2 * Wi-Fi Protected Setup - attribute building
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/aes_wrap.h"
19 #include "crypto/crypto.h"
20 #include "crypto/dh_group5.h"
21 #include "crypto/sha256.h"
25 int wps_build_public_key(struct wps_data *wps, struct wpabuf *msg)
27 struct wpabuf *pubkey;
29 wpa_printf(MSG_DEBUG, "WPS: * Public Key");
30 wpabuf_free(wps->dh_privkey);
31 if (wps->dev_pw_id != DEV_PW_DEFAULT && wps->wps->dh_privkey) {
32 wpa_printf(MSG_DEBUG, "WPS: Using pre-configured DH keys");
33 wps->dh_privkey = wpabuf_dup(wps->wps->dh_privkey);
34 wps->dh_ctx = wps->wps->dh_ctx;
35 wps->wps->dh_ctx = NULL;
36 pubkey = wpabuf_dup(wps->wps->dh_pubkey);
38 wpa_printf(MSG_DEBUG, "WPS: Generate new DH keys");
39 wps->dh_privkey = NULL;
40 dh5_free(wps->dh_ctx);
41 wps->dh_ctx = dh5_init(&wps->dh_privkey, &pubkey);
42 pubkey = wpabuf_zeropad(pubkey, 192);
44 if (wps->dh_ctx == NULL || wps->dh_privkey == NULL || pubkey == NULL) {
45 wpa_printf(MSG_DEBUG, "WPS: Failed to initialize "
46 "Diffie-Hellman handshake");
50 wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH Private Key", wps->dh_privkey);
51 wpa_hexdump_buf(MSG_DEBUG, "WPS: DH own Public Key", pubkey);
53 wpabuf_put_be16(msg, ATTR_PUBLIC_KEY);
54 wpabuf_put_be16(msg, wpabuf_len(pubkey));
55 wpabuf_put_buf(msg, pubkey);
58 wpabuf_free(wps->dh_pubkey_r);
59 wps->dh_pubkey_r = pubkey;
61 wpabuf_free(wps->dh_pubkey_e);
62 wps->dh_pubkey_e = pubkey;
69 int wps_build_req_type(struct wpabuf *msg, enum wps_request_type type)
71 wpa_printf(MSG_DEBUG, "WPS: * Request Type");
72 wpabuf_put_be16(msg, ATTR_REQUEST_TYPE);
73 wpabuf_put_be16(msg, 1);
74 wpabuf_put_u8(msg, type);
79 int wps_build_resp_type(struct wpabuf *msg, enum wps_response_type type)
81 wpa_printf(MSG_DEBUG, "WPS: * Response Type (%d)", type);
82 wpabuf_put_be16(msg, ATTR_RESPONSE_TYPE);
83 wpabuf_put_be16(msg, 1);
84 wpabuf_put_u8(msg, type);
89 int wps_build_config_methods(struct wpabuf *msg, u16 methods)
91 wpa_printf(MSG_DEBUG, "WPS: * Config Methods (%x)", methods);
92 wpabuf_put_be16(msg, ATTR_CONFIG_METHODS);
93 wpabuf_put_be16(msg, 2);
94 wpabuf_put_be16(msg, methods);
99 int wps_build_uuid_e(struct wpabuf *msg, const u8 *uuid)
101 wpa_printf(MSG_DEBUG, "WPS: * UUID-E");
102 wpabuf_put_be16(msg, ATTR_UUID_E);
103 wpabuf_put_be16(msg, WPS_UUID_LEN);
104 wpabuf_put_data(msg, uuid, WPS_UUID_LEN);
109 int wps_build_dev_password_id(struct wpabuf *msg, u16 id)
111 wpa_printf(MSG_DEBUG, "WPS: * Device Password ID (%d)", id);
112 wpabuf_put_be16(msg, ATTR_DEV_PASSWORD_ID);
113 wpabuf_put_be16(msg, 2);
114 wpabuf_put_be16(msg, id);
119 int wps_build_config_error(struct wpabuf *msg, u16 err)
121 wpa_printf(MSG_DEBUG, "WPS: * Configuration Error (%d)", err);
122 wpabuf_put_be16(msg, ATTR_CONFIG_ERROR);
123 wpabuf_put_be16(msg, 2);
124 wpabuf_put_be16(msg, err);
129 int wps_build_authenticator(struct wps_data *wps, struct wpabuf *msg)
131 u8 hash[SHA256_MAC_LEN];
135 if (wps->last_msg == NULL) {
136 wpa_printf(MSG_DEBUG, "WPS: Last message not available for "
137 "building authenticator");
141 /* Authenticator = HMAC-SHA256_AuthKey(M_prev || M_curr*)
142 * (M_curr* is M_curr without the Authenticator attribute)
144 addr[0] = wpabuf_head(wps->last_msg);
145 len[0] = wpabuf_len(wps->last_msg);
146 addr[1] = wpabuf_head(msg);
147 len[1] = wpabuf_len(msg);
148 hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 2, addr, len, hash);
150 wpa_printf(MSG_DEBUG, "WPS: * Authenticator");
151 wpabuf_put_be16(msg, ATTR_AUTHENTICATOR);
152 wpabuf_put_be16(msg, WPS_AUTHENTICATOR_LEN);
153 wpabuf_put_data(msg, hash, WPS_AUTHENTICATOR_LEN);
159 int wps_build_version(struct wpabuf *msg)
162 * Note: This attribute is deprecated and set to hardcoded 0x10 for
163 * backwards compatibility reasons. The real version negotiation is
164 * done with Version2.
166 wpa_printf(MSG_DEBUG, "WPS: * Version (hardcoded 0x10)");
167 wpabuf_put_be16(msg, ATTR_VERSION);
168 wpabuf_put_be16(msg, 1);
169 wpabuf_put_u8(msg, 0x10);
174 int wps_build_version2(struct wpabuf *msg)
176 wpa_printf(MSG_DEBUG, "WPS: * Version2 (0x%x)", WPS_VERSION);
177 wpabuf_put_be16(msg, ATTR_VERSION2);
178 wpabuf_put_be16(msg, 1);
179 wpabuf_put_u8(msg, WPS_VERSION);
184 int wps_build_msg_type(struct wpabuf *msg, enum wps_msg_type msg_type)
186 wpa_printf(MSG_DEBUG, "WPS: * Message Type (%d)", msg_type);
187 wpabuf_put_be16(msg, ATTR_MSG_TYPE);
188 wpabuf_put_be16(msg, 1);
189 wpabuf_put_u8(msg, msg_type);
194 int wps_build_enrollee_nonce(struct wps_data *wps, struct wpabuf *msg)
196 wpa_printf(MSG_DEBUG, "WPS: * Enrollee Nonce");
197 wpabuf_put_be16(msg, ATTR_ENROLLEE_NONCE);
198 wpabuf_put_be16(msg, WPS_NONCE_LEN);
199 wpabuf_put_data(msg, wps->nonce_e, WPS_NONCE_LEN);
204 int wps_build_registrar_nonce(struct wps_data *wps, struct wpabuf *msg)
206 wpa_printf(MSG_DEBUG, "WPS: * Registrar Nonce");
207 wpabuf_put_be16(msg, ATTR_REGISTRAR_NONCE);
208 wpabuf_put_be16(msg, WPS_NONCE_LEN);
209 wpabuf_put_data(msg, wps->nonce_r, WPS_NONCE_LEN);
214 int wps_build_auth_type_flags(struct wps_data *wps, struct wpabuf *msg)
216 wpa_printf(MSG_DEBUG, "WPS: * Authentication Type Flags");
217 wpabuf_put_be16(msg, ATTR_AUTH_TYPE_FLAGS);
218 wpabuf_put_be16(msg, 2);
219 wpabuf_put_be16(msg, WPS_AUTH_TYPES);
224 int wps_build_encr_type_flags(struct wps_data *wps, struct wpabuf *msg)
226 wpa_printf(MSG_DEBUG, "WPS: * Encryption Type Flags");
227 wpabuf_put_be16(msg, ATTR_ENCR_TYPE_FLAGS);
228 wpabuf_put_be16(msg, 2);
229 wpabuf_put_be16(msg, WPS_ENCR_TYPES);
234 int wps_build_conn_type_flags(struct wps_data *wps, struct wpabuf *msg)
236 wpa_printf(MSG_DEBUG, "WPS: * Connection Type Flags");
237 wpabuf_put_be16(msg, ATTR_CONN_TYPE_FLAGS);
238 wpabuf_put_be16(msg, 1);
239 wpabuf_put_u8(msg, WPS_CONN_ESS);
244 int wps_build_assoc_state(struct wps_data *wps, struct wpabuf *msg)
246 wpa_printf(MSG_DEBUG, "WPS: * Association State");
247 wpabuf_put_be16(msg, ATTR_ASSOC_STATE);
248 wpabuf_put_be16(msg, 2);
249 wpabuf_put_be16(msg, WPS_ASSOC_NOT_ASSOC);
254 int wps_build_key_wrap_auth(struct wps_data *wps, struct wpabuf *msg)
256 u8 hash[SHA256_MAC_LEN];
258 wpa_printf(MSG_DEBUG, "WPS: * Key Wrap Authenticator");
259 hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, wpabuf_head(msg),
260 wpabuf_len(msg), hash);
262 wpabuf_put_be16(msg, ATTR_KEY_WRAP_AUTH);
263 wpabuf_put_be16(msg, WPS_KWA_LEN);
264 wpabuf_put_data(msg, hash, WPS_KWA_LEN);
269 int wps_build_encr_settings(struct wps_data *wps, struct wpabuf *msg,
270 struct wpabuf *plain)
273 const size_t block_size = 16;
276 wpa_printf(MSG_DEBUG, "WPS: * Encrypted Settings");
278 /* PKCS#5 v2.0 pad */
279 pad_len = block_size - wpabuf_len(plain) % block_size;
280 os_memset(wpabuf_put(plain, pad_len), pad_len, pad_len);
282 wpabuf_put_be16(msg, ATTR_ENCR_SETTINGS);
283 wpabuf_put_be16(msg, block_size + wpabuf_len(plain));
285 iv = wpabuf_put(msg, block_size);
286 if (os_get_random(iv, block_size) < 0)
289 data = wpabuf_put(msg, 0);
290 wpabuf_put_buf(msg, plain);
291 if (aes_128_cbc_encrypt(wps->keywrapkey, iv, data, wpabuf_len(plain)))
298 #ifdef CONFIG_WPS_OOB
299 int wps_build_oob_dev_password(struct wpabuf *msg, struct wps_context *wps)
303 u8 pubkey_hash[WPS_HASH_LEN];
304 u8 dev_password_bin[WPS_OOB_DEVICE_PASSWORD_LEN];
306 wpa_printf(MSG_DEBUG, "WPS: * OOB Device Password");
308 addr[0] = wpabuf_head(wps->dh_pubkey);
309 hash_len = wpabuf_len(wps->dh_pubkey);
310 sha256_vector(1, addr, &hash_len, pubkey_hash);
312 if (os_get_random((u8 *) &wps->oob_dev_pw_id, sizeof(u16)) < 0) {
313 wpa_printf(MSG_ERROR, "WPS: device password id "
317 wps->oob_dev_pw_id |= 0x0010;
319 if (os_get_random(dev_password_bin, WPS_OOB_DEVICE_PASSWORD_LEN) < 0) {
320 wpa_printf(MSG_ERROR, "WPS: OOB device password "
325 wpabuf_put_be16(msg, ATTR_OOB_DEVICE_PASSWORD);
326 wpabuf_put_be16(msg, WPS_OOB_DEVICE_PASSWORD_ATTR_LEN);
327 wpabuf_put_data(msg, pubkey_hash, WPS_OOB_PUBKEY_HASH_LEN);
328 wpabuf_put_be16(msg, wps->oob_dev_pw_id);
329 wpabuf_put_data(msg, dev_password_bin, WPS_OOB_DEVICE_PASSWORD_LEN);
331 wpa_snprintf_hex_uppercase(
332 wpabuf_put(wps->oob_conf.dev_password,
333 wpabuf_size(wps->oob_conf.dev_password)),
334 wpabuf_size(wps->oob_conf.dev_password),
335 dev_password_bin, WPS_OOB_DEVICE_PASSWORD_LEN);
339 #endif /* CONFIG_WPS_OOB */
342 int wps_build_req_to_enroll(struct wpabuf *msg)
344 wpa_printf(MSG_DEBUG, "WPS: * Request to Enroll (1)");
345 wpabuf_put_be16(msg, ATTR_REQUEST_TO_ENROLL);
346 wpabuf_put_be16(msg, 1);
347 wpabuf_put_u8(msg, 1);