1 /*
2  * wpa_supplicant - IBSS RSN
3  * Copyright (c) 2009-2013, Jouni Malinen <j@w1.fi>
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #include "includes.h"
10 
11 #include "common.h"
12 #include "common/wpa_ctrl.h"
13 #include "utils/eloop.h"
14 #include "l2_packet/l2_packet.h"
15 #include "rsn_supp/wpa.h"
16 #include "rsn_supp/wpa_ie.h"
17 #include "ap/wpa_auth.h"
18 #include "wpa_supplicant_i.h"
19 #include "driver_i.h"
20 #include "common/ieee802_11_defs.h"
21 #include "ibss_rsn.h"
22 
23 
24 static void ibss_rsn_auth_timeout(void *eloop_ctx, void *timeout_ctx);
25 
26 
ibss_rsn_get_peer(struct ibss_rsn * ibss_rsn,const u8 * addr)27 static struct ibss_rsn_peer * ibss_rsn_get_peer(struct ibss_rsn *ibss_rsn,
28                                                             const u8 *addr)
29 {
30           struct ibss_rsn_peer *peer;
31 
32           for (peer = ibss_rsn->peers; peer; peer = peer->next)
33                     if (ether_addr_equal(addr, peer->addr))
34                               break;
35           return peer;
36 }
37 
38 
ibss_rsn_free(struct ibss_rsn_peer * peer)39 static void ibss_rsn_free(struct ibss_rsn_peer *peer)
40 {
41           eloop_cancel_timeout(ibss_rsn_auth_timeout, peer, NULL);
42           wpa_auth_sta_deinit(peer->auth);
43           wpa_sm_deinit(peer->supp);
44           os_free(peer);
45 }
46 
47 
supp_set_state(void * ctx,enum wpa_states state)48 static void supp_set_state(void *ctx, enum wpa_states state)
49 {
50           struct ibss_rsn_peer *peer = ctx;
51           peer->supp_state = state;
52 }
53 
54 
supp_get_state(void * ctx)55 static enum wpa_states supp_get_state(void *ctx)
56 {
57           struct ibss_rsn_peer *peer = ctx;
58           return peer->supp_state;
59 }
60 
61 
supp_ether_send(void * ctx,const u8 * dest,u16 proto,const u8 * buf,size_t len)62 static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
63                                  size_t len)
64 {
65           struct ibss_rsn_peer *peer = ctx;
66           struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
67           int encrypt = peer->authentication_status & IBSS_RSN_REPORTED_PTK;
68 
69           wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR
70                        " proto=0x%04x len=%lu no_encrypt=%d)",
71                        __func__, MAC2STR(dest), proto, (unsigned long) len,
72                        !encrypt);
73 
74           if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_CONTROL_PORT)
75                     return wpa_drv_tx_control_port(wpa_s, dest, proto, buf, len,
76                                                          !encrypt);
77 
78           if (wpa_s->l2)
79                     return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
80 
81           return -1;
82 }
83 
84 
supp_alloc_eapol(void * ctx,u8 type,const void * data,u16 data_len,size_t * msg_len,void ** data_pos)85 static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
86                                    u16 data_len, size_t *msg_len, void **data_pos)
87 {
88           struct ieee802_1x_hdr *hdr;
89 
90           wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
91                        __func__, type, data_len);
92 
93           *msg_len = sizeof(*hdr) + data_len;
94           hdr = os_malloc(*msg_len);
95           if (hdr == NULL)
96                     return NULL;
97 
98           hdr->version = 2;
99           hdr->type = type;
100           hdr->length = host_to_be16(data_len);
101 
102           if (data)
103                     os_memcpy(hdr + 1, data, data_len);
104           else
105                     os_memset(hdr + 1, 0, data_len);
106 
107           if (data_pos)
108                     *data_pos = hdr + 1;
109 
110           return (u8 *) hdr;
111 }
112 
113 
supp_get_beacon_ie(void * ctx)114 static int supp_get_beacon_ie(void *ctx)
115 {
116           struct ibss_rsn_peer *peer = ctx;
117 
118           wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
119           /* TODO: get correct RSN IE */
120           wpa_sm_set_ap_rsnxe(peer->supp, NULL, 0);
121           return wpa_sm_set_ap_rsn_ie(peer->supp,
122                                             (u8 *) "\x30\x14\x01\x00"
123                                             "\x00\x0f\xac\x04"
124                                             "\x01\x00\x00\x0f\xac\x04"
125                                             "\x01\x00\x00\x0f\xac\x02"
126                                             "\x00\x00", 22);
127 }
128 
129 
ibss_check_rsn_completed(struct ibss_rsn_peer * peer)130 static void ibss_check_rsn_completed(struct ibss_rsn_peer *peer)
131 {
132           struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
133 
134           if ((peer->authentication_status &
135                (IBSS_RSN_SET_PTK_SUPP | IBSS_RSN_SET_PTK_AUTH)) !=
136               (IBSS_RSN_SET_PTK_SUPP | IBSS_RSN_SET_PTK_AUTH))
137                     return;
138           if (peer->authentication_status & IBSS_RSN_REPORTED_PTK)
139                     return;
140           peer->authentication_status |= IBSS_RSN_REPORTED_PTK;
141           wpa_msg(wpa_s, MSG_INFO, IBSS_RSN_COMPLETED MACSTR,
142                     MAC2STR(peer->addr));
143 }
144 
145 
supp_set_key(void * ctx,int link_id,enum wpa_alg alg,const u8 * addr,int key_idx,int set_tx,const u8 * seq,size_t seq_len,const u8 * key,size_t key_len,enum key_flag key_flag)146 static int supp_set_key(void *ctx, int link_id, enum wpa_alg alg,
147                               const u8 *addr, int key_idx, int set_tx,
148                               const u8 *seq, size_t seq_len,
149                               const u8 *key, size_t key_len, enum key_flag key_flag)
150 {
151           struct ibss_rsn_peer *peer = ctx;
152 
153           wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
154                        "set_tx=%d)",
155                        __func__, alg, MAC2STR(addr), key_idx, set_tx);
156           wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
157           wpa_hexdump_key(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
158 
159           if (key_idx == 0) {
160                     peer->authentication_status |= IBSS_RSN_SET_PTK_SUPP;
161                     ibss_check_rsn_completed(peer);
162                     /*
163                      * In IBSS RSN, the pairwise key from the 4-way handshake
164                      * initiated by the peer with highest MAC address is used.
165                      */
166                     if (os_memcmp(peer->ibss_rsn->wpa_s->own_addr, peer->addr,
167                                     ETH_ALEN) > 0) {
168                               wpa_printf(MSG_DEBUG, "SUPP: Do not use this PTK");
169                               return 0;
170                     }
171           }
172 
173           if (is_broadcast_ether_addr(addr))
174                     addr = peer->addr;
175           return wpa_drv_set_key(peer->ibss_rsn->wpa_s, link_id, alg, addr,
176                                      key_idx, set_tx, seq, seq_len, key, key_len,
177                                      key_flag);
178 }
179 
180 
supp_get_network_ctx(void * ctx)181 static void * supp_get_network_ctx(void *ctx)
182 {
183           struct ibss_rsn_peer *peer = ctx;
184           return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
185 }
186 
187 
supp_mlme_setprotection(void * ctx,const u8 * addr,int protection_type,int key_type)188 static int supp_mlme_setprotection(void *ctx, const u8 *addr,
189                                            int protection_type, int key_type)
190 {
191           wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
192                        "key_type=%d)",
193                        __func__, MAC2STR(addr), protection_type, key_type);
194           return 0;
195 }
196 
197 
supp_cancel_auth_timeout(void * ctx)198 static void supp_cancel_auth_timeout(void *ctx)
199 {
200           wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
201 }
202 
203 
supp_deauthenticate(void * ctx,u16 reason_code)204 static void supp_deauthenticate(void *ctx, u16 reason_code)
205 {
206           wpa_printf(MSG_DEBUG, "SUPP: %s (TODO)", __func__);
207 }
208 
209 
supp_reconnect(void * ctx)210 static void supp_reconnect(void *ctx)
211 {
212           wpa_printf(MSG_DEBUG, "SUPP: %s (TODO)", __func__);
213 }
214 
215 
ibss_rsn_supp_init(struct ibss_rsn_peer * peer,const u8 * own_addr,const u8 * psk)216 static int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
217                                     const u8 *psk)
218 {
219           struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
220           if (ctx == NULL)
221                     return -1;
222 
223           ctx->ctx = peer;
224           ctx->msg_ctx = peer->ibss_rsn->wpa_s;
225           ctx->set_state = supp_set_state;
226           ctx->get_state = supp_get_state;
227           ctx->ether_send = supp_ether_send;
228           ctx->get_beacon_ie = supp_get_beacon_ie;
229           ctx->alloc_eapol = supp_alloc_eapol;
230           ctx->set_key = supp_set_key;
231           ctx->get_network_ctx = supp_get_network_ctx;
232           ctx->mlme_setprotection = supp_mlme_setprotection;
233           ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
234           ctx->deauthenticate = supp_deauthenticate;
235           ctx->reconnect = supp_reconnect;
236           peer->supp = wpa_sm_init(ctx);
237           if (peer->supp == NULL) {
238                     wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
239                     os_free(ctx);
240                     return -1;
241           }
242 
243           wpa_sm_set_own_addr(peer->supp, own_addr);
244           wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
245           wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
246           wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
247           wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
248           wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
249           wpa_sm_set_pmk(peer->supp, psk, PMK_LEN, NULL, NULL);
250 
251           peer->supp_ie_len = sizeof(peer->supp_ie);
252           if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
253                                                       &peer->supp_ie_len) < 0) {
254                     wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
255                                  " failed");
256                     return -1;
257           }
258 
259           wpa_sm_notify_assoc(peer->supp, peer->addr);
260 
261           return 0;
262 }
263 
264 
auth_logger(void * ctx,const u8 * addr,logger_level level,const char * txt)265 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
266                               const char *txt)
267 {
268           if (addr)
269                     wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
270                                  MAC2STR(addr), txt);
271           else
272                     wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
273 }
274 
275 
auth_get_psk(void * ctx,const u8 * addr,const u8 * p2p_dev_addr,const u8 * prev_psk,size_t * psk_len,int * vlan_id)276 static const u8 * auth_get_psk(void *ctx, const u8 *addr,
277                                      const u8 *p2p_dev_addr, const u8 *prev_psk,
278                                      size_t *psk_len, int *vlan_id)
279 {
280           struct ibss_rsn *ibss_rsn = ctx;
281 
282           if (psk_len)
283                     *psk_len = PMK_LEN;
284           if (vlan_id)
285                     *vlan_id = 0;
286           wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
287                        __func__, MAC2STR(addr), prev_psk);
288           if (prev_psk)
289                     return NULL;
290           return ibss_rsn->psk;
291 }
292 
293 
auth_send_eapol(void * ctx,const u8 * addr,const u8 * data,size_t data_len,int encrypt)294 static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
295                                  size_t data_len, int encrypt)
296 {
297           struct ibss_rsn *ibss_rsn = ctx;
298           struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
299 
300           wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
301                        "encrypt=%d)",
302                        __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
303 
304           if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_CONTROL_PORT)
305                     return wpa_drv_tx_control_port(wpa_s, addr, ETH_P_EAPOL,
306                                                          data, data_len, !encrypt);
307 
308           if (wpa_s->l2)
309                     return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
310                                               data_len);
311 
312           return -1;
313 }
314 
315 
auth_set_key(void * ctx,int vlan_id,enum wpa_alg alg,const u8 * addr,int idx,u8 * key,size_t key_len,enum key_flag key_flag)316 static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
317                               const u8 *addr, int idx, u8 *key, size_t key_len,
318                               enum key_flag key_flag)
319 {
320           struct ibss_rsn *ibss_rsn = ctx;
321           u8 seq[6];
322 
323           os_memset(seq, 0, sizeof(seq));
324 
325           if (addr) {
326                     wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
327                                  " key_idx=%d)",
328                                  __func__, alg, MAC2STR(addr), idx);
329           } else {
330                     wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
331                                  __func__, alg, idx);
332           }
333           wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
334 
335           if (idx == 0) {
336                     if (addr) {
337                               struct ibss_rsn_peer *peer;
338                               peer = ibss_rsn_get_peer(ibss_rsn, addr);
339                               if (peer) {
340                                         peer->authentication_status |=
341                                                   IBSS_RSN_SET_PTK_AUTH;
342                                         ibss_check_rsn_completed(peer);
343                               }
344                     }
345                     /*
346                      * In IBSS RSN, the pairwise key from the 4-way handshake
347                      * initiated by the peer with highest MAC address is used.
348                      */
349                     if (addr == NULL ||
350                         os_memcmp(ibss_rsn->wpa_s->own_addr, addr, ETH_ALEN) < 0) {
351                               wpa_printf(MSG_DEBUG, "AUTH: Do not use this PTK");
352                               return 0;
353                     }
354           }
355 
356           return wpa_drv_set_key(ibss_rsn->wpa_s, -1, alg, addr, idx,
357                                      1, seq, 6, key, key_len, key_flag);
358 }
359 
360 
ibss_rsn_disconnect(void * ctx,const u8 * addr,u16 reason)361 static void ibss_rsn_disconnect(void *ctx, const u8 *addr, u16 reason)
362 {
363           struct ibss_rsn *ibss_rsn = ctx;
364           wpa_drv_sta_deauth(ibss_rsn->wpa_s, addr, reason);
365 }
366 
367 
auth_for_each_sta(void * ctx,int (* cb)(struct wpa_state_machine * sm,void * ctx),void * cb_ctx)368 static int auth_for_each_sta(void *ctx, int (*cb)(struct wpa_state_machine *sm,
369                                                               void *ctx),
370                                    void *cb_ctx)
371 {
372           struct ibss_rsn *ibss_rsn = ctx;
373           struct ibss_rsn_peer *peer;
374 
375           wpa_printf(MSG_DEBUG, "AUTH: for_each_sta");
376 
377           for (peer = ibss_rsn->peers; peer; peer = peer->next) {
378                     if (peer->auth && cb(peer->auth, cb_ctx))
379                               return 1;
380           }
381 
382           return 0;
383 }
384 
385 
ibss_set_sta_authorized(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,int authorized)386 static void ibss_set_sta_authorized(struct ibss_rsn *ibss_rsn,
387                                             struct ibss_rsn_peer *peer, int authorized)
388 {
389           int res;
390 
391           if (authorized) {
392                     res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
393                                                       WPA_STA_AUTHORIZED,
394                                                       WPA_STA_AUTHORIZED, ~0);
395                     wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " authorizing port",
396                                  MAC2STR(peer->addr));
397           } else {
398                     res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
399                                                       0, 0, ~WPA_STA_AUTHORIZED);
400                     wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " unauthorizing port",
401                                  MAC2STR(peer->addr));
402           }
403 
404           if (res && errno != ENOENT) {
405                     wpa_printf(MSG_DEBUG, "Could not set station " MACSTR " flags "
406                                  "for kernel driver (errno=%d)",
407                                  MAC2STR(peer->addr), errno);
408           }
409 }
410 
411 
auth_set_eapol(void * ctx,const u8 * addr,wpa_eapol_variable var,int value)412 static void auth_set_eapol(void *ctx, const u8 *addr,
413                                                wpa_eapol_variable var, int value)
414 {
415           struct ibss_rsn *ibss_rsn = ctx;
416           struct ibss_rsn_peer *peer = ibss_rsn_get_peer(ibss_rsn, addr);
417 
418           if (peer == NULL)
419                     return;
420 
421           switch (var) {
422           case WPA_EAPOL_authorized:
423                     ibss_set_sta_authorized(ibss_rsn, peer, value);
424                     break;
425           default:
426                     /* do not handle any other event */
427                     wpa_printf(MSG_DEBUG, "AUTH: eapol event not handled %d", var);
428                     break;
429           }
430 }
431 
432 
ibss_rsn_auth_init_group(struct ibss_rsn * ibss_rsn,const u8 * own_addr,struct wpa_ssid * ssid)433 static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
434                                             const u8 *own_addr, struct wpa_ssid *ssid)
435 {
436           struct wpa_auth_config conf;
437           static const struct wpa_auth_callbacks cb = {
438                     .logger = auth_logger,
439                     .set_eapol = auth_set_eapol,
440                     .send_eapol = auth_send_eapol,
441                     .get_psk = auth_get_psk,
442                     .set_key = auth_set_key,
443                     .for_each_sta = auth_for_each_sta,
444                     .disconnect = ibss_rsn_disconnect,
445           };
446 
447           wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
448 
449           os_memset(&conf, 0, sizeof(conf));
450           conf.wpa = 2;
451           conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
452           conf.wpa_pairwise = WPA_CIPHER_CCMP;
453           conf.rsn_pairwise = WPA_CIPHER_CCMP;
454           conf.wpa_group = WPA_CIPHER_CCMP;
455           conf.eapol_version = 2;
456           conf.wpa_group_rekey = ssid->group_rekey ? ssid->group_rekey : 600;
457           conf.wpa_group_update_count = 4;
458           conf.wpa_pairwise_update_count = 4;
459 
460           ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb, ibss_rsn);
461           if (ibss_rsn->auth_group == NULL) {
462                     wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
463                     return -1;
464           }
465 
466           wpa_init_keys(ibss_rsn->auth_group);
467 
468           return 0;
469 }
470 
471 
ibss_rsn_auth_init(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer)472 static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
473                                     struct ibss_rsn_peer *peer)
474 {
475           peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr, NULL);
476           if (peer->auth == NULL) {
477                     wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
478                     return -1;
479           }
480 
481           /* TODO: get peer RSN IE with Probe Request */
482           if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth, 0,
483                                         (u8 *) "\x30\x14\x01\x00"
484                                         "\x00\x0f\xac\x04"
485                                         "\x01\x00\x00\x0f\xac\x04"
486                                         "\x01\x00\x00\x0f\xac\x02"
487                                         "\x00\x00", 22, NULL, 0, NULL, 0, NULL, 0,
488                                         NULL) != WPA_IE_OK) {
489                     wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
490                     return -1;
491           }
492 
493           if (wpa_auth_sm_event(peer->auth, WPA_ASSOC))
494                     return -1;
495 
496           if (wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth))
497                     return -1;
498 
499           return 0;
500 }
501 
502 
ibss_rsn_send_auth(struct ibss_rsn * ibss_rsn,const u8 * da,int seq)503 static int ibss_rsn_send_auth(struct ibss_rsn *ibss_rsn, const u8 *da, int seq)
504 {
505           struct ieee80211_mgmt auth;
506           const size_t auth_length = IEEE80211_HDRLEN + sizeof(auth.u.auth);
507           struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
508 
509           os_memset(&auth, 0, sizeof(auth));
510 
511           auth.frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
512                                                     WLAN_FC_STYPE_AUTH);
513           os_memcpy(auth.da, da, ETH_ALEN);
514           os_memcpy(auth.sa, wpa_s->own_addr, ETH_ALEN);
515           os_memcpy(auth.bssid, wpa_s->bssid, ETH_ALEN);
516 
517           auth.u.auth.auth_alg = host_to_le16(WLAN_AUTH_OPEN);
518           auth.u.auth.auth_transaction = host_to_le16(seq);
519           auth.u.auth.status_code = host_to_le16(WLAN_STATUS_SUCCESS);
520 
521           wpa_printf(MSG_DEBUG, "RSN: IBSS TX Auth frame (SEQ %d) to " MACSTR,
522                        seq, MAC2STR(da));
523 
524           return wpa_drv_send_mlme(wpa_s, (u8 *) &auth, auth_length, 0, 0, 0);
525 }
526 
527 
ibss_rsn_is_auth_started(struct ibss_rsn_peer * peer)528 static int ibss_rsn_is_auth_started(struct ibss_rsn_peer * peer)
529 {
530           return peer->authentication_status &
531                  (IBSS_RSN_AUTH_BY_US | IBSS_RSN_AUTH_EAPOL_BY_US);
532 }
533 
534 
535 static struct ibss_rsn_peer *
ibss_rsn_peer_init(struct ibss_rsn * ibss_rsn,const u8 * addr)536 ibss_rsn_peer_init(struct ibss_rsn *ibss_rsn, const u8 *addr)
537 {
538           struct ibss_rsn_peer *peer;
539           if (ibss_rsn == NULL)
540                     return NULL;
541 
542           peer = ibss_rsn_get_peer(ibss_rsn, addr);
543           if (peer) {
544                     wpa_printf(MSG_DEBUG, "RSN: IBSS Supplicant for peer "MACSTR
545                                  " already running", MAC2STR(addr));
546                     return peer;
547           }
548 
549           wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Supplicant for peer "MACSTR,
550                        MAC2STR(addr));
551 
552           peer = os_zalloc(sizeof(*peer));
553           if (peer == NULL) {
554                     wpa_printf(MSG_DEBUG, "RSN: Could not allocate memory.");
555                     return NULL;
556           }
557 
558           peer->ibss_rsn = ibss_rsn;
559           os_memcpy(peer->addr, addr, ETH_ALEN);
560           peer->authentication_status = IBSS_RSN_AUTH_NOT_AUTHENTICATED;
561 
562           if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr,
563                                      ibss_rsn->psk) < 0) {
564                     ibss_rsn_free(peer);
565                     return NULL;
566           }
567 
568           peer->next = ibss_rsn->peers;
569           ibss_rsn->peers = peer;
570 
571           return peer;
572 }
573 
574 
ibss_rsn_auth_timeout(void * eloop_ctx,void * timeout_ctx)575 static void ibss_rsn_auth_timeout(void *eloop_ctx, void *timeout_ctx)
576 {
577           struct ibss_rsn_peer *peer = eloop_ctx;
578 
579           /*
580            * Assume peer does not support Authentication exchange or the frame was
581            * lost somewhere - start EAPOL Authenticator.
582            */
583           wpa_printf(MSG_DEBUG,
584                        "RSN: Timeout on waiting Authentication frame response from "
585                        MACSTR " - start authenticator", MAC2STR(peer->addr));
586 
587           peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
588           ibss_rsn_auth_init(peer->ibss_rsn, peer);
589 }
590 
591 
ibss_rsn_start(struct ibss_rsn * ibss_rsn,const u8 * addr)592 int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
593 {
594           struct ibss_rsn_peer *peer;
595           int res;
596 
597           if (!ibss_rsn)
598                     return -1;
599 
600           /* if the peer already exists, exit immediately */
601           peer = ibss_rsn_get_peer(ibss_rsn, addr);
602           if (peer)
603                     return 0;
604 
605           peer = ibss_rsn_peer_init(ibss_rsn, addr);
606           if (peer == NULL)
607                     return -1;
608 
609           /* Open Authentication: send first Authentication frame */
610           res = ibss_rsn_send_auth(ibss_rsn, addr, 1);
611           if (res) {
612                     /*
613                      * The driver may not support Authentication frame exchange in
614                      * IBSS. Ignore authentication and go through EAPOL exchange.
615                      */
616                     peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
617                     return ibss_rsn_auth_init(ibss_rsn, peer);
618           } else {
619                     os_get_reltime(&peer->own_auth_tx);
620                     eloop_register_timeout(1, 0, ibss_rsn_auth_timeout, peer, NULL);
621           }
622 
623           return 0;
624 }
625 
626 
ibss_rsn_peer_authenticated(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,int reason)627 static int ibss_rsn_peer_authenticated(struct ibss_rsn *ibss_rsn,
628                                                struct ibss_rsn_peer *peer, int reason)
629 {
630           int already_started;
631 
632           if (ibss_rsn == NULL || peer == NULL)
633                     return -1;
634 
635           already_started = ibss_rsn_is_auth_started(peer);
636           peer->authentication_status |= reason;
637 
638           if (already_started) {
639                     wpa_printf(MSG_DEBUG, "RSN: IBSS Authenticator already "
640                                  "started for peer " MACSTR, MAC2STR(peer->addr));
641                     return 0;
642           }
643 
644           wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator "
645                        "for now-authenticated peer " MACSTR, MAC2STR(peer->addr));
646 
647           return ibss_rsn_auth_init(ibss_rsn, peer);
648 }
649 
650 
ibss_rsn_stop(struct ibss_rsn * ibss_rsn,const u8 * peermac)651 void ibss_rsn_stop(struct ibss_rsn *ibss_rsn, const u8 *peermac)
652 {
653           struct ibss_rsn_peer *peer, *prev;
654 
655           if (ibss_rsn == NULL)
656                     return;
657 
658           if (peermac == NULL) {
659                     /* remove all peers */
660                     wpa_printf(MSG_DEBUG, "%s: Remove all peers", __func__);
661                     peer = ibss_rsn->peers;
662                     while (peer) {
663                               prev = peer;
664                               peer = peer->next;
665                               ibss_rsn_free(prev);
666                               ibss_rsn->peers = peer;
667                     }
668           } else {
669                     /* remove specific peer */
670                     wpa_printf(MSG_DEBUG, "%s: Remove specific peer " MACSTR,
671                                  __func__, MAC2STR(peermac));
672 
673                     for (prev = NULL, peer = ibss_rsn->peers; peer != NULL;
674                          prev = peer, peer = peer->next) {
675                               if (ether_addr_equal(peermac, peer->addr)) {
676                                         if (prev == NULL)
677                                                   ibss_rsn->peers = peer->next;
678                                         else
679                                                   prev->next = peer->next;
680                                         ibss_rsn_free(peer);
681                                         wpa_printf(MSG_DEBUG, "%s: Successfully "
682                                                      "removed a specific peer",
683                                                      __func__);
684                                         break;
685                               }
686                     }
687           }
688 }
689 
690 
ibss_rsn_init(struct wpa_supplicant * wpa_s,struct wpa_ssid * ssid)691 struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s,
692                                         struct wpa_ssid *ssid)
693 {
694           struct ibss_rsn *ibss_rsn;
695 
696           ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
697           if (ibss_rsn == NULL)
698                     return NULL;
699           ibss_rsn->wpa_s = wpa_s;
700 
701           if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr, ssid) < 0) {
702                     ibss_rsn_deinit(ibss_rsn);
703                     return NULL;
704           }
705 
706           return ibss_rsn;
707 }
708 
709 
ibss_rsn_deinit(struct ibss_rsn * ibss_rsn)710 void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
711 {
712           struct ibss_rsn_peer *peer, *prev;
713 
714           if (ibss_rsn == NULL)
715                     return;
716 
717           peer = ibss_rsn->peers;
718           while (peer) {
719                     prev = peer;
720                     peer = peer->next;
721                     ibss_rsn_free(prev);
722           }
723 
724           if (ibss_rsn->auth_group)
725                     wpa_deinit(ibss_rsn->auth_group);
726           os_free(ibss_rsn);
727 
728 }
729 
730 
ibss_rsn_eapol_dst_supp(const u8 * buf,size_t len)731 static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
732 {
733           const struct ieee802_1x_hdr *hdr;
734           const struct wpa_eapol_key *key;
735           u16 key_info;
736           size_t plen;
737 
738           /* TODO: Support other EAPOL packets than just EAPOL-Key */
739 
740           if (len < sizeof(*hdr) + sizeof(*key))
741                     return -1;
742 
743           hdr = (const struct ieee802_1x_hdr *) buf;
744           key = (const struct wpa_eapol_key *) (hdr + 1);
745           plen = be_to_host16(hdr->length);
746 
747           if (hdr->version < EAPOL_VERSION) {
748                     /* TODO: backwards compatibility */
749           }
750           if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
751                     wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
752                               "not a Key frame", hdr->type);
753                     return -1;
754           }
755           if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
756                     wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
757                                  "invalid (frame size %lu)",
758                                  (unsigned long) plen, (unsigned long) len);
759                     return -1;
760           }
761 
762           if (key->type != EAPOL_KEY_TYPE_RSN) {
763                     wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
764                                  "discarded", key->type);
765                     return -1;
766           }
767 
768           key_info = WPA_GET_BE16(key->key_info);
769 
770           return !!(key_info & WPA_KEY_INFO_ACK);
771 }
772 
773 
ibss_rsn_process_rx_eapol(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,const u8 * buf,size_t len,enum frame_encryption encrypted)774 static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
775                                              struct ibss_rsn_peer *peer,
776                                              const u8 *buf, size_t len,
777                                              enum frame_encryption encrypted)
778 {
779           int supp;
780           u8 *tmp;
781 
782           supp = ibss_rsn_eapol_dst_supp(buf, len);
783           if (supp < 0)
784                     return -1;
785 
786           tmp = os_memdup(buf, len);
787           if (tmp == NULL)
788                     return -1;
789           if (supp) {
790                     peer->authentication_status |= IBSS_RSN_AUTH_EAPOL_BY_PEER;
791                     wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant from "
792                                  MACSTR, MAC2STR(peer->addr));
793                     wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len, encrypted);
794           } else {
795                     if (ibss_rsn_is_auth_started(peer) == 0) {
796                               wpa_printf(MSG_DEBUG, "RSN: IBSS EAPOL for "
797                                            "Authenticator dropped as " MACSTR " is not "
798                                            "authenticated", MAC2STR(peer->addr));
799                               os_free(tmp);
800                               return -1;
801                     }
802 
803                     wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator "
804                                  "from "MACSTR, MAC2STR(peer->addr));
805                     wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
806           }
807           os_free(tmp);
808 
809           return 1;
810 }
811 
812 
ibss_rsn_rx_eapol(struct ibss_rsn * ibss_rsn,const u8 * src_addr,const u8 * buf,size_t len,enum frame_encryption encrypted)813 int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
814                           const u8 *buf, size_t len,
815                           enum frame_encryption encrypted)
816 {
817           struct ibss_rsn_peer *peer;
818 
819           if (ibss_rsn == NULL)
820                     return -1;
821 
822           peer = ibss_rsn_get_peer(ibss_rsn, src_addr);
823           if (peer)
824                     return ibss_rsn_process_rx_eapol(ibss_rsn, peer, buf, len,
825                                                              encrypted);
826 
827           if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
828                     /*
829                      * Create new IBSS peer based on an EAPOL message from the peer
830                      * Authenticator.
831                      */
832                     peer = ibss_rsn_peer_init(ibss_rsn, src_addr);
833                     if (peer == NULL)
834                               return -1;
835 
836                     /* assume the peer is authenticated already */
837                     wpa_printf(MSG_DEBUG, "RSN: IBSS Not using IBSS Auth for peer "
838                                  MACSTR, MAC2STR(src_addr));
839                     ibss_rsn_peer_authenticated(ibss_rsn, peer,
840                                                       IBSS_RSN_AUTH_EAPOL_BY_US);
841 
842                     return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
843                                                              buf, len, encrypted);
844           }
845 
846           return 0;
847 }
848 
ibss_rsn_set_psk(struct ibss_rsn * ibss_rsn,const u8 * psk)849 void ibss_rsn_set_psk(struct ibss_rsn *ibss_rsn, const u8 *psk)
850 {
851           if (ibss_rsn == NULL)
852                     return;
853           os_memcpy(ibss_rsn->psk, psk, PMK_LEN);
854 }
855 
856 
ibss_rsn_handle_auth_1_of_2(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,const u8 * addr)857 static void ibss_rsn_handle_auth_1_of_2(struct ibss_rsn *ibss_rsn,
858                                                   struct ibss_rsn_peer *peer,
859                                                   const u8* addr)
860 {
861           wpa_printf(MSG_DEBUG, "RSN: IBSS RX Auth frame (SEQ 1) from " MACSTR,
862                        MAC2STR(addr));
863 
864           if (peer &&
865               peer->authentication_status & (IBSS_RSN_SET_PTK_SUPP |
866                                                      IBSS_RSN_SET_PTK_AUTH)) {
867                     /* Clear the TK for this pair to allow recovery from the case
868                      * where the peer STA has restarted and lost its key while we
869                      * still have a pairwise key configured. */
870                     wpa_printf(MSG_DEBUG, "RSN: Clear pairwise key for peer "
871                                  MACSTR, MAC2STR(addr));
872                     wpa_drv_set_key(ibss_rsn->wpa_s, -1, WPA_ALG_NONE, addr, 0, 0,
873                                         NULL, 0, NULL, 0, KEY_FLAG_PAIRWISE);
874           }
875 
876           if (peer &&
877               peer->authentication_status & IBSS_RSN_AUTH_EAPOL_BY_PEER) {
878                     if (peer->own_auth_tx.sec) {
879                               struct os_reltime now, diff;
880                               os_get_reltime(&now);
881                               os_reltime_sub(&now, &peer->own_auth_tx, &diff);
882                               if (diff.sec == 0 && diff.usec < 500000) {
883                                         wpa_printf(MSG_DEBUG, "RSN: Skip IBSS reinit since only %u usec from own Auth frame TX",
884                                                      (int) diff.usec);
885                                         goto skip_reinit;
886                               }
887                     }
888                     /*
889                      * A peer sent us an Authentication frame even though it already
890                      * started an EAPOL session. We should reinit state machines
891                      * here, but it's much more complicated than just deleting and
892                      * recreating the state machine
893                      */
894                     wpa_printf(MSG_DEBUG, "RSN: IBSS Reinitializing station "
895                                  MACSTR, MAC2STR(addr));
896 
897                     ibss_rsn_stop(ibss_rsn, addr);
898                     peer = NULL;
899           }
900 
901           if (!peer) {
902                     peer = ibss_rsn_peer_init(ibss_rsn, addr);
903                     if (!peer)
904                               return;
905 
906                     wpa_printf(MSG_DEBUG, "RSN: IBSS Auth started by peer " MACSTR,
907                                  MAC2STR(addr));
908           }
909 
910 skip_reinit:
911           /* reply with an Authentication frame now, before sending an EAPOL */
912           ibss_rsn_send_auth(ibss_rsn, addr, 2);
913           /* no need to start another AUTH challenge in the other way.. */
914           ibss_rsn_peer_authenticated(ibss_rsn, peer, IBSS_RSN_AUTH_EAPOL_BY_US);
915 }
916 
917 
ibss_rsn_handle_auth(struct ibss_rsn * ibss_rsn,const u8 * auth_frame,size_t len)918 void ibss_rsn_handle_auth(struct ibss_rsn *ibss_rsn, const u8 *auth_frame,
919                                 size_t len)
920 {
921           const struct ieee80211_mgmt *header;
922           struct ibss_rsn_peer *peer;
923           size_t auth_length;
924 
925           header = (const struct ieee80211_mgmt *) auth_frame;
926           auth_length = IEEE80211_HDRLEN + sizeof(header->u.auth);
927 
928           if (ibss_rsn == NULL || len < auth_length)
929                     return;
930 
931           if (le_to_host16(header->u.auth.auth_alg) != WLAN_AUTH_OPEN ||
932               le_to_host16(header->u.auth.status_code) != WLAN_STATUS_SUCCESS)
933                     return;
934 
935           peer = ibss_rsn_get_peer(ibss_rsn, header->sa);
936 
937           switch (le_to_host16(header->u.auth.auth_transaction)) {
938           case 1:
939                     ibss_rsn_handle_auth_1_of_2(ibss_rsn, peer, header->sa);
940                     break;
941           case 2:
942                     wpa_printf(MSG_DEBUG, "RSN: IBSS RX Auth frame (SEQ 2) from "
943                                  MACSTR, MAC2STR(header->sa));
944                     if (!peer) {
945                               wpa_printf(MSG_DEBUG, "RSN: Received Auth seq 2 from "
946                                            "unknown STA " MACSTR, MAC2STR(header->sa));
947                               break;
948                     }
949 
950                     /* authentication has been completed */
951                     eloop_cancel_timeout(ibss_rsn_auth_timeout, peer, NULL);
952                     wpa_printf(MSG_DEBUG, "RSN: IBSS Auth completed with " MACSTR,
953                                  MAC2STR(header->sa));
954                     ibss_rsn_peer_authenticated(ibss_rsn, peer,
955                                                       IBSS_RSN_AUTH_BY_US);
956                     break;
957           }
958 }
959