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1 /*
2  * RADIUS message processing
3  * Copyright (c) 2002-2009, 2011-2014, 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 
radius_msg_get_hdr(struct radius_msg * msg)52 struct radius_hdr * radius_msg_get_hdr(struct radius_msg *msg)
53 {
54 	return msg->hdr;
55 }
56 
57 
radius_msg_get_buf(struct radius_msg * msg)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 *
radius_get_attr_hdr(struct radius_msg * msg,int idx)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 
radius_msg_set_hdr(struct radius_msg * msg,u8 code,u8 identifier)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 
radius_msg_initialize(struct radius_msg * msg)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  */
radius_msg_new(u8 code,u8 identifier)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  */
radius_msg_free(struct radius_msg * msg)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 
radius_code_string(u8 code)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 	{ RADIUS_ATTR_EAP_KEY_NAME, "EAP-Key-Name", RADIUS_ATTR_HEXDUMP },
236 	{ RADIUS_ATTR_MOBILITY_DOMAIN_ID, "Mobility-Domain-Id",
237 	  RADIUS_ATTR_INT32 },
238 	{ RADIUS_ATTR_WLAN_HESSID, "WLAN-HESSID", RADIUS_ATTR_TEXT },
239 	{ RADIUS_ATTR_WLAN_PAIRWISE_CIPHER, "WLAN-Pairwise-Cipher",
240 	  RADIUS_ATTR_HEXDUMP },
241 	{ RADIUS_ATTR_WLAN_GROUP_CIPHER, "WLAN-Group-Cipher",
242 	  RADIUS_ATTR_HEXDUMP },
243 	{ RADIUS_ATTR_WLAN_AKM_SUITE, "WLAN-AKM-Suite",
244 	  RADIUS_ATTR_HEXDUMP },
245 	{ RADIUS_ATTR_WLAN_GROUP_MGMT_CIPHER, "WLAN-Group-Mgmt-Pairwise-Cipher",
246 	  RADIUS_ATTR_HEXDUMP },
247 };
248 #define RADIUS_ATTRS ARRAY_SIZE(radius_attrs)
249 
250 
radius_get_attr_type(u8 type)251 static struct radius_attr_type *radius_get_attr_type(u8 type)
252 {
253 	size_t i;
254 
255 	for (i = 0; i < RADIUS_ATTRS; i++) {
256 		if (type == radius_attrs[i].type)
257 			return &radius_attrs[i];
258 	}
259 
260 	return NULL;
261 }
262 
263 
radius_msg_dump_attr(struct radius_attr_hdr * hdr)264 static void radius_msg_dump_attr(struct radius_attr_hdr *hdr)
265 {
266 	struct radius_attr_type *attr;
267 	int len;
268 	unsigned char *pos;
269 	char buf[1000];
270 
271 	attr = radius_get_attr_type(hdr->type);
272 
273 	wpa_printf(MSG_INFO, "   Attribute %d (%s) length=%d",
274 		   hdr->type, attr ? attr->name : "?Unknown?", hdr->length);
275 
276 	if (attr == NULL || hdr->length < sizeof(struct radius_attr_hdr))
277 		return;
278 
279 	len = hdr->length - sizeof(struct radius_attr_hdr);
280 	pos = (unsigned char *) (hdr + 1);
281 
282 	switch (attr->data_type) {
283 	case RADIUS_ATTR_TEXT:
284 		printf_encode(buf, sizeof(buf), pos, len);
285 		wpa_printf(MSG_INFO, "      Value: '%s'", buf);
286 		break;
287 
288 	case RADIUS_ATTR_IP:
289 		if (len == 4) {
290 			struct in_addr addr;
291 			os_memcpy(&addr, pos, 4);
292 			wpa_printf(MSG_INFO, "      Value: %s",
293 				   inet_ntoa(addr));
294 		} else {
295 			wpa_printf(MSG_INFO, "      Invalid IP address length %d",
296 				   len);
297 		}
298 		break;
299 
300 #ifdef CONFIG_IPV6
301 	case RADIUS_ATTR_IPV6:
302 		if (len == 16) {
303 			const char *atxt;
304 			struct in6_addr *addr = (struct in6_addr *) pos;
305 			atxt = inet_ntop(AF_INET6, addr, buf, sizeof(buf));
306 			wpa_printf(MSG_INFO, "      Value: %s",
307 				   atxt ? atxt : "?");
308 		} else {
309 			wpa_printf(MSG_INFO, "      Invalid IPv6 address length %d",
310 				   len);
311 		}
312 		break;
313 #endif /* CONFIG_IPV6 */
314 
315 	case RADIUS_ATTR_HEXDUMP:
316 	case RADIUS_ATTR_UNDIST:
317 		wpa_snprintf_hex(buf, sizeof(buf), pos, len);
318 		wpa_printf(MSG_INFO, "      Value: %s", buf);
319 		break;
320 
321 	case RADIUS_ATTR_INT32:
322 		if (len == 4)
323 			wpa_printf(MSG_INFO, "      Value: %u",
324 				   WPA_GET_BE32(pos));
325 		else
326 			wpa_printf(MSG_INFO, "      Invalid INT32 length %d",
327 				   len);
328 		break;
329 
330 	default:
331 		break;
332 	}
333 }
334 
335 
radius_msg_dump(struct radius_msg * msg)336 void radius_msg_dump(struct radius_msg *msg)
337 {
338 	size_t i;
339 
340 	wpa_printf(MSG_INFO, "RADIUS message: code=%d (%s) identifier=%d length=%d",
341 		   msg->hdr->code, radius_code_string(msg->hdr->code),
342 		   msg->hdr->identifier, be_to_host16(msg->hdr->length));
343 
344 	for (i = 0; i < msg->attr_used; i++) {
345 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
346 		radius_msg_dump_attr(attr);
347 	}
348 }
349 
350 
radius_msg_finish(struct radius_msg * msg,const u8 * secret,size_t secret_len)351 int radius_msg_finish(struct radius_msg *msg, const u8 *secret,
352 		      size_t secret_len)
353 {
354 	if (secret) {
355 		u8 auth[MD5_MAC_LEN];
356 		struct radius_attr_hdr *attr;
357 
358 		os_memset(auth, 0, MD5_MAC_LEN);
359 		attr = radius_msg_add_attr(msg,
360 					   RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
361 					   auth, MD5_MAC_LEN);
362 		if (attr == NULL) {
363 			wpa_printf(MSG_WARNING, "RADIUS: Could not add "
364 				   "Message-Authenticator");
365 			return -1;
366 		}
367 		msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
368 		hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
369 			 wpabuf_len(msg->buf), (u8 *) (attr + 1));
370 	} else
371 		msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
372 
373 	if (wpabuf_len(msg->buf) > 0xffff) {
374 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
375 			   (unsigned long) wpabuf_len(msg->buf));
376 		return -1;
377 	}
378 	return 0;
379 }
380 
381 
radius_msg_finish_srv(struct radius_msg * msg,const u8 * secret,size_t secret_len,const u8 * req_authenticator)382 int radius_msg_finish_srv(struct radius_msg *msg, const u8 *secret,
383 			  size_t secret_len, const u8 *req_authenticator)
384 {
385 	u8 auth[MD5_MAC_LEN];
386 	struct radius_attr_hdr *attr;
387 	const u8 *addr[4];
388 	size_t len[4];
389 
390 	os_memset(auth, 0, MD5_MAC_LEN);
391 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
392 				   auth, MD5_MAC_LEN);
393 	if (attr == NULL) {
394 		wpa_printf(MSG_ERROR, "WARNING: Could not add Message-Authenticator");
395 		return -1;
396 	}
397 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
398 	os_memcpy(msg->hdr->authenticator, req_authenticator,
399 		  sizeof(msg->hdr->authenticator));
400 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
401 		 wpabuf_len(msg->buf), (u8 *) (attr + 1));
402 
403 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
404 	addr[0] = (u8 *) msg->hdr;
405 	len[0] = 1 + 1 + 2;
406 	addr[1] = req_authenticator;
407 	len[1] = MD5_MAC_LEN;
408 	addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr);
409 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
410 	addr[3] = secret;
411 	len[3] = secret_len;
412 	md5_vector(4, addr, len, msg->hdr->authenticator);
413 
414 	if (wpabuf_len(msg->buf) > 0xffff) {
415 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
416 			   (unsigned long) wpabuf_len(msg->buf));
417 		return -1;
418 	}
419 	return 0;
420 }
421 
422 
radius_msg_finish_das_resp(struct radius_msg * msg,const u8 * secret,size_t secret_len,const struct radius_hdr * req_hdr)423 int radius_msg_finish_das_resp(struct radius_msg *msg, const u8 *secret,
424 			       size_t secret_len,
425 			       const struct radius_hdr *req_hdr)
426 {
427 	const u8 *addr[2];
428 	size_t len[2];
429 	u8 auth[MD5_MAC_LEN];
430 	struct radius_attr_hdr *attr;
431 
432 	os_memset(auth, 0, MD5_MAC_LEN);
433 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
434 				   auth, MD5_MAC_LEN);
435 	if (attr == NULL) {
436 		wpa_printf(MSG_WARNING, "Could not add Message-Authenticator");
437 		return -1;
438 	}
439 
440 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
441 	os_memcpy(msg->hdr->authenticator, req_hdr->authenticator, 16);
442 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
443 		 wpabuf_len(msg->buf), (u8 *) (attr + 1));
444 
445 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
446 	addr[0] = wpabuf_head_u8(msg->buf);
447 	len[0] = wpabuf_len(msg->buf);
448 	addr[1] = secret;
449 	len[1] = secret_len;
450 	if (md5_vector(2, addr, len, msg->hdr->authenticator) < 0)
451 		return -1;
452 
453 	if (wpabuf_len(msg->buf) > 0xffff) {
454 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
455 			   (unsigned long) wpabuf_len(msg->buf));
456 		return -1;
457 	}
458 	return 0;
459 }
460 
461 
radius_msg_finish_acct(struct radius_msg * msg,const u8 * secret,size_t secret_len)462 void radius_msg_finish_acct(struct radius_msg *msg, const u8 *secret,
463 			    size_t secret_len)
464 {
465 	const u8 *addr[2];
466 	size_t len[2];
467 
468 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
469 	os_memset(msg->hdr->authenticator, 0, MD5_MAC_LEN);
470 	addr[0] = wpabuf_head(msg->buf);
471 	len[0] = wpabuf_len(msg->buf);
472 	addr[1] = secret;
473 	len[1] = secret_len;
474 	md5_vector(2, addr, len, msg->hdr->authenticator);
475 
476 	if (wpabuf_len(msg->buf) > 0xffff) {
477 		wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)",
478 			   (unsigned long) wpabuf_len(msg->buf));
479 	}
480 }
481 
482 
radius_msg_finish_acct_resp(struct radius_msg * msg,const u8 * secret,size_t secret_len,const u8 * req_authenticator)483 void radius_msg_finish_acct_resp(struct radius_msg *msg, const u8 *secret,
484 				 size_t secret_len, const u8 *req_authenticator)
485 {
486 	const u8 *addr[2];
487 	size_t len[2];
488 
489 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
490 	os_memcpy(msg->hdr->authenticator, req_authenticator, MD5_MAC_LEN);
491 	addr[0] = wpabuf_head(msg->buf);
492 	len[0] = wpabuf_len(msg->buf);
493 	addr[1] = secret;
494 	len[1] = secret_len;
495 	md5_vector(2, addr, len, msg->hdr->authenticator);
496 
497 	if (wpabuf_len(msg->buf) > 0xffff) {
498 		wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)",
499 			   (unsigned long) wpabuf_len(msg->buf));
500 	}
501 }
502 
503 
radius_msg_verify_acct_req(struct radius_msg * msg,const u8 * secret,size_t secret_len)504 int radius_msg_verify_acct_req(struct radius_msg *msg, const u8 *secret,
505 			       size_t secret_len)
506 {
507 	const u8 *addr[4];
508 	size_t len[4];
509 	u8 zero[MD5_MAC_LEN];
510 	u8 hash[MD5_MAC_LEN];
511 
512 	os_memset(zero, 0, sizeof(zero));
513 	addr[0] = (u8 *) msg->hdr;
514 	len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN;
515 	addr[1] = zero;
516 	len[1] = MD5_MAC_LEN;
517 	addr[2] = (u8 *) (msg->hdr + 1);
518 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
519 	addr[3] = secret;
520 	len[3] = secret_len;
521 	md5_vector(4, addr, len, hash);
522 	return os_memcmp_const(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0;
523 }
524 
525 
radius_msg_verify_das_req(struct radius_msg * msg,const u8 * secret,size_t secret_len)526 int radius_msg_verify_das_req(struct radius_msg *msg, const u8 *secret,
527 			      size_t secret_len)
528 {
529 	const u8 *addr[4];
530 	size_t len[4];
531 	u8 zero[MD5_MAC_LEN];
532 	u8 hash[MD5_MAC_LEN];
533 	u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
534 	u8 orig_authenticator[16];
535 
536 	struct radius_attr_hdr *attr = NULL, *tmp;
537 	size_t i;
538 
539 	os_memset(zero, 0, sizeof(zero));
540 	addr[0] = (u8 *) msg->hdr;
541 	len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN;
542 	addr[1] = zero;
543 	len[1] = MD5_MAC_LEN;
544 	addr[2] = (u8 *) (msg->hdr + 1);
545 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
546 	addr[3] = secret;
547 	len[3] = secret_len;
548 	md5_vector(4, addr, len, hash);
549 	if (os_memcmp_const(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0)
550 		return 1;
551 
552 	for (i = 0; i < msg->attr_used; i++) {
553 		tmp = radius_get_attr_hdr(msg, i);
554 		if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
555 			if (attr != NULL) {
556 				wpa_printf(MSG_WARNING, "Multiple "
557 					   "Message-Authenticator attributes "
558 					   "in RADIUS message");
559 				return 1;
560 			}
561 			attr = tmp;
562 		}
563 	}
564 
565 	if (attr == NULL) {
566 		/* Message-Authenticator is MAY; not required */
567 		return 0;
568 	}
569 
570 	os_memcpy(orig, attr + 1, MD5_MAC_LEN);
571 	os_memset(attr + 1, 0, MD5_MAC_LEN);
572 	os_memcpy(orig_authenticator, msg->hdr->authenticator,
573 		  sizeof(orig_authenticator));
574 	os_memset(msg->hdr->authenticator, 0,
575 		  sizeof(msg->hdr->authenticator));
576 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
577 		 wpabuf_len(msg->buf), auth);
578 	os_memcpy(attr + 1, orig, MD5_MAC_LEN);
579 	os_memcpy(msg->hdr->authenticator, orig_authenticator,
580 		  sizeof(orig_authenticator));
581 
582 	return os_memcmp_const(orig, auth, MD5_MAC_LEN) != 0;
583 }
584 
585 
radius_msg_add_attr_to_array(struct radius_msg * msg,struct radius_attr_hdr * attr)586 static int radius_msg_add_attr_to_array(struct radius_msg *msg,
587 					struct radius_attr_hdr *attr)
588 {
589 	if (msg->attr_used >= msg->attr_size) {
590 		size_t *nattr_pos;
591 		int nlen = msg->attr_size * 2;
592 
593 		nattr_pos = os_realloc_array(msg->attr_pos, nlen,
594 					     sizeof(*msg->attr_pos));
595 		if (nattr_pos == NULL)
596 			return -1;
597 
598 		msg->attr_pos = nattr_pos;
599 		msg->attr_size = nlen;
600 	}
601 
602 	msg->attr_pos[msg->attr_used++] =
603 		(unsigned char *) attr - wpabuf_head_u8(msg->buf);
604 
605 	return 0;
606 }
607 
608 
radius_msg_add_attr(struct radius_msg * msg,u8 type,const u8 * data,size_t data_len)609 struct radius_attr_hdr *radius_msg_add_attr(struct radius_msg *msg, u8 type,
610 					    const u8 *data, size_t data_len)
611 {
612 	size_t buf_needed;
613 	struct radius_attr_hdr *attr;
614 
615 	if (data_len > RADIUS_MAX_ATTR_LEN) {
616 		wpa_printf(MSG_ERROR, "radius_msg_add_attr: too long attribute (%lu bytes)",
617 		       (unsigned long) data_len);
618 		return NULL;
619 	}
620 
621 	buf_needed = sizeof(*attr) + data_len;
622 
623 	if (wpabuf_tailroom(msg->buf) < buf_needed) {
624 		/* allocate more space for message buffer */
625 		if (wpabuf_resize(&msg->buf, buf_needed) < 0)
626 			return NULL;
627 		msg->hdr = wpabuf_mhead(msg->buf);
628 	}
629 
630 	attr = wpabuf_put(msg->buf, sizeof(struct radius_attr_hdr));
631 	attr->type = type;
632 	attr->length = sizeof(*attr) + data_len;
633 	wpabuf_put_data(msg->buf, data, data_len);
634 
635 	if (radius_msg_add_attr_to_array(msg, attr))
636 		return NULL;
637 
638 	return attr;
639 }
640 
641 
642 /**
643  * radius_msg_parse - Parse a RADIUS message
644  * @data: RADIUS message to be parsed
645  * @len: Length of data buffer in octets
646  * Returns: Parsed RADIUS message or %NULL on failure
647  *
648  * This parses a RADIUS message and makes a copy of its data. The caller is
649  * responsible for freeing the returned data with radius_msg_free().
650  */
radius_msg_parse(const u8 * data,size_t len)651 struct radius_msg * radius_msg_parse(const u8 *data, size_t len)
652 {
653 	struct radius_msg *msg;
654 	struct radius_hdr *hdr;
655 	struct radius_attr_hdr *attr;
656 	size_t msg_len;
657 	unsigned char *pos, *end;
658 
659 	if (data == NULL || len < sizeof(*hdr))
660 		return NULL;
661 
662 	hdr = (struct radius_hdr *) data;
663 
664 	msg_len = be_to_host16(hdr->length);
665 	if (msg_len < sizeof(*hdr) || msg_len > len) {
666 		wpa_printf(MSG_INFO, "RADIUS: Invalid message length");
667 		return NULL;
668 	}
669 
670 	if (msg_len < len) {
671 		wpa_printf(MSG_DEBUG, "RADIUS: Ignored %lu extra bytes after "
672 			   "RADIUS message", (unsigned long) len - msg_len);
673 	}
674 
675 	msg = os_zalloc(sizeof(*msg));
676 	if (msg == NULL)
677 		return NULL;
678 
679 	msg->buf = wpabuf_alloc_copy(data, msg_len);
680 	if (msg->buf == NULL || radius_msg_initialize(msg)) {
681 		radius_msg_free(msg);
682 		return NULL;
683 	}
684 	msg->hdr = wpabuf_mhead(msg->buf);
685 
686 	/* parse attributes */
687 	pos = wpabuf_mhead_u8(msg->buf) + sizeof(struct radius_hdr);
688 	end = wpabuf_mhead_u8(msg->buf) + wpabuf_len(msg->buf);
689 	while (pos < end) {
690 		if ((size_t) (end - pos) < sizeof(*attr))
691 			goto fail;
692 
693 		attr = (struct radius_attr_hdr *) pos;
694 
695 		if (pos + attr->length > end || attr->length < sizeof(*attr))
696 			goto fail;
697 
698 		/* TODO: check that attr->length is suitable for attr->type */
699 
700 		if (radius_msg_add_attr_to_array(msg, attr))
701 			goto fail;
702 
703 		pos += attr->length;
704 	}
705 
706 	return msg;
707 
708  fail:
709 	radius_msg_free(msg);
710 	return NULL;
711 }
712 
713 
radius_msg_add_eap(struct radius_msg * msg,const u8 * data,size_t data_len)714 int radius_msg_add_eap(struct radius_msg *msg, const u8 *data, size_t data_len)
715 {
716 	const u8 *pos = data;
717 	size_t left = data_len;
718 
719 	while (left > 0) {
720 		int len;
721 		if (left > RADIUS_MAX_ATTR_LEN)
722 			len = RADIUS_MAX_ATTR_LEN;
723 		else
724 			len = left;
725 
726 		if (!radius_msg_add_attr(msg, RADIUS_ATTR_EAP_MESSAGE,
727 					 pos, len))
728 			return 0;
729 
730 		pos += len;
731 		left -= len;
732 	}
733 
734 	return 1;
735 }
736 
737 
radius_msg_get_eap(struct radius_msg * msg)738 struct wpabuf * radius_msg_get_eap(struct radius_msg *msg)
739 {
740 	struct wpabuf *eap;
741 	size_t len, i;
742 	struct radius_attr_hdr *attr;
743 
744 	if (msg == NULL)
745 		return NULL;
746 
747 	len = 0;
748 	for (i = 0; i < msg->attr_used; i++) {
749 		attr = radius_get_attr_hdr(msg, i);
750 		if (attr->type == RADIUS_ATTR_EAP_MESSAGE &&
751 		    attr->length > sizeof(struct radius_attr_hdr))
752 			len += attr->length - sizeof(struct radius_attr_hdr);
753 	}
754 
755 	if (len == 0)
756 		return NULL;
757 
758 	eap = wpabuf_alloc(len);
759 	if (eap == NULL)
760 		return NULL;
761 
762 	for (i = 0; i < msg->attr_used; i++) {
763 		attr = radius_get_attr_hdr(msg, i);
764 		if (attr->type == RADIUS_ATTR_EAP_MESSAGE &&
765 		    attr->length > sizeof(struct radius_attr_hdr)) {
766 			int flen = attr->length - sizeof(*attr);
767 			wpabuf_put_data(eap, attr + 1, flen);
768 		}
769 	}
770 
771 	return eap;
772 }
773 
774 
radius_msg_verify_msg_auth(struct radius_msg * msg,const u8 * secret,size_t secret_len,const u8 * req_auth)775 int radius_msg_verify_msg_auth(struct radius_msg *msg, const u8 *secret,
776 			       size_t secret_len, const u8 *req_auth)
777 {
778 	u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
779 	u8 orig_authenticator[16];
780 	struct radius_attr_hdr *attr = NULL, *tmp;
781 	size_t i;
782 
783 	for (i = 0; i < msg->attr_used; i++) {
784 		tmp = radius_get_attr_hdr(msg, i);
785 		if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
786 			if (attr != NULL) {
787 				wpa_printf(MSG_INFO, "Multiple Message-Authenticator attributes in RADIUS message");
788 				return 1;
789 			}
790 			attr = tmp;
791 		}
792 	}
793 
794 	if (attr == NULL) {
795 		wpa_printf(MSG_INFO, "No Message-Authenticator attribute found");
796 		return 1;
797 	}
798 
799 	os_memcpy(orig, attr + 1, MD5_MAC_LEN);
800 	os_memset(attr + 1, 0, MD5_MAC_LEN);
801 	if (req_auth) {
802 		os_memcpy(orig_authenticator, msg->hdr->authenticator,
803 			  sizeof(orig_authenticator));
804 		os_memcpy(msg->hdr->authenticator, req_auth,
805 			  sizeof(msg->hdr->authenticator));
806 	}
807 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
808 		 wpabuf_len(msg->buf), auth);
809 	os_memcpy(attr + 1, orig, MD5_MAC_LEN);
810 	if (req_auth) {
811 		os_memcpy(msg->hdr->authenticator, orig_authenticator,
812 			  sizeof(orig_authenticator));
813 	}
814 
815 	if (os_memcmp_const(orig, auth, MD5_MAC_LEN) != 0) {
816 		wpa_printf(MSG_INFO, "Invalid Message-Authenticator!");
817 		return 1;
818 	}
819 
820 	return 0;
821 }
822 
823 
radius_msg_verify(struct radius_msg * msg,const u8 * secret,size_t secret_len,struct radius_msg * sent_msg,int auth)824 int radius_msg_verify(struct radius_msg *msg, const u8 *secret,
825 		      size_t secret_len, struct radius_msg *sent_msg, int auth)
826 {
827 	const u8 *addr[4];
828 	size_t len[4];
829 	u8 hash[MD5_MAC_LEN];
830 
831 	if (sent_msg == NULL) {
832 		wpa_printf(MSG_INFO, "No matching Access-Request message found");
833 		return 1;
834 	}
835 
836 	if (auth &&
837 	    radius_msg_verify_msg_auth(msg, secret, secret_len,
838 				       sent_msg->hdr->authenticator)) {
839 		return 1;
840 	}
841 
842 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
843 	addr[0] = (u8 *) msg->hdr;
844 	len[0] = 1 + 1 + 2;
845 	addr[1] = sent_msg->hdr->authenticator;
846 	len[1] = MD5_MAC_LEN;
847 	addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr);
848 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
849 	addr[3] = secret;
850 	len[3] = secret_len;
851 	md5_vector(4, addr, len, hash);
852 	if (os_memcmp_const(hash, msg->hdr->authenticator, MD5_MAC_LEN) != 0) {
853 		wpa_printf(MSG_INFO, "Response Authenticator invalid!");
854 		return 1;
855 	}
856 
857 	return 0;
858 }
859 
860 
radius_msg_copy_attr(struct radius_msg * dst,struct radius_msg * src,u8 type)861 int radius_msg_copy_attr(struct radius_msg *dst, struct radius_msg *src,
862 			 u8 type)
863 {
864 	struct radius_attr_hdr *attr;
865 	size_t i;
866 	int count = 0;
867 
868 	for (i = 0; i < src->attr_used; i++) {
869 		attr = radius_get_attr_hdr(src, i);
870 		if (attr->type == type && attr->length >= sizeof(*attr)) {
871 			if (!radius_msg_add_attr(dst, type, (u8 *) (attr + 1),
872 						 attr->length - sizeof(*attr)))
873 				return -1;
874 			count++;
875 		}
876 	}
877 
878 	return count;
879 }
880 
881 
882 /* Create Request Authenticator. The value should be unique over the lifetime
883  * of the shared secret between authenticator and authentication server.
884  * Use one-way MD5 hash calculated from current timestamp and some data given
885  * by the caller. */
radius_msg_make_authenticator(struct radius_msg * msg,const u8 * data,size_t len)886 void radius_msg_make_authenticator(struct radius_msg *msg,
887 				   const u8 *data, size_t len)
888 {
889 	struct os_time tv;
890 	long int l;
891 	const u8 *addr[3];
892 	size_t elen[3];
893 
894 	os_get_time(&tv);
895 	l = os_random();
896 	addr[0] = (u8 *) &tv;
897 	elen[0] = sizeof(tv);
898 	addr[1] = data;
899 	elen[1] = len;
900 	addr[2] = (u8 *) &l;
901 	elen[2] = sizeof(l);
902 	md5_vector(3, addr, elen, msg->hdr->authenticator);
903 }
904 
905 
906 /* Get Vendor-specific RADIUS Attribute from a parsed RADIUS message.
907  * Returns the Attribute payload and sets alen to indicate the length of the
908  * payload if a vendor attribute with subtype is found, otherwise returns NULL.
909  * The returned payload is allocated with os_malloc() and caller must free it
910  * by calling os_free().
911  */
radius_msg_get_vendor_attr(struct radius_msg * msg,u32 vendor,u8 subtype,size_t * alen)912 static u8 *radius_msg_get_vendor_attr(struct radius_msg *msg, u32 vendor,
913 				      u8 subtype, size_t *alen)
914 {
915 	u8 *data, *pos;
916 	size_t i, len;
917 
918 	if (msg == NULL)
919 		return NULL;
920 
921 	for (i = 0; i < msg->attr_used; i++) {
922 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
923 		size_t left;
924 		u32 vendor_id;
925 		struct radius_attr_vendor *vhdr;
926 
927 		if (attr->type != RADIUS_ATTR_VENDOR_SPECIFIC ||
928 		    attr->length < sizeof(*attr))
929 			continue;
930 
931 		left = attr->length - sizeof(*attr);
932 		if (left < 4)
933 			continue;
934 
935 		pos = (u8 *) (attr + 1);
936 
937 		os_memcpy(&vendor_id, pos, 4);
938 		pos += 4;
939 		left -= 4;
940 
941 		if (ntohl(vendor_id) != vendor)
942 			continue;
943 
944 		while (left >= sizeof(*vhdr)) {
945 			vhdr = (struct radius_attr_vendor *) pos;
946 			if (vhdr->vendor_length > left ||
947 			    vhdr->vendor_length < sizeof(*vhdr)) {
948 				left = 0;
949 				break;
950 			}
951 			if (vhdr->vendor_type != subtype) {
952 				pos += vhdr->vendor_length;
953 				left -= vhdr->vendor_length;
954 				continue;
955 			}
956 
957 			len = vhdr->vendor_length - sizeof(*vhdr);
958 			data = os_malloc(len);
959 			if (data == NULL)
960 				return NULL;
961 			os_memcpy(data, pos + sizeof(*vhdr), len);
962 			if (alen)
963 				*alen = len;
964 			return data;
965 		}
966 	}
967 
968 	return NULL;
969 }
970 
971 
decrypt_ms_key(const u8 * key,size_t len,const u8 * req_authenticator,const u8 * secret,size_t secret_len,size_t * reslen)972 static u8 * decrypt_ms_key(const u8 *key, size_t len,
973 			   const u8 *req_authenticator,
974 			   const u8 *secret, size_t secret_len, size_t *reslen)
975 {
976 	u8 *plain, *ppos, *res;
977 	const u8 *pos;
978 	size_t left, plen;
979 	u8 hash[MD5_MAC_LEN];
980 	int i, first = 1;
981 	const u8 *addr[3];
982 	size_t elen[3];
983 
984 	/* key: 16-bit salt followed by encrypted key info */
985 
986 	if (len < 2 + 16)
987 		return NULL;
988 
989 	pos = key + 2;
990 	left = len - 2;
991 	if (left % 16) {
992 		wpa_printf(MSG_INFO, "Invalid ms key len %lu",
993 			   (unsigned long) left);
994 		return NULL;
995 	}
996 
997 	plen = left;
998 	ppos = plain = os_malloc(plen);
999 	if (plain == NULL)
1000 		return NULL;
1001 	plain[0] = 0;
1002 
1003 	while (left > 0) {
1004 		/* b(1) = MD5(Secret + Request-Authenticator + Salt)
1005 		 * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
1006 
1007 		addr[0] = secret;
1008 		elen[0] = secret_len;
1009 		if (first) {
1010 			addr[1] = req_authenticator;
1011 			elen[1] = MD5_MAC_LEN;
1012 			addr[2] = key;
1013 			elen[2] = 2; /* Salt */
1014 		} else {
1015 			addr[1] = pos - MD5_MAC_LEN;
1016 			elen[1] = MD5_MAC_LEN;
1017 		}
1018 		md5_vector(first ? 3 : 2, addr, elen, hash);
1019 		first = 0;
1020 
1021 		for (i = 0; i < MD5_MAC_LEN; i++)
1022 			*ppos++ = *pos++ ^ hash[i];
1023 		left -= MD5_MAC_LEN;
1024 	}
1025 
1026 	if (plain[0] == 0 || plain[0] > plen - 1) {
1027 		wpa_printf(MSG_INFO, "Failed to decrypt MPPE key");
1028 		os_free(plain);
1029 		return NULL;
1030 	}
1031 
1032 	res = os_malloc(plain[0]);
1033 	if (res == NULL) {
1034 		os_free(plain);
1035 		return NULL;
1036 	}
1037 	os_memcpy(res, plain + 1, plain[0]);
1038 	if (reslen)
1039 		*reslen = plain[0];
1040 	os_free(plain);
1041 	return res;
1042 }
1043 
1044 
encrypt_ms_key(const u8 * key,size_t key_len,u16 salt,const u8 * req_authenticator,const u8 * secret,size_t secret_len,u8 * ebuf,size_t * elen)1045 static void encrypt_ms_key(const u8 *key, size_t key_len, u16 salt,
1046 			   const u8 *req_authenticator,
1047 			   const u8 *secret, size_t secret_len,
1048 			   u8 *ebuf, size_t *elen)
1049 {
1050 	int i, len, first = 1;
1051 	u8 hash[MD5_MAC_LEN], saltbuf[2], *pos;
1052 	const u8 *addr[3];
1053 	size_t _len[3];
1054 
1055 	WPA_PUT_BE16(saltbuf, salt);
1056 
1057 	len = 1 + key_len;
1058 	if (len & 0x0f) {
1059 		len = (len & 0xf0) + 16;
1060 	}
1061 	os_memset(ebuf, 0, len);
1062 	ebuf[0] = key_len;
1063 	os_memcpy(ebuf + 1, key, key_len);
1064 
1065 	*elen = len;
1066 
1067 	pos = ebuf;
1068 	while (len > 0) {
1069 		/* b(1) = MD5(Secret + Request-Authenticator + Salt)
1070 		 * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
1071 		addr[0] = secret;
1072 		_len[0] = secret_len;
1073 		if (first) {
1074 			addr[1] = req_authenticator;
1075 			_len[1] = MD5_MAC_LEN;
1076 			addr[2] = saltbuf;
1077 			_len[2] = sizeof(saltbuf);
1078 		} else {
1079 			addr[1] = pos - MD5_MAC_LEN;
1080 			_len[1] = MD5_MAC_LEN;
1081 		}
1082 		md5_vector(first ? 3 : 2, addr, _len, hash);
1083 		first = 0;
1084 
1085 		for (i = 0; i < MD5_MAC_LEN; i++)
1086 			*pos++ ^= hash[i];
1087 
1088 		len -= MD5_MAC_LEN;
1089 	}
1090 }
1091 
1092 
1093 struct radius_ms_mppe_keys *
radius_msg_get_ms_keys(struct radius_msg * msg,struct radius_msg * sent_msg,const u8 * secret,size_t secret_len)1094 radius_msg_get_ms_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
1095 		       const u8 *secret, size_t secret_len)
1096 {
1097 	u8 *key;
1098 	size_t keylen;
1099 	struct radius_ms_mppe_keys *keys;
1100 
1101 	if (msg == NULL || sent_msg == NULL)
1102 		return NULL;
1103 
1104 	keys = os_zalloc(sizeof(*keys));
1105 	if (keys == NULL)
1106 		return NULL;
1107 
1108 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
1109 					 RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY,
1110 					 &keylen);
1111 	if (key) {
1112 		keys->send = decrypt_ms_key(key, keylen,
1113 					    sent_msg->hdr->authenticator,
1114 					    secret, secret_len,
1115 					    &keys->send_len);
1116 		os_free(key);
1117 	}
1118 
1119 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
1120 					 RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY,
1121 					 &keylen);
1122 	if (key) {
1123 		keys->recv = decrypt_ms_key(key, keylen,
1124 					    sent_msg->hdr->authenticator,
1125 					    secret, secret_len,
1126 					    &keys->recv_len);
1127 		os_free(key);
1128 	}
1129 
1130 	return keys;
1131 }
1132 
1133 
1134 struct radius_ms_mppe_keys *
radius_msg_get_cisco_keys(struct radius_msg * msg,struct radius_msg * sent_msg,const u8 * secret,size_t secret_len)1135 radius_msg_get_cisco_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
1136 			  const u8 *secret, size_t secret_len)
1137 {
1138 	u8 *key;
1139 	size_t keylen;
1140 	struct radius_ms_mppe_keys *keys;
1141 
1142 	if (msg == NULL || sent_msg == NULL)
1143 		return NULL;
1144 
1145 	keys = os_zalloc(sizeof(*keys));
1146 	if (keys == NULL)
1147 		return NULL;
1148 
1149 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_CISCO,
1150 					 RADIUS_CISCO_AV_PAIR, &keylen);
1151 	if (key && keylen == 51 &&
1152 	    os_memcmp(key, "leap:session-key=", 17) == 0) {
1153 		keys->recv = decrypt_ms_key(key + 17, keylen - 17,
1154 					    sent_msg->hdr->authenticator,
1155 					    secret, secret_len,
1156 					    &keys->recv_len);
1157 	}
1158 	os_free(key);
1159 
1160 	return keys;
1161 }
1162 
1163 
radius_msg_add_mppe_keys(struct radius_msg * msg,const u8 * req_authenticator,const u8 * secret,size_t secret_len,const u8 * send_key,size_t send_key_len,const u8 * recv_key,size_t recv_key_len)1164 int radius_msg_add_mppe_keys(struct radius_msg *msg,
1165 			     const u8 *req_authenticator,
1166 			     const u8 *secret, size_t secret_len,
1167 			     const u8 *send_key, size_t send_key_len,
1168 			     const u8 *recv_key, size_t recv_key_len)
1169 {
1170 	struct radius_attr_hdr *attr;
1171 	u32 vendor_id = htonl(RADIUS_VENDOR_ID_MICROSOFT);
1172 	u8 *buf;
1173 	struct radius_attr_vendor *vhdr;
1174 	u8 *pos;
1175 	size_t elen;
1176 	int hlen;
1177 	u16 salt;
1178 
1179 	hlen = sizeof(vendor_id) + sizeof(*vhdr) + 2;
1180 
1181 	/* MS-MPPE-Send-Key */
1182 	buf = os_malloc(hlen + send_key_len + 16);
1183 	if (buf == NULL) {
1184 		return 0;
1185 	}
1186 	pos = buf;
1187 	os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1188 	pos += sizeof(vendor_id);
1189 	vhdr = (struct radius_attr_vendor *) pos;
1190 	vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY;
1191 	pos = (u8 *) (vhdr + 1);
1192 	salt = os_random() | 0x8000;
1193 	WPA_PUT_BE16(pos, salt);
1194 	pos += 2;
1195 	encrypt_ms_key(send_key, send_key_len, salt, req_authenticator, secret,
1196 		       secret_len, pos, &elen);
1197 	vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1198 
1199 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1200 				   buf, hlen + elen);
1201 	os_free(buf);
1202 	if (attr == NULL) {
1203 		return 0;
1204 	}
1205 
1206 	/* MS-MPPE-Recv-Key */
1207 	buf = os_malloc(hlen + send_key_len + 16);
1208 	if (buf == NULL) {
1209 		return 0;
1210 	}
1211 	pos = buf;
1212 	os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1213 	pos += sizeof(vendor_id);
1214 	vhdr = (struct radius_attr_vendor *) pos;
1215 	vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY;
1216 	pos = (u8 *) (vhdr + 1);
1217 	salt ^= 1;
1218 	WPA_PUT_BE16(pos, salt);
1219 	pos += 2;
1220 	encrypt_ms_key(recv_key, recv_key_len, salt, req_authenticator, secret,
1221 		       secret_len, pos, &elen);
1222 	vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1223 
1224 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1225 				   buf, hlen + elen);
1226 	os_free(buf);
1227 	if (attr == NULL) {
1228 		return 0;
1229 	}
1230 
1231 	return 1;
1232 }
1233 
1234 
radius_msg_add_wfa(struct radius_msg * msg,u8 subtype,const u8 * data,size_t len)1235 int radius_msg_add_wfa(struct radius_msg *msg, u8 subtype, const u8 *data,
1236 		       size_t len)
1237 {
1238 	struct radius_attr_hdr *attr;
1239 	u8 *buf, *pos;
1240 	size_t alen;
1241 
1242 	alen = 4 + 2 + len;
1243 	buf = os_malloc(alen);
1244 	if (buf == NULL)
1245 		return 0;
1246 	pos = buf;
1247 	WPA_PUT_BE32(pos, RADIUS_VENDOR_ID_WFA);
1248 	pos += 4;
1249 	*pos++ = subtype;
1250 	*pos++ = 2 + len;
1251 	os_memcpy(pos, data, len);
1252 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1253 				   buf, alen);
1254 	os_free(buf);
1255 	if (attr == NULL)
1256 		return 0;
1257 
1258 	return 1;
1259 }
1260 
1261 
radius_user_password_hide(struct radius_msg * msg,const u8 * data,size_t data_len,const u8 * secret,size_t secret_len,u8 * buf,size_t buf_len)1262 int radius_user_password_hide(struct radius_msg *msg,
1263 			      const u8 *data, size_t data_len,
1264 			      const u8 *secret, size_t secret_len,
1265 			      u8 *buf, size_t buf_len)
1266 {
1267 	size_t padlen, i, pos;
1268 	const u8 *addr[2];
1269 	size_t len[2];
1270 	u8 hash[16];
1271 
1272 	if (data_len + 16 > buf_len)
1273 		return -1;
1274 
1275 	os_memcpy(buf, data, data_len);
1276 
1277 	padlen = data_len % 16;
1278 	if (padlen && data_len < buf_len) {
1279 		padlen = 16 - padlen;
1280 		os_memset(buf + data_len, 0, padlen);
1281 		buf_len = data_len + padlen;
1282 	} else {
1283 		buf_len = data_len;
1284 	}
1285 
1286 	addr[0] = secret;
1287 	len[0] = secret_len;
1288 	addr[1] = msg->hdr->authenticator;
1289 	len[1] = 16;
1290 	md5_vector(2, addr, len, hash);
1291 
1292 	for (i = 0; i < 16; i++)
1293 		buf[i] ^= hash[i];
1294 	pos = 16;
1295 
1296 	while (pos < buf_len) {
1297 		addr[0] = secret;
1298 		len[0] = secret_len;
1299 		addr[1] = &buf[pos - 16];
1300 		len[1] = 16;
1301 		md5_vector(2, addr, len, hash);
1302 
1303 		for (i = 0; i < 16; i++)
1304 			buf[pos + i] ^= hash[i];
1305 
1306 		pos += 16;
1307 	}
1308 
1309 	return buf_len;
1310 }
1311 
1312 
1313 /* Add User-Password attribute to a RADIUS message and encrypt it as specified
1314  * in RFC 2865, Chap. 5.2 */
1315 struct radius_attr_hdr *
radius_msg_add_attr_user_password(struct radius_msg * msg,const u8 * data,size_t data_len,const u8 * secret,size_t secret_len)1316 radius_msg_add_attr_user_password(struct radius_msg *msg,
1317 				  const u8 *data, size_t data_len,
1318 				  const u8 *secret, size_t secret_len)
1319 {
1320 	u8 buf[128];
1321 	int res;
1322 
1323 	res = radius_user_password_hide(msg, data, data_len,
1324 					secret, secret_len, buf, sizeof(buf));
1325 	if (res < 0)
1326 		return NULL;
1327 
1328 	return radius_msg_add_attr(msg, RADIUS_ATTR_USER_PASSWORD,
1329 				   buf, res);
1330 }
1331 
1332 
radius_msg_get_attr(struct radius_msg * msg,u8 type,u8 * buf,size_t len)1333 int radius_msg_get_attr(struct radius_msg *msg, u8 type, u8 *buf, size_t len)
1334 {
1335 	struct radius_attr_hdr *attr = NULL, *tmp;
1336 	size_t i, dlen;
1337 
1338 	for (i = 0; i < msg->attr_used; i++) {
1339 		tmp = radius_get_attr_hdr(msg, i);
1340 		if (tmp->type == type) {
1341 			attr = tmp;
1342 			break;
1343 		}
1344 	}
1345 
1346 	if (!attr || attr->length < sizeof(*attr))
1347 		return -1;
1348 
1349 	dlen = attr->length - sizeof(*attr);
1350 	if (buf)
1351 		os_memcpy(buf, (attr + 1), dlen > len ? len : dlen);
1352 	return dlen;
1353 }
1354 
1355 
radius_msg_get_attr_ptr(struct radius_msg * msg,u8 type,u8 ** buf,size_t * len,const u8 * start)1356 int radius_msg_get_attr_ptr(struct radius_msg *msg, u8 type, u8 **buf,
1357 			    size_t *len, const u8 *start)
1358 {
1359 	size_t i;
1360 	struct radius_attr_hdr *attr = NULL, *tmp;
1361 
1362 	for (i = 0; i < msg->attr_used; i++) {
1363 		tmp = radius_get_attr_hdr(msg, i);
1364 		if (tmp->type == type &&
1365 		    (start == NULL || (u8 *) tmp > start)) {
1366 			attr = tmp;
1367 			break;
1368 		}
1369 	}
1370 
1371 	if (!attr || attr->length < sizeof(*attr))
1372 		return -1;
1373 
1374 	*buf = (u8 *) (attr + 1);
1375 	*len = attr->length - sizeof(*attr);
1376 	return 0;
1377 }
1378 
1379 
radius_msg_count_attr(struct radius_msg * msg,u8 type,int min_len)1380 int radius_msg_count_attr(struct radius_msg *msg, u8 type, int min_len)
1381 {
1382 	size_t i;
1383 	int count;
1384 
1385 	for (count = 0, i = 0; i < msg->attr_used; i++) {
1386 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
1387 		if (attr->type == type &&
1388 		    attr->length >= sizeof(struct radius_attr_hdr) + min_len)
1389 			count++;
1390 	}
1391 
1392 	return count;
1393 }
1394 
1395 
1396 struct radius_tunnel_attrs {
1397 	int tag_used;
1398 	int type; /* Tunnel-Type */
1399 	int medium_type; /* Tunnel-Medium-Type */
1400 	int vlanid;
1401 };
1402 
1403 
1404 /**
1405  * radius_msg_get_vlanid - Parse RADIUS attributes for VLAN tunnel information
1406  * @msg: RADIUS message
1407  * Returns: VLAN ID for the first tunnel configuration of -1 if none is found
1408  */
radius_msg_get_vlanid(struct radius_msg * msg)1409 int radius_msg_get_vlanid(struct radius_msg *msg)
1410 {
1411 	struct radius_tunnel_attrs tunnel[RADIUS_TUNNEL_TAGS], *tun;
1412 	size_t i;
1413 	struct radius_attr_hdr *attr = NULL;
1414 	const u8 *data;
1415 	char buf[10];
1416 	size_t dlen;
1417 
1418 	os_memset(&tunnel, 0, sizeof(tunnel));
1419 
1420 	for (i = 0; i < msg->attr_used; i++) {
1421 		attr = radius_get_attr_hdr(msg, i);
1422 		if (attr->length < sizeof(*attr))
1423 			return -1;
1424 		data = (const u8 *) (attr + 1);
1425 		dlen = attr->length - sizeof(*attr);
1426 		if (attr->length < 3)
1427 			continue;
1428 		if (data[0] >= RADIUS_TUNNEL_TAGS)
1429 			tun = &tunnel[0];
1430 		else
1431 			tun = &tunnel[data[0]];
1432 
1433 		switch (attr->type) {
1434 		case RADIUS_ATTR_TUNNEL_TYPE:
1435 			if (attr->length != 6)
1436 				break;
1437 			tun->tag_used++;
1438 			tun->type = WPA_GET_BE24(data + 1);
1439 			break;
1440 		case RADIUS_ATTR_TUNNEL_MEDIUM_TYPE:
1441 			if (attr->length != 6)
1442 				break;
1443 			tun->tag_used++;
1444 			tun->medium_type = WPA_GET_BE24(data + 1);
1445 			break;
1446 		case RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID:
1447 			if (data[0] < RADIUS_TUNNEL_TAGS) {
1448 				data++;
1449 				dlen--;
1450 			}
1451 			if (dlen >= sizeof(buf))
1452 				break;
1453 			os_memcpy(buf, data, dlen);
1454 			buf[dlen] = '\0';
1455 			tun->tag_used++;
1456 			tun->vlanid = atoi(buf);
1457 			break;
1458 		}
1459 	}
1460 
1461 	for (i = 0; i < RADIUS_TUNNEL_TAGS; i++) {
1462 		tun = &tunnel[i];
1463 		if (tun->tag_used &&
1464 		    tun->type == RADIUS_TUNNEL_TYPE_VLAN &&
1465 		    tun->medium_type == RADIUS_TUNNEL_MEDIUM_TYPE_802 &&
1466 		    tun->vlanid > 0)
1467 			return tun->vlanid;
1468 	}
1469 
1470 	return -1;
1471 }
1472 
1473 
1474 /**
1475  * radius_msg_get_tunnel_password - Parse RADIUS attribute Tunnel-Password
1476  * @msg: Received RADIUS message
1477  * @keylen: Length of returned password
1478  * @secret: RADIUS shared secret
1479  * @secret_len: Length of secret
1480  * @sent_msg: Sent RADIUS message
1481  * @n: Number of password attribute to return (starting with 0)
1482  * Returns: Pointer to n-th password (free with os_free) or %NULL
1483  */
radius_msg_get_tunnel_password(struct radius_msg * msg,int * keylen,const u8 * secret,size_t secret_len,struct radius_msg * sent_msg,size_t n)1484 char * radius_msg_get_tunnel_password(struct radius_msg *msg, int *keylen,
1485 				      const u8 *secret, size_t secret_len,
1486 				      struct radius_msg *sent_msg, size_t n)
1487 {
1488 	u8 *buf = NULL;
1489 	size_t buflen;
1490 	const u8 *salt;
1491 	u8 *str;
1492 	const u8 *addr[3];
1493 	size_t len[3];
1494 	u8 hash[16];
1495 	u8 *pos;
1496 	size_t i, j = 0;
1497 	struct radius_attr_hdr *attr;
1498 	const u8 *data;
1499 	size_t dlen;
1500 	const u8 *fdata = NULL; /* points to found item */
1501 	size_t fdlen = -1;
1502 	char *ret = NULL;
1503 
1504 	/* find n-th valid Tunnel-Password attribute */
1505 	for (i = 0; i < msg->attr_used; i++) {
1506 		attr = radius_get_attr_hdr(msg, i);
1507 		if (attr == NULL ||
1508 		    attr->type != RADIUS_ATTR_TUNNEL_PASSWORD) {
1509 			continue;
1510 		}
1511 		if (attr->length <= 5)
1512 			continue;
1513 		data = (const u8 *) (attr + 1);
1514 		dlen = attr->length - sizeof(*attr);
1515 		if (dlen <= 3 || dlen % 16 != 3)
1516 			continue;
1517 		j++;
1518 		if (j <= n)
1519 			continue;
1520 
1521 		fdata = data;
1522 		fdlen = dlen;
1523 		break;
1524 	}
1525 	if (fdata == NULL)
1526 		goto out;
1527 
1528 	/* alloc writable memory for decryption */
1529 	buf = os_malloc(fdlen);
1530 	if (buf == NULL)
1531 		goto out;
1532 	os_memcpy(buf, fdata, fdlen);
1533 	buflen = fdlen;
1534 
1535 	/* init pointers */
1536 	salt = buf + 1;
1537 	str = buf + 3;
1538 
1539 	/* decrypt blocks */
1540 	pos = buf + buflen - 16; /* last block */
1541 	while (pos >= str + 16) { /* all but the first block */
1542 		addr[0] = secret;
1543 		len[0] = secret_len;
1544 		addr[1] = pos - 16;
1545 		len[1] = 16;
1546 		md5_vector(2, addr, len, hash);
1547 
1548 		for (i = 0; i < 16; i++)
1549 			pos[i] ^= hash[i];
1550 
1551 		pos -= 16;
1552 	}
1553 
1554 	/* decrypt first block */
1555 	if (str != pos)
1556 		goto out;
1557 	addr[0] = secret;
1558 	len[0] = secret_len;
1559 	addr[1] = sent_msg->hdr->authenticator;
1560 	len[1] = 16;
1561 	addr[2] = salt;
1562 	len[2] = 2;
1563 	md5_vector(3, addr, len, hash);
1564 
1565 	for (i = 0; i < 16; i++)
1566 		pos[i] ^= hash[i];
1567 
1568 	/* derive plaintext length from first subfield */
1569 	*keylen = (unsigned char) str[0];
1570 	if ((u8 *) (str + *keylen) >= (u8 *) (buf + buflen)) {
1571 		/* decryption error - invalid key length */
1572 		goto out;
1573 	}
1574 	if (*keylen == 0) {
1575 		/* empty password */
1576 		goto out;
1577 	}
1578 
1579 	/* copy passphrase into new buffer */
1580 	ret = os_malloc(*keylen);
1581 	if (ret)
1582 		os_memcpy(ret, str + 1, *keylen);
1583 
1584 out:
1585 	/* return new buffer */
1586 	os_free(buf);
1587 	return ret;
1588 }
1589 
1590 
radius_free_class(struct radius_class_data * c)1591 void radius_free_class(struct radius_class_data *c)
1592 {
1593 	size_t i;
1594 	if (c == NULL)
1595 		return;
1596 	for (i = 0; i < c->count; i++)
1597 		os_free(c->attr[i].data);
1598 	os_free(c->attr);
1599 	c->attr = NULL;
1600 	c->count = 0;
1601 }
1602 
1603 
radius_copy_class(struct radius_class_data * dst,const struct radius_class_data * src)1604 int radius_copy_class(struct radius_class_data *dst,
1605 		      const struct radius_class_data *src)
1606 {
1607 	size_t i;
1608 
1609 	if (src->attr == NULL)
1610 		return 0;
1611 
1612 	dst->attr = os_calloc(src->count, sizeof(struct radius_attr_data));
1613 	if (dst->attr == NULL)
1614 		return -1;
1615 
1616 	dst->count = 0;
1617 
1618 	for (i = 0; i < src->count; i++) {
1619 		dst->attr[i].data = os_malloc(src->attr[i].len);
1620 		if (dst->attr[i].data == NULL)
1621 			break;
1622 		dst->count++;
1623 		os_memcpy(dst->attr[i].data, src->attr[i].data,
1624 			  src->attr[i].len);
1625 		dst->attr[i].len = src->attr[i].len;
1626 	}
1627 
1628 	return 0;
1629 }
1630 
1631 
radius_msg_find_unlisted_attr(struct radius_msg * msg,u8 * attrs)1632 u8 radius_msg_find_unlisted_attr(struct radius_msg *msg, u8 *attrs)
1633 {
1634 	size_t i, j;
1635 	struct radius_attr_hdr *attr;
1636 
1637 	for (i = 0; i < msg->attr_used; i++) {
1638 		attr = radius_get_attr_hdr(msg, i);
1639 
1640 		for (j = 0; attrs[j]; j++) {
1641 			if (attr->type == attrs[j])
1642 				break;
1643 		}
1644 
1645 		if (attrs[j] == 0)
1646 			return attr->type; /* unlisted attr */
1647 	}
1648 
1649 	return 0;
1650 }
1651