2 * EAP peer method: EAP-PAX (RFC 4746)
3 * Copyright (c) 2005-2008, 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 "eap_common/eap_pax_common.h"
22 * Note: only PAX_STD subprotocol is currently supported
24 * TODO: Add support with PAX_SEC with the mandatory to implement ciphersuite
25 * (HMAC_SHA1_128, IANA DH Group 14 (2048 bits), RSA-PKCS1-V1_5) and
26 * recommended ciphersuite (HMAC_SHA256_128, IANA DH Group 15 (3072 bits),
31 enum { PAX_INIT
, PAX_STD_2_SENT
, PAX_DONE
} state
;
32 u8 mac_id
, dh_group_id
, public_key_id
;
34 u8 e
[2 * EAP_PAX_RAND_LEN
];
36 u8 x
[EAP_PAX_RAND_LEN
]; /* server rand */
37 u8 y
[EAP_PAX_RAND_LEN
]; /* client rand */
42 u8 ak
[EAP_PAX_AK_LEN
];
43 u8 mk
[EAP_PAX_MK_LEN
];
44 u8 ck
[EAP_PAX_CK_LEN
];
45 u8 ick
[EAP_PAX_ICK_LEN
];
49 static void eap_pax_deinit(struct eap_sm
*sm
, void *priv
);
52 static void * eap_pax_init(struct eap_sm
*sm
)
54 struct eap_pax_data
*data
;
55 const u8
*identity
, *password
;
56 size_t identity_len
, password_len
;
58 identity
= eap_get_config_identity(sm
, &identity_len
);
59 password
= eap_get_config_password(sm
, &password_len
);
60 if (!identity
|| !password
) {
61 wpa_printf(MSG_INFO
, "EAP-PAX: CID (nai) or key (password) "
66 if (password_len
!= EAP_PAX_AK_LEN
) {
67 wpa_printf(MSG_INFO
, "EAP-PAX: Invalid PSK length");
71 data
= os_zalloc(sizeof(*data
));
74 data
->state
= PAX_INIT
;
76 data
->cid
= os_malloc(identity_len
);
77 if (data
->cid
== NULL
) {
78 eap_pax_deinit(sm
, data
);
81 os_memcpy(data
->cid
, identity
, identity_len
);
82 data
->cid_len
= identity_len
;
84 os_memcpy(data
->ak
, password
, EAP_PAX_AK_LEN
);
90 static void eap_pax_deinit(struct eap_sm
*sm
, void *priv
)
92 struct eap_pax_data
*data
= priv
;
98 static struct wpabuf
* eap_pax_alloc_resp(const struct eap_pax_hdr
*req
,
99 u8 id
, u8 op_code
, size_t plen
)
102 struct eap_pax_hdr
*pax
;
104 resp
= eap_msg_alloc(EAP_VENDOR_IETF
, EAP_TYPE_PAX
,
105 sizeof(*pax
) + plen
, EAP_CODE_RESPONSE
, id
);
109 pax
= wpabuf_put(resp
, sizeof(*pax
));
110 pax
->op_code
= op_code
;
112 pax
->mac_id
= req
->mac_id
;
113 pax
->dh_group_id
= req
->dh_group_id
;
114 pax
->public_key_id
= req
->public_key_id
;
120 static struct wpabuf
* eap_pax_process_std_1(struct eap_pax_data
*data
,
121 struct eap_method_ret
*ret
, u8 id
,
122 const struct eap_pax_hdr
*req
,
130 wpa_printf(MSG_DEBUG
, "EAP-PAX: PAX_STD-1 (received)");
132 if (data
->state
!= PAX_INIT
) {
133 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-1 received in "
134 "unexpected state (%d) - ignored", data
->state
);
139 if (req
->flags
& EAP_PAX_FLAGS_CE
) {
140 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-1 with CE flag set - "
146 left
= req_plen
- sizeof(*req
);
148 if (left
< 2 + EAP_PAX_RAND_LEN
) {
149 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-1 with too short "
155 pos
= (const u8
*) (req
+ 1);
156 if (WPA_GET_BE16(pos
) != EAP_PAX_RAND_LEN
) {
157 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-1 with incorrect A "
158 "length %d (expected %d)",
159 WPA_GET_BE16(pos
), EAP_PAX_RAND_LEN
);
166 os_memcpy(data
->rand
.r
.x
, pos
, EAP_PAX_RAND_LEN
);
167 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: X (server rand)",
168 data
->rand
.r
.x
, EAP_PAX_RAND_LEN
);
169 pos
+= EAP_PAX_RAND_LEN
;
170 left
-= EAP_PAX_RAND_LEN
;
173 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: ignored extra payload",
177 if (os_get_random(data
->rand
.r
.y
, EAP_PAX_RAND_LEN
)) {
178 wpa_printf(MSG_ERROR
, "EAP-PAX: Failed to get random data");
182 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: Y (client rand)",
183 data
->rand
.r
.y
, EAP_PAX_RAND_LEN
);
185 if (eap_pax_initial_key_derivation(req
->mac_id
, data
->ak
, data
->rand
.e
,
186 data
->mk
, data
->ck
, data
->ick
) < 0)
192 wpa_printf(MSG_DEBUG
, "EAP-PAX: PAX_STD-2 (sending)");
194 plen
= 2 + EAP_PAX_RAND_LEN
+ 2 + data
->cid_len
+ 2 + EAP_PAX_MAC_LEN
+
196 resp
= eap_pax_alloc_resp(req
, id
, EAP_PAX_OP_STD_2
, plen
);
200 wpabuf_put_be16(resp
, EAP_PAX_RAND_LEN
);
201 wpabuf_put_data(resp
, data
->rand
.r
.y
, EAP_PAX_RAND_LEN
);
202 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: B = Y (client rand)",
203 data
->rand
.r
.y
, EAP_PAX_RAND_LEN
);
205 wpabuf_put_be16(resp
, data
->cid_len
);
206 wpabuf_put_data(resp
, data
->cid
, data
->cid_len
);
207 wpa_hexdump_ascii(MSG_MSGDUMP
, "EAP-PAX: CID",
208 (u8
*) data
->cid
, data
->cid_len
);
210 wpabuf_put_be16(resp
, EAP_PAX_MAC_LEN
);
211 rpos
= wpabuf_put(resp
, EAP_PAX_MAC_LEN
);
212 eap_pax_mac(req
->mac_id
, data
->ck
, EAP_PAX_CK_LEN
,
213 data
->rand
.r
.x
, EAP_PAX_RAND_LEN
,
214 data
->rand
.r
.y
, EAP_PAX_RAND_LEN
,
215 (u8
*) data
->cid
, data
->cid_len
, rpos
);
216 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: MAC_CK(A, B, CID)",
217 rpos
, EAP_PAX_MAC_LEN
);
219 /* Optional ADE could be added here, if needed */
221 rpos
= wpabuf_put(resp
, EAP_PAX_ICV_LEN
);
222 eap_pax_mac(req
->mac_id
, data
->ick
, EAP_PAX_ICK_LEN
,
223 wpabuf_head(resp
), wpabuf_len(resp
) - EAP_PAX_ICV_LEN
,
224 NULL
, 0, NULL
, 0, rpos
);
225 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: ICV", rpos
, EAP_PAX_ICV_LEN
);
227 data
->state
= PAX_STD_2_SENT
;
228 data
->mac_id
= req
->mac_id
;
229 data
->dh_group_id
= req
->dh_group_id
;
230 data
->public_key_id
= req
->public_key_id
;
236 static struct wpabuf
* eap_pax_process_std_3(struct eap_pax_data
*data
,
237 struct eap_method_ret
*ret
, u8 id
,
238 const struct eap_pax_hdr
*req
,
242 u8
*rpos
, mac
[EAP_PAX_MAC_LEN
];
246 wpa_printf(MSG_DEBUG
, "EAP-PAX: PAX_STD-3 (received)");
248 if (data
->state
!= PAX_STD_2_SENT
) {
249 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-3 received in "
250 "unexpected state (%d) - ignored", data
->state
);
255 if (req
->flags
& EAP_PAX_FLAGS_CE
) {
256 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-3 with CE flag set - "
262 left
= req_plen
- sizeof(*req
);
264 if (left
< 2 + EAP_PAX_MAC_LEN
) {
265 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-3 with too short "
271 pos
= (const u8
*) (req
+ 1);
272 if (WPA_GET_BE16(pos
) != EAP_PAX_MAC_LEN
) {
273 wpa_printf(MSG_INFO
, "EAP-PAX: PAX_STD-3 with incorrect "
274 "MAC_CK length %d (expected %d)",
275 WPA_GET_BE16(pos
), EAP_PAX_MAC_LEN
);
281 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: MAC_CK(B, CID)",
282 pos
, EAP_PAX_MAC_LEN
);
283 eap_pax_mac(data
->mac_id
, data
->ck
, EAP_PAX_CK_LEN
,
284 data
->rand
.r
.y
, EAP_PAX_RAND_LEN
,
285 (u8
*) data
->cid
, data
->cid_len
, NULL
, 0, mac
);
286 if (os_memcmp(pos
, mac
, EAP_PAX_MAC_LEN
) != 0) {
287 wpa_printf(MSG_INFO
, "EAP-PAX: Invalid MAC_CK(B, CID) "
289 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: expected MAC_CK(B, CID)",
290 mac
, EAP_PAX_MAC_LEN
);
291 ret
->methodState
= METHOD_DONE
;
292 ret
->decision
= DECISION_FAIL
;
296 pos
+= EAP_PAX_MAC_LEN
;
297 left
-= EAP_PAX_MAC_LEN
;
300 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: ignored extra payload",
304 wpa_printf(MSG_DEBUG
, "EAP-PAX: PAX-ACK (sending)");
306 resp
= eap_pax_alloc_resp(req
, id
, EAP_PAX_OP_ACK
, EAP_PAX_ICV_LEN
);
310 /* Optional ADE could be added here, if needed */
312 rpos
= wpabuf_put(resp
, EAP_PAX_ICV_LEN
);
313 eap_pax_mac(data
->mac_id
, data
->ick
, EAP_PAX_ICK_LEN
,
314 wpabuf_head(resp
), wpabuf_len(resp
) - EAP_PAX_ICV_LEN
,
315 NULL
, 0, NULL
, 0, rpos
);
316 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: ICV", rpos
, EAP_PAX_ICV_LEN
);
318 data
->state
= PAX_DONE
;
319 ret
->methodState
= METHOD_DONE
;
320 ret
->decision
= DECISION_UNCOND_SUCC
;
321 ret
->allowNotifications
= FALSE
;
327 static struct wpabuf
* eap_pax_process(struct eap_sm
*sm
, void *priv
,
328 struct eap_method_ret
*ret
,
329 const struct wpabuf
*reqData
)
331 struct eap_pax_data
*data
= priv
;
332 const struct eap_pax_hdr
*req
;
334 u8 icvbuf
[EAP_PAX_ICV_LEN
], id
;
339 pos
= eap_hdr_validate(EAP_VENDOR_IETF
, EAP_TYPE_PAX
, reqData
, &len
);
340 if (pos
== NULL
|| len
< EAP_PAX_ICV_LEN
) {
344 id
= eap_get_id(reqData
);
345 req
= (const struct eap_pax_hdr
*) pos
;
346 flen
= len
- EAP_PAX_ICV_LEN
;
347 mlen
= wpabuf_len(reqData
) - EAP_PAX_ICV_LEN
;
349 wpa_printf(MSG_DEBUG
, "EAP-PAX: received frame: op_code 0x%x "
350 "flags 0x%x mac_id 0x%x dh_group_id 0x%x "
351 "public_key_id 0x%x",
352 req
->op_code
, req
->flags
, req
->mac_id
, req
->dh_group_id
,
354 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: received payload",
355 pos
, len
- EAP_PAX_ICV_LEN
);
357 if (data
->state
!= PAX_INIT
&& data
->mac_id
!= req
->mac_id
) {
358 wpa_printf(MSG_INFO
, "EAP-PAX: MAC ID changed during "
359 "authentication (was 0x%d, is 0x%d)",
360 data
->mac_id
, req
->mac_id
);
365 if (data
->state
!= PAX_INIT
&& data
->dh_group_id
!= req
->dh_group_id
) {
366 wpa_printf(MSG_INFO
, "EAP-PAX: DH Group ID changed during "
367 "authentication (was 0x%d, is 0x%d)",
368 data
->dh_group_id
, req
->dh_group_id
);
373 if (data
->state
!= PAX_INIT
&&
374 data
->public_key_id
!= req
->public_key_id
) {
375 wpa_printf(MSG_INFO
, "EAP-PAX: Public Key ID changed during "
376 "authentication (was 0x%d, is 0x%d)",
377 data
->public_key_id
, req
->public_key_id
);
382 /* TODO: add support EAP_PAX_HMAC_SHA256_128 */
383 if (req
->mac_id
!= EAP_PAX_MAC_HMAC_SHA1_128
) {
384 wpa_printf(MSG_INFO
, "EAP-PAX: Unsupported MAC ID 0x%x",
390 if (req
->dh_group_id
!= EAP_PAX_DH_GROUP_NONE
) {
391 wpa_printf(MSG_INFO
, "EAP-PAX: Unsupported DH Group ID 0x%x",
397 if (req
->public_key_id
!= EAP_PAX_PUBLIC_KEY_NONE
) {
398 wpa_printf(MSG_INFO
, "EAP-PAX: Unsupported Public Key ID 0x%x",
404 if (req
->flags
& EAP_PAX_FLAGS_MF
) {
405 /* TODO: add support for reassembling fragments */
406 wpa_printf(MSG_INFO
, "EAP-PAX: fragmentation not supported - "
412 icv
= pos
+ len
- EAP_PAX_ICV_LEN
;
413 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: ICV", icv
, EAP_PAX_ICV_LEN
);
414 if (req
->op_code
== EAP_PAX_OP_STD_1
) {
415 eap_pax_mac(req
->mac_id
, (u8
*) "", 0,
416 wpabuf_head(reqData
), mlen
, NULL
, 0, NULL
, 0,
419 eap_pax_mac(req
->mac_id
, data
->ick
, EAP_PAX_ICK_LEN
,
420 wpabuf_head(reqData
), mlen
, NULL
, 0, NULL
, 0,
423 if (os_memcmp(icv
, icvbuf
, EAP_PAX_ICV_LEN
) != 0) {
424 wpa_printf(MSG_DEBUG
, "EAP-PAX: invalid ICV - ignoring the "
426 wpa_hexdump(MSG_MSGDUMP
, "EAP-PAX: expected ICV",
427 icvbuf
, EAP_PAX_ICV_LEN
);
433 ret
->methodState
= METHOD_MAY_CONT
;
434 ret
->decision
= DECISION_FAIL
;
435 ret
->allowNotifications
= TRUE
;
437 switch (req
->op_code
) {
438 case EAP_PAX_OP_STD_1
:
439 resp
= eap_pax_process_std_1(data
, ret
, id
, req
, flen
);
441 case EAP_PAX_OP_STD_3
:
442 resp
= eap_pax_process_std_3(data
, ret
, id
, req
, flen
);
445 wpa_printf(MSG_DEBUG
, "EAP-PAX: ignoring message with unknown "
446 "op_code %d", req
->op_code
);
451 if (ret
->methodState
== METHOD_DONE
) {
452 ret
->allowNotifications
= FALSE
;
459 static Boolean
eap_pax_isKeyAvailable(struct eap_sm
*sm
, void *priv
)
461 struct eap_pax_data
*data
= priv
;
462 return data
->state
== PAX_DONE
;
466 static u8
* eap_pax_getKey(struct eap_sm
*sm
, void *priv
, size_t *len
)
468 struct eap_pax_data
*data
= priv
;
471 if (data
->state
!= PAX_DONE
)
474 key
= os_malloc(EAP_MSK_LEN
);
479 eap_pax_kdf(data
->mac_id
, data
->mk
, EAP_PAX_MK_LEN
,
480 "Master Session Key", data
->rand
.e
, 2 * EAP_PAX_RAND_LEN
,
487 static u8
* eap_pax_get_emsk(struct eap_sm
*sm
, void *priv
, size_t *len
)
489 struct eap_pax_data
*data
= priv
;
492 if (data
->state
!= PAX_DONE
)
495 key
= os_malloc(EAP_EMSK_LEN
);
500 eap_pax_kdf(data
->mac_id
, data
->mk
, EAP_PAX_MK_LEN
,
501 "Extended Master Session Key",
502 data
->rand
.e
, 2 * EAP_PAX_RAND_LEN
,
509 int eap_peer_pax_register(void)
511 struct eap_method
*eap
;
514 eap
= eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION
,
515 EAP_VENDOR_IETF
, EAP_TYPE_PAX
, "PAX");
519 eap
->init
= eap_pax_init
;
520 eap
->deinit
= eap_pax_deinit
;
521 eap
->process
= eap_pax_process
;
522 eap
->isKeyAvailable
= eap_pax_isKeyAvailable
;
523 eap
->getKey
= eap_pax_getKey
;
524 eap
->get_emsk
= eap_pax_get_emsk
;
526 ret
= eap_peer_method_register(eap
);
528 eap_peer_method_free(eap
);