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 data->wps = wps_init(&cfg);
259 if (data->wps == NULL) {
260 os_free(data);
261 wpa_printf(MSG_DEBUG, "EAP-WSC: wps_init failed");
262 return NULL;
263 }
264 res = eap_get_config_fragment_size(sm);
265 if (res > 0)
266 data->fragment_size = res;
267 else
268 data->fragment_size = WSC_FRAGMENT_SIZE;
269 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment size limit %u",
270 (unsigned int) data->fragment_size);
271
272 if (registrar && cfg.pin) {
273 wps_registrar_add_pin(data->wps_ctx->registrar, NULL, NULL,
274 cfg.pin, cfg.pin_len, 0);
275 }
276
277 /* Use reduced client timeout for WPS to avoid long wait */
278 if (sm->ClientTimeout > 30)
279 sm->ClientTimeout = 30;
280
281 return data;
282 }
283
284
eap_wsc_deinit(struct eap_sm * sm,void * priv)285 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
286 {
287 struct eap_wsc_data *data = priv;
288 wpabuf_free(data->in_buf);
289 wpabuf_free(data->out_buf);
290 wps_deinit(data->wps);
291 os_free(data->wps_ctx->network_key);
292 data->wps_ctx->network_key = NULL;
293 os_free(data);
294 }
295
296
eap_wsc_build_msg(struct eap_wsc_data * data,struct eap_method_ret * ret,u8 id)297 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
298 struct eap_method_ret *ret, u8 id)
299 {
300 struct wpabuf *resp;
301 u8 flags;
302 size_t send_len, plen;
303
304 ret->ignore = FALSE;
305 wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
306 ret->allowNotifications = TRUE;
307
308 flags = 0;
309 send_len = wpabuf_len(data->out_buf) - data->out_used;
310 if (2 + send_len > data->fragment_size) {
311 send_len = data->fragment_size - 2;
312 flags |= WSC_FLAGS_MF;
313 if (data->out_used == 0) {
314 flags |= WSC_FLAGS_LF;
315 send_len -= 2;
316 }
317 }
318 plen = 2 + send_len;
319 if (flags & WSC_FLAGS_LF)
320 plen += 2;
321 resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
322 EAP_CODE_RESPONSE, id);
323 if (resp == NULL)
324 return NULL;
325
326 wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
327 wpabuf_put_u8(resp, flags); /* Flags */
328 if (flags & WSC_FLAGS_LF)
329 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
330
331 wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
332 send_len);
333 data->out_used += send_len;
334
335 ret->methodState = METHOD_MAY_CONT;
336 ret->decision = DECISION_FAIL;
337
338 if (data->out_used == wpabuf_len(data->out_buf)) {
339 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
340 "(message sent completely)",
341 (unsigned long) send_len);
342 wpabuf_free(data->out_buf);
343 data->out_buf = NULL;
344 data->out_used = 0;
345 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
346 data->out_op_code == WSC_NACK ||
347 data->out_op_code == WSC_Done) {
348 eap_wsc_state(data, FAIL);
349 ret->methodState = METHOD_DONE;
350 } else
351 eap_wsc_state(data, MESG);
352 } else {
353 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
354 "(%lu more to send)", (unsigned long) send_len,
355 (unsigned long) wpabuf_len(data->out_buf) -
356 data->out_used);
357 eap_wsc_state(data, WAIT_FRAG_ACK);
358 }
359
360 return resp;
361 }
362
363
eap_wsc_process_cont(struct eap_wsc_data * data,const u8 * buf,size_t len,u8 op_code)364 static int eap_wsc_process_cont(struct eap_wsc_data *data,
365 const u8 *buf, size_t len, u8 op_code)
366 {
367 /* Process continuation of a pending message */
368 if (op_code != data->in_op_code) {
369 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
370 "fragment (expected %d)",
371 op_code, data->in_op_code);
372 return -1;
373 }
374
375 if (len > wpabuf_tailroom(data->in_buf)) {
376 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
377 eap_wsc_state(data, FAIL);
378 return -1;
379 }
380
381 wpabuf_put_data(data->in_buf, buf, len);
382 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
383 "for %lu bytes more", (unsigned long) len,
384 (unsigned long) wpabuf_tailroom(data->in_buf));
385
386 return 0;
387 }
388
389
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)390 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
391 struct eap_method_ret *ret,
392 u8 id, u8 flags, u8 op_code,
393 u16 message_length,
394 const u8 *buf, size_t len)
395 {
396 /* Process a fragment that is not the last one of the message */
397 if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
398 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
399 "fragmented packet");
400 ret->ignore = TRUE;
401 return NULL;
402 }
403
404 if (data->in_buf == NULL) {
405 /* First fragment of the message */
406 data->in_buf = wpabuf_alloc(message_length);
407 if (data->in_buf == NULL) {
408 wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
409 "message");
410 ret->ignore = TRUE;
411 return NULL;
412 }
413 data->in_op_code = op_code;
414 wpabuf_put_data(data->in_buf, buf, len);
415 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
416 "fragment, waiting for %lu bytes more",
417 (unsigned long) len,
418 (unsigned long) wpabuf_tailroom(data->in_buf));
419 }
420
421 return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
422 }
423
424
eap_wsc_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)425 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
426 struct eap_method_ret *ret,
427 const struct wpabuf *reqData)
428 {
429 struct eap_wsc_data *data = priv;
430 const u8 *start, *pos, *end;
431 size_t len;
432 u8 op_code, flags, id;
433 u16 message_length = 0;
434 enum wps_process_res res;
435 struct wpabuf tmpbuf;
436 struct wpabuf *r;
437
438 pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
439 &len);
440 if (pos == NULL || len < 2) {
441 ret->ignore = TRUE;
442 return NULL;
443 }
444
445 id = eap_get_id(reqData);
446
447 start = pos;
448 end = start + len;
449
450 op_code = *pos++;
451 flags = *pos++;
452 if (flags & WSC_FLAGS_LF) {
453 if (end - pos < 2) {
454 wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
455 ret->ignore = TRUE;
456 return NULL;
457 }
458 message_length = WPA_GET_BE16(pos);
459 pos += 2;
460
461 if (message_length < end - pos || message_length > 50000) {
462 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
463 "Length");
464 ret->ignore = TRUE;
465 return NULL;
466 }
467 }
468
469 wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
470 "Flags 0x%x Message Length %d",
471 op_code, flags, message_length);
472
473 if (data->state == WAIT_FRAG_ACK) {
474 if (op_code != WSC_FRAG_ACK) {
475 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
476 "in WAIT_FRAG_ACK state", op_code);
477 ret->ignore = TRUE;
478 return NULL;
479 }
480 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
481 eap_wsc_state(data, MESG);
482 return eap_wsc_build_msg(data, ret, id);
483 }
484
485 if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
486 op_code != WSC_Done && op_code != WSC_Start) {
487 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
488 op_code);
489 ret->ignore = TRUE;
490 return NULL;
491 }
492
493 if (data->state == WAIT_START) {
494 if (op_code != WSC_Start) {
495 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
496 "in WAIT_START state", op_code);
497 ret->ignore = TRUE;
498 return NULL;
499 }
500 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
501 eap_wsc_state(data, MESG);
502 /* Start message has empty payload, skip processing */
503 goto send_msg;
504 } else if (op_code == WSC_Start) {
505 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
506 op_code);
507 ret->ignore = TRUE;
508 return NULL;
509 }
510
511 if (data->in_buf &&
512 eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
513 ret->ignore = TRUE;
514 return NULL;
515 }
516
517 if (flags & WSC_FLAGS_MF) {
518 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
519 message_length, pos,
520 end - pos);
521 }
522
523 if (data->in_buf == NULL) {
524 /* Wrap unfragmented messages as wpabuf without extra copy */
525 wpabuf_set(&tmpbuf, pos, end - pos);
526 data->in_buf = &tmpbuf;
527 }
528
529 res = wps_process_msg(data->wps, op_code, data->in_buf);
530 switch (res) {
531 case WPS_DONE:
532 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
533 "successfully - wait for EAP failure");
534 eap_wsc_state(data, FAIL);
535 break;
536 case WPS_CONTINUE:
537 eap_wsc_state(data, MESG);
538 break;
539 case WPS_FAILURE:
540 case WPS_PENDING:
541 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
542 eap_wsc_state(data, FAIL);
543 break;
544 }
545
546 if (data->in_buf != &tmpbuf)
547 wpabuf_free(data->in_buf);
548 data->in_buf = NULL;
549
550 send_msg:
551 if (data->out_buf == NULL) {
552 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
553 if (data->out_buf == NULL) {
554 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
555 "message from WPS");
556 eap_wsc_state(data, FAIL);
557 ret->methodState = METHOD_DONE;
558 ret->decision = DECISION_FAIL;
559 return NULL;
560 }
561 data->out_used = 0;
562 }
563
564 eap_wsc_state(data, MESG);
565 r = eap_wsc_build_msg(data, ret, id);
566 if (data->state == FAIL && ret->methodState == METHOD_DONE) {
567 /* Use reduced client timeout for WPS to avoid long wait */
568 if (sm->ClientTimeout > 2)
569 sm->ClientTimeout = 2;
570 }
571 return r;
572 }
573
574
eap_peer_wsc_register(void)575 int eap_peer_wsc_register(void)
576 {
577 struct eap_method *eap;
578
579 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
580 EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
581 "WSC");
582 if (eap == NULL)
583 return -1;
584
585 eap->init = eap_wsc_init;
586 eap->deinit = eap_wsc_deinit;
587 eap->process = eap_wsc_process;
588
589 return eap_peer_method_register(eap);
590 }
591