2 * Wi-Fi Protected Setup - attribute processing
3 * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
12 #include "crypto/sha256.h"
16 int wps_process_authenticator(struct wps_data *wps, const u8 *authenticator,
17 const struct wpabuf *msg)
19 u8 hash[SHA256_MAC_LEN];
23 if (authenticator == NULL) {
24 wpa_printf(MSG_DEBUG, "WPS: No Authenticator attribute "
29 if (wps->last_msg == NULL) {
30 wpa_printf(MSG_DEBUG, "WPS: Last message not available for "
31 "validating authenticator");
35 /* Authenticator = HMAC-SHA256_AuthKey(M_prev || M_curr*)
36 * (M_curr* is M_curr without the Authenticator attribute)
38 addr[0] = wpabuf_head(wps->last_msg);
39 len[0] = wpabuf_len(wps->last_msg);
40 addr[1] = wpabuf_head(msg);
41 len[1] = wpabuf_len(msg) - 4 - WPS_AUTHENTICATOR_LEN;
42 hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 2, addr, len, hash);
44 if (os_memcmp(hash, authenticator, WPS_AUTHENTICATOR_LEN) != 0) {
45 wpa_printf(MSG_DEBUG, "WPS: Incorrect Authenticator");
53 int wps_process_key_wrap_auth(struct wps_data *wps, struct wpabuf *msg,
54 const u8 *key_wrap_auth)
56 u8 hash[SHA256_MAC_LEN];
60 if (key_wrap_auth == NULL) {
61 wpa_printf(MSG_DEBUG, "WPS: No KWA in decrypted attribute");
65 head = wpabuf_head(msg);
66 len = wpabuf_len(msg) - 4 - WPS_KWA_LEN;
67 if (head + len != key_wrap_auth - 4) {
68 wpa_printf(MSG_DEBUG, "WPS: KWA not in the end of the "
69 "decrypted attribute");
73 hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, head, len, hash);
74 if (os_memcmp(hash, key_wrap_auth, WPS_KWA_LEN) != 0) {
75 wpa_printf(MSG_DEBUG, "WPS: Invalid KWA");
83 static int wps_process_cred_network_idx(struct wps_credential *cred,
87 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
92 wpa_printf(MSG_DEBUG, "WPS: Network Index: %d", *idx);
98 static int wps_process_cred_ssid(struct wps_credential *cred, const u8 *ssid,
102 wpa_printf(MSG_DEBUG, "WPS: Credential did not include SSID");
106 /* Remove zero-padding since some Registrar implementations seem to use
107 * hardcoded 32-octet length for this attribute */
108 while (ssid_len > 0 && ssid[ssid_len - 1] == 0)
111 wpa_hexdump_ascii(MSG_DEBUG, "WPS: SSID", ssid, ssid_len);
112 if (ssid_len <= sizeof(cred->ssid)) {
113 os_memcpy(cred->ssid, ssid, ssid_len);
114 cred->ssid_len = ssid_len;
121 static int wps_process_cred_auth_type(struct wps_credential *cred,
124 if (auth_type == NULL) {
125 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
126 "Authentication Type");
130 cred->auth_type = WPA_GET_BE16(auth_type);
131 wpa_printf(MSG_DEBUG, "WPS: Authentication Type: 0x%x",
138 static int wps_process_cred_encr_type(struct wps_credential *cred,
141 if (encr_type == NULL) {
142 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
147 cred->encr_type = WPA_GET_BE16(encr_type);
148 wpa_printf(MSG_DEBUG, "WPS: Encryption Type: 0x%x",
155 static int wps_process_cred_network_key_idx(struct wps_credential *cred,
159 return 0; /* optional attribute */
161 wpa_printf(MSG_DEBUG, "WPS: Network Key Index: %d", *key_idx);
162 cred->key_idx = *key_idx;
168 static int wps_process_cred_network_key(struct wps_credential *cred,
169 const u8 *key, size_t key_len)
172 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
174 if (cred->auth_type == WPS_AUTH_OPEN &&
175 cred->encr_type == WPS_ENCR_NONE) {
176 wpa_printf(MSG_DEBUG, "WPS: Workaround - Allow "
177 "missing mandatory Network Key attribute "
184 wpa_hexdump_key(MSG_DEBUG, "WPS: Network Key", key, key_len);
185 if (key_len <= sizeof(cred->key)) {
186 os_memcpy(cred->key, key, key_len);
187 cred->key_len = key_len;
194 static int wps_process_cred_mac_addr(struct wps_credential *cred,
197 if (mac_addr == NULL) {
198 wpa_printf(MSG_DEBUG, "WPS: Credential did not include "
203 wpa_printf(MSG_DEBUG, "WPS: MAC Address " MACSTR, MAC2STR(mac_addr));
204 os_memcpy(cred->mac_addr, mac_addr, ETH_ALEN);
210 static int wps_process_cred_eap_type(struct wps_credential *cred,
211 const u8 *eap_type, size_t eap_type_len)
213 if (eap_type == NULL)
214 return 0; /* optional attribute */
216 wpa_hexdump(MSG_DEBUG, "WPS: EAP Type", eap_type, eap_type_len);
222 static int wps_process_cred_eap_identity(struct wps_credential *cred,
226 if (identity == NULL)
227 return 0; /* optional attribute */
229 wpa_hexdump_ascii(MSG_DEBUG, "WPS: EAP Identity",
230 identity, identity_len);
236 static int wps_process_cred_key_prov_auto(struct wps_credential *cred,
237 const u8 *key_prov_auto)
239 if (key_prov_auto == NULL)
240 return 0; /* optional attribute */
242 wpa_printf(MSG_DEBUG, "WPS: Key Provided Automatically: %d",
249 static int wps_process_cred_802_1x_enabled(struct wps_credential *cred,
250 const u8 *dot1x_enabled)
252 if (dot1x_enabled == NULL)
253 return 0; /* optional attribute */
255 wpa_printf(MSG_DEBUG, "WPS: 802.1X Enabled: %d", *dot1x_enabled);
261 static int wps_process_cred_ap_channel(struct wps_credential *cred,
262 const u8 *ap_channel)
264 if (ap_channel == NULL)
265 return 0; /* optional attribute */
267 cred->ap_channel = WPA_GET_BE16(ap_channel);
268 wpa_printf(MSG_DEBUG, "WPS: AP Channel: %u", cred->ap_channel);
274 static int wps_workaround_cred_key(struct wps_credential *cred)
276 if (cred->auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK) &&
277 cred->key_len > 8 && cred->key_len < 64 &&
278 cred->key[cred->key_len - 1] == 0) {
279 #ifdef CONFIG_WPS_STRICT
280 wpa_printf(MSG_INFO, "WPS: WPA/WPA2-Personal passphrase uses "
281 "forbidden NULL termination");
282 wpa_hexdump_ascii_key(MSG_INFO, "WPS: Network Key",
283 cred->key, cred->key_len);
285 #else /* CONFIG_WPS_STRICT */
287 * A deployed external registrar is known to encode ASCII
288 * passphrases incorrectly. Remove the extra NULL termination
289 * to fix the encoding.
291 wpa_printf(MSG_DEBUG, "WPS: Workaround - remove NULL "
292 "termination from ASCII passphrase");
294 #endif /* CONFIG_WPS_STRICT */
300 int wps_process_cred(struct wps_parse_attr *attr,
301 struct wps_credential *cred)
303 wpa_printf(MSG_DEBUG, "WPS: Process Credential");
305 /* TODO: support multiple Network Keys */
306 if (wps_process_cred_network_idx(cred, attr->network_idx) ||
307 wps_process_cred_ssid(cred, attr->ssid, attr->ssid_len) ||
308 wps_process_cred_auth_type(cred, attr->auth_type) ||
309 wps_process_cred_encr_type(cred, attr->encr_type) ||
310 wps_process_cred_network_key_idx(cred, attr->network_key_idx) ||
311 wps_process_cred_network_key(cred, attr->network_key,
312 attr->network_key_len) ||
313 wps_process_cred_mac_addr(cred, attr->mac_addr) ||
314 wps_process_cred_eap_type(cred, attr->eap_type,
315 attr->eap_type_len) ||
316 wps_process_cred_eap_identity(cred, attr->eap_identity,
317 attr->eap_identity_len) ||
318 wps_process_cred_key_prov_auto(cred, attr->key_prov_auto) ||
319 wps_process_cred_802_1x_enabled(cred, attr->dot1x_enabled) ||
320 wps_process_cred_ap_channel(cred, attr->ap_channel))
323 return wps_workaround_cred_key(cred);
327 int wps_process_ap_settings(struct wps_parse_attr *attr,
328 struct wps_credential *cred)
330 wpa_printf(MSG_DEBUG, "WPS: Processing AP Settings");
331 os_memset(cred, 0, sizeof(*cred));
332 /* TODO: optional attributes New Password and Device Password ID */
333 if (wps_process_cred_ssid(cred, attr->ssid, attr->ssid_len) ||
334 wps_process_cred_auth_type(cred, attr->auth_type) ||
335 wps_process_cred_encr_type(cred, attr->encr_type) ||
336 wps_process_cred_network_key_idx(cred, attr->network_key_idx) ||
337 wps_process_cred_network_key(cred, attr->network_key,
338 attr->network_key_len) ||
339 wps_process_cred_mac_addr(cred, attr->mac_addr))
342 return wps_workaround_cred_key(cred);