1 /*-
2 * Copyright 1998 Juniper Networks, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/lib/libradius/radlib.c 339270 2018-10-09 21:28:26Z gjb $
27 */
28
29 #include <sys/cdefs.h>
30
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <sys/time.h>
34 #include <netinet/in.h>
35 #include <arpa/inet.h>
36 #ifdef WITH_SSL
37 #include <openssl/hmac.h>
38 #include <openssl/md5.h>
39 #define MD5Init MD5_Init
40 #define MD5Update MD5_Update
41 #define MD5Final MD5_Final
42 #else
43 #define MD5_DIGEST_LENGTH 16
44 #include <md5.h>
45 #endif
46
47 #define MAX_FIELDS 7
48
49 /* We need the MPPE_KEY_LEN define */
50 #ifdef WANT_NETGRAPH7
51 #include <netgraph7/mppc/ng_mppc.h>
52 #else
53 #include <netgraph/mppc/ng_mppc.h>
54 #endif
55
56 #include <errno.h>
57 #include <netdb.h>
58 #include <stdarg.h>
59 #include <stddef.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <unistd.h>
64
65 #include "radlib_private.h"
66
67 static void clear_password(struct rad_handle *);
68 static void generr(struct rad_handle *, const char *, ...)
69 __printflike(2, 3);
70 static void insert_scrambled_password(struct rad_handle *, int);
71 static void insert_request_authenticator(struct rad_handle *, int);
72 static void insert_message_authenticator(struct rad_handle *, int);
73 static int is_valid_response(struct rad_handle *, int,
74 const struct sockaddr_in *);
75 static int put_password_attr(struct rad_handle *, int,
76 const void *, size_t);
77 static int put_raw_attr(struct rad_handle *, int,
78 const void *, size_t);
79 static int split(char *, const char *[], int, char *, size_t);
80
81 static void
clear_password(struct rad_handle * h)82 clear_password(struct rad_handle *h)
83 {
84 if (h->pass_len != 0) {
85 memset(h->pass, 0, h->pass_len);
86 h->pass_len = 0;
87 }
88 h->pass_pos = 0;
89 }
90
91 static void
generr(struct rad_handle * h,const char * format,...)92 generr(struct rad_handle *h, const char *format, ...)
93 {
94 va_list ap;
95
96 va_start(ap, format);
97 vsnprintf(h->errmsg, ERRSIZE, format, ap);
98 va_end(ap);
99 }
100
101 static void
insert_scrambled_password(struct rad_handle * h,int srv)102 insert_scrambled_password(struct rad_handle *h, int srv)
103 {
104 MD5_CTX ctx;
105 unsigned char md5[MD5_DIGEST_LENGTH];
106 const struct rad_server *srvp;
107 int padded_len;
108 int pos;
109
110 srvp = &h->servers[srv];
111 padded_len = h->pass_len == 0 ? 16 : (h->pass_len+15) & ~0xf;
112
113 memcpy(md5, &h->out[POS_AUTH], LEN_AUTH);
114 for (pos = 0; pos < padded_len; pos += 16) {
115 int i;
116
117 /* Calculate the new scrambler */
118 MD5Init(&ctx);
119 MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
120 MD5Update(&ctx, md5, 16);
121 MD5Final(md5, &ctx);
122
123 /*
124 * Mix in the current chunk of the password, and copy
125 * the result into the right place in the request. Also
126 * modify the scrambler in place, since we will use this
127 * in calculating the scrambler for next time.
128 */
129 for (i = 0; i < 16; i++)
130 h->out[h->pass_pos + pos + i] =
131 md5[i] ^= h->pass[pos + i];
132 }
133 }
134
135 static void
insert_request_authenticator(struct rad_handle * h,int resp)136 insert_request_authenticator(struct rad_handle *h, int resp)
137 {
138 MD5_CTX ctx;
139 const struct rad_server *srvp;
140
141 srvp = &h->servers[h->srv];
142
143 /* Create the request authenticator */
144 MD5Init(&ctx);
145 MD5Update(&ctx, &h->out[POS_CODE], POS_AUTH - POS_CODE);
146 if (resp)
147 MD5Update(&ctx, &h->in[POS_AUTH], LEN_AUTH);
148 else
149 MD5Update(&ctx, &h->out[POS_AUTH], LEN_AUTH);
150 MD5Update(&ctx, &h->out[POS_ATTRS], h->out_len - POS_ATTRS);
151 MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
152 MD5Final(&h->out[POS_AUTH], &ctx);
153 }
154
155 static void
insert_message_authenticator(struct rad_handle * h,int resp)156 insert_message_authenticator(struct rad_handle *h, int resp)
157 {
158 #ifdef WITH_SSL
159 u_char md[EVP_MAX_MD_SIZE];
160 u_int md_len;
161 const struct rad_server *srvp;
162 HMAC_CTX *ctx;
163 srvp = &h->servers[h->srv];
164
165 if (h->authentic_pos != 0) {
166 ctx = HMAC_CTX_new();
167 HMAC_Init_ex(ctx, srvp->secret, strlen(srvp->secret), EVP_md5(), NULL);
168 HMAC_Update(ctx, &h->out[POS_CODE], POS_AUTH - POS_CODE);
169 if (resp)
170 HMAC_Update(ctx, &h->in[POS_AUTH], LEN_AUTH);
171 else
172 HMAC_Update(ctx, &h->out[POS_AUTH], LEN_AUTH);
173 HMAC_Update(ctx, &h->out[POS_ATTRS],
174 h->out_len - POS_ATTRS);
175 HMAC_Final(ctx, md, &md_len);
176 HMAC_CTX_free(ctx);
177 memcpy(&h->out[h->authentic_pos + 2], md, md_len);
178 }
179 #endif
180 }
181
182 /*
183 * Return true if the current response is valid for a request to the
184 * specified server.
185 */
186 static int
is_valid_response(struct rad_handle * h,int srv,const struct sockaddr_in * from)187 is_valid_response(struct rad_handle *h, int srv,
188 const struct sockaddr_in *from)
189 {
190 MD5_CTX ctx;
191 unsigned char md5[MD5_DIGEST_LENGTH];
192 const struct rad_server *srvp;
193 int len;
194 #ifdef WITH_SSL
195 HMAC_CTX *hctx;
196 u_char resp[MSGSIZE], md[EVP_MAX_MD_SIZE];
197 u_int md_len;
198 int pos;
199 #endif
200
201 srvp = &h->servers[srv];
202
203 /* Check the source address */
204 if (from->sin_family != srvp->addr.sin_family ||
205 from->sin_addr.s_addr != srvp->addr.sin_addr.s_addr ||
206 from->sin_port != srvp->addr.sin_port)
207 return 0;
208
209 /* Check the message length */
210 if (h->in_len < POS_ATTRS)
211 return 0;
212 len = h->in[POS_LENGTH] << 8 | h->in[POS_LENGTH+1];
213 if (len > h->in_len)
214 return 0;
215
216 /* Check the response authenticator */
217 MD5Init(&ctx);
218 MD5Update(&ctx, &h->in[POS_CODE], POS_AUTH - POS_CODE);
219 MD5Update(&ctx, &h->out[POS_AUTH], LEN_AUTH);
220 MD5Update(&ctx, &h->in[POS_ATTRS], len - POS_ATTRS);
221 MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
222 MD5Final(md5, &ctx);
223 if (memcmp(&h->in[POS_AUTH], md5, sizeof md5) != 0)
224 return 0;
225
226 #ifdef WITH_SSL
227 /*
228 * For non accounting responses check the message authenticator,
229 * if any.
230 */
231 if (h->in[POS_CODE] != RAD_ACCOUNTING_RESPONSE) {
232
233 memcpy(resp, h->in, MSGSIZE);
234 pos = POS_ATTRS;
235
236 /* Search and verify the Message-Authenticator */
237 hctx = HMAC_CTX_new();
238 while (pos < len - 2) {
239
240 if (h->in[pos] == RAD_MESSAGE_AUTHENTIC) {
241 /* zero fill the Message-Authenticator */
242 memset(&resp[pos + 2], 0, MD5_DIGEST_LENGTH);
243
244 HMAC_Init_ex(hctx, srvp->secret,
245 strlen(srvp->secret), EVP_md5(), NULL);
246 HMAC_Update(hctx, &h->in[POS_CODE],
247 POS_AUTH - POS_CODE);
248 HMAC_Update(hctx, &h->out[POS_AUTH],
249 LEN_AUTH);
250 HMAC_Update(hctx, &resp[POS_ATTRS],
251 h->in_len - POS_ATTRS);
252 HMAC_Final(hctx, md, &md_len);
253 HMAC_CTX_reset(hctx);
254 if (memcmp(md, &h->in[pos + 2],
255 MD5_DIGEST_LENGTH) != 0) {
256 HMAC_CTX_free(hctx);
257 return 0;
258 }
259 break;
260 }
261 pos += h->in[pos + 1];
262 }
263 HMAC_CTX_free(hctx);
264 }
265 #endif
266 return 1;
267 }
268
269 /*
270 * Return true if the current request is valid for the specified server.
271 */
272 static int
is_valid_request(struct rad_handle * h)273 is_valid_request(struct rad_handle *h)
274 {
275 MD5_CTX ctx;
276 unsigned char md5[MD5_DIGEST_LENGTH];
277 const struct rad_server *srvp;
278 int len;
279 #ifdef WITH_SSL
280 HMAC_CTX *hctx;
281 u_char resp[MSGSIZE], md[EVP_MAX_MD_SIZE];
282 u_int md_len;
283 int pos;
284 #endif
285
286 srvp = &h->servers[h->srv];
287
288 /* Check the message length */
289 if (h->in_len < POS_ATTRS)
290 return (0);
291 len = h->in[POS_LENGTH] << 8 | h->in[POS_LENGTH+1];
292 if (len > h->in_len)
293 return (0);
294
295 if (h->in[POS_CODE] != RAD_ACCESS_REQUEST) {
296 uint32_t zeroes[4] = { 0, 0, 0, 0 };
297 /* Check the request authenticator */
298 MD5Init(&ctx);
299 MD5Update(&ctx, &h->in[POS_CODE], POS_AUTH - POS_CODE);
300 MD5Update(&ctx, zeroes, LEN_AUTH);
301 MD5Update(&ctx, &h->in[POS_ATTRS], len - POS_ATTRS);
302 MD5Update(&ctx, srvp->secret, strlen(srvp->secret));
303 MD5Final(md5, &ctx);
304 if (memcmp(&h->in[POS_AUTH], md5, sizeof md5) != 0)
305 return (0);
306 }
307
308 #ifdef WITH_SSL
309 /* Search and verify the Message-Authenticator */
310 pos = POS_ATTRS;
311 hctx = HMAC_CTX_new();
312 while (pos < len - 2) {
313 if (h->in[pos] == RAD_MESSAGE_AUTHENTIC) {
314 memcpy(resp, h->in, MSGSIZE);
315 /* zero fill the Request-Authenticator */
316 if (h->in[POS_CODE] != RAD_ACCESS_REQUEST)
317 memset(&resp[POS_AUTH], 0, LEN_AUTH);
318 /* zero fill the Message-Authenticator */
319 memset(&resp[pos + 2], 0, MD5_DIGEST_LENGTH);
320
321 HMAC_Init_ex(hctx, srvp->secret,
322 strlen(srvp->secret), EVP_md5(), NULL);
323 HMAC_Update(hctx, resp, h->in_len);
324 HMAC_Final(hctx, md, &md_len);
325 HMAC_CTX_reset(hctx);
326 if (memcmp(md, &h->in[pos + 2],
327 MD5_DIGEST_LENGTH) != 0) {
328 HMAC_CTX_free(hctx);
329 return (0);
330 }
331 break;
332 }
333 pos += h->in[pos + 1];
334 }
335 HMAC_CTX_free(hctx);
336 #endif
337 return (1);
338 }
339
340 static int
put_password_attr(struct rad_handle * h,int type,const void * value,size_t len)341 put_password_attr(struct rad_handle *h, int type, const void *value, size_t len)
342 {
343 int padded_len;
344 int pad_len;
345
346 if (h->pass_pos != 0) {
347 generr(h, "Multiple User-Password attributes specified");
348 return -1;
349 }
350 if (len > PASSSIZE)
351 len = PASSSIZE;
352 padded_len = len == 0 ? 16 : (len+15) & ~0xf;
353 pad_len = padded_len - len;
354
355 /*
356 * Put in a place-holder attribute containing all zeros, and
357 * remember where it is so we can fill it in later.
358 */
359 clear_password(h);
360 put_raw_attr(h, type, h->pass, padded_len);
361 h->pass_pos = h->out_len - padded_len;
362
363 /* Save the cleartext password, padded as necessary */
364 memcpy(h->pass, value, len);
365 h->pass_len = len;
366 memset(h->pass + len, 0, pad_len);
367 return 0;
368 }
369
370 static int
put_raw_attr(struct rad_handle * h,int type,const void * value,size_t len)371 put_raw_attr(struct rad_handle *h, int type, const void *value, size_t len)
372 {
373 if (len > 253) {
374 generr(h, "Attribute too long");
375 return -1;
376 }
377 if (h->out_len + 2 + len > MSGSIZE) {
378 generr(h, "Maximum message length exceeded");
379 return -1;
380 }
381 h->out[h->out_len++] = type;
382 h->out[h->out_len++] = len + 2;
383 memcpy(&h->out[h->out_len], value, len);
384 h->out_len += len;
385 return 0;
386 }
387
388 int
rad_add_server(struct rad_handle * h,const char * host,int port,const char * secret,int timeout,int tries)389 rad_add_server(struct rad_handle *h, const char *host, int port,
390 const char *secret, int timeout, int tries)
391 {
392 struct in_addr bindto;
393 bindto.s_addr = INADDR_ANY;
394
395 return rad_add_server_ex(h, host, port, secret, timeout, tries,
396 DEAD_TIME, &bindto);
397 }
398
399 int
rad_add_server_ex(struct rad_handle * h,const char * host,int port,const char * secret,int timeout,int tries,int dead_time,struct in_addr * bindto)400 rad_add_server_ex(struct rad_handle *h, const char *host, int port,
401 const char *secret, int timeout, int tries, int dead_time,
402 struct in_addr *bindto)
403 {
404 struct rad_server *srvp;
405
406 if (h->num_servers >= MAXSERVERS) {
407 generr(h, "Too many RADIUS servers specified");
408 return -1;
409 }
410 srvp = &h->servers[h->num_servers];
411
412 memset(&srvp->addr, 0, sizeof srvp->addr);
413 srvp->addr.sin_len = sizeof srvp->addr;
414 srvp->addr.sin_family = AF_INET;
415 if (!inet_aton(host, &srvp->addr.sin_addr)) {
416 struct hostent *hent;
417
418 if ((hent = gethostbyname(host)) == NULL) {
419 generr(h, "%s: host not found", host);
420 return -1;
421 }
422 memcpy(&srvp->addr.sin_addr, hent->h_addr,
423 sizeof srvp->addr.sin_addr);
424 }
425 if (port != 0)
426 srvp->addr.sin_port = htons((u_short)port);
427 else {
428 struct servent *sent;
429
430 if (h->type == RADIUS_AUTH)
431 srvp->addr.sin_port =
432 (sent = getservbyname("radius", "udp")) != NULL ?
433 sent->s_port : htons(RADIUS_PORT);
434 else
435 srvp->addr.sin_port =
436 (sent = getservbyname("radacct", "udp")) != NULL ?
437 sent->s_port : htons(RADACCT_PORT);
438 }
439 if ((srvp->secret = strdup(secret)) == NULL) {
440 generr(h, "Out of memory");
441 return -1;
442 }
443 srvp->timeout = timeout;
444 srvp->max_tries = tries;
445 srvp->num_tries = 0;
446 srvp->is_dead = 0;
447 srvp->dead_time = dead_time;
448 srvp->next_probe = 0;
449 srvp->bindto = bindto->s_addr;
450 h->num_servers++;
451 return 0;
452 }
453
454 void
rad_close(struct rad_handle * h)455 rad_close(struct rad_handle *h)
456 {
457 int srv;
458
459 if (h->fd != -1)
460 close(h->fd);
461 for (srv = 0; srv < h->num_servers; srv++) {
462 memset(h->servers[srv].secret, 0,
463 strlen(h->servers[srv].secret));
464 free(h->servers[srv].secret);
465 }
466 clear_password(h);
467 free(h);
468 }
469
470 void
rad_bind_to(struct rad_handle * h,in_addr_t addr)471 rad_bind_to(struct rad_handle *h, in_addr_t addr)
472 {
473
474 h->bindto = addr;
475 }
476
477 int
rad_config(struct rad_handle * h,const char * path)478 rad_config(struct rad_handle *h, const char *path)
479 {
480 FILE *fp;
481 char buf[MAXCONFLINE];
482 int linenum;
483 int retval;
484
485 if (path == NULL)
486 path = PATH_RADIUS_CONF;
487 if ((fp = fopen(path, "r")) == NULL) {
488 generr(h, "Cannot open \"%s\": %s", path, strerror(errno));
489 return -1;
490 }
491 retval = 0;
492 linenum = 0;
493 while (fgets(buf, sizeof buf, fp) != NULL) {
494 int len;
495 const char *fields[MAX_FIELDS];
496 int nfields;
497 char msg[ERRSIZE];
498 const char *type;
499 const char *host;
500 const char *port_str;
501 const char *secret;
502 const char *timeout_str;
503 const char *maxtries_str;
504 const char *dead_time_str;
505 const char *bindto_str;
506 char *res, *host_dup;
507 char *end;
508 const char *wanttype;
509 unsigned long timeout;
510 unsigned long maxtries;
511 unsigned long dead_time;
512 int port;
513 struct in_addr bindto;
514 int i;
515
516 linenum++;
517 len = strlen(buf);
518 /* We know len > 0, else fgets would have returned NULL. */
519 if (buf[len - 1] != '\n') {
520 if (len == sizeof buf - 1)
521 generr(h, "%s:%d: line too long", path,
522 linenum);
523 else
524 generr(h, "%s:%d: missing newline", path,
525 linenum);
526 retval = -1;
527 break;
528 }
529 buf[len - 1] = '\0';
530
531 /* Extract the fields from the line. */
532 nfields = split(buf, fields, MAX_FIELDS, msg, sizeof msg);
533 if (nfields == -1) {
534 generr(h, "%s:%d: %s", path, linenum, msg);
535 retval = -1;
536 break;
537 }
538 if (nfields == 0)
539 continue;
540 /*
541 * The first field should contain "auth" or "acct" for
542 * authentication or accounting, respectively. But older
543 * versions of the file didn't have that field. Default
544 * it to "auth" for backward compatibility.
545 */
546 if (strcmp(fields[0], "auth") != 0 &&
547 strcmp(fields[0], "acct") != 0) {
548 if (nfields >= MAX_FIELDS) {
549 generr(h, "%s:%d: invalid service type", path,
550 linenum);
551 retval = -1;
552 break;
553 }
554 nfields++;
555 for (i = nfields; --i > 0; )
556 fields[i] = fields[i - 1];
557 fields[0] = "auth";
558 }
559 if (nfields < 3) {
560 generr(h, "%s:%d: missing shared secret", path,
561 linenum);
562 retval = -1;
563 break;
564 }
565 type = fields[0];
566 host = fields[1];
567 secret = fields[2];
568 timeout_str = fields[3];
569 maxtries_str = fields[4];
570 dead_time_str = fields[5];
571 bindto_str = fields[6];
572
573 /* Ignore the line if it is for the wrong service type. */
574 wanttype = h->type == RADIUS_AUTH ? "auth" : "acct";
575 if (strcmp(type, wanttype) != 0)
576 continue;
577
578 /* Parse and validate the fields. */
579 if ((host_dup = strdup(host)) == NULL) {
580 generr(h, "%s:%d: malloc failed", path, linenum);
581 retval = -1;
582 break;
583 }
584 res = host_dup;
585 host = strsep(&res, ":");
586 port_str = strsep(&res, ":");
587 if (port_str != NULL) {
588 port = strtoul(port_str, &end, 10);
589 if (*end != '\0') {
590 free(host_dup);
591 generr(h, "%s:%d: invalid port", path,
592 linenum);
593 retval = -1;
594 break;
595 }
596 } else
597 port = 0;
598 if (timeout_str != NULL) {
599 timeout = strtoul(timeout_str, &end, 10);
600 if (*end != '\0') {
601 free(host_dup);
602 generr(h, "%s:%d: invalid timeout", path,
603 linenum);
604 retval = -1;
605 break;
606 }
607 } else
608 timeout = TIMEOUT;
609 if (maxtries_str != NULL) {
610 maxtries = strtoul(maxtries_str, &end, 10);
611 if (*end != '\0') {
612 free(host_dup);
613 generr(h, "%s:%d: invalid maxtries", path,
614 linenum);
615 retval = -1;
616 break;
617 }
618 } else
619 maxtries = MAXTRIES;
620
621 if (dead_time_str != NULL) {
622 dead_time = strtoul(dead_time_str, &end, 10);
623 if (*end != '\0') {
624 free(host_dup);
625 generr(h, "%s:%d: invalid dead_time", path,
626 linenum);
627 retval = -1;
628 break;
629 }
630 } else
631 dead_time = DEAD_TIME;
632
633 if (bindto_str != NULL) {
634 bindto.s_addr = inet_addr(bindto_str);
635 if (bindto.s_addr == INADDR_NONE) {
636 free(host_dup);
637 generr(h, "%s:%d: invalid bindto", path,
638 linenum);
639 retval = -1;
640 break;
641 }
642 } else
643 bindto.s_addr = INADDR_ANY;
644
645 if (rad_add_server_ex(h, host, port, secret, timeout, maxtries,
646 dead_time, &bindto) == -1) {
647 free(host_dup);
648 strcpy(msg, h->errmsg);
649 generr(h, "%s:%d: %s", path, linenum, msg);
650 retval = -1;
651 break;
652 }
653 free(host_dup);
654 }
655 /* Clear out the buffer to wipe a possible copy of a shared secret */
656 memset(buf, 0, sizeof buf);
657 fclose(fp);
658 return retval;
659 }
660
661 /*
662 * rad_init_send_request() must have previously been called.
663 * Returns:
664 * 0 The application should select on *fd with a timeout of tv before
665 * calling rad_continue_send_request again.
666 * < 0 Failure
667 * > 0 Success
668 */
669 int
rad_continue_send_request(struct rad_handle * h,int selected,int * fd,struct timeval * tv)670 rad_continue_send_request(struct rad_handle *h, int selected, int *fd,
671 struct timeval *tv)
672 {
673 int n, cur_srv;
674 time_t now;
675 struct sockaddr_in sin;
676
677 if (h->type == RADIUS_SERVER) {
678 generr(h, "denied function call");
679 return (-1);
680 }
681 if (selected) {
682 struct sockaddr_in from;
683 socklen_t fromlen;
684
685 fromlen = sizeof from;
686 h->in_len = recvfrom(h->fd, h->in,
687 MSGSIZE, MSG_WAITALL, (struct sockaddr *)&from, &fromlen);
688 if (h->in_len == -1) {
689 generr(h, "recvfrom: %s", strerror(errno));
690 return -1;
691 }
692 if (is_valid_response(h, h->srv, &from)) {
693 h->in_len = h->in[POS_LENGTH] << 8 |
694 h->in[POS_LENGTH+1];
695 h->in_pos = POS_ATTRS;
696 return h->in[POS_CODE];
697 }
698 }
699
700 /*
701 * Scan round-robin to the next server that has some
702 * tries left. There is guaranteed to be one, or we
703 * would have exited this loop by now.
704 */
705 cur_srv = h->srv;
706 now = time(NULL);
707 if (h->servers[h->srv].num_tries >= h->servers[h->srv].max_tries) {
708 /* Set next probe time for this server */
709 if (h->servers[h->srv].dead_time) {
710 h->servers[h->srv].is_dead = 1;
711 h->servers[h->srv].next_probe = now +
712 h->servers[h->srv].dead_time;
713 }
714 do {
715 h->srv++;
716 if (h->srv >= h->num_servers)
717 h->srv = 0;
718 if (h->servers[h->srv].is_dead == 0)
719 break;
720 if (h->servers[h->srv].dead_time &&
721 h->servers[h->srv].next_probe <= now) {
722 h->servers[h->srv].is_dead = 0;
723 h->servers[h->srv].num_tries = 0;
724 break;
725 }
726 } while (h->srv != cur_srv);
727
728 if (h->srv == cur_srv) {
729 generr(h, "No valid RADIUS responses received");
730 return (-1);
731 }
732 }
733
734 /* Rebind */
735 if (h->bindto != h->servers[h->srv].bindto) {
736 h->bindto = h->servers[h->srv].bindto;
737 close(h->fd);
738 if ((h->fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) {
739 generr(h, "Cannot create socket: %s", strerror(errno));
740 return -1;
741 }
742 memset(&sin, 0, sizeof sin);
743 sin.sin_len = sizeof sin;
744 sin.sin_family = AF_INET;
745 sin.sin_addr.s_addr = h->bindto;
746 sin.sin_port = 0;
747 if (bind(h->fd, (const struct sockaddr *)&sin,
748 sizeof sin) == -1) {
749 generr(h, "bind: %s", strerror(errno));
750 close(h->fd);
751 h->fd = -1;
752 return (-1);
753 }
754 }
755
756 if (h->out[POS_CODE] == RAD_ACCESS_REQUEST) {
757 /* Insert the scrambled password into the request */
758 if (h->pass_pos != 0)
759 insert_scrambled_password(h, h->srv);
760 }
761 insert_message_authenticator(h, 0);
762
763 if (h->out[POS_CODE] != RAD_ACCESS_REQUEST) {
764 /* Insert the request authenticator into the request */
765 memset(&h->out[POS_AUTH], 0, LEN_AUTH);
766 insert_request_authenticator(h, 0);
767 }
768
769 /* Send the request */
770 n = sendto(h->fd, h->out, h->out_len, 0,
771 (const struct sockaddr *)&h->servers[h->srv].addr,
772 sizeof h->servers[h->srv].addr);
773 if (n != h->out_len)
774 tv->tv_sec = 1; /* Do not wait full timeout if send failed. */
775 else
776 tv->tv_sec = h->servers[h->srv].timeout;
777 h->servers[h->srv].num_tries++;
778 tv->tv_usec = 0;
779 *fd = h->fd;
780
781 return 0;
782 }
783
784 int
rad_receive_request(struct rad_handle * h)785 rad_receive_request(struct rad_handle *h)
786 {
787 struct sockaddr_in from;
788 socklen_t fromlen;
789 int n;
790
791 if (h->type != RADIUS_SERVER) {
792 generr(h, "denied function call");
793 return (-1);
794 }
795 h->srv = -1;
796 fromlen = sizeof(from);
797 h->in_len = recvfrom(h->fd, h->in,
798 MSGSIZE, MSG_WAITALL, (struct sockaddr *)&from, &fromlen);
799 if (h->in_len == -1) {
800 generr(h, "recvfrom: %s", strerror(errno));
801 return (-1);
802 }
803 for (n = 0; n < h->num_servers; n++) {
804 if (h->servers[n].addr.sin_addr.s_addr == from.sin_addr.s_addr) {
805 h->servers[n].addr.sin_port = from.sin_port;
806 h->srv = n;
807 break;
808 }
809 }
810 if (h->srv == -1)
811 return (-2);
812 if (is_valid_request(h)) {
813 h->in_len = h->in[POS_LENGTH] << 8 |
814 h->in[POS_LENGTH+1];
815 h->in_pos = POS_ATTRS;
816 return (h->in[POS_CODE]);
817 }
818 return (-3);
819 }
820
821 int
rad_send_response(struct rad_handle * h)822 rad_send_response(struct rad_handle *h)
823 {
824 int n;
825
826 if (h->type != RADIUS_SERVER) {
827 generr(h, "denied function call");
828 return (-1);
829 }
830 /* Fill in the length field in the message */
831 h->out[POS_LENGTH] = h->out_len >> 8;
832 h->out[POS_LENGTH+1] = h->out_len;
833
834 insert_message_authenticator(h,
835 (h->in[POS_CODE] == RAD_ACCESS_REQUEST) ? 1 : 0);
836 insert_request_authenticator(h, 1);
837
838 /* Send the request */
839 n = sendto(h->fd, h->out, h->out_len, 0,
840 (const struct sockaddr *)&h->servers[h->srv].addr,
841 sizeof h->servers[h->srv].addr);
842 if (n != h->out_len) {
843 if (n == -1)
844 generr(h, "sendto: %s", strerror(errno));
845 else
846 generr(h, "sendto: short write");
847 return -1;
848 }
849
850 return 0;
851 }
852
853 int
rad_create_request(struct rad_handle * h,int code)854 rad_create_request(struct rad_handle *h, int code)
855 {
856 int i;
857
858 if (h->type == RADIUS_SERVER) {
859 generr(h, "denied function call");
860 return (-1);
861 }
862 if (h->num_servers == 0) {
863 generr(h, "No RADIUS servers specified");
864 return (-1);
865 }
866 h->out[POS_CODE] = code;
867 h->out[POS_IDENT] = ++h->ident;
868 if (code == RAD_ACCESS_REQUEST) {
869 /* Create a random authenticator */
870 for (i = 0; i < LEN_AUTH; i += 2) {
871 long r;
872 r = random();
873 h->out[POS_AUTH+i] = (u_char)r;
874 h->out[POS_AUTH+i+1] = (u_char)(r >> 8);
875 }
876 } else
877 memset(&h->out[POS_AUTH], 0, LEN_AUTH);
878 h->out_len = POS_ATTRS;
879 clear_password(h);
880 h->authentic_pos = 0;
881 h->out_created = 1;
882 return 0;
883 }
884
885 int
rad_create_response(struct rad_handle * h,int code)886 rad_create_response(struct rad_handle *h, int code)
887 {
888
889 if (h->type != RADIUS_SERVER) {
890 generr(h, "denied function call");
891 return (-1);
892 }
893 h->out[POS_CODE] = code;
894 h->out[POS_IDENT] = h->in[POS_IDENT];
895 memset(&h->out[POS_AUTH], 0, LEN_AUTH);
896 h->out_len = POS_ATTRS;
897 clear_password(h);
898 h->authentic_pos = 0;
899 h->out_created = 1;
900 return 0;
901 }
902
903 struct in_addr
rad_cvt_addr(const void * data)904 rad_cvt_addr(const void *data)
905 {
906 struct in_addr value;
907
908 memcpy(&value.s_addr, data, sizeof value.s_addr);
909 return value;
910 }
911
912 struct in6_addr
rad_cvt_addr6(const void * data)913 rad_cvt_addr6(const void *data)
914 {
915 struct in6_addr value;
916
917 memcpy(&value.s6_addr, data, sizeof value.s6_addr);
918 return value;
919 }
920
921 u_int32_t
rad_cvt_int(const void * data)922 rad_cvt_int(const void *data)
923 {
924 u_int32_t value;
925
926 memcpy(&value, data, sizeof value);
927 return ntohl(value);
928 }
929
930 char *
rad_cvt_string(const void * data,size_t len)931 rad_cvt_string(const void *data, size_t len)
932 {
933 char *s;
934
935 s = malloc(len + 1);
936 if (s != NULL) {
937 memcpy(s, data, len);
938 s[len] = '\0';
939 }
940 return s;
941 }
942
943 /*
944 * Returns the attribute type. If none are left, returns 0. On failure,
945 * returns -1.
946 */
947 int
rad_get_attr(struct rad_handle * h,const void ** value,size_t * len)948 rad_get_attr(struct rad_handle *h, const void **value, size_t *len)
949 {
950 int type;
951
952 if (h->in_pos >= h->in_len)
953 return 0;
954 if (h->in_pos + 2 > h->in_len) {
955 generr(h, "Malformed attribute in response");
956 return -1;
957 }
958 type = h->in[h->in_pos++];
959 *len = h->in[h->in_pos++] - 2;
960 if (h->in_pos + (int)*len > h->in_len) {
961 generr(h, "Malformed attribute in response");
962 return -1;
963 }
964 *value = &h->in[h->in_pos];
965 h->in_pos += *len;
966 return type;
967 }
968
969 /*
970 * Returns -1 on error, 0 to indicate no event and >0 for success
971 */
972 int
rad_init_send_request(struct rad_handle * h,int * fd,struct timeval * tv)973 rad_init_send_request(struct rad_handle *h, int *fd, struct timeval *tv)
974 {
975 int srv;
976 time_t now;
977 struct sockaddr_in sin;
978
979 if (h->type == RADIUS_SERVER) {
980 generr(h, "denied function call");
981 return (-1);
982 }
983 /* Make sure we have a socket to use */
984 if (h->fd == -1) {
985 if ((h->fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) {
986 generr(h, "Cannot create socket: %s", strerror(errno));
987 return -1;
988 }
989 memset(&sin, 0, sizeof sin);
990 sin.sin_len = sizeof sin;
991 sin.sin_family = AF_INET;
992 sin.sin_addr.s_addr = h->bindto;
993 sin.sin_port = htons(0);
994 if (bind(h->fd, (const struct sockaddr *)&sin,
995 sizeof sin) == -1) {
996 generr(h, "bind: %s", strerror(errno));
997 close(h->fd);
998 h->fd = -1;
999 return -1;
1000 }
1001 }
1002
1003 if (h->out[POS_CODE] != RAD_ACCESS_REQUEST) {
1004 /* Make sure no password given */
1005 if (h->pass_pos || h->chap_pass) {
1006 generr(h, "User or Chap Password"
1007 " in accounting request");
1008 return -1;
1009 }
1010 } else {
1011 if (h->eap_msg == 0) {
1012 /* Make sure the user gave us a password */
1013 if (h->pass_pos == 0 && !h->chap_pass) {
1014 generr(h, "No User or Chap Password"
1015 " attributes given");
1016 return -1;
1017 }
1018 if (h->pass_pos != 0 && h->chap_pass) {
1019 generr(h, "Both User and Chap Password"
1020 " attributes given");
1021 return -1;
1022 }
1023 }
1024 }
1025
1026 /* Fill in the length field in the message */
1027 h->out[POS_LENGTH] = h->out_len >> 8;
1028 h->out[POS_LENGTH+1] = h->out_len;
1029
1030 h->srv = 0;
1031 now = time(NULL);
1032 for (srv = 0; srv < h->num_servers; srv++)
1033 h->servers[srv].num_tries = 0;
1034 /* Find a first good server. */
1035 for (srv = 0; srv < h->num_servers; srv++) {
1036 if (h->servers[srv].is_dead == 0)
1037 break;
1038 if (h->servers[srv].dead_time &&
1039 h->servers[srv].next_probe <= now) {
1040 h->servers[srv].is_dead = 0;
1041 break;
1042 }
1043 h->srv++;
1044 }
1045
1046 /* If all servers was dead on the last probe, try from beginning */
1047 if (h->srv == h->num_servers) {
1048 for (srv = 0; srv < h->num_servers; srv++) {
1049 h->servers[srv].is_dead = 0;
1050 h->servers[srv].next_probe = 0;
1051 }
1052 h->srv = 0;
1053 }
1054
1055 return rad_continue_send_request(h, 0, fd, tv);
1056 }
1057
1058 /*
1059 * Create and initialize a rad_handle structure, and return it to the
1060 * caller. Can fail only if the necessary memory cannot be allocated.
1061 * In that case, it returns NULL.
1062 */
1063 struct rad_handle *
rad_auth_open(void)1064 rad_auth_open(void)
1065 {
1066 struct rad_handle *h;
1067
1068 h = (struct rad_handle *)malloc(sizeof(struct rad_handle));
1069 if (h != NULL) {
1070 srandomdev();
1071 h->fd = -1;
1072 h->num_servers = 0;
1073 h->ident = random();
1074 h->errmsg[0] = '\0';
1075 memset(h->pass, 0, sizeof h->pass);
1076 h->pass_len = 0;
1077 h->pass_pos = 0;
1078 h->chap_pass = 0;
1079 h->authentic_pos = 0;
1080 h->type = RADIUS_AUTH;
1081 h->out_created = 0;
1082 h->eap_msg = 0;
1083 h->bindto = INADDR_ANY;
1084 }
1085 return h;
1086 }
1087
1088 struct rad_handle *
rad_acct_open(void)1089 rad_acct_open(void)
1090 {
1091 struct rad_handle *h;
1092
1093 h = rad_open();
1094 if (h != NULL)
1095 h->type = RADIUS_ACCT;
1096 return h;
1097 }
1098
1099 struct rad_handle *
rad_server_open(int fd)1100 rad_server_open(int fd)
1101 {
1102 struct rad_handle *h;
1103
1104 h = rad_open();
1105 if (h != NULL) {
1106 h->type = RADIUS_SERVER;
1107 h->fd = fd;
1108 }
1109 return h;
1110 }
1111
1112 struct rad_handle *
rad_open(void)1113 rad_open(void)
1114 {
1115 return rad_auth_open();
1116 }
1117
1118 int
rad_put_addr(struct rad_handle * h,int type,struct in_addr addr)1119 rad_put_addr(struct rad_handle *h, int type, struct in_addr addr)
1120 {
1121 return rad_put_attr(h, type, &addr.s_addr, sizeof addr.s_addr);
1122 }
1123
1124 int
rad_put_addr6(struct rad_handle * h,int type,struct in6_addr addr)1125 rad_put_addr6(struct rad_handle *h, int type, struct in6_addr addr)
1126 {
1127
1128 return rad_put_attr(h, type, &addr.s6_addr, sizeof addr.s6_addr);
1129 }
1130
1131 int
rad_put_attr(struct rad_handle * h,int type,const void * value,size_t len)1132 rad_put_attr(struct rad_handle *h, int type, const void *value, size_t len)
1133 {
1134 int result;
1135
1136 if (!h->out_created) {
1137 generr(h, "Please call rad_create_request()"
1138 " before putting attributes");
1139 return -1;
1140 }
1141
1142 if (h->out[POS_CODE] == RAD_ACCOUNTING_REQUEST) {
1143 if (type == RAD_EAP_MESSAGE) {
1144 generr(h, "EAP-Message attribute is not valid"
1145 " in accounting requests");
1146 return -1;
1147 }
1148 }
1149
1150 /*
1151 * When proxying EAP Messages, the Message Authenticator
1152 * MUST be present; see RFC 3579.
1153 */
1154 if (type == RAD_EAP_MESSAGE) {
1155 if (rad_put_message_authentic(h) == -1)
1156 return -1;
1157 }
1158
1159 if (type == RAD_USER_PASSWORD) {
1160 result = put_password_attr(h, type, value, len);
1161 } else if (type == RAD_MESSAGE_AUTHENTIC) {
1162 result = rad_put_message_authentic(h);
1163 } else {
1164 result = put_raw_attr(h, type, value, len);
1165 if (result == 0) {
1166 if (type == RAD_CHAP_PASSWORD)
1167 h->chap_pass = 1;
1168 else if (type == RAD_EAP_MESSAGE)
1169 h->eap_msg = 1;
1170 }
1171 }
1172
1173 return result;
1174 }
1175
1176 int
rad_put_int(struct rad_handle * h,int type,u_int32_t value)1177 rad_put_int(struct rad_handle *h, int type, u_int32_t value)
1178 {
1179 u_int32_t nvalue;
1180
1181 nvalue = htonl(value);
1182 return rad_put_attr(h, type, &nvalue, sizeof nvalue);
1183 }
1184
1185 int
rad_put_string(struct rad_handle * h,int type,const char * str)1186 rad_put_string(struct rad_handle *h, int type, const char *str)
1187 {
1188 return rad_put_attr(h, type, str, strlen(str));
1189 }
1190
1191 int
rad_put_message_authentic(struct rad_handle * h)1192 rad_put_message_authentic(struct rad_handle *h)
1193 {
1194 #ifdef WITH_SSL
1195 u_char md_zero[MD5_DIGEST_LENGTH];
1196
1197 if (h->out[POS_CODE] == RAD_ACCOUNTING_REQUEST) {
1198 generr(h, "Message-Authenticator is not valid"
1199 " in accounting requests");
1200 return -1;
1201 }
1202
1203 if (h->authentic_pos == 0) {
1204 h->authentic_pos = h->out_len;
1205 memset(md_zero, 0, sizeof(md_zero));
1206 return (put_raw_attr(h, RAD_MESSAGE_AUTHENTIC, md_zero,
1207 sizeof(md_zero)));
1208 }
1209 return 0;
1210 #else
1211 generr(h, "Message Authenticator not supported,"
1212 " please recompile libradius with SSL support");
1213 return -1;
1214 #endif
1215 }
1216
1217 /*
1218 * Returns the response type code on success, or -1 on failure.
1219 */
1220 int
rad_send_request(struct rad_handle * h)1221 rad_send_request(struct rad_handle *h)
1222 {
1223 struct timeval timelimit;
1224 struct timeval tv;
1225 int fd;
1226 int n;
1227
1228 n = rad_init_send_request(h, &fd, &tv);
1229
1230 if (n != 0)
1231 return n;
1232
1233 gettimeofday(&timelimit, NULL);
1234 timeradd(&tv, &timelimit, &timelimit);
1235
1236 for ( ; ; ) {
1237 fd_set readfds;
1238
1239 FD_ZERO(&readfds);
1240 FD_SET(fd, &readfds);
1241
1242 n = select(fd + 1, &readfds, NULL, NULL, &tv);
1243
1244 if (n == -1) {
1245 generr(h, "select: %s", strerror(errno));
1246 return -1;
1247 }
1248
1249 if (!FD_ISSET(fd, &readfds)) {
1250 /* Compute a new timeout */
1251 gettimeofday(&tv, NULL);
1252 timersub(&timelimit, &tv, &tv);
1253 if (tv.tv_sec > 0 || (tv.tv_sec == 0 && tv.tv_usec > 0))
1254 /* Continue the select */
1255 continue;
1256 }
1257
1258 n = rad_continue_send_request(h, n, &fd, &tv);
1259
1260 if (n != 0)
1261 return n;
1262
1263 gettimeofday(&timelimit, NULL);
1264 timeradd(&tv, &timelimit, &timelimit);
1265 }
1266 }
1267
1268 const char *
rad_strerror(struct rad_handle * h)1269 rad_strerror(struct rad_handle *h)
1270 {
1271 return h->errmsg;
1272 }
1273
1274 /*
1275 * Destructively split a string into fields separated by white space.
1276 * `#' at the beginning of a field begins a comment that extends to the
1277 * end of the string. Fields may be quoted with `"'. Inside quoted
1278 * strings, the backslash escapes `\"' and `\\' are honored.
1279 *
1280 * Pointers to up to the first maxfields fields are stored in the fields
1281 * array. Missing fields get NULL pointers.
1282 *
1283 * The return value is the actual number of fields parsed, and is always
1284 * <= maxfields.
1285 *
1286 * On a syntax error, places a message in the msg string, and returns -1.
1287 */
1288 static int
split(char * str,const char * fields[],int maxfields,char * msg,size_t msglen)1289 split(char *str, const char *fields[], int maxfields, char *msg, size_t msglen)
1290 {
1291 char *p;
1292 int i;
1293 static const char ws[] = " \t";
1294
1295 for (i = 0; i < maxfields; i++)
1296 fields[i] = NULL;
1297 p = str;
1298 i = 0;
1299 while (*p != '\0') {
1300 p += strspn(p, ws);
1301 if (*p == '#' || *p == '\0')
1302 break;
1303 if (i >= maxfields) {
1304 snprintf(msg, msglen, "line has too many fields");
1305 return -1;
1306 }
1307 if (*p == '"') {
1308 char *dst;
1309
1310 dst = ++p;
1311 fields[i] = dst;
1312 while (*p != '"') {
1313 if (*p == '\\') {
1314 p++;
1315 if (*p != '"' && *p != '\\' &&
1316 *p != '\0') {
1317 snprintf(msg, msglen,
1318 "invalid `\\' escape");
1319 return -1;
1320 }
1321 }
1322 if (*p == '\0') {
1323 snprintf(msg, msglen,
1324 "unterminated quoted string");
1325 return -1;
1326 }
1327 *dst++ = *p++;
1328 }
1329 *dst = '\0';
1330 p++;
1331 if (*fields[i] == '\0') {
1332 snprintf(msg, msglen,
1333 "empty quoted string not permitted");
1334 return -1;
1335 }
1336 if (*p != '\0' && strspn(p, ws) == 0) {
1337 snprintf(msg, msglen, "quoted string not"
1338 " followed by white space");
1339 return -1;
1340 }
1341 } else {
1342 fields[i] = p;
1343 p += strcspn(p, ws);
1344 if (*p != '\0')
1345 *p++ = '\0';
1346 }
1347 i++;
1348 }
1349 return i;
1350 }
1351
1352 int
rad_get_vendor_attr(u_int32_t * vendor,const void ** data,size_t * len)1353 rad_get_vendor_attr(u_int32_t *vendor, const void **data, size_t *len)
1354 {
1355 const struct vendor_attribute *attr;
1356
1357 attr = (const struct vendor_attribute *)*data;
1358 *vendor = ntohl(attr->vendor_value);
1359 *data = attr->attrib_data;
1360 *len = attr->attrib_len - 2;
1361
1362 return (attr->attrib_type);
1363 }
1364
1365 int
rad_put_vendor_addr(struct rad_handle * h,int vendor,int type,struct in_addr addr)1366 rad_put_vendor_addr(struct rad_handle *h, int vendor, int type,
1367 struct in_addr addr)
1368 {
1369 return (rad_put_vendor_attr(h, vendor, type, &addr.s_addr,
1370 sizeof addr.s_addr));
1371 }
1372
1373 int
rad_put_vendor_addr6(struct rad_handle * h,int vendor,int type,struct in6_addr addr)1374 rad_put_vendor_addr6(struct rad_handle *h, int vendor, int type,
1375 struct in6_addr addr)
1376 {
1377
1378 return (rad_put_vendor_attr(h, vendor, type, &addr.s6_addr,
1379 sizeof addr.s6_addr));
1380 }
1381
1382 int
rad_put_vendor_attr(struct rad_handle * h,int vendor,int type,const void * value,size_t len)1383 rad_put_vendor_attr(struct rad_handle *h, int vendor, int type,
1384 const void *value, size_t len)
1385 {
1386 struct vendor_attribute *attr;
1387 int res;
1388
1389 if (!h->out_created) {
1390 generr(h, "Please call rad_create_request()"
1391 " before putting attributes");
1392 return -1;
1393 }
1394
1395 if ((attr = malloc(len + 6)) == NULL) {
1396 generr(h, "malloc failure (%zu bytes)", len + 6);
1397 return -1;
1398 }
1399
1400 attr->vendor_value = htonl(vendor);
1401 attr->attrib_type = type;
1402 attr->attrib_len = len + 2;
1403 memcpy(attr->attrib_data, value, len);
1404
1405 res = put_raw_attr(h, RAD_VENDOR_SPECIFIC, attr, len + 6);
1406 free(attr);
1407 if (res == 0 && vendor == RAD_VENDOR_MICROSOFT
1408 && (type == RAD_MICROSOFT_MS_CHAP_RESPONSE
1409 || type == RAD_MICROSOFT_MS_CHAP2_RESPONSE)) {
1410 h->chap_pass = 1;
1411 }
1412 return (res);
1413 }
1414
1415 int
rad_put_vendor_int(struct rad_handle * h,int vendor,int type,u_int32_t i)1416 rad_put_vendor_int(struct rad_handle *h, int vendor, int type, u_int32_t i)
1417 {
1418 u_int32_t value;
1419
1420 value = htonl(i);
1421 return (rad_put_vendor_attr(h, vendor, type, &value, sizeof value));
1422 }
1423
1424 int
rad_put_vendor_string(struct rad_handle * h,int vendor,int type,const char * str)1425 rad_put_vendor_string(struct rad_handle *h, int vendor, int type,
1426 const char *str)
1427 {
1428 return (rad_put_vendor_attr(h, vendor, type, str, strlen(str)));
1429 }
1430
1431 ssize_t
rad_request_authenticator(struct rad_handle * h,char * buf,size_t len)1432 rad_request_authenticator(struct rad_handle *h, char *buf, size_t len)
1433 {
1434 if (len < LEN_AUTH)
1435 return (-1);
1436 memcpy(buf, h->out + POS_AUTH, LEN_AUTH);
1437 if (len > LEN_AUTH)
1438 buf[LEN_AUTH] = '\0';
1439 return (LEN_AUTH);
1440 }
1441
1442 u_char *
rad_demangle(struct rad_handle * h,const void * mangled,size_t mlen)1443 rad_demangle(struct rad_handle *h, const void *mangled, size_t mlen)
1444 {
1445 char R[LEN_AUTH];
1446 const char *S;
1447 int i, Ppos;
1448 MD5_CTX Context;
1449 u_char b[MD5_DIGEST_LENGTH], *demangled;
1450 const u_char *C;
1451
1452 if ((mlen % 16 != 0) || mlen > 128) {
1453 generr(h, "Cannot interpret mangled data of length %lu",
1454 (u_long)mlen);
1455 return NULL;
1456 }
1457
1458 C = mangled;
1459
1460 /* We need the shared secret as Salt */
1461 S = rad_server_secret(h);
1462
1463 /* We need the request authenticator */
1464 if (rad_request_authenticator(h, R, sizeof R) != LEN_AUTH) {
1465 generr(h, "Cannot obtain the RADIUS request authenticator");
1466 return NULL;
1467 }
1468
1469 demangled = malloc(mlen);
1470 if (!demangled)
1471 return NULL;
1472
1473 MD5Init(&Context);
1474 MD5Update(&Context, S, strlen(S));
1475 MD5Update(&Context, R, LEN_AUTH);
1476 MD5Final(b, &Context);
1477 Ppos = 0;
1478 while (mlen) {
1479
1480 mlen -= 16;
1481 for (i = 0; i < 16; i++)
1482 demangled[Ppos++] = C[i] ^ b[i];
1483
1484 if (mlen) {
1485 MD5Init(&Context);
1486 MD5Update(&Context, S, strlen(S));
1487 MD5Update(&Context, C, 16);
1488 MD5Final(b, &Context);
1489 }
1490
1491 C += 16;
1492 }
1493
1494 return demangled;
1495 }
1496
1497 u_char *
rad_demangle_mppe_key(struct rad_handle * h,const void * mangled,size_t mlen,size_t * len)1498 rad_demangle_mppe_key(struct rad_handle *h, const void *mangled,
1499 size_t mlen, size_t *len)
1500 {
1501 char R[LEN_AUTH]; /* variable names as per rfc2548 */
1502 const char *S;
1503 u_char b[MD5_DIGEST_LENGTH], *demangled;
1504 const u_char *A, *C;
1505 MD5_CTX Context;
1506 int Slen, i, Clen, Ppos;
1507 u_char *P;
1508
1509 if (mlen % 16 != SALT_LEN) {
1510 generr(h, "Cannot interpret mangled data of length %lu",
1511 (u_long)mlen);
1512 return NULL;
1513 }
1514
1515 /* We need the RADIUS Request-Authenticator */
1516 if (rad_request_authenticator(h, R, sizeof R) != LEN_AUTH) {
1517 generr(h, "Cannot obtain the RADIUS request authenticator");
1518 return NULL;
1519 }
1520
1521 A = (const u_char *)mangled; /* Salt comes first */
1522 C = (const u_char *)mangled + SALT_LEN; /* Then the ciphertext */
1523 Clen = mlen - SALT_LEN;
1524 S = rad_server_secret(h); /* We need the RADIUS secret */
1525 Slen = strlen(S);
1526 P = alloca(Clen); /* We derive our plaintext */
1527
1528 MD5Init(&Context);
1529 MD5Update(&Context, S, Slen);
1530 MD5Update(&Context, R, LEN_AUTH);
1531 MD5Update(&Context, A, SALT_LEN);
1532 MD5Final(b, &Context);
1533 Ppos = 0;
1534
1535 while (Clen) {
1536 Clen -= 16;
1537
1538 for (i = 0; i < 16; i++)
1539 P[Ppos++] = C[i] ^ b[i];
1540
1541 if (Clen) {
1542 MD5Init(&Context);
1543 MD5Update(&Context, S, Slen);
1544 MD5Update(&Context, C, 16);
1545 MD5Final(b, &Context);
1546 }
1547
1548 C += 16;
1549 }
1550
1551 /*
1552 * The resulting plain text consists of a one-byte length, the text and
1553 * maybe some padding.
1554 */
1555 *len = *P;
1556 if (*len > mlen - 1) {
1557 generr(h, "Mangled data seems to be garbage %zu %zu",
1558 *len, mlen-1);
1559 return NULL;
1560 }
1561
1562 if (*len > MPPE_KEY_LEN * 2) {
1563 generr(h, "Key to long (%zu) for me max. %d",
1564 *len, MPPE_KEY_LEN * 2);
1565 return NULL;
1566 }
1567 demangled = malloc(*len);
1568 if (!demangled)
1569 return NULL;
1570
1571 memcpy(demangled, P + 1, *len);
1572 return demangled;
1573 }
1574
1575 const char *
rad_server_secret(struct rad_handle * h)1576 rad_server_secret(struct rad_handle *h)
1577 {
1578 return (h->servers[h->srv].secret);
1579 }
1580