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 u16 last_kdf_attrs[EAP_AKA_PRIME_KDF_MAX];
58 size_t last_kdf_count;
59 int error_code;
60 int anonymous_flag;
61 };
62
63
64 #ifndef CONFIG_NO_STDOUT_DEBUG
eap_aka_state_txt(int state)65 static const char * eap_aka_state_txt(int state)
66 {
67 switch (state) {
68 case CONTINUE:
69 return "CONTINUE";
70 case RESULT_SUCCESS:
71 return "RESULT_SUCCESS";
72 case SUCCESS:
73 return "SUCCESS";
74 case FAILURE:
75 return "FAILURE";
76 default:
77 return "?";
78 }
79 }
80 #endif /* CONFIG_NO_STDOUT_DEBUG */
81
82
eap_aka_state(struct eap_aka_data * data,int state)83 static void eap_aka_state(struct eap_aka_data *data, int state)
84 {
85 wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
86 eap_aka_state_txt(data->state),
87 eap_aka_state_txt(state));
88 data->state = state;
89 }
90
91
eap_aka_init(struct eap_sm * sm)92 static void * eap_aka_init(struct eap_sm *sm)
93 {
94 struct eap_aka_data *data;
95 const char *phase1 = eap_get_config_phase1(sm);
96 struct eap_peer_config *config = eap_get_config(sm);
97 static const char *anonymous_id_prefix = "anonymous@";
98
99 data = os_zalloc(sizeof(*data));
100 if (data == NULL)
101 return NULL;
102
103 data->eap_method = EAP_TYPE_AKA;
104
105 /* Zero is a valid error code, so we need to initialize */
106 data->error_code = NO_EAP_METHOD_ERROR;
107
108 eap_aka_state(data, CONTINUE);
109 data->prev_id = -1;
110
111 data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
112 data->anonymous_flag = 0;
113
114 data->use_pseudonym = !sm->init_phase2;
115 if (config && config->anonymous_identity && data->use_pseudonym) {
116 data->pseudonym = os_malloc(config->anonymous_identity_len);
117 if (data->pseudonym) {
118 os_memcpy(data->pseudonym, config->anonymous_identity,
119 config->anonymous_identity_len);
120 data->pseudonym_len = config->anonymous_identity_len;
121 if (data->pseudonym_len > os_strlen(anonymous_id_prefix) &&
122 !os_memcmp(data->pseudonym, anonymous_id_prefix,
123 os_strlen(anonymous_id_prefix))) {
124 data->anonymous_flag = 1;
125 wpa_printf(MSG_DEBUG,
126 "EAP-AKA: Setting anonymous@realm flag");
127 }
128 }
129 }
130
131 return data;
132 }
133
134
135 #ifdef EAP_AKA_PRIME
eap_aka_prime_init(struct eap_sm * sm)136 static void * eap_aka_prime_init(struct eap_sm *sm)
137 {
138 struct eap_aka_data *data = eap_aka_init(sm);
139 if (data == NULL)
140 return NULL;
141 data->eap_method = EAP_TYPE_AKA_PRIME;
142 return data;
143 }
144 #endif /* EAP_AKA_PRIME */
145
146
eap_aka_clear_keys(struct eap_aka_data * data,int reauth)147 static void eap_aka_clear_keys(struct eap_aka_data *data, int reauth)
148 {
149 if (!reauth) {
150 os_memset(data->mk, 0, EAP_SIM_MK_LEN);
151 os_memset(data->k_aut, 0, EAP_AKA_PRIME_K_AUT_LEN);
152 os_memset(data->k_encr, 0, EAP_SIM_K_ENCR_LEN);
153 os_memset(data->k_re, 0, EAP_AKA_PRIME_K_RE_LEN);
154 }
155 os_memset(data->msk, 0, EAP_SIM_KEYING_DATA_LEN);
156 os_memset(data->emsk, 0, EAP_EMSK_LEN);
157 os_memset(data->autn, 0, EAP_AKA_AUTN_LEN);
158 os_memset(data->auts, 0, EAP_AKA_AUTS_LEN);
159 }
160
161
eap_aka_deinit(struct eap_sm * sm,void * priv)162 static void eap_aka_deinit(struct eap_sm *sm, void *priv)
163 {
164 struct eap_aka_data *data = priv;
165 if (data) {
166 os_free(data->pseudonym);
167 os_free(data->reauth_id);
168 os_free(data->last_eap_identity);
169 wpabuf_free(data->id_msgs);
170 os_free(data->network_name);
171 eap_aka_clear_keys(data, 0);
172 os_free(data);
173 }
174 }
175
176
eap_aka_ext_sim_req(struct eap_sm * sm,struct eap_aka_data * data)177 static int eap_aka_ext_sim_req(struct eap_sm *sm, struct eap_aka_data *data)
178 {
179 char req[200], *pos, *end;
180
181 wpa_printf(MSG_DEBUG, "EAP-AKA: Use external USIM processing");
182 pos = req;
183 end = pos + sizeof(req);
184 pos += os_snprintf(pos, end - pos, "UMTS-AUTH");
185 pos += os_snprintf(pos, end - pos, ":");
186 pos += wpa_snprintf_hex(pos, end - pos, data->rand, EAP_AKA_RAND_LEN);
187 pos += os_snprintf(pos, end - pos, ":");
188 wpa_snprintf_hex(pos, end - pos, data->autn, EAP_AKA_AUTN_LEN);
189
190 eap_sm_request_sim(sm, req);
191 return 1;
192 }
193
194
eap_aka_ext_sim_result(struct eap_sm * sm,struct eap_aka_data * data,struct eap_peer_config * conf)195 static int eap_aka_ext_sim_result(struct eap_sm *sm, struct eap_aka_data *data,
196 struct eap_peer_config *conf)
197 {
198 char *resp, *pos;
199
200 wpa_printf(MSG_DEBUG,
201 "EAP-AKA: Use result from external USIM processing");
202
203 resp = conf->external_sim_resp;
204 conf->external_sim_resp = NULL;
205
206 if (os_strncmp(resp, "UMTS-AUTS:", 10) == 0) {
207 pos = resp + 10;
208 if (hexstr2bin(pos, data->auts, EAP_AKA_AUTS_LEN) < 0)
209 goto invalid;
210 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: AUTS", data->auts,
211 EAP_AKA_AUTS_LEN);
212 os_free(resp);
213 return -2;
214 }
215
216 if (os_strncmp(resp, "UMTS-AUTH:", 10) != 0) {
217 wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized external USIM processing response");
218 os_free(resp);
219 return -1;
220 }
221
222 pos = resp + 10;
223 wpa_hexdump(MSG_DEBUG, "EAP-AKA: RAND", data->rand, EAP_AKA_RAND_LEN);
224
225 if (hexstr2bin(pos, data->ik, EAP_AKA_IK_LEN) < 0)
226 goto invalid;
227 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, EAP_AKA_IK_LEN);
228 pos += EAP_AKA_IK_LEN * 2;
229 if (*pos != ':')
230 goto invalid;
231 pos++;
232
233 if (hexstr2bin(pos, data->ck, EAP_AKA_CK_LEN) < 0)
234 goto invalid;
235 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, EAP_AKA_CK_LEN);
236 pos += EAP_AKA_CK_LEN * 2;
237 if (*pos != ':')
238 goto invalid;
239 pos++;
240
241 data->res_len = os_strlen(pos) / 2;
242 if (data->res_len > EAP_AKA_RES_MAX_LEN) {
243 data->res_len = 0;
244 goto invalid;
245 }
246 if (hexstr2bin(pos, data->res, data->res_len) < 0)
247 goto invalid;
248 wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: RES", data->res, data->res_len);
249
250 os_free(resp);
251 return 0;
252
253 invalid:
254 wpa_printf(MSG_DEBUG, "EAP-AKA: Invalid external USIM processing UMTS-AUTH response");
255 os_free(resp);
256 return -1;
257 }
258
259
eap_aka_umts_auth(struct eap_sm * sm,struct eap_aka_data * data)260 static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
261 {
262 struct eap_peer_config *conf;
263
264 wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
265
266 conf = eap_get_config(sm);
267 if (conf == NULL)
268 return -1;
269
270 if (sm->external_sim) {
271 if (conf->external_sim_resp)
272 return eap_aka_ext_sim_result(sm, data, conf);
273 else
274 return eap_aka_ext_sim_req(sm, data);
275 }
276
277 if (conf->pcsc) {
278 return scard_umts_auth(sm->scard_ctx, data->rand,
279 data->autn, data->res, &data->res_len,
280 data->ik, data->ck, data->auts);
281 }
282
283 #ifdef CONFIG_USIM_SIMULATOR
284 if (conf->password) {
285 u8 opc[16], k[16], sqn[6];
286 const char *pos;
287 wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
288 "implementation for UMTS authentication");
289 if (conf->password_len < 78) {
290 wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
291 "password");
292 return -1;
293 }
294 pos = (const char *) conf->password;
295 if (hexstr2bin(pos, k, 16))
296 return -1;
297 pos += 32;
298 if (*pos != ':')
299 return -1;
300 pos++;
301
302 if (hexstr2bin(pos, opc, 16))
303 return -1;
304 pos += 32;
305 if (*pos != ':')
306 return -1;
307 pos++;
308
309 if (hexstr2bin(pos, sqn, 6))
310 return -1;
311
312 return milenage_check(opc, k, sqn, data->rand, data->autn,
313 data->ik, data->ck,
314 data->res, &data->res_len, data->auts);
315 }
316 #endif /* CONFIG_USIM_SIMULATOR */
317
318 #ifdef CONFIG_USIM_HARDCODED
319 wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
320 "testing");
321
322 /* These hardcoded Kc and SRES values are used for testing.
323 * Could consider making them configurable. */
324 os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
325 data->res_len = EAP_AKA_RES_MAX_LEN;
326 os_memset(data->ik, '3', EAP_AKA_IK_LEN);
327 os_memset(data->ck, '4', EAP_AKA_CK_LEN);
328 {
329 u8 autn[EAP_AKA_AUTN_LEN];
330 os_memset(autn, '1', EAP_AKA_AUTN_LEN);
331 if (os_memcmp_const(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
332 wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
333 "with expected value");
334 return -1;
335 }
336 }
337 #if 0
338 {
339 static int test_resync = 1;
340 if (test_resync) {
341 /* Test Resynchronization */
342 test_resync = 0;
343 return -2;
344 }
345 }
346 #endif
347 return 0;
348
349 #else /* CONFIG_USIM_HARDCODED */
350
351 wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorithm "
352 "enabled");
353 return -1;
354
355 #endif /* CONFIG_USIM_HARDCODED */
356 }
357
358
359 #define CLEAR_PSEUDONYM 0x01
360 #define CLEAR_REAUTH_ID 0x02
361 #define CLEAR_EAP_ID 0x04
362
eap_aka_clear_identities(struct eap_sm * sm,struct eap_aka_data * data,int id)363 static void eap_aka_clear_identities(struct eap_sm *sm,
364 struct eap_aka_data *data, int id)
365 {
366 if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
367 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
368 os_free(data->pseudonym);
369 data->pseudonym = NULL;
370 data->pseudonym_len = 0;
371 if (data->use_pseudonym)
372 eap_set_anon_id(sm, NULL, 0);
373 }
374 if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
375 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
376 os_free(data->reauth_id);
377 data->reauth_id = NULL;
378 data->reauth_id_len = 0;
379 }
380 if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
381 wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
382 os_free(data->last_eap_identity);
383 data->last_eap_identity = NULL;
384 data->last_eap_identity_len = 0;
385 }
386 }
387
388
eap_aka_learn_ids(struct eap_sm * sm,struct eap_aka_data * data,struct eap_sim_attrs * attr)389 static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
390 struct eap_sim_attrs *attr)
391 {
392 if (attr->next_pseudonym) {
393 const u8 *identity = NULL;
394 size_t identity_len = 0;
395 const u8 *realm = NULL;
396 size_t realm_len = 0;
397
398 wpa_hexdump_ascii(MSG_DEBUG,
399 "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
400 attr->next_pseudonym,
401 attr->next_pseudonym_len);
402 os_free(data->pseudonym);
403 /* Look for the realm of the permanent identity */
404 identity = eap_get_config_identity(sm, &identity_len);
405 if (identity) {
406 for (realm = identity, realm_len = identity_len;
407 realm_len > 0; realm_len--, realm++) {
408 if (*realm == '@')
409 break;
410 }
411 }
412 data->pseudonym = os_malloc(attr->next_pseudonym_len +
413 realm_len);
414 if (data->pseudonym == NULL) {
415 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
416 "next pseudonym");
417 data->pseudonym_len = 0;
418 return -1;
419 }
420 os_memcpy(data->pseudonym, attr->next_pseudonym,
421 attr->next_pseudonym_len);
422 if (realm_len) {
423 os_memcpy(data->pseudonym + attr->next_pseudonym_len,
424 realm, realm_len);
425 }
426 data->pseudonym_len = attr->next_pseudonym_len + realm_len;
427 if (data->use_pseudonym)
428 eap_set_anon_id(sm, data->pseudonym,
429 data->pseudonym_len);
430 data->anonymous_flag = 0;
431 }
432
433 if (attr->next_reauth_id) {
434 os_free(data->reauth_id);
435 data->reauth_id = os_memdup(attr->next_reauth_id,
436 attr->next_reauth_id_len);
437 if (data->reauth_id == NULL) {
438 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
439 "next reauth_id");
440 data->reauth_id_len = 0;
441 return -1;
442 }
443 data->reauth_id_len = attr->next_reauth_id_len;
444 wpa_hexdump_ascii(MSG_DEBUG,
445 "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
446 data->reauth_id,
447 data->reauth_id_len);
448 }
449
450 return 0;
451 }
452
453
eap_aka_add_id_msg(struct eap_aka_data * data,const struct wpabuf * msg)454 static int eap_aka_add_id_msg(struct eap_aka_data *data,
455 const struct wpabuf *msg)
456 {
457 if (msg == NULL)
458 return -1;
459
460 if (data->id_msgs == NULL) {
461 data->id_msgs = wpabuf_dup(msg);
462 return data->id_msgs == NULL ? -1 : 0;
463 }
464
465 if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
466 return -1;
467 wpabuf_put_buf(data->id_msgs, msg);
468
469 return 0;
470 }
471
472
eap_aka_add_checkcode(struct eap_aka_data * data,struct eap_sim_msg * msg)473 static void eap_aka_add_checkcode(struct eap_aka_data *data,
474 struct eap_sim_msg *msg)
475 {
476 const u8 *addr;
477 size_t len;
478 u8 hash[SHA256_MAC_LEN];
479
480 wpa_printf(MSG_DEBUG, " AT_CHECKCODE");
481
482 if (data->id_msgs == NULL) {
483 /*
484 * No EAP-AKA/Identity packets were exchanged - send empty
485 * checkcode.
486 */
487 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
488 return;
489 }
490
491 /* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
492 addr = wpabuf_head(data->id_msgs);
493 len = wpabuf_len(data->id_msgs);
494 wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
495 #ifdef EAP_AKA_PRIME
496 if (data->eap_method == EAP_TYPE_AKA_PRIME)
497 sha256_vector(1, &addr, &len, hash);
498 else
499 #endif /* EAP_AKA_PRIME */
500 sha1_vector(1, &addr, &len, hash);
501
502 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
503 data->eap_method == EAP_TYPE_AKA_PRIME ?
504 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
505 }
506
507
eap_aka_verify_checkcode(struct eap_aka_data * data,const u8 * checkcode,size_t checkcode_len)508 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
509 const u8 *checkcode, size_t checkcode_len)
510 {
511 const u8 *addr;
512 size_t len;
513 u8 hash[SHA256_MAC_LEN];
514 size_t hash_len;
515
516 if (checkcode == NULL)
517 return -1;
518
519 if (data->id_msgs == NULL) {
520 if (checkcode_len != 0) {
521 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
522 "indicates that AKA/Identity messages were "
523 "used, but they were not");
524 return -1;
525 }
526 return 0;
527 }
528
529 hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
530 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
531
532 if (checkcode_len != hash_len) {
533 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
534 "indicates that AKA/Identity message were not "
535 "used, but they were");
536 return -1;
537 }
538
539 /* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
540 addr = wpabuf_head(data->id_msgs);
541 len = wpabuf_len(data->id_msgs);
542 #ifdef EAP_AKA_PRIME
543 if (data->eap_method == EAP_TYPE_AKA_PRIME)
544 sha256_vector(1, &addr, &len, hash);
545 else
546 #endif /* EAP_AKA_PRIME */
547 sha1_vector(1, &addr, &len, hash);
548
549 if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
550 wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
551 return -1;
552 }
553
554 return 0;
555 }
556
557
eap_aka_client_error(struct eap_aka_data * data,u8 id,int err)558 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
559 int err)
560 {
561 struct eap_sim_msg *msg;
562
563 eap_aka_state(data, FAILURE);
564 data->num_id_req = 0;
565 data->num_notification = 0;
566
567 wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
568 err);
569 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
570 EAP_AKA_SUBTYPE_CLIENT_ERROR);
571 eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
572 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
573 }
574
575
eap_aka_authentication_reject(struct eap_aka_data * data,u8 id)576 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
577 u8 id)
578 {
579 struct eap_sim_msg *msg;
580
581 eap_aka_state(data, FAILURE);
582 data->num_id_req = 0;
583 data->num_notification = 0;
584
585 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
586 "(id=%d)", id);
587 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
588 EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
589 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
590 }
591
592
eap_aka_synchronization_failure(struct eap_aka_data * data,u8 id,struct eap_sim_attrs * attr)593 static struct wpabuf * eap_aka_synchronization_failure(
594 struct eap_aka_data *data, u8 id, struct eap_sim_attrs *attr)
595 {
596 struct eap_sim_msg *msg;
597
598 data->num_id_req = 0;
599 data->num_notification = 0;
600
601 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
602 "(id=%d)", id);
603 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
604 EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
605 wpa_printf(MSG_DEBUG, " AT_AUTS");
606 eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
607 EAP_AKA_AUTS_LEN);
608 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
609 size_t i;
610
611 for (i = 0; i < attr->kdf_count; i++) {
612 wpa_printf(MSG_DEBUG, " AT_KDF");
613 eap_sim_msg_add(msg, EAP_SIM_AT_KDF, attr->kdf[i],
614 NULL, 0);
615 }
616 }
617 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
618 }
619
620
eap_aka_response_identity(struct eap_sm * sm,struct eap_aka_data * data,u8 id,enum eap_sim_id_req id_req)621 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
622 struct eap_aka_data *data,
623 u8 id,
624 enum eap_sim_id_req id_req)
625 {
626 const u8 *identity = NULL;
627 size_t identity_len = 0;
628 struct eap_sim_msg *msg;
629
630 data->reauth = 0;
631 if (id_req == ANY_ID && data->reauth_id) {
632 identity = data->reauth_id;
633 identity_len = data->reauth_id_len;
634 data->reauth = 1;
635 } else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
636 data->pseudonym && !data->anonymous_flag) {
637 identity = data->pseudonym;
638 identity_len = data->pseudonym_len;
639 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
640 } else if (id_req != NO_ID_REQ) {
641 identity = eap_get_config_identity(sm, &identity_len);
642 if (identity) {
643 eap_aka_clear_identities(sm, data, CLEAR_PSEUDONYM |
644 CLEAR_REAUTH_ID);
645 }
646 }
647 if (id_req != NO_ID_REQ)
648 eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
649
650 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
651 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
652 EAP_AKA_SUBTYPE_IDENTITY);
653
654 if (identity) {
655 wpa_hexdump_ascii(MSG_DEBUG, " AT_IDENTITY",
656 identity, identity_len);
657 eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
658 identity, identity_len);
659 }
660
661 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
662 }
663
664
eap_aka_response_challenge(struct eap_aka_data * data,u8 id)665 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
666 u8 id)
667 {
668 struct eap_sim_msg *msg;
669
670 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
671 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
672 EAP_AKA_SUBTYPE_CHALLENGE);
673 wpa_printf(MSG_DEBUG, " AT_RES");
674 eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
675 data->res, data->res_len);
676 eap_aka_add_checkcode(data, msg);
677 if (data->use_result_ind) {
678 wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
679 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
680 }
681 wpa_printf(MSG_DEBUG, " AT_MAC");
682 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
683 return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, (u8 *) "",
684 0);
685 }
686
687
eap_aka_response_reauth(struct eap_aka_data * data,u8 id,int counter_too_small,const u8 * nonce_s)688 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
689 u8 id, int counter_too_small,
690 const u8 *nonce_s)
691 {
692 struct eap_sim_msg *msg;
693 unsigned int counter;
694
695 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
696 id);
697 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
698 EAP_AKA_SUBTYPE_REAUTHENTICATION);
699 wpa_printf(MSG_DEBUG, " AT_IV");
700 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
701 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
702
703 if (counter_too_small) {
704 wpa_printf(MSG_DEBUG, " *AT_COUNTER_TOO_SMALL");
705 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
706 counter = data->counter_too_small;
707 } else
708 counter = data->counter;
709
710 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", counter);
711 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
712
713 if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
714 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
715 "AT_ENCR_DATA");
716 eap_sim_msg_free(msg);
717 return NULL;
718 }
719 eap_aka_add_checkcode(data, msg);
720 if (data->use_result_ind) {
721 wpa_printf(MSG_DEBUG, " AT_RESULT_IND");
722 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
723 }
724 wpa_printf(MSG_DEBUG, " AT_MAC");
725 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
726 return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, nonce_s,
727 EAP_SIM_NONCE_S_LEN);
728 }
729
730
eap_aka_response_notification(struct eap_aka_data * data,u8 id,u16 notification)731 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
732 u8 id, u16 notification)
733 {
734 struct eap_sim_msg *msg;
735 u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
736
737 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
738 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
739 EAP_AKA_SUBTYPE_NOTIFICATION);
740 if (k_aut && data->reauth) {
741 wpa_printf(MSG_DEBUG, " AT_IV");
742 wpa_printf(MSG_DEBUG, " AT_ENCR_DATA");
743 eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
744 EAP_SIM_AT_ENCR_DATA);
745 wpa_printf(MSG_DEBUG, " *AT_COUNTER %d", data->counter);
746 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
747 NULL, 0);
748 if (eap_sim_msg_add_encr_end(msg, data->k_encr,
749 EAP_SIM_AT_PADDING)) {
750 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
751 "AT_ENCR_DATA");
752 eap_sim_msg_free(msg);
753 return NULL;
754 }
755 }
756 if (k_aut) {
757 wpa_printf(MSG_DEBUG, " AT_MAC");
758 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
759 }
760 return eap_sim_msg_finish(msg, data->eap_method, k_aut, (u8 *) "", 0);
761 }
762
763
eap_aka_process_identity(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)764 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
765 struct eap_aka_data *data,
766 u8 id,
767 const struct wpabuf *reqData,
768 struct eap_sim_attrs *attr)
769 {
770 int id_error;
771 struct wpabuf *buf;
772
773 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
774
775 id_error = 0;
776 switch (attr->id_req) {
777 case NO_ID_REQ:
778 break;
779 case ANY_ID:
780 if (data->num_id_req > 0)
781 id_error++;
782 data->num_id_req++;
783 break;
784 case FULLAUTH_ID:
785 if (data->num_id_req > 1)
786 id_error++;
787 data->num_id_req++;
788 break;
789 case PERMANENT_ID:
790 if (data->num_id_req > 2)
791 id_error++;
792 data->num_id_req++;
793 break;
794 }
795 if (id_error) {
796 wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
797 "used within one authentication");
798 return eap_aka_client_error(data, id,
799 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
800 }
801
802 buf = eap_aka_response_identity(sm, data, id, attr->id_req);
803
804 if (data->prev_id != id) {
805 eap_aka_add_id_msg(data, reqData);
806 eap_aka_add_id_msg(data, buf);
807 data->prev_id = id;
808 }
809
810 return buf;
811 }
812
813
eap_aka_verify_mac(struct eap_aka_data * data,const struct wpabuf * req,const u8 * mac,const u8 * extra,size_t extra_len)814 static int eap_aka_verify_mac(struct eap_aka_data *data,
815 const struct wpabuf *req,
816 const u8 *mac, const u8 *extra,
817 size_t extra_len)
818 {
819 if (data->eap_method == EAP_TYPE_AKA_PRIME)
820 return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
821 extra_len);
822 return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
823 }
824
825
826 #ifdef EAP_AKA_PRIME
eap_aka_prime_kdf_select(struct eap_aka_data * data,u8 id,u16 kdf)827 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
828 u8 id, u16 kdf)
829 {
830 struct eap_sim_msg *msg;
831
832 data->kdf_negotiation = 1;
833 data->kdf = kdf;
834 wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
835 "select)", id);
836 msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
837 EAP_AKA_SUBTYPE_CHALLENGE);
838 wpa_printf(MSG_DEBUG, " AT_KDF");
839 eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
840 return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
841 }
842
843
eap_aka_prime_kdf_neg(struct eap_aka_data * data,u8 id,struct eap_sim_attrs * attr)844 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
845 u8 id, struct eap_sim_attrs *attr)
846 {
847 size_t i;
848
849 for (i = 0; i < attr->kdf_count; i++) {
850 if (attr->kdf[i] == EAP_AKA_PRIME_KDF) {
851 os_memcpy(data->last_kdf_attrs, attr->kdf,
852 sizeof(u16) * attr->kdf_count);
853 data->last_kdf_count = attr->kdf_count;
854 return eap_aka_prime_kdf_select(data, id,
855 EAP_AKA_PRIME_KDF);
856 }
857 }
858
859 /* No matching KDF found - fail authentication as if AUTN had been
860 * incorrect */
861 return eap_aka_authentication_reject(data, id);
862 }
863
864
eap_aka_prime_kdf_valid(struct eap_aka_data * data,struct eap_sim_attrs * attr)865 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
866 struct eap_sim_attrs *attr)
867 {
868 size_t i, j;
869
870 if (attr->kdf_count == 0)
871 return 0;
872
873 /* The only allowed (and required) duplication of a KDF is the addition
874 * of the selected KDF into the beginning of the list. */
875
876 if (data->kdf_negotiation) {
877 /* When the peer receives the new EAP-Request/AKA'-Challenge
878 * message, must check only requested change occurred in the
879 * list of AT_KDF attributes. If there are any other changes,
880 * the peer must behave like the case that AT_MAC had been
881 * incorrect and authentication is failed. These are defined in
882 * EAP-AKA' specification RFC 5448, Section 3.2. */
883 if (attr->kdf[0] != data->kdf) {
884 wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
885 "accept the selected KDF");
886 return -1;
887 }
888
889 if (attr->kdf_count > EAP_AKA_PRIME_KDF_MAX ||
890 attr->kdf_count != data->last_kdf_count + 1) {
891 wpa_printf(MSG_WARNING,
892 "EAP-AKA': The length of KDF attributes is wrong");
893 return -1;
894 }
895
896 for (i = 1; i < attr->kdf_count; i++) {
897 if (attr->kdf[i] != data->last_kdf_attrs[i - 1]) {
898 wpa_printf(MSG_WARNING,
899 "EAP-AKA': The KDF attributes except selected KDF are not same as original one");
900 return -1;
901 }
902 }
903 }
904
905 for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
906 for (j = i + 1; j < attr->kdf_count; j++) {
907 if (attr->kdf[i] == attr->kdf[j]) {
908 wpa_printf(MSG_WARNING, "EAP-AKA': The server "
909 "included a duplicated KDF");
910 return 0;
911 }
912 }
913 }
914
915 return 1;
916 }
917 #endif /* EAP_AKA_PRIME */
918
919
eap_aka_process_challenge(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)920 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
921 struct eap_aka_data *data,
922 u8 id,
923 const struct wpabuf *reqData,
924 struct eap_sim_attrs *attr)
925 {
926 const u8 *identity;
927 size_t identity_len;
928 int res;
929 struct eap_sim_attrs eattr;
930
931 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
932
933 if (attr->checkcode &&
934 eap_aka_verify_checkcode(data, attr->checkcode,
935 attr->checkcode_len)) {
936 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
937 "message");
938 return eap_aka_client_error(data, id,
939 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
940 }
941
942 #ifdef EAP_AKA_PRIME
943 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
944 if (!attr->kdf_input || attr->kdf_input_len == 0) {
945 wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
946 "did not include non-empty AT_KDF_INPUT");
947 /* Fail authentication as if AUTN had been incorrect */
948 return eap_aka_authentication_reject(data, id);
949 }
950 os_free(data->network_name);
951 data->network_name = os_memdup(attr->kdf_input,
952 attr->kdf_input_len);
953 if (data->network_name == NULL) {
954 wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
955 "storing Network Name");
956 return eap_aka_authentication_reject(data, id);
957 }
958 data->network_name_len = attr->kdf_input_len;
959 wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
960 "(AT_KDF_INPUT)",
961 data->network_name, data->network_name_len);
962 /* TODO: check Network Name per 3GPP.33.402 */
963
964 res = eap_aka_prime_kdf_valid(data, attr);
965 if (res == 0)
966 return eap_aka_authentication_reject(data, id);
967 else if (res == -1)
968 return eap_aka_client_error(
969 data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
970
971 if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
972 return eap_aka_prime_kdf_neg(data, id, attr);
973
974 data->kdf = EAP_AKA_PRIME_KDF;
975 wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
976 }
977
978 if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
979 u16 flags = WPA_GET_BE16(attr->bidding);
980 if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
981 eap_allowed_method(sm, EAP_VENDOR_IETF,
982 EAP_TYPE_AKA_PRIME)) {
983 wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
984 "AKA' to AKA detected");
985 /* Fail authentication as if AUTN had been incorrect */
986 return eap_aka_authentication_reject(data, id);
987 }
988 }
989 #endif /* EAP_AKA_PRIME */
990
991 data->reauth = 0;
992 if (!attr->mac || !attr->rand || !attr->autn) {
993 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
994 "did not include%s%s%s",
995 !attr->mac ? " AT_MAC" : "",
996 !attr->rand ? " AT_RAND" : "",
997 !attr->autn ? " AT_AUTN" : "");
998 return eap_aka_client_error(data, id,
999 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1000 }
1001 os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
1002 os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
1003
1004 res = eap_aka_umts_auth(sm, data);
1005 if (res == -1) {
1006 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
1007 "failed (AUTN)");
1008 return eap_aka_authentication_reject(data, id);
1009 } else if (res == -2) {
1010 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
1011 "failed (AUTN seq# -> AUTS)");
1012 return eap_aka_synchronization_failure(data, id, attr);
1013 } else if (res > 0) {
1014 wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
1015 return NULL;
1016 } else if (res) {
1017 wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
1018 return eap_aka_client_error(data, id,
1019 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1020 }
1021 #ifdef EAP_AKA_PRIME
1022 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1023 /* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
1024 * needed 6-octet SQN ^ AK for CK',IK' derivation */
1025 u16 amf = WPA_GET_BE16(data->autn + 6);
1026 if (!(amf & 0x8000)) {
1027 wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
1028 "not set (AMF=0x%4x)", amf);
1029 return eap_aka_authentication_reject(data, id);
1030 }
1031 eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
1032 data->autn,
1033 data->network_name,
1034 data->network_name_len);
1035 }
1036 #endif /* EAP_AKA_PRIME */
1037 if (data->last_eap_identity) {
1038 identity = data->last_eap_identity;
1039 identity_len = data->last_eap_identity_len;
1040 } else if (data->pseudonym && !data->anonymous_flag) {
1041 identity = data->pseudonym;
1042 identity_len = data->pseudonym_len;
1043 } else {
1044 struct eap_peer_config *config;
1045
1046 config = eap_get_config(sm);
1047 if (config && config->imsi_identity) {
1048 identity = config->imsi_identity;
1049 identity_len = config->imsi_identity_len;
1050 } else {
1051 identity = eap_get_config_identity(sm, &identity_len);
1052 }
1053 }
1054 wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
1055 "derivation", identity, identity_len);
1056 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1057 eap_aka_prime_derive_keys(identity, identity_len, data->ik,
1058 data->ck, data->k_encr, data->k_aut,
1059 data->k_re, data->msk, data->emsk);
1060 } else {
1061 eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
1062 data->mk);
1063 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
1064 data->msk, data->emsk);
1065 }
1066 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1067 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
1068 "used invalid AT_MAC");
1069 return eap_aka_client_error(data, id,
1070 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1071 }
1072
1073 /* Old reauthentication identity must not be used anymore. In
1074 * other words, if no new identities are received, full
1075 * authentication will be used on next reauthentication (using
1076 * pseudonym identity or permanent identity). */
1077 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1078
1079 if (attr->encr_data) {
1080 u8 *decrypted;
1081 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1082 attr->encr_data_len, attr->iv,
1083 &eattr, 0);
1084 if (decrypted == NULL) {
1085 return eap_aka_client_error(
1086 data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1087 }
1088 eap_aka_learn_ids(sm, data, &eattr);
1089 os_free(decrypted);
1090 }
1091
1092 if (data->result_ind && attr->result_ind)
1093 data->use_result_ind = 1;
1094
1095 if (data->state != FAILURE) {
1096 eap_aka_state(data, data->use_result_ind ?
1097 RESULT_SUCCESS : SUCCESS);
1098 }
1099
1100 data->num_id_req = 0;
1101 data->num_notification = 0;
1102 /* RFC 4187 specifies that counter is initialized to one after
1103 * fullauth, but initializing it to zero makes it easier to implement
1104 * reauth verification. */
1105 data->counter = 0;
1106 return eap_aka_response_challenge(data, id);
1107 }
1108
1109
eap_aka_process_notification_reauth(struct eap_aka_data * data,struct eap_sim_attrs * attr)1110 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
1111 struct eap_sim_attrs *attr)
1112 {
1113 struct eap_sim_attrs eattr;
1114 u8 *decrypted;
1115
1116 if (attr->encr_data == NULL || attr->iv == NULL) {
1117 wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
1118 "reauth did not include encrypted data");
1119 return -1;
1120 }
1121
1122 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1123 attr->encr_data_len, attr->iv, &eattr,
1124 0);
1125 if (decrypted == NULL) {
1126 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1127 "data from notification message");
1128 return -1;
1129 }
1130
1131 if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
1132 wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
1133 "message does not match with counter in reauth "
1134 "message");
1135 os_free(decrypted);
1136 return -1;
1137 }
1138
1139 os_free(decrypted);
1140 return 0;
1141 }
1142
1143
eap_aka_process_notification_auth(struct eap_aka_data * data,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1144 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
1145 const struct wpabuf *reqData,
1146 struct eap_sim_attrs *attr)
1147 {
1148 if (attr->mac == NULL) {
1149 wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
1150 "Notification message");
1151 return -1;
1152 }
1153
1154 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1155 wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
1156 "used invalid AT_MAC");
1157 return -1;
1158 }
1159
1160 if (data->reauth &&
1161 eap_aka_process_notification_reauth(data, attr)) {
1162 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
1163 "message after reauth");
1164 return -1;
1165 }
1166
1167 return 0;
1168 }
1169
1170
eap_aka_process_notification(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1171 static struct wpabuf * eap_aka_process_notification(
1172 struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1173 const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1174 {
1175 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
1176 if (data->num_notification > 0) {
1177 wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
1178 "rounds (only one allowed)");
1179 return eap_aka_client_error(data, id,
1180 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1181 }
1182 data->num_notification++;
1183 if (attr->notification == -1) {
1184 wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
1185 "Notification message");
1186 return eap_aka_client_error(data, id,
1187 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1188 }
1189
1190 if ((attr->notification & 0x4000) == 0 &&
1191 eap_aka_process_notification_auth(data, reqData, attr)) {
1192 return eap_aka_client_error(data, id,
1193 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1194 }
1195
1196 eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
1197 if (attr->notification >= 0 && attr->notification < 32768) {
1198 data->error_code = attr->notification;
1199 eap_aka_state(data, FAILURE);
1200 } else if (attr->notification == EAP_SIM_SUCCESS &&
1201 data->state == RESULT_SUCCESS)
1202 eap_aka_state(data, SUCCESS);
1203 return eap_aka_response_notification(data, id, attr->notification);
1204 }
1205
1206
eap_aka_process_reauthentication(struct eap_sm * sm,struct eap_aka_data * data,u8 id,const struct wpabuf * reqData,struct eap_sim_attrs * attr)1207 static struct wpabuf * eap_aka_process_reauthentication(
1208 struct eap_sm *sm, struct eap_aka_data *data, u8 id,
1209 const struct wpabuf *reqData, struct eap_sim_attrs *attr)
1210 {
1211 struct eap_sim_attrs eattr;
1212 u8 *decrypted;
1213
1214 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
1215
1216 if (attr->checkcode &&
1217 eap_aka_verify_checkcode(data, attr->checkcode,
1218 attr->checkcode_len)) {
1219 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
1220 "message");
1221 return eap_aka_client_error(data, id,
1222 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1223 }
1224
1225 if (data->reauth_id == NULL) {
1226 wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
1227 "reauthentication, but no reauth_id available");
1228 return eap_aka_client_error(data, id,
1229 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1230 }
1231
1232 data->reauth = 1;
1233 if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
1234 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1235 "did not have valid AT_MAC");
1236 return eap_aka_client_error(data, id,
1237 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1238 }
1239
1240 if (attr->encr_data == NULL || attr->iv == NULL) {
1241 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1242 "message did not include encrypted data");
1243 return eap_aka_client_error(data, id,
1244 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1245 }
1246
1247 decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1248 attr->encr_data_len, attr->iv, &eattr,
1249 0);
1250 if (decrypted == NULL) {
1251 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1252 "data from reauthentication message");
1253 return eap_aka_client_error(data, id,
1254 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1255 }
1256
1257 if (eattr.nonce_s == NULL || eattr.counter < 0) {
1258 wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
1259 !eattr.nonce_s ? " AT_NONCE_S" : "",
1260 eattr.counter < 0 ? " AT_COUNTER" : "");
1261 os_free(decrypted);
1262 return eap_aka_client_error(data, id,
1263 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1264 }
1265
1266 if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
1267 struct wpabuf *res;
1268 wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
1269 "(%d <= %d)", eattr.counter, data->counter);
1270 data->counter_too_small = eattr.counter;
1271
1272 /* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
1273 * reauth_id must not be used to start a new reauthentication.
1274 * However, since it was used in the last EAP-Response-Identity
1275 * packet, it has to saved for the following fullauth to be
1276 * used in MK derivation. */
1277 os_free(data->last_eap_identity);
1278 data->last_eap_identity = data->reauth_id;
1279 data->last_eap_identity_len = data->reauth_id_len;
1280 data->reauth_id = NULL;
1281 data->reauth_id_len = 0;
1282
1283 res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
1284 os_free(decrypted);
1285
1286 return res;
1287 }
1288 data->counter = eattr.counter;
1289
1290 os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
1291 wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
1292 data->nonce_s, EAP_SIM_NONCE_S_LEN);
1293
1294 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1295 eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
1296 data->reauth_id,
1297 data->reauth_id_len,
1298 data->nonce_s,
1299 data->msk, data->emsk);
1300 } else {
1301 eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
1302 data->reauth_id_len,
1303 data->nonce_s, data->mk,
1304 data->msk, data->emsk);
1305 }
1306 eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1307 eap_aka_learn_ids(sm, data, &eattr);
1308
1309 if (data->result_ind && attr->result_ind)
1310 data->use_result_ind = 1;
1311
1312 if (data->state != FAILURE) {
1313 eap_aka_state(data, data->use_result_ind ?
1314 RESULT_SUCCESS : SUCCESS);
1315 }
1316
1317 data->num_id_req = 0;
1318 data->num_notification = 0;
1319 if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
1320 wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
1321 "fast reauths performed - force fullauth");
1322 eap_aka_clear_identities(sm, data,
1323 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
1324 }
1325 os_free(decrypted);
1326 return eap_aka_response_reauth(data, id, 0, data->nonce_s);
1327 }
1328
1329
eap_aka_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)1330 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
1331 struct eap_method_ret *ret,
1332 const struct wpabuf *reqData)
1333 {
1334 struct eap_aka_data *data = priv;
1335 const struct eap_hdr *req;
1336 u8 subtype, id;
1337 struct wpabuf *res;
1338 const u8 *pos;
1339 struct eap_sim_attrs attr;
1340 size_t len;
1341
1342 wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
1343 if (eap_get_config_identity(sm, &len) == NULL) {
1344 wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
1345 eap_sm_request_identity(sm);
1346 ret->ignore = TRUE;
1347 return NULL;
1348 }
1349
1350 pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
1351 &len);
1352 if (pos == NULL || len < 3) {
1353 ret->ignore = TRUE;
1354 return NULL;
1355 }
1356 req = wpabuf_head(reqData);
1357 id = req->identifier;
1358 len = be_to_host16(req->length);
1359
1360 ret->ignore = FALSE;
1361 ret->methodState = METHOD_MAY_CONT;
1362 ret->decision = DECISION_FAIL;
1363 ret->allowNotifications = TRUE;
1364
1365 subtype = *pos++;
1366 wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
1367 pos += 2; /* Reserved */
1368
1369 if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
1370 data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1371 0)) {
1372 res = eap_aka_client_error(data, id,
1373 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1374 goto done;
1375 }
1376
1377 switch (subtype) {
1378 case EAP_AKA_SUBTYPE_IDENTITY:
1379 res = eap_aka_process_identity(sm, data, id, reqData, &attr);
1380 break;
1381 case EAP_AKA_SUBTYPE_CHALLENGE:
1382 res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
1383 break;
1384 case EAP_AKA_SUBTYPE_NOTIFICATION:
1385 res = eap_aka_process_notification(sm, data, id, reqData,
1386 &attr);
1387 break;
1388 case EAP_AKA_SUBTYPE_REAUTHENTICATION:
1389 res = eap_aka_process_reauthentication(sm, data, id, reqData,
1390 &attr);
1391 break;
1392 case EAP_AKA_SUBTYPE_CLIENT_ERROR:
1393 wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
1394 res = eap_aka_client_error(data, id,
1395 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1396 break;
1397 default:
1398 wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
1399 res = eap_aka_client_error(data, id,
1400 EAP_AKA_UNABLE_TO_PROCESS_PACKET);
1401 break;
1402 }
1403
1404 done:
1405 if (data->state == FAILURE) {
1406 ret->decision = DECISION_FAIL;
1407 ret->methodState = METHOD_DONE;
1408 } else if (data->state == SUCCESS) {
1409 ret->decision = data->use_result_ind ?
1410 DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
1411 /*
1412 * It is possible for the server to reply with AKA
1413 * Notification, so we must allow the method to continue and
1414 * not only accept EAP-Success at this point.
1415 */
1416 ret->methodState = data->use_result_ind ?
1417 METHOD_DONE : METHOD_MAY_CONT;
1418 } else if (data->state == RESULT_SUCCESS)
1419 ret->methodState = METHOD_CONT;
1420
1421 if (ret->methodState == METHOD_DONE) {
1422 ret->allowNotifications = FALSE;
1423 }
1424
1425 return res;
1426 }
1427
1428
eap_aka_has_reauth_data(struct eap_sm * sm,void * priv)1429 static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
1430 {
1431 struct eap_aka_data *data = priv;
1432 return data->pseudonym || data->reauth_id;
1433 }
1434
1435
eap_aka_deinit_for_reauth(struct eap_sm * sm,void * priv)1436 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
1437 {
1438 struct eap_aka_data *data = priv;
1439 eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
1440 data->prev_id = -1;
1441 wpabuf_free(data->id_msgs);
1442 data->id_msgs = NULL;
1443 data->use_result_ind = 0;
1444 data->kdf_negotiation = 0;
1445 eap_aka_clear_keys(data, 1);
1446 }
1447
1448
eap_aka_init_for_reauth(struct eap_sm * sm,void * priv)1449 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
1450 {
1451 struct eap_aka_data *data = priv;
1452 data->num_id_req = 0;
1453 data->num_notification = 0;
1454 eap_aka_state(data, CONTINUE);
1455 return priv;
1456 }
1457
1458
eap_aka_get_identity(struct eap_sm * sm,void * priv,size_t * len)1459 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
1460 size_t *len)
1461 {
1462 struct eap_aka_data *data = priv;
1463
1464 if (data->reauth_id) {
1465 *len = data->reauth_id_len;
1466 return data->reauth_id;
1467 }
1468
1469 if (data->pseudonym) {
1470 *len = data->pseudonym_len;
1471 return data->pseudonym;
1472 }
1473
1474 return NULL;
1475 }
1476
1477
eap_aka_isKeyAvailable(struct eap_sm * sm,void * priv)1478 static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
1479 {
1480 struct eap_aka_data *data = priv;
1481 return data->state == SUCCESS;
1482 }
1483
1484
eap_aka_getKey(struct eap_sm * sm,void * priv,size_t * len)1485 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1486 {
1487 struct eap_aka_data *data = priv;
1488 u8 *key;
1489
1490 if (data->state != SUCCESS)
1491 return NULL;
1492
1493 key = os_memdup(data->msk, EAP_SIM_KEYING_DATA_LEN);
1494 if (key == NULL)
1495 return NULL;
1496
1497 *len = EAP_SIM_KEYING_DATA_LEN;
1498
1499 return key;
1500 }
1501
1502
eap_aka_get_session_id(struct eap_sm * sm,void * priv,size_t * len)1503 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1504 {
1505 struct eap_aka_data *data = priv;
1506 u8 *id;
1507
1508 if (data->state != SUCCESS)
1509 return NULL;
1510
1511 *len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1512 id = os_malloc(*len);
1513 if (id == NULL)
1514 return NULL;
1515
1516 id[0] = data->eap_method;
1517 os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1518 os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn, EAP_AKA_AUTN_LEN);
1519 wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1520
1521 return id;
1522 }
1523
1524
eap_aka_get_emsk(struct eap_sm * sm,void * priv,size_t * len)1525 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1526 {
1527 struct eap_aka_data *data = priv;
1528 u8 *key;
1529
1530 if (data->state != SUCCESS)
1531 return NULL;
1532
1533 key = os_memdup(data->emsk, EAP_EMSK_LEN);
1534 if (key == NULL)
1535 return NULL;
1536
1537 *len = EAP_EMSK_LEN;
1538
1539 return key;
1540 }
1541
1542
eap_aka_get_error_code(void * priv)1543 static int eap_aka_get_error_code(void *priv)
1544 {
1545 struct eap_aka_data *data = priv;
1546 int current_data_error;
1547
1548 if (!data)
1549 return NO_EAP_METHOD_ERROR;
1550
1551 current_data_error = data->error_code;
1552
1553 /* Now reset for next transaction */
1554 data->error_code = NO_EAP_METHOD_ERROR;
1555
1556 return current_data_error;
1557 }
1558
1559
eap_peer_aka_register(void)1560 int eap_peer_aka_register(void)
1561 {
1562 struct eap_method *eap;
1563
1564 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1565 EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1566 if (eap == NULL)
1567 return -1;
1568
1569 eap->init = eap_aka_init;
1570 eap->deinit = eap_aka_deinit;
1571 eap->process = eap_aka_process;
1572 eap->isKeyAvailable = eap_aka_isKeyAvailable;
1573 eap->getKey = eap_aka_getKey;
1574 eap->getSessionId = eap_aka_get_session_id;
1575 eap->has_reauth_data = eap_aka_has_reauth_data;
1576 eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1577 eap->init_for_reauth = eap_aka_init_for_reauth;
1578 eap->get_identity = eap_aka_get_identity;
1579 eap->get_emsk = eap_aka_get_emsk;
1580 eap->get_error_code = eap_aka_get_error_code;
1581
1582 return eap_peer_method_register(eap);
1583 }
1584
1585
1586 #ifdef EAP_AKA_PRIME
eap_peer_aka_prime_register(void)1587 int eap_peer_aka_prime_register(void)
1588 {
1589 struct eap_method *eap;
1590
1591 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1592 EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1593 "AKA'");
1594 if (eap == NULL)
1595 return -1;
1596
1597 eap->init = eap_aka_prime_init;
1598 eap->deinit = eap_aka_deinit;
1599 eap->process = eap_aka_process;
1600 eap->isKeyAvailable = eap_aka_isKeyAvailable;
1601 eap->getKey = eap_aka_getKey;
1602 eap->getSessionId = eap_aka_get_session_id;
1603 eap->has_reauth_data = eap_aka_has_reauth_data;
1604 eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
1605 eap->init_for_reauth = eap_aka_init_for_reauth;
1606 eap->get_identity = eap_aka_get_identity;
1607 eap->get_emsk = eap_aka_get_emsk;
1608 eap->get_error_code = eap_aka_get_error_code;
1609
1610 return eap_peer_method_register(eap);
1611 }
1612 #endif /* EAP_AKA_PRIME */
1613