1 /*
2 * EAP-WSC peer for Wi-Fi Protected Setup
3 * Copyright (c) 2007-2009, 2012, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "uuid.h"
13 #include "eap_i.h"
14 #include "eap_common/eap_wsc_common.h"
15 #include "wps/wps.h"
16 #include "wps/wps_defs.h"
17
18
19 struct eap_wsc_data {
20 enum { WAIT_START, MESG, WAIT_FRAG_ACK, FAIL } state;
21 int registrar;
22 struct wpabuf *in_buf;
23 struct wpabuf *out_buf;
24 enum wsc_op_code in_op_code, out_op_code;
25 size_t out_used;
26 size_t fragment_size;
27 struct wps_data *wps;
28 struct wps_context *wps_ctx;
29 };
30
31
eap_wsc_state_txt(int state)32 static const char * eap_wsc_state_txt(int state)
33 {
34 switch (state) {
35 case WAIT_START:
36 return "WAIT_START";
37 case MESG:
38 return "MESG";
39 case WAIT_FRAG_ACK:
40 return "WAIT_FRAG_ACK";
41 case FAIL:
42 return "FAIL";
43 default:
44 return "?";
45 }
46 }
47
48
eap_wsc_state(struct eap_wsc_data * data,int state)49 static void eap_wsc_state(struct eap_wsc_data *data, int state)
50 {
51 wpa_printf(MSG_DEBUG, "EAP-WSC: %s -> %s",
52 eap_wsc_state_txt(data->state),
53 eap_wsc_state_txt(state));
54 data->state = state;
55 }
56
57
eap_wsc_new_ap_settings(struct wps_credential * cred,const char * params)58 static int eap_wsc_new_ap_settings(struct wps_credential *cred,
59 const char *params)
60 {
61 const char *pos, *end;
62 size_t len;
63
64 os_memset(cred, 0, sizeof(*cred));
65
66 pos = os_strstr(params, "new_ssid=");
67 if (pos == NULL)
68 return 0;
69 pos += 9;
70 end = os_strchr(pos, ' ');
71 if (end == NULL)
72 len = os_strlen(pos);
73 else
74 len = end - pos;
75 if ((len & 1) || len > 2 * sizeof(cred->ssid) ||
76 hexstr2bin(pos, cred->ssid, len / 2)) {
77 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid new_ssid");
78 return -1;
79 }
80 cred->ssid_len = len / 2;
81
82 pos = os_strstr(params, "new_auth=");
83 if (pos == NULL) {
84 wpa_printf(MSG_DEBUG, "EAP-WSC: Missing new_auth");
85 return -1;
86 }
87 if (os_strncmp(pos + 9, "OPEN", 4) == 0)
88 cred->auth_type = WPS_AUTH_OPEN;
89 else if (os_strncmp(pos + 9, "WPAPSK", 6) == 0)
90 cred->auth_type = WPS_AUTH_WPAPSK;
91 else if (os_strncmp(pos + 9, "WPA2PSK", 7) == 0)
92 cred->auth_type = WPS_AUTH_WPA2PSK;
93 else {
94 wpa_printf(MSG_DEBUG, "EAP-WSC: Unknown new_auth");
95 return -1;
96 }
97
98 pos = os_strstr(params, "new_encr=");
99 if (pos == NULL) {
100 wpa_printf(MSG_DEBUG, "EAP-WSC: Missing new_encr");
101 return -1;
102 }
103 if (os_strncmp(pos + 9, "NONE", 4) == 0)
104 cred->encr_type = WPS_ENCR_NONE;
105 #ifdef CONFIG_TESTING_OPTIONS
106 else if (os_strncmp(pos + 9, "WEP", 3) == 0)
107 cred->encr_type = WPS_ENCR_WEP;
108 #endif /* CONFIG_TESTING_OPTIONS */
109 else if (os_strncmp(pos + 9, "TKIP", 4) == 0)
110 cred->encr_type = WPS_ENCR_TKIP;
111 else if (os_strncmp(pos + 9, "CCMP", 4) == 0)
112 cred->encr_type = WPS_ENCR_AES;
113 else {
114 wpa_printf(MSG_DEBUG, "EAP-WSC: Unknown new_encr");
115 return -1;
116 }
117
118 pos = os_strstr(params, "new_key=");
119 if (pos == NULL)
120 return 0;
121 pos += 8;
122 end = os_strchr(pos, ' ');
123 if (end == NULL)
124 len = os_strlen(pos);
125 else
126 len = end - pos;
127 if ((len & 1) || len > 2 * sizeof(cred->key) ||
128 hexstr2bin(pos, cred->key, len / 2)) {
129 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid new_key");
130 return -1;
131 }
132 cred->key_len = len / 2;
133
134 return 1;
135 }
136
137
eap_wsc_init(struct eap_sm * sm)138 static void * eap_wsc_init(struct eap_sm *sm)
139 {
140 struct eap_wsc_data *data;
141 const u8 *identity;
142 size_t identity_len;
143 int registrar;
144 struct wps_config cfg;
145 const char *pos, *end;
146 const char *phase1;
147 struct wps_context *wps;
148 struct wps_credential new_ap_settings;
149 int res;
150 int nfc = 0;
151 u8 pkhash[WPS_OOB_PUBKEY_HASH_LEN];
152
153 wps = sm->wps;
154 if (wps == NULL) {
155 wpa_printf(MSG_ERROR, "EAP-WSC: WPS context not available");
156 return NULL;
157 }
158
159 identity = eap_get_config_identity(sm, &identity_len);
160
161 if (identity && identity_len == WSC_ID_REGISTRAR_LEN &&
162 os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0)
163 registrar = 1; /* Supplicant is Registrar */
164 else if (identity && identity_len == WSC_ID_ENROLLEE_LEN &&
165 os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0)
166 registrar = 0; /* Supplicant is Enrollee */
167 else {
168 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
169 identity, identity_len);
170 return NULL;
171 }
172
173 data = os_zalloc(sizeof(*data));
174 if (data == NULL)
175 return NULL;
176 data->state = registrar ? MESG : WAIT_START;
177 data->registrar = registrar;
178 data->wps_ctx = wps;
179
180 os_memset(&cfg, 0, sizeof(cfg));
181 cfg.wps = wps;
182 cfg.registrar = registrar;
183
184 phase1 = eap_get_config_phase1(sm);
185 if (phase1 == NULL) {
186 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
187 "set");
188 os_free(data);
189 return NULL;
190 }
191
192 pos = os_strstr(phase1, "pin=");
193 if (pos) {
194 pos += 4;
195 cfg.pin = (const u8 *) pos;
196 while (*pos != '\0' && *pos != ' ')
197 pos++;
198 cfg.pin_len = pos - (const char *) cfg.pin;
199 if (cfg.pin_len == 6 &&
200 os_strncmp((const char *) cfg.pin, "nfc-pw", 6) == 0) {
201 cfg.pin = NULL;
202 cfg.pin_len = 0;
203 nfc = 1;
204 }
205 } else {
206 pos = os_strstr(phase1, "pbc=1");
207 if (pos)
208 cfg.pbc = 1;
209 }
210
211 pos = os_strstr(phase1, "dev_pw_id=");
212 if (pos) {
213 u16 id = atoi(pos + 10);
214 if (id == DEV_PW_NFC_CONNECTION_HANDOVER)
215 nfc = 1;
216 if (cfg.pin || id == DEV_PW_NFC_CONNECTION_HANDOVER)
217 cfg.dev_pw_id = id;
218 }
219
220 if (cfg.pin == NULL && !cfg.pbc && !nfc) {
221 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
222 "configuration data");
223 os_free(data);
224 return NULL;
225 }
226
227 pos = os_strstr(phase1, " pkhash=");
228 if (pos) {
229 size_t len;
230 pos += 8;
231 end = os_strchr(pos, ' ');
232 if (end)
233 len = end - pos;
234 else
235 len = os_strlen(pos);
236 if (len != 2 * WPS_OOB_PUBKEY_HASH_LEN ||
237 hexstr2bin(pos, pkhash, WPS_OOB_PUBKEY_HASH_LEN)) {
238 wpa_printf(MSG_INFO, "EAP-WSC: Invalid pkhash");
239 os_free(data);
240 return NULL;
241 }
242 cfg.peer_pubkey_hash = pkhash;
243 }
244
245 res = eap_wsc_new_ap_settings(&new_ap_settings, phase1);
246 if (res < 0) {
247 os_free(data);
248 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to parse new AP "
249 "settings");
250 return NULL;
251 }
252 if (res == 1) {
253 wpa_printf(MSG_DEBUG, "EAP-WSC: Provide new AP settings for "
254 "WPS");
255 cfg.new_ap_settings = &new_ap_settings;
256 }
257
258 if (os_strstr(phase1, "multi_ap=1"))
259 cfg.multi_ap_backhaul_sta = 1;
260
261 data->wps = wps_init(&cfg);
262 if (data->wps == NULL) {
263 os_free(data);
264 wpa_printf(MSG_DEBUG, "EAP-WSC: wps_init failed");
265 return NULL;
266 }
267 res = eap_get_config_fragment_size(sm);
268 if (res > 0)
269 data->fragment_size = res;
270 else
271 data->fragment_size = WSC_FRAGMENT_SIZE;
272 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment size limit %u",
273 (unsigned int) data->fragment_size);
274
275 if (registrar && cfg.pin) {
276 wps_registrar_add_pin(data->wps_ctx->registrar, NULL, NULL,
277 cfg.pin, cfg.pin_len, 0);
278 }
279
280 /* Use reduced client timeout for WPS to avoid long wait */
281 if (sm->ClientTimeout > 30)
282 sm->ClientTimeout = 30;
283
284 return data;
285 }
286
287
eap_wsc_deinit(struct eap_sm * sm,void * priv)288 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
289 {
290 struct eap_wsc_data *data = priv;
291 wpabuf_free(data->in_buf);
292 wpabuf_free(data->out_buf);
293 wps_deinit(data->wps);
294 os_free(data->wps_ctx->network_key);
295 data->wps_ctx->network_key = NULL;
296 os_free(data);
297 }
298
299
eap_wsc_build_msg(struct eap_wsc_data * data,struct eap_method_ret * ret,u8 id)300 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
301 struct eap_method_ret *ret, u8 id)
302 {
303 struct wpabuf *resp;
304 u8 flags;
305 size_t send_len, plen;
306
307 ret->ignore = false;
308 wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
309 ret->allowNotifications = true;
310
311 flags = 0;
312 send_len = wpabuf_len(data->out_buf) - data->out_used;
313 if (2 + send_len > data->fragment_size) {
314 send_len = data->fragment_size - 2;
315 flags |= WSC_FLAGS_MF;
316 if (data->out_used == 0) {
317 flags |= WSC_FLAGS_LF;
318 send_len -= 2;
319 }
320 }
321 plen = 2 + send_len;
322 if (flags & WSC_FLAGS_LF)
323 plen += 2;
324 resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
325 EAP_CODE_RESPONSE, id);
326 if (resp == NULL)
327 return NULL;
328
329 wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
330 wpabuf_put_u8(resp, flags); /* Flags */
331 if (flags & WSC_FLAGS_LF)
332 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
333
334 wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
335 send_len);
336 data->out_used += send_len;
337
338 ret->methodState = METHOD_MAY_CONT;
339 ret->decision = DECISION_FAIL;
340
341 if (data->out_used == wpabuf_len(data->out_buf)) {
342 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
343 "(message sent completely)",
344 (unsigned long) send_len);
345 wpabuf_free(data->out_buf);
346 data->out_buf = NULL;
347 data->out_used = 0;
348 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
349 data->out_op_code == WSC_NACK ||
350 data->out_op_code == WSC_Done) {
351 eap_wsc_state(data, FAIL);
352 ret->methodState = METHOD_DONE;
353 } else
354 eap_wsc_state(data, MESG);
355 } else {
356 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
357 "(%lu more to send)", (unsigned long) send_len,
358 (unsigned long) wpabuf_len(data->out_buf) -
359 data->out_used);
360 eap_wsc_state(data, WAIT_FRAG_ACK);
361 }
362
363 return resp;
364 }
365
366
eap_wsc_process_cont(struct eap_wsc_data * data,const u8 * buf,size_t len,u8 op_code)367 static int eap_wsc_process_cont(struct eap_wsc_data *data,
368 const u8 *buf, size_t len, u8 op_code)
369 {
370 /* Process continuation of a pending message */
371 if (op_code != data->in_op_code) {
372 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
373 "fragment (expected %d)",
374 op_code, data->in_op_code);
375 return -1;
376 }
377
378 if (len > wpabuf_tailroom(data->in_buf)) {
379 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
380 eap_wsc_state(data, FAIL);
381 return -1;
382 }
383
384 wpabuf_put_data(data->in_buf, buf, len);
385 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
386 "for %lu bytes more", (unsigned long) len,
387 (unsigned long) wpabuf_tailroom(data->in_buf));
388
389 return 0;
390 }
391
392
eap_wsc_process_fragment(struct eap_wsc_data * data,struct eap_method_ret * ret,u8 id,u8 flags,u8 op_code,u16 message_length,const u8 * buf,size_t len)393 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
394 struct eap_method_ret *ret,
395 u8 id, u8 flags, u8 op_code,
396 u16 message_length,
397 const u8 *buf, size_t len)
398 {
399 /* Process a fragment that is not the last one of the message */
400 if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
401 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
402 "fragmented packet");
403 ret->ignore = true;
404 return NULL;
405 }
406
407 if (data->in_buf == NULL) {
408 /* First fragment of the message */
409 data->in_buf = wpabuf_alloc(message_length);
410 if (data->in_buf == NULL) {
411 wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
412 "message");
413 ret->ignore = true;
414 return NULL;
415 }
416 data->in_op_code = op_code;
417 wpabuf_put_data(data->in_buf, buf, len);
418 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
419 "fragment, waiting for %lu bytes more",
420 (unsigned long) len,
421 (unsigned long) wpabuf_tailroom(data->in_buf));
422 }
423
424 return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
425 }
426
427
eap_wsc_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)428 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
429 struct eap_method_ret *ret,
430 const struct wpabuf *reqData)
431 {
432 struct eap_wsc_data *data = priv;
433 const u8 *start, *pos, *end;
434 size_t len;
435 u8 op_code, flags, id;
436 u16 message_length = 0;
437 enum wps_process_res res;
438 struct wpabuf tmpbuf;
439 struct wpabuf *r;
440
441 pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
442 &len);
443 if (pos == NULL || len < 2) {
444 ret->ignore = true;
445 return NULL;
446 }
447
448 id = eap_get_id(reqData);
449
450 start = pos;
451 end = start + len;
452
453 op_code = *pos++;
454 flags = *pos++;
455 if (flags & WSC_FLAGS_LF) {
456 if (end - pos < 2) {
457 wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
458 ret->ignore = true;
459 return NULL;
460 }
461 message_length = WPA_GET_BE16(pos);
462 pos += 2;
463
464 if (message_length < end - pos || message_length > 50000) {
465 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
466 "Length");
467 ret->ignore = true;
468 return NULL;
469 }
470 }
471
472 wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
473 "Flags 0x%x Message Length %d",
474 op_code, flags, message_length);
475
476 if (data->state == WAIT_FRAG_ACK) {
477 if (op_code != WSC_FRAG_ACK) {
478 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
479 "in WAIT_FRAG_ACK state", op_code);
480 ret->ignore = true;
481 return NULL;
482 }
483 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
484 eap_wsc_state(data, MESG);
485 return eap_wsc_build_msg(data, ret, id);
486 }
487
488 if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
489 op_code != WSC_Done && op_code != WSC_Start) {
490 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
491 op_code);
492 ret->ignore = true;
493 return NULL;
494 }
495
496 if (data->state == WAIT_START) {
497 if (op_code != WSC_Start) {
498 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
499 "in WAIT_START state", op_code);
500 ret->ignore = true;
501 return NULL;
502 }
503 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
504 eap_wsc_state(data, MESG);
505 /* Start message has empty payload, skip processing */
506 goto send_msg;
507 } else if (op_code == WSC_Start) {
508 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
509 op_code);
510 ret->ignore = true;
511 return NULL;
512 }
513
514 if (data->in_buf &&
515 eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
516 ret->ignore = true;
517 return NULL;
518 }
519
520 if (flags & WSC_FLAGS_MF) {
521 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
522 message_length, pos,
523 end - pos);
524 }
525
526 if (data->in_buf == NULL) {
527 /* Wrap unfragmented messages as wpabuf without extra copy */
528 wpabuf_set(&tmpbuf, pos, end - pos);
529 data->in_buf = &tmpbuf;
530 }
531
532 res = wps_process_msg(data->wps, op_code, data->in_buf);
533 switch (res) {
534 case WPS_DONE:
535 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
536 "successfully - wait for EAP failure");
537 eap_wsc_state(data, FAIL);
538 break;
539 case WPS_CONTINUE:
540 eap_wsc_state(data, MESG);
541 break;
542 case WPS_FAILURE:
543 case WPS_PENDING:
544 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
545 eap_wsc_state(data, FAIL);
546 break;
547 }
548
549 if (data->in_buf != &tmpbuf)
550 wpabuf_free(data->in_buf);
551 data->in_buf = NULL;
552
553 send_msg:
554 if (data->out_buf == NULL) {
555 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
556 if (data->out_buf == NULL) {
557 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
558 "message from WPS");
559 eap_wsc_state(data, FAIL);
560 ret->methodState = METHOD_DONE;
561 ret->decision = DECISION_FAIL;
562 return NULL;
563 }
564 data->out_used = 0;
565 }
566
567 eap_wsc_state(data, MESG);
568 r = eap_wsc_build_msg(data, ret, id);
569 if (data->state == FAIL && ret->methodState == METHOD_DONE) {
570 /* Use reduced client timeout for WPS to avoid long wait */
571 if (sm->ClientTimeout > 2)
572 sm->ClientTimeout = 2;
573 }
574 return r;
575 }
576
577
eap_peer_wsc_register(void)578 int eap_peer_wsc_register(void)
579 {
580 struct eap_method *eap;
581
582 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
583 EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
584 "WSC");
585 if (eap == NULL)
586 return -1;
587
588 eap->init = eap_wsc_init;
589 eap->deinit = eap_wsc_deinit;
590 eap->process = eap_wsc_process;
591
592 return eap_peer_method_register(eap);
593 }
594