2 * hostapd / EAP-PAX (RFC 4746) server
3 * Copyright (c) 2005-2006, 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_pax_common.h"
23 * Note: only PAX_STD subprotocol is currently supported
25 * TODO: Add support with PAX_SEC with the mandatory to implement ciphersuite
26 * (HMAC_SHA1_128, IANA DH Group 14 (2048 bits), RSA-PKCS1-V1_5) and
27 * recommended ciphersuite (HMAC_SHA256_128, IANA DH Group 15 (3072 bits),
32 enum { PAX_STD_1, PAX_STD_3, SUCCESS, FAILURE } state;
35 u8 e[2 * EAP_PAX_RAND_LEN];
37 u8 x[EAP_PAX_RAND_LEN]; /* server rand */
38 u8 y[EAP_PAX_RAND_LEN]; /* client rand */
41 u8 ak[EAP_PAX_AK_LEN];
42 u8 mk[EAP_PAX_MK_LEN];
43 u8 ck[EAP_PAX_CK_LEN];
44 u8 ick[EAP_PAX_ICK_LEN];
51 static void * eap_pax_init(struct eap_sm *sm)
53 struct eap_pax_data *data;
55 data = wpa_zalloc(sizeof(*data));
58 data->state = PAX_STD_1;
60 * TODO: make this configurable once EAP_PAX_HMAC_SHA256_128 is
63 data->mac_id = EAP_PAX_MAC_HMAC_SHA1_128;
69 static void eap_pax_reset(struct eap_sm *sm, void *priv)
71 struct eap_pax_data *data = priv;
77 static u8 * eap_pax_build_std_1(struct eap_sm *sm,
78 struct eap_pax_data *data,
79 int id, size_t *reqDataLen)
81 struct eap_pax_hdr *req;
84 wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-1 (sending)");
86 if (hostapd_get_rand(data->rand.r.x, EAP_PAX_RAND_LEN)) {
87 wpa_printf(MSG_ERROR, "EAP-PAX: Failed to get random data");
88 data->state = FAILURE;
92 *reqDataLen = sizeof(*req) + 2 + EAP_PAX_RAND_LEN + EAP_PAX_ICV_LEN;
93 req = malloc(*reqDataLen);
95 wpa_printf(MSG_ERROR, "EAP-PAX: Failed to allocate memory "
97 data->state = FAILURE;
101 req->code = EAP_CODE_REQUEST;
102 req->identifier = id;
103 req->length = htons(*reqDataLen);
104 req->type = EAP_TYPE_PAX;
105 req->op_code = EAP_PAX_OP_STD_1;
107 req->mac_id = data->mac_id;
108 req->dh_group_id = EAP_PAX_DH_GROUP_NONE;
109 req->public_key_id = EAP_PAX_PUBLIC_KEY_NONE;
110 pos = (u8 *) (req + 1);
112 *pos++ = EAP_PAX_RAND_LEN;
113 memcpy(pos, data->rand.r.x, EAP_PAX_RAND_LEN);
114 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: A = X (server rand)",
115 pos, EAP_PAX_RAND_LEN);
116 pos += EAP_PAX_RAND_LEN;
118 eap_pax_mac(data->mac_id, (u8 *) "", 0,
119 (u8 *) req, *reqDataLen - EAP_PAX_ICV_LEN,
120 NULL, 0, NULL, 0, pos);
121 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN);
122 pos += EAP_PAX_ICV_LEN;
128 static u8 * eap_pax_build_std_3(struct eap_sm *sm,
129 struct eap_pax_data *data,
130 int id, size_t *reqDataLen)
132 struct eap_pax_hdr *req;
135 wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-3 (sending)");
137 *reqDataLen = sizeof(*req) + 2 + EAP_PAX_MAC_LEN + EAP_PAX_ICV_LEN;
138 req = malloc(*reqDataLen);
140 wpa_printf(MSG_ERROR, "EAP-PAX: Failed to allocate memory "
142 data->state = FAILURE;
146 req->code = EAP_CODE_REQUEST;
147 req->identifier = id;
148 req->length = htons(*reqDataLen);
149 req->type = EAP_TYPE_PAX;
150 req->op_code = EAP_PAX_OP_STD_3;
152 req->mac_id = data->mac_id;
153 req->dh_group_id = EAP_PAX_DH_GROUP_NONE;
154 req->public_key_id = EAP_PAX_PUBLIC_KEY_NONE;
155 pos = (u8 *) (req + 1);
157 *pos++ = EAP_PAX_MAC_LEN;
158 eap_pax_mac(data->mac_id, data->ck, EAP_PAX_CK_LEN,
159 data->rand.r.y, EAP_PAX_RAND_LEN,
160 (u8 *) data->cid, data->cid_len, NULL, 0, pos);
161 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: MAC_CK(B, CID)",
162 pos, EAP_PAX_MAC_LEN);
163 pos += EAP_PAX_MAC_LEN;
165 /* Optional ADE could be added here, if needed */
167 eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN,
168 (u8 *) req, *reqDataLen - EAP_PAX_ICV_LEN,
169 NULL, 0, NULL, 0, pos);
170 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN);
171 pos += EAP_PAX_ICV_LEN;
177 static u8 * eap_pax_buildReq(struct eap_sm *sm, void *priv, int id,
180 struct eap_pax_data *data = priv;
182 switch (data->state) {
184 return eap_pax_build_std_1(sm, data, id, reqDataLen);
186 return eap_pax_build_std_3(sm, data, id, reqDataLen);
188 wpa_printf(MSG_DEBUG, "EAP-PAX: Unknown state %d in buildReq",
196 static Boolean eap_pax_check(struct eap_sm *sm, void *priv,
197 u8 *respData, size_t respDataLen)
199 struct eap_pax_data *data = priv;
200 struct eap_pax_hdr *resp;
202 u8 icvbuf[EAP_PAX_ICV_LEN], *icv;
204 resp = (struct eap_pax_hdr *) respData;
205 if (respDataLen < sizeof(*resp) || resp->type != EAP_TYPE_PAX ||
206 (len = ntohs(resp->length)) > respDataLen ||
207 len < sizeof(*resp) + EAP_PAX_ICV_LEN) {
208 wpa_printf(MSG_INFO, "EAP-PAX: Invalid frame");
212 wpa_printf(MSG_DEBUG, "EAP-PAX: received frame: op_code 0x%x "
213 "flags 0x%x mac_id 0x%x dh_group_id 0x%x "
214 "public_key_id 0x%x",
215 resp->op_code, resp->flags, resp->mac_id, resp->dh_group_id,
216 resp->public_key_id);
217 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: received payload",
218 (u8 *) (resp + 1), len - sizeof(*resp) - EAP_PAX_ICV_LEN);
220 if (data->state == PAX_STD_1 &&
221 resp->op_code != EAP_PAX_OP_STD_2) {
222 wpa_printf(MSG_DEBUG, "EAP-PAX: Expected PAX_STD-2 - "
223 "ignore op %d", resp->op_code);
227 if (data->state == PAX_STD_3 &&
228 resp->op_code != EAP_PAX_OP_ACK) {
229 wpa_printf(MSG_DEBUG, "EAP-PAX: Expected PAX-ACK - "
230 "ignore op %d", resp->op_code);
234 if (resp->op_code != EAP_PAX_OP_STD_2 &&
235 resp->op_code != EAP_PAX_OP_ACK) {
236 wpa_printf(MSG_DEBUG, "EAP-PAX: Unknown op_code 0x%x",
240 if (data->mac_id != resp->mac_id) {
241 wpa_printf(MSG_DEBUG, "EAP-PAX: Expected MAC ID 0x%x, "
242 "received 0x%x", data->mac_id, resp->mac_id);
246 if (resp->dh_group_id != EAP_PAX_DH_GROUP_NONE) {
247 wpa_printf(MSG_INFO, "EAP-PAX: Expected DH Group ID 0x%x, "
248 "received 0x%x", EAP_PAX_DH_GROUP_NONE,
253 if (resp->public_key_id != EAP_PAX_PUBLIC_KEY_NONE) {
254 wpa_printf(MSG_INFO, "EAP-PAX: Expected Public Key ID 0x%x, "
255 "received 0x%x", EAP_PAX_PUBLIC_KEY_NONE,
256 resp->public_key_id);
260 if (resp->flags & EAP_PAX_FLAGS_MF) {
261 /* TODO: add support for reassembling fragments */
262 wpa_printf(MSG_INFO, "EAP-PAX: fragmentation not supported");
266 if (resp->flags & EAP_PAX_FLAGS_CE) {
267 wpa_printf(MSG_INFO, "EAP-PAX: Unexpected CE flag");
271 if (data->keys_set) {
272 if (len - sizeof(*resp) < EAP_PAX_ICV_LEN) {
273 wpa_printf(MSG_INFO, "EAP-PAX: No ICV in the packet");
276 icv = respData + len - EAP_PAX_ICV_LEN;
277 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", icv, EAP_PAX_ICV_LEN);
278 eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN,
279 respData, len - EAP_PAX_ICV_LEN, NULL, 0, NULL, 0,
281 if (memcmp(icvbuf, icv, EAP_PAX_ICV_LEN) != 0) {
282 wpa_printf(MSG_INFO, "EAP-PAX: Invalid ICV");
283 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected ICV",
284 icvbuf, EAP_PAX_ICV_LEN);
293 static void eap_pax_process_std_2(struct eap_sm *sm,
294 struct eap_pax_data *data,
295 u8 *respData, size_t respDataLen)
297 struct eap_pax_hdr *resp;
298 u8 *pos, mac[EAP_PAX_MAC_LEN], icvbuf[EAP_PAX_ICV_LEN];
302 if (data->state != PAX_STD_1)
305 wpa_printf(MSG_DEBUG, "EAP-PAX: Received PAX_STD-2");
307 resp = (struct eap_pax_hdr *) respData;
308 len = ntohs(resp->length);
309 pos = (u8 *) (resp + 1);
310 left = len - sizeof(*resp);
312 if (left < 2 + EAP_PAX_RAND_LEN ||
313 ((pos[0] << 8) | pos[1]) != EAP_PAX_RAND_LEN) {
314 wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (B)");
319 memcpy(data->rand.r.y, pos, EAP_PAX_RAND_LEN);
320 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Y (client rand)",
321 data->rand.r.y, EAP_PAX_RAND_LEN);
322 pos += EAP_PAX_RAND_LEN;
323 left -= EAP_PAX_RAND_LEN;
325 if (left < 2 || (size_t) 2 + ((pos[0] << 8) | pos[1]) > left) {
326 wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (CID)");
329 data->cid_len = (pos[0] << 8) | pos[1];
331 data->cid = malloc(data->cid_len);
332 if (data->cid == NULL) {
333 wpa_printf(MSG_INFO, "EAP-PAX: Failed to allocate memory for "
337 memcpy(data->cid, pos + 2, data->cid_len);
338 pos += 2 + data->cid_len;
339 left -= 2 + data->cid_len;
340 wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-PAX: CID",
341 (u8 *) data->cid, data->cid_len);
343 if (left < 2 + EAP_PAX_MAC_LEN ||
344 ((pos[0] << 8) | pos[1]) != EAP_PAX_MAC_LEN) {
345 wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (MAC_CK)");
350 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: MAC_CK(A, B, CID)",
351 pos, EAP_PAX_MAC_LEN);
353 if (eap_user_get(sm, (u8 *) data->cid, data->cid_len, 0) < 0) {
354 wpa_hexdump_ascii(MSG_DEBUG, "EAP-PAX: unknown CID",
355 (u8 *) data->cid, data->cid_len);
356 data->state = FAILURE;
361 i < EAP_MAX_METHODS &&
362 (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
363 sm->user->methods[i].method != EAP_TYPE_NONE);
365 if (sm->user->methods[i].vendor == EAP_VENDOR_IETF &&
366 sm->user->methods[i].method == EAP_TYPE_PAX)
370 if (i >= EAP_MAX_METHODS ||
371 sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
372 sm->user->methods[i].method != EAP_TYPE_PAX) {
373 wpa_hexdump_ascii(MSG_DEBUG,
374 "EAP-PAX: EAP-PAX not enabled for CID",
375 (u8 *) data->cid, data->cid_len);
376 data->state = FAILURE;
380 if (sm->user->password == NULL ||
381 sm->user->password_len != EAP_PAX_AK_LEN) {
382 wpa_hexdump_ascii(MSG_DEBUG, "EAP-PAX: invalid password in "
383 "user database for CID",
384 (u8 *) data->cid, data->cid_len);
385 data->state = FAILURE;
388 memcpy(data->ak, sm->user->password, EAP_PAX_AK_LEN);
390 if (eap_pax_initial_key_derivation(data->mac_id, data->ak,
391 data->rand.e, data->mk, data->ck,
393 wpa_printf(MSG_INFO, "EAP-PAX: Failed to complete initial "
395 data->state = FAILURE;
400 eap_pax_mac(data->mac_id, data->ck, EAP_PAX_CK_LEN,
401 data->rand.r.x, EAP_PAX_RAND_LEN,
402 data->rand.r.y, EAP_PAX_RAND_LEN,
403 (u8 *) data->cid, data->cid_len, mac);
404 if (memcmp(mac, pos, EAP_PAX_MAC_LEN) != 0) {
405 wpa_printf(MSG_INFO, "EAP-PAX: Invalid MAC_CK(A, B, CID) in "
407 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected MAC_CK(A, B, CID)",
408 mac, EAP_PAX_MAC_LEN);
409 data->state = FAILURE;
413 pos += EAP_PAX_MAC_LEN;
414 left -= EAP_PAX_MAC_LEN;
416 if (left < EAP_PAX_ICV_LEN) {
417 wpa_printf(MSG_INFO, "EAP-PAX: Too short ICV (%lu) in "
418 "PAX_STD-2", (unsigned long) left);
421 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN);
422 eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN,
423 respData, len - EAP_PAX_ICV_LEN, NULL, 0, NULL, 0, icvbuf);
424 if (memcmp(icvbuf, pos, EAP_PAX_ICV_LEN) != 0) {
425 wpa_printf(MSG_INFO, "EAP-PAX: Invalid ICV in PAX_STD-2");
426 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected ICV",
427 icvbuf, EAP_PAX_ICV_LEN);
430 pos += EAP_PAX_ICV_LEN;
431 left -= EAP_PAX_ICV_LEN;
434 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ignored extra payload",
438 data->state = PAX_STD_3;
442 static void eap_pax_process_ack(struct eap_sm *sm,
443 struct eap_pax_data *data,
444 u8 *respData, size_t respDataLen)
446 if (data->state != PAX_STD_3)
449 wpa_printf(MSG_DEBUG, "EAP-PAX: Received PAX-ACK - authentication "
450 "completed successfully");
451 data->state = SUCCESS;
455 static void eap_pax_process(struct eap_sm *sm, void *priv,
456 u8 *respData, size_t respDataLen)
458 struct eap_pax_data *data = priv;
459 struct eap_pax_hdr *resp;
461 if (sm->user == NULL || sm->user->password == NULL) {
462 wpa_printf(MSG_INFO, "EAP-PAX: Plaintext password not "
464 data->state = FAILURE;
468 resp = (struct eap_pax_hdr *) respData;
470 switch (resp->op_code) {
471 case EAP_PAX_OP_STD_2:
472 eap_pax_process_std_2(sm, data, respData, respDataLen);
475 eap_pax_process_ack(sm, data, respData, respDataLen);
481 static Boolean eap_pax_isDone(struct eap_sm *sm, void *priv)
483 struct eap_pax_data *data = priv;
484 return data->state == SUCCESS || data->state == FAILURE;
488 static u8 * eap_pax_getKey(struct eap_sm *sm, void *priv, size_t *len)
490 struct eap_pax_data *data = priv;
493 if (data->state != SUCCESS)
496 key = malloc(EAP_MSK_LEN);
501 eap_pax_kdf(data->mac_id, data->mk, EAP_PAX_MK_LEN,
502 "Master Session Key", data->rand.e, 2 * EAP_PAX_RAND_LEN,
509 static u8 * eap_pax_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
511 struct eap_pax_data *data = priv;
514 if (data->state != SUCCESS)
517 key = malloc(EAP_EMSK_LEN);
522 eap_pax_kdf(data->mac_id, data->mk, EAP_PAX_MK_LEN,
523 "Extended Master Session Key",
524 data->rand.e, 2 * EAP_PAX_RAND_LEN,
531 static Boolean eap_pax_isSuccess(struct eap_sm *sm, void *priv)
533 struct eap_pax_data *data = priv;
534 return data->state == SUCCESS;
538 int eap_server_pax_register(void)
540 struct eap_method *eap;
543 eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
544 EAP_VENDOR_IETF, EAP_TYPE_PAX, "PAX");
548 eap->init = eap_pax_init;
549 eap->reset = eap_pax_reset;
550 eap->buildReq = eap_pax_buildReq;
551 eap->check = eap_pax_check;
552 eap->process = eap_pax_process;
553 eap->isDone = eap_pax_isDone;
554 eap->getKey = eap_pax_getKey;
555 eap->isSuccess = eap_pax_isSuccess;
556 eap->get_emsk = eap_pax_get_emsk;
558 ret = eap_server_method_register(eap);
560 eap_server_method_free(eap);