eap_wsc.c revision 04949598a23f501be6eec21697465fd46a28840a
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
19struct 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
32static 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
53static 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
62static 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		return -1;
82	cred->ssid_len = len / 2;
83
84	pos = os_strstr(params, "new_auth=");
85	if (pos == NULL)
86		return -1;
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		return -1;
95
96	pos = os_strstr(params, "new_encr=");
97	if (pos == NULL)
98		return -1;
99	if (os_strncmp(pos + 9, "NONE", 4) == 0)
100		cred->encr_type = WPS_ENCR_NONE;
101	else if (os_strncmp(pos + 9, "WEP", 3) == 0)
102		cred->encr_type = WPS_ENCR_WEP;
103	else if (os_strncmp(pos + 9, "TKIP", 4) == 0)
104		cred->encr_type = WPS_ENCR_TKIP;
105	else if (os_strncmp(pos + 9, "CCMP", 4) == 0)
106		cred->encr_type = WPS_ENCR_AES;
107	else
108		return -1;
109
110	pos = os_strstr(params, "new_key=");
111	if (pos == NULL)
112		return 0;
113	pos += 8;
114	end = os_strchr(pos, ' ');
115	if (end == NULL)
116		len = os_strlen(pos);
117	else
118		len = end - pos;
119	if ((len & 1) || len > 2 * sizeof(cred->key) ||
120	    hexstr2bin(pos, cred->key, len / 2))
121		return -1;
122	cred->key_len = len / 2;
123
124	return 1;
125}
126
127
128static void * eap_wsc_init(struct eap_sm *sm)
129{
130	struct eap_wsc_data *data;
131	const u8 *identity;
132	size_t identity_len;
133	int registrar;
134	struct wps_config cfg;
135	const char *pos;
136	const char *phase1;
137	struct wps_context *wps;
138	struct wps_credential new_ap_settings;
139	int res;
140	u8 dev_pw[WPS_OOB_DEVICE_PASSWORD_LEN];
141	int nfc = 0;
142
143	wps = sm->wps;
144	if (wps == NULL) {
145		wpa_printf(MSG_ERROR, "EAP-WSC: WPS context not available");
146		return NULL;
147	}
148
149	identity = eap_get_config_identity(sm, &identity_len);
150
151	if (identity && identity_len == WSC_ID_REGISTRAR_LEN &&
152	    os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0)
153		registrar = 1; /* Supplicant is Registrar */
154	else if (identity && identity_len == WSC_ID_ENROLLEE_LEN &&
155	    os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0)
156		registrar = 0; /* Supplicant is Enrollee */
157	else {
158		wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
159				  identity, identity_len);
160		return NULL;
161	}
162
163	data = os_zalloc(sizeof(*data));
164	if (data == NULL)
165		return NULL;
166	data->state = registrar ? MESG : WAIT_START;
167	data->registrar = registrar;
168	data->wps_ctx = wps;
169
170	os_memset(&cfg, 0, sizeof(cfg));
171	cfg.wps = wps;
172	cfg.registrar = registrar;
173
174	phase1 = eap_get_config_phase1(sm);
175	if (phase1 == NULL) {
176		wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
177			   "set");
178		os_free(data);
179		return NULL;
180	}
181
182	pos = os_strstr(phase1, "pin=");
183	if (pos) {
184		pos += 4;
185		cfg.pin = (const u8 *) pos;
186		while (*pos != '\0' && *pos != ' ')
187			pos++;
188		cfg.pin_len = pos - (const char *) cfg.pin;
189		if (cfg.pin_len >= WPS_OOB_DEVICE_PASSWORD_MIN_LEN * 2 &&
190		    cfg.pin_len <= WPS_OOB_DEVICE_PASSWORD_LEN * 2 &&
191		    hexstr2bin((const char *) cfg.pin, dev_pw,
192			       cfg.pin_len / 2) == 0) {
193			/* Convert OOB Device Password to binary */
194			cfg.pin = dev_pw;
195			cfg.pin_len /= 2;
196		}
197		if (cfg.pin_len == 6 && os_strncmp(pos, "nfc-pw", 6) == 0) {
198			cfg.pin = NULL;
199			cfg.pin_len = 0;
200			nfc = 1;
201		}
202	} else {
203		pos = os_strstr(phase1, "pbc=1");
204		if (pos)
205			cfg.pbc = 1;
206	}
207
208	if (cfg.pin == NULL && !cfg.pbc && !nfc) {
209		wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
210			   "configuration data");
211		os_free(data);
212		return NULL;
213	}
214
215	pos = os_strstr(phase1, "dev_pw_id=");
216	if (pos && cfg.pin)
217		cfg.dev_pw_id = atoi(pos + 10);
218
219	res = eap_wsc_new_ap_settings(&new_ap_settings, phase1);
220	if (res < 0) {
221		os_free(data);
222		return NULL;
223	}
224	if (res == 1) {
225		wpa_printf(MSG_DEBUG, "EAP-WSC: Provide new AP settings for "
226			   "WPS");
227		cfg.new_ap_settings = &new_ap_settings;
228	}
229
230	data->wps = wps_init(&cfg);
231	if (data->wps == NULL) {
232		os_free(data);
233		return NULL;
234	}
235	res = eap_get_config_fragment_size(sm);
236	if (res > 0)
237		data->fragment_size = res;
238	else
239		data->fragment_size = WSC_FRAGMENT_SIZE;
240	wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment size limit %u",
241		   (unsigned int) data->fragment_size);
242
243	if (registrar && cfg.pin) {
244		wps_registrar_add_pin(data->wps_ctx->registrar, NULL, NULL,
245				      cfg.pin, cfg.pin_len, 0);
246	}
247
248	/* Use reduced client timeout for WPS to avoid long wait */
249	if (sm->ClientTimeout > 30)
250		sm->ClientTimeout = 30;
251
252	return data;
253}
254
255
256static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
257{
258	struct eap_wsc_data *data = priv;
259	wpabuf_free(data->in_buf);
260	wpabuf_free(data->out_buf);
261	wps_deinit(data->wps);
262	os_free(data->wps_ctx->network_key);
263	data->wps_ctx->network_key = NULL;
264	os_free(data);
265}
266
267
268static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
269					 struct eap_method_ret *ret, u8 id)
270{
271	struct wpabuf *resp;
272	u8 flags;
273	size_t send_len, plen;
274
275	ret->ignore = FALSE;
276	wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
277	ret->allowNotifications = TRUE;
278
279	flags = 0;
280	send_len = wpabuf_len(data->out_buf) - data->out_used;
281	if (2 + send_len > data->fragment_size) {
282		send_len = data->fragment_size - 2;
283		flags |= WSC_FLAGS_MF;
284		if (data->out_used == 0) {
285			flags |= WSC_FLAGS_LF;
286			send_len -= 2;
287		}
288	}
289	plen = 2 + send_len;
290	if (flags & WSC_FLAGS_LF)
291		plen += 2;
292	resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
293			     EAP_CODE_RESPONSE, id);
294	if (resp == NULL)
295		return NULL;
296
297	wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
298	wpabuf_put_u8(resp, flags); /* Flags */
299	if (flags & WSC_FLAGS_LF)
300		wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
301
302	wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
303			send_len);
304	data->out_used += send_len;
305
306	ret->methodState = METHOD_MAY_CONT;
307	ret->decision = DECISION_FAIL;
308
309	if (data->out_used == wpabuf_len(data->out_buf)) {
310		wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
311			   "(message sent completely)",
312			   (unsigned long) send_len);
313		wpabuf_free(data->out_buf);
314		data->out_buf = NULL;
315		data->out_used = 0;
316		if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
317		    data->out_op_code == WSC_NACK ||
318		    data->out_op_code == WSC_Done) {
319			eap_wsc_state(data, FAIL);
320			ret->methodState = METHOD_DONE;
321		} else
322			eap_wsc_state(data, MESG);
323	} else {
324		wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
325			   "(%lu more to send)", (unsigned long) send_len,
326			   (unsigned long) wpabuf_len(data->out_buf) -
327			   data->out_used);
328		eap_wsc_state(data, WAIT_FRAG_ACK);
329	}
330
331	return resp;
332}
333
334
335static int eap_wsc_process_cont(struct eap_wsc_data *data,
336				const u8 *buf, size_t len, u8 op_code)
337{
338	/* Process continuation of a pending message */
339	if (op_code != data->in_op_code) {
340		wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
341			   "fragment (expected %d)",
342			   op_code, data->in_op_code);
343		return -1;
344	}
345
346	if (len > wpabuf_tailroom(data->in_buf)) {
347		wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
348		eap_wsc_state(data, FAIL);
349		return -1;
350	}
351
352	wpabuf_put_data(data->in_buf, buf, len);
353	wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
354		   "for %lu bytes more", (unsigned long) len,
355		   (unsigned long) wpabuf_tailroom(data->in_buf));
356
357	return 0;
358}
359
360
361static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
362						struct eap_method_ret *ret,
363						u8 id, u8 flags, u8 op_code,
364						u16 message_length,
365						const u8 *buf, size_t len)
366{
367	/* Process a fragment that is not the last one of the message */
368	if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
369		wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
370			   "fragmented packet");
371		ret->ignore = TRUE;
372		return NULL;
373	}
374
375	if (data->in_buf == NULL) {
376		/* First fragment of the message */
377		data->in_buf = wpabuf_alloc(message_length);
378		if (data->in_buf == NULL) {
379			wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
380				   "message");
381			ret->ignore = TRUE;
382			return NULL;
383		}
384		data->in_op_code = op_code;
385		wpabuf_put_data(data->in_buf, buf, len);
386		wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
387			   "fragment, waiting for %lu bytes more",
388			   (unsigned long) len,
389			   (unsigned long) wpabuf_tailroom(data->in_buf));
390	}
391
392	return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
393}
394
395
396static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
397				       struct eap_method_ret *ret,
398				       const struct wpabuf *reqData)
399{
400	struct eap_wsc_data *data = priv;
401	const u8 *start, *pos, *end;
402	size_t len;
403	u8 op_code, flags, id;
404	u16 message_length = 0;
405	enum wps_process_res res;
406	struct wpabuf tmpbuf;
407	struct wpabuf *r;
408
409	pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
410			       &len);
411	if (pos == NULL || len < 2) {
412		ret->ignore = TRUE;
413		return NULL;
414	}
415
416	id = eap_get_id(reqData);
417
418	start = pos;
419	end = start + len;
420
421	op_code = *pos++;
422	flags = *pos++;
423	if (flags & WSC_FLAGS_LF) {
424		if (end - pos < 2) {
425			wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
426			ret->ignore = TRUE;
427			return NULL;
428		}
429		message_length = WPA_GET_BE16(pos);
430		pos += 2;
431
432		if (message_length < end - pos) {
433			wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
434				   "Length");
435			ret->ignore = TRUE;
436			return NULL;
437		}
438	}
439
440	wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
441		   "Flags 0x%x Message Length %d",
442		   op_code, flags, message_length);
443
444	if (data->state == WAIT_FRAG_ACK) {
445		if (op_code != WSC_FRAG_ACK) {
446			wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
447				   "in WAIT_FRAG_ACK state", op_code);
448			ret->ignore = TRUE;
449			return NULL;
450		}
451		wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
452		eap_wsc_state(data, MESG);
453		return eap_wsc_build_msg(data, ret, id);
454	}
455
456	if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
457	    op_code != WSC_Done && op_code != WSC_Start) {
458		wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
459			   op_code);
460		ret->ignore = TRUE;
461		return NULL;
462	}
463
464	if (data->state == WAIT_START) {
465		if (op_code != WSC_Start) {
466			wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
467				   "in WAIT_START state", op_code);
468			ret->ignore = TRUE;
469			return NULL;
470		}
471		wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
472		eap_wsc_state(data, MESG);
473		/* Start message has empty payload, skip processing */
474		goto send_msg;
475	} else if (op_code == WSC_Start) {
476		wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
477			   op_code);
478		ret->ignore = TRUE;
479		return NULL;
480	}
481
482	if (data->in_buf &&
483	    eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
484		ret->ignore = TRUE;
485		return NULL;
486	}
487
488	if (flags & WSC_FLAGS_MF) {
489		return eap_wsc_process_fragment(data, ret, id, flags, op_code,
490						message_length, pos,
491						end - pos);
492	}
493
494	if (data->in_buf == NULL) {
495		/* Wrap unfragmented messages as wpabuf without extra copy */
496		wpabuf_set(&tmpbuf, pos, end - pos);
497		data->in_buf = &tmpbuf;
498	}
499
500	res = wps_process_msg(data->wps, op_code, data->in_buf);
501	switch (res) {
502	case WPS_DONE:
503		wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
504			   "successfully - wait for EAP failure");
505		eap_wsc_state(data, FAIL);
506		break;
507	case WPS_CONTINUE:
508		eap_wsc_state(data, MESG);
509		break;
510	case WPS_FAILURE:
511	case WPS_PENDING:
512		wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
513		eap_wsc_state(data, FAIL);
514		break;
515	}
516
517	if (data->in_buf != &tmpbuf)
518		wpabuf_free(data->in_buf);
519	data->in_buf = NULL;
520
521send_msg:
522	if (data->out_buf == NULL) {
523		data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
524		if (data->out_buf == NULL) {
525			wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
526				   "message from WPS");
527			return NULL;
528		}
529		data->out_used = 0;
530	}
531
532	eap_wsc_state(data, MESG);
533	r = eap_wsc_build_msg(data, ret, id);
534	if (data->state == FAIL && ret->methodState == METHOD_DONE) {
535		/* Use reduced client timeout for WPS to avoid long wait */
536		if (sm->ClientTimeout > 2)
537			sm->ClientTimeout = 2;
538	}
539	return r;
540}
541
542
543int eap_peer_wsc_register(void)
544{
545	struct eap_method *eap;
546	int ret;
547
548	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
549				    EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
550				    "WSC");
551	if (eap == NULL)
552		return -1;
553
554	eap->init = eap_wsc_init;
555	eap->deinit = eap_wsc_deinit;
556	eap->process = eap_wsc_process;
557
558	ret = eap_peer_method_register(eap);
559	if (ret)
560		eap_peer_method_free(eap);
561	return ret;
562}
563