xref: /netbsd-src/external/bsd/wpa/dist/src/eap_common/eap_sim_common.c (revision 4d12bfcd155352508213ace5ccc59ce930ea2974)
1 /*
2  * EAP peer/server: EAP-SIM/AKA/AKA' shared routines
3  * Copyright (c) 2004-2008, Jouni Malinen <j@w1.fi>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * Alternatively, this software may be distributed under the terms of BSD
10  * license.
11  *
12  * See README and COPYING for more details.
13  */
14 
15 #include "includes.h"
16 
17 #include "common.h"
18 #include "wpabuf.h"
19 #include "crypto/aes_wrap.h"
20 #include "crypto/crypto.h"
21 #include "crypto/sha1.h"
22 #include "crypto/sha256.h"
23 #include "crypto/random.h"
24 #include "eap_common/eap_defs.h"
25 #include "eap_common/eap_sim_common.h"
26 
27 
28 static int eap_sim_prf(const u8 *key, u8 *x, size_t xlen)
29 {
30 	return fips186_2_prf(key, EAP_SIM_MK_LEN, x, xlen);
31 }
32 
33 
34 void eap_sim_derive_mk(const u8 *identity, size_t identity_len,
35 		       const u8 *nonce_mt, u16 selected_version,
36 		       const u8 *ver_list, size_t ver_list_len,
37 		       int num_chal, const u8 *kc, u8 *mk)
38 {
39 	u8 sel_ver[2];
40 	const unsigned char *addr[5];
41 	size_t len[5];
42 
43 	addr[0] = identity;
44 	len[0] = identity_len;
45 	addr[1] = kc;
46 	len[1] = num_chal * EAP_SIM_KC_LEN;
47 	addr[2] = nonce_mt;
48 	len[2] = EAP_SIM_NONCE_MT_LEN;
49 	addr[3] = ver_list;
50 	len[3] = ver_list_len;
51 	addr[4] = sel_ver;
52 	len[4] = 2;
53 
54 	WPA_PUT_BE16(sel_ver, selected_version);
55 
56 	/* MK = SHA1(Identity|n*Kc|NONCE_MT|Version List|Selected Version) */
57 	sha1_vector(5, addr, len, mk);
58 	wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: MK", mk, EAP_SIM_MK_LEN);
59 }
60 
61 
62 void eap_aka_derive_mk(const u8 *identity, size_t identity_len,
63 		       const u8 *ik, const u8 *ck, u8 *mk)
64 {
65 	const u8 *addr[3];
66 	size_t len[3];
67 
68 	addr[0] = identity;
69 	len[0] = identity_len;
70 	addr[1] = ik;
71 	len[1] = EAP_AKA_IK_LEN;
72 	addr[2] = ck;
73 	len[2] = EAP_AKA_CK_LEN;
74 
75 	/* MK = SHA1(Identity|IK|CK) */
76 	sha1_vector(3, addr, len, mk);
77 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", ik, EAP_AKA_IK_LEN);
78 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", ck, EAP_AKA_CK_LEN);
79 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: MK", mk, EAP_SIM_MK_LEN);
80 }
81 
82 
83 int eap_sim_derive_keys(const u8 *mk, u8 *k_encr, u8 *k_aut, u8 *msk, u8 *emsk)
84 {
85 	u8 buf[EAP_SIM_K_ENCR_LEN + EAP_SIM_K_AUT_LEN +
86 	       EAP_SIM_KEYING_DATA_LEN + EAP_EMSK_LEN], *pos;
87 	if (eap_sim_prf(mk, buf, sizeof(buf)) < 0) {
88 		wpa_printf(MSG_ERROR, "EAP-SIM: Failed to derive keys");
89 		return -1;
90 	}
91 	pos = buf;
92 	os_memcpy(k_encr, pos, EAP_SIM_K_ENCR_LEN);
93 	pos += EAP_SIM_K_ENCR_LEN;
94 	os_memcpy(k_aut, pos, EAP_SIM_K_AUT_LEN);
95 	pos += EAP_SIM_K_AUT_LEN;
96 	os_memcpy(msk, pos, EAP_SIM_KEYING_DATA_LEN);
97 	pos += EAP_SIM_KEYING_DATA_LEN;
98 	os_memcpy(emsk, pos, EAP_EMSK_LEN);
99 
100 	wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: K_encr",
101 			k_encr, EAP_SIM_K_ENCR_LEN);
102 	wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: K_aut",
103 			k_aut, EAP_SIM_K_AUT_LEN);
104 	wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: keying material (MSK)",
105 			msk, EAP_SIM_KEYING_DATA_LEN);
106 	wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: EMSK", emsk, EAP_EMSK_LEN);
107 	os_memset(buf, 0, sizeof(buf));
108 
109 	return 0;
110 }
111 
112 
113 int eap_sim_derive_keys_reauth(u16 _counter,
114 			       const u8 *identity, size_t identity_len,
115 			       const u8 *nonce_s, const u8 *mk, u8 *msk,
116 			       u8 *emsk)
117 {
118 	u8 xkey[SHA1_MAC_LEN];
119 	u8 buf[EAP_SIM_KEYING_DATA_LEN + EAP_EMSK_LEN + 32];
120 	u8 counter[2];
121 	const u8 *addr[4];
122 	size_t len[4];
123 
124 	while (identity_len > 0 && identity[identity_len - 1] == 0) {
125 		wpa_printf(MSG_DEBUG, "EAP-SIM: Workaround - drop null "
126 			   "character from the end of identity");
127 		identity_len--;
128 	}
129 	addr[0] = identity;
130 	len[0] = identity_len;
131 	addr[1] = counter;
132 	len[1] = 2;
133 	addr[2] = nonce_s;
134 	len[2] = EAP_SIM_NONCE_S_LEN;
135 	addr[3] = mk;
136 	len[3] = EAP_SIM_MK_LEN;
137 
138 	WPA_PUT_BE16(counter, _counter);
139 
140 	wpa_printf(MSG_DEBUG, "EAP-SIM: Deriving keying data from reauth");
141 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Identity",
142 			  identity, identity_len);
143 	wpa_hexdump(MSG_DEBUG, "EAP-SIM: counter", counter, 2);
144 	wpa_hexdump(MSG_DEBUG, "EAP-SIM: NONCE_S", nonce_s,
145 		    EAP_SIM_NONCE_S_LEN);
146 	wpa_hexdump_key(MSG_DEBUG, "EAP-SIM: MK", mk, EAP_SIM_MK_LEN);
147 
148 	/* XKEY' = SHA1(Identity|counter|NONCE_S|MK) */
149 	sha1_vector(4, addr, len, xkey);
150 	wpa_hexdump(MSG_DEBUG, "EAP-SIM: XKEY'", xkey, SHA1_MAC_LEN);
151 
152 	if (eap_sim_prf(xkey, buf, sizeof(buf)) < 0) {
153 		wpa_printf(MSG_ERROR, "EAP-SIM: Failed to derive keys");
154 		return -1;
155 	}
156 	if (msk) {
157 		os_memcpy(msk, buf, EAP_SIM_KEYING_DATA_LEN);
158 		wpa_hexdump(MSG_DEBUG, "EAP-SIM: keying material (MSK)",
159 			    msk, EAP_SIM_KEYING_DATA_LEN);
160 	}
161 	if (emsk) {
162 		os_memcpy(emsk, buf + EAP_SIM_KEYING_DATA_LEN, EAP_EMSK_LEN);
163 		wpa_hexdump(MSG_DEBUG, "EAP-SIM: EMSK", emsk, EAP_EMSK_LEN);
164 	}
165 	os_memset(buf, 0, sizeof(buf));
166 
167 	return 0;
168 }
169 
170 
171 int eap_sim_verify_mac(const u8 *k_aut, const struct wpabuf *req,
172 		       const u8 *mac, const u8 *extra, size_t extra_len)
173 {
174 	unsigned char hmac[SHA1_MAC_LEN];
175 	const u8 *addr[2];
176 	size_t len[2];
177 	u8 *tmp;
178 
179 	if (mac == NULL || wpabuf_len(req) < EAP_SIM_MAC_LEN ||
180 	    mac < wpabuf_head_u8(req) ||
181 	    mac > wpabuf_head_u8(req) + wpabuf_len(req) - EAP_SIM_MAC_LEN)
182 		return -1;
183 
184 	tmp = os_malloc(wpabuf_len(req));
185 	if (tmp == NULL)
186 		return -1;
187 
188 	addr[0] = tmp;
189 	len[0] = wpabuf_len(req);
190 	addr[1] = extra;
191 	len[1] = extra_len;
192 
193 	/* HMAC-SHA1-128 */
194 	os_memcpy(tmp, wpabuf_head(req), wpabuf_len(req));
195 	os_memset(tmp + (mac - wpabuf_head_u8(req)), 0, EAP_SIM_MAC_LEN);
196 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Verify MAC - msg",
197 		    tmp, wpabuf_len(req));
198 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Verify MAC - extra data",
199 		    extra, extra_len);
200 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: Verify MAC - K_aut",
201 			k_aut, EAP_SIM_K_AUT_LEN);
202 	hmac_sha1_vector(k_aut, EAP_SIM_K_AUT_LEN, 2, addr, len, hmac);
203 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Verify MAC: MAC",
204 		    hmac, EAP_SIM_MAC_LEN);
205 	os_free(tmp);
206 
207 	return (os_memcmp(hmac, mac, EAP_SIM_MAC_LEN) == 0) ? 0 : 1;
208 }
209 
210 
211 void eap_sim_add_mac(const u8 *k_aut, const u8 *msg, size_t msg_len, u8 *mac,
212 		     const u8 *extra, size_t extra_len)
213 {
214 	unsigned char hmac[SHA1_MAC_LEN];
215 	const u8 *addr[2];
216 	size_t len[2];
217 
218 	addr[0] = msg;
219 	len[0] = msg_len;
220 	addr[1] = extra;
221 	len[1] = extra_len;
222 
223 	/* HMAC-SHA1-128 */
224 	os_memset(mac, 0, EAP_SIM_MAC_LEN);
225 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Add MAC - msg", msg, msg_len);
226 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Add MAC - extra data",
227 		    extra, extra_len);
228 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-SIM: Add MAC - K_aut",
229 			k_aut, EAP_SIM_K_AUT_LEN);
230 	hmac_sha1_vector(k_aut, EAP_SIM_K_AUT_LEN, 2, addr, len, hmac);
231 	os_memcpy(mac, hmac, EAP_SIM_MAC_LEN);
232 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Add MAC: MAC",
233 		    mac, EAP_SIM_MAC_LEN);
234 }
235 
236 
237 #if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
238 static void prf_prime(const u8 *k, const char *seed1,
239 		      const u8 *seed2, size_t seed2_len,
240 		      const u8 *seed3, size_t seed3_len,
241 		      u8 *res, size_t res_len)
242 {
243 	const u8 *addr[5];
244 	size_t len[5];
245 	u8 hash[SHA256_MAC_LEN];
246 	u8 iter;
247 
248 	/*
249 	 * PRF'(K,S) = T1 | T2 | T3 | T4 | ...
250 	 * T1 = HMAC-SHA-256 (K, S | 0x01)
251 	 * T2 = HMAC-SHA-256 (K, T1 | S | 0x02)
252 	 * T3 = HMAC-SHA-256 (K, T2 | S | 0x03)
253 	 * T4 = HMAC-SHA-256 (K, T3 | S | 0x04)
254 	 * ...
255 	 */
256 
257 	addr[0] = hash;
258 	len[0] = 0;
259 	addr[1] = (const u8 *) seed1;
260 	len[1] = os_strlen(seed1);
261 	addr[2] = seed2;
262 	len[2] = seed2_len;
263 	addr[3] = seed3;
264 	len[3] = seed3_len;
265 	addr[4] = &iter;
266 	len[4] = 1;
267 
268 	iter = 0;
269 	while (res_len) {
270 		size_t hlen;
271 		iter++;
272 		hmac_sha256_vector(k, 32, 5, addr, len, hash);
273 		len[0] = SHA256_MAC_LEN;
274 		hlen = res_len > SHA256_MAC_LEN ? SHA256_MAC_LEN : res_len;
275 		os_memcpy(res, hash, hlen);
276 		res += hlen;
277 		res_len -= hlen;
278 	}
279 }
280 
281 
282 void eap_aka_prime_derive_keys(const u8 *identity, size_t identity_len,
283 			       const u8 *ik, const u8 *ck, u8 *k_encr,
284 			       u8 *k_aut, u8 *k_re, u8 *msk, u8 *emsk)
285 {
286 	u8 key[EAP_AKA_IK_LEN + EAP_AKA_CK_LEN];
287 	u8 keys[EAP_SIM_K_ENCR_LEN + EAP_AKA_PRIME_K_AUT_LEN +
288 		EAP_AKA_PRIME_K_RE_LEN + EAP_MSK_LEN + EAP_EMSK_LEN];
289 	u8 *pos;
290 
291 	/*
292 	 * MK = PRF'(IK'|CK',"EAP-AKA'"|Identity)
293 	 * K_encr = MK[0..127]
294 	 * K_aut  = MK[128..383]
295 	 * K_re   = MK[384..639]
296 	 * MSK    = MK[640..1151]
297 	 * EMSK   = MK[1152..1663]
298 	 */
299 
300 	os_memcpy(key, ik, EAP_AKA_IK_LEN);
301 	os_memcpy(key + EAP_AKA_IK_LEN, ck, EAP_AKA_CK_LEN);
302 
303 	prf_prime(key, "EAP-AKA'", identity, identity_len, NULL, 0,
304 		  keys, sizeof(keys));
305 
306 	pos = keys;
307 	os_memcpy(k_encr, pos, EAP_SIM_K_ENCR_LEN);
308 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': K_encr",
309 			k_encr, EAP_SIM_K_ENCR_LEN);
310 	pos += EAP_SIM_K_ENCR_LEN;
311 
312 	os_memcpy(k_aut, pos, EAP_AKA_PRIME_K_AUT_LEN);
313 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': K_aut",
314 			k_aut, EAP_AKA_PRIME_K_AUT_LEN);
315 	pos += EAP_AKA_PRIME_K_AUT_LEN;
316 
317 	os_memcpy(k_re, pos, EAP_AKA_PRIME_K_RE_LEN);
318 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': K_re",
319 			k_re, EAP_AKA_PRIME_K_RE_LEN);
320 	pos += EAP_AKA_PRIME_K_RE_LEN;
321 
322 	os_memcpy(msk, pos, EAP_MSK_LEN);
323 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': MSK", msk, EAP_MSK_LEN);
324 	pos += EAP_MSK_LEN;
325 
326 	os_memcpy(emsk, pos, EAP_EMSK_LEN);
327 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': EMSK", emsk, EAP_EMSK_LEN);
328 }
329 
330 
331 int eap_aka_prime_derive_keys_reauth(const u8 *k_re, u16 counter,
332 				     const u8 *identity, size_t identity_len,
333 				     const u8 *nonce_s, u8 *msk, u8 *emsk)
334 {
335 	u8 seed3[2 + EAP_SIM_NONCE_S_LEN];
336 	u8 keys[EAP_MSK_LEN + EAP_EMSK_LEN];
337 	u8 *pos;
338 
339 	/*
340 	 * MK = PRF'(K_re,"EAP-AKA' re-auth"|Identity|counter|NONCE_S)
341 	 * MSK  = MK[0..511]
342 	 * EMSK = MK[512..1023]
343 	 */
344 
345 	WPA_PUT_BE16(seed3, counter);
346 	os_memcpy(seed3 + 2, nonce_s, EAP_SIM_NONCE_S_LEN);
347 
348 	prf_prime(k_re, "EAP-AKA' re-auth", identity, identity_len,
349 		  seed3, sizeof(seed3),
350 		  keys, sizeof(keys));
351 
352 	pos = keys;
353 	os_memcpy(msk, pos, EAP_MSK_LEN);
354 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': MSK", msk, EAP_MSK_LEN);
355 	pos += EAP_MSK_LEN;
356 
357 	os_memcpy(emsk, pos, EAP_EMSK_LEN);
358 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': EMSK", emsk, EAP_EMSK_LEN);
359 
360 	os_memset(keys, 0, sizeof(keys));
361 
362 	return 0;
363 }
364 
365 
366 int eap_sim_verify_mac_sha256(const u8 *k_aut, const struct wpabuf *req,
367 			      const u8 *mac, const u8 *extra, size_t extra_len)
368 {
369 	unsigned char hmac[SHA256_MAC_LEN];
370 	const u8 *addr[2];
371 	size_t len[2];
372 	u8 *tmp;
373 
374 	if (mac == NULL || wpabuf_len(req) < EAP_SIM_MAC_LEN ||
375 	    mac < wpabuf_head_u8(req) ||
376 	    mac > wpabuf_head_u8(req) + wpabuf_len(req) - EAP_SIM_MAC_LEN)
377 		return -1;
378 
379 	tmp = os_malloc(wpabuf_len(req));
380 	if (tmp == NULL)
381 		return -1;
382 
383 	addr[0] = tmp;
384 	len[0] = wpabuf_len(req);
385 	addr[1] = extra;
386 	len[1] = extra_len;
387 
388 	/* HMAC-SHA-256-128 */
389 	os_memcpy(tmp, wpabuf_head(req), wpabuf_len(req));
390 	os_memset(tmp + (mac - wpabuf_head_u8(req)), 0, EAP_SIM_MAC_LEN);
391 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Verify MAC - msg",
392 		    tmp, wpabuf_len(req));
393 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Verify MAC - extra data",
394 		    extra, extra_len);
395 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA': Verify MAC - K_aut",
396 			k_aut, EAP_AKA_PRIME_K_AUT_LEN);
397 	hmac_sha256_vector(k_aut, EAP_AKA_PRIME_K_AUT_LEN, 2, addr, len, hmac);
398 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Verify MAC: MAC",
399 		    hmac, EAP_SIM_MAC_LEN);
400 	os_free(tmp);
401 
402 	return (os_memcmp(hmac, mac, EAP_SIM_MAC_LEN) == 0) ? 0 : 1;
403 }
404 
405 
406 void eap_sim_add_mac_sha256(const u8 *k_aut, const u8 *msg, size_t msg_len,
407 			    u8 *mac, const u8 *extra, size_t extra_len)
408 {
409 	unsigned char hmac[SHA256_MAC_LEN];
410 	const u8 *addr[2];
411 	size_t len[2];
412 
413 	addr[0] = msg;
414 	len[0] = msg_len;
415 	addr[1] = extra;
416 	len[1] = extra_len;
417 
418 	/* HMAC-SHA-256-128 */
419 	os_memset(mac, 0, EAP_SIM_MAC_LEN);
420 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Add MAC - msg", msg, msg_len);
421 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Add MAC - extra data",
422 		    extra, extra_len);
423 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA': Add MAC - K_aut",
424 			k_aut, EAP_AKA_PRIME_K_AUT_LEN);
425 	hmac_sha256_vector(k_aut, EAP_AKA_PRIME_K_AUT_LEN, 2, addr, len, hmac);
426 	os_memcpy(mac, hmac, EAP_SIM_MAC_LEN);
427 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA': Add MAC: MAC",
428 		    mac, EAP_SIM_MAC_LEN);
429 }
430 
431 
432 void eap_aka_prime_derive_ck_ik_prime(u8 *ck, u8 *ik, const u8 *sqn_ak,
433 				      const u8 *network_name,
434 				      size_t network_name_len)
435 {
436 	u8 key[EAP_AKA_CK_LEN + EAP_AKA_IK_LEN];
437 	u8 hash[SHA256_MAC_LEN];
438 	const u8 *addr[5];
439 	size_t len[5];
440 	u8 fc;
441 	u8 l0[2], l1[2];
442 
443 	/* 3GPP TS 33.402 V8.0.0
444 	 * (CK', IK') = F(CK, IK, <access network identity>)
445 	 */
446 	/* TODO: CK', IK' generation should really be moved into the actual
447 	 * AKA procedure with network name passed in there and option to use
448 	 * AMF separation bit = 1 (3GPP TS 33.401). */
449 
450 	/* Change Request 33.402 CR 0033 to version 8.1.1 from
451 	 * 3GPP TSG-SA WG3 Meeting #53 in September 2008:
452 	 *
453 	 * CK' || IK' = HMAC-SHA-256(Key, S)
454 	 * S = FC || P0 || L0 || P1 || L1 || ... || Pn || Ln
455 	 * Key = CK || IK
456 	 * FC = 0x20
457 	 * P0 = access network identity (3GPP TS 24.302)
458 	 * L0 = length of acceess network identity (2 octets, big endian)
459 	 * P1 = SQN xor AK (if AK is not used, AK is treaded as 000..0
460 	 * L1 = 0x00 0x06
461 	 */
462 
463 	fc = 0x20;
464 
465 	wpa_printf(MSG_DEBUG, "EAP-AKA': Derive (CK',IK') from (CK,IK)");
466 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': CK", ck, EAP_AKA_CK_LEN);
467 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': IK", ik, EAP_AKA_IK_LEN);
468 	wpa_printf(MSG_DEBUG, "EAP-AKA': FC = 0x%x", fc);
469 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': P0 = Access network identity",
470 			  network_name, network_name_len);
471 	wpa_hexdump(MSG_DEBUG, "EAP-AKA': P1 = SQN xor AK", sqn_ak, 6);
472 
473 	os_memcpy(key, ck, EAP_AKA_CK_LEN);
474 	os_memcpy(key + EAP_AKA_CK_LEN, ik, EAP_AKA_IK_LEN);
475 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': Key = CK || IK",
476 			key, sizeof(key));
477 
478 	addr[0] = &fc;
479 	len[0] = 1;
480 	addr[1] = network_name;
481 	len[1] = network_name_len;
482 	WPA_PUT_BE16(l0, network_name_len);
483 	addr[2] = l0;
484 	len[2] = 2;
485 	addr[3] = sqn_ak;
486 	len[3] = 6;
487 	WPA_PUT_BE16(l1, 6);
488 	addr[4] = l1;
489 	len[4] = 2;
490 
491 	hmac_sha256_vector(key, sizeof(key), 5, addr, len, hash);
492 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': KDF output (CK' || IK')",
493 			hash, sizeof(hash));
494 
495 	os_memcpy(ck, hash, EAP_AKA_CK_LEN);
496 	os_memcpy(ik, hash + EAP_AKA_CK_LEN, EAP_AKA_IK_LEN);
497 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': CK'", ck, EAP_AKA_CK_LEN);
498 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA': IK'", ik, EAP_AKA_IK_LEN);
499 }
500 #endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
501 
502 
503 int eap_sim_parse_attr(const u8 *start, const u8 *end,
504 		       struct eap_sim_attrs *attr, int aka, int encr)
505 {
506 	const u8 *pos = start, *apos;
507 	size_t alen, plen, i, list_len;
508 
509 	os_memset(attr, 0, sizeof(*attr));
510 	attr->id_req = NO_ID_REQ;
511 	attr->notification = -1;
512 	attr->counter = -1;
513 	attr->selected_version = -1;
514 	attr->client_error_code = -1;
515 
516 	while (pos < end) {
517 		if (pos + 2 > end) {
518 			wpa_printf(MSG_INFO, "EAP-SIM: Attribute overflow(1)");
519 			return -1;
520 		}
521 		wpa_printf(MSG_MSGDUMP, "EAP-SIM: Attribute: Type=%d Len=%d",
522 			   pos[0], pos[1] * 4);
523 		if (pos + pos[1] * 4 > end) {
524 			wpa_printf(MSG_INFO, "EAP-SIM: Attribute overflow "
525 				   "(pos=%p len=%d end=%p)",
526 				   pos, pos[1] * 4, end);
527 			return -1;
528 		}
529 		if (pos[1] == 0) {
530 			wpa_printf(MSG_INFO, "EAP-SIM: Attribute underflow");
531 			return -1;
532 		}
533 		apos = pos + 2;
534 		alen = pos[1] * 4 - 2;
535 		wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Attribute data",
536 			    apos, alen);
537 
538 		switch (pos[0]) {
539 		case EAP_SIM_AT_RAND:
540 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_RAND");
541 			apos += 2;
542 			alen -= 2;
543 			if ((!aka && (alen % GSM_RAND_LEN)) ||
544 			    (aka && alen != EAP_AKA_RAND_LEN)) {
545 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_RAND"
546 					   " (len %lu)",
547 					   (unsigned long) alen);
548 				return -1;
549 			}
550 			attr->rand = apos;
551 			attr->num_chal = alen / GSM_RAND_LEN;
552 			break;
553 		case EAP_SIM_AT_AUTN:
554 			wpa_printf(MSG_DEBUG, "EAP-AKA: AT_AUTN");
555 			if (!aka) {
556 				wpa_printf(MSG_DEBUG, "EAP-SIM: "
557 					   "Unexpected AT_AUTN");
558 				return -1;
559 			}
560 			apos += 2;
561 			alen -= 2;
562 			if (alen != EAP_AKA_AUTN_LEN) {
563 				wpa_printf(MSG_INFO, "EAP-AKA: Invalid AT_AUTN"
564 					   " (len %lu)",
565 					   (unsigned long) alen);
566 				return -1;
567 			}
568 			attr->autn = apos;
569 			break;
570 		case EAP_SIM_AT_PADDING:
571 			if (!encr) {
572 				wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
573 					   "AT_PADDING");
574 				return -1;
575 			}
576 			wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) AT_PADDING");
577 			for (i = 2; i < alen; i++) {
578 				if (apos[i] != 0) {
579 					wpa_printf(MSG_INFO, "EAP-SIM: (encr) "
580 						   "AT_PADDING used a non-zero"
581 						   " padding byte");
582 					wpa_hexdump(MSG_DEBUG, "EAP-SIM: "
583 						    "(encr) padding bytes",
584 						    apos + 2, alen - 2);
585 					return -1;
586 				}
587 			}
588 			break;
589 		case EAP_SIM_AT_NONCE_MT:
590 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_NONCE_MT");
591 			if (alen != 2 + EAP_SIM_NONCE_MT_LEN) {
592 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
593 					   "AT_NONCE_MT length");
594 				return -1;
595 			}
596 			attr->nonce_mt = apos + 2;
597 			break;
598 		case EAP_SIM_AT_PERMANENT_ID_REQ:
599 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_PERMANENT_ID_REQ");
600 			attr->id_req = PERMANENT_ID;
601 			break;
602 		case EAP_SIM_AT_MAC:
603 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_MAC");
604 			if (alen != 2 + EAP_SIM_MAC_LEN) {
605 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_MAC "
606 					   "length");
607 				return -1;
608 			}
609 			attr->mac = apos + 2;
610 			break;
611 		case EAP_SIM_AT_NOTIFICATION:
612 			if (alen != 2) {
613 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
614 					   "AT_NOTIFICATION length %lu",
615 					   (unsigned long) alen);
616 				return -1;
617 			}
618 			attr->notification = apos[0] * 256 + apos[1];
619 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_NOTIFICATION %d",
620 				   attr->notification);
621 			break;
622 		case EAP_SIM_AT_ANY_ID_REQ:
623 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_ANY_ID_REQ");
624 			attr->id_req = ANY_ID;
625 			break;
626 		case EAP_SIM_AT_IDENTITY:
627 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_IDENTITY");
628 			plen = WPA_GET_BE16(apos);
629 			apos += 2;
630 			alen -= 2;
631 			if (plen > alen) {
632 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
633 					   "AT_IDENTITY (Actual Length %lu, "
634 					   "remaining length %lu)",
635 					   (unsigned long) plen,
636 					   (unsigned long) alen);
637 				return -1;
638 			}
639 
640 			attr->identity = apos;
641 			attr->identity_len = plen;
642 			break;
643 		case EAP_SIM_AT_VERSION_LIST:
644 			if (aka) {
645 				wpa_printf(MSG_DEBUG, "EAP-AKA: "
646 					   "Unexpected AT_VERSION_LIST");
647 				return -1;
648 			}
649 			list_len = apos[0] * 256 + apos[1];
650 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_VERSION_LIST");
651 			if (list_len < 2 || list_len > alen - 2) {
652 				wpa_printf(MSG_WARNING, "EAP-SIM: Invalid "
653 					   "AT_VERSION_LIST (list_len=%lu "
654 					   "attr_len=%lu)",
655 					   (unsigned long) list_len,
656 					   (unsigned long) alen);
657 				return -1;
658 			}
659 			attr->version_list = apos + 2;
660 			attr->version_list_len = list_len;
661 			break;
662 		case EAP_SIM_AT_SELECTED_VERSION:
663 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_SELECTED_VERSION");
664 			if (alen != 2) {
665 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
666 					   "AT_SELECTED_VERSION length %lu",
667 					   (unsigned long) alen);
668 				return -1;
669 			}
670 			attr->selected_version = apos[0] * 256 + apos[1];
671 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_SELECTED_VERSION "
672 				   "%d", attr->selected_version);
673 			break;
674 		case EAP_SIM_AT_FULLAUTH_ID_REQ:
675 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_FULLAUTH_ID_REQ");
676 			attr->id_req = FULLAUTH_ID;
677 			break;
678 		case EAP_SIM_AT_COUNTER:
679 			if (!encr) {
680 				wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
681 					   "AT_COUNTER");
682 				return -1;
683 			}
684 			if (alen != 2) {
685 				wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid "
686 					   "AT_COUNTER (alen=%lu)",
687 					   (unsigned long) alen);
688 				return -1;
689 			}
690 			attr->counter = apos[0] * 256 + apos[1];
691 			wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) AT_COUNTER %d",
692 				   attr->counter);
693 			break;
694 		case EAP_SIM_AT_COUNTER_TOO_SMALL:
695 			if (!encr) {
696 				wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
697 					   "AT_COUNTER_TOO_SMALL");
698 				return -1;
699 			}
700 			if (alen != 2) {
701 				wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid "
702 					   "AT_COUNTER_TOO_SMALL (alen=%lu)",
703 					   (unsigned long) alen);
704 				return -1;
705 			}
706 			wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
707 				   "AT_COUNTER_TOO_SMALL");
708 			attr->counter_too_small = 1;
709 			break;
710 		case EAP_SIM_AT_NONCE_S:
711 			if (!encr) {
712 				wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
713 					   "AT_NONCE_S");
714 				return -1;
715 			}
716 			wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
717 				   "AT_NONCE_S");
718 			if (alen != 2 + EAP_SIM_NONCE_S_LEN) {
719 				wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid "
720 					   "AT_NONCE_S (alen=%lu)",
721 					   (unsigned long) alen);
722 				return -1;
723 			}
724 			attr->nonce_s = apos + 2;
725 			break;
726 		case EAP_SIM_AT_CLIENT_ERROR_CODE:
727 			if (alen != 2) {
728 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
729 					   "AT_CLIENT_ERROR_CODE length %lu",
730 					   (unsigned long) alen);
731 				return -1;
732 			}
733 			attr->client_error_code = apos[0] * 256 + apos[1];
734 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_CLIENT_ERROR_CODE "
735 				   "%d", attr->client_error_code);
736 			break;
737 		case EAP_SIM_AT_IV:
738 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_IV");
739 			if (alen != 2 + EAP_SIM_MAC_LEN) {
740 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_IV "
741 					   "length %lu", (unsigned long) alen);
742 				return -1;
743 			}
744 			attr->iv = apos + 2;
745 			break;
746 		case EAP_SIM_AT_ENCR_DATA:
747 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_ENCR_DATA");
748 			attr->encr_data = apos + 2;
749 			attr->encr_data_len = alen - 2;
750 			if (attr->encr_data_len % 16) {
751 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
752 					   "AT_ENCR_DATA length %lu",
753 					   (unsigned long)
754 					   attr->encr_data_len);
755 				return -1;
756 			}
757 			break;
758 		case EAP_SIM_AT_NEXT_PSEUDONYM:
759 			if (!encr) {
760 				wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
761 					   "AT_NEXT_PSEUDONYM");
762 				return -1;
763 			}
764 			wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
765 				   "AT_NEXT_PSEUDONYM");
766 			plen = apos[0] * 256 + apos[1];
767 			if (plen > alen - 2) {
768 				wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid"
769 					   " AT_NEXT_PSEUDONYM (actual"
770 					   " len %lu, attr len %lu)",
771 					   (unsigned long) plen,
772 					   (unsigned long) alen);
773 				return -1;
774 			}
775 			attr->next_pseudonym = pos + 4;
776 			attr->next_pseudonym_len = plen;
777 			break;
778 		case EAP_SIM_AT_NEXT_REAUTH_ID:
779 			if (!encr) {
780 				wpa_printf(MSG_ERROR, "EAP-SIM: Unencrypted "
781 					   "AT_NEXT_REAUTH_ID");
782 				return -1;
783 			}
784 			wpa_printf(MSG_DEBUG, "EAP-SIM: (encr) "
785 				   "AT_NEXT_REAUTH_ID");
786 			plen = apos[0] * 256 + apos[1];
787 			if (plen > alen - 2) {
788 				wpa_printf(MSG_INFO, "EAP-SIM: (encr) Invalid"
789 					   " AT_NEXT_REAUTH_ID (actual"
790 					   " len %lu, attr len %lu)",
791 					   (unsigned long) plen,
792 					   (unsigned long) alen);
793 				return -1;
794 			}
795 			attr->next_reauth_id = pos + 4;
796 			attr->next_reauth_id_len = plen;
797 			break;
798 		case EAP_SIM_AT_RES:
799 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_RES");
800 			attr->res_len_bits = WPA_GET_BE16(apos);
801 			apos += 2;
802 			alen -= 2;
803 			if (!aka || alen < EAP_AKA_MIN_RES_LEN ||
804 			    alen > EAP_AKA_MAX_RES_LEN) {
805 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid AT_RES "
806 					   "(len %lu)",
807 					   (unsigned long) alen);
808 				return -1;
809 			}
810 			attr->res = apos;
811 			attr->res_len = alen;
812 			break;
813 		case EAP_SIM_AT_AUTS:
814 			wpa_printf(MSG_DEBUG, "EAP-AKA: AT_AUTS");
815 			if (!aka) {
816 				wpa_printf(MSG_DEBUG, "EAP-SIM: "
817 					   "Unexpected AT_AUTS");
818 				return -1;
819 			}
820 			if (alen != EAP_AKA_AUTS_LEN) {
821 				wpa_printf(MSG_INFO, "EAP-AKA: Invalid AT_AUTS"
822 					   " (len %lu)",
823 					   (unsigned long) alen);
824 				return -1;
825 			}
826 			attr->auts = apos;
827 			break;
828 		case EAP_SIM_AT_CHECKCODE:
829 			wpa_printf(MSG_DEBUG, "EAP-AKA: AT_CHECKCODE");
830 			if (!aka) {
831 				wpa_printf(MSG_DEBUG, "EAP-SIM: "
832 					   "Unexpected AT_CHECKCODE");
833 				return -1;
834 			}
835 			apos += 2;
836 			alen -= 2;
837 			if (alen != 0 && alen != EAP_AKA_CHECKCODE_LEN &&
838 			    alen != EAP_AKA_PRIME_CHECKCODE_LEN) {
839 				wpa_printf(MSG_INFO, "EAP-AKA: Invalid "
840 					   "AT_CHECKCODE (len %lu)",
841 					   (unsigned long) alen);
842 				return -1;
843 			}
844 			attr->checkcode = apos;
845 			attr->checkcode_len = alen;
846 			break;
847 		case EAP_SIM_AT_RESULT_IND:
848 			if (encr) {
849 				wpa_printf(MSG_ERROR, "EAP-SIM: Encrypted "
850 					   "AT_RESULT_IND");
851 				return -1;
852 			}
853 			if (alen != 2) {
854 				wpa_printf(MSG_INFO, "EAP-SIM: Invalid "
855 					   "AT_RESULT_IND (alen=%lu)",
856 					   (unsigned long) alen);
857 				return -1;
858 			}
859 			wpa_printf(MSG_DEBUG, "EAP-SIM: AT_RESULT_IND");
860 			attr->result_ind = 1;
861 			break;
862 #if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
863 		case EAP_SIM_AT_KDF_INPUT:
864 			if (aka != 2) {
865 				wpa_printf(MSG_INFO, "EAP-AKA: Unexpected "
866 					   "AT_KDF_INPUT");
867 				return -1;
868 			}
869 
870 			wpa_printf(MSG_DEBUG, "EAP-AKA: AT_KDF_INPUT");
871 			plen = WPA_GET_BE16(apos);
872 			apos += 2;
873 			alen -= 2;
874 			if (plen > alen) {
875 				wpa_printf(MSG_INFO, "EAP-AKA': Invalid "
876 					   "AT_KDF_INPUT (Actual Length %lu, "
877 					   "remaining length %lu)",
878 					   (unsigned long) plen,
879 					   (unsigned long) alen);
880 				return -1;
881 			}
882 			attr->kdf_input = apos;
883 			attr->kdf_input_len = plen;
884 			break;
885 		case EAP_SIM_AT_KDF:
886 			if (aka != 2) {
887 				wpa_printf(MSG_INFO, "EAP-AKA: Unexpected "
888 					   "AT_KDF");
889 				return -1;
890 			}
891 
892 			wpa_printf(MSG_DEBUG, "EAP-AKA: AT_KDF");
893 			if (alen != 2) {
894 				wpa_printf(MSG_INFO, "EAP-AKA': Invalid "
895 					   "AT_KDF (len %lu)",
896 					   (unsigned long) alen);
897 				return -1;
898 			}
899 			if (attr->kdf_count == EAP_AKA_PRIME_KDF_MAX) {
900 				wpa_printf(MSG_DEBUG, "EAP-AKA': Too many "
901 					   "AT_KDF attributes - ignore this");
902 				continue;
903 			}
904 			attr->kdf[attr->kdf_count] = WPA_GET_BE16(apos);
905 			attr->kdf_count++;
906 			break;
907 		case EAP_SIM_AT_BIDDING:
908 			wpa_printf(MSG_DEBUG, "EAP-AKA: AT_BIDDING");
909 			if (alen != 2) {
910 				wpa_printf(MSG_INFO, "EAP-AKA: Invalid "
911 					   "AT_BIDDING (len %lu)",
912 					   (unsigned long) alen);
913 				return -1;
914 			}
915 			attr->bidding = apos;
916 			break;
917 #endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
918 		default:
919 			if (pos[0] < 128) {
920 				wpa_printf(MSG_INFO, "EAP-SIM: Unrecognized "
921 					   "non-skippable attribute %d",
922 					   pos[0]);
923 				return -1;
924 			}
925 
926 			wpa_printf(MSG_DEBUG, "EAP-SIM: Unrecognized skippable"
927 				   " attribute %d ignored", pos[0]);
928 			break;
929 		}
930 
931 		pos += pos[1] * 4;
932 	}
933 
934 	wpa_printf(MSG_DEBUG, "EAP-SIM: Attributes parsed successfully "
935 		   "(aka=%d encr=%d)", aka, encr);
936 
937 	return 0;
938 }
939 
940 
941 u8 * eap_sim_parse_encr(const u8 *k_encr, const u8 *encr_data,
942 			size_t encr_data_len, const u8 *iv,
943 			struct eap_sim_attrs *attr, int aka)
944 {
945 	u8 *decrypted;
946 
947 	if (!iv) {
948 		wpa_printf(MSG_INFO, "EAP-SIM: Encrypted data, but no IV");
949 		return NULL;
950 	}
951 
952 	decrypted = os_malloc(encr_data_len);
953 	if (decrypted == NULL)
954 		return NULL;
955 	os_memcpy(decrypted, encr_data, encr_data_len);
956 
957 	if (aes_128_cbc_decrypt(k_encr, iv, decrypted, encr_data_len)) {
958 		os_free(decrypted);
959 		return NULL;
960 	}
961 	wpa_hexdump(MSG_MSGDUMP, "EAP-SIM: Decrypted AT_ENCR_DATA",
962 		    decrypted, encr_data_len);
963 
964 	if (eap_sim_parse_attr(decrypted, decrypted + encr_data_len, attr,
965 			       aka, 1)) {
966 		wpa_printf(MSG_INFO, "EAP-SIM: (encr) Failed to parse "
967 			   "decrypted AT_ENCR_DATA");
968 		os_free(decrypted);
969 		return NULL;
970 	}
971 
972 	return decrypted;
973 }
974 
975 
976 #define EAP_SIM_INIT_LEN 128
977 
978 struct eap_sim_msg {
979 	struct wpabuf *buf;
980 	size_t mac, iv, encr; /* index from buf */
981 	int type;
982 };
983 
984 
985 struct eap_sim_msg * eap_sim_msg_init(int code, int id, int type, int subtype)
986 {
987 	struct eap_sim_msg *msg;
988 	struct eap_hdr *eap;
989 	u8 *pos;
990 
991 	msg = os_zalloc(sizeof(*msg));
992 	if (msg == NULL)
993 		return NULL;
994 
995 	msg->type = type;
996 	msg->buf = wpabuf_alloc(EAP_SIM_INIT_LEN);
997 	if (msg->buf == NULL) {
998 		os_free(msg);
999 		return NULL;
1000 	}
1001 	eap = wpabuf_put(msg->buf, sizeof(*eap));
1002 	eap->code = code;
1003 	eap->identifier = id;
1004 
1005 	pos = wpabuf_put(msg->buf, 4);
1006 	*pos++ = type;
1007 	*pos++ = subtype;
1008 	*pos++ = 0; /* Reserved */
1009 	*pos++ = 0; /* Reserved */
1010 
1011 	return msg;
1012 }
1013 
1014 
1015 struct wpabuf * eap_sim_msg_finish(struct eap_sim_msg *msg, const u8 *k_aut,
1016 				   const u8 *extra, size_t extra_len)
1017 {
1018 	struct eap_hdr *eap;
1019 	struct wpabuf *buf;
1020 
1021 	if (msg == NULL)
1022 		return NULL;
1023 
1024 	eap = wpabuf_mhead(msg->buf);
1025 	eap->length = host_to_be16(wpabuf_len(msg->buf));
1026 
1027 #if defined(EAP_AKA_PRIME) || defined(EAP_SERVER_AKA_PRIME)
1028 	if (k_aut && msg->mac && msg->type == EAP_TYPE_AKA_PRIME) {
1029 		eap_sim_add_mac_sha256(k_aut, (u8 *) wpabuf_head(msg->buf),
1030 				       wpabuf_len(msg->buf),
1031 				       (u8 *) wpabuf_mhead(msg->buf) +
1032 				       msg->mac, extra, extra_len);
1033 	} else
1034 #endif /* EAP_AKA_PRIME || EAP_SERVER_AKA_PRIME */
1035 	if (k_aut && msg->mac) {
1036 		eap_sim_add_mac(k_aut, (u8 *) wpabuf_head(msg->buf),
1037 				wpabuf_len(msg->buf),
1038 				(u8 *) wpabuf_mhead(msg->buf) + msg->mac,
1039 				extra, extra_len);
1040 	}
1041 
1042 	buf = msg->buf;
1043 	os_free(msg);
1044 	return buf;
1045 }
1046 
1047 
1048 void eap_sim_msg_free(struct eap_sim_msg *msg)
1049 {
1050 	if (msg) {
1051 		wpabuf_free(msg->buf);
1052 		os_free(msg);
1053 	}
1054 }
1055 
1056 
1057 u8 * eap_sim_msg_add_full(struct eap_sim_msg *msg, u8 attr,
1058 			  const u8 *data, size_t len)
1059 {
1060 	int attr_len = 2 + len;
1061 	int pad_len;
1062 	u8 *start;
1063 
1064 	if (msg == NULL)
1065 		return NULL;
1066 
1067 	pad_len = (4 - attr_len % 4) % 4;
1068 	attr_len += pad_len;
1069 	if (wpabuf_resize(&msg->buf, attr_len))
1070 		return NULL;
1071 	start = wpabuf_put(msg->buf, 0);
1072 	wpabuf_put_u8(msg->buf, attr);
1073 	wpabuf_put_u8(msg->buf, attr_len / 4);
1074 	wpabuf_put_data(msg->buf, data, len);
1075 	if (pad_len)
1076 		os_memset(wpabuf_put(msg->buf, pad_len), 0, pad_len);
1077 	return start;
1078 }
1079 
1080 
1081 u8 * eap_sim_msg_add(struct eap_sim_msg *msg, u8 attr, u16 value,
1082 		     const u8 *data, size_t len)
1083 {
1084 	int attr_len = 4 + len;
1085 	int pad_len;
1086 	u8 *start;
1087 
1088 	if (msg == NULL)
1089 		return NULL;
1090 
1091 	pad_len = (4 - attr_len % 4) % 4;
1092 	attr_len += pad_len;
1093 	if (wpabuf_resize(&msg->buf, attr_len))
1094 		return NULL;
1095 	start = wpabuf_put(msg->buf, 0);
1096 	wpabuf_put_u8(msg->buf, attr);
1097 	wpabuf_put_u8(msg->buf, attr_len / 4);
1098 	wpabuf_put_be16(msg->buf, value);
1099 	if (data)
1100 		wpabuf_put_data(msg->buf, data, len);
1101 	else
1102 		wpabuf_put(msg->buf, len);
1103 	if (pad_len)
1104 		os_memset(wpabuf_put(msg->buf, pad_len), 0, pad_len);
1105 	return start;
1106 }
1107 
1108 
1109 u8 * eap_sim_msg_add_mac(struct eap_sim_msg *msg, u8 attr)
1110 {
1111 	u8 *pos = eap_sim_msg_add(msg, attr, 0, NULL, EAP_SIM_MAC_LEN);
1112 	if (pos)
1113 		msg->mac = (pos - wpabuf_head_u8(msg->buf)) + 4;
1114 	return pos;
1115 }
1116 
1117 
1118 int eap_sim_msg_add_encr_start(struct eap_sim_msg *msg, u8 attr_iv,
1119 			       u8 attr_encr)
1120 {
1121 	u8 *pos = eap_sim_msg_add(msg, attr_iv, 0, NULL, EAP_SIM_IV_LEN);
1122 	if (pos == NULL)
1123 		return -1;
1124 	msg->iv = (pos - wpabuf_head_u8(msg->buf)) + 4;
1125 	if (random_get_bytes(wpabuf_mhead_u8(msg->buf) + msg->iv,
1126 			     EAP_SIM_IV_LEN)) {
1127 		msg->iv = 0;
1128 		return -1;
1129 	}
1130 
1131 	pos = eap_sim_msg_add(msg, attr_encr, 0, NULL, 0);
1132 	if (pos == NULL) {
1133 		msg->iv = 0;
1134 		return -1;
1135 	}
1136 	msg->encr = pos - wpabuf_head_u8(msg->buf);
1137 
1138 	return 0;
1139 }
1140 
1141 
1142 int eap_sim_msg_add_encr_end(struct eap_sim_msg *msg, u8 *k_encr, int attr_pad)
1143 {
1144 	size_t encr_len;
1145 
1146 	if (msg == NULL || k_encr == NULL || msg->iv == 0 || msg->encr == 0)
1147 		return -1;
1148 
1149 	encr_len = wpabuf_len(msg->buf) - msg->encr - 4;
1150 	if (encr_len % 16) {
1151 		u8 *pos;
1152 		int pad_len = 16 - (encr_len % 16);
1153 		if (pad_len < 4) {
1154 			wpa_printf(MSG_WARNING, "EAP-SIM: "
1155 				   "eap_sim_msg_add_encr_end - invalid pad_len"
1156 				   " %d", pad_len);
1157 			return -1;
1158 		}
1159 		wpa_printf(MSG_DEBUG, "   *AT_PADDING");
1160 		pos = eap_sim_msg_add(msg, attr_pad, 0, NULL, pad_len - 4);
1161 		if (pos == NULL)
1162 			return -1;
1163 		os_memset(pos + 4, 0, pad_len - 4);
1164 		encr_len += pad_len;
1165 	}
1166 	wpa_printf(MSG_DEBUG, "   (AT_ENCR_DATA data len %lu)",
1167 		   (unsigned long) encr_len);
1168 	wpabuf_mhead_u8(msg->buf)[msg->encr + 1] = encr_len / 4 + 1;
1169 	return aes_128_cbc_encrypt(k_encr, wpabuf_head_u8(msg->buf) + msg->iv,
1170 				   wpabuf_mhead_u8(msg->buf) + msg->encr + 4,
1171 				   encr_len);
1172 }
1173 
1174 
1175 void eap_sim_report_notification(void *msg_ctx, int notification, int aka)
1176 {
1177 #ifndef CONFIG_NO_STDOUT_DEBUG
1178 	const char *type = aka ? "AKA" : "SIM";
1179 #endif /* CONFIG_NO_STDOUT_DEBUG */
1180 
1181 	switch (notification) {
1182 	case EAP_SIM_GENERAL_FAILURE_AFTER_AUTH:
1183 		wpa_printf(MSG_WARNING, "EAP-%s: General failure "
1184 			   "notification (after authentication)", type);
1185 		break;
1186 	case EAP_SIM_TEMPORARILY_DENIED:
1187 		wpa_printf(MSG_WARNING, "EAP-%s: Failure notification: "
1188 			   "User has been temporarily denied access to the "
1189 			   "requested service", type);
1190 		break;
1191 	case EAP_SIM_NOT_SUBSCRIBED:
1192 		wpa_printf(MSG_WARNING, "EAP-%s: Failure notification: "
1193 			   "User has not subscribed to the requested service",
1194 			   type);
1195 		break;
1196 	case EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH:
1197 		wpa_printf(MSG_WARNING, "EAP-%s: General failure "
1198 			   "notification (before authentication)", type);
1199 		break;
1200 	case EAP_SIM_SUCCESS:
1201 		wpa_printf(MSG_INFO, "EAP-%s: Successful authentication "
1202 			   "notification", type);
1203 		break;
1204 	default:
1205 		if (notification >= 32768) {
1206 			wpa_printf(MSG_INFO, "EAP-%s: Unrecognized "
1207 				   "non-failure notification %d",
1208 				   type, notification);
1209 		} else {
1210 			wpa_printf(MSG_WARNING, "EAP-%s: Unrecognized "
1211 				   "failure notification %d",
1212 				   type, notification);
1213 		}
1214 	}
1215 }
1216