2
* hostapd / EAP-SAKE (RFC 4763) server
3
* Copyright (c) 2006-2007, 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 "eap_server/eap_i.h"
19
#include "eap_common/eap_sake_common.h"
22
struct eap_sake_data {
23
enum { IDENTITY, CHALLENGE, CONFIRM, SUCCESS, FAILURE } state;
24
u8 rand_s[EAP_SAKE_RAND_LEN];
25
u8 rand_p[EAP_SAKE_RAND_LEN];
27
u8 auth[EAP_SAKE_TEK_AUTH_LEN];
28
u8 cipher[EAP_SAKE_TEK_CIPHER_LEN];
31
u8 emsk[EAP_EMSK_LEN];
40
static const char * eap_sake_state_txt(int state)
59
static void eap_sake_state(struct eap_sake_data *data, int state)
61
wpa_printf(MSG_DEBUG, "EAP-SAKE: %s -> %s",
62
eap_sake_state_txt(data->state),
63
eap_sake_state_txt(state));
68
static void * eap_sake_init(struct eap_sm *sm)
70
struct eap_sake_data *data;
72
data = os_zalloc(sizeof(*data));
75
data->state = CHALLENGE;
77
if (hostapd_get_rand(&data->session_id, 1)) {
78
wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
82
wpa_printf(MSG_DEBUG, "EAP-SAKE: Initialized Session ID %d",
85
/* TODO: add support for configuring SERVERID */
86
data->serverid = (u8 *) strdup("hostapd");
88
data->serverid_len = strlen((char *) data->serverid);
94
static void eap_sake_reset(struct eap_sm *sm, void *priv)
96
struct eap_sake_data *data = priv;
97
os_free(data->serverid);
98
os_free(data->peerid);
103
static u8 * eap_sake_build_msg(struct eap_sake_data *data, u8 **payload,
104
int id, size_t *length, u8 subtype)
106
struct eap_sake_hdr *req;
109
*length += sizeof(struct eap_sake_hdr);
111
msg = os_zalloc(*length);
113
wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to allocate memory "
118
req = (struct eap_sake_hdr *) msg;
119
req->code = EAP_CODE_REQUEST;
120
req->identifier = id;
121
req->length = host_to_be16((u16) *length);
122
req->type = EAP_TYPE_SAKE;
123
req->version = EAP_SAKE_VERSION;
124
req->session_id = data->session_id;
125
req->subtype = subtype;
126
*payload = (u8 *) (req + 1);
132
static u8 * eap_sake_build_identity(struct eap_sm *sm,
133
struct eap_sake_data *data,
134
int id, size_t *reqDataLen)
138
wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Identity");
142
*reqDataLen += 2 + data->serverid_len;
143
msg = eap_sake_build_msg(data, &pos, id, reqDataLen,
144
EAP_SAKE_SUBTYPE_IDENTITY);
146
data->state = FAILURE;
150
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PERM_ID_REQ");
151
*pos++ = EAP_SAKE_AT_PERM_ID_REQ;
156
if (data->serverid) {
157
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
158
*pos++ = EAP_SAKE_AT_SERVERID;
159
*pos++ = 2 + data->serverid_len;
160
os_memcpy(pos, data->serverid, data->serverid_len);
167
static u8 * eap_sake_build_challenge(struct eap_sm *sm,
168
struct eap_sake_data *data,
169
int id, size_t *reqDataLen)
173
wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Challenge");
175
if (hostapd_get_rand(data->rand_s, EAP_SAKE_RAND_LEN)) {
176
wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
177
data->state = FAILURE;
180
wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
181
data->rand_s, EAP_SAKE_RAND_LEN);
183
*reqDataLen = 2 + EAP_SAKE_RAND_LEN;
185
*reqDataLen += 2 + data->serverid_len;
186
msg = eap_sake_build_msg(data, &pos, id, reqDataLen,
187
EAP_SAKE_SUBTYPE_CHALLENGE);
189
data->state = FAILURE;
193
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_S");
194
*pos++ = EAP_SAKE_AT_RAND_S;
195
*pos++ = 2 + EAP_SAKE_RAND_LEN;
196
os_memcpy(pos, data->rand_s, EAP_SAKE_RAND_LEN);
197
pos += EAP_SAKE_RAND_LEN;
199
if (data->serverid) {
200
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
201
*pos++ = EAP_SAKE_AT_SERVERID;
202
*pos++ = 2 + data->serverid_len;
203
os_memcpy(pos, data->serverid, data->serverid_len);
210
static u8 * eap_sake_build_confirm(struct eap_sm *sm,
211
struct eap_sake_data *data,
212
int id, size_t *reqDataLen)
216
wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Confirm");
218
*reqDataLen = 2 + EAP_SAKE_MIC_LEN;
219
msg = eap_sake_build_msg(data, &pos, id, reqDataLen,
220
EAP_SAKE_SUBTYPE_CONFIRM);
222
data->state = FAILURE;
226
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_S");
227
*pos++ = EAP_SAKE_AT_MIC_S;
228
*pos++ = 2 + EAP_SAKE_MIC_LEN;
229
if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
230
data->serverid, data->serverid_len,
231
data->peerid, data->peerid_len, 0,
232
msg, *reqDataLen, pos, pos)) {
233
wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
234
data->state = FAILURE;
243
static u8 * eap_sake_buildReq(struct eap_sm *sm, void *priv, int id,
246
struct eap_sake_data *data = priv;
248
switch (data->state) {
250
return eap_sake_build_identity(sm, data, id, reqDataLen);
252
return eap_sake_build_challenge(sm, data, id, reqDataLen);
254
return eap_sake_build_confirm(sm, data, id, reqDataLen);
256
wpa_printf(MSG_DEBUG, "EAP-SAKE: Unknown state %d in buildReq",
264
static Boolean eap_sake_check(struct eap_sm *sm, void *priv,
265
u8 *respData, size_t respDataLen)
267
struct eap_sake_data *data = priv;
268
struct eap_sake_hdr *resp;
270
u8 version, session_id, subtype;
272
resp = (struct eap_sake_hdr *) respData;
273
if (respDataLen < sizeof(*resp) ||
274
resp->type != EAP_TYPE_SAKE ||
275
(len = be_to_host16(resp->length)) > respDataLen ||
276
len < sizeof(*resp)) {
277
wpa_printf(MSG_INFO, "EAP-SAKE: Invalid frame");
280
version = resp->version;
281
session_id = resp->session_id;
282
subtype = resp->subtype;
284
if (version != EAP_SAKE_VERSION) {
285
wpa_printf(MSG_INFO, "EAP-SAKE: Unknown version %d", version);
289
if (session_id != data->session_id) {
290
wpa_printf(MSG_INFO, "EAP-SAKE: Session ID mismatch (%d,%d)",
291
session_id, data->session_id);
295
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype=%d", subtype);
297
if (data->state == IDENTITY && subtype == EAP_SAKE_SUBTYPE_IDENTITY)
300
if (data->state == CHALLENGE && subtype == EAP_SAKE_SUBTYPE_CHALLENGE)
303
if (data->state == CONFIRM && subtype == EAP_SAKE_SUBTYPE_CONFIRM)
306
if (subtype == EAP_SAKE_SUBTYPE_AUTH_REJECT)
309
wpa_printf(MSG_INFO, "EAP-SAKE: Unexpected subtype=%d in state=%d",
310
subtype, data->state);
316
static void eap_sake_process_identity(struct eap_sm *sm,
317
struct eap_sake_data *data,
318
u8 *respData, size_t respDataLen,
319
u8 *payload, size_t payloadlen)
321
if (data->state != IDENTITY)
324
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Identity");
325
/* TODO: update identity and select new user data */
326
eap_sake_state(data, CHALLENGE);
330
static void eap_sake_process_challenge(struct eap_sm *sm,
331
struct eap_sake_data *data,
332
u8 *respData, size_t respDataLen,
333
u8 *payload, size_t payloadlen)
335
struct eap_sake_parse_attr attr;
336
u8 mic_p[EAP_SAKE_MIC_LEN];
338
if (data->state != CHALLENGE)
341
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Challenge");
343
if (eap_sake_parse_attributes(payload, payloadlen, &attr))
346
if (!attr.rand_p || !attr.mic_p) {
347
wpa_printf(MSG_INFO, "EAP-SAKE: Response/Challenge did not "
348
"include AT_RAND_P or AT_MIC_P");
352
os_memcpy(data->rand_p, attr.rand_p, EAP_SAKE_RAND_LEN);
354
os_free(data->peerid);
356
data->peerid_len = 0;
358
data->peerid = os_malloc(attr.peerid_len);
359
if (data->peerid == NULL)
361
os_memcpy(data->peerid, attr.peerid, attr.peerid_len);
362
data->peerid_len = attr.peerid_len;
365
if (sm->user == NULL || sm->user->password == NULL ||
366
sm->user->password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
367
wpa_printf(MSG_INFO, "EAP-SAKE: Plaintext password with "
368
"%d-byte key not configured",
369
2 * EAP_SAKE_ROOT_SECRET_LEN);
370
data->state = FAILURE;
373
eap_sake_derive_keys(sm->user->password,
374
sm->user->password + EAP_SAKE_ROOT_SECRET_LEN,
375
data->rand_s, data->rand_p,
376
(u8 *) &data->tek, data->msk, data->emsk);
378
eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
379
data->serverid, data->serverid_len,
380
data->peerid, data->peerid_len, 1,
381
respData, respDataLen, attr.mic_p, mic_p);
382
if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
383
wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
384
eap_sake_state(data, FAILURE);
388
eap_sake_state(data, CONFIRM);
392
static void eap_sake_process_confirm(struct eap_sm *sm,
393
struct eap_sake_data *data,
394
u8 *respData, size_t respDataLen,
395
u8 *payload, size_t payloadlen)
397
struct eap_sake_parse_attr attr;
398
u8 mic_p[EAP_SAKE_MIC_LEN];
400
if (data->state != CONFIRM)
403
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Confirm");
405
if (eap_sake_parse_attributes(payload, payloadlen, &attr))
409
wpa_printf(MSG_INFO, "EAP-SAKE: Response/Confirm did not "
414
eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
415
data->serverid, data->serverid_len,
416
data->peerid, data->peerid_len, 1,
417
respData, respDataLen, attr.mic_p, mic_p);
418
if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
419
wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
420
eap_sake_state(data, FAILURE);
422
eap_sake_state(data, SUCCESS);
426
static void eap_sake_process_auth_reject(struct eap_sm *sm,
427
struct eap_sake_data *data,
428
u8 *respData, size_t respDataLen,
429
u8 *payload, size_t payloadlen)
431
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Auth-Reject");
432
eap_sake_state(data, FAILURE);
436
static void eap_sake_process(struct eap_sm *sm, void *priv,
437
u8 *respData, size_t respDataLen)
439
struct eap_sake_data *data = priv;
440
struct eap_sake_hdr *resp;
441
u8 subtype, *pos, *end;
443
resp = (struct eap_sake_hdr *) respData;
444
subtype = resp->subtype;
445
pos = (u8 *) (resp + 1);
446
end = respData + be_to_host16(resp->length);
448
wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
452
case EAP_SAKE_SUBTYPE_IDENTITY:
453
eap_sake_process_identity(sm, data, respData, respDataLen, pos,
456
case EAP_SAKE_SUBTYPE_CHALLENGE:
457
eap_sake_process_challenge(sm, data, respData, respDataLen,
460
case EAP_SAKE_SUBTYPE_CONFIRM:
461
eap_sake_process_confirm(sm, data, respData, respDataLen, pos,
464
case EAP_SAKE_SUBTYPE_AUTH_REJECT:
465
eap_sake_process_auth_reject(sm, data, respData, respDataLen,
472
static Boolean eap_sake_isDone(struct eap_sm *sm, void *priv)
474
struct eap_sake_data *data = priv;
475
return data->state == SUCCESS || data->state == FAILURE;
479
static u8 * eap_sake_getKey(struct eap_sm *sm, void *priv, size_t *len)
481
struct eap_sake_data *data = priv;
484
if (data->state != SUCCESS)
487
key = os_malloc(EAP_MSK_LEN);
490
os_memcpy(key, data->msk, EAP_MSK_LEN);
497
static u8 * eap_sake_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
499
struct eap_sake_data *data = priv;
502
if (data->state != SUCCESS)
505
key = os_malloc(EAP_EMSK_LEN);
508
os_memcpy(key, data->emsk, EAP_EMSK_LEN);
515
static Boolean eap_sake_isSuccess(struct eap_sm *sm, void *priv)
517
struct eap_sake_data *data = priv;
518
return data->state == SUCCESS;
522
int eap_server_sake_register(void)
524
struct eap_method *eap;
527
eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
528
EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
532
eap->init = eap_sake_init;
533
eap->reset = eap_sake_reset;
534
eap->buildReq = eap_sake_buildReq;
535
eap->check = eap_sake_check;
536
eap->process = eap_sake_process;
537
eap->isDone = eap_sake_isDone;
538
eap->getKey = eap_sake_getKey;
539
eap->isSuccess = eap_sake_isSuccess;
540
eap->get_emsk = eap_sake_get_emsk;
542
ret = eap_server_method_register(eap);
544
eap_server_method_free(eap);