radius.c revision d5e4923d04122f81300fa68fb07d64ede28fd44d
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 */
21struct 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
52struct radius_hdr * radius_msg_get_hdr(struct radius_msg *msg)
53{
54	return msg->hdr;
55}
56
57
58struct wpabuf * radius_msg_get_buf(struct radius_msg *msg)
59{
60	return msg->buf;
61}
62
63
64static struct radius_attr_hdr *
65radius_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
72static 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
79static 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 */
102struct 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 */
127void 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
138static 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
161struct 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
170static 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
239static 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
252static 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
261static 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
329void 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
344int 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
375int 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
416int 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
455void 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
476int 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
498int 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
558static 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
581struct 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 */
623struct 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
686int 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
710struct 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
747int 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
797int 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
834int 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. */
859void 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 */
885static 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
945static 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
1017static 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
1065struct radius_ms_mppe_keys *
1066radius_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
1106struct radius_ms_mppe_keys *
1107radius_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
1136int 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 */
1209struct radius_attr_hdr *
1210radius_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
1261int 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
1284int 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
1308int 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
1324struct 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 */
1337int 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 */
1412char * 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
1512out:
1513	/* return new buffer */
1514	os_free(buf);
1515	return ret;
1516}
1517
1518
1519void 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
1532int 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
1560u8 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