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Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -08001/*
2 * WPA Supplicant - Mesh RSN routines
3 * Copyright (c) 2013-2014, cozybit, Inc. All rights reserved.
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "utils/includes.h"
10
11#include "utils/common.h"
12#include "utils/eloop.h"
13#include "crypto/sha256.h"
14#include "crypto/random.h"
15#include "crypto/aes.h"
16#include "crypto/aes_siv.h"
17#include "rsn_supp/wpa.h"
18#include "ap/hostapd.h"
19#include "ap/wpa_auth.h"
20#include "ap/sta_info.h"
Dmitry Shmidtff787d52015-01-12 13:01:47 -080021#include "ap/ieee802_11.h"
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080022#include "wpa_supplicant_i.h"
23#include "driver_i.h"
24#include "wpas_glue.h"
25#include "mesh_mpm.h"
26#include "mesh_rsn.h"
27
28#define MESH_AUTH_TIMEOUT 10
29#define MESH_AUTH_RETRY 3
30
31void mesh_auth_timer(void *eloop_ctx, void *user_data)
32{
33 struct wpa_supplicant *wpa_s = eloop_ctx;
34 struct sta_info *sta = user_data;
Dmitry Shmidte4663042016-04-04 10:07:49 -070035 struct hostapd_data *hapd;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080036
37 if (sta->sae->state != SAE_ACCEPTED) {
38 wpa_printf(MSG_DEBUG, "AUTH: Re-authenticate with " MACSTR
39 " (attempt %d) ",
40 MAC2STR(sta->addr), sta->sae_auth_retry);
Dmitry Shmidt7f656022015-02-25 14:36:37 -080041 wpa_msg(wpa_s, MSG_INFO, MESH_SAE_AUTH_FAILURE "addr=" MACSTR,
42 MAC2STR(sta->addr));
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080043 if (sta->sae_auth_retry < MESH_AUTH_RETRY) {
44 mesh_rsn_auth_sae_sta(wpa_s, sta);
45 } else {
Dmitry Shmidte4663042016-04-04 10:07:49 -070046 hapd = wpa_s->ifmsh->bss[0];
47
Dmitry Shmidt7f656022015-02-25 14:36:37 -080048 if (sta->sae_auth_retry > MESH_AUTH_RETRY) {
Dmitry Shmidte4663042016-04-04 10:07:49 -070049 ap_free_sta(hapd, sta);
Dmitry Shmidt7f656022015-02-25 14:36:37 -080050 return;
51 }
52
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080053 /* block the STA if exceeded the number of attempts */
Dmitry Shmidt216983b2015-02-06 10:50:36 -080054 wpa_mesh_set_plink_state(wpa_s, sta, PLINK_BLOCKED);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080055 sta->sae->state = SAE_NOTHING;
Dmitry Shmidt7f656022015-02-25 14:36:37 -080056 wpa_msg(wpa_s, MSG_INFO, MESH_SAE_AUTH_BLOCKED "addr="
57 MACSTR " duration=%d",
58 MAC2STR(sta->addr),
Dmitry Shmidte4663042016-04-04 10:07:49 -070059 hapd->conf->ap_max_inactivity);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080060 }
61 sta->sae_auth_retry++;
62 }
63}
64
65
66static void auth_logger(void *ctx, const u8 *addr, logger_level level,
67 const char *txt)
68{
69 if (addr)
70 wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
71 MAC2STR(addr), txt);
72 else
73 wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
74}
75
76
77static const u8 *auth_get_psk(void *ctx, const u8 *addr,
Dmitry Shmidtd2986c22017-10-23 14:22:09 -070078 const u8 *p2p_dev_addr, const u8 *prev_psk,
79 size_t *psk_len)
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080080{
81 struct mesh_rsn *mesh_rsn = ctx;
82 struct hostapd_data *hapd = mesh_rsn->wpa_s->ifmsh->bss[0];
83 struct sta_info *sta = ap_get_sta(hapd, addr);
84
Dmitry Shmidtd2986c22017-10-23 14:22:09 -070085 if (psk_len)
86 *psk_len = PMK_LEN;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -080087 wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
88 __func__, MAC2STR(addr), prev_psk);
89
90 if (sta && sta->auth_alg == WLAN_AUTH_SAE) {
91 if (!sta->sae || prev_psk)
92 return NULL;
93 return sta->sae->pmk;
94 }
95
96 return NULL;
97}
98
99
100static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
101 const u8 *addr, int idx, u8 *key, size_t key_len)
102{
103 struct mesh_rsn *mesh_rsn = ctx;
104 u8 seq[6];
105
106 os_memset(seq, 0, sizeof(seq));
107
108 if (addr) {
109 wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
110 " key_idx=%d)",
111 __func__, alg, MAC2STR(addr), idx);
112 } else {
113 wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
114 __func__, alg, idx);
115 }
116 wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
117
118 return wpa_drv_set_key(mesh_rsn->wpa_s, alg, addr, idx,
119 1, seq, 6, key, key_len);
120}
121
122
123static int auth_start_ampe(void *ctx, const u8 *addr)
124{
125 struct mesh_rsn *mesh_rsn = ctx;
126 struct hostapd_data *hapd;
127 struct sta_info *sta;
128
129 if (mesh_rsn->wpa_s->current_ssid->mode != WPAS_MODE_MESH)
130 return -1;
131
132 hapd = mesh_rsn->wpa_s->ifmsh->bss[0];
133 sta = ap_get_sta(hapd, addr);
134 if (sta)
135 eloop_cancel_timeout(mesh_auth_timer, mesh_rsn->wpa_s, sta);
136
137 mesh_mpm_auth_peer(mesh_rsn->wpa_s, addr);
138 return 0;
139}
140
141
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700142static int __mesh_rsn_auth_init(struct mesh_rsn *rsn, const u8 *addr,
Hai Shalom74f70d42019-02-11 14:42:39 -0800143 enum mfp_options ieee80211w, int ocv)
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800144{
145 struct wpa_auth_config conf;
Paul Stewart092955c2017-02-06 09:13:09 -0800146 static const struct wpa_auth_callbacks cb = {
147 .logger = auth_logger,
148 .get_psk = auth_get_psk,
149 .set_key = auth_set_key,
150 .start_ampe = auth_start_ampe,
151 };
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800152 u8 seq[6] = {};
153
154 wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
155
156 os_memset(&conf, 0, sizeof(conf));
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700157 conf.wpa = WPA_PROTO_RSN;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800158 conf.wpa_key_mgmt = WPA_KEY_MGMT_SAE;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700159 conf.wpa_pairwise = rsn->pairwise_cipher;
160 conf.rsn_pairwise = rsn->pairwise_cipher;
161 conf.wpa_group = rsn->group_cipher;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800162 conf.eapol_version = 0;
163 conf.wpa_group_rekey = -1;
Dmitry Shmidtebd93af2017-02-21 13:40:44 -0800164 conf.wpa_group_update_count = 4;
165 conf.wpa_pairwise_update_count = 4;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700166#ifdef CONFIG_IEEE80211W
167 conf.ieee80211w = ieee80211w;
168 if (ieee80211w != NO_MGMT_FRAME_PROTECTION)
169 conf.group_mgmt_cipher = rsn->mgmt_group_cipher;
170#endif /* CONFIG_IEEE80211W */
Hai Shalom74f70d42019-02-11 14:42:39 -0800171#ifdef CONFIG_OCV
172 conf.ocv = ocv;
173#endif /* CONFIG_OCV */
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800174
Paul Stewart092955c2017-02-06 09:13:09 -0800175 rsn->auth = wpa_init(addr, &conf, &cb, rsn);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800176 if (rsn->auth == NULL) {
177 wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
178 return -1;
179 }
180
181 /* TODO: support rekeying */
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700182 rsn->mgtk_len = wpa_cipher_key_len(conf.wpa_group);
183 if (random_get_bytes(rsn->mgtk, rsn->mgtk_len) < 0)
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800184 return -1;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700185 rsn->mgtk_key_id = 1;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800186
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700187#ifdef CONFIG_IEEE80211W
188 if (ieee80211w != NO_MGMT_FRAME_PROTECTION) {
189 rsn->igtk_len = wpa_cipher_key_len(conf.group_mgmt_cipher);
190 if (random_get_bytes(rsn->igtk, rsn->igtk_len) < 0)
191 return -1;
192 rsn->igtk_key_id = 4;
193
194 /* group mgmt */
195 wpa_hexdump_key(MSG_DEBUG, "mesh: Own TX IGTK",
196 rsn->igtk, rsn->igtk_len);
197 wpa_drv_set_key(rsn->wpa_s,
198 wpa_cipher_to_alg(rsn->mgmt_group_cipher), NULL,
199 rsn->igtk_key_id, 1,
200 seq, sizeof(seq), rsn->igtk, rsn->igtk_len);
201 }
202#endif /* CONFIG_IEEE80211W */
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800203
204 /* group privacy / data frames */
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700205 wpa_hexdump_key(MSG_DEBUG, "mesh: Own TX MGTK",
206 rsn->mgtk, rsn->mgtk_len);
207 wpa_drv_set_key(rsn->wpa_s, wpa_cipher_to_alg(rsn->group_cipher), NULL,
208 rsn->mgtk_key_id, 1, seq, sizeof(seq),
209 rsn->mgtk, rsn->mgtk_len);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800210
211 return 0;
212}
213
214
215static void mesh_rsn_deinit(struct mesh_rsn *rsn)
216{
217 os_memset(rsn->mgtk, 0, sizeof(rsn->mgtk));
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700218 rsn->mgtk_len = 0;
219 os_memset(rsn->igtk, 0, sizeof(rsn->igtk));
220 rsn->igtk_len = 0;
Dmitry Shmidtd80a4012015-11-05 16:35:40 -0800221 if (rsn->auth)
222 wpa_deinit(rsn->auth);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800223}
224
225
226struct mesh_rsn *mesh_rsn_auth_init(struct wpa_supplicant *wpa_s,
227 struct mesh_conf *conf)
228{
229 struct mesh_rsn *mesh_rsn;
230 struct hostapd_data *bss = wpa_s->ifmsh->bss[0];
231 const u8 *ie;
232 size_t ie_len;
Paul Stewart092955c2017-02-06 09:13:09 -0800233#ifdef CONFIG_PMKSA_CACHE_EXTERNAL
234 struct external_pmksa_cache *entry;
235#endif /* CONFIG_PMKSA_CACHE_EXTERNAL */
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800236
237 mesh_rsn = os_zalloc(sizeof(*mesh_rsn));
238 if (mesh_rsn == NULL)
239 return NULL;
240 mesh_rsn->wpa_s = wpa_s;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700241 mesh_rsn->pairwise_cipher = conf->pairwise_cipher;
242 mesh_rsn->group_cipher = conf->group_cipher;
243 mesh_rsn->mgmt_group_cipher = conf->mgmt_group_cipher;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800244
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700245 if (__mesh_rsn_auth_init(mesh_rsn, wpa_s->own_addr,
Hai Shalom74f70d42019-02-11 14:42:39 -0800246 conf->ieee80211w, conf->ocv) < 0) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800247 mesh_rsn_deinit(mesh_rsn);
Dmitry Shmidtd80a4012015-11-05 16:35:40 -0800248 os_free(mesh_rsn);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800249 return NULL;
250 }
251
252 bss->wpa_auth = mesh_rsn->auth;
253
Paul Stewart092955c2017-02-06 09:13:09 -0800254#ifdef CONFIG_PMKSA_CACHE_EXTERNAL
255 while ((entry = dl_list_last(&wpa_s->mesh_external_pmksa_cache,
256 struct external_pmksa_cache,
257 list)) != NULL) {
258 int ret;
259
260 ret = wpa_auth_pmksa_add_entry(bss->wpa_auth,
261 entry->pmksa_cache);
262 dl_list_del(&entry->list);
263 os_free(entry);
264
265 if (ret < 0)
266 return NULL;
267 }
268#endif /* CONFIG_PMKSA_CACHE_EXTERNAL */
269
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800270 ie = wpa_auth_get_wpa_ie(mesh_rsn->auth, &ie_len);
Dmitry Shmidtd80a4012015-11-05 16:35:40 -0800271 conf->rsn_ie = (u8 *) ie;
272 conf->rsn_ie_len = ie_len;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800273
274 wpa_supplicant_rsn_supp_set_config(wpa_s, wpa_s->current_ssid);
275
276 return mesh_rsn;
277}
278
279
280static int index_within_array(const int *array, int idx)
281{
282 int i;
283
284 for (i = 0; i < idx; i++) {
285 if (array[i] == -1)
286 return 0;
287 }
288
289 return 1;
290}
291
292
293static int mesh_rsn_sae_group(struct wpa_supplicant *wpa_s,
294 struct sae_data *sae)
295{
296 int *groups = wpa_s->ifmsh->bss[0]->conf->sae_groups;
297
298 /* Configuration may have changed, so validate current index */
299 if (!index_within_array(groups, wpa_s->mesh_rsn->sae_group_index))
300 return -1;
301
302 for (;;) {
303 int group = groups[wpa_s->mesh_rsn->sae_group_index];
304
305 if (group <= 0)
306 break;
307 if (sae_set_group(sae, group) == 0) {
308 wpa_dbg(wpa_s, MSG_DEBUG, "SME: Selected SAE group %d",
309 sae->group);
310 return 0;
311 }
312 wpa_s->mesh_rsn->sae_group_index++;
313 }
314
315 return -1;
316}
317
318
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800319static int mesh_rsn_build_sae_commit(struct wpa_supplicant *wpa_s,
320 struct wpa_ssid *ssid,
321 struct sta_info *sta)
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800322{
Dmitry Shmidtd2986c22017-10-23 14:22:09 -0700323 const char *password;
324
325 password = ssid->sae_password;
326 if (!password)
327 password = ssid->passphrase;
328 if (!password) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800329 wpa_msg(wpa_s, MSG_DEBUG, "SAE: No password available");
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800330 return -1;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800331 }
332
333 if (mesh_rsn_sae_group(wpa_s, sta->sae) < 0) {
334 wpa_msg(wpa_s, MSG_DEBUG, "SAE: Failed to select group");
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800335 return -1;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800336 }
337
Roshan Pius3a1667e2018-07-03 15:17:14 -0700338 if (sta->sae->tmp && !sta->sae->tmp->pw_id && ssid->sae_password_id) {
339 sta->sae->tmp->pw_id = os_strdup(ssid->sae_password_id);
340 if (!sta->sae->tmp->pw_id)
341 return -1;
342 }
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800343 return sae_prepare_commit(wpa_s->own_addr, sta->addr,
Dmitry Shmidtd2986c22017-10-23 14:22:09 -0700344 (u8 *) password, os_strlen(password),
Roshan Pius3a1667e2018-07-03 15:17:14 -0700345 ssid->sae_password_id,
Dmitry Shmidtd2986c22017-10-23 14:22:09 -0700346 sta->sae);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800347}
348
349
350/* initiate new SAE authentication with sta */
351int mesh_rsn_auth_sae_sta(struct wpa_supplicant *wpa_s,
352 struct sta_info *sta)
353{
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800354 struct hostapd_data *hapd = wpa_s->ifmsh->bss[0];
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800355 struct wpa_ssid *ssid = wpa_s->current_ssid;
Dmitry Shmidte4663042016-04-04 10:07:49 -0700356 struct rsn_pmksa_cache_entry *pmksa;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800357 unsigned int rnd;
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800358 int ret;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800359
360 if (!ssid) {
361 wpa_msg(wpa_s, MSG_DEBUG,
362 "AUTH: No current_ssid known to initiate new SAE");
363 return -1;
364 }
365
366 if (!sta->sae) {
367 sta->sae = os_zalloc(sizeof(*sta->sae));
368 if (sta->sae == NULL)
369 return -1;
370 }
371
Dmitry Shmidt9839ecd2016-11-07 11:05:47 -0800372 pmksa = wpa_auth_pmksa_get(hapd->wpa_auth, sta->addr, NULL);
Dmitry Shmidte4663042016-04-04 10:07:49 -0700373 if (pmksa) {
374 if (!sta->wpa_sm)
375 sta->wpa_sm = wpa_auth_sta_init(hapd->wpa_auth,
376 sta->addr, NULL);
377 if (!sta->wpa_sm) {
378 wpa_printf(MSG_ERROR,
379 "mesh: Failed to initialize RSN state machine");
380 return -1;
381 }
382
383 wpa_printf(MSG_DEBUG,
384 "AUTH: Mesh PMKSA cache entry found for " MACSTR
385 " - try to use PMKSA caching instead of new SAE authentication",
386 MAC2STR(sta->addr));
387 wpa_auth_pmksa_set_to_sm(pmksa, sta->wpa_sm, hapd->wpa_auth,
388 sta->sae->pmkid, sta->sae->pmk);
389 sae_accept_sta(hapd, sta);
390 sta->mesh_sae_pmksa_caching = 1;
391 return 0;
392 }
393 sta->mesh_sae_pmksa_caching = 0;
394
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800395 if (mesh_rsn_build_sae_commit(wpa_s, ssid, sta))
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800396 return -1;
397
398 wpa_msg(wpa_s, MSG_DEBUG,
399 "AUTH: started authentication with SAE peer: " MACSTR,
400 MAC2STR(sta->addr));
401
Dmitry Shmidtff787d52015-01-12 13:01:47 -0800402 ret = auth_sae_init_committed(hapd, sta);
403 if (ret)
404 return ret;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800405
Dmitry Shmidt7f656022015-02-25 14:36:37 -0800406 eloop_cancel_timeout(mesh_auth_timer, wpa_s, sta);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800407 rnd = rand() % MESH_AUTH_TIMEOUT;
408 eloop_register_timeout(MESH_AUTH_TIMEOUT + rnd, 0, mesh_auth_timer,
409 wpa_s, sta);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800410 return 0;
411}
412
413
414void mesh_rsn_get_pmkid(struct mesh_rsn *rsn, struct sta_info *sta, u8 *pmkid)
415{
Dmitry Shmidtd97138d2015-12-28 13:27:49 -0800416 os_memcpy(pmkid, sta->sae->pmkid, SAE_PMKID_LEN);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800417}
418
419
420static void
421mesh_rsn_derive_aek(struct mesh_rsn *rsn, struct sta_info *sta)
422{
423 u8 *myaddr = rsn->wpa_s->own_addr;
424 u8 *peer = sta->addr;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700425 u8 *addr1, *addr2;
426 u8 context[RSN_SELECTOR_LEN + 2 * ETH_ALEN], *ptr = context;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800427
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700428 /*
429 * AEK = KDF-Hash-256(PMK, "AEK Derivation", Selected AKM Suite ||
430 * min(localMAC, peerMAC) || max(localMAC, peerMAC))
431 */
432 /* Selected AKM Suite: SAE */
433 RSN_SELECTOR_PUT(ptr, RSN_AUTH_KEY_MGMT_SAE);
434 ptr += RSN_SELECTOR_LEN;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800435
436 if (os_memcmp(myaddr, peer, ETH_ALEN) < 0) {
437 addr1 = myaddr;
438 addr2 = peer;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700439 } else {
440 addr1 = peer;
441 addr2 = myaddr;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800442 }
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700443 os_memcpy(ptr, addr1, ETH_ALEN);
444 ptr += ETH_ALEN;
445 os_memcpy(ptr, addr2, ETH_ALEN);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800446
447 sha256_prf(sta->sae->pmk, sizeof(sta->sae->pmk), "AEK Derivation",
448 context, sizeof(context), sta->aek, sizeof(sta->aek));
449}
450
451
452/* derive mesh temporal key from pmk */
453int mesh_rsn_derive_mtk(struct wpa_supplicant *wpa_s, struct sta_info *sta)
454{
455 u8 *ptr;
456 u8 *min, *max;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800457 u8 *myaddr = wpa_s->own_addr;
458 u8 *peer = sta->addr;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700459 u8 context[2 * WPA_NONCE_LEN + 2 * 2 + RSN_SELECTOR_LEN + 2 * ETH_ALEN];
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800460
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700461 /*
462 * MTK = KDF-Hash-Length(PMK, "Temporal Key Derivation", min(localNonce,
463 * peerNonce) || max(localNonce, peerNonce) || min(localLinkID,
464 * peerLinkID) || max(localLinkID, peerLinkID) || Selected AKM Suite ||
465 * min(localMAC, peerMAC) || max(localMAC, peerMAC))
466 */
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800467 ptr = context;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700468 if (os_memcmp(sta->my_nonce, sta->peer_nonce, WPA_NONCE_LEN) < 0) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800469 min = sta->my_nonce;
470 max = sta->peer_nonce;
471 } else {
472 min = sta->peer_nonce;
473 max = sta->my_nonce;
474 }
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700475 os_memcpy(ptr, min, WPA_NONCE_LEN);
476 ptr += WPA_NONCE_LEN;
477 os_memcpy(ptr, max, WPA_NONCE_LEN);
478 ptr += WPA_NONCE_LEN;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800479
480 if (sta->my_lid < sta->peer_lid) {
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700481 WPA_PUT_LE16(ptr, sta->my_lid);
482 ptr += 2;
483 WPA_PUT_LE16(ptr, sta->peer_lid);
484 ptr += 2;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800485 } else {
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700486 WPA_PUT_LE16(ptr, sta->peer_lid);
487 ptr += 2;
488 WPA_PUT_LE16(ptr, sta->my_lid);
489 ptr += 2;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800490 }
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800491
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700492 /* Selected AKM Suite: SAE */
493 RSN_SELECTOR_PUT(ptr, RSN_AUTH_KEY_MGMT_SAE);
494 ptr += RSN_SELECTOR_LEN;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800495
496 if (os_memcmp(myaddr, peer, ETH_ALEN) < 0) {
497 min = myaddr;
498 max = peer;
499 } else {
500 min = peer;
501 max = myaddr;
502 }
503 os_memcpy(ptr, min, ETH_ALEN);
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700504 ptr += ETH_ALEN;
505 os_memcpy(ptr, max, ETH_ALEN);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800506
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700507 sta->mtk_len = wpa_cipher_key_len(wpa_s->mesh_rsn->pairwise_cipher);
508 sha256_prf(sta->sae->pmk, SAE_PMK_LEN,
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800509 "Temporal Key Derivation", context, sizeof(context),
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700510 sta->mtk, sta->mtk_len);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800511 return 0;
512}
513
514
515void mesh_rsn_init_ampe_sta(struct wpa_supplicant *wpa_s, struct sta_info *sta)
516{
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700517 if (random_get_bytes(sta->my_nonce, WPA_NONCE_LEN) < 0) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800518 wpa_printf(MSG_INFO, "mesh: Failed to derive random nonce");
519 /* TODO: How to handle this more cleanly? */
520 }
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700521 os_memset(sta->peer_nonce, 0, WPA_NONCE_LEN);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800522 mesh_rsn_derive_aek(wpa_s->mesh_rsn, sta);
523}
524
525
526/* insert AMPE and encrypted MIC at @ie.
527 * @mesh_rsn: mesh RSN context
528 * @sta: STA we're sending to
529 * @cat: pointer to category code in frame header.
530 * @buf: wpabuf to add encrypted AMPE and MIC to.
531 * */
532int mesh_rsn_protect_frame(struct mesh_rsn *rsn, struct sta_info *sta,
533 const u8 *cat, struct wpabuf *buf)
534{
535 struct ieee80211_ampe_ie *ampe;
536 u8 const *ie = wpabuf_head_u8(buf) + wpabuf_len(buf);
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700537 u8 *ampe_ie, *pos, *mic_payload;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800538 const u8 *aad[] = { rsn->wpa_s->own_addr, sta->addr, cat };
539 const size_t aad_len[] = { ETH_ALEN, ETH_ALEN, ie - cat };
540 int ret = 0;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700541 size_t len;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800542
Dmitry Shmidt58d12ad2016-07-28 10:07:03 -0700543 len = sizeof(*ampe);
544 if (cat[1] == PLINK_OPEN)
545 len += rsn->mgtk_len + WPA_KEY_RSC_LEN + 4;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700546#ifdef CONFIG_IEEE80211W
Dmitry Shmidt58d12ad2016-07-28 10:07:03 -0700547 if (cat[1] == PLINK_OPEN && rsn->igtk_len)
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700548 len += 2 + 6 + rsn->igtk_len;
549#endif /* CONFIG_IEEE80211W */
550
551 if (2 + AES_BLOCK_SIZE + 2 + len > wpabuf_tailroom(buf)) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800552 wpa_printf(MSG_ERROR, "protect frame: buffer too small");
553 return -EINVAL;
554 }
555
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700556 ampe_ie = os_zalloc(2 + len);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800557 if (!ampe_ie) {
558 wpa_printf(MSG_ERROR, "protect frame: out of memory");
559 return -ENOMEM;
560 }
561
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800562 /* IE: AMPE */
563 ampe_ie[0] = WLAN_EID_AMPE;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700564 ampe_ie[1] = len;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800565 ampe = (struct ieee80211_ampe_ie *) (ampe_ie + 2);
566
567 RSN_SELECTOR_PUT(ampe->selected_pairwise_suite,
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700568 RSN_CIPHER_SUITE_CCMP);
569 os_memcpy(ampe->local_nonce, sta->my_nonce, WPA_NONCE_LEN);
570 os_memcpy(ampe->peer_nonce, sta->peer_nonce, WPA_NONCE_LEN);
571
572 pos = (u8 *) (ampe + 1);
Dmitry Shmidt58d12ad2016-07-28 10:07:03 -0700573 if (cat[1] != PLINK_OPEN)
574 goto skip_keys;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700575
576 /* TODO: Key Replay Counter[8] optionally for
577 * Mesh Group Key Inform/Acknowledge frames */
578
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800579 /* TODO: static mgtk for now since we don't support rekeying! */
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700580 /*
581 * GTKdata[variable]:
582 * MGTK[variable] || Key RSC[8] || GTKExpirationTime[4]
583 */
584 os_memcpy(pos, rsn->mgtk, rsn->mgtk_len);
585 pos += rsn->mgtk_len;
586 wpa_drv_get_seqnum(rsn->wpa_s, NULL, rsn->mgtk_key_id, pos);
587 pos += WPA_KEY_RSC_LEN;
588 /* Use fixed GTKExpirationTime for now */
589 WPA_PUT_LE32(pos, 0xffffffff);
590 pos += 4;
591
592#ifdef CONFIG_IEEE80211W
593 /*
594 * IGTKdata[variable]:
595 * Key ID[2], IPN[6], IGTK[variable]
596 */
597 if (rsn->igtk_len) {
598 WPA_PUT_LE16(pos, rsn->igtk_key_id);
599 pos += 2;
600 wpa_drv_get_seqnum(rsn->wpa_s, NULL, rsn->igtk_key_id, pos);
601 pos += 6;
602 os_memcpy(pos, rsn->igtk, rsn->igtk_len);
603 }
604#endif /* CONFIG_IEEE80211W */
605
Dmitry Shmidt58d12ad2016-07-28 10:07:03 -0700606skip_keys:
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700607 wpa_hexdump_key(MSG_DEBUG, "mesh: Plaintext AMPE element",
608 ampe_ie, 2 + len);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800609
610 /* IE: MIC */
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700611 wpabuf_put_u8(buf, WLAN_EID_MIC);
612 wpabuf_put_u8(buf, AES_BLOCK_SIZE);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800613 /* MIC field is output ciphertext */
614
615 /* encrypt after MIC */
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700616 mic_payload = wpabuf_put(buf, 2 + len + AES_BLOCK_SIZE);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800617
Dmitry Shmidt9839ecd2016-11-07 11:05:47 -0800618 if (aes_siv_encrypt(sta->aek, sizeof(sta->aek), ampe_ie, 2 + len, 3,
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800619 aad, aad_len, mic_payload)) {
620 wpa_printf(MSG_ERROR, "protect frame: failed to encrypt");
621 ret = -ENOMEM;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800622 }
623
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800624 os_free(ampe_ie);
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800625
626 return ret;
627}
628
629
630int mesh_rsn_process_ampe(struct wpa_supplicant *wpa_s, struct sta_info *sta,
631 struct ieee802_11_elems *elems, const u8 *cat,
Dmitry Shmidtd97138d2015-12-28 13:27:49 -0800632 const u8 *chosen_pmk,
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800633 const u8 *start, size_t elems_len)
634{
635 int ret = 0;
636 struct ieee80211_ampe_ie *ampe;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700637 u8 null_nonce[WPA_NONCE_LEN] = {};
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800638 u8 ampe_eid;
639 u8 ampe_ie_len;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700640 u8 *ampe_buf, *crypt = NULL, *pos, *end;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800641 size_t crypt_len;
642 const u8 *aad[] = { sta->addr, wpa_s->own_addr, cat };
643 const size_t aad_len[] = { ETH_ALEN, ETH_ALEN,
644 (elems->mic - 2) - cat };
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700645 size_t key_len;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800646
Dmitry Shmidte4663042016-04-04 10:07:49 -0700647 if (!sta->sae) {
648 struct hostapd_data *hapd = wpa_s->ifmsh->bss[0];
649
Dmitry Shmidt9839ecd2016-11-07 11:05:47 -0800650 if (!wpa_auth_pmksa_get(hapd->wpa_auth, sta->addr, NULL)) {
Dmitry Shmidte4663042016-04-04 10:07:49 -0700651 wpa_printf(MSG_INFO,
652 "Mesh RSN: SAE is not prepared yet");
653 return -1;
654 }
655 mesh_rsn_auth_sae_sta(wpa_s, sta);
656 }
657
Dmitry Shmidtd97138d2015-12-28 13:27:49 -0800658 if (chosen_pmk && os_memcmp(chosen_pmk, sta->sae->pmkid, PMKID_LEN)) {
659 wpa_msg(wpa_s, MSG_DEBUG,
660 "Mesh RSN: Invalid PMKID (Chosen PMK did not match calculated PMKID)");
661 return -1;
662 }
663
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800664 if (!elems->mic || elems->mic_len < AES_BLOCK_SIZE) {
665 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: missing mic ie");
666 return -1;
667 }
668
669 ampe_buf = (u8 *) elems->mic + elems->mic_len;
670 if ((int) elems_len < ampe_buf - start)
671 return -1;
672
673 crypt_len = elems_len - (elems->mic - start);
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700674 if (crypt_len < 2 + AES_BLOCK_SIZE) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800675 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: missing ampe ie");
676 return -1;
677 }
678
679 /* crypt is modified by siv_decrypt */
680 crypt = os_zalloc(crypt_len);
681 if (!crypt) {
682 wpa_printf(MSG_ERROR, "Mesh RSN: out of memory");
683 ret = -ENOMEM;
684 goto free;
685 }
686
687 os_memcpy(crypt, elems->mic, crypt_len);
688
Dmitry Shmidt9839ecd2016-11-07 11:05:47 -0800689 if (aes_siv_decrypt(sta->aek, sizeof(sta->aek), crypt, crypt_len, 3,
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800690 aad, aad_len, ampe_buf)) {
691 wpa_printf(MSG_ERROR, "Mesh RSN: frame verification failed!");
Dmitry Shmidt58d12ad2016-07-28 10:07:03 -0700692 ret = -2;
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800693 goto free;
694 }
695
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700696 crypt_len -= AES_BLOCK_SIZE;
697 wpa_hexdump_key(MSG_DEBUG, "mesh: Decrypted AMPE element",
698 ampe_buf, crypt_len);
699
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800700 ampe_eid = *ampe_buf++;
701 ampe_ie_len = *ampe_buf++;
702
703 if (ampe_eid != WLAN_EID_AMPE ||
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700704 (size_t) 2 + ampe_ie_len > crypt_len ||
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800705 ampe_ie_len < sizeof(struct ieee80211_ampe_ie)) {
706 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: invalid ampe ie");
707 ret = -1;
708 goto free;
709 }
710
711 ampe = (struct ieee80211_ampe_ie *) ampe_buf;
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700712 pos = (u8 *) (ampe + 1);
713 end = ampe_buf + ampe_ie_len;
714 if (os_memcmp(ampe->peer_nonce, null_nonce, WPA_NONCE_LEN) != 0 &&
715 os_memcmp(ampe->peer_nonce, sta->my_nonce, WPA_NONCE_LEN) != 0) {
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800716 wpa_msg(wpa_s, MSG_DEBUG, "Mesh RSN: invalid peer nonce");
717 ret = -1;
718 goto free;
719 }
720 os_memcpy(sta->peer_nonce, ampe->local_nonce,
721 sizeof(ampe->local_nonce));
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800722
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700723 /* TODO: Key Replay Counter[8] in Mesh Group Key Inform/Acknowledge
724 * frames */
725
726 /*
Dmitry Shmidt58d12ad2016-07-28 10:07:03 -0700727 * GTKdata shall not be included in Mesh Peering Confirm. While the
728 * standard does not state the same about IGTKdata, that same constraint
729 * needs to apply for it. It makes no sense to include the keys in Mesh
730 * Peering Close frames either, so while the standard does not seem to
731 * have a shall statement for these, they are described without
732 * mentioning GTKdata.
733 *
734 * An earlier implementation used to add GTKdata to both Mesh Peering
735 * Open and Mesh Peering Confirm frames, so ignore the possibly present
736 * GTKdata frame without rejecting the frame as a backwards
737 * compatibility mechanism.
738 */
739 if (cat[1] != PLINK_OPEN) {
740 if (end > pos) {
741 wpa_hexdump_key(MSG_DEBUG,
742 "mesh: Ignore unexpected GTKdata(etc.) fields in the end of AMPE element in Mesh Peering Confirm/Close",
743 pos, end - pos);
744 }
745 goto free;
746 }
747
748 /*
Dmitry Shmidtd5ab1b52016-06-21 12:38:41 -0700749 * GTKdata[variable]:
750 * MGTK[variable] || Key RSC[8] || GTKExpirationTime[4]
751 */
752 sta->mgtk_key_id = 1; /* FIX: Where to get Key ID? */
753 key_len = wpa_cipher_key_len(wpa_s->mesh_rsn->group_cipher);
754 if ((int) key_len + WPA_KEY_RSC_LEN + 4 > end - pos) {
755 wpa_dbg(wpa_s, MSG_DEBUG, "mesh: Truncated AMPE element");
756 ret = -1;
757 goto free;
758 }
759 sta->mgtk_len = key_len;
760 os_memcpy(sta->mgtk, pos, sta->mgtk_len);
761 wpa_hexdump_key(MSG_DEBUG, "mesh: GTKdata - MGTK",
762 sta->mgtk, sta->mgtk_len);
763 pos += sta->mgtk_len;
764 wpa_hexdump(MSG_DEBUG, "mesh: GTKdata - MGTK - Key RSC",
765 pos, WPA_KEY_RSC_LEN);
766 os_memcpy(sta->mgtk_rsc, pos, sizeof(sta->mgtk_rsc));
767 pos += WPA_KEY_RSC_LEN;
768 wpa_printf(MSG_DEBUG,
769 "mesh: GTKdata - MGTK - GTKExpirationTime: %u seconds",
770 WPA_GET_LE32(pos));
771 pos += 4;
772
773#ifdef CONFIG_IEEE80211W
774 /*
775 * IGTKdata[variable]:
776 * Key ID[2], IPN[6], IGTK[variable]
777 */
778 key_len = wpa_cipher_key_len(wpa_s->mesh_rsn->mgmt_group_cipher);
779 if (end - pos >= (int) (2 + 6 + key_len)) {
780 sta->igtk_key_id = WPA_GET_LE16(pos);
781 wpa_printf(MSG_DEBUG, "mesh: IGTKdata - Key ID %u",
782 sta->igtk_key_id);
783 pos += 2;
784 os_memcpy(sta->igtk_rsc, pos, sizeof(sta->igtk_rsc));
785 wpa_hexdump(MSG_DEBUG, "mesh: IGTKdata - IPN",
786 sta->igtk_rsc, sizeof(sta->igtk_rsc));
787 pos += 6;
788 os_memcpy(sta->igtk, pos, key_len);
789 sta->igtk_len = key_len;
790 wpa_hexdump_key(MSG_DEBUG, "mesh: IGTKdata - IGTK",
791 sta->igtk, sta->igtk_len);
792 }
793#endif /* CONFIG_IEEE80211W */
794
Dmitry Shmidt6c0da2b2015-01-05 13:08:17 -0800795free:
796 os_free(crypt);
797 return ret;
798}