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 int use_pseudonym;
52 u8 eap_method;
53 u8 *network_name;
54 size_t network_name_len;
55 u16 kdf;
56 int kdf_negotiation;
57 };
58
59
60 #ifndef CONFIG_NO_STDOUT_DEBUG
eap_aka_state_txt(int state)61 static const char * eap_aka_state_txt(int state)
62 {
63 switch (state) {
64 case CONTINUE:
65 return "CONTINUE";
66 case RESULT_SUCCESS:
67 return "RESULT_SUCCESS";
68 case SUCCESS:
69 return "SUCCESS";
70 case FAILURE:
71 return "FAILURE";
72 default:
73 return "?";
74 }
75 }
76 #endif /* CONFIG_NO_STDOUT_DEBUG */
77
78
eap_aka_state(struct eap_aka_data * data,int state)79 static void eap_aka_state(struct eap_aka_data *data, int state)
80 {
81 wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
82 eap_aka_state_txt(data->state),
83 eap_aka_state_txt(state));
84 data->state = state;
85 }
86
87
eap_aka_init(struct eap_sm * sm)88 static void * eap_aka_init(struct eap_sm *sm)
89 {
90 struct eap_aka_data *data;
91 const char *phase1 = eap_get_config_phase1(sm);
92 struct eap_peer_config *config = eap_get_config(sm);
93
94 data = os_zalloc(sizeof(*data));
95 if (data == NULL)
96 return NULL;
97
98 data->eap_method = EAP_TYPE_AKA;
99
100 eap_aka_state(data, CONTINUE);
101 data->prev_id = -1;
102
103 data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
104
105 data->use_pseudonym = !sm->init_phase2;
106 if (config && config->anonymous_identity && data->use_pseudonym) {
107 data->pseudonym = os_malloc(config->anonymous_identity_len);
108 if (data->pseudonym) {
109 os_memcpy(data->pseudonym, config->anonymous_identity,
110 config->anonymous_identity_len);
111 data->pseudonym_len = config->anonymous_identity_len;
112 }
113 }
114
115 return data;
116 }
117
118
119 #ifdef EAP_AKA_PRIME
eap_aka_prime_init(struct eap_sm * sm)120 static void * eap_aka_prime_init(struct eap_sm *sm)
121 {
122 struct eap_aka_data *data = eap_aka_init(sm);
123 if (data == NULL)
124 return NULL;
125 data->eap_method = EAP_TYPE_AKA_PRIME;
126 return data;
127 }
128 #endif /* EAP_AKA_PRIME */
129
130
eap_aka_clear_keys(struct eap_aka_data * data,int reauth)131 static void eap_aka_clear_keys(struct eap_aka_data *data, int reauth)
132 {
133 if (!reauth) {
134 os_memset(data->mk, 0, EAP_SIM_MK_LEN);
135 os_memset(data->k_aut, 0, EAP_AKA_PRIME_K_AUT_LEN);
136 os_memset(data->k_encr, 0, EAP_SIM_K_ENCR_LEN);
137 os_memset(data->k_re, 0, EAP_AKA_PRIME_K_RE_LEN);
138 }
139 os_memset(data->msk, 0, EAP_SIM_KEYING_DATA_LEN);
140 os_memset(data->emsk, 0, EAP_EMSK_LEN);
141 os_memset(data->autn, 0, EAP_AKA_AUTN_LEN);
142 os_memset(data->auts, 0, EAP_AKA_AUTS_LEN);
143 }
144
145
eap_aka_deinit(struct eap_sm * sm,void * priv)146 static void eap_aka_deinit(struct eap_sm *sm, void *priv)
147 {
148 struct eap_aka_data *data = priv;
149 if (data) {
150 os_free(data->pseudonym);
151 os_free(data->reauth_id);
152 os_free(data->last_eap_identity);
153 wpabuf_free(data->id_msgs);
154 os_free(data->network_name);
155 eap_aka_clear_keys(data, 0);
156 os_free(data);
157 }
158 }
159
160
eap_aka_ext_sim_req(struct eap_sm * sm,struct eap_aka_data * data)161 static int eap_aka_ext_sim_req(struct eap_sm *sm, struct eap_aka_data *data)
162 {
163 char req[200], *pos, *end;
164
165 wpa_printf(MSG_DEBUG, "EAP-AKA: Use external USIM processing");
166 pos = req;
167 end = pos + sizeof(req);
168 pos += os_snprintf(pos, end - pos, "UMTS-AUTH");
169 pos += os_snprintf(pos, end - pos, ":");
170 pos += wpa_snprintf_hex(pos, end - pos, data->rand, EAP_AKA_RAND_LEN);
171 pos += os_snprintf(pos, end - pos, ":");
172 wpa_snprintf_hex(pos, end - pos, data->autn, EAP_AKA_AUTN_LEN);
173
174 eap_sm_request_sim(sm, req);
175 return 1;
176 }
177
178
eap_aka_ext_sim_result(struct eap_sm * sm,struct eap_aka_data * data,struct eap_peer_config * conf)179 static int eap_aka_ext_sim_result(struct eap_sm *sm, struct eap_aka_data *data,
180 struct eap_peer_config *conf)
181 {
182 char *resp, *pos;
183
184 wpa_printf(MSG_DEBUG,
185 "EAP-AKA: Use result from external USIM processing");
186
187 resp = conf->external_sim_resp;
188 conf->external_sim_resp = NULL;
189
190 if (os_strncmp(resp, "UMTS-AUTS:", 10) == 0) {
191 pos = resp + 10;
192 if (hexstr2bin(pos, data->auts, EAP_AKA_AUTS_LEN) < 0)
193 goto invalid;
194 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: AUTS", data->auts,
195 EAP_AKA_AUTS_LEN);
196 os_free(resp);
197 return -2;
198 }
199
200 if (os_strncmp(resp, "UMTS-AUTH:", 10) != 0) {
201 wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized external USIM processing response");
202 os_free(resp);
203 return -1;
204 }
205
206 pos = resp + 10;
207 wpa_hexdump(MSG_DEBUG, "EAP-AKA: RAND", data->rand, EAP_AKA_RAND_LEN);
208
209 if (hexstr2bin(pos, data->ik, EAP_AKA_IK_LEN) < 0)
210 goto invalid;
211 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, EAP_AKA_IK_LEN);
212 pos += EAP_AKA_IK_LEN * 2;
213 if (*pos != ':')
214 goto invalid;
215 pos++;
216
217 if (hexstr2bin(pos, data->ck, EAP_AKA_CK_LEN) < 0)
218 goto invalid;
219 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, EAP_AKA_CK_LEN);
220 pos += EAP_AKA_CK_LEN * 2;
221 if (*pos != ':')
222 goto invalid;
223 pos++;
224
225 data->res_len = os_strlen(pos) / 2;
226 if (data->res_len > EAP_AKA_RES_MAX_LEN) {
227 data->res_len = 0;
228 goto invalid;
229 }
230 if (hexstr2bin(pos, data->res, data->res_len) < 0)
231 goto invalid;
232 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: RES", data->res, data->res_len);
233
234 os_free(resp);
235 return 0;
236
237 invalid:
238 wpa_printf(MSG_DEBUG, "EAP-AKA: Invalid external USIM processing UMTS-AUTH response");
239 os_free(resp);
240 return -1;
241 }
242
243
eap_aka_umts_auth(struct eap_sm * sm,struct eap_aka_data * data)244 static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
245 {
246 struct eap_peer_config *conf;
247
248 wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
249
250 conf = eap_get_config(sm);
251 if (conf == NULL)
252 return -1;
253
254 if (sm->external_sim) {
255 if (conf->external_sim_resp)
256 return eap_aka_ext_sim_result(sm, data, conf);
257 else
258 return eap_aka_ext_sim_req(sm, data);
259 }
260
261 if (conf->pcsc) {
262 return scard_umts_auth(sm->scard_ctx, data->rand,
263 data->autn, data->res, &data->res_len,
264 data->ik, data->ck, data->auts);
265 }
266
267 #ifdef CONFIG_USIM_SIMULATOR
268 if (conf->password) {
269 u8 opc[16], k[16], sqn[6];
270 const char *pos;
271 wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
272 "implementation for UMTS authentication");
273 if (conf->password_len < 78) {
274 wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
275 "password");
276 return -1;
277 }
278 pos = (const char *) conf->password;
279 if (hexstr2bin(pos, k, 16))
280 return -1;
281 pos += 32;
282 if (*pos != ':')
283 return -1;
284 pos++;
285
286 if (hexstr2bin(pos, opc, 16))
287 return -1;
288 pos += 32;
289 if (*pos != ':')
290 return -1;
291 pos++;
292
293 if (hexstr2bin(pos, sqn, 6))
294 return -1;
295
296 return milenage_check(opc, k, sqn, data->rand, data->autn,
297 data->ik, data->ck,
298 data->res, &data->res_len, data->auts);
299 }
300 #endif /* CONFIG_USIM_SIMULATOR */
301
302 #ifdef CONFIG_USIM_HARDCODED
303 wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
304 "testing");
305
306 /* These hardcoded Kc and SRES values are used for testing.
307 * Could consider making them configurable. */
308 os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
309 data->res_len = EAP_AKA_RES_MAX_LEN;
310 os_memset(data->ik, '3', EAP_AKA_IK_LEN);
311 os_memset(data->ck, '4', EAP_AKA_CK_LEN);
312 {
313 u8 autn[EAP_AKA_AUTN_LEN];
314 os_memset(autn, '1', EAP_AKA_AUTN_LEN);
315 if (os_memcmp_const(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
316 wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
317 "with expected value");
318 return -1;
319 }
320 }
321 #if 0
322 {
323 static int test_resync = 1;
324 if (test_resync) {
325 /* Test Resynchronization */
326 test_resync = 0;
327 return -2;
328 }
329 }
330 #endif
331 return 0;
332
333 #else /* CONFIG_USIM_HARDCODED */
334
335 wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorithm "
336 "enabled");
337 return -1;
338
339 #endif /* CONFIG_USIM_HARDCODED */
340 }
341
342
343 #define CLEAR_PSEUDONYM 0x01
344 #define CLEAR_REAUTH_ID 0x02
345 #define CLEAR_EAP_ID 0x04
346
eap_aka_clear_identities(struct eap_sm * sm,struct eap_aka_data * data,int id)347 static void eap_aka_clear_identities(struct eap_sm *sm,
348 struct eap_aka_data *data, int id)
349 {
350 if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
351 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
352 os_free(data->pseudonym);
353 data->pseudonym = NULL;
354 data->pseudonym_len = 0;
355 if (data->use_pseudonym)
356 eap_set_anon_id(sm, NULL, 0);
357 }
358 if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
359 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
360 os_free(data->reauth_id);
361 data->reauth_id = NULL;
362 data->reauth_id_len = 0;
363 }
364 if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
365 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
366 os_free(data->last_eap_identity);
367 data->last_eap_identity = NULL;
368 data->last_eap_identity_len = 0;
369 }
370 }
371
372
eap_aka_learn_ids(struct eap_sm * sm,struct eap_aka_data * data,struct eap_sim_attrs * attr)373 static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
374 struct eap_sim_attrs *attr)
375 {
376 if (attr->next_pseudonym) {
377 const u8 *identity = NULL;
378 size_t identity_len = 0;
379 const u8 *realm = NULL;
380 size_t realm_len = 0;
381
382 wpa_hexdump_ascii(MSG_DEBUG,
383 "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
384 attr->next_pseudonym,
385 attr->next_pseudonym_len);
386 os_free(data->pseudonym);
387 /* Look for the realm of the permanent identity */
388 identity = eap_get_config_identity(sm, &identity_len);
389 if (identity) {
390 for (realm = identity, realm_len = identity_len;
391 realm_len > 0; realm_len--, realm++) {
392 if (*realm == '@')
393 break;
394 }
395 }
396 data->pseudonym = os_malloc(attr->next_pseudonym_len +
397 realm_len);
398 if (data->pseudonym == NULL) {
399 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
400 "next pseudonym");
401 data->pseudonym_len = 0;
402 return -1;
403 }
404 os_memcpy(data->pseudonym, attr->next_pseudonym,
405 attr->next_pseudonym_len);
406 if (realm_len) {
407 os_memcpy(data->pseudonym + attr->next_pseudonym_len,
408 realm, realm_len);
409 }
410 data->pseudonym_len = attr->next_pseudonym_len + realm_len;
411 if (data->use_pseudonym)
412 eap_set_anon_id(sm, data->pseudonym,
413 data->pseudonym_len);
414 }
415
416 if (attr->next_reauth_id) {
417 os_free(data->reauth_id);
418 data->reauth_id = os_malloc(attr->next_reauth_id_len);
419 if (data->reauth_id == NULL) {
420 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
421 "next reauth_id");
422 data->reauth_id_len = 0;
423 return -1;
424 }
425 os_memcpy(data->reauth_id, attr->next_reauth_id,
426 attr->next_reauth_id_len);
427 data->reauth_id_len = attr->next_reauth_id_len;
428 wpa_hexdump_ascii(MSG_DEBUG,
429 "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
430 data->reauth_id,
431 data->reauth_id_len);
432 }
433
434 return 0;
435 }
436
437
eap_aka_add_id_msg(struct eap_aka_data * data,const struct wpabuf * msg)438 static int eap_aka_add_id_msg(struct eap_aka_data *data,
439 const struct wpabuf *msg)
440 {
441 if (msg == NULL)
442 return -1;
443
444 if (data->id_msgs == NULL) {
445 data->id_msgs = wpabuf_dup(msg);
446 return data->id_msgs == NULL ? -1 : 0;
447 }
448
449 if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
450 return -1;
451 wpabuf_put_buf(data->id_msgs, msg);
452
453 return 0;
454 }
455
456
eap_aka_add_checkcode(struct eap_aka_data * data,struct eap_sim_msg * msg)457 static void eap_aka_add_checkcode(struct eap_aka_data *data,
458 struct eap_sim_msg *msg)
459 {
460 const u8 *addr;
461 size_t len;
462 u8 hash[SHA256_MAC_LEN];
463
464 wpa_printf(MSG_DEBUG, " AT_CHECKCODE");
465
466 if (data->id_msgs == NULL) {
467 /*
468 * No EAP-AKA/Identity packets were exchanged - send empty
469 * checkcode.
470 */
471 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
472 return;
473 }
474
475 /* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
476 addr = wpabuf_head(data->id_msgs);
477 len = wpabuf_len(data->id_msgs);
478 wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
479 #ifdef EAP_AKA_PRIME
480 if (data->eap_method == EAP_TYPE_AKA_PRIME)
481 sha256_vector(1, &addr, &len, hash);
482 else
483 #endif /* EAP_AKA_PRIME */
484 sha1_vector(1, &addr, &len, hash);
485
486 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
487 data->eap_method == EAP_TYPE_AKA_PRIME ?
488 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
489 }
490
491
eap_aka_verify_checkcode(struct eap_aka_data * data,const u8 * checkcode,size_t checkcode_len)492 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
493 const u8 *checkcode, size_t checkcode_len)
494 {
495 const u8 *addr;
496 size_t len;
497 u8 hash[SHA256_MAC_LEN];
498 size_t hash_len;
499
500 if (checkcode == NULL)
501 return -1;
502
503 if (data->id_msgs == NULL) {
504 if (checkcode_len != 0) {
505 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
506 "indicates that AKA/Identity messages were "
507 "used, but they were not");
508 return -1;
509 }
510 return 0;
511 }
512
513 hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
514 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
515
516 if (checkcode_len != hash_len) {
517 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
518 "indicates that AKA/Identity message were not "
519 "used, but they were");
520 return -1;
521 }
522
523 /* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
524 addr = wpabuf_head(data->id_msgs);
525 len = wpabuf_len(data->id_msgs);
526 #ifdef EAP_AKA_PRIME
527 if (data->eap_method == EAP_TYPE_AKA_PRIME)
528 sha256_vector(1, &addr, &len, hash);
529 else
530 #endif /* EAP_AKA_PRIME */
531 sha1_vector(1, &addr, &len, hash);
532
533 if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
534 wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
535 return -1;
536 }
537
538 return 0;
539 }
540
541
eap_aka_client_error(struct eap_aka_data * data,u8 id,int err)542 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
543 int err)
544 {
545 struct eap_sim_msg *msg;
546
547 eap_aka_state(data, FAILURE);
548 data->num_id_req = 0;
549 data->num_notification = 0;
550
551 wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
552 err);
553 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
554 EAP_AKA_SUBTYPE_CLIENT_ERROR);
555 eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
556 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
557 }
558
559
eap_aka_authentication_reject(struct eap_aka_data * data,u8 id)560 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
561 u8 id)
562 {
563 struct eap_sim_msg *msg;
564
565 eap_aka_state(data, FAILURE);
566 data->num_id_req = 0;
567 data->num_notification = 0;
568
569 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
570 "(id=%d)", id);
571 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
572 EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
573 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
574 }
575
576
eap_aka_synchronization_failure(struct eap_aka_data * data,u8 id)577 static struct wpabuf * eap_aka_synchronization_failure(
578 struct eap_aka_data *data, u8 id)
579 {
580 struct eap_sim_msg *msg;
581
582 data->num_id_req = 0;
583 data->num_notification = 0;
584
585 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
586 "(id=%d)", id);
587 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
588 EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
589 wpa_printf(MSG_DEBUG, " AT_AUTS");
590 eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
591 EAP_AKA_AUTS_LEN);
592 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
593 }
594
595
eap_aka_response_identity(struct eap_sm * sm,struct eap_aka_data * data,u8 id,enum eap_sim_id_req id_req)596 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
597 struct eap_aka_data *data,
598 u8 id,
599 enum eap_sim_id_req id_req)
600 {
601 const u8 *identity = NULL;
602 size_t identity_len = 0;
603 struct eap_sim_msg *msg;
604
605 data->reauth = 0;
606 if (id_req == ANY_ID && data->reauth_id) {
607 identity = data->reauth_id;
608 identity_len = data->reauth_id_len;
609 data->reauth = 1;
610 } else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
611 data->pseudonym) {
612 identity = data->pseudonym;
613 identity_len = data->pseudonym_len;
614 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
615 } else if (id_req != NO_ID_REQ) {
616 identity = eap_get_config_identity(sm, &identity_len);
617 if (identity) {
618 eap_aka_clear_identities(sm, data, CLEAR_PSEUDONYM |
619 CLEAR_REAUTH_ID);
620 }
621 }
622 if (id_req != NO_ID_REQ)
623 eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
624
625 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
626 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
627 EAP_AKA_SUBTYPE_IDENTITY);
628
629 if (identity) {
630 wpa_hexdump_ascii(MSG_DEBUG, " AT_IDENTITY",
631 identity, identity_len);
632 eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
633 identity, identity_len);
634 }
635
636 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
637 }
638
639
eap_aka_response_challenge(struct eap_aka_data * data,u8 id)640 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
641 u8 id)
642 {
643 struct eap_sim_msg *msg;
644
645 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
646 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
647 EAP_AKA_SUBTYPE_CHALLENGE);
648 wpa_printf(MSG_DEBUG, " AT_RES");
649 eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
650 data->res, data->res_len);
651 eap_aka_add_checkcode(data, msg);
652 if (data->use_result_ind) {
653 wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
654 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
655 }
656 wpa_printf(MSG_DEBUG, " AT_MAC");
657 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
658 return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, (u8 *) "",
659 0);
660 }
661
662
eap_aka_response_reauth(struct eap_aka_data * data,u8 id,int counter_too_small,const u8 * nonce_s)663 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
664 u8 id, int counter_too_small,
665 const u8 *nonce_s)
666 {
667 struct eap_sim_msg *msg;
668 unsigned int counter;
669
670 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
671 id);
672 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
673 EAP_AKA_SUBTYPE_REAUTHENTICATION);
674 wpa_printf(MSG_DEBUG, " AT_IV");
675 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
676 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
677
678 if (counter_too_small) {
679 wpa_printf(MSG_DEBUG, " *AT_COUNTER_TOO_SMALL");
680 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
681 counter = data->counter_too_small;
682 } else
683 counter = data->counter;
684
685 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", counter);
686 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
687
688 if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
689 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
690 "AT_ENCR_DATA");
691 eap_sim_msg_free(msg);
692 return NULL;
693 }
694 eap_aka_add_checkcode(data, msg);
695 if (data->use_result_ind) {
696 wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
697 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
698 }
699 wpa_printf(MSG_DEBUG, " AT_MAC");
700 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
701 return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, nonce_s,
702 EAP_SIM_NONCE_S_LEN);
703 }
704
705
eap_aka_response_notification(struct eap_aka_data * data,u8 id,u16 notification)706 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
707 u8 id, u16 notification)
708 {
709 struct eap_sim_msg *msg;
710 u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
711
712 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
713 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
714 EAP_AKA_SUBTYPE_NOTIFICATION);
715 if (k_aut && data->reauth) {
716 wpa_printf(MSG_DEBUG, " AT_IV");
717 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
718 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
719 EAP_SIM_AT_ENCR_DATA);
720 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", data->counter);
721 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
722 NULL, 0);
723 if (eap_sim_msg_add_encr_end(msg, data->k_encr,
724 EAP_SIM_AT_PADDING)) {
725 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
726 "AT_ENCR_DATA");
727 eap_sim_msg_free(msg);
728 return NULL;
729 }
730 }
731 if (k_aut) {
732 wpa_printf(MSG_DEBUG, " AT_MAC");
733 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
734 }
735 return eap_sim_msg_finish(msg, data->eap_method, k_aut, (u8 *) "", 0);
736 }
737
738
eap_aka_process_identity(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)739 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
740 struct eap_aka_data *data,
741 u8 id,
742 const struct wpabuf *reqData,
743 struct eap_sim_attrs *attr)
744 {
745 int id_error;
746 struct wpabuf *buf;
747
748 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
749
750 id_error = 0;
751 switch (attr->id_req) {
752 case NO_ID_REQ:
753 break;
754 case ANY_ID:
755 if (data->num_id_req > 0)
756 id_error++;
757 data->num_id_req++;
758 break;
759 case FULLAUTH_ID:
760 if (data->num_id_req > 1)
761 id_error++;
762 data->num_id_req++;
763 break;
764 case PERMANENT_ID:
765 if (data->num_id_req > 2)
766 id_error++;
767 data->num_id_req++;
768 break;
769 }
770 if (id_error) {
771 wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
772 "used within one authentication");
773 return eap_aka_client_error(data, id,
774 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
775 }
776
777 buf = eap_aka_response_identity(sm, data, id, attr->id_req);
778
779 if (data->prev_id != id) {
780 eap_aka_add_id_msg(data, reqData);
781 eap_aka_add_id_msg(data, buf);
782 data->prev_id = id;
783 }
784
785 return buf;
786 }
787
788
eap_aka_verify_mac(struct eap_aka_data * data,const struct wpabuf * req,const u8 * mac,const u8 * extra,size_t extra_len)789 static int eap_aka_verify_mac(struct eap_aka_data *data,
790 const struct wpabuf *req,
791 const u8 *mac, const u8 *extra,
792 size_t extra_len)
793 {
794 if (data->eap_method == EAP_TYPE_AKA_PRIME)
795 return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
796 extra_len);
797 return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
798 }
799
800
801 #ifdef EAP_AKA_PRIME
eap_aka_prime_kdf_select(struct eap_aka_data * data,u8 id,u16 kdf)802 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
803 u8 id, u16 kdf)
804 {
805 struct eap_sim_msg *msg;
806
807 data->kdf_negotiation = 1;
808 data->kdf = kdf;
809 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
810 "select)", id);
811 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
812 EAP_AKA_SUBTYPE_CHALLENGE);
813 wpa_printf(MSG_DEBUG, " AT_KDF");
814 eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
815 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
816 }
817
818
eap_aka_prime_kdf_neg(struct eap_aka_data * data,u8 id,struct eap_sim_attrs * attr)819 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
820 u8 id, struct eap_sim_attrs *attr)
821 {
822 size_t i;
823
824 for (i = 0; i < attr->kdf_count; i++) {
825 if (attr->kdf[i] == EAP_AKA_PRIME_KDF)
826 return eap_aka_prime_kdf_select(data, id,
827 EAP_AKA_PRIME_KDF);
828 }
829
830 /* No matching KDF found - fail authentication as if AUTN had been
831 * incorrect */
832 return eap_aka_authentication_reject(data, id);
833 }
834
835
eap_aka_prime_kdf_valid(struct eap_aka_data * data,struct eap_sim_attrs * attr)836 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
837 struct eap_sim_attrs *attr)
838 {
839 size_t i, j;
840
841 if (attr->kdf_count == 0)
842 return 0;
843
844 /* The only allowed (and required) duplication of a KDF is the addition
845 * of the selected KDF into the beginning of the list. */
846
847 if (data->kdf_negotiation) {
848 if (attr->kdf[0] != data->kdf) {
849 wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
850 "accept the selected KDF");
851 return 0;
852 }
853
854 for (i = 1; i < attr->kdf_count; i++) {
855 if (attr->kdf[i] == data->kdf)
856 break;
857 }
858 if (i == attr->kdf_count &&
859 attr->kdf_count < EAP_AKA_PRIME_KDF_MAX) {
860 wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
861 "duplicate the selected KDF");
862 return 0;
863 }
864
865 /* TODO: should check that the list is identical to the one
866 * used in the previous Challenge message apart from the added
867 * entry in the beginning. */
868 }
869
870 for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
871 for (j = i + 1; j < attr->kdf_count; j++) {
872 if (attr->kdf[i] == attr->kdf[j]) {
873 wpa_printf(MSG_WARNING, "EAP-AKA': The server "
874 "included a duplicated KDF");
875 return 0;
876 }
877 }
878 }
879
880 return 1;
881 }
882 #endif /* EAP_AKA_PRIME */
883
884
eap_aka_process_challenge(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)885 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
886 struct eap_aka_data *data,
887 u8 id,
888 const struct wpabuf *reqData,
889 struct eap_sim_attrs *attr)
890 {
891 const u8 *identity;
892 size_t identity_len;
893 int res;
894 struct eap_sim_attrs eattr;
895
896 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
897
898 if (attr->checkcode &&
899 eap_aka_verify_checkcode(data, attr->checkcode,
900 attr->checkcode_len)) {
901 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
902 "message");
903 return eap_aka_client_error(data, id,
904 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
905 }
906
907 #ifdef EAP_AKA_PRIME
908 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
909 if (!attr->kdf_input || attr->kdf_input_len == 0) {
910 wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
911 "did not include non-empty AT_KDF_INPUT");
912 /* Fail authentication as if AUTN had been incorrect */
913 return eap_aka_authentication_reject(data, id);
914 }
915 os_free(data->network_name);
916 data->network_name = os_malloc(attr->kdf_input_len);
917 if (data->network_name == NULL) {
918 wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
919 "storing Network Name");
920 return eap_aka_authentication_reject(data, id);
921 }
922 os_memcpy(data->network_name, attr->kdf_input,
923 attr->kdf_input_len);
924 data->network_name_len = attr->kdf_input_len;
925 wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
926 "(AT_KDF_INPUT)",
927 data->network_name, data->network_name_len);
928 /* TODO: check Network Name per 3GPP.33.402 */
929
930 if (!eap_aka_prime_kdf_valid(data, attr))
931 return eap_aka_authentication_reject(data, id);
932
933 if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
934 return eap_aka_prime_kdf_neg(data, id, attr);
935
936 data->kdf = EAP_AKA_PRIME_KDF;
937 wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
938 }
939
940 if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
941 u16 flags = WPA_GET_BE16(attr->bidding);
942 if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
943 eap_allowed_method(sm, EAP_VENDOR_IETF,
944 EAP_TYPE_AKA_PRIME)) {
945 wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
946 "AKA' to AKA detected");
947 /* Fail authentication as if AUTN had been incorrect */
948 return eap_aka_authentication_reject(data, id);
949 }
950 }
951 #endif /* EAP_AKA_PRIME */
952
953 data->reauth = 0;
954 if (!attr->mac || !attr->rand || !attr->autn) {
955 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
956 "did not include%s%s%s",
957 !attr->mac ? " AT_MAC" : "",
958 !attr->rand ? " AT_RAND" : "",
959 !attr->autn ? " AT_AUTN" : "");
960 return eap_aka_client_error(data, id,
961 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
962 }
963 os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
964 os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
965
966 res = eap_aka_umts_auth(sm, data);
967 if (res == -1) {
968 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
969 "failed (AUTN)");
970 return eap_aka_authentication_reject(data, id);
971 } else if (res == -2) {
972 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
973 "failed (AUTN seq# -> AUTS)");
974 return eap_aka_synchronization_failure(data, id);
975 } else if (res > 0) {
976 wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
977 return NULL;
978 } else if (res) {
979 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
980 return eap_aka_client_error(data, id,
981 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
982 }
983 #ifdef EAP_AKA_PRIME
984 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
985 /* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
986 * needed 6-octet SQN ^ AK for CK',IK' derivation */
987 u16 amf = WPA_GET_BE16(data->autn + 6);
988 if (!(amf & 0x8000)) {
989 wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
990 "not set (AMF=0x%4x)", amf);
991 return eap_aka_authentication_reject(data, id);
992 }
993 eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
994 data->autn,
995 data->network_name,
996 data->network_name_len);
997 }
998 #endif /* EAP_AKA_PRIME */
999 if (data->last_eap_identity) {
1000 identity = data->last_eap_identity;
1001 identity_len = data->last_eap_identity_len;
1002 } else if (data->pseudonym) {
1003 identity = data->pseudonym;
1004 identity_len = data->pseudonym_len;
1005 } else
1006 identity = eap_get_config_identity(sm, &identity_len);
1007 wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
1008 "derivation", identity, identity_len);
1009 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1010 eap_aka_prime_derive_keys(identity, identity_len, data->ik,
1011 data->ck, data->k_encr, data->k_aut,
1012 data->k_re, data->msk, data->emsk);
1013 } else {
1014 eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
1015 data->mk);
1016 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
1017 data->msk, data->emsk);
1018 }
1019 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1020 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1021 "used invalid AT_MAC");
1022 return eap_aka_client_error(data, id,
1023 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1024 }
1025
1026 /* Old reauthentication identity must not be used anymore. In
1027 * other words, if no new identities are received, full
1028 * authentication will be used on next reauthentication (using
1029 * pseudonym identity or permanent identity). */
1030 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1031
1032 if (attr->encr_data) {
1033 u8 *decrypted;
1034 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1035 attr->encr_data_len, attr->iv,
1036 &eattr, 0);
1037 if (decrypted == NULL) {
1038 return eap_aka_client_error(
1039 data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1040 }
1041 eap_aka_learn_ids(sm, data, &eattr);
1042 os_free(decrypted);
1043 }
1044
1045 if (data->result_ind && attr->result_ind)
1046 data->use_result_ind = 1;
1047
1048 if (data->state != FAILURE) {
1049 eap_aka_state(data, data->use_result_ind ?
1050 RESULT_SUCCESS : SUCCESS);
1051 }
1052
1053 data->num_id_req = 0;
1054 data->num_notification = 0;
1055 /* RFC 4187 specifies that counter is initialized to one after
1056 * fullauth, but initializing it to zero makes it easier to implement
1057 * reauth verification. */
1058 data->counter = 0;
1059 return eap_aka_response_challenge(data, id);
1060 }
1061
1062
eap_aka_process_notification_reauth(struct eap_aka_data * data,struct eap_sim_attrs * attr)1063 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
1064 struct eap_sim_attrs *attr)
1065 {
1066 struct eap_sim_attrs eattr;
1067 u8 *decrypted;
1068
1069 if (attr->encr_data == NULL || attr->iv == NULL) {
1070 wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
1071 "reauth did not include encrypted data");
1072 return -1;
1073 }
1074
1075 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1076 attr->encr_data_len, attr->iv, &eattr,
1077 0);
1078 if (decrypted == NULL) {
1079 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1080 "data from notification message");
1081 return -1;
1082 }
1083
1084 if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
1085 wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
1086 "message does not match with counter in reauth "
1087 "message");
1088 os_free(decrypted);
1089 return -1;
1090 }
1091
1092 os_free(decrypted);
1093 return 0;
1094 }
1095
1096
eap_aka_process_notification_auth(struct eap_aka_data * data,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1097 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
1098 const struct wpabuf *reqData,
1099 struct eap_sim_attrs *attr)
1100 {
1101 if (attr->mac == NULL) {
1102 wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
1103 "Notification message");
1104 return -1;
1105 }
1106
1107 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1108 wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
1109 "used invalid AT_MAC");
1110 return -1;
1111 }
1112
1113 if (data->reauth &&
1114 eap_aka_process_notification_reauth(data, attr)) {
1115 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1116 "message after reauth");
1117 return -1;
1118 }
1119
1120 return 0;
1121 }
1122
1123
eap_aka_process_notification(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1124 static struct wpabuf * eap_aka_process_notification(
1125 struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1126 const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1127 {
1128 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1129 if (data->num_notification > 0) {
1130 wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1131 "rounds (only one allowed)");
1132 return eap_aka_client_error(data, id,
1133 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1134 }
1135 data->num_notification++;
1136 if (attr->notification == -1) {
1137 wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1138 "Notification message");
1139 return eap_aka_client_error(data, id,
1140 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1141 }
1142
1143 if ((attr->notification & 0x4000) == 0 &&
1144 eap_aka_process_notification_auth(data, reqData, attr)) {
1145 return eap_aka_client_error(data, id,
1146 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1147 }
1148
1149 eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1150 if (attr->notification >= 0 && attr->notification < 32768) {
1151 eap_aka_state(data, FAILURE);
1152 } else if (attr->notification == EAP_SIM_SUCCESS &&
1153 data->state == RESULT_SUCCESS)
1154 eap_aka_state(data, SUCCESS);
1155 return eap_aka_response_notification(data, id, attr->notification);
1156 }
1157
1158
eap_aka_process_reauthentication(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1159 static struct wpabuf * eap_aka_process_reauthentication(
1160 struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1161 const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1162 {
1163 struct eap_sim_attrs eattr;
1164 u8 *decrypted;
1165
1166 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1167
1168 if (attr->checkcode &&
1169 eap_aka_verify_checkcode(data, attr->checkcode,
1170 attr->checkcode_len)) {
1171 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1172 "message");
1173 return eap_aka_client_error(data, id,
1174 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1175 }
1176
1177 if (data->reauth_id == NULL) {
1178 wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1179 "reauthentication, but no reauth_id available");
1180 return eap_aka_client_error(data, id,
1181 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1182 }
1183
1184 data->reauth = 1;
1185 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1186 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1187 "did not have valid AT_MAC");
1188 return eap_aka_client_error(data, id,
1189 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1190 }
1191
1192 if (attr->encr_data == NULL || attr->iv == NULL) {
1193 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1194 "message did not include encrypted data");
1195 return eap_aka_client_error(data, id,
1196 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1197 }
1198
1199 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1200 attr->encr_data_len, attr->iv, &eattr,
1201 0);
1202 if (decrypted == NULL) {
1203 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1204 "data from reauthentication message");
1205 return eap_aka_client_error(data, id,
1206 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1207 }
1208
1209 if (eattr.nonce_s == NULL || eattr.counter < 0) {
1210 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1211 !eattr.nonce_s ? " AT_NONCE_S" : "",
1212 eattr.counter < 0 ? " AT_COUNTER" : "");
1213 os_free(decrypted);
1214 return eap_aka_client_error(data, id,
1215 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1216 }
1217
1218 if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1219 struct wpabuf *res;
1220 wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1221 "(%d <= %d)", eattr.counter, data->counter);
1222 data->counter_too_small = eattr.counter;
1223
1224 /* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1225 * reauth_id must not be used to start a new reauthentication.
1226 * However, since it was used in the last EAP-Response-Identity
1227 * packet, it has to saved for the following fullauth to be
1228 * used in MK derivation. */
1229 os_free(data->last_eap_identity);
1230 data->last_eap_identity = data->reauth_id;
1231 data->last_eap_identity_len = data->reauth_id_len;
1232 data->reauth_id = NULL;
1233 data->reauth_id_len = 0;
1234
1235 res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1236 os_free(decrypted);
1237
1238 return res;
1239 }
1240 data->counter = eattr.counter;
1241
1242 os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1243 wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1244 data->nonce_s, EAP_SIM_NONCE_S_LEN);
1245
1246 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1247 eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1248 data->reauth_id,
1249 data->reauth_id_len,
1250 data->nonce_s,
1251 data->msk, data->emsk);
1252 } else {
1253 eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1254 data->reauth_id_len,
1255 data->nonce_s, data->mk,
1256 data->msk, data->emsk);
1257 }
1258 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1259 eap_aka_learn_ids(sm, data, &eattr);
1260
1261 if (data->result_ind && attr->result_ind)
1262 data->use_result_ind = 1;
1263
1264 if (data->state != FAILURE) {
1265 eap_aka_state(data, data->use_result_ind ?
1266 RESULT_SUCCESS : SUCCESS);
1267 }
1268
1269 data->num_id_req = 0;
1270 data->num_notification = 0;
1271 if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1272 wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1273 "fast reauths performed - force fullauth");
1274 eap_aka_clear_identities(sm, data,
1275 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1276 }
1277 os_free(decrypted);
1278 return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1279 }
1280
1281
eap_aka_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)1282 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1283 struct eap_method_ret *ret,
1284 const struct wpabuf *reqData)
1285 {
1286 struct eap_aka_data *data = priv;
1287 const struct eap_hdr *req;
1288 u8 subtype, id;
1289 struct wpabuf *res;
1290 const u8 *pos;
1291 struct eap_sim_attrs attr;
1292 size_t len;
1293
1294 wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1295 if (eap_get_config_identity(sm, &len) == NULL) {
1296 wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1297 eap_sm_request_identity(sm);
1298 ret->ignore = TRUE;
1299 return NULL;
1300 }
1301
1302 pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1303 &len);
1304 if (pos == NULL || len < 3) {
1305 ret->ignore = TRUE;
1306 return NULL;
1307 }
1308 req = wpabuf_head(reqData);
1309 id = req->identifier;
1310 len = be_to_host16(req->length);
1311
1312 ret->ignore = FALSE;
1313 ret->methodState = METHOD_MAY_CONT;
1314 ret->decision = DECISION_FAIL;
1315 ret->allowNotifications = TRUE;
1316
1317 subtype = *pos++;
1318 wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1319 pos += 2; /* Reserved */
1320
1321 if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1322 data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1323 0)) {
1324 res = eap_aka_client_error(data, id,
1325 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1326 goto done;
1327 }
1328
1329 switch (subtype) {
1330 case EAP_AKA_SUBTYPE_IDENTITY:
1331 res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1332 break;
1333 case EAP_AKA_SUBTYPE_CHALLENGE:
1334 res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1335 break;
1336 case EAP_AKA_SUBTYPE_NOTIFICATION:
1337 res = eap_aka_process_notification(sm, data, id, reqData,
1338 &attr);
1339 break;
1340 case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1341 res = eap_aka_process_reauthentication(sm, data, id, reqData,
1342 &attr);
1343 break;
1344 case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1345 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1346 res = eap_aka_client_error(data, id,
1347 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1348 break;
1349 default:
1350 wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1351 res = eap_aka_client_error(data, id,
1352 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1353 break;
1354 }
1355
1356 done:
1357 if (data->state == FAILURE) {
1358 ret->decision = DECISION_FAIL;
1359 ret->methodState = METHOD_DONE;
1360 } else if (data->state == SUCCESS) {
1361 ret->decision = data->use_result_ind ?
1362 DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1363 /*
1364 * It is possible for the server to reply with AKA
1365 * Notification, so we must allow the method to continue and
1366 * not only accept EAP-Success at this point.
1367 */
1368 ret->methodState = data->use_result_ind ?
1369 METHOD_DONE : METHOD_MAY_CONT;
1370 } else if (data->state == RESULT_SUCCESS)
1371 ret->methodState = METHOD_CONT;
1372
1373 if (ret->methodState == METHOD_DONE) {
1374 ret->allowNotifications = FALSE;
1375 }
1376
1377 return res;
1378 }
1379
1380
eap_aka_has_reauth_data(struct eap_sm * sm,void * priv)1381 static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1382 {
1383 struct eap_aka_data *data = priv;
1384 return data->pseudonym || data->reauth_id;
1385 }
1386
1387
eap_aka_deinit_for_reauth(struct eap_sm * sm,void * priv)1388 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1389 {
1390 struct eap_aka_data *data = priv;
1391 eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1392 data->prev_id = -1;
1393 wpabuf_free(data->id_msgs);
1394 data->id_msgs = NULL;
1395 data->use_result_ind = 0;
1396 data->kdf_negotiation = 0;
1397 eap_aka_clear_keys(data, 1);
1398 }
1399
1400
eap_aka_init_for_reauth(struct eap_sm * sm,void * priv)1401 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1402 {
1403 struct eap_aka_data *data = priv;
1404 data->num_id_req = 0;
1405 data->num_notification = 0;
1406 eap_aka_state(data, CONTINUE);
1407 return priv;
1408 }
1409
1410
eap_aka_get_identity(struct eap_sm * sm,void * priv,size_t * len)1411 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1412 size_t *len)
1413 {
1414 struct eap_aka_data *data = priv;
1415
1416 if (data->reauth_id) {
1417 *len = data->reauth_id_len;
1418 return data->reauth_id;
1419 }
1420
1421 if (data->pseudonym) {
1422 *len = data->pseudonym_len;
1423 return data->pseudonym;
1424 }
1425
1426 return NULL;
1427 }
1428
1429
eap_aka_isKeyAvailable(struct eap_sm * sm,void * priv)1430 static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1431 {
1432 struct eap_aka_data *data = priv;
1433 return data->state == SUCCESS;
1434 }
1435
1436
eap_aka_getKey(struct eap_sm * sm,void * priv,size_t * len)1437 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1438 {
1439 struct eap_aka_data *data = priv;
1440 u8 *key;
1441
1442 if (data->state != SUCCESS)
1443 return NULL;
1444
1445 key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
1446 if (key == NULL)
1447 return NULL;
1448
1449 *len = EAP_SIM_KEYING_DATA_LEN;
1450 os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
1451
1452 return key;
1453 }
1454
1455
eap_aka_get_session_id(struct eap_sm * sm,void * priv,size_t * len)1456 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1457 {
1458 struct eap_aka_data *data = priv;
1459 u8 *id;
1460
1461 if (data->state != SUCCESS)
1462 return NULL;
1463
1464 *len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1465 id = os_malloc(*len);
1466 if (id == NULL)
1467 return NULL;
1468
1469 id[0] = data->eap_method;
1470 os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1471 os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn, EAP_AKA_AUTN_LEN);
1472 wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1473
1474 return id;
1475 }
1476
1477
eap_aka_get_emsk(struct eap_sm * sm,void * priv,size_t * len)1478 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1479 {
1480 struct eap_aka_data *data = priv;
1481 u8 *key;
1482
1483 if (data->state != SUCCESS)
1484 return NULL;
1485
1486 key = os_malloc(EAP_EMSK_LEN);
1487 if (key == NULL)
1488 return NULL;
1489
1490 *len = EAP_EMSK_LEN;
1491 os_memcpy(key, data->emsk, EAP_EMSK_LEN);
1492
1493 return key;
1494 }
1495
1496
eap_peer_aka_register(void)1497 int eap_peer_aka_register(void)
1498 {
1499 struct eap_method *eap;
1500
1501 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1502 EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1503 if (eap == NULL)
1504 return -1;
1505
1506 eap->init = eap_aka_init;
1507 eap->deinit = eap_aka_deinit;
1508 eap->process = eap_aka_process;
1509 eap->isKeyAvailable = eap_aka_isKeyAvailable;
1510 eap->getKey = eap_aka_getKey;
1511 eap->getSessionId = eap_aka_get_session_id;
1512 eap->has_reauth_data = eap_aka_has_reauth_data;
1513 eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1514 eap->init_for_reauth = eap_aka_init_for_reauth;
1515 eap->get_identity = eap_aka_get_identity;
1516 eap->get_emsk = eap_aka_get_emsk;
1517
1518 return eap_peer_method_register(eap);
1519 }
1520
1521
1522 #ifdef EAP_AKA_PRIME
eap_peer_aka_prime_register(void)1523 int eap_peer_aka_prime_register(void)
1524 {
1525 struct eap_method *eap;
1526
1527 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1528 EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1529 "AKA'");
1530 if (eap == NULL)
1531 return -1;
1532
1533 eap->init = eap_aka_prime_init;
1534 eap->deinit = eap_aka_deinit;
1535 eap->process = eap_aka_process;
1536 eap->isKeyAvailable = eap_aka_isKeyAvailable;
1537 eap->getKey = eap_aka_getKey;
1538 eap->getSessionId = eap_aka_get_session_id;
1539 eap->has_reauth_data = eap_aka_has_reauth_data;
1540 eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1541 eap->init_for_reauth = eap_aka_init_for_reauth;
1542 eap->get_identity = eap_aka_get_identity;
1543 eap->get_emsk = eap_aka_get_emsk;
1544
1545 return eap_peer_method_register(eap);
1546 }
1547 #endif /* EAP_AKA_PRIME */
1548