2 * hostapd / EAP-SAKE (RFC 4763) server
3 * Copyright (c) 2006, 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.
20 #include "eap_sake_common.h"
23 struct eap_sake_data {
24 enum { IDENTITY, CHALLENGE, CONFIRM, SUCCESS, FAILURE } state;
25 u8 rand_s[EAP_SAKE_RAND_LEN];
26 u8 rand_p[EAP_SAKE_RAND_LEN];
28 u8 auth[EAP_SAKE_TEK_AUTH_LEN];
29 u8 cipher[EAP_SAKE_TEK_CIPHER_LEN];
32 u8 emsk[EAP_EMSK_LEN];
41 static const char * eap_sake_state_txt(int state)
60 static void eap_sake_state(struct eap_sake_data *data, int state)
62 wpa_printf(MSG_DEBUG, "EAP-SAKE: %s -> %s",
63 eap_sake_state_txt(data->state),
64 eap_sake_state_txt(state));
69 static void * eap_sake_init(struct eap_sm *sm)
71 struct eap_sake_data *data;
73 data = wpa_zalloc(sizeof(*data));
76 data->state = CHALLENGE;
78 if (hostapd_get_rand(&data->session_id, 1)) {
79 wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
83 wpa_printf(MSG_DEBUG, "EAP-SAKE: Initialized Session ID %d",
86 /* TODO: add support for configuring SERVERID */
87 data->serverid = (u8 *) strdup("hostapd");
89 data->serverid_len = strlen((char *) data->serverid);
95 static void eap_sake_reset(struct eap_sm *sm, void *priv)
97 struct eap_sake_data *data = priv;
98 os_free(data->serverid);
99 os_free(data->peerid);
104 static u8 * eap_sake_build_msg(struct eap_sake_data *data, u8 **payload,
105 int id, size_t *length, u8 subtype)
107 struct eap_sake_hdr *req;
110 *length += sizeof(struct eap_sake_hdr);
112 msg = wpa_zalloc(*length);
114 wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to allocate memory "
119 req = (struct eap_sake_hdr *) msg;
120 req->code = EAP_CODE_REQUEST;
121 req->identifier = id;
122 req->length = htons((u16) *length);
123 req->type = EAP_TYPE_SAKE;
124 req->version = EAP_SAKE_VERSION;
125 req->session_id = data->session_id;
126 req->subtype = subtype;
127 *payload = (u8 *) (req + 1);
133 static u8 * eap_sake_build_identity(struct eap_sm *sm,
134 struct eap_sake_data *data,
135 int id, size_t *reqDataLen)
139 wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Identity");
143 *reqDataLen += 2 + data->serverid_len;
144 msg = eap_sake_build_msg(data, &pos, id, reqDataLen,
145 EAP_SAKE_SUBTYPE_IDENTITY);
147 data->state = FAILURE;
151 wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PERM_ID_REQ");
152 *pos++ = EAP_SAKE_AT_PERM_ID_REQ;
157 if (data->serverid) {
158 wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
159 *pos++ = EAP_SAKE_AT_SERVERID;
160 *pos++ = 2 + data->serverid_len;
161 os_memcpy(pos, data->serverid, data->serverid_len);
168 static u8 * eap_sake_build_challenge(struct eap_sm *sm,
169 struct eap_sake_data *data,
170 int id, size_t *reqDataLen)
174 wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Challenge");
176 if (hostapd_get_rand(data->rand_s, EAP_SAKE_RAND_LEN)) {
177 wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
178 data->state = FAILURE;
181 wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
182 data->rand_s, EAP_SAKE_RAND_LEN);
184 *reqDataLen = 2 + EAP_SAKE_RAND_LEN;
186 *reqDataLen += 2 + data->serverid_len;
187 msg = eap_sake_build_msg(data, &pos, id, reqDataLen,
188 EAP_SAKE_SUBTYPE_CHALLENGE);
190 data->state = FAILURE;
194 wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_S");
195 *pos++ = EAP_SAKE_AT_RAND_S;
196 *pos++ = 2 + EAP_SAKE_RAND_LEN;
197 os_memcpy(pos, data->rand_s, EAP_SAKE_RAND_LEN);
198 pos += EAP_SAKE_RAND_LEN;
200 if (data->serverid) {
201 wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
202 *pos++ = EAP_SAKE_AT_SERVERID;
203 *pos++ = 2 + data->serverid_len;
204 os_memcpy(pos, data->serverid, data->serverid_len);
211 static u8 * eap_sake_build_confirm(struct eap_sm *sm,
212 struct eap_sake_data *data,
213 int id, size_t *reqDataLen)
217 wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Confirm");
219 *reqDataLen = 2 + EAP_SAKE_MIC_LEN;
220 msg = eap_sake_build_msg(data, &pos, id, reqDataLen,
221 EAP_SAKE_SUBTYPE_CONFIRM);
223 data->state = FAILURE;
227 wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_S");
228 *pos++ = EAP_SAKE_AT_MIC_S;
229 *pos++ = 2 + EAP_SAKE_MIC_LEN;
230 if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
231 data->serverid, data->serverid_len,
232 data->peerid, data->peerid_len, 0,
233 msg, *reqDataLen, pos, pos)) {
234 wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
235 data->state = FAILURE;
244 static u8 * eap_sake_buildReq(struct eap_sm *sm, void *priv, int id,
247 struct eap_sake_data *data = priv;
249 switch (data->state) {
251 return eap_sake_build_identity(sm, data, id, reqDataLen);
253 return eap_sake_build_challenge(sm, data, id, reqDataLen);
255 return eap_sake_build_confirm(sm, data, id, reqDataLen);
257 wpa_printf(MSG_DEBUG, "EAP-SAKE: Unknown state %d in buildReq",
265 static Boolean eap_sake_check(struct eap_sm *sm, void *priv,
266 u8 *respData, size_t respDataLen)
268 struct eap_sake_data *data = priv;
269 struct eap_sake_hdr *resp;
271 u8 version, session_id, subtype;
273 resp = (struct eap_sake_hdr *) respData;
274 if (respDataLen < sizeof(*resp) ||
275 resp->type != EAP_TYPE_SAKE ||
276 (len = ntohs(resp->length)) > respDataLen ||
277 len < sizeof(*resp)) {
278 wpa_printf(MSG_INFO, "EAP-SAKE: Invalid frame");
281 version = resp->version;
282 session_id = resp->session_id;
283 subtype = resp->subtype;
285 if (version != EAP_SAKE_VERSION) {
286 wpa_printf(MSG_INFO, "EAP-SAKE: Unknown version %d", version);
290 if (session_id != data->session_id) {
291 wpa_printf(MSG_INFO, "EAP-SAKE: Session ID mismatch (%d,%d)",
292 session_id, data->session_id);
296 wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype=%d", subtype);
298 if (data->state == IDENTITY && subtype == EAP_SAKE_SUBTYPE_IDENTITY)
301 if (data->state == CHALLENGE && subtype == EAP_SAKE_SUBTYPE_CHALLENGE)
304 if (data->state == CONFIRM && subtype == EAP_SAKE_SUBTYPE_CONFIRM)
307 if (subtype == EAP_SAKE_SUBTYPE_AUTH_REJECT)
310 wpa_printf(MSG_INFO, "EAP-SAKE: Unexpected subtype=%d in state=%d",
311 subtype, data->state);
317 static void eap_sake_process_identity(struct eap_sm *sm,
318 struct eap_sake_data *data,
319 u8 *respData, size_t respDataLen,
320 u8 *payload, size_t payloadlen)
322 if (data->state != IDENTITY)
325 wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Identity");
326 /* TODO: update identity and select new user data */
327 eap_sake_state(data, CHALLENGE);
331 static void eap_sake_process_challenge(struct eap_sm *sm,
332 struct eap_sake_data *data,
333 u8 *respData, size_t respDataLen,
334 u8 *payload, size_t payloadlen)
336 struct eap_sake_parse_attr attr;
337 u8 mic_p[EAP_SAKE_MIC_LEN];
339 if (data->state != CHALLENGE)
342 wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Challenge");
344 if (eap_sake_parse_attributes(payload, payloadlen, &attr))
347 if (!attr.rand_p || !attr.mic_p) {
348 wpa_printf(MSG_INFO, "EAP-SAKE: Response/Challenge did not "
349 "include AT_RAND_P or AT_MIC_P");
353 os_memcpy(data->rand_p, attr.rand_p, EAP_SAKE_RAND_LEN);
355 os_free(data->peerid);
357 data->peerid_len = 0;
359 data->peerid = os_malloc(attr.peerid_len);
360 if (data->peerid == NULL)
362 os_memcpy(data->peerid, attr.peerid, attr.peerid_len);
363 data->peerid_len = attr.peerid_len;
366 if (sm->user == NULL || sm->user->password == NULL ||
367 sm->user->password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
368 wpa_printf(MSG_INFO, "EAP-SAKE: Plaintext password with "
369 "%d-byte key not configured",
370 2 * EAP_SAKE_ROOT_SECRET_LEN);
371 data->state = FAILURE;
374 eap_sake_derive_keys(sm->user->password,
375 sm->user->password + EAP_SAKE_ROOT_SECRET_LEN,
376 data->rand_s, data->rand_p,
377 (u8 *) &data->tek, data->msk, data->emsk);
379 eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
380 data->serverid, data->serverid_len,
381 data->peerid, data->peerid_len, 1,
382 respData, respDataLen, attr.mic_p, mic_p);
383 if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
384 wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
385 eap_sake_state(data, FAILURE);
389 eap_sake_state(data, CONFIRM);
393 static void eap_sake_process_confirm(struct eap_sm *sm,
394 struct eap_sake_data *data,
395 u8 *respData, size_t respDataLen,
396 u8 *payload, size_t payloadlen)
398 struct eap_sake_parse_attr attr;
399 u8 mic_p[EAP_SAKE_MIC_LEN];
401 if (data->state != CONFIRM)
404 wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Confirm");
406 if (eap_sake_parse_attributes(payload, payloadlen, &attr))
410 wpa_printf(MSG_INFO, "EAP-SAKE: Response/Confirm did not "
415 eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
416 data->serverid, data->serverid_len,
417 data->peerid, data->peerid_len, 1,
418 respData, respDataLen, attr.mic_p, mic_p);
419 if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
420 wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
421 eap_sake_state(data, FAILURE);
423 eap_sake_state(data, SUCCESS);
427 static void eap_sake_process_auth_reject(struct eap_sm *sm,
428 struct eap_sake_data *data,
429 u8 *respData, size_t respDataLen,
430 u8 *payload, size_t payloadlen)
432 wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Auth-Reject");
433 eap_sake_state(data, FAILURE);
437 static void eap_sake_process(struct eap_sm *sm, void *priv,
438 u8 *respData, size_t respDataLen)
440 struct eap_sake_data *data = priv;
441 struct eap_sake_hdr *resp;
442 u8 subtype, *pos, *end;
444 resp = (struct eap_sake_hdr *) respData;
445 subtype = resp->subtype;
446 pos = (u8 *) (resp + 1);
447 end = respData + ntohs(resp->length);
449 wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
453 case EAP_SAKE_SUBTYPE_IDENTITY:
454 eap_sake_process_identity(sm, data, respData, respDataLen, pos,
457 case EAP_SAKE_SUBTYPE_CHALLENGE:
458 eap_sake_process_challenge(sm, data, respData, respDataLen,
461 case EAP_SAKE_SUBTYPE_CONFIRM:
462 eap_sake_process_confirm(sm, data, respData, respDataLen, pos,
465 case EAP_SAKE_SUBTYPE_AUTH_REJECT:
466 eap_sake_process_auth_reject(sm, data, respData, respDataLen,
473 static Boolean eap_sake_isDone(struct eap_sm *sm, void *priv)
475 struct eap_sake_data *data = priv;
476 return data->state == SUCCESS || data->state == FAILURE;
480 static u8 * eap_sake_getKey(struct eap_sm *sm, void *priv, size_t *len)
482 struct eap_sake_data *data = priv;
485 if (data->state != SUCCESS)
488 key = os_malloc(EAP_MSK_LEN);
491 os_memcpy(key, data->msk, EAP_MSK_LEN);
498 static u8 * eap_sake_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
500 struct eap_sake_data *data = priv;
503 if (data->state != SUCCESS)
506 key = os_malloc(EAP_EMSK_LEN);
509 os_memcpy(key, data->emsk, EAP_EMSK_LEN);
516 static Boolean eap_sake_isSuccess(struct eap_sm *sm, void *priv)
518 struct eap_sake_data *data = priv;
519 return data->state == SUCCESS;
523 int eap_server_sake_register(void)
525 struct eap_method *eap;
528 eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
529 EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
533 eap->init = eap_sake_init;
534 eap->reset = eap_sake_reset;
535 eap->buildReq = eap_sake_buildReq;
536 eap->check = eap_sake_check;
537 eap->process = eap_sake_process;
538 eap->isDone = eap_sake_isDone;
539 eap->getKey = eap_sake_getKey;
540 eap->isSuccess = eap_sake_isSuccess;
541 eap->get_emsk = eap_sake_get_emsk;
543 ret = eap_server_method_register(eap);
545 eap_server_method_free(eap);