2 * EAP peer method: EAP-pwd (RFC 5931)
3 * Copyright (c) 2010, Dan Harkins <dharkins@lounge.org>
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
12 #include "crypto/sha1.h"
13 #include "crypto/sha256.h"
14 #include "crypto/sha512.h"
15 #include "crypto/ms_funcs.h"
16 #include "crypto/crypto.h"
17 #include "eap_peer/eap_i.h"
18 #include "eap_common/eap_pwd_common.h"
23 PWD_ID_Req, PWD_Commit_Req, PWD_Confirm_Req,
24 SUCCESS_ON_FRAG_COMPLETION, SUCCESS, FAILURE
40 struct wpabuf *outbuf;
44 struct crypto_bignum *k;
45 struct crypto_bignum *private_value;
46 struct crypto_bignum *server_scalar;
47 struct crypto_bignum *my_scalar;
48 struct crypto_ec_point *my_element;
49 struct crypto_ec_point *server_element;
52 u8 emsk[EAP_EMSK_LEN];
53 u8 session_id[1 + SHA256_MAC_LEN];
57 #ifndef CONFIG_NO_STDOUT_DEBUG
58 static const char * eap_pwd_state_txt(int state)
64 return "PWD-Commit-Req";
66 return "PWD-Confirm-Req";
67 case SUCCESS_ON_FRAG_COMPLETION:
68 return "SUCCESS_ON_FRAG_COMPLETION";
77 #endif /* CONFIG_NO_STDOUT_DEBUG */
80 static void eap_pwd_state(struct eap_pwd_data *data, int state)
82 wpa_printf(MSG_DEBUG, "EAP-PWD: %s -> %s",
83 eap_pwd_state_txt(data->state), eap_pwd_state_txt(state));
88 static void * eap_pwd_init(struct eap_sm *sm)
90 struct eap_pwd_data *data;
91 const u8 *identity, *password;
92 size_t identity_len, password_len;
96 password = eap_get_config_password2(sm, &password_len, &pwhash);
97 if (password == NULL) {
98 wpa_printf(MSG_INFO, "EAP-PWD: No password configured!");
102 identity = eap_get_config_identity(sm, &identity_len);
103 if (identity == NULL) {
104 wpa_printf(MSG_INFO, "EAP-PWD: No identity configured!");
108 if ((data = os_zalloc(sizeof(*data))) == NULL) {
109 wpa_printf(MSG_INFO, "EAP-PWD: memory allocation data fail");
113 if ((data->id_peer = os_malloc(identity_len)) == NULL) {
114 wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
119 os_memcpy(data->id_peer, identity, identity_len);
120 data->id_peer_len = identity_len;
122 if ((data->password = os_malloc(password_len)) == NULL) {
123 wpa_printf(MSG_INFO, "EAP-PWD: memory allocation psk fail");
124 bin_clear_free(data->id_peer, data->id_peer_len);
128 os_memcpy(data->password, password, password_len);
129 data->password_len = password_len;
130 data->password_hash = pwhash;
132 data->out_frag_pos = data->in_frag_pos = 0;
133 data->inbuf = data->outbuf = NULL;
134 fragment_size = eap_get_config_fragment_size(sm);
135 if (fragment_size <= 0)
136 data->mtu = 1020; /* default from RFC 5931 */
138 data->mtu = fragment_size;
140 data->state = PWD_ID_Req;
146 static void eap_pwd_deinit(struct eap_sm *sm, void *priv)
148 struct eap_pwd_data *data = priv;
150 crypto_bignum_deinit(data->private_value, 1);
151 crypto_bignum_deinit(data->server_scalar, 1);
152 crypto_bignum_deinit(data->my_scalar, 1);
153 crypto_bignum_deinit(data->k, 1);
154 crypto_ec_point_deinit(data->my_element, 1);
155 crypto_ec_point_deinit(data->server_element, 1);
156 bin_clear_free(data->id_peer, data->id_peer_len);
157 bin_clear_free(data->id_server, data->id_server_len);
158 bin_clear_free(data->password, data->password_len);
160 crypto_ec_deinit(data->grp->group);
161 crypto_ec_point_deinit(data->grp->pwe, 1);
164 wpabuf_free(data->inbuf);
165 wpabuf_free(data->outbuf);
166 bin_clear_free(data, sizeof(*data));
170 static u8 * eap_pwd_getkey(struct eap_sm *sm, void *priv, size_t *len)
172 struct eap_pwd_data *data = priv;
175 if (data->state != SUCCESS)
178 key = os_memdup(data->msk, EAP_MSK_LEN);
188 static u8 * eap_pwd_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
190 struct eap_pwd_data *data = priv;
193 if (data->state != SUCCESS)
196 id = os_memdup(data->session_id, 1 + SHA256_MAC_LEN);
200 *len = 1 + SHA256_MAC_LEN;
207 eap_pwd_perform_id_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
208 struct eap_method_ret *ret,
209 const struct wpabuf *reqData,
210 const u8 *payload, size_t payload_len)
212 struct eap_pwd_id *id;
214 if (data->state != PWD_ID_Req) {
216 eap_pwd_state(data, FAILURE);
220 if (payload_len < sizeof(struct eap_pwd_id)) {
222 eap_pwd_state(data, FAILURE);
226 id = (struct eap_pwd_id *) payload;
227 data->group_num = be_to_host16(id->group_num);
228 wpa_printf(MSG_DEBUG,
229 "EAP-PWD: Server EAP-pwd-ID proposal: group=%u random=%u prf=%u prep=%u",
230 data->group_num, id->random_function, id->prf, id->prep);
231 if ((id->random_function != EAP_PWD_DEFAULT_RAND_FUNC) ||
232 (id->prf != EAP_PWD_DEFAULT_PRF)) {
234 eap_pwd_state(data, FAILURE);
238 if (id->prep != EAP_PWD_PREP_NONE &&
239 id->prep != EAP_PWD_PREP_MS &&
240 id->prep != EAP_PWD_PREP_SSHA1 &&
241 id->prep != EAP_PWD_PREP_SSHA256 &&
242 id->prep != EAP_PWD_PREP_SSHA512) {
243 wpa_printf(MSG_DEBUG,
244 "EAP-PWD: Unsupported password pre-processing technique (Prep=%u)",
246 eap_pwd_state(data, FAILURE);
250 if (id->prep == EAP_PWD_PREP_NONE && data->password_hash) {
251 wpa_printf(MSG_DEBUG,
252 "EAP-PWD: Unhashed password not available");
253 eap_pwd_state(data, FAILURE);
257 wpa_printf(MSG_DEBUG, "EAP-PWD (peer): using group %d",
260 data->prep = id->prep;
261 os_memcpy(data->token, id->token, sizeof(id->token));
263 if (data->id_server || data->grp) {
264 wpa_printf(MSG_INFO, "EAP-pwd: data was already allocated");
265 eap_pwd_state(data, FAILURE);
269 data->id_server = os_malloc(payload_len - sizeof(struct eap_pwd_id));
270 if (data->id_server == NULL) {
271 wpa_printf(MSG_INFO, "EAP-PWD: memory allocation id fail");
272 eap_pwd_state(data, FAILURE);
275 data->id_server_len = payload_len - sizeof(struct eap_pwd_id);
276 os_memcpy(data->id_server, id->identity, data->id_server_len);
277 wpa_hexdump_ascii(MSG_INFO, "EAP-PWD (peer): server sent id of",
278 data->id_server, data->id_server_len);
280 data->grp = get_eap_pwd_group(data->group_num);
281 if (data->grp == NULL) {
282 wpa_printf(MSG_INFO, "EAP-PWD: failed to allocate memory for "
284 eap_pwd_state(data, FAILURE);
288 data->outbuf = wpabuf_alloc(sizeof(struct eap_pwd_id) +
290 if (data->outbuf == NULL) {
291 eap_pwd_state(data, FAILURE);
294 wpabuf_put_be16(data->outbuf, data->group_num);
295 wpabuf_put_u8(data->outbuf, EAP_PWD_DEFAULT_RAND_FUNC);
296 wpabuf_put_u8(data->outbuf, EAP_PWD_DEFAULT_PRF);
297 wpabuf_put_data(data->outbuf, id->token, sizeof(id->token));
298 wpabuf_put_u8(data->outbuf, id->prep);
299 wpabuf_put_data(data->outbuf, data->id_peer, data->id_peer_len);
301 eap_pwd_state(data, PWD_Commit_Req);
306 eap_pwd_perform_commit_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
307 struct eap_method_ret *ret,
308 const struct wpabuf *reqData,
309 const u8 *payload, size_t payload_len)
311 struct crypto_ec_point *K = NULL, *point = NULL;
312 struct crypto_bignum *mask = NULL, *cofactor = NULL;
313 const u8 *ptr = payload;
314 u8 *scalar = NULL, *element = NULL;
315 size_t prime_len, order_len;
319 const u8 *salt_pwd[2];
320 size_t salt_pwd_len[2], exp_len;
321 u8 salt_len, salthashpwd[64]; /* 64 = SHA512_DIGEST_LENGTH */
324 if (data->state != PWD_Commit_Req) {
330 wpa_printf(MSG_DEBUG,
331 "EAP-PWD (client): uninitialized EAP-pwd group");
336 prime_len = crypto_ec_prime_len(data->grp->group);
337 order_len = crypto_ec_order_len(data->grp->group);
339 switch (data->prep) {
340 case EAP_PWD_PREP_MS:
341 wpa_printf(MSG_DEBUG,
342 "EAP-pwd commit request, password prep is MS");
344 wpa_printf(MSG_ERROR,
345 "EAP-PWD (peer): MS password hash not supported in FIPS mode");
346 eap_pwd_state(data, FAILURE);
348 #else /* CONFIG_FIPS */
349 if (payload_len != 2 * prime_len + order_len) {
351 "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
352 (unsigned int) payload_len,
353 (unsigned int) (2 * prime_len + order_len));
356 if (data->password_hash) {
357 res = hash_nt_password_hash(data->password, pwhashhash);
361 res = nt_password_hash(data->password,
362 data->password_len, pwhash);
364 res = hash_nt_password_hash(pwhash, pwhashhash);
365 os_memset(pwhash, 0, sizeof(pwhash));
369 eap_pwd_state(data, FAILURE);
373 password = pwhashhash;
374 password_len = sizeof(pwhashhash);
375 #endif /* CONFIG_FIPS */
377 case EAP_PWD_PREP_SSHA1:
378 wpa_printf(MSG_DEBUG,
379 "EAP-pwd commit request, password prep is salted sha1");
380 if (payload_len < 1 || *ptr == 0) {
381 wpa_printf(MSG_DEBUG, "EAP-pwd: Invalid Salt-len");
385 exp_len = 1 + salt_len + 2 * prime_len + order_len;
386 if (payload_len != exp_len) {
388 "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
389 (unsigned int) payload_len,
390 (unsigned int) exp_len);
394 /* salted-password = Hash(password | salt) */
395 wpa_hexdump_key(MSG_DEBUG, "EAP-pwd: Unsalted password",
396 data->password, data->password_len);
397 wpa_hexdump(MSG_DEBUG, "EAP-pwd: Salt", ptr, salt_len);
398 salt_pwd[0] = data->password;
400 salt_pwd_len[0] = data->password_len;
401 salt_pwd_len[1] = salt_len;
402 if (sha1_vector(2, salt_pwd, salt_pwd_len, salthashpwd) < 0)
405 wpa_printf(MSG_DEBUG,
406 "EAP-pwd: sha1 hashed %d byte salt with password",
409 password = salthashpwd;
410 password_len = SHA1_MAC_LEN;
411 wpa_hexdump_key(MSG_DEBUG, "EAP-pwd: Salted password",
412 password, password_len);
414 case EAP_PWD_PREP_SSHA256:
415 wpa_printf(MSG_DEBUG,
416 "EAP-pwd commit request, password prep is salted sha256");
417 if (payload_len < 1 || *ptr == 0) {
418 wpa_printf(MSG_DEBUG, "EAP-pwd: Invalid Salt-len");
422 exp_len = 1 + salt_len + 2 * prime_len + order_len;
423 if (payload_len != exp_len) {
425 "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
426 (unsigned int) payload_len,
427 (unsigned int) exp_len);
431 /* salted-password = Hash(password | salt) */
432 wpa_hexdump_key(MSG_DEBUG, "EAP-pwd: Unsalted password",
433 data->password, data->password_len);
434 wpa_hexdump(MSG_DEBUG, "EAP-pwd: Salt", ptr, salt_len);
435 salt_pwd[0] = data->password;
437 salt_pwd_len[0] = data->password_len;
438 salt_pwd_len[1] = salt_len;
439 if (sha256_vector(2, salt_pwd, salt_pwd_len, salthashpwd) < 0)
443 password = salthashpwd;
444 password_len = SHA256_MAC_LEN;
445 wpa_hexdump_key(MSG_DEBUG, "EAP-pwd: Salted password",
446 password, password_len);
449 case EAP_PWD_PREP_SSHA512:
450 wpa_printf(MSG_DEBUG,
451 "EAP-pwd commit request, password prep is salted sha512");
452 if (payload_len < 1 || *ptr == 0) {
453 wpa_printf(MSG_DEBUG, "EAP-pwd: Invalid Salt-len");
457 exp_len = 1 + salt_len + 2 * prime_len + order_len;
458 if (payload_len != exp_len) {
460 "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
461 (unsigned int) payload_len,
462 (unsigned int) exp_len);
466 /* salted-password = Hash(password | salt) */
467 wpa_hexdump_key(MSG_DEBUG, "EAP-pwd: Unsalted password",
468 data->password, data->password_len);
469 wpa_hexdump(MSG_DEBUG, "EAP-pwd: Salt", ptr, salt_len);
470 salt_pwd[0] = data->password;
472 salt_pwd_len[0] = data->password_len;
473 salt_pwd_len[1] = salt_len;
474 if (sha512_vector(2, salt_pwd, salt_pwd_len, salthashpwd) < 0)
478 password = salthashpwd;
479 password_len = SHA512_MAC_LEN;
480 wpa_hexdump_key(MSG_DEBUG, "EAP-pwd: Salted password",
481 password, password_len);
483 #endif /* CONFIG_SHA512 */
484 case EAP_PWD_PREP_NONE:
485 wpa_printf(MSG_DEBUG,
486 "EAP-pwd commit request, password prep is NONE");
487 if (data->password_hash) {
488 wpa_printf(MSG_DEBUG,
489 "EAP-PWD: Unhashed password not available");
490 eap_pwd_state(data, FAILURE);
493 if (payload_len != 2 * prime_len + order_len) {
495 "EAP-pwd: Unexpected Commit payload length %u (expected %u)",
496 (unsigned int) payload_len,
497 (unsigned int) (2 * prime_len + order_len));
500 password = data->password;
501 password_len = data->password_len;
504 wpa_printf(MSG_DEBUG,
505 "EAP-pwd: Unsupported password pre-processing technique (Prep=%u)",
507 eap_pwd_state(data, FAILURE);
512 res = compute_password_element(data->grp, data->group_num,
513 password, password_len,
514 data->id_server, data->id_server_len,
515 data->id_peer, data->id_peer_len,
517 os_memset(pwhashhash, 0, sizeof(pwhashhash));
518 os_memset(salthashpwd, 0, sizeof(salthashpwd));
520 wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute PWE");
521 eap_pwd_state(data, FAILURE);
525 wpa_printf(MSG_DEBUG, "EAP-PWD (peer): computed %d bit PWE...",
526 (int) crypto_ec_prime_len_bits(data->grp->group));
528 data->private_value = crypto_bignum_init();
529 data->my_element = crypto_ec_point_init(data->grp->group);
530 cofactor = crypto_bignum_init();
531 data->my_scalar = crypto_bignum_init();
532 mask = crypto_bignum_init();
533 if (!data->private_value || !data->my_element || !cofactor ||
534 !data->my_scalar || !mask) {
535 wpa_printf(MSG_INFO, "EAP-PWD (peer): scalar allocation fail");
539 if (crypto_ec_cofactor(data->grp->group, cofactor) < 0) {
540 wpa_printf(MSG_INFO, "EAP-pwd (peer): unable to get cofactor "
545 if (crypto_bignum_rand(data->private_value,
546 crypto_ec_get_order(data->grp->group)) < 0 ||
547 crypto_bignum_rand(mask,
548 crypto_ec_get_order(data->grp->group)) < 0 ||
549 crypto_bignum_add(data->private_value, mask,
550 data->my_scalar) < 0 ||
551 crypto_bignum_mod(data->my_scalar,
552 crypto_ec_get_order(data->grp->group),
553 data->my_scalar) < 0) {
555 "EAP-pwd (peer): unable to get randomness");
559 if (crypto_ec_point_mul(data->grp->group, data->grp->pwe, mask,
560 data->my_element) < 0) {
561 wpa_printf(MSG_INFO, "EAP-PWD (peer): element allocation "
563 eap_pwd_state(data, FAILURE);
567 if (crypto_ec_point_invert(data->grp->group, data->my_element) < 0) {
568 wpa_printf(MSG_INFO, "EAP-PWD (peer): element inversion fail");
572 /* process the request */
573 data->k = crypto_bignum_init();
574 K = crypto_ec_point_init(data->grp->group);
575 point = crypto_ec_point_init(data->grp->group);
576 if (!data->k || !K || !point) {
577 wpa_printf(MSG_INFO, "EAP-PWD (peer): peer data allocation "
582 /* element, x then y, followed by scalar */
583 data->server_element = crypto_ec_point_from_bin(data->grp->group, ptr);
584 if (!data->server_element) {
585 wpa_printf(MSG_INFO, "EAP-PWD (peer): setting peer element "
589 ptr += prime_len * 2;
590 data->server_scalar = crypto_bignum_init_set(ptr, order_len);
591 if (!data->server_scalar) {
593 "EAP-PWD (peer): setting peer scalar fail");
597 /* check to ensure server's element is not in a small sub-group */
598 if (!crypto_bignum_is_one(cofactor)) {
599 if (crypto_ec_point_mul(data->grp->group, data->server_element,
600 cofactor, point) < 0) {
601 wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
602 "server element by order!\n");
605 if (crypto_ec_point_is_at_infinity(data->grp->group, point)) {
606 wpa_printf(MSG_INFO, "EAP-PWD (peer): server element "
607 "is at infinity!\n");
612 /* compute the shared key, k */
613 if (crypto_ec_point_mul(data->grp->group, data->grp->pwe,
614 data->server_scalar, K) < 0 ||
615 crypto_ec_point_add(data->grp->group, K, data->server_element,
617 crypto_ec_point_mul(data->grp->group, K, data->private_value,
619 wpa_printf(MSG_INFO, "EAP-PWD (peer): computing shared key "
624 /* ensure that the shared key isn't in a small sub-group */
625 if (!crypto_bignum_is_one(cofactor)) {
626 if (crypto_ec_point_mul(data->grp->group, K, cofactor, K) < 0) {
627 wpa_printf(MSG_INFO, "EAP-PWD (peer): cannot multiply "
628 "shared key point by order");
634 * This check is strictly speaking just for the case above where
635 * co-factor > 1 but it was suggested that even though this is probably
636 * never going to happen it is a simple and safe check "just to be
637 * sure" so let's be safe.
639 if (crypto_ec_point_is_at_infinity(data->grp->group, K)) {
640 wpa_printf(MSG_INFO, "EAP-PWD (peer): shared key point is at "
645 if (crypto_ec_point_x(data->grp->group, K, data->k) < 0) {
646 wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to extract "
647 "shared secret from point");
651 /* now do the response */
652 scalar = os_zalloc(order_len);
653 element = os_zalloc(prime_len * 2);
654 if (!scalar || !element) {
655 wpa_printf(MSG_INFO, "EAP-PWD (peer): data allocation fail");
660 * bignums occupy as little memory as possible so one that is
661 * sufficiently smaller than the prime or order might need pre-pending
664 crypto_bignum_to_bin(data->my_scalar, scalar, order_len, order_len);
665 if (crypto_ec_point_to_bin(data->grp->group, data->my_element, element,
666 element + prime_len) != 0) {
667 wpa_printf(MSG_INFO, "EAP-PWD (peer): point assignment fail");
671 data->outbuf = wpabuf_alloc(order_len + 2 * prime_len);
672 if (data->outbuf == NULL)
675 /* we send the element as (x,y) follwed by the scalar */
676 wpabuf_put_data(data->outbuf, element, 2 * prime_len);
677 wpabuf_put_data(data->outbuf, scalar, order_len);
682 crypto_bignum_deinit(mask, 1);
683 crypto_bignum_deinit(cofactor, 1);
684 crypto_ec_point_deinit(K, 1);
685 crypto_ec_point_deinit(point, 1);
686 if (data->outbuf == NULL)
687 eap_pwd_state(data, FAILURE);
689 eap_pwd_state(data, PWD_Confirm_Req);
694 eap_pwd_perform_confirm_exchange(struct eap_sm *sm, struct eap_pwd_data *data,
695 struct eap_method_ret *ret,
696 const struct wpabuf *reqData,
697 const u8 *payload, size_t payload_len)
699 struct crypto_hash *hash = NULL;
702 u8 conf[SHA256_MAC_LEN], *cruft = NULL, *ptr;
703 size_t prime_len = 0, order_len = 0;
705 if (data->state != PWD_Confirm_Req) {
710 if (payload_len != SHA256_MAC_LEN) {
712 "EAP-pwd: Unexpected Confirm payload length %u (expected %u)",
713 (unsigned int) payload_len, SHA256_MAC_LEN);
717 prime_len = crypto_ec_prime_len(data->grp->group);
718 order_len = crypto_ec_order_len(data->grp->group);
721 * first build up the ciphersuite which is group | random_function |
724 grp = htons(data->group_num);
726 os_memcpy(ptr, &grp, sizeof(u16));
728 *ptr = EAP_PWD_DEFAULT_RAND_FUNC;
730 *ptr = EAP_PWD_DEFAULT_PRF;
732 /* each component of the point will be at most as big as the prime */
733 cruft = os_malloc(prime_len * 2);
735 wpa_printf(MSG_INFO, "EAP-PWD (server): confirm allocation "
741 * server's commit is H(k | server_element | server_scalar |
742 * peer_element | peer_scalar | ciphersuite)
744 hash = eap_pwd_h_init();
749 * zero the memory each time because this is mod prime math and some
750 * value may start with a few zeros and the previous one did not.
752 crypto_bignum_to_bin(data->k, cruft, prime_len, prime_len);
753 eap_pwd_h_update(hash, cruft, prime_len);
755 /* server element: x, y */
756 if (crypto_ec_point_to_bin(data->grp->group, data->server_element,
757 cruft, cruft + prime_len) != 0) {
758 wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
762 eap_pwd_h_update(hash, cruft, prime_len * 2);
765 crypto_bignum_to_bin(data->server_scalar, cruft, order_len, order_len);
766 eap_pwd_h_update(hash, cruft, order_len);
768 /* my element: x, y */
769 if (crypto_ec_point_to_bin(data->grp->group, data->my_element, cruft,
770 cruft + prime_len) != 0) {
771 wpa_printf(MSG_INFO, "EAP-PWD (server): confirm point "
775 eap_pwd_h_update(hash, cruft, prime_len * 2);
778 crypto_bignum_to_bin(data->my_scalar, cruft, order_len, order_len);
779 eap_pwd_h_update(hash, cruft, order_len);
781 /* the ciphersuite */
782 eap_pwd_h_update(hash, (u8 *) &cs, sizeof(u32));
784 /* random function fin */
785 eap_pwd_h_final(hash, conf);
788 ptr = (u8 *) payload;
789 if (os_memcmp_const(conf, ptr, SHA256_MAC_LEN)) {
790 wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm did not verify");
794 wpa_printf(MSG_DEBUG, "EAP-pwd (peer): confirm verified");
798 * H(k | peer_element | peer_scalar | server_element | server_scalar |
801 hash = eap_pwd_h_init();
806 crypto_bignum_to_bin(data->k, cruft, prime_len, prime_len);
807 eap_pwd_h_update(hash, cruft, prime_len);
810 if (crypto_ec_point_to_bin(data->grp->group, data->my_element, cruft,
811 cruft + prime_len) != 0) {
812 wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
816 eap_pwd_h_update(hash, cruft, prime_len * 2);
819 crypto_bignum_to_bin(data->my_scalar, cruft, order_len, order_len);
820 eap_pwd_h_update(hash, cruft, order_len);
822 /* server element: x, y */
823 if (crypto_ec_point_to_bin(data->grp->group, data->server_element,
824 cruft, cruft + prime_len) != 0) {
825 wpa_printf(MSG_INFO, "EAP-PWD (peer): confirm point "
829 eap_pwd_h_update(hash, cruft, prime_len * 2);
832 crypto_bignum_to_bin(data->server_scalar, cruft, order_len, order_len);
833 eap_pwd_h_update(hash, cruft, order_len);
835 /* the ciphersuite */
836 eap_pwd_h_update(hash, (u8 *) &cs, sizeof(u32));
839 eap_pwd_h_final(hash, conf);
842 if (compute_keys(data->grp, data->k,
843 data->my_scalar, data->server_scalar, conf, ptr,
844 &cs, data->msk, data->emsk, data->session_id) < 0) {
845 wpa_printf(MSG_INFO, "EAP-PWD (peer): unable to compute MSK | "
850 data->outbuf = wpabuf_alloc(SHA256_MAC_LEN);
851 if (data->outbuf == NULL)
854 wpabuf_put_data(data->outbuf, conf, SHA256_MAC_LEN);
857 bin_clear_free(cruft, prime_len * 2);
858 if (data->outbuf == NULL) {
859 ret->methodState = METHOD_DONE;
860 ret->decision = DECISION_FAIL;
861 eap_pwd_state(data, FAILURE);
863 eap_pwd_state(data, SUCCESS_ON_FRAG_COMPLETION);
866 /* clean allocated memory */
868 eap_pwd_h_final(hash, conf);
872 static struct wpabuf *
873 eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
874 const struct wpabuf *reqData)
876 struct eap_pwd_data *data = priv;
877 struct wpabuf *resp = NULL;
883 pos = eap_hdr_validate(EAP_VENDOR_IETF, EAP_TYPE_PWD, reqData, &len);
884 if ((pos == NULL) || (len < 1)) {
885 wpa_printf(MSG_DEBUG, "EAP-pwd: Got a frame but pos is %s and "
887 pos == NULL ? "NULL" : "not NULL", (int) len);
893 ret->methodState = METHOD_MAY_CONT;
894 ret->decision = DECISION_FAIL;
895 ret->allowNotifications = FALSE;
898 pos++; /* skip over the bits and the exch */
902 * we're fragmenting so send out the next fragment
904 if (data->out_frag_pos) {
906 * this should be an ACK
909 wpa_printf(MSG_INFO, "Bad Response! Fragmenting but "
912 wpa_printf(MSG_DEBUG, "EAP-pwd: Got an ACK for a fragment");
914 * check if there are going to be more fragments
916 len = wpabuf_len(data->outbuf) - data->out_frag_pos;
917 if ((len + EAP_PWD_HDR_SIZE) > data->mtu) {
918 len = data->mtu - EAP_PWD_HDR_SIZE;
919 EAP_PWD_SET_MORE_BIT(lm_exch);
921 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
922 EAP_PWD_HDR_SIZE + len,
923 EAP_CODE_RESPONSE, eap_get_id(reqData));
925 wpa_printf(MSG_INFO, "Unable to allocate memory for "
929 wpabuf_put_u8(resp, lm_exch);
930 buf = wpabuf_head_u8(data->outbuf);
931 wpabuf_put_data(resp, buf + data->out_frag_pos, len);
932 data->out_frag_pos += len;
934 * this is the last fragment so get rid of the out buffer
936 if (data->out_frag_pos >= wpabuf_len(data->outbuf)) {
937 wpabuf_free(data->outbuf);
939 data->out_frag_pos = 0;
941 wpa_printf(MSG_DEBUG, "EAP-pwd: Send %s fragment of %d bytes",
942 data->out_frag_pos == 0 ? "last" : "next",
944 if (data->state == SUCCESS_ON_FRAG_COMPLETION) {
945 ret->methodState = METHOD_DONE;
946 ret->decision = DECISION_UNCOND_SUCC;
947 eap_pwd_state(data, SUCCESS);
953 * see if this is a fragment that needs buffering
955 * if it's the first fragment there'll be a length field
957 if (EAP_PWD_GET_LENGTH_BIT(lm_exch)) {
959 wpa_printf(MSG_DEBUG,
960 "EAP-pwd: Frame too short to contain Total-Length field");
964 tot_len = WPA_GET_BE16(pos);
965 wpa_printf(MSG_DEBUG, "EAP-pwd: Incoming fragments whose "
966 "total length = %d", tot_len);
970 wpa_printf(MSG_DEBUG,
971 "EAP-pwd: Unexpected new fragment start when previous fragment is still in use");
975 data->inbuf = wpabuf_alloc(tot_len);
976 if (data->inbuf == NULL) {
977 wpa_printf(MSG_INFO, "Out of memory to buffer "
981 data->in_frag_pos = 0;
986 * buffer and ACK the fragment
988 if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {
989 data->in_frag_pos += len;
990 if (data->in_frag_pos > wpabuf_size(data->inbuf)) {
991 wpa_printf(MSG_INFO, "EAP-pwd: Buffer overflow attack "
992 "detected (%d vs. %d)!",
993 (int) data->in_frag_pos,
994 (int) wpabuf_len(data->inbuf));
995 wpabuf_free(data->inbuf);
997 data->in_frag_pos = 0;
1000 wpabuf_put_data(data->inbuf, pos, len);
1002 if (EAP_PWD_GET_MORE_BIT(lm_exch)) {
1003 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
1005 EAP_CODE_RESPONSE, eap_get_id(reqData));
1007 wpabuf_put_u8(resp, (EAP_PWD_GET_EXCHANGE(lm_exch)));
1008 wpa_printf(MSG_DEBUG, "EAP-pwd: ACKing a %d byte fragment",
1013 * we're buffering and this is the last fragment
1015 if (data->in_frag_pos) {
1016 wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",
1018 pos = wpabuf_head_u8(data->inbuf);
1019 len = data->in_frag_pos;
1021 wpa_printf(MSG_DEBUG, "EAP-pwd: processing frame: exch %d, len %d",
1022 EAP_PWD_GET_EXCHANGE(lm_exch), (int) len);
1024 switch (EAP_PWD_GET_EXCHANGE(lm_exch)) {
1025 case EAP_PWD_OPCODE_ID_EXCH:
1026 eap_pwd_perform_id_exchange(sm, data, ret, reqData,
1029 case EAP_PWD_OPCODE_COMMIT_EXCH:
1030 eap_pwd_perform_commit_exchange(sm, data, ret, reqData,
1033 case EAP_PWD_OPCODE_CONFIRM_EXCH:
1034 eap_pwd_perform_confirm_exchange(sm, data, ret, reqData,
1038 wpa_printf(MSG_INFO, "EAP-pwd: Ignoring message with unknown "
1039 "opcode %d", lm_exch);
1043 * if we buffered the just processed input now's the time to free it
1045 if (data->in_frag_pos) {
1046 wpabuf_free(data->inbuf);
1048 data->in_frag_pos = 0;
1051 if (data->outbuf == NULL) {
1052 ret->methodState = METHOD_DONE;
1053 ret->decision = DECISION_FAIL;
1054 return NULL; /* generic failure */
1058 * we have output! Do we need to fragment it?
1060 lm_exch = EAP_PWD_GET_EXCHANGE(lm_exch);
1061 len = wpabuf_len(data->outbuf);
1062 if ((len + EAP_PWD_HDR_SIZE) > data->mtu) {
1063 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD, data->mtu,
1064 EAP_CODE_RESPONSE, eap_get_id(reqData));
1066 * if so it's the first so include a length field
1068 EAP_PWD_SET_LENGTH_BIT(lm_exch);
1069 EAP_PWD_SET_MORE_BIT(lm_exch);
1072 * keep the packet at the MTU
1074 len = data->mtu - EAP_PWD_HDR_SIZE - sizeof(u16);
1075 wpa_printf(MSG_DEBUG, "EAP-pwd: Fragmenting output, total "
1076 "length = %d", tot_len);
1078 resp = eap_msg_alloc(EAP_VENDOR_IETF, EAP_TYPE_PWD,
1079 EAP_PWD_HDR_SIZE + len,
1080 EAP_CODE_RESPONSE, eap_get_id(reqData));
1085 wpabuf_put_u8(resp, lm_exch);
1086 if (EAP_PWD_GET_LENGTH_BIT(lm_exch)) {
1087 wpabuf_put_be16(resp, tot_len);
1088 data->out_frag_pos += len;
1090 buf = wpabuf_head_u8(data->outbuf);
1091 wpabuf_put_data(resp, buf, len);
1093 * if we're not fragmenting then there's no need to carry this around
1095 if (data->out_frag_pos == 0) {
1096 wpabuf_free(data->outbuf);
1097 data->outbuf = NULL;
1098 data->out_frag_pos = 0;
1099 if (data->state == SUCCESS_ON_FRAG_COMPLETION) {
1100 ret->methodState = METHOD_DONE;
1101 ret->decision = DECISION_UNCOND_SUCC;
1102 eap_pwd_state(data, SUCCESS);
1110 static Boolean eap_pwd_key_available(struct eap_sm *sm, void *priv)
1112 struct eap_pwd_data *data = priv;
1113 return data->state == SUCCESS;
1117 static u8 * eap_pwd_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1119 struct eap_pwd_data *data = priv;
1122 if (data->state != SUCCESS)
1125 if ((key = os_malloc(EAP_EMSK_LEN)) == NULL)
1128 os_memcpy(key, data->emsk, EAP_EMSK_LEN);
1129 *len = EAP_EMSK_LEN;
1135 int eap_peer_pwd_register(void)
1137 struct eap_method *eap;
1139 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
1140 EAP_VENDOR_IETF, EAP_TYPE_PWD, "PWD");
1144 eap->init = eap_pwd_init;
1145 eap->deinit = eap_pwd_deinit;
1146 eap->process = eap_pwd_process;
1147 eap->isKeyAvailable = eap_pwd_key_available;
1148 eap->getKey = eap_pwd_getkey;
1149 eap->getSessionId = eap_pwd_get_session_id;
1150 eap->get_emsk = eap_pwd_get_emsk;
1152 return eap_peer_method_register(eap);