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, FRAG_ACK, WAIT_FRAG_ACK, DONE, 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 FRAG_ACK:
40 return "FRAG_ACK";
41 case WAIT_FRAG_ACK:
42 return "WAIT_FRAG_ACK";
43 case DONE:
44 return "DONE";
45 case FAIL:
46 return "FAIL";
47 default:
48 return "?";
49 }
50 }
51
52
eap_wsc_state(struct eap_wsc_data * data,int state)53 static void eap_wsc_state(struct eap_wsc_data *data, int state)
54 {
55 wpa_printf(MSG_DEBUG, "EAP-WSC: %s -> %s",
56 eap_wsc_state_txt(data->state),
57 eap_wsc_state_txt(state));
58 data->state = state;
59 }
60
61
eap_wsc_new_ap_settings(struct wps_credential * cred,const char * params)62 static int eap_wsc_new_ap_settings(struct wps_credential *cred,
63 const char *params)
64 {
65 const char *pos, *end;
66 size_t len;
67
68 os_memset(cred, 0, sizeof(*cred));
69
70 pos = os_strstr(params, "new_ssid=");
71 if (pos == NULL)
72 return 0;
73 pos += 9;
74 end = os_strchr(pos, ' ');
75 if (end == NULL)
76 len = os_strlen(pos);
77 else
78 len = end - pos;
79 if ((len & 1) || len > 2 * sizeof(cred->ssid) ||
80 hexstr2bin(pos, cred->ssid, len / 2)) {
81 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid new_ssid");
82 return -1;
83 }
84 cred->ssid_len = len / 2;
85
86 pos = os_strstr(params, "new_auth=");
87 if (pos == NULL) {
88 wpa_printf(MSG_DEBUG, "EAP-WSC: Missing new_auth");
89 return -1;
90 }
91 if (os_strncmp(pos + 9, "OPEN", 4) == 0)
92 cred->auth_type = WPS_AUTH_OPEN;
93 else if (os_strncmp(pos + 9, "WPAPSK", 6) == 0)
94 cred->auth_type = WPS_AUTH_WPAPSK;
95 else if (os_strncmp(pos + 9, "WPA2PSK", 7) == 0)
96 cred->auth_type = WPS_AUTH_WPA2PSK;
97 else {
98 wpa_printf(MSG_DEBUG, "EAP-WSC: Unknown new_auth");
99 return -1;
100 }
101
102 pos = os_strstr(params, "new_encr=");
103 if (pos == NULL) {
104 wpa_printf(MSG_DEBUG, "EAP-WSC: Missing new_encr");
105 return -1;
106 }
107 if (os_strncmp(pos + 9, "NONE", 4) == 0)
108 cred->encr_type = WPS_ENCR_NONE;
109 #ifdef CONFIG_TESTING_OPTIONS
110 else if (os_strncmp(pos + 9, "WEP", 3) == 0)
111 cred->encr_type = WPS_ENCR_WEP;
112 #endif /* CONFIG_TESTING_OPTIONS */
113 else if (os_strncmp(pos + 9, "TKIP", 4) == 0)
114 cred->encr_type = WPS_ENCR_TKIP;
115 else if (os_strncmp(pos + 9, "CCMP", 4) == 0)
116 cred->encr_type = WPS_ENCR_AES;
117 else {
118 wpa_printf(MSG_DEBUG, "EAP-WSC: Unknown new_encr");
119 return -1;
120 }
121
122 pos = os_strstr(params, "new_key=");
123 if (pos == NULL)
124 return 0;
125 pos += 8;
126 end = os_strchr(pos, ' ');
127 if (end == NULL)
128 len = os_strlen(pos);
129 else
130 len = end - pos;
131 if ((len & 1) || len > 2 * sizeof(cred->key) ||
132 hexstr2bin(pos, cred->key, len / 2)) {
133 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid new_key");
134 return -1;
135 }
136 cred->key_len = len / 2;
137
138 return 1;
139 }
140
141
eap_wsc_init(struct eap_sm * sm)142 static void * eap_wsc_init(struct eap_sm *sm)
143 {
144 struct eap_wsc_data *data;
145 const u8 *identity;
146 size_t identity_len;
147 int registrar;
148 struct wps_config cfg;
149 const char *pos, *end;
150 const char *phase1;
151 struct wps_context *wps;
152 struct wps_credential new_ap_settings;
153 int res;
154 int nfc = 0;
155 u8 pkhash[WPS_OOB_PUBKEY_HASH_LEN];
156
157 wps = sm->wps;
158 if (wps == NULL) {
159 wpa_printf(MSG_ERROR, "EAP-WSC: WPS context not available");
160 return NULL;
161 }
162
163 identity = eap_get_config_identity(sm, &identity_len);
164
165 if (identity && identity_len == WSC_ID_REGISTRAR_LEN &&
166 os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0)
167 registrar = 1; /* Supplicant is Registrar */
168 else if (identity && identity_len == WSC_ID_ENROLLEE_LEN &&
169 os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0)
170 registrar = 0; /* Supplicant is Enrollee */
171 else {
172 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
173 identity, identity_len);
174 return NULL;
175 }
176
177 data = os_zalloc(sizeof(*data));
178 if (data == NULL)
179 return NULL;
180 data->state = registrar ? MESG : WAIT_START;
181 data->registrar = registrar;
182 data->wps_ctx = wps;
183
184 os_memset(&cfg, 0, sizeof(cfg));
185 cfg.wps = wps;
186 cfg.registrar = registrar;
187
188 phase1 = eap_get_config_phase1(sm);
189 if (phase1 == NULL) {
190 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
191 "set");
192 os_free(data);
193 return NULL;
194 }
195
196 pos = os_strstr(phase1, "pin=");
197 if (pos) {
198 pos += 4;
199 cfg.pin = (const u8 *) pos;
200 while (*pos != '\0' && *pos != ' ')
201 pos++;
202 cfg.pin_len = pos - (const char *) cfg.pin;
203 if (cfg.pin_len == 6 &&
204 os_strncmp((const char *) cfg.pin, "nfc-pw", 6) == 0) {
205 cfg.pin = NULL;
206 cfg.pin_len = 0;
207 nfc = 1;
208 }
209 } else {
210 pos = os_strstr(phase1, "pbc=1");
211 if (pos)
212 cfg.pbc = 1;
213 }
214
215 pos = os_strstr(phase1, "dev_pw_id=");
216 if (pos) {
217 u16 id = atoi(pos + 10);
218 if (id == DEV_PW_NFC_CONNECTION_HANDOVER)
219 nfc = 1;
220 if (cfg.pin || id == DEV_PW_NFC_CONNECTION_HANDOVER)
221 cfg.dev_pw_id = id;
222 }
223
224 if (cfg.pin == NULL && !cfg.pbc && !nfc) {
225 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
226 "configuration data");
227 os_free(data);
228 return NULL;
229 }
230
231 pos = os_strstr(phase1, " pkhash=");
232 if (pos) {
233 size_t len;
234 pos += 8;
235 end = os_strchr(pos, ' ');
236 if (end)
237 len = end - pos;
238 else
239 len = os_strlen(pos);
240 if (len != 2 * WPS_OOB_PUBKEY_HASH_LEN ||
241 hexstr2bin(pos, pkhash, WPS_OOB_PUBKEY_HASH_LEN)) {
242 wpa_printf(MSG_INFO, "EAP-WSC: Invalid pkhash");
243 os_free(data);
244 return NULL;
245 }
246 cfg.peer_pubkey_hash = pkhash;
247 }
248
249 res = eap_wsc_new_ap_settings(&new_ap_settings, phase1);
250 if (res < 0) {
251 os_free(data);
252 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to parse new AP "
253 "settings");
254 return NULL;
255 }
256 if (res == 1) {
257 wpa_printf(MSG_DEBUG, "EAP-WSC: Provide new AP settings for "
258 "WPS");
259 cfg.new_ap_settings = &new_ap_settings;
260 }
261
262 data->wps = wps_init(&cfg);
263 if (data->wps == NULL) {
264 os_free(data);
265 wpa_printf(MSG_DEBUG, "EAP-WSC: wps_init failed");
266 return NULL;
267 }
268 res = eap_get_config_fragment_size(sm);
269 if (res > 0)
270 data->fragment_size = res;
271 else
272 data->fragment_size = WSC_FRAGMENT_SIZE;
273 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment size limit %u",
274 (unsigned int) data->fragment_size);
275
276 if (registrar && cfg.pin) {
277 wps_registrar_add_pin(data->wps_ctx->registrar, NULL, NULL,
278 cfg.pin, cfg.pin_len, 0);
279 }
280
281 /* Use reduced client timeout for WPS to avoid long wait */
282 if (sm->ClientTimeout > 30)
283 sm->ClientTimeout = 30;
284
285 return data;
286 }
287
288
eap_wsc_deinit(struct eap_sm * sm,void * priv)289 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
290 {
291 struct eap_wsc_data *data = priv;
292 wpabuf_free(data->in_buf);
293 wpabuf_free(data->out_buf);
294 wps_deinit(data->wps);
295 os_free(data->wps_ctx->network_key);
296 data->wps_ctx->network_key = NULL;
297 os_free(data);
298 }
299
300
eap_wsc_build_msg(struct eap_wsc_data * data,struct eap_method_ret * ret,u8 id)301 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
302 struct eap_method_ret *ret, u8 id)
303 {
304 struct wpabuf *resp;
305 u8 flags;
306 size_t send_len, plen;
307
308 ret->ignore = FALSE;
309 wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
310 ret->allowNotifications = TRUE;
311
312 flags = 0;
313 send_len = wpabuf_len(data->out_buf) - data->out_used;
314 if (2 + send_len > data->fragment_size) {
315 send_len = data->fragment_size - 2;
316 flags |= WSC_FLAGS_MF;
317 if (data->out_used == 0) {
318 flags |= WSC_FLAGS_LF;
319 send_len -= 2;
320 }
321 }
322 plen = 2 + send_len;
323 if (flags & WSC_FLAGS_LF)
324 plen += 2;
325 resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
326 EAP_CODE_RESPONSE, id);
327 if (resp == NULL)
328 return NULL;
329
330 wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
331 wpabuf_put_u8(resp, flags); /* Flags */
332 if (flags & WSC_FLAGS_LF)
333 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
334
335 wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
336 send_len);
337 data->out_used += send_len;
338
339 ret->methodState = METHOD_MAY_CONT;
340 ret->decision = DECISION_FAIL;
341
342 if (data->out_used == wpabuf_len(data->out_buf)) {
343 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
344 "(message sent completely)",
345 (unsigned long) send_len);
346 wpabuf_free(data->out_buf);
347 data->out_buf = NULL;
348 data->out_used = 0;
349 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
350 data->out_op_code == WSC_NACK ||
351 data->out_op_code == WSC_Done) {
352 eap_wsc_state(data, FAIL);
353 ret->methodState = METHOD_DONE;
354 } else
355 eap_wsc_state(data, MESG);
356 } else {
357 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
358 "(%lu more to send)", (unsigned long) send_len,
359 (unsigned long) wpabuf_len(data->out_buf) -
360 data->out_used);
361 eap_wsc_state(data, WAIT_FRAG_ACK);
362 }
363
364 return resp;
365 }
366
367
eap_wsc_process_cont(struct eap_wsc_data * data,const u8 * buf,size_t len,u8 op_code)368 static int eap_wsc_process_cont(struct eap_wsc_data *data,
369 const u8 *buf, size_t len, u8 op_code)
370 {
371 /* Process continuation of a pending message */
372 if (op_code != data->in_op_code) {
373 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
374 "fragment (expected %d)",
375 op_code, data->in_op_code);
376 return -1;
377 }
378
379 if (len > wpabuf_tailroom(data->in_buf)) {
380 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
381 eap_wsc_state(data, FAIL);
382 return -1;
383 }
384
385 wpabuf_put_data(data->in_buf, buf, len);
386 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
387 "for %lu bytes more", (unsigned long) len,
388 (unsigned long) wpabuf_tailroom(data->in_buf));
389
390 return 0;
391 }
392
393
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)394 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
395 struct eap_method_ret *ret,
396 u8 id, u8 flags, u8 op_code,
397 u16 message_length,
398 const u8 *buf, size_t len)
399 {
400 /* Process a fragment that is not the last one of the message */
401 if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
402 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
403 "fragmented packet");
404 ret->ignore = TRUE;
405 return NULL;
406 }
407
408 if (data->in_buf == NULL) {
409 /* First fragment of the message */
410 data->in_buf = wpabuf_alloc(message_length);
411 if (data->in_buf == NULL) {
412 wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
413 "message");
414 ret->ignore = TRUE;
415 return NULL;
416 }
417 data->in_op_code = op_code;
418 wpabuf_put_data(data->in_buf, buf, len);
419 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
420 "fragment, waiting for %lu bytes more",
421 (unsigned long) len,
422 (unsigned long) wpabuf_tailroom(data->in_buf));
423 }
424
425 return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
426 }
427
428
eap_wsc_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)429 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
430 struct eap_method_ret *ret,
431 const struct wpabuf *reqData)
432 {
433 struct eap_wsc_data *data = priv;
434 const u8 *start, *pos, *end;
435 size_t len;
436 u8 op_code, flags, id;
437 u16 message_length = 0;
438 enum wps_process_res res;
439 struct wpabuf tmpbuf;
440 struct wpabuf *r;
441
442 pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
443 &len);
444 if (pos == NULL || len < 2) {
445 ret->ignore = TRUE;
446 return NULL;
447 }
448
449 id = eap_get_id(reqData);
450
451 start = pos;
452 end = start + len;
453
454 op_code = *pos++;
455 flags = *pos++;
456 if (flags & WSC_FLAGS_LF) {
457 if (end - pos < 2) {
458 wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
459 ret->ignore = TRUE;
460 return NULL;
461 }
462 message_length = WPA_GET_BE16(pos);
463 pos += 2;
464
465 if (message_length < end - pos || message_length > 50000) {
466 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
467 "Length");
468 ret->ignore = TRUE;
469 return NULL;
470 }
471 }
472
473 wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
474 "Flags 0x%x Message Length %d",
475 op_code, flags, message_length);
476
477 if (data->state == WAIT_FRAG_ACK) {
478 if (op_code != WSC_FRAG_ACK) {
479 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
480 "in WAIT_FRAG_ACK state", op_code);
481 ret->ignore = TRUE;
482 return NULL;
483 }
484 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
485 eap_wsc_state(data, MESG);
486 return eap_wsc_build_msg(data, ret, id);
487 }
488
489 if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
490 op_code != WSC_Done && op_code != WSC_Start) {
491 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
492 op_code);
493 ret->ignore = TRUE;
494 return NULL;
495 }
496
497 if (data->state == WAIT_START) {
498 if (op_code != WSC_Start) {
499 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
500 "in WAIT_START state", op_code);
501 ret->ignore = TRUE;
502 return NULL;
503 }
504 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
505 eap_wsc_state(data, MESG);
506 /* Start message has empty payload, skip processing */
507 goto send_msg;
508 } else if (op_code == WSC_Start) {
509 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
510 op_code);
511 ret->ignore = TRUE;
512 return NULL;
513 }
514
515 if (data->in_buf &&
516 eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
517 ret->ignore = TRUE;
518 return NULL;
519 }
520
521 if (flags & WSC_FLAGS_MF) {
522 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
523 message_length, pos,
524 end - pos);
525 }
526
527 if (data->in_buf == NULL) {
528 /* Wrap unfragmented messages as wpabuf without extra copy */
529 wpabuf_set(&tmpbuf, pos, end - pos);
530 data->in_buf = &tmpbuf;
531 }
532
533 res = wps_process_msg(data->wps, op_code, data->in_buf);
534 switch (res) {
535 case WPS_DONE:
536 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
537 "successfully - wait for EAP failure");
538 eap_wsc_state(data, FAIL);
539 break;
540 case WPS_CONTINUE:
541 eap_wsc_state(data, MESG);
542 break;
543 case WPS_FAILURE:
544 case WPS_PENDING:
545 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
546 eap_wsc_state(data, FAIL);
547 break;
548 }
549
550 if (data->in_buf != &tmpbuf)
551 wpabuf_free(data->in_buf);
552 data->in_buf = NULL;
553
554 send_msg:
555 if (data->out_buf == NULL) {
556 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
557 if (data->out_buf == NULL) {
558 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
559 "message from WPS");
560 return NULL;
561 }
562 data->out_used = 0;
563 }
564
565 eap_wsc_state(data, MESG);
566 r = eap_wsc_build_msg(data, ret, id);
567 if (data->state == FAIL && ret->methodState == METHOD_DONE) {
568 /* Use reduced client timeout for WPS to avoid long wait */
569 if (sm->ClientTimeout > 2)
570 sm->ClientTimeout = 2;
571 }
572 return r;
573 }
574
575
eap_peer_wsc_register(void)576 int eap_peer_wsc_register(void)
577 {
578 struct eap_method *eap;
579 int ret;
580
581 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
582 EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
583 "WSC");
584 if (eap == NULL)
585 return -1;
586
587 eap->init = eap_wsc_init;
588 eap->deinit = eap_wsc_deinit;
589 eap->process = eap_wsc_process;
590
591 ret = eap_peer_method_register(eap);
592 if (ret)
593 eap_peer_method_free(eap);
594 return ret;
595 }
596