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 (os_get_random(&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 *) os_strdup("hostapd");
88
data->serverid_len = os_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 struct wpabuf * eap_sake_build_msg(struct eap_sake_data *data,
104
u8 id, size_t length, u8 subtype)
106
struct eap_sake_hdr *sake;
110
plen = sizeof(struct eap_sake_hdr) + length;
112
msg = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_SAKE, plen,
113
EAP_CODE_REQUEST, id);
115
wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to allocate memory "
120
sake = wpabuf_put(msg, sizeof(*sake));
121
sake->version = EAP_SAKE_VERSION;
122
sake->session_id = data->session_id;
123
sake->subtype = subtype;
129
static struct wpabuf * eap_sake_build_identity(struct eap_sm *sm,
130
struct eap_sake_data *data,
136
wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Identity");
140
plen += 2 + data->serverid_len;
141
msg = eap_sake_build_msg(data, id, plen, EAP_SAKE_SUBTYPE_IDENTITY);
143
data->state = FAILURE;
147
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_PERM_ID_REQ");
148
eap_sake_add_attr(msg, EAP_SAKE_AT_PERM_ID_REQ, NULL, 2);
150
if (data->serverid) {
151
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
152
eap_sake_add_attr(msg, EAP_SAKE_AT_SERVERID,
153
data->serverid, data->serverid_len);
160
static struct wpabuf * eap_sake_build_challenge(struct eap_sm *sm,
161
struct eap_sake_data *data,
167
wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Challenge");
169
if (os_get_random(data->rand_s, EAP_SAKE_RAND_LEN)) {
170
wpa_printf(MSG_ERROR, "EAP-SAKE: Failed to get random data");
171
data->state = FAILURE;
174
wpa_hexdump(MSG_MSGDUMP, "EAP-SAKE: RAND_S (server rand)",
175
data->rand_s, EAP_SAKE_RAND_LEN);
177
plen = 2 + EAP_SAKE_RAND_LEN;
179
plen += 2 + data->serverid_len;
180
msg = eap_sake_build_msg(data, id, plen, EAP_SAKE_SUBTYPE_CHALLENGE);
182
data->state = FAILURE;
186
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_RAND_S");
187
eap_sake_add_attr(msg, EAP_SAKE_AT_RAND_S,
188
data->rand_s, EAP_SAKE_RAND_LEN);
190
if (data->serverid) {
191
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_SERVERID");
192
eap_sake_add_attr(msg, EAP_SAKE_AT_SERVERID,
193
data->serverid, data->serverid_len);
200
static struct wpabuf * eap_sake_build_confirm(struct eap_sm *sm,
201
struct eap_sake_data *data,
207
wpa_printf(MSG_DEBUG, "EAP-SAKE: Request/Confirm");
209
msg = eap_sake_build_msg(data, id, 2 + EAP_SAKE_MIC_LEN,
210
EAP_SAKE_SUBTYPE_CONFIRM);
212
data->state = FAILURE;
216
wpa_printf(MSG_DEBUG, "EAP-SAKE: * AT_MIC_S");
217
wpabuf_put_u8(msg, EAP_SAKE_AT_MIC_S);
218
wpabuf_put_u8(msg, 2 + EAP_SAKE_MIC_LEN);
219
mic = wpabuf_put(msg, EAP_SAKE_MIC_LEN);
220
if (eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
221
data->serverid, data->serverid_len,
222
data->peerid, data->peerid_len, 0,
223
wpabuf_head(msg), wpabuf_len(msg), mic, mic))
225
wpa_printf(MSG_INFO, "EAP-SAKE: Failed to compute MIC");
226
data->state = FAILURE;
235
static struct wpabuf * eap_sake_buildReq(struct eap_sm *sm, void *priv, u8 id)
237
struct eap_sake_data *data = priv;
239
switch (data->state) {
241
return eap_sake_build_identity(sm, data, id);
243
return eap_sake_build_challenge(sm, data, id);
245
return eap_sake_build_confirm(sm, data, id);
247
wpa_printf(MSG_DEBUG, "EAP-SAKE: Unknown state %d in buildReq",
255
static Boolean eap_sake_check(struct eap_sm *sm, void *priv,
256
struct wpabuf *respData)
258
struct eap_sake_data *data = priv;
259
struct eap_sake_hdr *resp;
261
u8 version, session_id, subtype;
264
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, respData, &len);
265
if (pos == NULL || len < sizeof(struct eap_sake_hdr)) {
266
wpa_printf(MSG_INFO, "EAP-SAKE: Invalid frame");
270
resp = (struct eap_sake_hdr *) pos;
271
version = resp->version;
272
session_id = resp->session_id;
273
subtype = resp->subtype;
275
if (version != EAP_SAKE_VERSION) {
276
wpa_printf(MSG_INFO, "EAP-SAKE: Unknown version %d", version);
280
if (session_id != data->session_id) {
281
wpa_printf(MSG_INFO, "EAP-SAKE: Session ID mismatch (%d,%d)",
282
session_id, data->session_id);
286
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received frame: subtype=%d", subtype);
288
if (data->state == IDENTITY && subtype == EAP_SAKE_SUBTYPE_IDENTITY)
291
if (data->state == CHALLENGE && subtype == EAP_SAKE_SUBTYPE_CHALLENGE)
294
if (data->state == CONFIRM && subtype == EAP_SAKE_SUBTYPE_CONFIRM)
297
if (subtype == EAP_SAKE_SUBTYPE_AUTH_REJECT)
300
wpa_printf(MSG_INFO, "EAP-SAKE: Unexpected subtype=%d in state=%d",
301
subtype, data->state);
307
static void eap_sake_process_identity(struct eap_sm *sm,
308
struct eap_sake_data *data,
309
const struct wpabuf *respData,
310
const u8 *payload, size_t payloadlen)
312
if (data->state != IDENTITY)
315
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Identity");
316
/* TODO: update identity and select new user data */
317
eap_sake_state(data, CHALLENGE);
321
static void eap_sake_process_challenge(struct eap_sm *sm,
322
struct eap_sake_data *data,
323
const struct wpabuf *respData,
324
const u8 *payload, size_t payloadlen)
326
struct eap_sake_parse_attr attr;
327
u8 mic_p[EAP_SAKE_MIC_LEN];
329
if (data->state != CHALLENGE)
332
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Challenge");
334
if (eap_sake_parse_attributes(payload, payloadlen, &attr))
337
if (!attr.rand_p || !attr.mic_p) {
338
wpa_printf(MSG_INFO, "EAP-SAKE: Response/Challenge did not "
339
"include AT_RAND_P or AT_MIC_P");
343
os_memcpy(data->rand_p, attr.rand_p, EAP_SAKE_RAND_LEN);
345
os_free(data->peerid);
347
data->peerid_len = 0;
349
data->peerid = os_malloc(attr.peerid_len);
350
if (data->peerid == NULL)
352
os_memcpy(data->peerid, attr.peerid, attr.peerid_len);
353
data->peerid_len = attr.peerid_len;
356
if (sm->user == NULL || sm->user->password == NULL ||
357
sm->user->password_len != 2 * EAP_SAKE_ROOT_SECRET_LEN) {
358
wpa_printf(MSG_INFO, "EAP-SAKE: Plaintext password with "
359
"%d-byte key not configured",
360
2 * EAP_SAKE_ROOT_SECRET_LEN);
361
data->state = FAILURE;
364
eap_sake_derive_keys(sm->user->password,
365
sm->user->password + EAP_SAKE_ROOT_SECRET_LEN,
366
data->rand_s, data->rand_p,
367
(u8 *) &data->tek, data->msk, data->emsk);
369
eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
370
data->serverid, data->serverid_len,
371
data->peerid, data->peerid_len, 1,
372
wpabuf_head(respData), wpabuf_len(respData),
374
if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
375
wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
376
eap_sake_state(data, FAILURE);
380
eap_sake_state(data, CONFIRM);
384
static void eap_sake_process_confirm(struct eap_sm *sm,
385
struct eap_sake_data *data,
386
const struct wpabuf *respData,
387
const u8 *payload, size_t payloadlen)
389
struct eap_sake_parse_attr attr;
390
u8 mic_p[EAP_SAKE_MIC_LEN];
392
if (data->state != CONFIRM)
395
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Confirm");
397
if (eap_sake_parse_attributes(payload, payloadlen, &attr))
401
wpa_printf(MSG_INFO, "EAP-SAKE: Response/Confirm did not "
406
eap_sake_compute_mic(data->tek.auth, data->rand_s, data->rand_p,
407
data->serverid, data->serverid_len,
408
data->peerid, data->peerid_len, 1,
409
wpabuf_head(respData), wpabuf_len(respData),
411
if (os_memcmp(attr.mic_p, mic_p, EAP_SAKE_MIC_LEN) != 0) {
412
wpa_printf(MSG_INFO, "EAP-SAKE: Incorrect AT_MIC_P");
413
eap_sake_state(data, FAILURE);
415
eap_sake_state(data, SUCCESS);
419
static void eap_sake_process_auth_reject(struct eap_sm *sm,
420
struct eap_sake_data *data,
421
const struct wpabuf *respData,
422
const u8 *payload, size_t payloadlen)
424
wpa_printf(MSG_DEBUG, "EAP-SAKE: Received Response/Auth-Reject");
425
eap_sake_state(data, FAILURE);
429
static void eap_sake_process(struct eap_sm *sm, void *priv,
430
struct wpabuf *respData)
432
struct eap_sake_data *data = priv;
433
struct eap_sake_hdr *resp;
438
pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_SAKE, respData, &len);
439
if (pos == NULL || len < sizeof(struct eap_sake_hdr))
442
resp = (struct eap_sake_hdr *) pos;
444
subtype = resp->subtype;
445
pos = (u8 *) (resp + 1);
447
wpa_hexdump(MSG_DEBUG, "EAP-SAKE: Received attributes",
451
case EAP_SAKE_SUBTYPE_IDENTITY:
452
eap_sake_process_identity(sm, data, respData, pos, end - pos);
454
case EAP_SAKE_SUBTYPE_CHALLENGE:
455
eap_sake_process_challenge(sm, data, respData, pos, end - pos);
457
case EAP_SAKE_SUBTYPE_CONFIRM:
458
eap_sake_process_confirm(sm, data, respData, pos, end - pos);
460
case EAP_SAKE_SUBTYPE_AUTH_REJECT:
461
eap_sake_process_auth_reject(sm, data, respData, pos,
468
static Boolean eap_sake_isDone(struct eap_sm *sm, void *priv)
470
struct eap_sake_data *data = priv;
471
return data->state == SUCCESS || data->state == FAILURE;
475
static u8 * eap_sake_getKey(struct eap_sm *sm, void *priv, size_t *len)
477
struct eap_sake_data *data = priv;
480
if (data->state != SUCCESS)
483
key = os_malloc(EAP_MSK_LEN);
486
os_memcpy(key, data->msk, EAP_MSK_LEN);
493
static u8 * eap_sake_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
495
struct eap_sake_data *data = priv;
498
if (data->state != SUCCESS)
501
key = os_malloc(EAP_EMSK_LEN);
504
os_memcpy(key, data->emsk, EAP_EMSK_LEN);
511
static Boolean eap_sake_isSuccess(struct eap_sm *sm, void *priv)
513
struct eap_sake_data *data = priv;
514
return data->state == SUCCESS;
518
int eap_server_sake_register(void)
520
struct eap_method *eap;
523
eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
524
EAP_VENDOR_IETF, EAP_TYPE_SAKE, "SAKE");
528
eap->init = eap_sake_init;
529
eap->reset = eap_sake_reset;
530
eap->buildReq = eap_sake_buildReq;
531
eap->check = eap_sake_check;
532
eap->process = eap_sake_process;
533
eap->isDone = eap_sake_isDone;
534
eap->getKey = eap_sake_getKey;
535
eap->isSuccess = eap_sake_isSuccess;
536
eap->get_emsk = eap_sake_get_emsk;
538
ret = eap_server_method_register(eap);
540
eap_server_method_free(eap);