1 /*
2  * RADIUS message processing
3  * Copyright (c) 2002-2009, 2011-2015, 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 const 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_SERVICE_TYPE, "Service-Type", RADIUS_ATTR_INT32 },
177 	{ RADIUS_ATTR_FRAMED_IP_ADDRESS, "Framed-IP-Address", RADIUS_ATTR_IP },
178 	{ RADIUS_ATTR_FRAMED_MTU, "Framed-MTU", RADIUS_ATTR_INT32 },
179 	{ RADIUS_ATTR_REPLY_MESSAGE, "Reply-Message", RADIUS_ATTR_TEXT },
180 	{ RADIUS_ATTR_STATE, "State", RADIUS_ATTR_UNDIST },
181 	{ RADIUS_ATTR_CLASS, "Class", RADIUS_ATTR_UNDIST },
182 	{ RADIUS_ATTR_VENDOR_SPECIFIC, "Vendor-Specific", RADIUS_ATTR_UNDIST },
183 	{ RADIUS_ATTR_SESSION_TIMEOUT, "Session-Timeout", RADIUS_ATTR_INT32 },
184 	{ RADIUS_ATTR_IDLE_TIMEOUT, "Idle-Timeout", RADIUS_ATTR_INT32 },
185 	{ RADIUS_ATTR_TERMINATION_ACTION, "Termination-Action",
186 	  RADIUS_ATTR_INT32 },
187 	{ RADIUS_ATTR_CALLED_STATION_ID, "Called-Station-Id",
188 	  RADIUS_ATTR_TEXT },
189 	{ RADIUS_ATTR_CALLING_STATION_ID, "Calling-Station-Id",
190 	  RADIUS_ATTR_TEXT },
191 	{ RADIUS_ATTR_NAS_IDENTIFIER, "NAS-Identifier", RADIUS_ATTR_TEXT },
192 	{ RADIUS_ATTR_PROXY_STATE, "Proxy-State", RADIUS_ATTR_UNDIST },
193 	{ RADIUS_ATTR_ACCT_STATUS_TYPE, "Acct-Status-Type",
194 	  RADIUS_ATTR_INT32 },
195 	{ RADIUS_ATTR_ACCT_DELAY_TIME, "Acct-Delay-Time", RADIUS_ATTR_INT32 },
196 	{ RADIUS_ATTR_ACCT_INPUT_OCTETS, "Acct-Input-Octets",
197 	  RADIUS_ATTR_INT32 },
198 	{ RADIUS_ATTR_ACCT_OUTPUT_OCTETS, "Acct-Output-Octets",
199 	  RADIUS_ATTR_INT32 },
200 	{ RADIUS_ATTR_ACCT_SESSION_ID, "Acct-Session-Id", RADIUS_ATTR_TEXT },
201 	{ RADIUS_ATTR_ACCT_AUTHENTIC, "Acct-Authentic", RADIUS_ATTR_INT32 },
202 	{ RADIUS_ATTR_ACCT_SESSION_TIME, "Acct-Session-Time",
203 	  RADIUS_ATTR_INT32 },
204 	{ RADIUS_ATTR_ACCT_INPUT_PACKETS, "Acct-Input-Packets",
205 	  RADIUS_ATTR_INT32 },
206 	{ RADIUS_ATTR_ACCT_OUTPUT_PACKETS, "Acct-Output-Packets",
207 	  RADIUS_ATTR_INT32 },
208 	{ RADIUS_ATTR_ACCT_TERMINATE_CAUSE, "Acct-Terminate-Cause",
209 	  RADIUS_ATTR_INT32 },
210 	{ RADIUS_ATTR_ACCT_MULTI_SESSION_ID, "Acct-Multi-Session-Id",
211 	  RADIUS_ATTR_TEXT },
212 	{ RADIUS_ATTR_ACCT_LINK_COUNT, "Acct-Link-Count", RADIUS_ATTR_INT32 },
213 	{ RADIUS_ATTR_ACCT_INPUT_GIGAWORDS, "Acct-Input-Gigawords",
214 	  RADIUS_ATTR_INT32 },
215 	{ RADIUS_ATTR_ACCT_OUTPUT_GIGAWORDS, "Acct-Output-Gigawords",
216 	  RADIUS_ATTR_INT32 },
217 	{ RADIUS_ATTR_EVENT_TIMESTAMP, "Event-Timestamp",
218 	  RADIUS_ATTR_INT32 },
219 	{ RADIUS_ATTR_EGRESS_VLANID, "EGRESS-VLANID", RADIUS_ATTR_HEXDUMP },
220 	{ RADIUS_ATTR_NAS_PORT_TYPE, "NAS-Port-Type", RADIUS_ATTR_INT32 },
221 	{ RADIUS_ATTR_TUNNEL_TYPE, "Tunnel-Type", RADIUS_ATTR_HEXDUMP },
222 	{ RADIUS_ATTR_TUNNEL_MEDIUM_TYPE, "Tunnel-Medium-Type",
223 	  RADIUS_ATTR_HEXDUMP },
224 	{ RADIUS_ATTR_TUNNEL_PASSWORD, "Tunnel-Password",
225 	  RADIUS_ATTR_UNDIST },
226 	{ RADIUS_ATTR_CONNECT_INFO, "Connect-Info", RADIUS_ATTR_TEXT },
227 	{ RADIUS_ATTR_EAP_MESSAGE, "EAP-Message", RADIUS_ATTR_UNDIST },
228 	{ RADIUS_ATTR_MESSAGE_AUTHENTICATOR, "Message-Authenticator",
229 	  RADIUS_ATTR_UNDIST },
230 	{ RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID, "Tunnel-Private-Group-Id",
231 	  RADIUS_ATTR_HEXDUMP },
232 	{ RADIUS_ATTR_ACCT_INTERIM_INTERVAL, "Acct-Interim-Interval",
233 	  RADIUS_ATTR_INT32 },
234 	{ RADIUS_ATTR_CHARGEABLE_USER_IDENTITY, "Chargeable-User-Identity",
235 	  RADIUS_ATTR_TEXT },
236 	{ RADIUS_ATTR_NAS_IPV6_ADDRESS, "NAS-IPv6-Address", RADIUS_ATTR_IPV6 },
237 	{ RADIUS_ATTR_ERROR_CAUSE, "Error-Cause", RADIUS_ATTR_INT32 },
238 	{ RADIUS_ATTR_EAP_KEY_NAME, "EAP-Key-Name", RADIUS_ATTR_HEXDUMP },
239 	{ RADIUS_ATTR_OPERATOR_NAME, "Operator-Name", RADIUS_ATTR_TEXT },
240 	{ RADIUS_ATTR_LOCATION_INFO, "Location-Information",
241 	  RADIUS_ATTR_HEXDUMP },
242 	{ RADIUS_ATTR_LOCATION_DATA, "Location-Data", RADIUS_ATTR_HEXDUMP },
243 	{ RADIUS_ATTR_BASIC_LOCATION_POLICY_RULES,
244 	  "Basic-Location-Policy-Rules", RADIUS_ATTR_HEXDUMP },
245 	{ RADIUS_ATTR_EXTENDED_LOCATION_POLICY_RULES,
246 	  "Extended-Location-Policy-Rules", RADIUS_ATTR_HEXDUMP },
247 	{ RADIUS_ATTR_LOCATION_CAPABLE, "Location-Capable", RADIUS_ATTR_INT32 },
248 	{ RADIUS_ATTR_REQUESTED_LOCATION_INFO, "Requested-Location-Info",
249 	  RADIUS_ATTR_INT32 },
250 	{ RADIUS_ATTR_MOBILITY_DOMAIN_ID, "Mobility-Domain-Id",
251 	  RADIUS_ATTR_INT32 },
252 	{ RADIUS_ATTR_WLAN_HESSID, "WLAN-HESSID", RADIUS_ATTR_TEXT },
253 	{ RADIUS_ATTR_WLAN_PAIRWISE_CIPHER, "WLAN-Pairwise-Cipher",
254 	  RADIUS_ATTR_HEXDUMP },
255 	{ RADIUS_ATTR_WLAN_GROUP_CIPHER, "WLAN-Group-Cipher",
256 	  RADIUS_ATTR_HEXDUMP },
257 	{ RADIUS_ATTR_WLAN_AKM_SUITE, "WLAN-AKM-Suite",
258 	  RADIUS_ATTR_HEXDUMP },
259 	{ RADIUS_ATTR_WLAN_GROUP_MGMT_CIPHER, "WLAN-Group-Mgmt-Pairwise-Cipher",
260 	  RADIUS_ATTR_HEXDUMP },
261 };
262 #define RADIUS_ATTRS ARRAY_SIZE(radius_attrs)
263 
264 
radius_get_attr_type(u8 type)265 static const struct radius_attr_type *radius_get_attr_type(u8 type)
266 {
267 	size_t i;
268 
269 	for (i = 0; i < RADIUS_ATTRS; i++) {
270 		if (type == radius_attrs[i].type)
271 			return &radius_attrs[i];
272 	}
273 
274 	return NULL;
275 }
276 
277 
radius_msg_dump_attr(struct radius_attr_hdr * hdr)278 static void radius_msg_dump_attr(struct radius_attr_hdr *hdr)
279 {
280 	const struct radius_attr_type *attr;
281 	int len;
282 	unsigned char *pos;
283 	char buf[1000];
284 
285 	attr = radius_get_attr_type(hdr->type);
286 
287 	wpa_printf(MSG_INFO, "   Attribute %d (%s) length=%d",
288 		   hdr->type, attr ? attr->name : "?Unknown?", hdr->length);
289 
290 	if (attr == NULL || hdr->length < sizeof(struct radius_attr_hdr))
291 		return;
292 
293 	len = hdr->length - sizeof(struct radius_attr_hdr);
294 	pos = (unsigned char *) (hdr + 1);
295 
296 	switch (attr->data_type) {
297 	case RADIUS_ATTR_TEXT:
298 		printf_encode(buf, sizeof(buf), pos, len);
299 		wpa_printf(MSG_INFO, "      Value: '%s'", buf);
300 		break;
301 
302 	case RADIUS_ATTR_IP:
303 		if (len == 4) {
304 			struct in_addr addr;
305 			os_memcpy(&addr, pos, 4);
306 			wpa_printf(MSG_INFO, "      Value: %s",
307 				   inet_ntoa(addr));
308 		} else {
309 			wpa_printf(MSG_INFO, "      Invalid IP address length %d",
310 				   len);
311 		}
312 		break;
313 
314 #ifdef CONFIG_IPV6
315 	case RADIUS_ATTR_IPV6:
316 		if (len == 16) {
317 			const char *atxt;
318 			struct in6_addr *addr = (struct in6_addr *) pos;
319 			atxt = inet_ntop(AF_INET6, addr, buf, sizeof(buf));
320 			wpa_printf(MSG_INFO, "      Value: %s",
321 				   atxt ? atxt : "?");
322 		} else {
323 			wpa_printf(MSG_INFO, "      Invalid IPv6 address length %d",
324 				   len);
325 		}
326 		break;
327 #endif /* CONFIG_IPV6 */
328 
329 	case RADIUS_ATTR_HEXDUMP:
330 	case RADIUS_ATTR_UNDIST:
331 		wpa_snprintf_hex(buf, sizeof(buf), pos, len);
332 		wpa_printf(MSG_INFO, "      Value: %s", buf);
333 		break;
334 
335 	case RADIUS_ATTR_INT32:
336 		if (len == 4)
337 			wpa_printf(MSG_INFO, "      Value: %u",
338 				   WPA_GET_BE32(pos));
339 		else
340 			wpa_printf(MSG_INFO, "      Invalid INT32 length %d",
341 				   len);
342 		break;
343 
344 	default:
345 		break;
346 	}
347 }
348 
349 
radius_msg_dump(struct radius_msg * msg)350 void radius_msg_dump(struct radius_msg *msg)
351 {
352 	size_t i;
353 
354 	wpa_printf(MSG_INFO, "RADIUS message: code=%d (%s) identifier=%d length=%d",
355 		   msg->hdr->code, radius_code_string(msg->hdr->code),
356 		   msg->hdr->identifier, be_to_host16(msg->hdr->length));
357 
358 	for (i = 0; i < msg->attr_used; i++) {
359 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
360 		radius_msg_dump_attr(attr);
361 	}
362 }
363 
364 
radius_msg_finish(struct radius_msg * msg,const u8 * secret,size_t secret_len)365 int radius_msg_finish(struct radius_msg *msg, const u8 *secret,
366 		      size_t secret_len)
367 {
368 	if (secret) {
369 		u8 auth[MD5_MAC_LEN];
370 		struct radius_attr_hdr *attr;
371 
372 		os_memset(auth, 0, MD5_MAC_LEN);
373 		attr = radius_msg_add_attr(msg,
374 					   RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
375 					   auth, MD5_MAC_LEN);
376 		if (attr == NULL) {
377 			wpa_printf(MSG_WARNING, "RADIUS: Could not add "
378 				   "Message-Authenticator");
379 			return -1;
380 		}
381 		msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
382 		hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
383 			 wpabuf_len(msg->buf), (u8 *) (attr + 1));
384 	} else
385 		msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
386 
387 	if (wpabuf_len(msg->buf) > 0xffff) {
388 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
389 			   (unsigned long) wpabuf_len(msg->buf));
390 		return -1;
391 	}
392 	return 0;
393 }
394 
395 
radius_msg_finish_srv(struct radius_msg * msg,const u8 * secret,size_t secret_len,const u8 * req_authenticator)396 int radius_msg_finish_srv(struct radius_msg *msg, const u8 *secret,
397 			  size_t secret_len, const u8 *req_authenticator)
398 {
399 	u8 auth[MD5_MAC_LEN];
400 	struct radius_attr_hdr *attr;
401 	const u8 *addr[4];
402 	size_t len[4];
403 
404 	os_memset(auth, 0, MD5_MAC_LEN);
405 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
406 				   auth, MD5_MAC_LEN);
407 	if (attr == NULL) {
408 		wpa_printf(MSG_ERROR, "WARNING: Could not add Message-Authenticator");
409 		return -1;
410 	}
411 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
412 	os_memcpy(msg->hdr->authenticator, req_authenticator,
413 		  sizeof(msg->hdr->authenticator));
414 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
415 		 wpabuf_len(msg->buf), (u8 *) (attr + 1));
416 
417 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
418 	addr[0] = (u8 *) msg->hdr;
419 	len[0] = 1 + 1 + 2;
420 	addr[1] = req_authenticator;
421 	len[1] = MD5_MAC_LEN;
422 	addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr);
423 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
424 	addr[3] = secret;
425 	len[3] = secret_len;
426 	md5_vector(4, addr, len, msg->hdr->authenticator);
427 
428 	if (wpabuf_len(msg->buf) > 0xffff) {
429 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
430 			   (unsigned long) wpabuf_len(msg->buf));
431 		return -1;
432 	}
433 	return 0;
434 }
435 
436 
radius_msg_finish_das_resp(struct radius_msg * msg,const u8 * secret,size_t secret_len,const struct radius_hdr * req_hdr)437 int radius_msg_finish_das_resp(struct radius_msg *msg, const u8 *secret,
438 			       size_t secret_len,
439 			       const struct radius_hdr *req_hdr)
440 {
441 	const u8 *addr[2];
442 	size_t len[2];
443 	u8 auth[MD5_MAC_LEN];
444 	struct radius_attr_hdr *attr;
445 
446 	os_memset(auth, 0, MD5_MAC_LEN);
447 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_MESSAGE_AUTHENTICATOR,
448 				   auth, MD5_MAC_LEN);
449 	if (attr == NULL) {
450 		wpa_printf(MSG_WARNING, "Could not add Message-Authenticator");
451 		return -1;
452 	}
453 
454 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
455 	os_memcpy(msg->hdr->authenticator, req_hdr->authenticator, 16);
456 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
457 		 wpabuf_len(msg->buf), (u8 *) (attr + 1));
458 
459 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
460 	addr[0] = wpabuf_head_u8(msg->buf);
461 	len[0] = wpabuf_len(msg->buf);
462 	addr[1] = secret;
463 	len[1] = secret_len;
464 	if (md5_vector(2, addr, len, msg->hdr->authenticator) < 0)
465 		return -1;
466 
467 	if (wpabuf_len(msg->buf) > 0xffff) {
468 		wpa_printf(MSG_WARNING, "RADIUS: Too long message (%lu)",
469 			   (unsigned long) wpabuf_len(msg->buf));
470 		return -1;
471 	}
472 	return 0;
473 }
474 
475 
radius_msg_finish_acct(struct radius_msg * msg,const u8 * secret,size_t secret_len)476 void radius_msg_finish_acct(struct radius_msg *msg, const u8 *secret,
477 			    size_t secret_len)
478 {
479 	const u8 *addr[2];
480 	size_t len[2];
481 
482 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
483 	os_memset(msg->hdr->authenticator, 0, MD5_MAC_LEN);
484 	addr[0] = wpabuf_head(msg->buf);
485 	len[0] = wpabuf_len(msg->buf);
486 	addr[1] = secret;
487 	len[1] = secret_len;
488 	md5_vector(2, addr, len, msg->hdr->authenticator);
489 
490 	if (wpabuf_len(msg->buf) > 0xffff) {
491 		wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)",
492 			   (unsigned long) wpabuf_len(msg->buf));
493 	}
494 }
495 
496 
radius_msg_finish_acct_resp(struct radius_msg * msg,const u8 * secret,size_t secret_len,const u8 * req_authenticator)497 void radius_msg_finish_acct_resp(struct radius_msg *msg, const u8 *secret,
498 				 size_t secret_len, const u8 *req_authenticator)
499 {
500 	const u8 *addr[2];
501 	size_t len[2];
502 
503 	msg->hdr->length = host_to_be16(wpabuf_len(msg->buf));
504 	os_memcpy(msg->hdr->authenticator, req_authenticator, MD5_MAC_LEN);
505 	addr[0] = wpabuf_head(msg->buf);
506 	len[0] = wpabuf_len(msg->buf);
507 	addr[1] = secret;
508 	len[1] = secret_len;
509 	md5_vector(2, addr, len, msg->hdr->authenticator);
510 
511 	if (wpabuf_len(msg->buf) > 0xffff) {
512 		wpa_printf(MSG_WARNING, "RADIUS: Too long messages (%lu)",
513 			   (unsigned long) wpabuf_len(msg->buf));
514 	}
515 }
516 
517 
radius_msg_verify_acct_req(struct radius_msg * msg,const u8 * secret,size_t secret_len)518 int radius_msg_verify_acct_req(struct radius_msg *msg, const u8 *secret,
519 			       size_t secret_len)
520 {
521 	const u8 *addr[4];
522 	size_t len[4];
523 	u8 zero[MD5_MAC_LEN];
524 	u8 hash[MD5_MAC_LEN];
525 
526 	os_memset(zero, 0, sizeof(zero));
527 	addr[0] = (u8 *) msg->hdr;
528 	len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN;
529 	addr[1] = zero;
530 	len[1] = MD5_MAC_LEN;
531 	addr[2] = (u8 *) (msg->hdr + 1);
532 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
533 	addr[3] = secret;
534 	len[3] = secret_len;
535 	md5_vector(4, addr, len, hash);
536 	return os_memcmp_const(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0;
537 }
538 
539 
radius_msg_verify_das_req(struct radius_msg * msg,const u8 * secret,size_t secret_len,int require_message_authenticator)540 int radius_msg_verify_das_req(struct radius_msg *msg, const u8 *secret,
541 			      size_t secret_len,
542 			      int require_message_authenticator)
543 {
544 	const u8 *addr[4];
545 	size_t len[4];
546 	u8 zero[MD5_MAC_LEN];
547 	u8 hash[MD5_MAC_LEN];
548 	u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
549 	u8 orig_authenticator[16];
550 
551 	struct radius_attr_hdr *attr = NULL, *tmp;
552 	size_t i;
553 
554 	os_memset(zero, 0, sizeof(zero));
555 	addr[0] = (u8 *) msg->hdr;
556 	len[0] = sizeof(struct radius_hdr) - MD5_MAC_LEN;
557 	addr[1] = zero;
558 	len[1] = MD5_MAC_LEN;
559 	addr[2] = (u8 *) (msg->hdr + 1);
560 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
561 	addr[3] = secret;
562 	len[3] = secret_len;
563 	md5_vector(4, addr, len, hash);
564 	if (os_memcmp_const(msg->hdr->authenticator, hash, MD5_MAC_LEN) != 0)
565 		return 1;
566 
567 	for (i = 0; i < msg->attr_used; i++) {
568 		tmp = radius_get_attr_hdr(msg, i);
569 		if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
570 			if (attr != NULL) {
571 				wpa_printf(MSG_WARNING, "Multiple "
572 					   "Message-Authenticator attributes "
573 					   "in RADIUS message");
574 				return 1;
575 			}
576 			attr = tmp;
577 		}
578 	}
579 
580 	if (attr == NULL) {
581 		if (require_message_authenticator) {
582 			wpa_printf(MSG_WARNING,
583 				   "Missing Message-Authenticator attribute in RADIUS message");
584 			return 1;
585 		}
586 		return 0;
587 	}
588 
589 	os_memcpy(orig, attr + 1, MD5_MAC_LEN);
590 	os_memset(attr + 1, 0, MD5_MAC_LEN);
591 	os_memcpy(orig_authenticator, msg->hdr->authenticator,
592 		  sizeof(orig_authenticator));
593 	os_memset(msg->hdr->authenticator, 0,
594 		  sizeof(msg->hdr->authenticator));
595 	hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
596 		 wpabuf_len(msg->buf), auth);
597 	os_memcpy(attr + 1, orig, MD5_MAC_LEN);
598 	os_memcpy(msg->hdr->authenticator, orig_authenticator,
599 		  sizeof(orig_authenticator));
600 
601 	return os_memcmp_const(orig, auth, MD5_MAC_LEN) != 0;
602 }
603 
604 
radius_msg_add_attr_to_array(struct radius_msg * msg,struct radius_attr_hdr * attr)605 static int radius_msg_add_attr_to_array(struct radius_msg *msg,
606 					struct radius_attr_hdr *attr)
607 {
608 	if (msg->attr_used >= msg->attr_size) {
609 		size_t *nattr_pos;
610 		int nlen = msg->attr_size * 2;
611 
612 		nattr_pos = os_realloc_array(msg->attr_pos, nlen,
613 					     sizeof(*msg->attr_pos));
614 		if (nattr_pos == NULL)
615 			return -1;
616 
617 		msg->attr_pos = nattr_pos;
618 		msg->attr_size = nlen;
619 	}
620 
621 	msg->attr_pos[msg->attr_used++] =
622 		(unsigned char *) attr - wpabuf_head_u8(msg->buf);
623 
624 	return 0;
625 }
626 
627 
radius_msg_add_attr(struct radius_msg * msg,u8 type,const u8 * data,size_t data_len)628 struct radius_attr_hdr *radius_msg_add_attr(struct radius_msg *msg, u8 type,
629 					    const u8 *data, size_t data_len)
630 {
631 	size_t buf_needed;
632 	struct radius_attr_hdr *attr;
633 
634 	if (TEST_FAIL())
635 		return NULL;
636 
637 	if (data_len > RADIUS_MAX_ATTR_LEN) {
638 		wpa_printf(MSG_ERROR, "radius_msg_add_attr: too long attribute (%lu bytes)",
639 		       (unsigned long) data_len);
640 		return NULL;
641 	}
642 
643 	buf_needed = sizeof(*attr) + data_len;
644 
645 	if (wpabuf_tailroom(msg->buf) < buf_needed) {
646 		/* allocate more space for message buffer */
647 		if (wpabuf_resize(&msg->buf, buf_needed) < 0)
648 			return NULL;
649 		msg->hdr = wpabuf_mhead(msg->buf);
650 	}
651 
652 	attr = wpabuf_put(msg->buf, sizeof(struct radius_attr_hdr));
653 	attr->type = type;
654 	attr->length = sizeof(*attr) + data_len;
655 	wpabuf_put_data(msg->buf, data, data_len);
656 
657 	if (radius_msg_add_attr_to_array(msg, attr))
658 		return NULL;
659 
660 	return attr;
661 }
662 
663 
664 /**
665  * radius_msg_parse - Parse a RADIUS message
666  * @data: RADIUS message to be parsed
667  * @len: Length of data buffer in octets
668  * Returns: Parsed RADIUS message or %NULL on failure
669  *
670  * This parses a RADIUS message and makes a copy of its data. The caller is
671  * responsible for freeing the returned data with radius_msg_free().
672  */
radius_msg_parse(const u8 * data,size_t len)673 struct radius_msg * radius_msg_parse(const u8 *data, size_t len)
674 {
675 	struct radius_msg *msg;
676 	struct radius_hdr *hdr;
677 	struct radius_attr_hdr *attr;
678 	size_t msg_len;
679 	unsigned char *pos, *end;
680 
681 	if (data == NULL || len < sizeof(*hdr))
682 		return NULL;
683 
684 	hdr = (struct radius_hdr *) data;
685 
686 	msg_len = be_to_host16(hdr->length);
687 	if (msg_len < sizeof(*hdr) || msg_len > len) {
688 		wpa_printf(MSG_INFO, "RADIUS: Invalid message length");
689 		return NULL;
690 	}
691 
692 	if (msg_len < len) {
693 		wpa_printf(MSG_DEBUG, "RADIUS: Ignored %lu extra bytes after "
694 			   "RADIUS message", (unsigned long) len - msg_len);
695 	}
696 
697 	msg = os_zalloc(sizeof(*msg));
698 	if (msg == NULL)
699 		return NULL;
700 
701 	msg->buf = wpabuf_alloc_copy(data, msg_len);
702 	if (msg->buf == NULL || radius_msg_initialize(msg)) {
703 		radius_msg_free(msg);
704 		return NULL;
705 	}
706 	msg->hdr = wpabuf_mhead(msg->buf);
707 
708 	/* parse attributes */
709 	pos = wpabuf_mhead_u8(msg->buf) + sizeof(struct radius_hdr);
710 	end = wpabuf_mhead_u8(msg->buf) + wpabuf_len(msg->buf);
711 	while (pos < end) {
712 		if ((size_t) (end - pos) < sizeof(*attr))
713 			goto fail;
714 
715 		attr = (struct radius_attr_hdr *) pos;
716 
717 		if (attr->length > end - pos || attr->length < sizeof(*attr))
718 			goto fail;
719 
720 		/* TODO: check that attr->length is suitable for attr->type */
721 
722 		if (radius_msg_add_attr_to_array(msg, attr))
723 			goto fail;
724 
725 		pos += attr->length;
726 	}
727 
728 	return msg;
729 
730  fail:
731 	radius_msg_free(msg);
732 	return NULL;
733 }
734 
735 
radius_msg_add_eap(struct radius_msg * msg,const u8 * data,size_t data_len)736 int radius_msg_add_eap(struct radius_msg *msg, const u8 *data, size_t data_len)
737 {
738 	const u8 *pos = data;
739 	size_t left = data_len;
740 
741 	while (left > 0) {
742 		int len;
743 		if (left > RADIUS_MAX_ATTR_LEN)
744 			len = RADIUS_MAX_ATTR_LEN;
745 		else
746 			len = left;
747 
748 		if (!radius_msg_add_attr(msg, RADIUS_ATTR_EAP_MESSAGE,
749 					 pos, len))
750 			return 0;
751 
752 		pos += len;
753 		left -= len;
754 	}
755 
756 	return 1;
757 }
758 
759 
radius_msg_get_eap(struct radius_msg * msg)760 struct wpabuf * radius_msg_get_eap(struct radius_msg *msg)
761 {
762 	struct wpabuf *eap;
763 	size_t len, i;
764 	struct radius_attr_hdr *attr;
765 
766 	if (msg == NULL)
767 		return NULL;
768 
769 	len = 0;
770 	for (i = 0; i < msg->attr_used; i++) {
771 		attr = radius_get_attr_hdr(msg, i);
772 		if (attr->type == RADIUS_ATTR_EAP_MESSAGE &&
773 		    attr->length > sizeof(struct radius_attr_hdr))
774 			len += attr->length - sizeof(struct radius_attr_hdr);
775 	}
776 
777 	if (len == 0)
778 		return NULL;
779 
780 	eap = wpabuf_alloc(len);
781 	if (eap == NULL)
782 		return NULL;
783 
784 	for (i = 0; i < msg->attr_used; i++) {
785 		attr = radius_get_attr_hdr(msg, i);
786 		if (attr->type == RADIUS_ATTR_EAP_MESSAGE &&
787 		    attr->length > sizeof(struct radius_attr_hdr)) {
788 			int flen = attr->length - sizeof(*attr);
789 			wpabuf_put_data(eap, attr + 1, flen);
790 		}
791 	}
792 
793 	return eap;
794 }
795 
796 
radius_msg_verify_msg_auth(struct radius_msg * msg,const u8 * secret,size_t secret_len,const u8 * req_auth)797 int radius_msg_verify_msg_auth(struct radius_msg *msg, const u8 *secret,
798 			       size_t secret_len, const u8 *req_auth)
799 {
800 	u8 auth[MD5_MAC_LEN], orig[MD5_MAC_LEN];
801 	u8 orig_authenticator[16];
802 	struct radius_attr_hdr *attr = NULL, *tmp;
803 	size_t i;
804 
805 	for (i = 0; i < msg->attr_used; i++) {
806 		tmp = radius_get_attr_hdr(msg, i);
807 		if (tmp->type == RADIUS_ATTR_MESSAGE_AUTHENTICATOR) {
808 			if (attr != NULL) {
809 				wpa_printf(MSG_INFO, "Multiple Message-Authenticator attributes in RADIUS message");
810 				return 1;
811 			}
812 			attr = tmp;
813 		}
814 	}
815 
816 	if (attr == NULL) {
817 		wpa_printf(MSG_INFO, "No Message-Authenticator attribute found");
818 		return 1;
819 	}
820 
821 	os_memcpy(orig, attr + 1, MD5_MAC_LEN);
822 	os_memset(attr + 1, 0, MD5_MAC_LEN);
823 	if (req_auth) {
824 		os_memcpy(orig_authenticator, msg->hdr->authenticator,
825 			  sizeof(orig_authenticator));
826 		os_memcpy(msg->hdr->authenticator, req_auth,
827 			  sizeof(msg->hdr->authenticator));
828 	}
829 	if (hmac_md5(secret, secret_len, wpabuf_head(msg->buf),
830 		     wpabuf_len(msg->buf), auth) < 0)
831 		return 1;
832 	os_memcpy(attr + 1, orig, MD5_MAC_LEN);
833 	if (req_auth) {
834 		os_memcpy(msg->hdr->authenticator, orig_authenticator,
835 			  sizeof(orig_authenticator));
836 	}
837 
838 	if (os_memcmp_const(orig, auth, MD5_MAC_LEN) != 0) {
839 		wpa_printf(MSG_INFO, "Invalid Message-Authenticator!");
840 		return 1;
841 	}
842 
843 	return 0;
844 }
845 
846 
radius_msg_verify(struct radius_msg * msg,const u8 * secret,size_t secret_len,struct radius_msg * sent_msg,int auth)847 int radius_msg_verify(struct radius_msg *msg, const u8 *secret,
848 		      size_t secret_len, struct radius_msg *sent_msg, int auth)
849 {
850 	const u8 *addr[4];
851 	size_t len[4];
852 	u8 hash[MD5_MAC_LEN];
853 
854 	if (sent_msg == NULL) {
855 		wpa_printf(MSG_INFO, "No matching Access-Request message found");
856 		return 1;
857 	}
858 
859 	if (auth &&
860 	    radius_msg_verify_msg_auth(msg, secret, secret_len,
861 				       sent_msg->hdr->authenticator)) {
862 		return 1;
863 	}
864 
865 	/* ResponseAuth = MD5(Code+ID+Length+RequestAuth+Attributes+Secret) */
866 	addr[0] = (u8 *) msg->hdr;
867 	len[0] = 1 + 1 + 2;
868 	addr[1] = sent_msg->hdr->authenticator;
869 	len[1] = MD5_MAC_LEN;
870 	addr[2] = wpabuf_head_u8(msg->buf) + sizeof(struct radius_hdr);
871 	len[2] = wpabuf_len(msg->buf) - sizeof(struct radius_hdr);
872 	addr[3] = secret;
873 	len[3] = secret_len;
874 	if (md5_vector(4, addr, len, hash) < 0 ||
875 	    os_memcmp_const(hash, msg->hdr->authenticator, MD5_MAC_LEN) != 0) {
876 		wpa_printf(MSG_INFO, "Response Authenticator invalid!");
877 		return 1;
878 	}
879 
880 	return 0;
881 }
882 
883 
radius_msg_copy_attr(struct radius_msg * dst,struct radius_msg * src,u8 type)884 int radius_msg_copy_attr(struct radius_msg *dst, struct radius_msg *src,
885 			 u8 type)
886 {
887 	struct radius_attr_hdr *attr;
888 	size_t i;
889 	int count = 0;
890 
891 	for (i = 0; i < src->attr_used; i++) {
892 		attr = radius_get_attr_hdr(src, i);
893 		if (attr->type == type && attr->length >= sizeof(*attr)) {
894 			if (!radius_msg_add_attr(dst, type, (u8 *) (attr + 1),
895 						 attr->length - sizeof(*attr)))
896 				return -1;
897 			count++;
898 		}
899 	}
900 
901 	return count;
902 }
903 
904 
905 /* Create Request Authenticator. The value should be unique over the lifetime
906  * of the shared secret between authenticator and authentication server.
907  */
radius_msg_make_authenticator(struct radius_msg * msg)908 int radius_msg_make_authenticator(struct radius_msg *msg)
909 {
910 	return os_get_random((u8 *) &msg->hdr->authenticator,
911 			     sizeof(msg->hdr->authenticator));
912 }
913 
914 
915 /* Get Vendor-specific RADIUS Attribute from a parsed RADIUS message.
916  * Returns the Attribute payload and sets alen to indicate the length of the
917  * payload if a vendor attribute with subtype is found, otherwise returns NULL.
918  * The returned payload is allocated with os_malloc() and caller must free it
919  * by calling os_free().
920  */
radius_msg_get_vendor_attr(struct radius_msg * msg,u32 vendor,u8 subtype,size_t * alen)921 static u8 *radius_msg_get_vendor_attr(struct radius_msg *msg, u32 vendor,
922 				      u8 subtype, size_t *alen)
923 {
924 	u8 *data, *pos;
925 	size_t i, len;
926 
927 	if (msg == NULL)
928 		return NULL;
929 
930 	for (i = 0; i < msg->attr_used; i++) {
931 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
932 		size_t left;
933 		u32 vendor_id;
934 		struct radius_attr_vendor *vhdr;
935 
936 		if (attr->type != RADIUS_ATTR_VENDOR_SPECIFIC ||
937 		    attr->length < sizeof(*attr))
938 			continue;
939 
940 		left = attr->length - sizeof(*attr);
941 		if (left < 4)
942 			continue;
943 
944 		pos = (u8 *) (attr + 1);
945 
946 		os_memcpy(&vendor_id, pos, 4);
947 		pos += 4;
948 		left -= 4;
949 
950 		if (ntohl(vendor_id) != vendor)
951 			continue;
952 
953 		while (left >= sizeof(*vhdr)) {
954 			vhdr = (struct radius_attr_vendor *) pos;
955 			if (vhdr->vendor_length > left ||
956 			    vhdr->vendor_length < sizeof(*vhdr)) {
957 				break;
958 			}
959 			if (vhdr->vendor_type != subtype) {
960 				pos += vhdr->vendor_length;
961 				left -= vhdr->vendor_length;
962 				continue;
963 			}
964 
965 			len = vhdr->vendor_length - sizeof(*vhdr);
966 			data = os_memdup(pos + sizeof(*vhdr), len);
967 			if (data == NULL)
968 				return NULL;
969 			if (alen)
970 				*alen = len;
971 			return data;
972 		}
973 	}
974 
975 	return NULL;
976 }
977 
978 
decrypt_ms_key(const u8 * key,size_t len,const u8 * req_authenticator,const u8 * secret,size_t secret_len,size_t * reslen)979 static u8 * decrypt_ms_key(const u8 *key, size_t len,
980 			   const u8 *req_authenticator,
981 			   const u8 *secret, size_t secret_len, size_t *reslen)
982 {
983 	u8 *plain, *ppos, *res;
984 	const u8 *pos;
985 	size_t left, plen;
986 	u8 hash[MD5_MAC_LEN];
987 	int i, first = 1;
988 	const u8 *addr[3];
989 	size_t elen[3];
990 
991 	/* key: 16-bit salt followed by encrypted key info */
992 
993 	if (len < 2 + 16) {
994 		wpa_printf(MSG_DEBUG, "RADIUS: %s: Len is too small: %d",
995 			   __func__, (int) len);
996 		return NULL;
997 	}
998 
999 	pos = key + 2;
1000 	left = len - 2;
1001 	if (left % 16) {
1002 		wpa_printf(MSG_INFO, "RADIUS: Invalid ms key len %lu",
1003 			   (unsigned long) left);
1004 		return NULL;
1005 	}
1006 
1007 	plen = left;
1008 	ppos = plain = os_malloc(plen);
1009 	if (plain == NULL)
1010 		return NULL;
1011 	plain[0] = 0;
1012 
1013 	while (left > 0) {
1014 		/* b(1) = MD5(Secret + Request-Authenticator + Salt)
1015 		 * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
1016 
1017 		addr[0] = secret;
1018 		elen[0] = secret_len;
1019 		if (first) {
1020 			addr[1] = req_authenticator;
1021 			elen[1] = MD5_MAC_LEN;
1022 			addr[2] = key;
1023 			elen[2] = 2; /* Salt */
1024 		} else {
1025 			addr[1] = pos - MD5_MAC_LEN;
1026 			elen[1] = MD5_MAC_LEN;
1027 		}
1028 		if (md5_vector(first ? 3 : 2, addr, elen, hash) < 0) {
1029 			os_free(plain);
1030 			return NULL;
1031 		}
1032 		first = 0;
1033 
1034 		for (i = 0; i < MD5_MAC_LEN; i++)
1035 			*ppos++ = *pos++ ^ hash[i];
1036 		left -= MD5_MAC_LEN;
1037 	}
1038 
1039 	if (plain[0] == 0 || plain[0] > plen - 1) {
1040 		wpa_printf(MSG_INFO, "RADIUS: Failed to decrypt MPPE key");
1041 		os_free(plain);
1042 		return NULL;
1043 	}
1044 
1045 	res = os_memdup(plain + 1, plain[0]);
1046 	if (res == NULL) {
1047 		os_free(plain);
1048 		return NULL;
1049 	}
1050 	if (reslen)
1051 		*reslen = plain[0];
1052 	os_free(plain);
1053 	return res;
1054 }
1055 
1056 
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)1057 static void encrypt_ms_key(const u8 *key, size_t key_len, u16 salt,
1058 			   const u8 *req_authenticator,
1059 			   const u8 *secret, size_t secret_len,
1060 			   u8 *ebuf, size_t *elen)
1061 {
1062 	int i, len, first = 1;
1063 	u8 hash[MD5_MAC_LEN], saltbuf[2], *pos;
1064 	const u8 *addr[3];
1065 	size_t _len[3];
1066 
1067 	WPA_PUT_BE16(saltbuf, salt);
1068 
1069 	len = 1 + key_len;
1070 	if (len & 0x0f) {
1071 		len = (len & 0xf0) + 16;
1072 	}
1073 	os_memset(ebuf, 0, len);
1074 	ebuf[0] = key_len;
1075 	os_memcpy(ebuf + 1, key, key_len);
1076 
1077 	*elen = len;
1078 
1079 	pos = ebuf;
1080 	while (len > 0) {
1081 		/* b(1) = MD5(Secret + Request-Authenticator + Salt)
1082 		 * b(i) = MD5(Secret + c(i - 1)) for i > 1 */
1083 		addr[0] = secret;
1084 		_len[0] = secret_len;
1085 		if (first) {
1086 			addr[1] = req_authenticator;
1087 			_len[1] = MD5_MAC_LEN;
1088 			addr[2] = saltbuf;
1089 			_len[2] = sizeof(saltbuf);
1090 		} else {
1091 			addr[1] = pos - MD5_MAC_LEN;
1092 			_len[1] = MD5_MAC_LEN;
1093 		}
1094 		md5_vector(first ? 3 : 2, addr, _len, hash);
1095 		first = 0;
1096 
1097 		for (i = 0; i < MD5_MAC_LEN; i++)
1098 			*pos++ ^= hash[i];
1099 
1100 		len -= MD5_MAC_LEN;
1101 	}
1102 }
1103 
1104 
1105 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)1106 radius_msg_get_ms_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
1107 		       const u8 *secret, size_t secret_len)
1108 {
1109 	u8 *key;
1110 	size_t keylen;
1111 	struct radius_ms_mppe_keys *keys;
1112 
1113 	if (msg == NULL || sent_msg == NULL)
1114 		return NULL;
1115 
1116 	keys = os_zalloc(sizeof(*keys));
1117 	if (keys == NULL)
1118 		return NULL;
1119 
1120 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
1121 					 RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY,
1122 					 &keylen);
1123 	if (key) {
1124 		keys->send = decrypt_ms_key(key, keylen,
1125 					    sent_msg->hdr->authenticator,
1126 					    secret, secret_len,
1127 					    &keys->send_len);
1128 		if (!keys->send) {
1129 			wpa_printf(MSG_DEBUG,
1130 				   "RADIUS: Failed to decrypt send key");
1131 		}
1132 		os_free(key);
1133 	}
1134 
1135 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_MICROSOFT,
1136 					 RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY,
1137 					 &keylen);
1138 	if (key) {
1139 		keys->recv = decrypt_ms_key(key, keylen,
1140 					    sent_msg->hdr->authenticator,
1141 					    secret, secret_len,
1142 					    &keys->recv_len);
1143 		if (!keys->recv) {
1144 			wpa_printf(MSG_DEBUG,
1145 				   "RADIUS: Failed to decrypt recv key");
1146 		}
1147 		os_free(key);
1148 	}
1149 
1150 	return keys;
1151 }
1152 
1153 
1154 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)1155 radius_msg_get_cisco_keys(struct radius_msg *msg, struct radius_msg *sent_msg,
1156 			  const u8 *secret, size_t secret_len)
1157 {
1158 	u8 *key;
1159 	size_t keylen;
1160 	struct radius_ms_mppe_keys *keys;
1161 
1162 	if (msg == NULL || sent_msg == NULL)
1163 		return NULL;
1164 
1165 	keys = os_zalloc(sizeof(*keys));
1166 	if (keys == NULL)
1167 		return NULL;
1168 
1169 	key = radius_msg_get_vendor_attr(msg, RADIUS_VENDOR_ID_CISCO,
1170 					 RADIUS_CISCO_AV_PAIR, &keylen);
1171 	if (key && keylen == 51 &&
1172 	    os_memcmp(key, "leap:session-key=", 17) == 0) {
1173 		keys->recv = decrypt_ms_key(key + 17, keylen - 17,
1174 					    sent_msg->hdr->authenticator,
1175 					    secret, secret_len,
1176 					    &keys->recv_len);
1177 	}
1178 	os_free(key);
1179 
1180 	return keys;
1181 }
1182 
1183 
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)1184 int radius_msg_add_mppe_keys(struct radius_msg *msg,
1185 			     const u8 *req_authenticator,
1186 			     const u8 *secret, size_t secret_len,
1187 			     const u8 *send_key, size_t send_key_len,
1188 			     const u8 *recv_key, size_t recv_key_len)
1189 {
1190 	struct radius_attr_hdr *attr;
1191 	u32 vendor_id = htonl(RADIUS_VENDOR_ID_MICROSOFT);
1192 	u8 *buf;
1193 	struct radius_attr_vendor *vhdr;
1194 	u8 *pos;
1195 	size_t elen;
1196 	int hlen;
1197 	u16 salt;
1198 
1199 	hlen = sizeof(vendor_id) + sizeof(*vhdr) + 2;
1200 
1201 	/* MS-MPPE-Send-Key */
1202 	buf = os_malloc(hlen + send_key_len + 16);
1203 	if (buf == NULL) {
1204 		return 0;
1205 	}
1206 	pos = buf;
1207 	os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1208 	pos += sizeof(vendor_id);
1209 	vhdr = (struct radius_attr_vendor *) pos;
1210 	vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_SEND_KEY;
1211 	pos = (u8 *) (vhdr + 1);
1212 	if (os_get_random((u8 *) &salt, sizeof(salt)) < 0) {
1213 		os_free(buf);
1214 		return 0;
1215 	}
1216 	salt |= 0x8000;
1217 	WPA_PUT_BE16(pos, salt);
1218 	pos += 2;
1219 	encrypt_ms_key(send_key, send_key_len, salt, req_authenticator, secret,
1220 		       secret_len, pos, &elen);
1221 	vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1222 
1223 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1224 				   buf, hlen + elen);
1225 	os_free(buf);
1226 	if (attr == NULL) {
1227 		return 0;
1228 	}
1229 
1230 	/* MS-MPPE-Recv-Key */
1231 	buf = os_malloc(hlen + recv_key_len + 16);
1232 	if (buf == NULL) {
1233 		return 0;
1234 	}
1235 	pos = buf;
1236 	os_memcpy(pos, &vendor_id, sizeof(vendor_id));
1237 	pos += sizeof(vendor_id);
1238 	vhdr = (struct radius_attr_vendor *) pos;
1239 	vhdr->vendor_type = RADIUS_VENDOR_ATTR_MS_MPPE_RECV_KEY;
1240 	pos = (u8 *) (vhdr + 1);
1241 	salt ^= 1;
1242 	WPA_PUT_BE16(pos, salt);
1243 	pos += 2;
1244 	encrypt_ms_key(recv_key, recv_key_len, salt, req_authenticator, secret,
1245 		       secret_len, pos, &elen);
1246 	vhdr->vendor_length = hlen + elen - sizeof(vendor_id);
1247 
1248 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1249 				   buf, hlen + elen);
1250 	os_free(buf);
1251 	if (attr == NULL) {
1252 		return 0;
1253 	}
1254 
1255 	return 1;
1256 }
1257 
1258 
radius_msg_add_wfa(struct radius_msg * msg,u8 subtype,const u8 * data,size_t len)1259 int radius_msg_add_wfa(struct radius_msg *msg, u8 subtype, const u8 *data,
1260 		       size_t len)
1261 {
1262 	struct radius_attr_hdr *attr;
1263 	u8 *buf, *pos;
1264 	size_t alen;
1265 
1266 	alen = 4 + 2 + len;
1267 	buf = os_malloc(alen);
1268 	if (buf == NULL)
1269 		return 0;
1270 	pos = buf;
1271 	WPA_PUT_BE32(pos, RADIUS_VENDOR_ID_WFA);
1272 	pos += 4;
1273 	*pos++ = subtype;
1274 	*pos++ = 2 + len;
1275 	os_memcpy(pos, data, len);
1276 	attr = radius_msg_add_attr(msg, RADIUS_ATTR_VENDOR_SPECIFIC,
1277 				   buf, alen);
1278 	os_free(buf);
1279 	if (attr == NULL)
1280 		return 0;
1281 
1282 	return 1;
1283 }
1284 
1285 
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)1286 int radius_user_password_hide(struct radius_msg *msg,
1287 			      const u8 *data, size_t data_len,
1288 			      const u8 *secret, size_t secret_len,
1289 			      u8 *buf, size_t buf_len)
1290 {
1291 	size_t padlen, i, pos;
1292 	const u8 *addr[2];
1293 	size_t len[2];
1294 	u8 hash[16];
1295 
1296 	if (data_len + 16 > buf_len)
1297 		return -1;
1298 
1299 	os_memcpy(buf, data, data_len);
1300 
1301 	padlen = data_len % 16;
1302 	if (padlen && data_len < buf_len) {
1303 		padlen = 16 - padlen;
1304 		os_memset(buf + data_len, 0, padlen);
1305 		buf_len = data_len + padlen;
1306 	} else {
1307 		buf_len = data_len;
1308 	}
1309 
1310 	addr[0] = secret;
1311 	len[0] = secret_len;
1312 	addr[1] = msg->hdr->authenticator;
1313 	len[1] = 16;
1314 	md5_vector(2, addr, len, hash);
1315 
1316 	for (i = 0; i < 16; i++)
1317 		buf[i] ^= hash[i];
1318 	pos = 16;
1319 
1320 	while (pos < buf_len) {
1321 		addr[0] = secret;
1322 		len[0] = secret_len;
1323 		addr[1] = &buf[pos - 16];
1324 		len[1] = 16;
1325 		md5_vector(2, addr, len, hash);
1326 
1327 		for (i = 0; i < 16; i++)
1328 			buf[pos + i] ^= hash[i];
1329 
1330 		pos += 16;
1331 	}
1332 
1333 	return buf_len;
1334 }
1335 
1336 
1337 /* Add User-Password attribute to a RADIUS message and encrypt it as specified
1338  * in RFC 2865, Chap. 5.2 */
1339 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)1340 radius_msg_add_attr_user_password(struct radius_msg *msg,
1341 				  const u8 *data, size_t data_len,
1342 				  const u8 *secret, size_t secret_len)
1343 {
1344 	u8 buf[128];
1345 	int res;
1346 
1347 	res = radius_user_password_hide(msg, data, data_len,
1348 					secret, secret_len, buf, sizeof(buf));
1349 	if (res < 0)
1350 		return NULL;
1351 
1352 	return radius_msg_add_attr(msg, RADIUS_ATTR_USER_PASSWORD,
1353 				   buf, res);
1354 }
1355 
1356 
radius_msg_get_attr(struct radius_msg * msg,u8 type,u8 * buf,size_t len)1357 int radius_msg_get_attr(struct radius_msg *msg, u8 type, u8 *buf, size_t len)
1358 {
1359 	struct radius_attr_hdr *attr = NULL, *tmp;
1360 	size_t i, dlen;
1361 
1362 	for (i = 0; i < msg->attr_used; i++) {
1363 		tmp = radius_get_attr_hdr(msg, i);
1364 		if (tmp->type == type) {
1365 			attr = tmp;
1366 			break;
1367 		}
1368 	}
1369 
1370 	if (!attr || attr->length < sizeof(*attr))
1371 		return -1;
1372 
1373 	dlen = attr->length - sizeof(*attr);
1374 	if (buf)
1375 		os_memcpy(buf, (attr + 1), dlen > len ? len : dlen);
1376 	return dlen;
1377 }
1378 
1379 
radius_msg_get_attr_ptr(struct radius_msg * msg,u8 type,u8 ** buf,size_t * len,const u8 * start)1380 int radius_msg_get_attr_ptr(struct radius_msg *msg, u8 type, u8 **buf,
1381 			    size_t *len, const u8 *start)
1382 {
1383 	size_t i;
1384 	struct radius_attr_hdr *attr = NULL, *tmp;
1385 
1386 	for (i = 0; i < msg->attr_used; i++) {
1387 		tmp = radius_get_attr_hdr(msg, i);
1388 		if (tmp->type == type &&
1389 		    (start == NULL || (u8 *) tmp > start)) {
1390 			attr = tmp;
1391 			break;
1392 		}
1393 	}
1394 
1395 	if (!attr || attr->length < sizeof(*attr))
1396 		return -1;
1397 
1398 	*buf = (u8 *) (attr + 1);
1399 	*len = attr->length - sizeof(*attr);
1400 	return 0;
1401 }
1402 
1403 
radius_msg_count_attr(struct radius_msg * msg,u8 type,int min_len)1404 int radius_msg_count_attr(struct radius_msg *msg, u8 type, int min_len)
1405 {
1406 	size_t i;
1407 	int count;
1408 
1409 	for (count = 0, i = 0; i < msg->attr_used; i++) {
1410 		struct radius_attr_hdr *attr = radius_get_attr_hdr(msg, i);
1411 		if (attr->type == type &&
1412 		    attr->length >= sizeof(struct radius_attr_hdr) + min_len)
1413 			count++;
1414 	}
1415 
1416 	return count;
1417 }
1418 
1419 
1420 struct radius_tunnel_attrs {
1421 	int tag_used;
1422 	int type; /* Tunnel-Type */
1423 	int medium_type; /* Tunnel-Medium-Type */
1424 	int vlanid;
1425 };
1426 
1427 
cmp_int(const void * a,const void * b)1428 static int cmp_int(const void *a, const void *b)
1429 {
1430 	int x, y;
1431 
1432 	x = *((int *) a);
1433 	y = *((int *) b);
1434 	return (x - y);
1435 }
1436 
1437 
1438 /**
1439  * radius_msg_get_vlanid - Parse RADIUS attributes for VLAN tunnel information
1440  * The k tagged vlans found are sorted by vlan_id and stored in the first k
1441  * items of tagged.
1442  *
1443  * @msg: RADIUS message
1444  * @untagged: Pointer to store untagged vid
1445  * @numtagged: Size of tagged
1446  * @tagged: Pointer to store tagged list
1447  *
1448  * Returns: 0 if neither tagged nor untagged configuration is found, 1 otherwise
1449  */
radius_msg_get_vlanid(struct radius_msg * msg,int * untagged,int numtagged,int * tagged)1450 int radius_msg_get_vlanid(struct radius_msg *msg, int *untagged, int numtagged,
1451 			  int *tagged)
1452 {
1453 	struct radius_tunnel_attrs tunnel[RADIUS_TUNNEL_TAGS], *tun;
1454 	size_t i;
1455 	struct radius_attr_hdr *attr = NULL;
1456 	const u8 *data;
1457 	char buf[10];
1458 	size_t dlen;
1459 	int j, taggedidx = 0, vlan_id;
1460 
1461 	os_memset(&tunnel, 0, sizeof(tunnel));
1462 	for (j = 0; j < numtagged; j++)
1463 		tagged[j] = 0;
1464 	*untagged = 0;
1465 
1466 	for (i = 0; i < msg->attr_used; i++) {
1467 		attr = radius_get_attr_hdr(msg, i);
1468 		if (attr->length < sizeof(*attr))
1469 			return -1;
1470 		data = (const u8 *) (attr + 1);
1471 		dlen = attr->length - sizeof(*attr);
1472 		if (attr->length < 3)
1473 			continue;
1474 		if (data[0] >= RADIUS_TUNNEL_TAGS)
1475 			tun = &tunnel[0];
1476 		else
1477 			tun = &tunnel[data[0]];
1478 
1479 		switch (attr->type) {
1480 		case RADIUS_ATTR_TUNNEL_TYPE:
1481 			if (attr->length != 6)
1482 				break;
1483 			tun->tag_used++;
1484 			tun->type = WPA_GET_BE24(data + 1);
1485 			break;
1486 		case RADIUS_ATTR_TUNNEL_MEDIUM_TYPE:
1487 			if (attr->length != 6)
1488 				break;
1489 			tun->tag_used++;
1490 			tun->medium_type = WPA_GET_BE24(data + 1);
1491 			break;
1492 		case RADIUS_ATTR_TUNNEL_PRIVATE_GROUP_ID:
1493 			if (data[0] < RADIUS_TUNNEL_TAGS) {
1494 				data++;
1495 				dlen--;
1496 			}
1497 			if (dlen >= sizeof(buf))
1498 				break;
1499 			os_memcpy(buf, data, dlen);
1500 			buf[dlen] = '\0';
1501 			vlan_id = atoi(buf);
1502 			if (vlan_id <= 0)
1503 				break;
1504 			tun->tag_used++;
1505 			tun->vlanid = vlan_id;
1506 			break;
1507 		case RADIUS_ATTR_EGRESS_VLANID: /* RFC 4675 */
1508 			if (attr->length != 6)
1509 				break;
1510 			vlan_id = WPA_GET_BE24(data + 1);
1511 			if (vlan_id <= 0)
1512 				break;
1513 			if (data[0] == 0x32)
1514 				*untagged = vlan_id;
1515 			else if (data[0] == 0x31 && tagged &&
1516 				 taggedidx < numtagged)
1517 				tagged[taggedidx++] = vlan_id;
1518 			break;
1519 		}
1520 	}
1521 
1522 	/* Use tunnel with the lowest tag for untagged VLAN id */
1523 	for (i = 0; i < RADIUS_TUNNEL_TAGS; i++) {
1524 		tun = &tunnel[i];
1525 		if (tun->tag_used &&
1526 		    tun->type == RADIUS_TUNNEL_TYPE_VLAN &&
1527 		    tun->medium_type == RADIUS_TUNNEL_MEDIUM_TYPE_802 &&
1528 		    tun->vlanid > 0) {
1529 			*untagged = tun->vlanid;
1530 			break;
1531 		}
1532 	}
1533 
1534 	if (taggedidx)
1535 		qsort(tagged, taggedidx, sizeof(int), cmp_int);
1536 
1537 	if (*untagged > 0 || taggedidx)
1538 		return 1;
1539 	return 0;
1540 }
1541 
1542 
1543 /**
1544  * radius_msg_get_tunnel_password - Parse RADIUS attribute Tunnel-Password
1545  * @msg: Received RADIUS message
1546  * @keylen: Length of returned password
1547  * @secret: RADIUS shared secret
1548  * @secret_len: Length of secret
1549  * @sent_msg: Sent RADIUS message
1550  * @n: Number of password attribute to return (starting with 0)
1551  * Returns: Pointer to n-th password (free with os_free) or %NULL
1552  */
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)1553 char * radius_msg_get_tunnel_password(struct radius_msg *msg, int *keylen,
1554 				      const u8 *secret, size_t secret_len,
1555 				      struct radius_msg *sent_msg, size_t n)
1556 {
1557 	u8 *buf = NULL;
1558 	size_t buflen;
1559 	const u8 *salt;
1560 	u8 *str;
1561 	const u8 *addr[3];
1562 	size_t len[3];
1563 	u8 hash[16];
1564 	u8 *pos;
1565 	size_t i, j = 0;
1566 	struct radius_attr_hdr *attr;
1567 	const u8 *data;
1568 	size_t dlen;
1569 	const u8 *fdata = NULL; /* points to found item */
1570 	size_t fdlen = -1;
1571 	char *ret = NULL;
1572 
1573 	/* find n-th valid Tunnel-Password attribute */
1574 	for (i = 0; i < msg->attr_used; i++) {
1575 		attr = radius_get_attr_hdr(msg, i);
1576 		if (attr == NULL ||
1577 		    attr->type != RADIUS_ATTR_TUNNEL_PASSWORD) {
1578 			continue;
1579 		}
1580 		if (attr->length <= 5)
1581 			continue;
1582 		data = (const u8 *) (attr + 1);
1583 		dlen = attr->length - sizeof(*attr);
1584 		if (dlen <= 3 || dlen % 16 != 3)
1585 			continue;
1586 		j++;
1587 		if (j <= n)
1588 			continue;
1589 
1590 		fdata = data;
1591 		fdlen = dlen;
1592 		break;
1593 	}
1594 	if (fdata == NULL)
1595 		goto out;
1596 
1597 	/* alloc writable memory for decryption */
1598 	buf = os_memdup(fdata, fdlen);
1599 	if (buf == NULL)
1600 		goto out;
1601 	buflen = fdlen;
1602 
1603 	/* init pointers */
1604 	salt = buf + 1;
1605 	str = buf + 3;
1606 
1607 	/* decrypt blocks */
1608 	pos = buf + buflen - 16; /* last block */
1609 	while (pos >= str + 16) { /* all but the first block */
1610 		addr[0] = secret;
1611 		len[0] = secret_len;
1612 		addr[1] = pos - 16;
1613 		len[1] = 16;
1614 		md5_vector(2, addr, len, hash);
1615 
1616 		for (i = 0; i < 16; i++)
1617 			pos[i] ^= hash[i];
1618 
1619 		pos -= 16;
1620 	}
1621 
1622 	/* decrypt first block */
1623 	if (str != pos)
1624 		goto out;
1625 	addr[0] = secret;
1626 	len[0] = secret_len;
1627 	addr[1] = sent_msg->hdr->authenticator;
1628 	len[1] = 16;
1629 	addr[2] = salt;
1630 	len[2] = 2;
1631 	md5_vector(3, addr, len, hash);
1632 
1633 	for (i = 0; i < 16; i++)
1634 		pos[i] ^= hash[i];
1635 
1636 	/* derive plaintext length from first subfield */
1637 	*keylen = (unsigned char) str[0];
1638 	if ((u8 *) (str + *keylen) >= (u8 *) (buf + buflen)) {
1639 		/* decryption error - invalid key length */
1640 		goto out;
1641 	}
1642 	if (*keylen == 0) {
1643 		/* empty password */
1644 		goto out;
1645 	}
1646 
1647 	/* copy passphrase into new buffer */
1648 	ret = os_malloc(*keylen);
1649 	if (ret)
1650 		os_memcpy(ret, str + 1, *keylen);
1651 
1652 out:
1653 	/* return new buffer */
1654 	os_free(buf);
1655 	return ret;
1656 }
1657 
1658 
radius_free_class(struct radius_class_data * c)1659 void radius_free_class(struct radius_class_data *c)
1660 {
1661 	size_t i;
1662 	if (c == NULL)
1663 		return;
1664 	for (i = 0; i < c->count; i++)
1665 		os_free(c->attr[i].data);
1666 	os_free(c->attr);
1667 	c->attr = NULL;
1668 	c->count = 0;
1669 }
1670 
1671 
radius_copy_class(struct radius_class_data * dst,const struct radius_class_data * src)1672 int radius_copy_class(struct radius_class_data *dst,
1673 		      const struct radius_class_data *src)
1674 {
1675 	size_t i;
1676 
1677 	if (src->attr == NULL)
1678 		return 0;
1679 
1680 	dst->attr = os_calloc(src->count, sizeof(struct radius_attr_data));
1681 	if (dst->attr == NULL)
1682 		return -1;
1683 
1684 	dst->count = 0;
1685 
1686 	for (i = 0; i < src->count; i++) {
1687 		dst->attr[i].data = os_memdup(src->attr[i].data,
1688 					      src->attr[i].len);
1689 		if (dst->attr[i].data == NULL)
1690 			break;
1691 		dst->count++;
1692 		dst->attr[i].len = src->attr[i].len;
1693 	}
1694 
1695 	return 0;
1696 }
1697 
1698 
radius_msg_find_unlisted_attr(struct radius_msg * msg,u8 * attrs)1699 u8 radius_msg_find_unlisted_attr(struct radius_msg *msg, u8 *attrs)
1700 {
1701 	size_t i, j;
1702 	struct radius_attr_hdr *attr;
1703 
1704 	for (i = 0; i < msg->attr_used; i++) {
1705 		attr = radius_get_attr_hdr(msg, i);
1706 
1707 		for (j = 0; attrs[j]; j++) {
1708 			if (attr->type == attrs[j])
1709 				break;
1710 		}
1711 
1712 		if (attrs[j] == 0)
1713 			return attr->type; /* unlisted attr */
1714 	}
1715 
1716 	return 0;
1717 }
1718 
1719 
radius_gen_session_id(u8 * id,size_t len)1720 int radius_gen_session_id(u8 *id, size_t len)
1721 {
1722 	/*
1723 	 * Acct-Session-Id and Acct-Multi-Session-Id should be globally and
1724 	 * temporarily unique. A high quality random number is required
1725 	 * therefore. This could be be improved by switching to a GUID.
1726 	 */
1727 	return os_get_random(id, len);
1728 }
1729