xref: /freebsd/contrib/wpa/src/radius/radius.c (revision 2b15cb3d0922bd70ea592f0da9b4a5b167f4d53f)
1 /*
2  * RADIUS message processing
3  * Copyright (c) 2002-2009, 2011-2012, 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 "utils/includes.h"
10 
11 #include "utils/common.h"
12 #include "utils/wpabuf.h"
13 #include "crypto/md5.h"
14 #include "crypto/crypto.h"
15 #include "radius.h"
16 
17 
18 /**
19  * struct radius_msg - RADIUS message structure for new and parsed messages
20  */
21 struct radius_msg {
22 	/**
23 	 * buf - Allocated buffer for RADIUS message
24 	 */
25 	struct wpabuf *buf;
26 
27 	/**
28 	 * hdr - Pointer to the RADIUS header in buf
29 	 */
30 	struct radius_hdr *hdr;
31 
32 	/**
33 	 * attr_pos - Array of indexes to attributes
34 	 *
35 	 * The values are number of bytes from buf to the beginning of
36 	 * struct radius_attr_hdr.
37 	 */
38 	size_t *attr_pos;
39 
40 	/**
41 	 * attr_size - Total size of the attribute pointer array
42 	 */
43 	size_t attr_size;
44 
45 	/**
46 	 * attr_used - Total number of attributes in the array
47 	 */
48 	size_t attr_used;
49 };
50 
51 
52 struct radius_hdr * radius_msg_get_hdr(struct radius_msg *msg)
53 {
54 	return msg->hdr;
55 }
56 
57 
58 struct wpabuf * radius_msg_get_buf(struct radius_msg *msg)
59 {
60 	return msg->buf;
61 }
62 
63 
64 static struct radius_attr_hdr *
65 radius_get_attr_hdr(struct radius_msg *msg, int idx)
66 {
67 	return (struct radius_attr_hdr *)
68 		(wpabuf_mhead_u8(msg->buf) + msg->attr_pos[idx]);
69 }
70 
71 
72 static void radius_msg_set_hdr(struct radius_msg *msg, u8 code, u8 identifier)
73 {
74 	msg->hdr->code = code;
75 	msg->hdr->identifier = identifier;
76 }
77 
78 
79 static int radius_msg_initialize(struct radius_msg *msg)
80 {
81 	msg->attr_pos = os_calloc(RADIUS_DEFAULT_ATTR_COUNT,
82 				  sizeof(*msg->attr_pos));
83 	if (msg->attr_pos == NULL)
84 		return -1;
85 
86 	msg->attr_size = RADIUS_DEFAULT_ATTR_COUNT;
87 	msg->attr_used = 0;
88 
89 	return 0;
90 }
91 
92 
93 /**
94  * radius_msg_new - Create a new RADIUS message
95  * @code: Code for RADIUS header
96  * @identifier: Identifier for RADIUS header
97  * Returns: Context for RADIUS message or %NULL on failure
98  *
99  * The caller is responsible for freeing the returned data with
100  * radius_msg_free().
101  */
102 struct radius_msg * radius_msg_new(u8 code, u8 identifier)
103 {
104 	struct radius_msg *msg;
105 
106 	msg = os_zalloc(sizeof(*msg));
107 	if (msg == NULL)
108 		return NULL;
109 
110 	msg->buf = wpabuf_alloc(RADIUS_DEFAULT_MSG_SIZE);
111 	if (msg->buf == NULL || radius_msg_initialize(msg)) {
112 		radius_msg_free(msg);
113 		return NULL;
114 	}
115 	msg->hdr = wpabuf_put(msg->buf, sizeof(struct radius_hdr));
116 
117 	radius_msg_set_hdr(msg, code, identifier);
118 
119 	return msg;
120 }
121 
122 
123 /**
124  * radius_msg_free - Free a RADIUS message
125  * @msg: RADIUS message from radius_msg_new() or radius_msg_parse()
126  */
127 void radius_msg_free(struct radius_msg *msg)
128 {
129 	if (msg == NULL)
130 		return;
131 
132 	wpabuf_free(msg->buf);
133 	os_free(msg->attr_pos);
134 	os_free(msg);
135 }
136 
137 
138 static const char *radius_code_string(u8 code)
139 {
140 	switch (code) {
141 	case RADIUS_CODE_ACCESS_REQUEST: return "Access-Request";
142 	case RADIUS_CODE_ACCESS_ACCEPT: return "Access-Accept";
143 	case RADIUS_CODE_ACCESS_REJECT: return "Access-Reject";
144 	case RADIUS_CODE_ACCOUNTING_REQUEST: return "Accounting-Request";
145 	case RADIUS_CODE_ACCOUNTING_RESPONSE: return "Accounting-Response";
146 	case RADIUS_CODE_ACCESS_CHALLENGE: return "Access-Challenge";
147 	case RADIUS_CODE_STATUS_SERVER: return "Status-Server";
148 	case RADIUS_CODE_STATUS_CLIENT: return "Status-Client";
149 	case RADIUS_CODE_RESERVED: return "Reserved";
150 	case RADIUS_CODE_DISCONNECT_REQUEST: return "Disconnect-Request";
151 	case RADIUS_CODE_DISCONNECT_ACK: return "Disconnect-ACK";
152 	case RADIUS_CODE_DISCONNECT_NAK: return "Disconnect-NAK";
153 	case RADIUS_CODE_COA_REQUEST: return "CoA-Request";
154 	case RADIUS_CODE_COA_ACK: return "CoA-ACK";
155 	case RADIUS_CODE_COA_NAK: return "CoA-NAK";
156 	default: return "?Unknown?";
157 	}
158 }
159 
160 
161 struct radius_attr_type {
162 	u8 type;
163 	char *name;
164 	enum {
165 		RADIUS_ATTR_UNDIST, RADIUS_ATTR_TEXT, RADIUS_ATTR_IP,
166 		RADIUS_ATTR_HEXDUMP, RADIUS_ATTR_INT32, RADIUS_ATTR_IPV6
167 	} data_type;
168 };
169 
170 static struct radius_attr_type radius_attrs[] =
171 {
172 	{ RADIUS_ATTR_USER_NAME, "User-Name", RADIUS_ATTR_TEXT },
173 	{ RADIUS_ATTR_USER_PASSWORD, "User-Password", RADIUS_ATTR_UNDIST },
174 	{ RADIUS_ATTR_NAS_IP_ADDRESS, "NAS-IP-Address", RADIUS_ATTR_IP },
175 	{ RADIUS_ATTR_NAS_PORT, "NAS-Port", RADIUS_ATTR_INT32 },
176 	{ RADIUS_ATTR_FRAMED_MTU, "Framed-MTU", RADIUS_ATTR_INT32 },
177 	{ RADIUS_ATTR_REPLY_MESSAGE, "Reply-Message", RADIUS_ATTR_TEXT },
178 	{ RADIUS_ATTR_STATE, "State", RADIUS_ATTR_UNDIST },
179 	{ RADIUS_ATTR_CLASS, "Class", RADIUS_ATTR_UNDIST },
180 	{ RADIUS_ATTR_VENDOR_SPECIFIC, "Vendor-Specific", RADIUS_ATTR_UNDIST },
181 	{ RADIUS_ATTR_SESSION_TIMEOUT, "Session-Timeout", RADIUS_ATTR_INT32 },
182 	{ RADIUS_ATTR_IDLE_TIMEOUT, "Idle-Timeout", RADIUS_ATTR_INT32 },
183 	{ RADIUS_ATTR_TERMINATION_ACTION, "Termination-Action",
184 	  RADIUS_ATTR_INT32 },
185 	{ RADIUS_ATTR_CALLED_STATION_ID, "Called-Station-Id",
186 	  RADIUS_ATTR_TEXT },
187 	{ RADIUS_ATTR_CALLING_STATION_ID, "Calling-Station-Id",
188 	  RADIUS_ATTR_TEXT },
189 	{ RADIUS_ATTR_NAS_IDENTIFIER, "NAS-Identifier", RADIUS_ATTR_TEXT },
190 	{ RADIUS_ATTR_PROXY_STATE, "Proxy-State", RADIUS_ATTR_UNDIST },
191 	{ RADIUS_ATTR_ACCT_STATUS_TYPE, "Acct-Status-Type",
192 	  RADIUS_ATTR_INT32 },
193 	{ RADIUS_ATTR_ACCT_DELAY_TIME, "Acct-Delay-Time", RADIUS_ATTR_INT32 },
194 	{ RADIUS_ATTR_ACCT_INPUT_OCTETS, "Acct-Input-Octets",
195 	  RADIUS_ATTR_INT32 },
196 	{ RADIUS_ATTR_ACCT_OUTPUT_OCTETS, "Acct-Output-Octets",
197 	  RADIUS_ATTR_INT32 },
198 	{ RADIUS_ATTR_ACCT_SESSION_ID, "Acct-Session-Id", RADIUS_ATTR_TEXT },
199 	{ RADIUS_ATTR_ACCT_AUTHENTIC, "Acct-Authentic", RADIUS_ATTR_INT32 },
200 	{ RADIUS_ATTR_ACCT_SESSION_TIME, "Acct-Session-Time",
201 	  RADIUS_ATTR_INT32 },
202 	{ RADIUS_ATTR_ACCT_INPUT_PACKETS, "Acct-Input-Packets",
203 	  RADIUS_ATTR_INT32 },
204 	{ RADIUS_ATTR_ACCT_OUTPUT_PACKETS, "Acct-Output-Packets",
205 	  RADIUS_ATTR_INT32 },
206 	{ RADIUS_ATTR_ACCT_TERMINATE_CAUSE, "Acct-Terminate-Cause",
207 	  RADIUS_ATTR_INT32 },
208 	{ RADIUS_ATTR_ACCT_MULTI_SESSION_ID, "Acct-Multi-Session-Id",
209 	  RADIUS_ATTR_TEXT },
210 	{ RADIUS_ATTR_ACCT_LINK_COUNT, "Acct-Link-Count", RADIUS_ATTR_INT32 },
211 	{ RADIUS_ATTR_ACCT_INPUT_GIGAWORDS, "Acct-Input-Gigawords",
212 	  RADIUS_ATTR_INT32 },
213 	{ RADIUS_ATTR_ACCT_OUTPUT_GIGAWORDS, "Acct-Output-Gigawords",
214 	  RADIUS_ATTR_INT32 },
215 	{ RADIUS_ATTR_EVENT_TIMESTAMP, "Event-Timestamp",
216 	  RADIUS_ATTR_INT32 },
217 	{ RADIUS_ATTR_NAS_PORT_TYPE, "NAS-Port-Type", RADIUS_ATTR_INT32 },
218 	{ RADIUS_ATTR_TUNNEL_TYPE, "Tunnel-Type", RADIUS_ATTR_HEXDUMP },
219 	{ RADIUS_ATTR_TUNNEL_MEDIUM_TYPE, "Tunnel-Medium-Type",
220 	  RADIUS_ATTR_HEXDUMP },
221 	{ RADIUS_ATTR_TUNNEL_PASSWORD, "Tunnel-Password",
222 	  RADIUS_ATTR_UNDIST },
223 	{ RADIUS_ATTR_CONNECT_INFO, "Connect-Info", RADIUS_ATTR_TEXT },
224 	{ RADIUS_ATTR_EAP_MESSAGE, "EAP-Message", RADIUS_ATTR_UNDIST },
225 	{ RADIUS_ATTR_MESSAGE_AUTHENTICATOR, "Message-Authenticator",
226 	  RADIUS_ATTR_UNDIST },
227 	{ RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID, "Tunnel-Private-Group-Id",
228 	  RADIUS_ATTR_HEXDUMP },
229 	{ RADIUS_ATTR_ACCT_INTERIM_INTERVAL, "Acct-Interim-Interval",
230 	  RADIUS_ATTR_INT32 },
231 	{ RADIUS_ATTR_CHARGEABLE_USER_IDENTITY, "Chargeable-User-Identity",
232 	  RADIUS_ATTR_TEXT },
233 	{ RADIUS_ATTR_NAS_IPV6_ADDRESS, "NAS-IPv6-Address", RADIUS_ATTR_IPV6 },
234 	{ RADIUS_ATTR_ERROR_CAUSE, "Error-Cause", RADIUS_ATTR_INT32 }
235 };
236 #define RADIUS_ATTRS (sizeof(radius_attrs) / sizeof(radius_attrs[0]))
237 
238 
239 static struct radius_attr_type *radius_get_attr_type(u8 type)
240 {
241 	size_t i;
242 
243 	for (i = 0; i < RADIUS_ATTRS; i++) {
244 		if (type == radius_attrs[i].type)
245 			return &radius_attrs[i];
246 	}
247 
248 	return NULL;
249 }
250 
251 
252 static void print_char(char c)
253 {
254 	if (c >= 32 && c < 127)
255 		printf("%c", c);
256 	else
257 		printf("<%02x>", c);
258 }
259 
260 
261 static void radius_msg_dump_attr(struct radius_attr_hdr *hdr)
262 {
263 	struct radius_attr_type *attr;
264 	int i, len;
265 	unsigned char *pos;
266 
267 	attr = radius_get_attr_type(hdr->type);
268 
269 	printf("   Attribute %d (%s) length=%d\n",
270 	       hdr->type, attr ? attr->name : "?Unknown?", hdr->length);
271 
272 	if (attr == NULL || hdr->length < sizeof(struct radius_attr_hdr))
273 		return;
274 
275 	len = hdr->length - sizeof(struct radius_attr_hdr);
276 	pos = (unsigned char *) (hdr + 1);
277 
278 	switch (attr->data_type) {
279 	case RADIUS_ATTR_TEXT:
280 		printf("      Value: '");
281 		for (i = 0; i < len; i++)
282 			print_char(pos[i]);
283 		printf("'\n");
284 		break;
285 
286 	case RADIUS_ATTR_IP:
287 		if (len == 4) {
288 			struct in_addr addr;
289 			os_memcpy(&addr, pos, 4);
290 			printf("      Value: %s\n", inet_ntoa(addr));
291 		} else
292 			printf("      Invalid IP address length %d\n", len);
293 		break;
294 
295 #ifdef CONFIG_IPV6
296 	case RADIUS_ATTR_IPV6:
297 		if (len == 16) {
298 			char buf[128];
299 			const char *atxt;
300 			struct in6_addr *addr = (struct in6_addr *) pos;
301 			atxt = inet_ntop(AF_INET6, addr, buf, sizeof(buf));
302 			printf("      Value: %s\n", atxt ? atxt : "?");
303 		} else
304 			printf("      Invalid IPv6 address length %d\n", len);
305 		break;
306 #endif /* CONFIG_IPV6 */
307 
308 	case RADIUS_ATTR_HEXDUMP:
309 	case RADIUS_ATTR_UNDIST:
310 		printf("      Value:");
311 		for (i = 0; i < len; i++)
312 			printf(" %02x", pos[i]);
313 		printf("\n");
314 		break;
315 
316 	case RADIUS_ATTR_INT32:
317 		if (len == 4)
318 			printf("      Value: %u\n", WPA_GET_BE32(pos));
319 		else
320 			printf("      Invalid INT32 length %d\n", len);
321 		break;
322 
323 	default:
324 		break;
325 	}
326 }
327 
328 
329 void radius_msg_dump(struct radius_msg *msg)
330 {
331 	size_t i;
332 
333 	printf("RADIUS message: code=%d (%s) identifier=%d length=%d\n",
334 	       msg->hdr->code, radius_code_string(msg->hdr->code),
335 	       msg->hdr->identifier, be_to_host16(msg->hdr->length));
336 
337 	for (i = 0; i < msg->attr_used; i++) {
338 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
339 		radius_msg_dump_attr(attr);
340 	}
341 }
342 
343 
344 int radius_msg_finish(struct radius_msg *msg, const u8 *secret,
345 		      size_t secret_len)
346 {
347 	if (secret) {
348 		u8 auth[MD5_MAC_LEN];
349 		struct radius_attr_hdr *attr;
350 
351 		os_memset(auth, 0, MD5_MAC_LEN);
352 		attr = radius_msg_add_attr(msg,
353 					   RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
354 					   auth, MD5_MAC_LEN);
355 		if (attr == NULL) {
356 			wpa_printf(MSG_WARNING, "RADIUS: Could not add "
357 				   "Message-Authenticator");
358 			return -1;
359 		}
360 		msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
361 		hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
362 			 wpabuf_len(msg->buf), (u8 *) (attr + 1));
363 	} else
364 		msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
365 
366 	if (wpabuf_len(msg->buf) > 0xffff) {
367 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
368 			   (unsigned long) wpabuf_len(msg->buf));
369 		return -1;
370 	}
371 	return 0;
372 }
373 
374 
375 int radius_msg_finish_srv(struct radius_msg *msg, const u8 *secret,
376 			  size_t secret_len, const u8 *req_authenticator)
377 {
378 	u8 auth[MD5_MAC_LEN];
379 	struct radius_attr_hdr *attr;
380 	const u8 *addr[4];
381 	size_t len[4];
382 
383 	os_memset(auth, 0, MD5_MAC_LEN);
384 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
385 				   auth, MD5_MAC_LEN);
386 	if (attr == NULL) {
387 		printf("WARNING: Could not add Message-Authenticator\n");
388 		return -1;
389 	}
390 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
391 	os_memcpy(msg->hdr->authenticator, req_authenticator,
392 		  sizeof(msg->hdr->authenticator));
393 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
394 		 wpabuf_len(msg->buf), (u8 *) (attr + 1));
395 
396 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
397 	addr[0] = (u8 *) msg->hdr;
398 	len[0] = 1 + 1 + 2;
399 	addr[1] = req_authenticator;
400 	len[1] = MD5_MAC_LEN;
401 	addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr);
402 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
403 	addr[3] = secret;
404 	len[3] = secret_len;
405 	md5_vector(4, addr, len, msg->hdr->authenticator);
406 
407 	if (wpabuf_len(msg->buf) > 0xffff) {
408 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
409 			   (unsigned long) wpabuf_len(msg->buf));
410 		return -1;
411 	}
412 	return 0;
413 }
414 
415 
416 int radius_msg_finish_das_resp(struct radius_msg *msg, const u8 *secret,
417 			       size_t secret_len,
418 			       const struct radius_hdr *req_hdr)
419 {
420 	const u8 *addr[2];
421 	size_t len[2];
422 	u8 auth[MD5_MAC_LEN];
423 	struct radius_attr_hdr *attr;
424 
425 	os_memset(auth, 0, MD5_MAC_LEN);
426 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
427 				   auth, MD5_MAC_LEN);
428 	if (attr == NULL) {
429 		wpa_printf(MSG_WARNING, "Could not add Message-Authenticator");
430 		return -1;
431 	}
432 
433 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
434 	os_memcpy(msg->hdr->authenticator, req_hdr->authenticator, 16);
435 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
436 		 wpabuf_len(msg->buf), (u8 *) (attr + 1));
437 
438 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
439 	addr[0] = wpabuf_head_u8(msg->buf);
440 	len[0] = wpabuf_len(msg->buf);
441 	addr[1] = secret;
442 	len[1] = secret_len;
443 	if (md5_vector(2, addr, len, msg->hdr->authenticator) < 0)
444 		return -1;
445 
446 	if (wpabuf_len(msg->buf) > 0xffff) {
447 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
448 			   (unsigned long) wpabuf_len(msg->buf));
449 		return -1;
450 	}
451 	return 0;
452 }
453 
454 
455 void radius_msg_finish_acct(struct radius_msg *msg, const u8 *secret,
456 			    size_t secret_len)
457 {
458 	const u8 *addr[2];
459 	size_t len[2];
460 
461 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
462 	os_memset(msg->hdr->authenticator, 0, MD5_MAC_LEN);
463 	addr[0] = wpabuf_head(msg->buf);
464 	len[0] = wpabuf_len(msg->buf);
465 	addr[1] = secret;
466 	len[1] = secret_len;
467 	md5_vector(2, addr, len, msg->hdr->authenticator);
468 
469 	if (wpabuf_len(msg->buf) > 0xffff) {
470 		wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)",
471 			   (unsigned long) wpabuf_len(msg->buf));
472 	}
473 }
474 
475 
476 int radius_msg_verify_acct_req(struct radius_msg *msg, const u8 *secret,
477 			       size_t secret_len)
478 {
479 	const u8 *addr[4];
480 	size_t len[4];
481 	u8 zero[MD5_MAC_LEN];
482 	u8 hash[MD5_MAC_LEN];
483 
484 	os_memset(zero, 0, sizeof(zero));
485 	addr[0] = (u8 *) msg->hdr;
486 	len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN;
487 	addr[1] = zero;
488 	len[1] = MD5_MAC_LEN;
489 	addr[2] = (u8 *) (msg->hdr + 1);
490 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
491 	addr[3] = secret;
492 	len[3] = secret_len;
493 	md5_vector(4, addr, len, hash);
494 	return os_memcmp(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0;
495 }
496 
497 
498 int radius_msg_verify_das_req(struct radius_msg *msg, const u8 *secret,
499 			      size_t secret_len)
500 {
501 	const u8 *addr[4];
502 	size_t len[4];
503 	u8 zero[MD5_MAC_LEN];
504 	u8 hash[MD5_MAC_LEN];
505 	u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
506 	u8 orig_authenticator[16];
507 
508 	struct radius_attr_hdr *attr = NULL, *tmp;
509 	size_t i;
510 
511 	os_memset(zero, 0, sizeof(zero));
512 	addr[0] = (u8 *) msg->hdr;
513 	len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN;
514 	addr[1] = zero;
515 	len[1] = MD5_MAC_LEN;
516 	addr[2] = (u8 *) (msg->hdr + 1);
517 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
518 	addr[3] = secret;
519 	len[3] = secret_len;
520 	md5_vector(4, addr, len, hash);
521 	if (os_memcmp(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0)
522 		return 1;
523 
524 	for (i = 0; i < msg->attr_used; i++) {
525 		tmp = radius_get_attr_hdr(msg, i);
526 		if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
527 			if (attr != NULL) {
528 				wpa_printf(MSG_WARNING, "Multiple "
529 					   "Message-Authenticator attributes "
530 					   "in RADIUS message");
531 				return 1;
532 			}
533 			attr = tmp;
534 		}
535 	}
536 
537 	if (attr == NULL) {
538 		/* Message-Authenticator is MAY; not required */
539 		return 0;
540 	}
541 
542 	os_memcpy(orig, attr + 1, MD5_MAC_LEN);
543 	os_memset(attr + 1, 0, MD5_MAC_LEN);
544 	os_memcpy(orig_authenticator, msg->hdr->authenticator,
545 		  sizeof(orig_authenticator));
546 	os_memset(msg->hdr->authenticator, 0,
547 		  sizeof(msg->hdr->authenticator));
548 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
549 		 wpabuf_len(msg->buf), auth);
550 	os_memcpy(attr + 1, orig, MD5_MAC_LEN);
551 	os_memcpy(msg->hdr->authenticator, orig_authenticator,
552 		  sizeof(orig_authenticator));
553 
554 	return os_memcmp(orig, auth, MD5_MAC_LEN) != 0;
555 }
556 
557 
558 static int radius_msg_add_attr_to_array(struct radius_msg *msg,
559 					struct radius_attr_hdr *attr)
560 {
561 	if (msg->attr_used >= msg->attr_size) {
562 		size_t *nattr_pos;
563 		int nlen = msg->attr_size * 2;
564 
565 		nattr_pos = os_realloc_array(msg->attr_pos, nlen,
566 					     sizeof(*msg->attr_pos));
567 		if (nattr_pos == NULL)
568 			return -1;
569 
570 		msg->attr_pos = nattr_pos;
571 		msg->attr_size = nlen;
572 	}
573 
574 	msg->attr_pos[msg->attr_used++] =
575 		(unsigned char *) attr - wpabuf_head_u8(msg->buf);
576 
577 	return 0;
578 }
579 
580 
581 struct radius_attr_hdr *radius_msg_add_attr(struct radius_msg *msg, u8 type,
582 					    const u8 *data, size_t data_len)
583 {
584 	size_t buf_needed;
585 	struct radius_attr_hdr *attr;
586 
587 	if (data_len > RADIUS_MAX_ATTR_LEN) {
588 		printf("radius_msg_add_attr: too long attribute (%lu bytes)\n",
589 		       (unsigned long) data_len);
590 		return NULL;
591 	}
592 
593 	buf_needed = sizeof(*attr) + data_len;
594 
595 	if (wpabuf_tailroom(msg->buf) < buf_needed) {
596 		/* allocate more space for message buffer */
597 		if (wpabuf_resize(&msg->buf, buf_needed) < 0)
598 			return NULL;
599 		msg->hdr = wpabuf_mhead(msg->buf);
600 	}
601 
602 	attr = wpabuf_put(msg->buf, sizeof(struct radius_attr_hdr));
603 	attr->type = type;
604 	attr->length = sizeof(*attr) + data_len;
605 	wpabuf_put_data(msg->buf, data, data_len);
606 
607 	if (radius_msg_add_attr_to_array(msg, attr))
608 		return NULL;
609 
610 	return attr;
611 }
612 
613 
614 /**
615  * radius_msg_parse - Parse a RADIUS message
616  * @data: RADIUS message to be parsed
617  * @len: Length of data buffer in octets
618  * Returns: Parsed RADIUS message or %NULL on failure
619  *
620  * This parses a RADIUS message and makes a copy of its data. The caller is
621  * responsible for freeing the returned data with radius_msg_free().
622  */
623 struct radius_msg * radius_msg_parse(const u8 *data, size_t len)
624 {
625 	struct radius_msg *msg;
626 	struct radius_hdr *hdr;
627 	struct radius_attr_hdr *attr;
628 	size_t msg_len;
629 	unsigned char *pos, *end;
630 
631 	if (data == NULL || len < sizeof(*hdr))
632 		return NULL;
633 
634 	hdr = (struct radius_hdr *) data;
635 
636 	msg_len = be_to_host16(hdr->length);
637 	if (msg_len < sizeof(*hdr) || msg_len > len) {
638 		wpa_printf(MSG_INFO, "RADIUS: Invalid message length");
639 		return NULL;
640 	}
641 
642 	if (msg_len < len) {
643 		wpa_printf(MSG_DEBUG, "RADIUS: Ignored %lu extra bytes after "
644 			   "RADIUS message", (unsigned long) len - msg_len);
645 	}
646 
647 	msg = os_zalloc(sizeof(*msg));
648 	if (msg == NULL)
649 		return NULL;
650 
651 	msg->buf = wpabuf_alloc_copy(data, msg_len);
652 	if (msg->buf == NULL || radius_msg_initialize(msg)) {
653 		radius_msg_free(msg);
654 		return NULL;
655 	}
656 	msg->hdr = wpabuf_mhead(msg->buf);
657 
658 	/* parse attributes */
659 	pos = wpabuf_mhead_u8(msg->buf) + sizeof(struct radius_hdr);
660 	end = wpabuf_mhead_u8(msg->buf) + wpabuf_len(msg->buf);
661 	while (pos < end) {
662 		if ((size_t) (end - pos) < sizeof(*attr))
663 			goto fail;
664 
665 		attr = (struct radius_attr_hdr *) pos;
666 
667 		if (pos + attr->length > end || attr->length < sizeof(*attr))
668 			goto fail;
669 
670 		/* TODO: check that attr->length is suitable for attr->type */
671 
672 		if (radius_msg_add_attr_to_array(msg, attr))
673 			goto fail;
674 
675 		pos += attr->length;
676 	}
677 
678 	return msg;
679 
680  fail:
681 	radius_msg_free(msg);
682 	return NULL;
683 }
684 
685 
686 int radius_msg_add_eap(struct radius_msg *msg, const u8 *data, size_t data_len)
687 {
688 	const u8 *pos = data;
689 	size_t left = data_len;
690 
691 	while (left > 0) {
692 		int len;
693 		if (left > RADIUS_MAX_ATTR_LEN)
694 			len = RADIUS_MAX_ATTR_LEN;
695 		else
696 			len = left;
697 
698 		if (!radius_msg_add_attr(msg, RADIUS_ATTR_EAP_MESSAGE,
699 					 pos, len))
700 			return 0;
701 
702 		pos += len;
703 		left -= len;
704 	}
705 
706 	return 1;
707 }
708 
709 
710 struct wpabuf * radius_msg_get_eap(struct radius_msg *msg)
711 {
712 	struct wpabuf *eap;
713 	size_t len, i;
714 	struct radius_attr_hdr *attr;
715 
716 	if (msg == NULL)
717 		return NULL;
718 
719 	len = 0;
720 	for (i = 0; i < msg->attr_used; i++) {
721 		attr = radius_get_attr_hdr(msg, i);
722 		if (attr->type == RADIUS_ATTR_EAP_MESSAGE &&
723 		    attr->length > sizeof(struct radius_attr_hdr))
724 			len += attr->length - sizeof(struct radius_attr_hdr);
725 	}
726 
727 	if (len == 0)
728 		return NULL;
729 
730 	eap = wpabuf_alloc(len);
731 	if (eap == NULL)
732 		return NULL;
733 
734 	for (i = 0; i < msg->attr_used; i++) {
735 		attr = radius_get_attr_hdr(msg, i);
736 		if (attr->type == RADIUS_ATTR_EAP_MESSAGE &&
737 		    attr->length > sizeof(struct radius_attr_hdr)) {
738 			int flen = attr->length - sizeof(*attr);
739 			wpabuf_put_data(eap, attr + 1, flen);
740 		}
741 	}
742 
743 	return eap;
744 }
745 
746 
747 int radius_msg_verify_msg_auth(struct radius_msg *msg, const u8 *secret,
748 			       size_t secret_len, const u8 *req_auth)
749 {
750 	u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
751 	u8 orig_authenticator[16];
752 	struct radius_attr_hdr *attr = NULL, *tmp;
753 	size_t i;
754 
755 	for (i = 0; i < msg->attr_used; i++) {
756 		tmp = radius_get_attr_hdr(msg, i);
757 		if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
758 			if (attr != NULL) {
759 				printf("Multiple Message-Authenticator "
760 				       "attributes in RADIUS message\n");
761 				return 1;
762 			}
763 			attr = tmp;
764 		}
765 	}
766 
767 	if (attr == NULL) {
768 		printf("No Message-Authenticator attribute found\n");
769 		return 1;
770 	}
771 
772 	os_memcpy(orig, attr + 1, MD5_MAC_LEN);
773 	os_memset(attr + 1, 0, MD5_MAC_LEN);
774 	if (req_auth) {
775 		os_memcpy(orig_authenticator, msg->hdr->authenticator,
776 			  sizeof(orig_authenticator));
777 		os_memcpy(msg->hdr->authenticator, req_auth,
778 			  sizeof(msg->hdr->authenticator));
779 	}
780 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
781 		 wpabuf_len(msg->buf), auth);
782 	os_memcpy(attr + 1, orig, MD5_MAC_LEN);
783 	if (req_auth) {
784 		os_memcpy(msg->hdr->authenticator, orig_authenticator,
785 			  sizeof(orig_authenticator));
786 	}
787 
788 	if (os_memcmp(orig, auth, MD5_MAC_LEN) != 0) {
789 		printf("Invalid Message-Authenticator!\n");
790 		return 1;
791 	}
792 
793 	return 0;
794 }
795 
796 
797 int radius_msg_verify(struct radius_msg *msg, const u8 *secret,
798 		      size_t secret_len, struct radius_msg *sent_msg, int auth)
799 {
800 	const u8 *addr[4];
801 	size_t len[4];
802 	u8 hash[MD5_MAC_LEN];
803 
804 	if (sent_msg == NULL) {
805 		printf("No matching Access-Request message found\n");
806 		return 1;
807 	}
808 
809 	if (auth &&
810 	    radius_msg_verify_msg_auth(msg, secret, secret_len,
811 				       sent_msg->hdr->authenticator)) {
812 		return 1;
813 	}
814 
815 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
816 	addr[0] = (u8 *) msg->hdr;
817 	len[0] = 1 + 1 + 2;
818 	addr[1] = sent_msg->hdr->authenticator;
819 	len[1] = MD5_MAC_LEN;
820 	addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr);
821 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
822 	addr[3] = secret;
823 	len[3] = secret_len;
824 	md5_vector(4, addr, len, hash);
825 	if (os_memcmp(hash, msg->hdr->authenticator, MD5_MAC_LEN) != 0) {
826 		printf("Response Authenticator invalid!\n");
827 		return 1;
828 	}
829 
830 	return 0;
831 }
832 
833 
834 int radius_msg_copy_attr(struct radius_msg *dst, struct radius_msg *src,
835 			 u8 type)
836 {
837 	struct radius_attr_hdr *attr;
838 	size_t i;
839 	int count = 0;
840 
841 	for (i = 0; i < src->attr_used; i++) {
842 		attr = radius_get_attr_hdr(src, i);
843 		if (attr->type == type && attr->length >= sizeof(*attr)) {
844 			if (!radius_msg_add_attr(dst, type, (u8 *) (attr + 1),
845 						 attr->length - sizeof(*attr)))
846 				return -1;
847 			count++;
848 		}
849 	}
850 
851 	return count;
852 }
853 
854 
855 /* Create Request Authenticator. The value should be unique over the lifetime
856  * of the shared secret between authenticator and authentication server.
857  * Use one-way MD5 hash calculated from current timestamp and some data given
858  * by the caller. */
859 void radius_msg_make_authenticator(struct radius_msg *msg,
860 				   const u8 *data, size_t len)
861 {
862 	struct os_time tv;
863 	long int l;
864 	const u8 *addr[3];
865 	size_t elen[3];
866 
867 	os_get_time(&tv);
868 	l = os_random();
869 	addr[0] = (u8 *) &tv;
870 	elen[0] = sizeof(tv);
871 	addr[1] = data;
872 	elen[1] = len;
873 	addr[2] = (u8 *) &l;
874 	elen[2] = sizeof(l);
875 	md5_vector(3, addr, elen, msg->hdr->authenticator);
876 }
877 
878 
879 /* Get Vendor-specific RADIUS Attribute from a parsed RADIUS message.
880  * Returns the Attribute payload and sets alen to indicate the length of the
881  * payload if a vendor attribute with subtype is found, otherwise returns NULL.
882  * The returned payload is allocated with os_malloc() and caller must free it
883  * by calling os_free().
884  */
885 static u8 *radius_msg_get_vendor_attr(struct radius_msg *msg, u32 vendor,
886 				      u8 subtype, size_t *alen)
887 {
888 	u8 *data, *pos;
889 	size_t i, len;
890 
891 	if (msg == NULL)
892 		return NULL;
893 
894 	for (i = 0; i < msg->attr_used; i++) {
895 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
896 		size_t left;
897 		u32 vendor_id;
898 		struct radius_attr_vendor *vhdr;
899 
900 		if (attr->type != RADIUS_ATTR_VENDOR_SPECIFIC ||
901 		    attr->length < sizeof(*attr))
902 			continue;
903 
904 		left = attr->length - sizeof(*attr);
905 		if (left < 4)
906 			continue;
907 
908 		pos = (u8 *) (attr + 1);
909 
910 		os_memcpy(&vendor_id, pos, 4);
911 		pos += 4;
912 		left -= 4;
913 
914 		if (ntohl(vendor_id) != vendor)
915 			continue;
916 
917 		while (left >= sizeof(*vhdr)) {
918 			vhdr = (struct radius_attr_vendor *) pos;
919 			if (vhdr->vendor_length > left ||
920 			    vhdr->vendor_length < sizeof(*vhdr)) {
921 				left = 0;
922 				break;
923 			}
924 			if (vhdr->vendor_type != subtype) {
925 				pos += vhdr->vendor_length;
926 				left -= vhdr->vendor_length;
927 				continue;
928 			}
929 
930 			len = vhdr->vendor_length - sizeof(*vhdr);
931 			data = os_malloc(len);
932 			if (data == NULL)
933 				return NULL;
934 			os_memcpy(data, pos + sizeof(*vhdr), len);
935 			if (alen)
936 				*alen = len;
937 			return data;
938 		}
939 	}
940 
941 	return NULL;
942 }
943 
944 
945 static u8 * decrypt_ms_key(const u8 *key, size_t len,
946 			   const u8 *req_authenticator,
947 			   const u8 *secret, size_t secret_len, size_t *reslen)
948 {
949 	u8 *plain, *ppos, *res;
950 	const u8 *pos;
951 	size_t left, plen;
952 	u8 hash[MD5_MAC_LEN];
953 	int i, first = 1;
954 	const u8 *addr[3];
955 	size_t elen[3];
956 
957 	/* key: 16-bit salt followed by encrypted key info */
958 
959 	if (len < 2 + 16)
960 		return NULL;
961 
962 	pos = key + 2;
963 	left = len - 2;
964 	if (left % 16) {
965 		printf("Invalid ms key len %lu\n", (unsigned long) left);
966 		return NULL;
967 	}
968 
969 	plen = left;
970 	ppos = plain = os_malloc(plen);
971 	if (plain == NULL)
972 		return NULL;
973 	plain[0] = 0;
974 
975 	while (left > 0) {
976 		/* b(1) = MD5(Secret + Request-Authenticator + Salt)
977 		 * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
978 
979 		addr[0] = secret;
980 		elen[0] = secret_len;
981 		if (first) {
982 			addr[1] = req_authenticator;
983 			elen[1] = MD5_MAC_LEN;
984 			addr[2] = key;
985 			elen[2] = 2; /* Salt */
986 		} else {
987 			addr[1] = pos - MD5_MAC_LEN;
988 			elen[1] = MD5_MAC_LEN;
989 		}
990 		md5_vector(first ? 3 : 2, addr, elen, hash);
991 		first = 0;
992 
993 		for (i = 0; i < MD5_MAC_LEN; i++)
994 			*ppos++ = *pos++ ^ hash[i];
995 		left -= MD5_MAC_LEN;
996 	}
997 
998 	if (plain[0] == 0 || plain[0] > plen - 1) {
999 		printf("Failed to decrypt MPPE key\n");
1000 		os_free(plain);
1001 		return NULL;
1002 	}
1003 
1004 	res = os_malloc(plain[0]);
1005 	if (res == NULL) {
1006 		os_free(plain);
1007 		return NULL;
1008 	}
1009 	os_memcpy(res, plain + 1, plain[0]);
1010 	if (reslen)
1011 		*reslen = plain[0];
1012 	os_free(plain);
1013 	return res;
1014 }
1015 
1016 
1017 static void encrypt_ms_key(const u8 *key, size_t key_len, u16 salt,
1018 			   const u8 *req_authenticator,
1019 			   const u8 *secret, size_t secret_len,
1020 			   u8 *ebuf, size_t *elen)
1021 {
1022 	int i, len, first = 1;
1023 	u8 hash[MD5_MAC_LEN], saltbuf[2], *pos;
1024 	const u8 *addr[3];
1025 	size_t _len[3];
1026 
1027 	WPA_PUT_BE16(saltbuf, salt);
1028 
1029 	len = 1 + key_len;
1030 	if (len & 0x0f) {
1031 		len = (len & 0xf0) + 16;
1032 	}
1033 	os_memset(ebuf, 0, len);
1034 	ebuf[0] = key_len;
1035 	os_memcpy(ebuf + 1, key, key_len);
1036 
1037 	*elen = len;
1038 
1039 	pos = ebuf;
1040 	while (len > 0) {
1041 		/* b(1) = MD5(Secret + Request-Authenticator + Salt)
1042 		 * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
1043 		addr[0] = secret;
1044 		_len[0] = secret_len;
1045 		if (first) {
1046 			addr[1] = req_authenticator;
1047 			_len[1] = MD5_MAC_LEN;
1048 			addr[2] = saltbuf;
1049 			_len[2] = sizeof(saltbuf);
1050 		} else {
1051 			addr[1] = pos - MD5_MAC_LEN;
1052 			_len[1] = MD5_MAC_LEN;
1053 		}
1054 		md5_vector(first ? 3 : 2, addr, _len, hash);
1055 		first = 0;
1056 
1057 		for (i = 0; i < MD5_MAC_LEN; i++)
1058 			*pos++ ^= hash[i];
1059 
1060 		len -= MD5_MAC_LEN;
1061 	}
1062 }
1063 
1064 
1065 struct radius_ms_mppe_keys *
1066 radius_msg_get_ms_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
1067 		       const u8 *secret, size_t secret_len)
1068 {
1069 	u8 *key;
1070 	size_t keylen;
1071 	struct radius_ms_mppe_keys *keys;
1072 
1073 	if (msg == NULL || sent_msg == NULL)
1074 		return NULL;
1075 
1076 	keys = os_zalloc(sizeof(*keys));
1077 	if (keys == NULL)
1078 		return NULL;
1079 
1080 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
1081 					 RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY,
1082 					 &keylen);
1083 	if (key) {
1084 		keys->send = decrypt_ms_key(key, keylen,
1085 					    sent_msg->hdr->authenticator,
1086 					    secret, secret_len,
1087 					    &keys->send_len);
1088 		os_free(key);
1089 	}
1090 
1091 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
1092 					 RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY,
1093 					 &keylen);
1094 	if (key) {
1095 		keys->recv = decrypt_ms_key(key, keylen,
1096 					    sent_msg->hdr->authenticator,
1097 					    secret, secret_len,
1098 					    &keys->recv_len);
1099 		os_free(key);
1100 	}
1101 
1102 	return keys;
1103 }
1104 
1105 
1106 struct radius_ms_mppe_keys *
1107 radius_msg_get_cisco_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
1108 			  const u8 *secret, size_t secret_len)
1109 {
1110 	u8 *key;
1111 	size_t keylen;
1112 	struct radius_ms_mppe_keys *keys;
1113 
1114 	if (msg == NULL || sent_msg == NULL)
1115 		return NULL;
1116 
1117 	keys = os_zalloc(sizeof(*keys));
1118 	if (keys == NULL)
1119 		return NULL;
1120 
1121 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_CISCO,
1122 					 RADIUS_CISCO_AV_PAIR, &keylen);
1123 	if (key && keylen == 51 &&
1124 	    os_memcmp(key, "leap:session-key=", 17) == 0) {
1125 		keys->recv = decrypt_ms_key(key + 17, keylen - 17,
1126 					    sent_msg->hdr->authenticator,
1127 					    secret, secret_len,
1128 					    &keys->recv_len);
1129 	}
1130 	os_free(key);
1131 
1132 	return keys;
1133 }
1134 
1135 
1136 int radius_msg_add_mppe_keys(struct radius_msg *msg,
1137 			     const u8 *req_authenticator,
1138 			     const u8 *secret, size_t secret_len,
1139 			     const u8 *send_key, size_t send_key_len,
1140 			     const u8 *recv_key, size_t recv_key_len)
1141 {
1142 	struct radius_attr_hdr *attr;
1143 	u32 vendor_id = htonl(RADIUS_VENDOR_ID_MICROSOFT);
1144 	u8 *buf;
1145 	struct radius_attr_vendor *vhdr;
1146 	u8 *pos;
1147 	size_t elen;
1148 	int hlen;
1149 	u16 salt;
1150 
1151 	hlen = sizeof(vendor_id) + sizeof(*vhdr) + 2;
1152 
1153 	/* MS-MPPE-Send-Key */
1154 	buf = os_malloc(hlen + send_key_len + 16);
1155 	if (buf == NULL) {
1156 		return 0;
1157 	}
1158 	pos = buf;
1159 	os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1160 	pos += sizeof(vendor_id);
1161 	vhdr = (struct radius_attr_vendor *) pos;
1162 	vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY;
1163 	pos = (u8 *) (vhdr + 1);
1164 	salt = os_random() | 0x8000;
1165 	WPA_PUT_BE16(pos, salt);
1166 	pos += 2;
1167 	encrypt_ms_key(send_key, send_key_len, salt, req_authenticator, secret,
1168 		       secret_len, pos, &elen);
1169 	vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1170 
1171 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1172 				   buf, hlen + elen);
1173 	os_free(buf);
1174 	if (attr == NULL) {
1175 		return 0;
1176 	}
1177 
1178 	/* MS-MPPE-Recv-Key */
1179 	buf = os_malloc(hlen + send_key_len + 16);
1180 	if (buf == NULL) {
1181 		return 0;
1182 	}
1183 	pos = buf;
1184 	os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1185 	pos += sizeof(vendor_id);
1186 	vhdr = (struct radius_attr_vendor *) pos;
1187 	vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY;
1188 	pos = (u8 *) (vhdr + 1);
1189 	salt ^= 1;
1190 	WPA_PUT_BE16(pos, salt);
1191 	pos += 2;
1192 	encrypt_ms_key(recv_key, recv_key_len, salt, req_authenticator, secret,
1193 		       secret_len, pos, &elen);
1194 	vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1195 
1196 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1197 				   buf, hlen + elen);
1198 	os_free(buf);
1199 	if (attr == NULL) {
1200 		return 0;
1201 	}
1202 
1203 	return 1;
1204 }
1205 
1206 
1207 /* Add User-Password attribute to a RADIUS message and encrypt it as specified
1208  * in RFC 2865, Chap. 5.2 */
1209 struct radius_attr_hdr *
1210 radius_msg_add_attr_user_password(struct radius_msg *msg,
1211 				  const u8 *data, size_t data_len,
1212 				  const u8 *secret, size_t secret_len)
1213 {
1214 	u8 buf[128];
1215 	size_t padlen, i, buf_len, pos;
1216 	const u8 *addr[2];
1217 	size_t len[2];
1218 	u8 hash[16];
1219 
1220 	if (data_len > 128)
1221 		return NULL;
1222 
1223 	os_memcpy(buf, data, data_len);
1224 	buf_len = data_len;
1225 
1226 	padlen = data_len % 16;
1227 	if (padlen && data_len < sizeof(buf)) {
1228 		padlen = 16 - padlen;
1229 		os_memset(buf + data_len, 0, padlen);
1230 		buf_len += padlen;
1231 	}
1232 
1233 	addr[0] = secret;
1234 	len[0] = secret_len;
1235 	addr[1] = msg->hdr->authenticator;
1236 	len[1] = 16;
1237 	md5_vector(2, addr, len, hash);
1238 
1239 	for (i = 0; i < 16; i++)
1240 		buf[i] ^= hash[i];
1241 	pos = 16;
1242 
1243 	while (pos < buf_len) {
1244 		addr[0] = secret;
1245 		len[0] = secret_len;
1246 		addr[1] = &buf[pos - 16];
1247 		len[1] = 16;
1248 		md5_vector(2, addr, len, hash);
1249 
1250 		for (i = 0; i < 16; i++)
1251 			buf[pos + i] ^= hash[i];
1252 
1253 		pos += 16;
1254 	}
1255 
1256 	return radius_msg_add_attr(msg, RADIUS_ATTR_USER_PASSWORD,
1257 				   buf, buf_len);
1258 }
1259 
1260 
1261 int radius_msg_get_attr(struct radius_msg *msg, u8 type, u8 *buf, size_t len)
1262 {
1263 	struct radius_attr_hdr *attr = NULL, *tmp;
1264 	size_t i, dlen;
1265 
1266 	for (i = 0; i < msg->attr_used; i++) {
1267 		tmp = radius_get_attr_hdr(msg, i);
1268 		if (tmp->type == type) {
1269 			attr = tmp;
1270 			break;
1271 		}
1272 	}
1273 
1274 	if (!attr || attr->length < sizeof(*attr))
1275 		return -1;
1276 
1277 	dlen = attr->length - sizeof(*attr);
1278 	if (buf)
1279 		os_memcpy(buf, (attr + 1), dlen > len ? len : dlen);
1280 	return dlen;
1281 }
1282 
1283 
1284 int radius_msg_get_attr_ptr(struct radius_msg *msg, u8 type, u8 **buf,
1285 			    size_t *len, const u8 *start)
1286 {
1287 	size_t i;
1288 	struct radius_attr_hdr *attr = NULL, *tmp;
1289 
1290 	for (i = 0; i < msg->attr_used; i++) {
1291 		tmp = radius_get_attr_hdr(msg, i);
1292 		if (tmp->type == type &&
1293 		    (start == NULL || (u8 *) tmp > start)) {
1294 			attr = tmp;
1295 			break;
1296 		}
1297 	}
1298 
1299 	if (!attr || attr->length < sizeof(*attr))
1300 		return -1;
1301 
1302 	*buf = (u8 *) (attr + 1);
1303 	*len = attr->length - sizeof(*attr);
1304 	return 0;
1305 }
1306 
1307 
1308 int radius_msg_count_attr(struct radius_msg *msg, u8 type, int min_len)
1309 {
1310 	size_t i;
1311 	int count;
1312 
1313 	for (count = 0, i = 0; i < msg->attr_used; i++) {
1314 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
1315 		if (attr->type == type &&
1316 		    attr->length >= sizeof(struct radius_attr_hdr) + min_len)
1317 			count++;
1318 	}
1319 
1320 	return count;
1321 }
1322 
1323 
1324 struct radius_tunnel_attrs {
1325 	int tag_used;
1326 	int type; /* Tunnel-Type */
1327 	int medium_type; /* Tunnel-Medium-Type */
1328 	int vlanid;
1329 };
1330 
1331 
1332 /**
1333  * radius_msg_get_vlanid - Parse RADIUS attributes for VLAN tunnel information
1334  * @msg: RADIUS message
1335  * Returns: VLAN ID for the first tunnel configuration of -1 if none is found
1336  */
1337 int radius_msg_get_vlanid(struct radius_msg *msg)
1338 {
1339 	struct radius_tunnel_attrs tunnel[RADIUS_TUNNEL_TAGS], *tun;
1340 	size_t i;
1341 	struct radius_attr_hdr *attr = NULL;
1342 	const u8 *data;
1343 	char buf[10];
1344 	size_t dlen;
1345 
1346 	os_memset(&tunnel, 0, sizeof(tunnel));
1347 
1348 	for (i = 0; i < msg->attr_used; i++) {
1349 		attr = radius_get_attr_hdr(msg, i);
1350 		if (attr->length < sizeof(*attr))
1351 			return -1;
1352 		data = (const u8 *) (attr + 1);
1353 		dlen = attr->length - sizeof(*attr);
1354 		if (attr->length < 3)
1355 			continue;
1356 		if (data[0] >= RADIUS_TUNNEL_TAGS)
1357 			tun = &tunnel[0];
1358 		else
1359 			tun = &tunnel[data[0]];
1360 
1361 		switch (attr->type) {
1362 		case RADIUS_ATTR_TUNNEL_TYPE:
1363 			if (attr->length != 6)
1364 				break;
1365 			tun->tag_used++;
1366 			tun->type = WPA_GET_BE24(data + 1);
1367 			break;
1368 		case RADIUS_ATTR_TUNNEL_MEDIUM_TYPE:
1369 			if (attr->length != 6)
1370 				break;
1371 			tun->tag_used++;
1372 			tun->medium_type = WPA_GET_BE24(data + 1);
1373 			break;
1374 		case RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID:
1375 			if (data[0] < RADIUS_TUNNEL_TAGS) {
1376 				data++;
1377 				dlen--;
1378 			}
1379 			if (dlen >= sizeof(buf))
1380 				break;
1381 			os_memcpy(buf, data, dlen);
1382 			buf[dlen] = '\0';
1383 			tun->tag_used++;
1384 			tun->vlanid = atoi(buf);
1385 			break;
1386 		}
1387 	}
1388 
1389 	for (i = 0; i < RADIUS_TUNNEL_TAGS; i++) {
1390 		tun = &tunnel[i];
1391 		if (tun->tag_used &&
1392 		    tun->type == RADIUS_TUNNEL_TYPE_VLAN &&
1393 		    tun->medium_type == RADIUS_TUNNEL_MEDIUM_TYPE_802 &&
1394 		    tun->vlanid > 0)
1395 			return tun->vlanid;
1396 	}
1397 
1398 	return -1;
1399 }
1400 
1401 
1402 /**
1403  * radius_msg_get_tunnel_password - Parse RADIUS attribute Tunnel-Password
1404  * @msg: Received RADIUS message
1405  * @keylen: Length of returned password
1406  * @secret: RADIUS shared secret
1407  * @secret_len: Length of secret
1408  * @sent_msg: Sent RADIUS message
1409  * @n: Number of password attribute to return (starting with 0)
1410  * Returns: Pointer to n-th password (free with os_free) or %NULL
1411  */
1412 char * radius_msg_get_tunnel_password(struct radius_msg *msg, int *keylen,
1413 				      const u8 *secret, size_t secret_len,
1414 				      struct radius_msg *sent_msg, size_t n)
1415 {
1416 	u8 *buf = NULL;
1417 	size_t buflen;
1418 	const u8 *salt;
1419 	u8 *str;
1420 	const u8 *addr[3];
1421 	size_t len[3];
1422 	u8 hash[16];
1423 	u8 *pos;
1424 	size_t i, j = 0;
1425 	struct radius_attr_hdr *attr;
1426 	const u8 *data;
1427 	size_t dlen;
1428 	const u8 *fdata = NULL; /* points to found item */
1429 	size_t fdlen = -1;
1430 	char *ret = NULL;
1431 
1432 	/* find n-th valid Tunnel-Password attribute */
1433 	for (i = 0; i < msg->attr_used; i++) {
1434 		attr = radius_get_attr_hdr(msg, i);
1435 		if (attr == NULL ||
1436 		    attr->type != RADIUS_ATTR_TUNNEL_PASSWORD) {
1437 			continue;
1438 		}
1439 		if (attr->length <= 5)
1440 			continue;
1441 		data = (const u8 *) (attr + 1);
1442 		dlen = attr->length - sizeof(*attr);
1443 		if (dlen <= 3 || dlen % 16 != 3)
1444 			continue;
1445 		j++;
1446 		if (j <= n)
1447 			continue;
1448 
1449 		fdata = data;
1450 		fdlen = dlen;
1451 		break;
1452 	}
1453 	if (fdata == NULL)
1454 		goto out;
1455 
1456 	/* alloc writable memory for decryption */
1457 	buf = os_malloc(fdlen);
1458 	if (buf == NULL)
1459 		goto out;
1460 	os_memcpy(buf, fdata, fdlen);
1461 	buflen = fdlen;
1462 
1463 	/* init pointers */
1464 	salt = buf + 1;
1465 	str = buf + 3;
1466 
1467 	/* decrypt blocks */
1468 	pos = buf + buflen - 16; /* last block */
1469 	while (pos >= str + 16) { /* all but the first block */
1470 		addr[0] = secret;
1471 		len[0] = secret_len;
1472 		addr[1] = pos - 16;
1473 		len[1] = 16;
1474 		md5_vector(2, addr, len, hash);
1475 
1476 		for (i = 0; i < 16; i++)
1477 			pos[i] ^= hash[i];
1478 
1479 		pos -= 16;
1480 	}
1481 
1482 	/* decrypt first block */
1483 	if (str != pos)
1484 		goto out;
1485 	addr[0] = secret;
1486 	len[0] = secret_len;
1487 	addr[1] = sent_msg->hdr->authenticator;
1488 	len[1] = 16;
1489 	addr[2] = salt;
1490 	len[2] = 2;
1491 	md5_vector(3, addr, len, hash);
1492 
1493 	for (i = 0; i < 16; i++)
1494 		pos[i] ^= hash[i];
1495 
1496 	/* derive plaintext length from first subfield */
1497 	*keylen = (unsigned char) str[0];
1498 	if ((u8 *) (str + *keylen) >= (u8 *) (buf + buflen)) {
1499 		/* decryption error - invalid key length */
1500 		goto out;
1501 	}
1502 	if (*keylen == 0) {
1503 		/* empty password */
1504 		goto out;
1505 	}
1506 
1507 	/* copy passphrase into new buffer */
1508 	ret = os_malloc(*keylen);
1509 	if (ret)
1510 		os_memcpy(ret, str + 1, *keylen);
1511 
1512 out:
1513 	/* return new buffer */
1514 	os_free(buf);
1515 	return ret;
1516 }
1517 
1518 
1519 void radius_free_class(struct radius_class_data *c)
1520 {
1521 	size_t i;
1522 	if (c == NULL)
1523 		return;
1524 	for (i = 0; i < c->count; i++)
1525 		os_free(c->attr[i].data);
1526 	os_free(c->attr);
1527 	c->attr = NULL;
1528 	c->count = 0;
1529 }
1530 
1531 
1532 int radius_copy_class(struct radius_class_data *dst,
1533 		      const struct radius_class_data *src)
1534 {
1535 	size_t i;
1536 
1537 	if (src->attr == NULL)
1538 		return 0;
1539 
1540 	dst->attr = os_calloc(src->count, sizeof(struct radius_attr_data));
1541 	if (dst->attr == NULL)
1542 		return -1;
1543 
1544 	dst->count = 0;
1545 
1546 	for (i = 0; i < src->count; i++) {
1547 		dst->attr[i].data = os_malloc(src->attr[i].len);
1548 		if (dst->attr[i].data == NULL)
1549 			break;
1550 		dst->count++;
1551 		os_memcpy(dst->attr[i].data, src->attr[i].data,
1552 			  src->attr[i].len);
1553 		dst->attr[i].len = src->attr[i].len;
1554 	}
1555 
1556 	return 0;
1557 }
1558 
1559 
1560 u8 radius_msg_find_unlisted_attr(struct radius_msg *msg, u8 *attrs)
1561 {
1562 	size_t i, j;
1563 	struct radius_attr_hdr *attr;
1564 
1565 	for (i = 0; i < msg->attr_used; i++) {
1566 		attr = radius_get_attr_hdr(msg, i);
1567 
1568 		for (j = 0; attrs[j]; j++) {
1569 			if (attr->type == attrs[j])
1570 				break;
1571 		}
1572 
1573 		if (attrs[j] == 0)
1574 			return attr->type; /* unlisted attr */
1575 	}
1576 
1577 	return 0;
1578 }
1579