1 /*
2 * EAP-WSC peer for Wi-Fi Protected Setup
3 * Copyright (c) 2007-2009, 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 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
eap_wsc_init(struct eap_sm * sm)128 static 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
141 wps = sm->wps;
142 if (wps == NULL) {
143 wpa_printf(MSG_ERROR, "EAP-WSC: WPS context not available");
144 return NULL;
145 }
146
147 identity = eap_get_config_identity(sm, &identity_len);
148
149 if (identity && identity_len == WSC_ID_REGISTRAR_LEN &&
150 os_memcmp(identity, WSC_ID_REGISTRAR, WSC_ID_REGISTRAR_LEN) == 0)
151 registrar = 1; /* Supplicant is Registrar */
152 else if (identity && identity_len == WSC_ID_ENROLLEE_LEN &&
153 os_memcmp(identity, WSC_ID_ENROLLEE, WSC_ID_ENROLLEE_LEN) == 0)
154 registrar = 0; /* Supplicant is Enrollee */
155 else {
156 wpa_hexdump_ascii(MSG_INFO, "EAP-WSC: Unexpected identity",
157 identity, identity_len);
158 return NULL;
159 }
160
161 data = os_zalloc(sizeof(*data));
162 if (data == NULL)
163 return NULL;
164 data->state = registrar ? MESG : WAIT_START;
165 data->registrar = registrar;
166 data->wps_ctx = wps;
167
168 os_memset(&cfg, 0, sizeof(cfg));
169 cfg.wps = wps;
170 cfg.registrar = registrar;
171
172 phase1 = eap_get_config_phase1(sm);
173 if (phase1 == NULL) {
174 wpa_printf(MSG_INFO, "EAP-WSC: phase1 configuration data not "
175 "set");
176 os_free(data);
177 return NULL;
178 }
179
180 pos = os_strstr(phase1, "pin=");
181 if (pos) {
182 pos += 4;
183 cfg.pin = (const u8 *) pos;
184 while (*pos != '\0' && *pos != ' ')
185 pos++;
186 cfg.pin_len = pos - (const char *) cfg.pin;
187 } else {
188 pos = os_strstr(phase1, "pbc=1");
189 if (pos)
190 cfg.pbc = 1;
191 }
192
193 if (cfg.pin == NULL && !cfg.pbc) {
194 wpa_printf(MSG_INFO, "EAP-WSC: PIN or PBC not set in phase1 "
195 "configuration data");
196 os_free(data);
197 return NULL;
198 }
199
200 pos = os_strstr(phase1, "dev_pw_id=");
201 if (pos && cfg.pin)
202 cfg.dev_pw_id = atoi(pos + 10);
203
204 res = eap_wsc_new_ap_settings(&new_ap_settings, phase1);
205 if (res < 0) {
206 os_free(data);
207 return NULL;
208 }
209 if (res == 1) {
210 wpa_printf(MSG_DEBUG, "EAP-WSC: Provide new AP settings for "
211 "WPS");
212 cfg.new_ap_settings = &new_ap_settings;
213 }
214
215 data->wps = wps_init(&cfg);
216 if (data->wps == NULL) {
217 os_free(data);
218 return NULL;
219 }
220 res = eap_get_config_fragment_size(sm);
221 if (res > 0)
222 data->fragment_size = res;
223 else
224 data->fragment_size = WSC_FRAGMENT_SIZE;
225 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment size limit %u",
226 (unsigned int) data->fragment_size);
227
228 if (registrar && cfg.pin) {
229 wps_registrar_add_pin(data->wps_ctx->registrar, NULL, NULL,
230 cfg.pin, cfg.pin_len, 0);
231 }
232
233 /* Use reduced client timeout for WPS to avoid long wait */
234 if (sm->ClientTimeout > 30)
235 sm->ClientTimeout = 30;
236
237 return data;
238 }
239
240
eap_wsc_deinit(struct eap_sm * sm,void * priv)241 static void eap_wsc_deinit(struct eap_sm *sm, void *priv)
242 {
243 struct eap_wsc_data *data = priv;
244 wpabuf_free(data->in_buf);
245 wpabuf_free(data->out_buf);
246 wps_deinit(data->wps);
247 os_free(data->wps_ctx->network_key);
248 data->wps_ctx->network_key = NULL;
249 os_free(data);
250 }
251
252
eap_wsc_build_msg(struct eap_wsc_data * data,struct eap_method_ret * ret,u8 id)253 static struct wpabuf * eap_wsc_build_msg(struct eap_wsc_data *data,
254 struct eap_method_ret *ret, u8 id)
255 {
256 struct wpabuf *resp;
257 u8 flags;
258 size_t send_len, plen;
259
260 ret->ignore = FALSE;
261 wpa_printf(MSG_DEBUG, "EAP-WSC: Generating Response");
262 ret->allowNotifications = TRUE;
263
264 flags = 0;
265 send_len = wpabuf_len(data->out_buf) - data->out_used;
266 if (2 + send_len > data->fragment_size) {
267 send_len = data->fragment_size - 2;
268 flags |= WSC_FLAGS_MF;
269 if (data->out_used == 0) {
270 flags |= WSC_FLAGS_LF;
271 send_len -= 2;
272 }
273 }
274 plen = 2 + send_len;
275 if (flags & WSC_FLAGS_LF)
276 plen += 2;
277 resp = eap_msg_alloc(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, plen,
278 EAP_CODE_RESPONSE, id);
279 if (resp == NULL)
280 return NULL;
281
282 wpabuf_put_u8(resp, data->out_op_code); /* Op-Code */
283 wpabuf_put_u8(resp, flags); /* Flags */
284 if (flags & WSC_FLAGS_LF)
285 wpabuf_put_be16(resp, wpabuf_len(data->out_buf));
286
287 wpabuf_put_data(resp, wpabuf_head_u8(data->out_buf) + data->out_used,
288 send_len);
289 data->out_used += send_len;
290
291 ret->methodState = METHOD_MAY_CONT;
292 ret->decision = DECISION_FAIL;
293
294 if (data->out_used == wpabuf_len(data->out_buf)) {
295 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
296 "(message sent completely)",
297 (unsigned long) send_len);
298 wpabuf_free(data->out_buf);
299 data->out_buf = NULL;
300 data->out_used = 0;
301 if ((data->state == FAIL && data->out_op_code == WSC_ACK) ||
302 data->out_op_code == WSC_NACK ||
303 data->out_op_code == WSC_Done) {
304 eap_wsc_state(data, FAIL);
305 ret->methodState = METHOD_DONE;
306 } else
307 eap_wsc_state(data, MESG);
308 } else {
309 wpa_printf(MSG_DEBUG, "EAP-WSC: Sending out %lu bytes "
310 "(%lu more to send)", (unsigned long) send_len,
311 (unsigned long) wpabuf_len(data->out_buf) -
312 data->out_used);
313 eap_wsc_state(data, WAIT_FRAG_ACK);
314 }
315
316 return resp;
317 }
318
319
eap_wsc_process_cont(struct eap_wsc_data * data,const u8 * buf,size_t len,u8 op_code)320 static int eap_wsc_process_cont(struct eap_wsc_data *data,
321 const u8 *buf, size_t len, u8 op_code)
322 {
323 /* Process continuation of a pending message */
324 if (op_code != data->in_op_code) {
325 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d in "
326 "fragment (expected %d)",
327 op_code, data->in_op_code);
328 return -1;
329 }
330
331 if (len > wpabuf_tailroom(data->in_buf)) {
332 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment overflow");
333 eap_wsc_state(data, FAIL);
334 return -1;
335 }
336
337 wpabuf_put_data(data->in_buf, buf, len);
338 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes, waiting "
339 "for %lu bytes more", (unsigned long) len,
340 (unsigned long) wpabuf_tailroom(data->in_buf));
341
342 return 0;
343 }
344
345
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)346 static struct wpabuf * eap_wsc_process_fragment(struct eap_wsc_data *data,
347 struct eap_method_ret *ret,
348 u8 id, u8 flags, u8 op_code,
349 u16 message_length,
350 const u8 *buf, size_t len)
351 {
352 /* Process a fragment that is not the last one of the message */
353 if (data->in_buf == NULL && !(flags & WSC_FLAGS_LF)) {
354 wpa_printf(MSG_DEBUG, "EAP-WSC: No Message Length field in a "
355 "fragmented packet");
356 ret->ignore = TRUE;
357 return NULL;
358 }
359
360 if (data->in_buf == NULL) {
361 /* First fragment of the message */
362 data->in_buf = wpabuf_alloc(message_length);
363 if (data->in_buf == NULL) {
364 wpa_printf(MSG_DEBUG, "EAP-WSC: No memory for "
365 "message");
366 ret->ignore = TRUE;
367 return NULL;
368 }
369 data->in_op_code = op_code;
370 wpabuf_put_data(data->in_buf, buf, len);
371 wpa_printf(MSG_DEBUG, "EAP-WSC: Received %lu bytes in first "
372 "fragment, waiting for %lu bytes more",
373 (unsigned long) len,
374 (unsigned long) wpabuf_tailroom(data->in_buf));
375 }
376
377 return eap_wsc_build_frag_ack(id, EAP_CODE_RESPONSE);
378 }
379
380
eap_wsc_process(struct eap_sm * sm,void * priv,struct eap_method_ret * ret,const struct wpabuf * reqData)381 static struct wpabuf * eap_wsc_process(struct eap_sm *sm, void *priv,
382 struct eap_method_ret *ret,
383 const struct wpabuf *reqData)
384 {
385 struct eap_wsc_data *data = priv;
386 const u8 *start, *pos, *end;
387 size_t len;
388 u8 op_code, flags, id;
389 u16 message_length = 0;
390 enum wps_process_res res;
391 struct wpabuf tmpbuf;
392 struct wpabuf *r;
393
394 pos = eap_hdr_validate(EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC, reqData,
395 &len);
396 if (pos == NULL || len < 2) {
397 ret->ignore = TRUE;
398 return NULL;
399 }
400
401 id = eap_get_id(reqData);
402
403 start = pos;
404 end = start + len;
405
406 op_code = *pos++;
407 flags = *pos++;
408 if (flags & WSC_FLAGS_LF) {
409 if (end - pos < 2) {
410 wpa_printf(MSG_DEBUG, "EAP-WSC: Message underflow");
411 ret->ignore = TRUE;
412 return NULL;
413 }
414 message_length = WPA_GET_BE16(pos);
415 pos += 2;
416
417 if (message_length < end - pos) {
418 wpa_printf(MSG_DEBUG, "EAP-WSC: Invalid Message "
419 "Length");
420 ret->ignore = TRUE;
421 return NULL;
422 }
423 }
424
425 wpa_printf(MSG_DEBUG, "EAP-WSC: Received packet: Op-Code %d "
426 "Flags 0x%x Message Length %d",
427 op_code, flags, message_length);
428
429 if (data->state == WAIT_FRAG_ACK) {
430 if (op_code != WSC_FRAG_ACK) {
431 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
432 "in WAIT_FRAG_ACK state", op_code);
433 ret->ignore = TRUE;
434 return NULL;
435 }
436 wpa_printf(MSG_DEBUG, "EAP-WSC: Fragment acknowledged");
437 eap_wsc_state(data, MESG);
438 return eap_wsc_build_msg(data, ret, id);
439 }
440
441 if (op_code != WSC_ACK && op_code != WSC_NACK && op_code != WSC_MSG &&
442 op_code != WSC_Done && op_code != WSC_Start) {
443 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
444 op_code);
445 ret->ignore = TRUE;
446 return NULL;
447 }
448
449 if (data->state == WAIT_START) {
450 if (op_code != WSC_Start) {
451 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d "
452 "in WAIT_START state", op_code);
453 ret->ignore = TRUE;
454 return NULL;
455 }
456 wpa_printf(MSG_DEBUG, "EAP-WSC: Received start");
457 eap_wsc_state(data, MESG);
458 /* Start message has empty payload, skip processing */
459 goto send_msg;
460 } else if (op_code == WSC_Start) {
461 wpa_printf(MSG_DEBUG, "EAP-WSC: Unexpected Op-Code %d",
462 op_code);
463 ret->ignore = TRUE;
464 return NULL;
465 }
466
467 if (data->in_buf &&
468 eap_wsc_process_cont(data, pos, end - pos, op_code) < 0) {
469 ret->ignore = TRUE;
470 return NULL;
471 }
472
473 if (flags & WSC_FLAGS_MF) {
474 return eap_wsc_process_fragment(data, ret, id, flags, op_code,
475 message_length, pos,
476 end - pos);
477 }
478
479 if (data->in_buf == NULL) {
480 /* Wrap unfragmented messages as wpabuf without extra copy */
481 wpabuf_set(&tmpbuf, pos, end - pos);
482 data->in_buf = &tmpbuf;
483 }
484
485 res = wps_process_msg(data->wps, op_code, data->in_buf);
486 switch (res) {
487 case WPS_DONE:
488 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing completed "
489 "successfully - wait for EAP failure");
490 eap_wsc_state(data, FAIL);
491 break;
492 case WPS_CONTINUE:
493 eap_wsc_state(data, MESG);
494 break;
495 case WPS_FAILURE:
496 case WPS_PENDING:
497 wpa_printf(MSG_DEBUG, "EAP-WSC: WPS processing failed");
498 eap_wsc_state(data, FAIL);
499 break;
500 }
501
502 if (data->in_buf != &tmpbuf)
503 wpabuf_free(data->in_buf);
504 data->in_buf = NULL;
505
506 send_msg:
507 if (data->out_buf == NULL) {
508 data->out_buf = wps_get_msg(data->wps, &data->out_op_code);
509 if (data->out_buf == NULL) {
510 wpa_printf(MSG_DEBUG, "EAP-WSC: Failed to receive "
511 "message from WPS");
512 return NULL;
513 }
514 data->out_used = 0;
515 }
516
517 eap_wsc_state(data, MESG);
518 r = eap_wsc_build_msg(data, ret, id);
519 if (data->state == FAIL && ret->methodState == METHOD_DONE) {
520 /* Use reduced client timeout for WPS to avoid long wait */
521 if (sm->ClientTimeout > 2)
522 sm->ClientTimeout = 2;
523 }
524 return r;
525 }
526
527
eap_peer_wsc_register(void)528 int eap_peer_wsc_register(void)
529 {
530 struct eap_method *eap;
531 int ret;
532
533 eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
534 EAP_VENDOR_WFA, EAP_VENDOR_TYPE_WSC,
535 "WSC");
536 if (eap == NULL)
537 return -1;
538
539 eap->init = eap_wsc_init;
540 eap->deinit = eap_wsc_deinit;
541 eap->process = eap_wsc_process;
542
543 ret = eap_peer_method_register(eap);
544 if (ret)
545 eap_peer_method_free(eap);
546 return ret;
547 }
548