2 * Wi-Fi Protected Setup - attribute processing
3 * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * Alternatively, this software may be distributed under the terms of BSD
12 * See README and COPYING for more details.
18 #include "crypto/sha256.h"
22 int wps_process_authenticator(struct wps_data *wps, const u8 *authenticator,
23 const struct wpabuf *msg)
25 u8 hash[SHA256_MAC_LEN];
29 if (authenticator == NULL) {
30 wpa_printf(MSG_DEBUG, "WPS: No Authenticator attribute "
35 if (wps->last_msg == NULL) {
36 wpa_printf(MSG_DEBUG, "WPS: Last message not available for "
37 "validating authenticator");
41 /* Authenticator = HMAC-SHA256_AuthKey(M_prev || M_curr*)
42 * (M_curr* is M_curr without the Authenticator attribute)
44 addr[0] = wpabuf_head(wps->last_msg);
45 len[0] = wpabuf_len(wps->last_msg);
46 addr[1] = wpabuf_head(msg);
47 len[1] = wpabuf_len(msg) - 4 - WPS_AUTHENTICATOR_LEN;
48 hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 2, addr, len, hash);
50 if (os_memcmp(hash, authenticator, WPS_AUTHENTICATOR_LEN) != 0) {
51 wpa_printf(MSG_DEBUG, "WPS: Incorrect Authenticator");
59 int wps_process_key_wrap_auth(struct wps_data *wps, struct wpabuf *msg,
60 const u8 *key_wrap_auth)
62 u8 hash[SHA256_MAC_LEN];
66 if (key_wrap_auth == NULL) {
67 wpa_printf(MSG_DEBUG, "WPS: No KWA in decrypted attribute");
71 head = wpabuf_head(msg);
72 len = wpabuf_len(msg) - 4 - WPS_KWA_LEN;
73 if (head + len != key_wrap_auth - 4) {
74 wpa_printf(MSG_DEBUG, "WPS: KWA not in the end of the "
75 "decrypted attribute");
79 hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, head, len, hash);
80 if (os_memcmp(hash, key_wrap_auth, WPS_KWA_LEN) != 0) {
81 wpa_printf(MSG_DEBUG, "WPS: Invalid KWA");
89 static int wps_process_cred_network_idx(struct wps_credential *cred,
93 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
98 wpa_printf(MSG_DEBUG, "WPS: Network Index: %d", *idx);
104 static int wps_process_cred_ssid(struct wps_credential *cred, const u8 *ssid,
108 wpa_printf(MSG_DEBUG, "WPS: Credential did not include SSID");
112 /* Remove zero-padding since some Registrar implementations seem to use
113 * hardcoded 32-octet length for this attribute */
114 while (ssid_len > 0 && ssid[ssid_len - 1] == 0)
117 wpa_hexdump_ascii(MSG_DEBUG, "WPS: SSID", ssid, ssid_len);
118 if (ssid_len <= sizeof(cred->ssid)) {
119 os_memcpy(cred->ssid, ssid, ssid_len);
120 cred->ssid_len = ssid_len;
127 static int wps_process_cred_auth_type(struct wps_credential *cred,
130 if (auth_type == NULL) {
131 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
132 "Authentication Type");
136 cred->auth_type = WPA_GET_BE16(auth_type);
137 wpa_printf(MSG_DEBUG, "WPS: Authentication Type: 0x%x",
144 static int wps_process_cred_encr_type(struct wps_credential *cred,
147 if (encr_type == NULL) {
148 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
153 cred->encr_type = WPA_GET_BE16(encr_type);
154 wpa_printf(MSG_DEBUG, "WPS: Encryption Type: 0x%x",
161 static int wps_process_cred_network_key_idx(struct wps_credential *cred,
165 return 0; /* optional attribute */
167 wpa_printf(MSG_DEBUG, "WPS: Network Key Index: %d", *key_idx);
168 cred->key_idx = *key_idx;
174 static int wps_process_cred_network_key(struct wps_credential *cred,
175 const u8 *key, size_t key_len)
178 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
180 if (cred->auth_type == WPS_AUTH_OPEN &&
181 cred->encr_type == WPS_ENCR_NONE) {
182 wpa_printf(MSG_DEBUG, "WPS: Workaround - Allow "
183 "missing mandatory Network Key attribute "
190 wpa_hexdump_key(MSG_DEBUG, "WPS: Network Key", key, key_len);
191 if (key_len <= sizeof(cred->key)) {
192 os_memcpy(cred->key, key, key_len);
193 cred->key_len = key_len;
200 static int wps_process_cred_mac_addr(struct wps_credential *cred,
203 if (mac_addr == NULL) {
204 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
209 wpa_printf(MSG_DEBUG, "WPS: MAC Address " MACSTR, MAC2STR(mac_addr));
210 os_memcpy(cred->mac_addr, mac_addr, ETH_ALEN);
216 static int wps_process_cred_eap_type(struct wps_credential *cred,
217 const u8 *eap_type, size_t eap_type_len)
219 if (eap_type == NULL)
220 return 0; /* optional attribute */
222 wpa_hexdump(MSG_DEBUG, "WPS: EAP Type", eap_type, eap_type_len);
228 static int wps_process_cred_eap_identity(struct wps_credential *cred,
232 if (identity == NULL)
233 return 0; /* optional attribute */
235 wpa_hexdump_ascii(MSG_DEBUG, "WPS: EAP Identity",
236 identity, identity_len);
242 static int wps_process_cred_key_prov_auto(struct wps_credential *cred,
243 const u8 *key_prov_auto)
245 if (key_prov_auto == NULL)
246 return 0; /* optional attribute */
248 wpa_printf(MSG_DEBUG, "WPS: Key Provided Automatically: %d",
255 static int wps_process_cred_802_1x_enabled(struct wps_credential *cred,
256 const u8 *dot1x_enabled)
258 if (dot1x_enabled == NULL)
259 return 0; /* optional attribute */
261 wpa_printf(MSG_DEBUG, "WPS: 802.1X Enabled: %d", *dot1x_enabled);
267 static int wps_workaround_cred_key(struct wps_credential *cred)
269 if (cred->auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK) &&
270 cred->key_len > 8 && cred->key_len < 64 &&
271 cred->key[cred->key_len - 1] == 0) {
272 #ifdef CONFIG_WPS_STRICT
273 wpa_printf(MSG_INFO, "WPS: WPA/WPA2-Personal passphrase uses "
274 "forbidden NULL termination");
275 wpa_hexdump_ascii_key(MSG_INFO, "WPS: Network Key",
276 cred->key, cred->key_len);
278 #else /* CONFIG_WPS_STRICT */
280 * A deployed external registrar is known to encode ASCII
281 * passphrases incorrectly. Remove the extra NULL termination
282 * to fix the encoding.
284 wpa_printf(MSG_DEBUG, "WPS: Workaround - remove NULL "
285 "termination from ASCII passphrase");
287 #endif /* CONFIG_WPS_STRICT */
293 int wps_process_cred(struct wps_parse_attr *attr,
294 struct wps_credential *cred)
296 wpa_printf(MSG_DEBUG, "WPS: Process Credential");
298 /* TODO: support multiple Network Keys */
299 if (wps_process_cred_network_idx(cred, attr->network_idx) ||
300 wps_process_cred_ssid(cred, attr->ssid, attr->ssid_len) ||
301 wps_process_cred_auth_type(cred, attr->auth_type) ||
302 wps_process_cred_encr_type(cred, attr->encr_type) ||
303 wps_process_cred_network_key_idx(cred, attr->network_key_idx) ||
304 wps_process_cred_network_key(cred, attr->network_key,
305 attr->network_key_len) ||
306 wps_process_cred_mac_addr(cred, attr->mac_addr) ||
307 wps_process_cred_eap_type(cred, attr->eap_type,
308 attr->eap_type_len) ||
309 wps_process_cred_eap_identity(cred, attr->eap_identity,
310 attr->eap_identity_len) ||
311 wps_process_cred_key_prov_auto(cred, attr->key_prov_auto) ||
312 wps_process_cred_802_1x_enabled(cred, attr->dot1x_enabled))
315 return wps_workaround_cred_key(cred);
319 int wps_process_ap_settings(struct wps_parse_attr *attr,
320 struct wps_credential *cred)
322 wpa_printf(MSG_DEBUG, "WPS: Processing AP Settings");
323 os_memset(cred, 0, sizeof(*cred));
324 /* TODO: optional attributes New Password and Device Password ID */
325 if (wps_process_cred_ssid(cred, attr->ssid, attr->ssid_len) ||
326 wps_process_cred_auth_type(cred, attr->auth_type) ||
327 wps_process_cred_encr_type(cred, attr->encr_type) ||
328 wps_process_cred_network_key_idx(cred, attr->network_key_idx) ||
329 wps_process_cred_network_key(cred, attr->network_key,
330 attr->network_key_len) ||
331 wps_process_cred_mac_addr(cred, attr->mac_addr))
334 return wps_workaround_cred_key(cred);