1 /*
2 * EAP peer method: EAP-AKA (RFC 4187) and EAP-AKA' (RFC 5448)
3 * Copyright (c) 2004-2012, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "pcsc_funcs.h"
13 #include "crypto/crypto.h"
14 #include "crypto/sha1.h"
15 #include "crypto/sha256.h"
16 #include "crypto/milenage.h"
17 #include "eap_common/eap_sim_common.h"
18 #include "eap_config.h"
19 #include "eap_i.h"
20
21
22 struct eap_aka_data {
23 u8 ik[EAP_AKA_IK_LEN], ck[EAP_AKA_CK_LEN], res[EAP_AKA_RES_MAX_LEN];
24 size_t res_len;
25 u8 nonce_s[EAP_SIM_NONCE_S_LEN];
26 u8 mk[EAP_SIM_MK_LEN];
27 u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
28 u8 k_encr[EAP_SIM_K_ENCR_LEN];
29 u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
30 u8 msk[EAP_SIM_KEYING_DATA_LEN];
31 u8 emsk[EAP_EMSK_LEN];
32 u8 rand[EAP_AKA_RAND_LEN], autn[EAP_AKA_AUTN_LEN];
33 u8 auts[EAP_AKA_AUTS_LEN];
34
35 int num_id_req, num_notification;
36 u8 *pseudonym;
37 size_t pseudonym_len;
38 u8 *reauth_id;
39 size_t reauth_id_len;
40 int reauth;
41 unsigned int counter, counter_too_small;
42 u8 *last_eap_identity;
43 size_t last_eap_identity_len;
44 enum {
45 CONTINUE, RESULT_SUCCESS, SUCCESS, FAILURE
46 } state;
47
48 struct wpabuf *id_msgs;
49 int prev_id;
50 int result_ind, use_result_ind;
51 u8 eap_method;
52 u8 *network_name;
53 size_t network_name_len;
54 u16 kdf;
55 int kdf_negotiation;
56 };
57
58
59 #ifndef CONFIG_NO_STDOUT_DEBUG
eap_aka_state_txt(int state)60 static const char * eap_aka_state_txt(int state)
61 {
62 switch (state) {
63 case CONTINUE:
64 return "CONTINUE";
65 case RESULT_SUCCESS:
66 return "RESULT_SUCCESS";
67 case SUCCESS:
68 return "SUCCESS";
69 case FAILURE:
70 return "FAILURE";
71 default:
72 return "?";
73 }
74 }
75 #endif /* CONFIG_NO_STDOUT_DEBUG */
76
77
eap_aka_state(struct eap_aka_data * data,int state)78 static void eap_aka_state(struct eap_aka_data *data, int state)
79 {
80 wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
81 eap_aka_state_txt(data->state),
82 eap_aka_state_txt(state));
83 data->state = state;
84 }
85
86
eap_aka_init(struct eap_sm * sm)87 static void * eap_aka_init(struct eap_sm *sm)
88 {
89 struct eap_aka_data *data;
90 const char *phase1 = eap_get_config_phase1(sm);
91 struct eap_peer_config *config = eap_get_config(sm);
92
93 data = os_zalloc(sizeof(*data));
94 if (data == NULL)
95 return NULL;
96
97 data->eap_method = EAP_TYPE_AKA;
98
99 eap_aka_state(data, CONTINUE);
100 data->prev_id = -1;
101
102 data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
103
104 if (config && config->anonymous_identity) {
105 data->pseudonym = os_malloc(config->anonymous_identity_len);
106 if (data->pseudonym) {
107 os_memcpy(data->pseudonym, config->anonymous_identity,
108 config->anonymous_identity_len);
109 data->pseudonym_len = config->anonymous_identity_len;
110 }
111 }
112
113 return data;
114 }
115
116
117 #ifdef EAP_AKA_PRIME
eap_aka_prime_init(struct eap_sm * sm)118 static void * eap_aka_prime_init(struct eap_sm *sm)
119 {
120 struct eap_aka_data *data = eap_aka_init(sm);
121 if (data == NULL)
122 return NULL;
123 data->eap_method = EAP_TYPE_AKA_PRIME;
124 return data;
125 }
126 #endif /* EAP_AKA_PRIME */
127
128
eap_aka_clear_keys(struct eap_aka_data * data,int reauth)129 static void eap_aka_clear_keys(struct eap_aka_data *data, int reauth)
130 {
131 if (!reauth) {
132 os_memset(data->mk, 0, EAP_SIM_MK_LEN);
133 os_memset(data->k_aut, 0, EAP_AKA_PRIME_K_AUT_LEN);
134 os_memset(data->k_encr, 0, EAP_SIM_K_ENCR_LEN);
135 os_memset(data->k_re, 0, EAP_AKA_PRIME_K_RE_LEN);
136 }
137 os_memset(data->msk, 0, EAP_SIM_KEYING_DATA_LEN);
138 os_memset(data->emsk, 0, EAP_EMSK_LEN);
139 os_memset(data->autn, 0, EAP_AKA_AUTN_LEN);
140 os_memset(data->auts, 0, EAP_AKA_AUTS_LEN);
141 }
142
143
eap_aka_deinit(struct eap_sm * sm,void * priv)144 static void eap_aka_deinit(struct eap_sm *sm, void *priv)
145 {
146 struct eap_aka_data *data = priv;
147 if (data) {
148 os_free(data->pseudonym);
149 os_free(data->reauth_id);
150 os_free(data->last_eap_identity);
151 wpabuf_free(data->id_msgs);
152 os_free(data->network_name);
153 eap_aka_clear_keys(data, 0);
154 os_free(data);
155 }
156 }
157
158
eap_aka_ext_sim_req(struct eap_sm * sm,struct eap_aka_data * data)159 static int eap_aka_ext_sim_req(struct eap_sm *sm, struct eap_aka_data *data)
160 {
161 char req[200], *pos, *end;
162
163 wpa_printf(MSG_DEBUG, "EAP-AKA: Use external USIM processing");
164 pos = req;
165 end = pos + sizeof(req);
166 pos += os_snprintf(pos, end - pos, "UMTS-AUTH");
167 pos += os_snprintf(pos, end - pos, ":");
168 pos += wpa_snprintf_hex(pos, end - pos, data->rand, EAP_AKA_RAND_LEN);
169 pos += os_snprintf(pos, end - pos, ":");
170 wpa_snprintf_hex(pos, end - pos, data->autn, EAP_AKA_AUTN_LEN);
171
172 eap_sm_request_sim(sm, req);
173 return 1;
174 }
175
176
eap_aka_ext_sim_result(struct eap_sm * sm,struct eap_aka_data * data,struct eap_peer_config * conf)177 static int eap_aka_ext_sim_result(struct eap_sm *sm, struct eap_aka_data *data,
178 struct eap_peer_config *conf)
179 {
180 char *resp, *pos;
181
182 wpa_printf(MSG_DEBUG,
183 "EAP-AKA: Use result from external USIM processing");
184
185 resp = conf->external_sim_resp;
186 conf->external_sim_resp = NULL;
187
188 if (os_strncmp(resp, "UMTS-AUTS:", 10) == 0) {
189 pos = resp + 10;
190 if (hexstr2bin(pos, data->auts, EAP_AKA_AUTS_LEN) < 0)
191 goto invalid;
192 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: AUTS", data->auts,
193 EAP_AKA_AUTS_LEN);
194 os_free(resp);
195 return -2;
196 }
197
198 if (os_strncmp(resp, "UMTS-AUTH:", 10) != 0) {
199 wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized external USIM processing response");
200 os_free(resp);
201 return -1;
202 }
203
204 pos = resp + 10;
205 wpa_hexdump(MSG_DEBUG, "EAP-AKA: RAND", data->rand, EAP_AKA_RAND_LEN);
206
207 if (hexstr2bin(pos, data->ik, EAP_AKA_IK_LEN) < 0)
208 goto invalid;
209 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, EAP_AKA_IK_LEN);
210 pos += EAP_AKA_IK_LEN * 2;
211 if (*pos != ':')
212 goto invalid;
213 pos++;
214
215 if (hexstr2bin(pos, data->ck, EAP_AKA_CK_LEN) < 0)
216 goto invalid;
217 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, EAP_AKA_CK_LEN);
218 pos += EAP_AKA_CK_LEN * 2;
219 if (*pos != ':')
220 goto invalid;
221 pos++;
222
223 data->res_len = os_strlen(pos) / 2;
224 if (data->res_len > EAP_AKA_RES_MAX_LEN) {
225 data->res_len = 0;
226 goto invalid;
227 }
228 if (hexstr2bin(pos, data->res, data->res_len) < 0)
229 goto invalid;
230 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: RES", data->res, data->res_len);
231
232 os_free(resp);
233 return 0;
234
235 invalid:
236 wpa_printf(MSG_DEBUG, "EAP-AKA: Invalid external USIM processing UMTS-AUTH response");
237 os_free(resp);
238 return -1;
239 }
240
241
eap_aka_umts_auth(struct eap_sm * sm,struct eap_aka_data * data)242 static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
243 {
244 struct eap_peer_config *conf;
245
246 wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
247
248 conf = eap_get_config(sm);
249 if (conf == NULL)
250 return -1;
251
252 if (sm->external_sim) {
253 if (conf->external_sim_resp)
254 return eap_aka_ext_sim_result(sm, data, conf);
255 else
256 return eap_aka_ext_sim_req(sm, data);
257 }
258
259 if (conf->pcsc) {
260 return scard_umts_auth(sm->scard_ctx, data->rand,
261 data->autn, data->res, &data->res_len,
262 data->ik, data->ck, data->auts);
263 }
264
265 #ifdef CONFIG_USIM_SIMULATOR
266 if (conf->password) {
267 u8 opc[16], k[16], sqn[6];
268 const char *pos;
269 wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
270 "implementation for UMTS authentication");
271 if (conf->password_len < 78) {
272 wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
273 "password");
274 return -1;
275 }
276 pos = (const char *) conf->password;
277 if (hexstr2bin(pos, k, 16))
278 return -1;
279 pos += 32;
280 if (*pos != ':')
281 return -1;
282 pos++;
283
284 if (hexstr2bin(pos, opc, 16))
285 return -1;
286 pos += 32;
287 if (*pos != ':')
288 return -1;
289 pos++;
290
291 if (hexstr2bin(pos, sqn, 6))
292 return -1;
293
294 return milenage_check(opc, k, sqn, data->rand, data->autn,
295 data->ik, data->ck,
296 data->res, &data->res_len, data->auts);
297 }
298 #endif /* CONFIG_USIM_SIMULATOR */
299
300 #ifdef CONFIG_USIM_HARDCODED
301 wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
302 "testing");
303
304 /* These hardcoded Kc and SRES values are used for testing.
305 * Could consider making them configurable. */
306 os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
307 data->res_len = EAP_AKA_RES_MAX_LEN;
308 os_memset(data->ik, '3', EAP_AKA_IK_LEN);
309 os_memset(data->ck, '4', EAP_AKA_CK_LEN);
310 {
311 u8 autn[EAP_AKA_AUTN_LEN];
312 os_memset(autn, '1', EAP_AKA_AUTN_LEN);
313 if (os_memcmp_const(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
314 wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
315 "with expected value");
316 return -1;
317 }
318 }
319 #if 0
320 {
321 static int test_resync = 1;
322 if (test_resync) {
323 /* Test Resynchronization */
324 test_resync = 0;
325 return -2;
326 }
327 }
328 #endif
329 return 0;
330
331 #else /* CONFIG_USIM_HARDCODED */
332
333 wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorithm "
334 "enabled");
335 return -1;
336
337 #endif /* CONFIG_USIM_HARDCODED */
338 }
339
340
341 #define CLEAR_PSEUDONYM 0x01
342 #define CLEAR_REAUTH_ID 0x02
343 #define CLEAR_EAP_ID 0x04
344
eap_aka_clear_identities(struct eap_sm * sm,struct eap_aka_data * data,int id)345 static void eap_aka_clear_identities(struct eap_sm *sm,
346 struct eap_aka_data *data, int id)
347 {
348 if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
349 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
350 os_free(data->pseudonym);
351 data->pseudonym = NULL;
352 data->pseudonym_len = 0;
353 eap_set_anon_id(sm, NULL, 0);
354 }
355 if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
356 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
357 os_free(data->reauth_id);
358 data->reauth_id = NULL;
359 data->reauth_id_len = 0;
360 }
361 if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
362 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
363 os_free(data->last_eap_identity);
364 data->last_eap_identity = NULL;
365 data->last_eap_identity_len = 0;
366 }
367 }
368
369
eap_aka_learn_ids(struct eap_sm * sm,struct eap_aka_data * data,struct eap_sim_attrs * attr)370 static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
371 struct eap_sim_attrs *attr)
372 {
373 if (attr->next_pseudonym) {
374 const u8 *identity = NULL;
375 size_t identity_len = 0;
376 const u8 *realm = NULL;
377 size_t realm_len = 0;
378
379 wpa_hexdump_ascii(MSG_DEBUG,
380 "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
381 attr->next_pseudonym,
382 attr->next_pseudonym_len);
383 os_free(data->pseudonym);
384 /* Look for the realm of the permanent identity */
385 identity = eap_get_config_identity(sm, &identity_len);
386 if (identity) {
387 for (realm = identity, realm_len = identity_len;
388 realm_len > 0; realm_len--, realm++) {
389 if (*realm == '@')
390 break;
391 }
392 }
393 data->pseudonym = os_malloc(attr->next_pseudonym_len +
394 realm_len);
395 if (data->pseudonym == NULL) {
396 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
397 "next pseudonym");
398 data->pseudonym_len = 0;
399 return -1;
400 }
401 os_memcpy(data->pseudonym, attr->next_pseudonym,
402 attr->next_pseudonym_len);
403 if (realm_len) {
404 os_memcpy(data->pseudonym + attr->next_pseudonym_len,
405 realm, realm_len);
406 }
407 data->pseudonym_len = attr->next_pseudonym_len + realm_len;
408 eap_set_anon_id(sm, data->pseudonym, data->pseudonym_len);
409 }
410
411 if (attr->next_reauth_id) {
412 os_free(data->reauth_id);
413 data->reauth_id = os_malloc(attr->next_reauth_id_len);
414 if (data->reauth_id == NULL) {
415 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
416 "next reauth_id");
417 data->reauth_id_len = 0;
418 return -1;
419 }
420 os_memcpy(data->reauth_id, attr->next_reauth_id,
421 attr->next_reauth_id_len);
422 data->reauth_id_len = attr->next_reauth_id_len;
423 wpa_hexdump_ascii(MSG_DEBUG,
424 "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
425 data->reauth_id,
426 data->reauth_id_len);
427 }
428
429 return 0;
430 }
431
432
eap_aka_add_id_msg(struct eap_aka_data * data,const struct wpabuf * msg)433 static int eap_aka_add_id_msg(struct eap_aka_data *data,
434 const struct wpabuf *msg)
435 {
436 if (msg == NULL)
437 return -1;
438
439 if (data->id_msgs == NULL) {
440 data->id_msgs = wpabuf_dup(msg);
441 return data->id_msgs == NULL ? -1 : 0;
442 }
443
444 if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
445 return -1;
446 wpabuf_put_buf(data->id_msgs, msg);
447
448 return 0;
449 }
450
451
eap_aka_add_checkcode(struct eap_aka_data * data,struct eap_sim_msg * msg)452 static void eap_aka_add_checkcode(struct eap_aka_data *data,
453 struct eap_sim_msg *msg)
454 {
455 const u8 *addr;
456 size_t len;
457 u8 hash[SHA256_MAC_LEN];
458
459 wpa_printf(MSG_DEBUG, " AT_CHECKCODE");
460
461 if (data->id_msgs == NULL) {
462 /*
463 * No EAP-AKA/Identity packets were exchanged - send empty
464 * checkcode.
465 */
466 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
467 return;
468 }
469
470 /* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
471 addr = wpabuf_head(data->id_msgs);
472 len = wpabuf_len(data->id_msgs);
473 wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
474 #ifdef EAP_AKA_PRIME
475 if (data->eap_method == EAP_TYPE_AKA_PRIME)
476 sha256_vector(1, &addr, &len, hash);
477 else
478 #endif /* EAP_AKA_PRIME */
479 sha1_vector(1, &addr, &len, hash);
480
481 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
482 data->eap_method == EAP_TYPE_AKA_PRIME ?
483 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
484 }
485
486
eap_aka_verify_checkcode(struct eap_aka_data * data,const u8 * checkcode,size_t checkcode_len)487 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
488 const u8 *checkcode, size_t checkcode_len)
489 {
490 const u8 *addr;
491 size_t len;
492 u8 hash[SHA256_MAC_LEN];
493 size_t hash_len;
494
495 if (checkcode == NULL)
496 return -1;
497
498 if (data->id_msgs == NULL) {
499 if (checkcode_len != 0) {
500 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
501 "indicates that AKA/Identity messages were "
502 "used, but they were not");
503 return -1;
504 }
505 return 0;
506 }
507
508 hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
509 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
510
511 if (checkcode_len != hash_len) {
512 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
513 "indicates that AKA/Identity message were not "
514 "used, but they were");
515 return -1;
516 }
517
518 /* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
519 addr = wpabuf_head(data->id_msgs);
520 len = wpabuf_len(data->id_msgs);
521 #ifdef EAP_AKA_PRIME
522 if (data->eap_method == EAP_TYPE_AKA_PRIME)
523 sha256_vector(1, &addr, &len, hash);
524 else
525 #endif /* EAP_AKA_PRIME */
526 sha1_vector(1, &addr, &len, hash);
527
528 if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
529 wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
530 return -1;
531 }
532
533 return 0;
534 }
535
536
eap_aka_client_error(struct eap_aka_data * data,u8 id,int err)537 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
538 int err)
539 {
540 struct eap_sim_msg *msg;
541
542 eap_aka_state(data, FAILURE);
543 data->num_id_req = 0;
544 data->num_notification = 0;
545
546 wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
547 err);
548 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
549 EAP_AKA_SUBTYPE_CLIENT_ERROR);
550 eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
551 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
552 }
553
554
eap_aka_authentication_reject(struct eap_aka_data * data,u8 id)555 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
556 u8 id)
557 {
558 struct eap_sim_msg *msg;
559
560 eap_aka_state(data, FAILURE);
561 data->num_id_req = 0;
562 data->num_notification = 0;
563
564 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
565 "(id=%d)", id);
566 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
567 EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
568 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
569 }
570
571
eap_aka_synchronization_failure(struct eap_aka_data * data,u8 id)572 static struct wpabuf * eap_aka_synchronization_failure(
573 struct eap_aka_data *data, u8 id)
574 {
575 struct eap_sim_msg *msg;
576
577 data->num_id_req = 0;
578 data->num_notification = 0;
579
580 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
581 "(id=%d)", id);
582 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
583 EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
584 wpa_printf(MSG_DEBUG, " AT_AUTS");
585 eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
586 EAP_AKA_AUTS_LEN);
587 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
588 }
589
590
eap_aka_response_identity(struct eap_sm * sm,struct eap_aka_data * data,u8 id,enum eap_sim_id_req id_req)591 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
592 struct eap_aka_data *data,
593 u8 id,
594 enum eap_sim_id_req id_req)
595 {
596 const u8 *identity = NULL;
597 size_t identity_len = 0;
598 struct eap_sim_msg *msg;
599
600 data->reauth = 0;
601 if (id_req == ANY_ID && data->reauth_id) {
602 identity = data->reauth_id;
603 identity_len = data->reauth_id_len;
604 data->reauth = 1;
605 } else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
606 data->pseudonym) {
607 identity = data->pseudonym;
608 identity_len = data->pseudonym_len;
609 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
610 } else if (id_req != NO_ID_REQ) {
611 identity = eap_get_config_identity(sm, &identity_len);
612 if (identity) {
613 eap_aka_clear_identities(sm, data, CLEAR_PSEUDONYM |
614 CLEAR_REAUTH_ID);
615 }
616 }
617 if (id_req != NO_ID_REQ)
618 eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
619
620 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
621 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
622 EAP_AKA_SUBTYPE_IDENTITY);
623
624 if (identity) {
625 wpa_hexdump_ascii(MSG_DEBUG, " AT_IDENTITY",
626 identity, identity_len);
627 eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
628 identity, identity_len);
629 }
630
631 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
632 }
633
634
eap_aka_response_challenge(struct eap_aka_data * data,u8 id)635 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
636 u8 id)
637 {
638 struct eap_sim_msg *msg;
639
640 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
641 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
642 EAP_AKA_SUBTYPE_CHALLENGE);
643 wpa_printf(MSG_DEBUG, " AT_RES");
644 eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
645 data->res, data->res_len);
646 eap_aka_add_checkcode(data, msg);
647 if (data->use_result_ind) {
648 wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
649 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
650 }
651 wpa_printf(MSG_DEBUG, " AT_MAC");
652 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
653 return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, (u8 *) "",
654 0);
655 }
656
657
eap_aka_response_reauth(struct eap_aka_data * data,u8 id,int counter_too_small,const u8 * nonce_s)658 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
659 u8 id, int counter_too_small,
660 const u8 *nonce_s)
661 {
662 struct eap_sim_msg *msg;
663 unsigned int counter;
664
665 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
666 id);
667 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
668 EAP_AKA_SUBTYPE_REAUTHENTICATION);
669 wpa_printf(MSG_DEBUG, " AT_IV");
670 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
671 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
672
673 if (counter_too_small) {
674 wpa_printf(MSG_DEBUG, " *AT_COUNTER_TOO_SMALL");
675 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
676 counter = data->counter_too_small;
677 } else
678 counter = data->counter;
679
680 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", counter);
681 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
682
683 if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
684 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
685 "AT_ENCR_DATA");
686 eap_sim_msg_free(msg);
687 return NULL;
688 }
689 eap_aka_add_checkcode(data, msg);
690 if (data->use_result_ind) {
691 wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
692 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
693 }
694 wpa_printf(MSG_DEBUG, " AT_MAC");
695 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
696 return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, nonce_s,
697 EAP_SIM_NONCE_S_LEN);
698 }
699
700
eap_aka_response_notification(struct eap_aka_data * data,u8 id,u16 notification)701 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
702 u8 id, u16 notification)
703 {
704 struct eap_sim_msg *msg;
705 u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
706
707 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
708 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
709 EAP_AKA_SUBTYPE_NOTIFICATION);
710 if (k_aut && data->reauth) {
711 wpa_printf(MSG_DEBUG, " AT_IV");
712 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
713 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
714 EAP_SIM_AT_ENCR_DATA);
715 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", data->counter);
716 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
717 NULL, 0);
718 if (eap_sim_msg_add_encr_end(msg, data->k_encr,
719 EAP_SIM_AT_PADDING)) {
720 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
721 "AT_ENCR_DATA");
722 eap_sim_msg_free(msg);
723 return NULL;
724 }
725 }
726 if (k_aut) {
727 wpa_printf(MSG_DEBUG, " AT_MAC");
728 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
729 }
730 return eap_sim_msg_finish(msg, data->eap_method, k_aut, (u8 *) "", 0);
731 }
732
733
eap_aka_process_identity(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)734 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
735 struct eap_aka_data *data,
736 u8 id,
737 const struct wpabuf *reqData,
738 struct eap_sim_attrs *attr)
739 {
740 int id_error;
741 struct wpabuf *buf;
742
743 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
744
745 id_error = 0;
746 switch (attr->id_req) {
747 case NO_ID_REQ:
748 break;
749 case ANY_ID:
750 if (data->num_id_req > 0)
751 id_error++;
752 data->num_id_req++;
753 break;
754 case FULLAUTH_ID:
755 if (data->num_id_req > 1)
756 id_error++;
757 data->num_id_req++;
758 break;
759 case PERMANENT_ID:
760 if (data->num_id_req > 2)
761 id_error++;
762 data->num_id_req++;
763 break;
764 }
765 if (id_error) {
766 wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
767 "used within one authentication");
768 return eap_aka_client_error(data, id,
769 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
770 }
771
772 buf = eap_aka_response_identity(sm, data, id, attr->id_req);
773
774 if (data->prev_id != id) {
775 eap_aka_add_id_msg(data, reqData);
776 eap_aka_add_id_msg(data, buf);
777 data->prev_id = id;
778 }
779
780 return buf;
781 }
782
783
eap_aka_verify_mac(struct eap_aka_data * data,const struct wpabuf * req,const u8 * mac,const u8 * extra,size_t extra_len)784 static int eap_aka_verify_mac(struct eap_aka_data *data,
785 const struct wpabuf *req,
786 const u8 *mac, const u8 *extra,
787 size_t extra_len)
788 {
789 if (data->eap_method == EAP_TYPE_AKA_PRIME)
790 return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
791 extra_len);
792 return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
793 }
794
795
796 #ifdef EAP_AKA_PRIME
eap_aka_prime_kdf_select(struct eap_aka_data * data,u8 id,u16 kdf)797 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
798 u8 id, u16 kdf)
799 {
800 struct eap_sim_msg *msg;
801
802 data->kdf_negotiation = 1;
803 data->kdf = kdf;
804 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
805 "select)", id);
806 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
807 EAP_AKA_SUBTYPE_CHALLENGE);
808 wpa_printf(MSG_DEBUG, " AT_KDF");
809 eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
810 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
811 }
812
813
eap_aka_prime_kdf_neg(struct eap_aka_data * data,u8 id,struct eap_sim_attrs * attr)814 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
815 u8 id, struct eap_sim_attrs *attr)
816 {
817 size_t i;
818
819 for (i = 0; i < attr->kdf_count; i++) {
820 if (attr->kdf[i] == EAP_AKA_PRIME_KDF)
821 return eap_aka_prime_kdf_select(data, id,
822 EAP_AKA_PRIME_KDF);
823 }
824
825 /* No matching KDF found - fail authentication as if AUTN had been
826 * incorrect */
827 return eap_aka_authentication_reject(data, id);
828 }
829
830
eap_aka_prime_kdf_valid(struct eap_aka_data * data,struct eap_sim_attrs * attr)831 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
832 struct eap_sim_attrs *attr)
833 {
834 size_t i, j;
835
836 if (attr->kdf_count == 0)
837 return 0;
838
839 /* The only allowed (and required) duplication of a KDF is the addition
840 * of the selected KDF into the beginning of the list. */
841
842 if (data->kdf_negotiation) {
843 if (attr->kdf[0] != data->kdf) {
844 wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
845 "accept the selected KDF");
846 return 0;
847 }
848
849 for (i = 1; i < attr->kdf_count; i++) {
850 if (attr->kdf[i] == data->kdf)
851 break;
852 }
853 if (i == attr->kdf_count &&
854 attr->kdf_count < EAP_AKA_PRIME_KDF_MAX) {
855 wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
856 "duplicate the selected KDF");
857 return 0;
858 }
859
860 /* TODO: should check that the list is identical to the one
861 * used in the previous Challenge message apart from the added
862 * entry in the beginning. */
863 }
864
865 for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
866 for (j = i + 1; j < attr->kdf_count; j++) {
867 if (attr->kdf[i] == attr->kdf[j]) {
868 wpa_printf(MSG_WARNING, "EAP-AKA': The server "
869 "included a duplicated KDF");
870 return 0;
871 }
872 }
873 }
874
875 return 1;
876 }
877 #endif /* EAP_AKA_PRIME */
878
879
eap_aka_process_challenge(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)880 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
881 struct eap_aka_data *data,
882 u8 id,
883 const struct wpabuf *reqData,
884 struct eap_sim_attrs *attr)
885 {
886 const u8 *identity;
887 size_t identity_len;
888 int res;
889 struct eap_sim_attrs eattr;
890
891 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
892
893 if (attr->checkcode &&
894 eap_aka_verify_checkcode(data, attr->checkcode,
895 attr->checkcode_len)) {
896 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
897 "message");
898 return eap_aka_client_error(data, id,
899 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
900 }
901
902 #ifdef EAP_AKA_PRIME
903 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
904 if (!attr->kdf_input || attr->kdf_input_len == 0) {
905 wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
906 "did not include non-empty AT_KDF_INPUT");
907 /* Fail authentication as if AUTN had been incorrect */
908 return eap_aka_authentication_reject(data, id);
909 }
910 os_free(data->network_name);
911 data->network_name = os_malloc(attr->kdf_input_len);
912 if (data->network_name == NULL) {
913 wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
914 "storing Network Name");
915 return eap_aka_authentication_reject(data, id);
916 }
917 os_memcpy(data->network_name, attr->kdf_input,
918 attr->kdf_input_len);
919 data->network_name_len = attr->kdf_input_len;
920 wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
921 "(AT_KDF_INPUT)",
922 data->network_name, data->network_name_len);
923 /* TODO: check Network Name per 3GPP.33.402 */
924
925 if (!eap_aka_prime_kdf_valid(data, attr))
926 return eap_aka_authentication_reject(data, id);
927
928 if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
929 return eap_aka_prime_kdf_neg(data, id, attr);
930
931 data->kdf = EAP_AKA_PRIME_KDF;
932 wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
933 }
934
935 if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
936 u16 flags = WPA_GET_BE16(attr->bidding);
937 if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
938 eap_allowed_method(sm, EAP_VENDOR_IETF,
939 EAP_TYPE_AKA_PRIME)) {
940 wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
941 "AKA' to AKA detected");
942 /* Fail authentication as if AUTN had been incorrect */
943 return eap_aka_authentication_reject(data, id);
944 }
945 }
946 #endif /* EAP_AKA_PRIME */
947
948 data->reauth = 0;
949 if (!attr->mac || !attr->rand || !attr->autn) {
950 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
951 "did not include%s%s%s",
952 !attr->mac ? " AT_MAC" : "",
953 !attr->rand ? " AT_RAND" : "",
954 !attr->autn ? " AT_AUTN" : "");
955 return eap_aka_client_error(data, id,
956 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
957 }
958 os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
959 os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
960
961 res = eap_aka_umts_auth(sm, data);
962 if (res == -1) {
963 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
964 "failed (AUTN)");
965 return eap_aka_authentication_reject(data, id);
966 } else if (res == -2) {
967 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
968 "failed (AUTN seq# -> AUTS)");
969 return eap_aka_synchronization_failure(data, id);
970 } else if (res > 0) {
971 wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
972 return NULL;
973 } else if (res) {
974 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
975 return eap_aka_client_error(data, id,
976 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
977 }
978 #ifdef EAP_AKA_PRIME
979 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
980 /* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
981 * needed 6-octet SQN ^ AK for CK',IK' derivation */
982 u16 amf = WPA_GET_BE16(data->autn + 6);
983 if (!(amf & 0x8000)) {
984 wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
985 "not set (AMF=0x%4x)", amf);
986 return eap_aka_authentication_reject(data, id);
987 }
988 eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
989 data->autn,
990 data->network_name,
991 data->network_name_len);
992 }
993 #endif /* EAP_AKA_PRIME */
994 if (data->last_eap_identity) {
995 identity = data->last_eap_identity;
996 identity_len = data->last_eap_identity_len;
997 } else if (data->pseudonym) {
998 identity = data->pseudonym;
999 identity_len = data->pseudonym_len;
1000 } else
1001 identity = eap_get_config_identity(sm, &identity_len);
1002 wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
1003 "derivation", identity, identity_len);
1004 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1005 eap_aka_prime_derive_keys(identity, identity_len, data->ik,
1006 data->ck, data->k_encr, data->k_aut,
1007 data->k_re, data->msk, data->emsk);
1008 } else {
1009 eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
1010 data->mk);
1011 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
1012 data->msk, data->emsk);
1013 }
1014 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1015 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1016 "used invalid AT_MAC");
1017 return eap_aka_client_error(data, id,
1018 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1019 }
1020
1021 /* Old reauthentication identity must not be used anymore. In
1022 * other words, if no new identities are received, full
1023 * authentication will be used on next reauthentication (using
1024 * pseudonym identity or permanent identity). */
1025 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1026
1027 if (attr->encr_data) {
1028 u8 *decrypted;
1029 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1030 attr->encr_data_len, attr->iv,
1031 &eattr, 0);
1032 if (decrypted == NULL) {
1033 return eap_aka_client_error(
1034 data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1035 }
1036 eap_aka_learn_ids(sm, data, &eattr);
1037 os_free(decrypted);
1038 }
1039
1040 if (data->result_ind && attr->result_ind)
1041 data->use_result_ind = 1;
1042
1043 if (data->state != FAILURE) {
1044 eap_aka_state(data, data->use_result_ind ?
1045 RESULT_SUCCESS : SUCCESS);
1046 }
1047
1048 data->num_id_req = 0;
1049 data->num_notification = 0;
1050 /* RFC 4187 specifies that counter is initialized to one after
1051 * fullauth, but initializing it to zero makes it easier to implement
1052 * reauth verification. */
1053 data->counter = 0;
1054 return eap_aka_response_challenge(data, id);
1055 }
1056
1057
eap_aka_process_notification_reauth(struct eap_aka_data * data,struct eap_sim_attrs * attr)1058 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
1059 struct eap_sim_attrs *attr)
1060 {
1061 struct eap_sim_attrs eattr;
1062 u8 *decrypted;
1063
1064 if (attr->encr_data == NULL || attr->iv == NULL) {
1065 wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
1066 "reauth did not include encrypted data");
1067 return -1;
1068 }
1069
1070 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1071 attr->encr_data_len, attr->iv, &eattr,
1072 0);
1073 if (decrypted == NULL) {
1074 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1075 "data from notification message");
1076 return -1;
1077 }
1078
1079 if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
1080 wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
1081 "message does not match with counter in reauth "
1082 "message");
1083 os_free(decrypted);
1084 return -1;
1085 }
1086
1087 os_free(decrypted);
1088 return 0;
1089 }
1090
1091
eap_aka_process_notification_auth(struct eap_aka_data * data,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1092 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
1093 const struct wpabuf *reqData,
1094 struct eap_sim_attrs *attr)
1095 {
1096 if (attr->mac == NULL) {
1097 wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
1098 "Notification message");
1099 return -1;
1100 }
1101
1102 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1103 wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
1104 "used invalid AT_MAC");
1105 return -1;
1106 }
1107
1108 if (data->reauth &&
1109 eap_aka_process_notification_reauth(data, attr)) {
1110 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1111 "message after reauth");
1112 return -1;
1113 }
1114
1115 return 0;
1116 }
1117
1118
eap_aka_process_notification(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1119 static struct wpabuf * eap_aka_process_notification(
1120 struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1121 const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1122 {
1123 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1124 if (data->num_notification > 0) {
1125 wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1126 "rounds (only one allowed)");
1127 return eap_aka_client_error(data, id,
1128 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1129 }
1130 data->num_notification++;
1131 if (attr->notification == -1) {
1132 wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1133 "Notification message");
1134 return eap_aka_client_error(data, id,
1135 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1136 }
1137
1138 if ((attr->notification & 0x4000) == 0 &&
1139 eap_aka_process_notification_auth(data, reqData, attr)) {
1140 return eap_aka_client_error(data, id,
1141 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1142 }
1143
1144 eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1145 if (attr->notification >= 0 && attr->notification < 32768) {
1146 eap_aka_state(data, FAILURE);
1147 } else if (attr->notification == EAP_SIM_SUCCESS &&
1148 data->state == RESULT_SUCCESS)
1149 eap_aka_state(data, SUCCESS);
1150 return eap_aka_response_notification(data, id, attr->notification);
1151 }
1152
1153
eap_aka_process_reauthentication(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1154 static struct wpabuf * eap_aka_process_reauthentication(
1155 struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1156 const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1157 {
1158 struct eap_sim_attrs eattr;
1159 u8 *decrypted;
1160
1161 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1162
1163 if (attr->checkcode &&
1164 eap_aka_verify_checkcode(data, attr->checkcode,
1165 attr->checkcode_len)) {
1166 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1167 "message");
1168 return eap_aka_client_error(data, id,
1169 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1170 }
1171
1172 if (data->reauth_id == NULL) {
1173 wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1174 "reauthentication, but no reauth_id available");
1175 return eap_aka_client_error(data, id,
1176 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1177 }
1178
1179 data->reauth = 1;
1180 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1181 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1182 "did not have valid AT_MAC");
1183 return eap_aka_client_error(data, id,
1184 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1185 }
1186
1187 if (attr->encr_data == NULL || attr->iv == NULL) {
1188 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1189 "message did not include encrypted data");
1190 return eap_aka_client_error(data, id,
1191 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1192 }
1193
1194 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1195 attr->encr_data_len, attr->iv, &eattr,
1196 0);
1197 if (decrypted == NULL) {
1198 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1199 "data from reauthentication message");
1200 return eap_aka_client_error(data, id,
1201 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1202 }
1203
1204 if (eattr.nonce_s == NULL || eattr.counter < 0) {
1205 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1206 !eattr.nonce_s ? " AT_NONCE_S" : "",
1207 eattr.counter < 0 ? " AT_COUNTER" : "");
1208 os_free(decrypted);
1209 return eap_aka_client_error(data, id,
1210 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1211 }
1212
1213 if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1214 struct wpabuf *res;
1215 wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1216 "(%d <= %d)", eattr.counter, data->counter);
1217 data->counter_too_small = eattr.counter;
1218
1219 /* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1220 * reauth_id must not be used to start a new reauthentication.
1221 * However, since it was used in the last EAP-Response-Identity
1222 * packet, it has to saved for the following fullauth to be
1223 * used in MK derivation. */
1224 os_free(data->last_eap_identity);
1225 data->last_eap_identity = data->reauth_id;
1226 data->last_eap_identity_len = data->reauth_id_len;
1227 data->reauth_id = NULL;
1228 data->reauth_id_len = 0;
1229
1230 res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1231 os_free(decrypted);
1232
1233 return res;
1234 }
1235 data->counter = eattr.counter;
1236
1237 os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1238 wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1239 data->nonce_s, EAP_SIM_NONCE_S_LEN);
1240
1241 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1242 eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1243 data->reauth_id,
1244 data->reauth_id_len,
1245 data->nonce_s,
1246 data->msk, data->emsk);
1247 } else {
1248 eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1249 data->reauth_id_len,
1250 data->nonce_s, data->mk,
1251 data->msk, data->emsk);
1252 }
1253 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1254 eap_aka_learn_ids(sm, data, &eattr);
1255
1256 if (data->result_ind && attr->result_ind)
1257 data->use_result_ind = 1;
1258
1259 if (data->state != FAILURE) {
1260 eap_aka_state(data, data->use_result_ind ?
1261 RESULT_SUCCESS : SUCCESS);
1262 }
1263
1264 data->num_id_req = 0;
1265 data->num_notification = 0;
1266 if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1267 wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1268 "fast reauths performed - force fullauth");
1269 eap_aka_clear_identities(sm, data,
1270 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1271 }
1272 os_free(decrypted);
1273 return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1274 }
1275
1276
eap_aka_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)1277 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1278 struct eap_method_ret *ret,
1279 const struct wpabuf *reqData)
1280 {
1281 struct eap_aka_data *data = priv;
1282 const struct eap_hdr *req;
1283 u8 subtype, id;
1284 struct wpabuf *res;
1285 const u8 *pos;
1286 struct eap_sim_attrs attr;
1287 size_t len;
1288
1289 wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1290 if (eap_get_config_identity(sm, &len) == NULL) {
1291 wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1292 eap_sm_request_identity(sm);
1293 ret->ignore = TRUE;
1294 return NULL;
1295 }
1296
1297 pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1298 &len);
1299 if (pos == NULL || len < 3) {
1300 ret->ignore = TRUE;
1301 return NULL;
1302 }
1303 req = wpabuf_head(reqData);
1304 id = req->identifier;
1305 len = be_to_host16(req->length);
1306
1307 ret->ignore = FALSE;
1308 ret->methodState = METHOD_MAY_CONT;
1309 ret->decision = DECISION_FAIL;
1310 ret->allowNotifications = TRUE;
1311
1312 subtype = *pos++;
1313 wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1314 pos += 2; /* Reserved */
1315
1316 if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1317 data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1318 0)) {
1319 res = eap_aka_client_error(data, id,
1320 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1321 goto done;
1322 }
1323
1324 switch (subtype) {
1325 case EAP_AKA_SUBTYPE_IDENTITY:
1326 res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1327 break;
1328 case EAP_AKA_SUBTYPE_CHALLENGE:
1329 res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1330 break;
1331 case EAP_AKA_SUBTYPE_NOTIFICATION:
1332 res = eap_aka_process_notification(sm, data, id, reqData,
1333 &attr);
1334 break;
1335 case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1336 res = eap_aka_process_reauthentication(sm, data, id, reqData,
1337 &attr);
1338 break;
1339 case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1340 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1341 res = eap_aka_client_error(data, id,
1342 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1343 break;
1344 default:
1345 wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1346 res = eap_aka_client_error(data, id,
1347 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1348 break;
1349 }
1350
1351 done:
1352 if (data->state == FAILURE) {
1353 ret->decision = DECISION_FAIL;
1354 ret->methodState = METHOD_DONE;
1355 } else if (data->state == SUCCESS) {
1356 ret->decision = data->use_result_ind ?
1357 DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1358 /*
1359 * It is possible for the server to reply with AKA
1360 * Notification, so we must allow the method to continue and
1361 * not only accept EAP-Success at this point.
1362 */
1363 ret->methodState = data->use_result_ind ?
1364 METHOD_DONE : METHOD_MAY_CONT;
1365 } else if (data->state == RESULT_SUCCESS)
1366 ret->methodState = METHOD_CONT;
1367
1368 if (ret->methodState == METHOD_DONE) {
1369 ret->allowNotifications = FALSE;
1370 }
1371
1372 return res;
1373 }
1374
1375
eap_aka_has_reauth_data(struct eap_sm * sm,void * priv)1376 static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1377 {
1378 struct eap_aka_data *data = priv;
1379 return data->pseudonym || data->reauth_id;
1380 }
1381
1382
eap_aka_deinit_for_reauth(struct eap_sm * sm,void * priv)1383 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1384 {
1385 struct eap_aka_data *data = priv;
1386 eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1387 data->prev_id = -1;
1388 wpabuf_free(data->id_msgs);
1389 data->id_msgs = NULL;
1390 data->use_result_ind = 0;
1391 data->kdf_negotiation = 0;
1392 eap_aka_clear_keys(data, 1);
1393 }
1394
1395
eap_aka_init_for_reauth(struct eap_sm * sm,void * priv)1396 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1397 {
1398 struct eap_aka_data *data = priv;
1399 data->num_id_req = 0;
1400 data->num_notification = 0;
1401 eap_aka_state(data, CONTINUE);
1402 return priv;
1403 }
1404
1405
eap_aka_get_identity(struct eap_sm * sm,void * priv,size_t * len)1406 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1407 size_t *len)
1408 {
1409 struct eap_aka_data *data = priv;
1410
1411 if (data->reauth_id) {
1412 *len = data->reauth_id_len;
1413 return data->reauth_id;
1414 }
1415
1416 if (data->pseudonym) {
1417 *len = data->pseudonym_len;
1418 return data->pseudonym;
1419 }
1420
1421 return NULL;
1422 }
1423
1424
eap_aka_isKeyAvailable(struct eap_sm * sm,void * priv)1425 static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1426 {
1427 struct eap_aka_data *data = priv;
1428 return data->state == SUCCESS;
1429 }
1430
1431
eap_aka_getKey(struct eap_sm * sm,void * priv,size_t * len)1432 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1433 {
1434 struct eap_aka_data *data = priv;
1435 u8 *key;
1436
1437 if (data->state != SUCCESS)
1438 return NULL;
1439
1440 key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
1441 if (key == NULL)
1442 return NULL;
1443
1444 *len = EAP_SIM_KEYING_DATA_LEN;
1445 os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
1446
1447 return key;
1448 }
1449
1450
eap_aka_get_session_id(struct eap_sm * sm,void * priv,size_t * len)1451 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1452 {
1453 struct eap_aka_data *data = priv;
1454 u8 *id;
1455
1456 if (data->state != SUCCESS)
1457 return NULL;
1458
1459 *len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1460 id = os_malloc(*len);
1461 if (id == NULL)
1462 return NULL;
1463
1464 id[0] = data->eap_method;
1465 os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1466 os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn, EAP_AKA_AUTN_LEN);
1467 wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1468
1469 return id;
1470 }
1471
1472
eap_aka_get_emsk(struct eap_sm * sm,void * priv,size_t * len)1473 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1474 {
1475 struct eap_aka_data *data = priv;
1476 u8 *key;
1477
1478 if (data->state != SUCCESS)
1479 return NULL;
1480
1481 key = os_malloc(EAP_EMSK_LEN);
1482 if (key == NULL)
1483 return NULL;
1484
1485 *len = EAP_EMSK_LEN;
1486 os_memcpy(key, data->emsk, EAP_EMSK_LEN);
1487
1488 return key;
1489 }
1490
1491
eap_peer_aka_register(void)1492 int eap_peer_aka_register(void)
1493 {
1494 struct eap_method *eap;
1495
1496 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1497 EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1498 if (eap == NULL)
1499 return -1;
1500
1501 eap->init = eap_aka_init;
1502 eap->deinit = eap_aka_deinit;
1503 eap->process = eap_aka_process;
1504 eap->isKeyAvailable = eap_aka_isKeyAvailable;
1505 eap->getKey = eap_aka_getKey;
1506 eap->getSessionId = eap_aka_get_session_id;
1507 eap->has_reauth_data = eap_aka_has_reauth_data;
1508 eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1509 eap->init_for_reauth = eap_aka_init_for_reauth;
1510 eap->get_identity = eap_aka_get_identity;
1511 eap->get_emsk = eap_aka_get_emsk;
1512
1513 return eap_peer_method_register(eap);
1514 }
1515
1516
1517 #ifdef EAP_AKA_PRIME
eap_peer_aka_prime_register(void)1518 int eap_peer_aka_prime_register(void)
1519 {
1520 struct eap_method *eap;
1521
1522 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1523 EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1524 "AKA'");
1525 if (eap == NULL)
1526 return -1;
1527
1528 eap->init = eap_aka_prime_init;
1529 eap->deinit = eap_aka_deinit;
1530 eap->process = eap_aka_process;
1531 eap->isKeyAvailable = eap_aka_isKeyAvailable;
1532 eap->getKey = eap_aka_getKey;
1533 eap->getSessionId = eap_aka_get_session_id;
1534 eap->has_reauth_data = eap_aka_has_reauth_data;
1535 eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1536 eap->init_for_reauth = eap_aka_init_for_reauth;
1537 eap->get_identity = eap_aka_get_identity;
1538 eap->get_emsk = eap_aka_get_emsk;
1539
1540 return eap_peer_method_register(eap);
1541 }
1542 #endif /* EAP_AKA_PRIME */
1543