udp: Merge udp_send and udp_output
[dragonfly.git] / contrib / wpa_supplicant / src / eap_server / eap_pax.c
1 /*
2  * hostapd / EAP-PAX (RFC 4746) server
3  * Copyright (c) 2005-2007, Jouni Malinen <j@w1.fi>
4  *
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.
8  *
9  * Alternatively, this software may be distributed under the terms of BSD
10  * license.
11  *
12  * See README and COPYING for more details.
13  */
14
15 #include "includes.h"
16
17 #include "common.h"
18 #include "eap_server/eap_i.h"
19 #include "eap_common/eap_pax_common.h"
20
21 /*
22  * Note: only PAX_STD subprotocol is currently supported
23  *
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),
27  * RSAES-OAEP).
28  */
29
30 struct eap_pax_data {
31         enum { PAX_STD_1, PAX_STD_3, SUCCESS, FAILURE } state;
32         u8 mac_id;
33         union {
34                 u8 e[2 * EAP_PAX_RAND_LEN];
35                 struct {
36                         u8 x[EAP_PAX_RAND_LEN]; /* server rand */
37                         u8 y[EAP_PAX_RAND_LEN]; /* client rand */
38                 } r;
39         } rand;
40         u8 ak[EAP_PAX_AK_LEN];
41         u8 mk[EAP_PAX_MK_LEN];
42         u8 ck[EAP_PAX_CK_LEN];
43         u8 ick[EAP_PAX_ICK_LEN];
44         int keys_set;
45         char *cid;
46         size_t cid_len;
47 };
48
49
50 static void * eap_pax_init(struct eap_sm *sm)
51 {
52         struct eap_pax_data *data;
53
54         data = os_zalloc(sizeof(*data));
55         if (data == NULL)
56                 return NULL;
57         data->state = PAX_STD_1;
58         /*
59          * TODO: make this configurable once EAP_PAX_HMAC_SHA256_128 is
60          * supported
61          */
62         data->mac_id = EAP_PAX_MAC_HMAC_SHA1_128;
63
64         return data;
65 }
66
67
68 static void eap_pax_reset(struct eap_sm *sm, void *priv)
69 {
70         struct eap_pax_data *data = priv;
71         os_free(data->cid);
72         os_free(data);
73 }
74
75
76 static struct wpabuf * eap_pax_build_std_1(struct eap_sm *sm,
77                                            struct eap_pax_data *data, u8 id)
78 {
79         struct wpabuf *req;
80         struct eap_pax_hdr *pax;
81         u8 *pos;
82
83         wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-1 (sending)");
84
85         if (os_get_random(data->rand.r.x, EAP_PAX_RAND_LEN)) {
86                 wpa_printf(MSG_ERROR, "EAP-PAX: Failed to get random data");
87                 data->state = FAILURE;
88                 return NULL;
89         }
90
91         req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PAX,
92                             sizeof(*pax) + 2 + EAP_PAX_RAND_LEN +
93                             EAP_PAX_ICV_LEN, EAP_CODE_REQUEST, id);
94         if (req == NULL) {
95                 wpa_printf(MSG_ERROR, "EAP-PAX: Failed to allocate memory "
96                            "request");
97                 data->state = FAILURE;
98                 return NULL;
99         }
100
101         pax = wpabuf_put(req, sizeof(*pax));
102         pax->op_code = EAP_PAX_OP_STD_1;
103         pax->flags = 0;
104         pax->mac_id = data->mac_id;
105         pax->dh_group_id = EAP_PAX_DH_GROUP_NONE;
106         pax->public_key_id = EAP_PAX_PUBLIC_KEY_NONE;
107
108         wpabuf_put_be16(req, EAP_PAX_RAND_LEN);
109         wpabuf_put_data(req, data->rand.r.x, EAP_PAX_RAND_LEN);
110         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: A = X (server rand)",
111                     data->rand.r.x, EAP_PAX_RAND_LEN);
112
113         pos = wpabuf_put(req, EAP_PAX_MAC_LEN);
114         eap_pax_mac(data->mac_id, (u8 *) "", 0,
115                     wpabuf_mhead(req), wpabuf_len(req) - EAP_PAX_ICV_LEN,
116                     NULL, 0, NULL, 0, pos);
117         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN);
118
119         return req;
120 }
121
122
123 static struct wpabuf * eap_pax_build_std_3(struct eap_sm *sm,
124                                            struct eap_pax_data *data, u8 id)
125 {
126         struct wpabuf *req;
127         struct eap_pax_hdr *pax;
128         u8 *pos;
129
130         wpa_printf(MSG_DEBUG, "EAP-PAX: PAX_STD-3 (sending)");
131
132         req = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PAX,
133                             sizeof(*pax) + 2 + EAP_PAX_MAC_LEN +
134                             EAP_PAX_ICV_LEN, EAP_CODE_REQUEST, id);
135         if (req == NULL) {
136                 wpa_printf(MSG_ERROR, "EAP-PAX: Failed to allocate memory "
137                            "request");
138                 data->state = FAILURE;
139                 return NULL;
140         }
141
142         pax = wpabuf_put(req, sizeof(*pax));
143         pax->op_code = EAP_PAX_OP_STD_3;
144         pax->flags = 0;
145         pax->mac_id = data->mac_id;
146         pax->dh_group_id = EAP_PAX_DH_GROUP_NONE;
147         pax->public_key_id = EAP_PAX_PUBLIC_KEY_NONE;
148
149         wpabuf_put_be16(req, EAP_PAX_MAC_LEN);
150         pos = wpabuf_put(req, EAP_PAX_MAC_LEN);
151         eap_pax_mac(data->mac_id, data->ck, EAP_PAX_CK_LEN,
152                     data->rand.r.y, EAP_PAX_RAND_LEN,
153                     (u8 *) data->cid, data->cid_len, NULL, 0, pos);
154         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: MAC_CK(B, CID)",
155                     pos, EAP_PAX_MAC_LEN);
156         pos += EAP_PAX_MAC_LEN;
157
158         /* Optional ADE could be added here, if needed */
159
160         pos = wpabuf_put(req, EAP_PAX_MAC_LEN);
161         eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN,
162                     wpabuf_mhead(req), wpabuf_len(req) - EAP_PAX_ICV_LEN,
163                     NULL, 0, NULL, 0, pos);
164         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN);
165
166         return req;
167 }
168
169
170 static struct wpabuf * eap_pax_buildReq(struct eap_sm *sm, void *priv, u8 id)
171 {
172         struct eap_pax_data *data = priv;
173
174         switch (data->state) {
175         case PAX_STD_1:
176                 return eap_pax_build_std_1(sm, data, id);
177         case PAX_STD_3:
178                 return eap_pax_build_std_3(sm, data, id);
179         default:
180                 wpa_printf(MSG_DEBUG, "EAP-PAX: Unknown state %d in buildReq",
181                            data->state);
182                 break;
183         }
184         return NULL;
185 }
186
187
188 static Boolean eap_pax_check(struct eap_sm *sm, void *priv,
189                              struct wpabuf *respData)
190 {
191         struct eap_pax_data *data = priv;
192         struct eap_pax_hdr *resp;
193         const u8 *pos;
194         size_t len, mlen;
195         u8 icvbuf[EAP_PAX_ICV_LEN], *icv;
196
197         pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PAX, respData, &len);
198         if (pos == NULL || len < sizeof(*resp)) {
199                 wpa_printf(MSG_INFO, "EAP-PAX: Invalid frame");
200                 return TRUE;
201         }
202
203         mlen = sizeof(struct eap_hdr) + 1 + len;
204         resp = (struct eap_pax_hdr *) pos;
205
206         wpa_printf(MSG_DEBUG, "EAP-PAX: received frame: op_code 0x%x "
207                    "flags 0x%x mac_id 0x%x dh_group_id 0x%x "
208                    "public_key_id 0x%x",
209                    resp->op_code, resp->flags, resp->mac_id, resp->dh_group_id,
210                    resp->public_key_id);
211         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: received payload",
212                     (u8 *) (resp + 1), len - sizeof(*resp) - EAP_PAX_ICV_LEN);
213
214         if (data->state == PAX_STD_1 &&
215             resp->op_code != EAP_PAX_OP_STD_2) {
216                 wpa_printf(MSG_DEBUG, "EAP-PAX: Expected PAX_STD-2 - "
217                            "ignore op %d", resp->op_code);
218                 return TRUE;
219         }
220
221         if (data->state == PAX_STD_3 &&
222             resp->op_code != EAP_PAX_OP_ACK) {
223                 wpa_printf(MSG_DEBUG, "EAP-PAX: Expected PAX-ACK - "
224                            "ignore op %d", resp->op_code);
225                 return TRUE;
226         }
227
228         if (resp->op_code != EAP_PAX_OP_STD_2 &&
229             resp->op_code != EAP_PAX_OP_ACK) {
230                 wpa_printf(MSG_DEBUG, "EAP-PAX: Unknown op_code 0x%x",
231                            resp->op_code);
232         }
233
234         if (data->mac_id != resp->mac_id) {
235                 wpa_printf(MSG_DEBUG, "EAP-PAX: Expected MAC ID 0x%x, "
236                            "received 0x%x", data->mac_id, resp->mac_id);
237                 return TRUE;
238         }
239
240         if (resp->dh_group_id != EAP_PAX_DH_GROUP_NONE) {
241                 wpa_printf(MSG_INFO, "EAP-PAX: Expected DH Group ID 0x%x, "
242                            "received 0x%x", EAP_PAX_DH_GROUP_NONE,
243                            resp->dh_group_id);
244                 return TRUE;
245         }
246
247         if (resp->public_key_id != EAP_PAX_PUBLIC_KEY_NONE) {
248                 wpa_printf(MSG_INFO, "EAP-PAX: Expected Public Key ID 0x%x, "
249                            "received 0x%x", EAP_PAX_PUBLIC_KEY_NONE,
250                            resp->public_key_id);
251                 return TRUE;
252         }
253
254         if (resp->flags & EAP_PAX_FLAGS_MF) {
255                 /* TODO: add support for reassembling fragments */
256                 wpa_printf(MSG_INFO, "EAP-PAX: fragmentation not supported");
257                 return TRUE;
258         }
259
260         if (resp->flags & EAP_PAX_FLAGS_CE) {
261                 wpa_printf(MSG_INFO, "EAP-PAX: Unexpected CE flag");
262                 return TRUE;
263         }
264
265         if (data->keys_set) {
266                 if (len - sizeof(*resp) < EAP_PAX_ICV_LEN) {
267                         wpa_printf(MSG_INFO, "EAP-PAX: No ICV in the packet");
268                         return TRUE;
269                 }
270                 icv = wpabuf_mhead_u8(respData) + mlen - EAP_PAX_ICV_LEN;
271                 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", icv, EAP_PAX_ICV_LEN);
272                 eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN,
273                             wpabuf_mhead(respData),
274                             wpabuf_len(respData) - EAP_PAX_ICV_LEN,
275                             NULL, 0, NULL, 0, icvbuf);
276                 if (os_memcmp(icvbuf, icv, EAP_PAX_ICV_LEN) != 0) {
277                         wpa_printf(MSG_INFO, "EAP-PAX: Invalid ICV");
278                         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected ICV",
279                                     icvbuf, EAP_PAX_ICV_LEN);
280                         return TRUE;
281                 }
282         }
283
284         return FALSE;
285 }
286
287
288 static void eap_pax_process_std_2(struct eap_sm *sm,
289                                   struct eap_pax_data *data,
290                                   struct wpabuf *respData)
291 {
292         struct eap_pax_hdr *resp;
293         u8 mac[EAP_PAX_MAC_LEN], icvbuf[EAP_PAX_ICV_LEN];
294         const u8 *pos;
295         size_t len, left;
296         int i;
297
298         if (data->state != PAX_STD_1)
299                 return;
300
301         wpa_printf(MSG_DEBUG, "EAP-PAX: Received PAX_STD-2");
302
303         pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PAX, respData, &len);
304         if (pos == NULL || len < sizeof(*resp) + EAP_PAX_ICV_LEN)
305                 return;
306
307         resp = (struct eap_pax_hdr *) pos;
308         pos = (u8 *) (resp + 1);
309         left = len - sizeof(*resp);
310
311         if (left < 2 + EAP_PAX_RAND_LEN ||
312             WPA_GET_BE16(pos) != EAP_PAX_RAND_LEN) {
313                 wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (B)");
314                 return;
315         }
316         pos += 2;
317         left -= 2;
318         os_memcpy(data->rand.r.y, pos, EAP_PAX_RAND_LEN);
319         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Y (client rand)",
320                     data->rand.r.y, EAP_PAX_RAND_LEN);
321         pos += EAP_PAX_RAND_LEN;
322         left -= EAP_PAX_RAND_LEN;
323
324         if (left < 2 || (size_t) 2 + WPA_GET_BE16(pos) > left) {
325                 wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (CID)");
326                 return;
327         }
328         data->cid_len = WPA_GET_BE16(pos);
329         os_free(data->cid);
330         data->cid = os_malloc(data->cid_len);
331         if (data->cid == NULL) {
332                 wpa_printf(MSG_INFO, "EAP-PAX: Failed to allocate memory for "
333                            "CID");
334                 return;
335         }
336         os_memcpy(data->cid, pos + 2, data->cid_len);
337         pos += 2 + data->cid_len;
338         left -= 2 + data->cid_len;
339         wpa_hexdump_ascii(MSG_MSGDUMP, "EAP-PAX: CID",
340                           (u8 *) data->cid, data->cid_len);
341
342         if (left < 2 + EAP_PAX_MAC_LEN ||
343             WPA_GET_BE16(pos) != EAP_PAX_MAC_LEN) {
344                 wpa_printf(MSG_INFO, "EAP-PAX: Too short PAX_STD-2 (MAC_CK)");
345                 return;
346         }
347         pos += 2;
348         left -= 2;
349         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: MAC_CK(A, B, CID)",
350                     pos, EAP_PAX_MAC_LEN);
351
352         if (eap_user_get(sm, (u8 *) data->cid, data->cid_len, 0) < 0) {
353                 wpa_hexdump_ascii(MSG_DEBUG, "EAP-PAX: unknown CID",
354                                   (u8 *) data->cid, data->cid_len);
355                 data->state = FAILURE;
356                 return;
357         }
358
359         for (i = 0;
360              i < EAP_MAX_METHODS &&
361                      (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
362                       sm->user->methods[i].method != EAP_TYPE_NONE);
363              i++) {
364                 if (sm->user->methods[i].vendor == EAP_VENDOR_IETF &&
365                     sm->user->methods[i].method == EAP_TYPE_PAX)
366                         break;
367         }
368
369         if (i >= EAP_MAX_METHODS ||
370             sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
371             sm->user->methods[i].method != EAP_TYPE_PAX) {
372                 wpa_hexdump_ascii(MSG_DEBUG,
373                                   "EAP-PAX: EAP-PAX not enabled for CID",
374                                   (u8 *) data->cid, data->cid_len);
375                 data->state = FAILURE;
376                 return;
377         }
378
379         if (sm->user->password == NULL ||
380             sm->user->password_len != EAP_PAX_AK_LEN) {
381                 wpa_hexdump_ascii(MSG_DEBUG, "EAP-PAX: invalid password in "
382                                   "user database for CID",
383                                   (u8 *) data->cid, data->cid_len);
384                 data->state = FAILURE;
385                 return;
386         }
387         os_memcpy(data->ak, sm->user->password, EAP_PAX_AK_LEN);
388
389         if (eap_pax_initial_key_derivation(data->mac_id, data->ak,
390                                            data->rand.e, data->mk, data->ck,
391                                            data->ick) < 0) {
392                 wpa_printf(MSG_INFO, "EAP-PAX: Failed to complete initial "
393                            "key derivation");
394                 data->state = FAILURE;
395                 return;
396         }
397         data->keys_set = 1;
398
399         eap_pax_mac(data->mac_id, data->ck, EAP_PAX_CK_LEN,
400                     data->rand.r.x, EAP_PAX_RAND_LEN,
401                     data->rand.r.y, EAP_PAX_RAND_LEN,
402                     (u8 *) data->cid, data->cid_len, mac);
403         if (os_memcmp(mac, pos, EAP_PAX_MAC_LEN) != 0) {
404                 wpa_printf(MSG_INFO, "EAP-PAX: Invalid MAC_CK(A, B, CID) in "
405                            "PAX_STD-2");
406                 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected MAC_CK(A, B, CID)",
407                             mac, EAP_PAX_MAC_LEN);
408                 data->state = FAILURE;
409                 return;
410         }
411
412         pos += EAP_PAX_MAC_LEN;
413         left -= EAP_PAX_MAC_LEN;
414
415         if (left < EAP_PAX_ICV_LEN) {
416                 wpa_printf(MSG_INFO, "EAP-PAX: Too short ICV (%lu) in "
417                            "PAX_STD-2", (unsigned long) left);
418                 return;
419         }
420         wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ICV", pos, EAP_PAX_ICV_LEN);
421         eap_pax_mac(data->mac_id, data->ick, EAP_PAX_ICK_LEN,
422                     wpabuf_head(respData),
423                     wpabuf_len(respData) - EAP_PAX_ICV_LEN, NULL, 0, NULL, 0,
424                     icvbuf);
425         if (os_memcmp(icvbuf, pos, EAP_PAX_ICV_LEN) != 0) {
426                 wpa_printf(MSG_INFO, "EAP-PAX: Invalid ICV in PAX_STD-2");
427                 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: Expected ICV",
428                             icvbuf, EAP_PAX_ICV_LEN);
429                 return;
430         }
431         pos += EAP_PAX_ICV_LEN;
432         left -= EAP_PAX_ICV_LEN;
433
434         if (left > 0) {
435                 wpa_hexdump(MSG_MSGDUMP, "EAP-PAX: ignored extra payload",
436                             pos, left);
437         }
438
439         data->state = PAX_STD_3;
440 }
441
442
443 static void eap_pax_process_ack(struct eap_sm *sm,
444                                 struct eap_pax_data *data,
445                                 struct wpabuf *respData)
446 {
447         if (data->state != PAX_STD_3)
448                 return;
449
450         wpa_printf(MSG_DEBUG, "EAP-PAX: Received PAX-ACK - authentication "
451                    "completed successfully");
452         data->state = SUCCESS;
453 }
454
455
456 static void eap_pax_process(struct eap_sm *sm, void *priv,
457                             struct wpabuf *respData)
458 {
459         struct eap_pax_data *data = priv;
460         struct eap_pax_hdr *resp;
461         const u8 *pos;
462         size_t len;
463
464         if (sm->user == NULL || sm->user->password == NULL) {
465                 wpa_printf(MSG_INFO, "EAP-PAX: Plaintext password not "
466                            "configured");
467                 data->state = FAILURE;
468                 return;
469         }
470
471         pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PAX, respData, &len);
472         if (pos == NULL || len < sizeof(*resp))
473                 return;
474
475         resp = (struct eap_pax_hdr *) pos;
476
477         switch (resp->op_code) {
478         case EAP_PAX_OP_STD_2:
479                 eap_pax_process_std_2(sm, data, respData);
480                 break;
481         case EAP_PAX_OP_ACK:
482                 eap_pax_process_ack(sm, data, respData);
483                 break;
484         }
485 }
486
487
488 static Boolean eap_pax_isDone(struct eap_sm *sm, void *priv)
489 {
490         struct eap_pax_data *data = priv;
491         return data->state == SUCCESS || data->state == FAILURE;
492 }
493
494
495 static u8 * eap_pax_getKey(struct eap_sm *sm, void *priv, size_t *len)
496 {
497         struct eap_pax_data *data = priv;
498         u8 *key;
499
500         if (data->state != SUCCESS)
501                 return NULL;
502
503         key = os_malloc(EAP_MSK_LEN);
504         if (key == NULL)
505                 return NULL;
506
507         *len = EAP_MSK_LEN;
508         eap_pax_kdf(data->mac_id, data->mk, EAP_PAX_MK_LEN,
509                     "Master Session Key", data->rand.e, 2 * EAP_PAX_RAND_LEN,
510                     EAP_MSK_LEN, key);
511
512         return key;
513 }
514
515
516 static u8 * eap_pax_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
517 {
518         struct eap_pax_data *data = priv;
519         u8 *key;
520
521         if (data->state != SUCCESS)
522                 return NULL;
523
524         key = os_malloc(EAP_EMSK_LEN);
525         if (key == NULL)
526                 return NULL;
527
528         *len = EAP_EMSK_LEN;
529         eap_pax_kdf(data->mac_id, data->mk, EAP_PAX_MK_LEN,
530                     "Extended Master Session Key",
531                     data->rand.e, 2 * EAP_PAX_RAND_LEN,
532                     EAP_EMSK_LEN, key);
533
534         return key;
535 }
536
537
538 static Boolean eap_pax_isSuccess(struct eap_sm *sm, void *priv)
539 {
540         struct eap_pax_data *data = priv;
541         return data->state == SUCCESS;
542 }
543
544
545 int eap_server_pax_register(void)
546 {
547         struct eap_method *eap;
548         int ret;
549
550         eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
551                                       EAP_VENDOR_IETF, EAP_TYPE_PAX, "PAX");
552         if (eap == NULL)
553                 return -1;
554
555         eap->init = eap_pax_init;
556         eap->reset = eap_pax_reset;
557         eap->buildReq = eap_pax_buildReq;
558         eap->check = eap_pax_check;
559         eap->process = eap_pax_process;
560         eap->isDone = eap_pax_isDone;
561         eap->getKey = eap_pax_getKey;
562         eap->isSuccess = eap_pax_isSuccess;
563         eap->get_emsk = eap_pax_get_emsk;
564
565         ret = eap_server_method_register(eap);
566         if (ret)
567                 eap_server_method_free(eap);
568         return ret;
569 }