin=%s dev_pw_id=%u%s\"",
 			    pin, dev_pw_id, hash);
-	else {
+	else if (pin == NULL && dev_pw_id == DEV_PW_NFC_CONNECTION_HANDOVER) {
+		os_snprintf(val, sizeof(val), "\"dev_pw_id=%u%s\"",
+			    dev_pw_id, hash);
+	} else {
 		rpin = wps_generate_pin();
 		os_snprintf(val, sizeof(val), "\"pin=%08d dev_pw_id=%u%s\"",
 			    rpin, dev_pw_id, hash);
 	}
-	if (wpa_config_set(ssid, "phase1", val, 0) < 0)
+	if (wpa_config_set(ssid, "phase1", val, 0) < 0) {
+		wpa_printf(MSG_DEBUG, "WPS: Failed to set phase1 '%s'", val);
 		return -1;
+	}
 	if (wpa_s->wps_fragment_size)
 		ssid->eap.fragment_size = wpa_s->wps_fragment_size;
 	eloop_register_timeout(WPS_PBC_WALK_TIME, 0, wpas_wps_timeout,
@@ -2106,15 +2111,23 @@ int wpas_wps_start_nfc(struct wpa_supplicant *wpa_s, const u8 *bssid,
 	struct wps_context *wps = wpa_s->wps;
 	char pw[32 * 2 + 1];
 
-	if (dev_pw == NULL) {
+	if (dev_pw_id != DEV_PW_NFC_CONNECTION_HANDOVER && dev_pw == NULL) {
 		dev_pw = wpa_s->conf->wps_nfc_dev_pw;
 		dev_pw_id = wpa_s->conf->wps_nfc_dev_pw_id;
 	}
 
 	if (wpa_s->conf->wps_nfc_dh_pubkey == NULL ||
-	    wpa_s->conf->wps_nfc_dh_privkey == NULL ||
-	    dev_pw == NULL)
+	    wpa_s->conf->wps_nfc_dh_privkey == NULL) {
+		wpa_printf(MSG_DEBUG, "WPS: Missing DH params - "
+			   "cannot start NFC-triggered connection");
+		return -1;
+	}
+
+	if (dev_pw_id != DEV_PW_NFC_CONNECTION_HANDOVER && dev_pw == NULL) {
+		wpa_printf(MSG_DEBUG, "WPS: Missing Device Password (id=%u) - "
+			   "cannot start NFC-triggered connection", dev_pw_id);
 		return -1;
+	}
 
 	dh5_free(wps->dh_ctx);
 	wpabuf_free(wps->dh_pubkey);
@@ -2127,6 +2140,7 @@ int wpas_wps_start_nfc(struct wpa_supplicant *wpa_s, const u8 *bssid,
 		wps->dh_pubkey = NULL;
 		wpabuf_free(wps->dh_privkey);
 		wps->dh_privkey = NULL;
+		wpa_printf(MSG_DEBUG, "WPS: Failed to get DH priv/pub key");
 		return -1;
 	}
 	wps->dh_ctx = dh5_init_fixed(wps->dh_privkey, wps->dh_pubkey);
@@ -2135,13 +2149,18 @@ int wpas_wps_start_nfc(struct wpa_supplicant *wpa_s, const u8 *bssid,
 		wps->dh_pubkey = NULL;
 		wpabuf_free(wps->dh_privkey);
 		wps->dh_privkey = NULL;
+		wpa_printf(MSG_DEBUG, "WPS: Failed to initialize DH context");
 		return -1;
 	}
 
-	wpa_snprintf_hex_uppercase(pw, sizeof(pw),
-				   wpabuf_head(dev_pw), wpabuf_len(dev_pw));
-	return wpas_wps_start_dev_pw(wpa_s, bssid, pw, p2p_group, dev_pw_id,
-				     peer_pubkey_hash, ssid, ssid_len);
+	if (dev_pw) {
+		wpa_snprintf_hex_uppercase(pw, sizeof(pw),
+					   wpabuf_head(dev_pw),
+					   wpabuf_len(dev_pw));
+	}
+	return wpas_wps_start_dev_pw(wpa_s, bssid, dev_pw ? pw : NULL,
+				     p2p_group, dev_pw_id, peer_pubkey_hash,
+				     ssid, ssid_len);
 }
 
 
@@ -2354,17 +2373,86 @@ int wpas_wps_nfc_rx_handover_sel(struct wpa_supplicant *wpa_s,
 				 const struct wpabuf *data)
 {
 	struct wpabuf *wps;
-	int ret;
+	int ret = -1;
+	u16 wsc_len;
+	const u8 *pos;
+	struct wpabuf msg;
+	struct wps_parse_attr attr;
+	u16 dev_pw_id;
 
 	wps = ndef_parse_wifi(data);
 	if (wps == NULL)
 		return -1;
 	wpa_printf(MSG_DEBUG, "WPS: Received application/vnd.wfa.wsc "
 		   "payload from NFC connection handover");
-	wpa_hexdump_buf_key(MSG_DEBUG, "WPS: NFC payload", wps);
-	ret = wpas_wps_nfc_tag_process(wpa_s, wps);
+	wpa_hexdump_buf(MSG_DEBUG, "WPS: NFC payload", wps);
+	if (wpabuf_len(wps) < 2) {
+		wpa_printf(MSG_DEBUG, "WPS: Too short Wi-Fi Handover Select "
+			   "Message");
+		goto out;
+	}
+	pos = wpabuf_head(wps);
+	wsc_len = WPA_GET_BE16(pos);
+	if (wsc_len > wpabuf_len(wps) - 2) {
+		wpa_printf(MSG_DEBUG, "WPS: Invalid WSC attribute length (%u) "
+			   "in Wi-Fi Handover Select Message", wsc_len);
+		goto out;
+	}
+	pos += 2;
+
+	wpa_hexdump(MSG_DEBUG,
+		    "WPS: WSC attributes in Wi-Fi Handover Select Message",
+		    pos, wsc_len);
+	if (wsc_len < wpabuf_len(wps) - 2) {
+		wpa_hexdump(MSG_DEBUG,
+			    "WPS: Ignore extra data after WSC attributes",
+			    pos + wsc_len, wpabuf_len(wps) - 2 - wsc_len);
+	}
+
+	wpabuf_set(&msg, pos, wsc_len);
+	ret = wps_parse_msg(&msg, &attr);
+	if (ret < 0) {
+		wpa_printf(MSG_DEBUG, "WPS: Could not parse WSC attributes in "
+			   "Wi-Fi Handover Select Message");
+		goto out;
+	}
+
+	if (attr.oob_dev_password == NULL ||
+	    attr.oob_dev_password_len < WPS_OOB_PUBKEY_HASH_LEN + 2) {
+		wpa_printf(MSG_DEBUG, "WPS: No Out-of-Band Device Password "
+			   "included in Wi-Fi Handover Select Message");
+		ret = -1;
+		goto out;
+	}
+
+	if (attr.ssid == NULL) {
+		wpa_printf(MSG_DEBUG, "WPS: No SSID included in Wi-Fi Handover "
+			   "Select Message");
+		ret = -1;
+		goto out;
+	}
+
+	wpa_hexdump_ascii(MSG_DEBUG, "WPS: SSID", attr.ssid, attr.ssid_len);
+
+	wpa_hexdump(MSG_DEBUG, "WPS: Out-of-Band Device Password",
+		    attr.oob_dev_password, attr.oob_dev_password_len);
+	dev_pw_id = WPA_GET_BE16(attr.oob_dev_password +
+				 WPS_OOB_PUBKEY_HASH_LEN);
+	if (dev_pw_id != DEV_PW_NFC_CONNECTION_HANDOVER) {
+		wpa_printf(MSG_DEBUG, "WPS: Unexpected OOB Device Password ID "
+			   "%u in Wi-Fi Handover Select Message", dev_pw_id);
+		ret = -1;
+		goto out;
+	}
+	wpa_hexdump(MSG_DEBUG, "WPS: AP Public Key hash",
+		    attr.oob_dev_password, WPS_OOB_PUBKEY_HASH_LEN);
+
+	ret = wpas_wps_start_nfc(wpa_s, NULL, NULL, dev_pw_id, 0,
+				 attr.oob_dev_password,
+				 attr.ssid, attr.ssid_len);
+
+out:
 	wpabuf_free(wps);
-
 	return ret;
 }