Merge from master
[l2tpns.git] / radius.c
1 // L2TPNS Radius Stuff
2
3 #include <time.h>
4 #include <stdio.h>
5 #include <sys/types.h>
6 #include <sys/socket.h>
7 #include <malloc.h>
8 #include <string.h>
9 #include <fcntl.h>
10 #include <arpa/inet.h>
11 #include <ctype.h>
12 #include <netinet/in.h>
13 #include <errno.h>
14 #include <linux/rtnetlink.h>
15
16 #include "md5.h"
17 #include "constants.h"
18 #include "l2tpns.h"
19 #include "plugin.h"
20 #include "util.h"
21 #include "cluster.h"
22
23 #include "l2tplac.h"
24 #include "pppoe.h"
25
26 extern radiust *radius;
27 extern sessiont *session;
28 extern tunnelt *tunnel;
29 extern configt *config;
30 extern int *radfds;
31 extern ip_filtert *ip_filters;
32
33 static const hasht zero;
34
35 static void calc_auth(const void *buf, size_t len, const uint8_t *in, uint8_t *out)
36 {
37 MD5_CTX ctx;
38
39 MD5_Init(&ctx);
40 MD5_Update(&ctx, (void *)buf, 4); // code, id, length
41 MD5_Update(&ctx, (void *)in, 16); // auth
42 MD5_Update(&ctx, (void *)(buf + 20), len - 20);
43 MD5_Update(&ctx, config->radiussecret, strlen(config->radiussecret));
44 MD5_Final(out, &ctx);
45 }
46
47 // Set up socket for radius requests
48 void initrad(void)
49 {
50 int i;
51 uint16_t port = 0;
52 uint16_t min = config->radius_bind_min;
53 uint16_t max = config->radius_bind_max;
54 int inc = 1;
55 struct sockaddr_in addr;
56
57 if (min)
58 {
59 port = min;
60 if (!max)
61 max = ~0 - 1;
62 }
63 else if (max) /* no minimum specified, bind from max down */
64 {
65 port = max;
66 min = 1;
67 inc = -1;
68 }
69
70 LOG(3, 0, 0, "Creating %d sockets for RADIUS queries\n", RADIUS_FDS);
71 radfds = calloc(sizeof(int), RADIUS_FDS);
72 for (i = 0; i < RADIUS_FDS; i++)
73 {
74 int flags;
75 radfds[i] = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
76 flags = fcntl(radfds[i], F_GETFL, 0);
77 fcntl(radfds[i], F_SETFL, flags | O_NONBLOCK);
78
79 if (port)
80 {
81 int b;
82
83 memset(&addr, 0, sizeof(addr));
84 addr.sin_family = AF_INET;
85 addr.sin_addr.s_addr = INADDR_ANY;
86
87 do {
88 addr.sin_port = htons(port);
89 if ((b = bind(radfds[i], (struct sockaddr *) &addr, sizeof(addr))) < 0)
90 {
91 if ((port += inc) < min || port > max)
92 {
93 LOG(0, 0, 0, "Can't bind RADIUS socket in range %u-%u\n", min, max);
94 exit(1);
95 }
96 }
97 } while (b < 0);
98 }
99 }
100 }
101
102 void radiusclear(uint16_t r, sessionidt s)
103 {
104 if (s) sess_local[s].radius = 0;
105 memset(&radius[r], 0, sizeof(radius[r])); // radius[r].state = RADIUSNULL;
106 }
107
108 static uint16_t get_free_radius()
109 {
110 int count;
111 static uint32_t next_radius_id = 0;
112
113 for (count = MAXRADIUS; count > 0; --count)
114 {
115 ++next_radius_id; // Find the next ID to check.
116 if (next_radius_id >= MAXRADIUS)
117 next_radius_id = 1;
118
119 if (radius[next_radius_id].state == RADIUSNULL)
120 {
121 return next_radius_id;
122 }
123 }
124
125 LOG(0, 0, 0, "Can't find a free radius session! This is very bad!\n");
126 return 0;
127 }
128
129 uint16_t radiusnew(sessionidt s)
130 {
131 uint16_t r = sess_local[s].radius;
132
133 /* re-use */
134 if (r)
135 {
136 LOG(3, s, session[s].tunnel, "Re-used radius %d\n", r);
137 return r;
138 }
139
140 if (!(r = get_free_radius()))
141 {
142 LOG(1, s, session[s].tunnel, "No free RADIUS sessions\n");
143 STAT(radius_overflow);
144 return 0;
145 };
146
147 memset(&radius[r], 0, sizeof(radius[r]));
148 sess_local[s].radius = r;
149 radius[r].session = s;
150 radius[r].state = RADIUSWAIT;
151 radius[r].retry = TIME + 1200; // Wait at least 120 seconds to re-claim this.
152
153 random_data(radius[r].auth, sizeof(radius[r].auth));
154
155 LOG(3, s, session[s].tunnel, "Allocated radius %d\n", r);
156 return r;
157 }
158
159 // Send a RADIUS request
160 void radiussend(uint16_t r, uint8_t state)
161 {
162 struct sockaddr_in addr;
163 uint8_t b[4096]; // RADIUS packet
164 char pass[129];
165 int pl;
166 uint8_t *p;
167 sessionidt s;
168
169 CSTAT(radiussend);
170
171 s = radius[r].session;
172 if (!config->numradiusservers)
173 {
174 LOG(0, s, session[s].tunnel, "No RADIUS servers\n");
175 return;
176 }
177 if (!*config->radiussecret)
178 {
179 LOG(0, s, session[s].tunnel, "No RADIUS secret\n");
180 return;
181 }
182
183 if (state != RADIUSAUTH && state != RADIUSJUSTAUTH && !config->radius_accounting)
184 {
185 // Radius accounting is turned off
186 radiusclear(r, s);
187 return;
188 }
189
190 if (radius[r].state != state)
191 radius[r].try = 0;
192
193 radius[r].state = state;
194 radius[r].retry = backoff(radius[r].try++) + 20; // 3s, 4s, 6s, 10s...
195 LOG(4, s, session[s].tunnel, "Send RADIUS id %d sock %d state %s try %d\n",
196 r >> RADIUS_SHIFT, r & RADIUS_MASK,
197 radius_state(radius[r].state), radius[r].try);
198
199 if (radius[r].try > config->numradiusservers * 2)
200 {
201 if (s)
202 {
203 if (state == RADIUSAUTH || state == RADIUSJUSTAUTH)
204 sessionshutdown(s, "RADIUS timeout.", CDN_ADMIN_DISC, TERM_REAUTHENTICATION_FAILURE);
205 else
206 {
207 LOG(1, s, session[s].tunnel, "RADIUS timeout, but in state %s so don't timeout session\n",
208 radius_state(state));
209 radiusclear(r, s);
210 }
211 STAT(radius_timeout);
212 }
213 else
214 {
215 STAT(radius_retries);
216 radius[r].state = RADIUSWAIT;
217 radius[r].retry = 100;
218 }
219 return;
220 }
221 // contruct RADIUS access request
222 switch (state)
223 {
224 case RADIUSAUTH:
225 case RADIUSJUSTAUTH:
226 b[0] = AccessRequest; // access request
227 break;
228 case RADIUSSTART:
229 case RADIUSSTOP:
230 case RADIUSINTERIM:
231 b[0] = AccountingRequest; // accounting request
232 break;
233 default:
234 LOG(0, 0, 0, "Unknown radius state %d\n", state);
235 }
236 b[1] = r >> RADIUS_SHIFT; // identifier
237 memcpy(b + 4, radius[r].auth, 16);
238
239 p = b + 20;
240 if (s)
241 {
242 *p = 1; // user name
243 p[1] = strlen(session[s].user) + 2;
244 strcpy((char *) p + 2, session[s].user);
245 p += p[1];
246 }
247 if (state == RADIUSAUTH || state == RADIUSJUSTAUTH)
248 {
249 if (radius[r].chap)
250 {
251 *p = 3; // CHAP password
252 p[1] = 19; // length
253 p[2] = radius[r].id; // ID
254 memcpy(p + 3, radius[r].pass, 16); // response from CHAP request
255 p += p[1];
256 *p = 60; // CHAP Challenge
257 p[1] = 18; // length
258 memcpy(p + 2, radius[r].auth, 16);
259 p += p[1];
260 }
261 else
262 {
263 strcpy(pass, radius[r].pass);
264 pl = strlen(pass);
265 while (pl & 15)
266 pass[pl++] = 0; // pad
267 if (pl)
268 { // encrypt
269 hasht hash;
270 int p = 0;
271 while (p < pl)
272 {
273 MD5_CTX ctx;
274 MD5_Init(&ctx);
275 MD5_Update(&ctx, config->radiussecret, strlen(config->radiussecret));
276 if (p)
277 MD5_Update(&ctx, pass + p - 16, 16);
278 else
279 MD5_Update(&ctx, radius[r].auth, 16);
280 MD5_Final(hash, &ctx);
281 do
282 {
283 pass[p] ^= hash[p & 15];
284 p++;
285 }
286 while (p & 15);
287 }
288 }
289 *p = 2; // password
290 p[1] = pl + 2;
291 if (pl)
292 memcpy(p + 2, pass, pl);
293 p += p[1];
294 }
295 }
296 else // accounting
297 {
298 *p = 40; // accounting type
299 p[1] = 6;
300 *(uint32_t *) (p + 2) = htonl(state - RADIUSSTART + 1); // start=1, stop=2, interim=3
301 p += p[1];
302 if (s)
303 {
304 *p = 44; // session ID
305 p[1] = 18;
306 sprintf((char *) p + 2, "%08X%08X", session[s].unique_id, session[s].opened);
307 p += p[1];
308 if (state == RADIUSSTART)
309 { // start
310 *p = 41; // delay
311 p[1] = 6;
312 *(uint32_t *) (p + 2) = htonl(time(NULL) - session[s].opened);
313 p += p[1];
314 sess_local[s].last_interim = time_now; // Setup "first" Interim
315 }
316 else
317 { // stop, interim
318 *p = 42; // input octets
319 p[1] = 6;
320 *(uint32_t *) (p + 2) = htonl(session[s].cin);
321 p += p[1];
322
323 *p = 43; // output octets
324 p[1] = 6;
325 *(uint32_t *) (p + 2) = htonl(session[s].cout);
326 p += p[1];
327
328 *p = 46; // session time
329 p[1] = 6;
330 *(uint32_t *) (p + 2) = htonl(time(NULL) - session[s].opened);
331 p += p[1];
332
333 *p = 47; // input packets
334 p[1] = 6;
335 *(uint32_t *) (p + 2) = htonl(session[s].pin);
336 p += p[1];
337
338 *p = 48; // output packets
339 p[1] = 6;
340 *(uint32_t *) (p + 2) = htonl(session[s].pout);
341 p += p[1];
342
343 *p = 52; // input gigawords
344 p[1] = 6;
345 *(uint32_t *) (p + 2) = htonl(session[s].cin_wrap);
346 p += p[1];
347
348 *p = 53; // output gigawords
349 p[1] = 6;
350 *(uint32_t *) (p + 2) = htonl(session[s].cout_wrap);
351 p += p[1];
352
353 if (state == RADIUSSTOP && radius[r].term_cause)
354 {
355 *p = 49; // acct-terminate-cause
356 p[1] = 6;
357 *(uint32_t *) (p + 2) = htonl(radius[r].term_cause);
358 p += p[1];
359
360 if (radius[r].term_msg)
361 {
362 *p = 26; // vendor-specific
363 *(uint32_t *) (p + 2) = htonl(9); // Cisco
364 p[6] = 1; // Cisco-AVPair
365 p[7] = 2 + sprintf((char *) p + 8, "disc-cause-ext=%s", radius[r].term_msg);
366 p[1] = p[7] + 6;
367 p += p[1];
368 }
369 }
370 }
371
372 if (session[s].classlen) {
373 *p = 25; // class
374 p[1] = session[s].classlen + 2;
375 memcpy(p + 2, session[s].class, session[s].classlen);
376 p += p[1];
377 }
378
379 {
380 struct param_radius_account acct = { &tunnel[session[s].tunnel], &session[s], &p };
381 run_plugins(PLUGIN_RADIUS_ACCOUNT, &acct);
382 }
383 }
384 }
385
386 if (s)
387 {
388 *p = 5; // NAS-Port
389 p[1] = 6;
390 *(uint32_t *) (p + 2) = htonl(s);
391 p += p[1];
392
393 *p = 6; // Service-Type
394 p[1] = 6;
395 *(uint32_t *) (p + 2) = htonl((state == RADIUSJUSTAUTH ? 8 : 2)); // Authenticate only or Framed-User respectevily
396 p += p[1];
397
398 *p = 7; // Framed-Protocol
399 p[1] = htonl((state == RADIUSJUSTAUTH ? 0 : 6));
400 *(uint32_t *) (p + 2) = htonl((state == RADIUSJUSTAUTH ? 0 : 1)); // PPP
401 p += p[1];
402
403 if (session[s].ip)
404 {
405 *p = 8; // Framed-IP-Address
406 p[1] = 6;
407 *(uint32_t *) (p + 2) = htonl(session[s].ip);
408 p += p[1];
409 }
410
411 if (session[s].route[0].ip)
412 {
413 int r;
414 for (r = 0; s && r < MAXROUTE && session[s].route[r].ip; r++)
415 {
416 *p = 22; // Framed-Route
417 p[1] = sprintf((char *) p + 2, "%s/%d %s 1",
418 fmtaddr(htonl(session[s].route[r].ip), 0),
419 session[s].route[r].prefixlen,
420 fmtaddr(htonl(session[s].ip), 1)) + 2;
421
422 p += p[1];
423 }
424 }
425
426 if (session[s].session_timeout)
427 {
428 *p = 27; // Session-Timeout
429 p[1] = 6;
430 *(uint32_t *) (p + 2) = htonl(session[s].session_timeout);
431 p += p[1];
432 }
433
434 if (session[s].idle_timeout)
435 {
436 *p = 28; // Idle-Timeout
437 p[1] = 6;
438 *(uint32_t *) (p + 2) = htonl(session[s].idle_timeout);
439 p += p[1];
440 }
441
442 if (*session[s].called)
443 {
444 *p = 30; // called
445 p[1] = strlen(session[s].called) + 2;
446 strcpy((char *) p + 2, session[s].called);
447 p += p[1];
448 }
449
450 if (*session[s].calling)
451 {
452 *p = 31; // calling
453 p[1] = strlen(session[s].calling) + 2;
454 strcpy((char *) p + 2, session[s].calling);
455 p += p[1];
456 }
457 }
458
459 // NAS-IP-Address
460 *p = 4;
461 p[1] = 6;
462 *(uint32_t *)(p + 2) = config->bind_address;
463 p += p[1];
464
465 // All AVpairs added
466 *(uint16_t *) (b + 2) = htons(p - b);
467 if (state != RADIUSAUTH && state != RADIUSJUSTAUTH)
468 {
469 // Build auth for accounting packet
470 calc_auth(b, p - b, zero, b + 4);
471 memcpy(radius[r].auth, b + 4, 16);
472 }
473 memset(&addr, 0, sizeof(addr));
474 addr.sin_family = AF_INET;
475 *(uint32_t *) & addr.sin_addr = config->radiusserver[(radius[r].try - 1) % config->numradiusservers];
476 {
477 // get radius port
478 uint16_t port = config->radiusport[(radius[r].try - 1) % config->numradiusservers];
479 // assume RADIUS accounting port is the authentication port +1
480 addr.sin_port = htons((state == RADIUSAUTH || state == RADIUSJUSTAUTH) ? port : port+1);
481 }
482
483 LOG_HEX(5, "RADIUS Send", b, (p - b));
484 sendto(radfds[r & RADIUS_MASK], b, p - b, 0, (void *) &addr, sizeof(addr));
485 }
486
487 static void handle_avpair(sessionidt s, uint8_t *avp, int len)
488 {
489 uint8_t *key = avp;
490 uint8_t *value = memchr(avp, '=', len);
491 uint8_t tmp[2048] = "";
492
493 if (value)
494 {
495 *value++ = 0;
496 len -= value - key;
497 }
498 else
499 {
500 value = tmp;
501 len = 0;
502 }
503
504 // strip quotes
505 if (len > 2 && (*value == '"' || *value == '\'') && value[len - 1] == *value)
506 {
507 value++;
508 len--;
509 value[len - 1] = 0;
510 }
511 // copy and null terminate
512 else if (len < sizeof(tmp) - 1)
513 {
514 memcpy(tmp, value, len);
515 tmp[len] = 0;
516 value = tmp;
517 }
518 else
519 return;
520
521 // Run hooks
522 {
523 struct param_radius_response p = { &tunnel[session[s].tunnel], &session[s], (char *) key, (char *) value };
524 run_plugins(PLUGIN_RADIUS_RESPONSE, &p);
525 }
526 }
527
528 // process RADIUS response
529 void processrad(uint8_t *buf, int len, char socket_index)
530 {
531 uint8_t b[MAXETHER];
532 uint16_t r;
533 sessionidt s;
534 tunnelidt t = 0;
535 hasht hash;
536 uint8_t routes = 0;
537 int r_code;
538 int r_id;
539 int OpentunnelReq = 0;
540
541 CSTAT(processrad);
542
543 LOG_HEX(5, "RADIUS Response", buf, len);
544 if (len < 20 || len < ntohs(*(uint16_t *) (buf + 2)))
545 {
546 LOG(1, 0, 0, "Duff RADIUS response length %d\n", len);
547 return ;
548 }
549
550 r_code = buf[0]; // response type
551 r_id = buf[1]; // radius reply indentifier.
552
553 len = ntohs(*(uint16_t *) (buf + 2));
554 r = socket_index | (r_id << RADIUS_SHIFT);
555 s = radius[r].session;
556 LOG(3, s, session[s].tunnel, "Received %s, radius %d response for session %u (%s, id %d)\n",
557 radius_state(radius[r].state), r, s, radius_code(r_code), r_id);
558
559 if (!s && radius[r].state != RADIUSSTOP)
560 {
561 LOG(1, s, session[s].tunnel, " Unexpected RADIUS response\n");
562 return;
563 }
564 if (radius[r].state != RADIUSAUTH && radius[r].state != RADIUSJUSTAUTH && radius[r].state != RADIUSSTART
565 && radius[r].state != RADIUSSTOP && radius[r].state != RADIUSINTERIM)
566 {
567 LOG(1, s, session[s].tunnel, " Unexpected RADIUS response\n");
568 return;
569 }
570 t = session[s].tunnel;
571 calc_auth(buf, len, radius[r].auth, hash);
572 do {
573 if (memcmp(hash, buf + 4, 16))
574 {
575 LOG(0, s, session[s].tunnel, " Incorrect auth on RADIUS response!! (wrong secret in radius config?)\n");
576 return; // Do nothing. On timeout, it will try the next radius server.
577 }
578
579 if (((radius[r].state == RADIUSAUTH ||radius[r].state == RADIUSJUSTAUTH) && r_code != AccessAccept && r_code != AccessReject) ||
580 ((radius[r].state == RADIUSSTART || radius[r].state == RADIUSSTOP || radius[r].state == RADIUSINTERIM) && r_code != AccountingResponse))
581 {
582 LOG(1, s, session[s].tunnel, " Unexpected RADIUS response %s\n", radius_code(r_code));
583 return; // We got something we didn't expect. Let the timeouts take
584 // care off finishing the radius session if that's really correct.
585 }
586
587 if (radius[r].state == RADIUSAUTH || radius[r].state == RADIUSJUSTAUTH)
588 {
589 // run post-auth plugin
590 struct param_post_auth packet = {
591 &tunnel[t],
592 &session[s],
593 session[s].user,
594 (r_code == AccessAccept),
595 radius[r].chap ? PPPCHAP : PPPPAP
596 };
597
598 run_plugins(PLUGIN_POST_AUTH, &packet);
599 r_code = packet.auth_allowed ? AccessAccept : AccessReject;
600
601 #ifndef LAC
602 // process auth response
603 if (radius[r].chap)
604 {
605 // CHAP
606 uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP, 0, 0, 0);
607 if (!p) return; // Abort!
608
609 *p = (r_code == AccessAccept) ? 3 : 4; // ack/nak
610 p[1] = radius[r].id;
611 *(uint16_t *) (p + 2) = ntohs(4); // no message
612 tunnelsend(b, (p - b) + 4, t); // send it
613
614 LOG(3, s, session[s].tunnel, " CHAP User %s authentication %s.\n", session[s].user,
615 (r_code == AccessAccept) ? "allowed" : "denied");
616 }
617 else
618 {
619 // PAP
620 uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP, 0, 0, 0);
621 if (!p) return; // Abort!
622
623 // ack/nak
624 *p = r_code;
625 p[1] = radius[r].id;
626 *(uint16_t *) (p + 2) = ntohs(5);
627 p[4] = 0; // no message
628 tunnelsend(b, (p - b) + 5, t); // send it
629
630 LOG(3, s, session[s].tunnel, " PAP User %s authentication %s.\n", session[s].user,
631 (r_code == AccessAccept) ? "allowed" : "denied");
632 }
633 #endif
634
635 if (r_code == AccessAccept)
636 {
637 // Login successful
638 // Extract IP, routes, etc
639 uint8_t *p = buf + 20;
640 uint8_t *e = buf + len;
641 uint8_t tag;
642 uint8_t strtemp[256];
643 lac_reset_rad_tag_tunnel_ctxt();
644
645 for (; p + 2 <= e && p[1] && p + p[1] <= e; p += p[1])
646 {
647 if (*p == 26 && p[1] >= 7)
648 {
649 // Vendor-Specific Attribute
650 uint32_t vendor = ntohl(*(int *)(p + 2));
651 uint8_t attrib = *(p + 6);
652 int attrib_length = *(p + 7) - 2;
653
654 LOG(4, s, session[s].tunnel, " Radius reply contains Vendor-Specific. Vendor=%u Attrib=%u Length=%d\n", vendor, attrib, attrib_length);
655 if (vendor == 9 && attrib == 1) // Cisco-AVPair
656 {
657 if (attrib_length < 0) continue;
658 LOG(3, s, session[s].tunnel, " Cisco-AVPair value: %.*s\n",
659 attrib_length, p + 8);
660
661 handle_avpair(s, p + 8, attrib_length);
662 continue;
663 }
664 else if (vendor == 529 && attrib >= 135 && attrib <= 136) // Ascend
665 {
666 // handle old-format ascend DNS attributes below
667 p += 6;
668 }
669 else if (vendor == 64520) // Sames
670 {
671 //Sames vendor-specific 64520
672 uint8_t *pvs = p + 6; // pvs set to begin to attribute
673 LOG(3, s, session[s].tunnel, " Sames vendor-specific: %d, Attrib: %d, lenght: %d\n", vendor, attrib, attrib_length);
674 grp_processvendorspecific(s, pvs);
675 continue;
676 }
677 else
678 {
679 LOG(3, s, session[s].tunnel, " Unknown vendor-specific: %d, Attrib: %d\n", vendor, attrib);
680 continue;
681 }
682 }
683
684 if (*p == 8)
685 {
686 // Framed-IP-Address
687 if (p[1] < 6) continue;
688 session[s].ip = ntohl(*(uint32_t *) (p + 2));
689 session[s].ip_pool_index = -1;
690 LOG(3, s, session[s].tunnel, " Radius reply contains IP address %s\n",
691 fmtaddr(htonl(session[s].ip), 0));
692
693 if (session[s].ip == 0xFFFFFFFE)
694 session[s].ip = 0; // assign from pool
695 }
696 else if (*p == 135)
697 {
698 // DNS address
699 if (p[1] < 6) continue;
700 session[s].dns1 = ntohl(*(uint32_t *) (p + 2));
701 LOG(3, s, session[s].tunnel, " Radius reply contains primary DNS address %s\n",
702 fmtaddr(htonl(session[s].dns1), 0));
703 }
704 else if (*p == 136)
705 {
706 // DNS address
707 if (p[1] < 6) continue;
708 session[s].dns2 = ntohl(*(uint32_t *) (p + 2));
709 LOG(3, s, session[s].tunnel, " Radius reply contains secondary DNS address %s\n",
710 fmtaddr(htonl(session[s].dns2), 0));
711 }
712 else if (*p == 22)
713 {
714 // Framed-Route
715 in_addr_t ip = 0;
716 uint8_t u = 0;
717 uint8_t bits = 0;
718 uint8_t *n = p + 2;
719 uint8_t *e = p + p[1];
720 while (n < e && (isdigit(*n) || *n == '.'))
721 {
722 if (*n == '.')
723 {
724 ip = (ip << 8) + u;
725 u = 0;
726 }
727 else
728 u = u * 10 + *n - '0';
729 n++;
730 }
731 ip = (ip << 8) + u;
732 if (*n == '/')
733 {
734 n++;
735 while (n < e && isdigit(*n))
736 bits = bits * 10 + *n++ - '0';
737 }
738 else if ((ip >> 24) < 128)
739 bits = 8;
740 else if ((ip >> 24) < 192)
741 bits = 16;
742 else
743 bits = 24;
744
745 if (routes == MAXROUTE)
746 {
747 LOG(1, s, session[s].tunnel, " Too many routes\n");
748 }
749 else if (ip)
750 {
751 LOG(3, s, session[s].tunnel, " Radius reply contains route for %s/%d\n",
752 fmtaddr(htonl(ip), 0), bits);
753
754 session[s].route[routes].ip = ip;
755 session[s].route[routes].prefixlen = bits;
756 routes++;
757 }
758 }
759 else if (*p == 11)
760 {
761 // Filter-Id
762 char *filter = (char *) p + 2;
763 int l = p[1] - 2;
764 char *suffix;
765 int f;
766 uint8_t *fp = 0;
767
768 LOG(3, s, session[s].tunnel, " Radius reply contains Filter-Id \"%.*s\"\n", l, filter);
769 if ((suffix = memchr(filter, '.', l)))
770 {
771 int b = suffix - filter;
772 if (l - b == 3 && !memcmp("in", suffix+1, 2))
773 fp = &session[s].filter_in;
774 else if (l - b == 4 && !memcmp("out", suffix+1, 3))
775 fp = &session[s].filter_out;
776
777 l = b;
778 }
779
780 if (!fp)
781 {
782 LOG(3, s, session[s].tunnel, " Invalid filter\n");
783 continue;
784 }
785
786 if ((f = find_filter(filter, l)) < 0 || !*ip_filters[f].name)
787 {
788 LOG(3, s, session[s].tunnel, " Unknown filter\n");
789 }
790 else
791 {
792 *fp = f + 1;
793 ip_filters[f].used++;
794 }
795 }
796 else if (*p == 27)
797 {
798 // Session-Timeout
799 if (p[1] < 6) continue;
800 session[s].session_timeout = ntohl(*(uint32_t *)(p + 2));
801 LOG(3, s, session[s].tunnel, " Radius reply contains Session-Timeout = %u\n", session[s].session_timeout);
802 if(!session[s].session_timeout && config->kill_timedout_sessions)
803 sessionshutdown(s, "Session timeout is zero", CDN_ADMIN_DISC, 0);
804 }
805 else if (*p == 28)
806 {
807 // Idle-Timeout
808 if (p[1] < 6) continue;
809 session[s].idle_timeout = ntohl(*(uint32_t *)(p + 2));
810 LOG(3, s, session[s].tunnel, " Radius reply contains Idle-Timeout = %u\n", session[s].idle_timeout);
811 }
812 else if (*p == 99)
813 {
814 // Framed-IPv6-Route
815 struct in6_addr r6;
816 int prefixlen;
817 uint8_t *n = p + 2;
818 uint8_t *e = p + p[1];
819 uint8_t *m = memchr(n, '/', e - p);
820
821 *m++ = 0;
822 inet_pton(AF_INET6, (char *) n, &r6);
823
824 prefixlen = 0;
825 while (m < e && isdigit(*m)) {
826 prefixlen = prefixlen * 10 + *m++ - '0';
827 }
828
829 if (prefixlen)
830 {
831 LOG(3, s, session[s].tunnel,
832 " Radius reply contains route for %s/%d\n",
833 n, prefixlen);
834 session[s].ipv6route = r6;
835 session[s].ipv6prefixlen = prefixlen;
836 }
837 }
838 else if (*p == 25)
839 {
840 // Class
841 if (p[1] < 3) continue;
842 session[s].classlen = p[1] - 2;
843 if (session[s].classlen > MAXCLASS)
844 session[s].classlen = MAXCLASS;
845 memcpy(session[s].class, p + 2, session[s].classlen);
846 }
847 else if (*p == 64)
848 {
849 // Tunnel-Type
850 if (p[1] != 6) continue;
851 tag = p[2];
852 LOG(3, s, session[s].tunnel, " Radius reply Tunnel-Type:%d %d\n",
853 tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
854 // Fill context
855 lac_set_rad_tag_tunnel_type(tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
856 /* Request open tunnel to remote LNS*/
857 OpentunnelReq = 1;
858 }
859 else if (*p == 65)
860 {
861 // Tunnel-Medium-Type
862 if (p[1] < 6) continue;
863 tag = p[2];
864 LOG(3, s, session[s].tunnel, " Radius reply Tunnel-Medium-Type:%d %d\n",
865 tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
866 // Fill context
867 lac_set_rad_tag_tunnel_medium_type(tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
868 }
869 else if (*p == 67)
870 {
871 // Tunnel-Server-Endpoint
872 if (p[1] < 3) continue;
873 tag = p[2];
874 //If the Tag field is greater than 0x1F,
875 // it SHOULD be interpreted as the first byte of the following String field.
876 memset(strtemp, 0, 256);
877 if (tag > 0x1F)
878 {
879 tag = 0;
880 memcpy(strtemp, (p + 2), p[1]-2);
881 }
882 else
883 memcpy(strtemp, (p + 3), p[1]-3);
884
885 LOG(3, s, session[s].tunnel, " Radius reply Tunnel-Server-Endpoint:%d %s\n", tag, strtemp);
886 // Fill context
887 lac_set_rad_tag_tunnel_serv_endpt(tag, (char *) strtemp);
888 }
889 else if (*p == 69)
890 {
891 // Tunnel-Password
892 size_t lentemp;
893
894 if (p[1] < 5) continue;
895 tag = p[2];
896
897 memset(strtemp, 0, 256);
898 lentemp = p[1]-3;
899 memcpy(strtemp, (p + 3), lentemp);
900 if (!rad_tunnel_pwdecode(strtemp, &lentemp, config->radiussecret, radius[r].auth))
901 {
902 LOG_HEX(3, "Error Decode Tunnel-Password, Dump Radius reponse:", p, p[1]);
903 continue;
904 }
905
906 LOG(3, s, session[s].tunnel, " Radius reply Tunnel-Password:%d %s\n", tag, strtemp);
907 if (strlen((char *) strtemp) > 63)
908 {
909 LOG(1, s, session[s].tunnel, "tunnel password is too long (>63)\n");
910 continue;
911 }
912 // Fill context
913 lac_set_rad_tag_tunnel_password(tag, (char *) strtemp);
914 }
915 else if (*p == 82)
916 {
917 // Tunnel-Assignment-Id
918 if (p[1] < 3) continue;
919 tag = p[2];
920 //If the Tag field is greater than 0x1F,
921 // it SHOULD be interpreted as the first byte of the following String field.
922 memset(strtemp, 0, 256);
923 if (tag > 0x1F)
924 {
925 tag = 0;
926 memcpy(strtemp, (p + 2), p[1]-2);
927 }
928 else
929 memcpy(strtemp, (p + 3), p[1]-3);
930
931 LOG(3, s, session[s].tunnel, " Radius reply Tunnel-Assignment-Id:%d %s\n", tag, strtemp);
932 // Fill context
933 lac_set_rad_tag_tunnel_assignment_id(tag, (char *) strtemp);
934 }
935 }
936 }
937 else if (r_code == AccessReject)
938 {
939 LOG(2, s, session[s].tunnel, " Authentication rejected for %s\n", session[s].user);
940 sessionkill(s, "Authentication rejected");
941 break;
942 }
943
944 if ((!config->disable_lac_func) && OpentunnelReq)
945 {
946 char assignment_id[256];
947 // Save radius tag context to conf
948 lac_save_rad_tag_tunnels(s);
949
950 memset(assignment_id, 0, 256);
951 if (!lac_rad_select_assignment_id(s, assignment_id))
952 break; // Error no assignment_id
953
954 LOG(3, s, session[s].tunnel, "Select Tunnel Remote LNS for assignment_id == %s\n", assignment_id);
955
956 if (lac_rad_forwardtoremotelns(s, assignment_id, session[s].user))
957 {
958 int ro;
959 // Sanity check, no local IP to session forwarded
960 session[s].ip = 0;
961 for (ro = 0; r < MAXROUTE && session[s].route[ro].ip; r++)
962 {
963 session[s].route[ro].ip = 0;
964 }
965 break;
966 }
967 }
968
969 // process auth response
970 if (radius[r].chap)
971 {
972 // CHAP
973 uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP, 0, 0, 0);
974 if (!p) return; // Abort!
975
976 *p = (r_code == AccessAccept) ? 3 : 4; // ack/nak
977 p[1] = radius[r].id;
978 *(uint16_t *) (p + 2) = ntohs(4); // no message
979 tunnelsend(b, (p - b) + 4, t); // send it
980
981 LOG(3, s, session[s].tunnel, " CHAP User %s authentication %s.\n", session[s].user,
982 (r_code == AccessAccept) ? "allowed" : "denied");
983 }
984 else
985 {
986 // PAP
987 uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP, 0, 0, 0);
988 if (!p) return; // Abort!
989
990 // ack/nak
991 *p = r_code;
992 p[1] = radius[r].id;
993 *(uint16_t *) (p + 2) = ntohs(5);
994 p[4] = 0; // no message
995 tunnelsend(b, (p - b) + 5, t); // send it
996
997 LOG(3, s, session[s].tunnel, " PAP User %s authentication %s.\n", session[s].user,
998 (r_code == AccessAccept) ? "allowed" : "denied");
999 }
1000
1001 if (!session[s].dns1 && config->default_dns1)
1002 {
1003 session[s].dns1 = ntohl(config->default_dns1);
1004 LOG(3, s, t, " Sending dns1 = %s\n", fmtaddr(config->default_dns1, 0));
1005 }
1006 if (!session[s].dns2 && config->default_dns2)
1007 {
1008 session[s].dns2 = ntohl(config->default_dns2);
1009 LOG(3, s, t, " Sending dns2 = %s\n", fmtaddr(config->default_dns2, 0));
1010 }
1011
1012 // Valid Session, set it up
1013 session[s].unique_id = 0;
1014 sessionsetup(s, t);
1015 }
1016 else
1017 {
1018 // An ack for a stop or start record.
1019 LOG(3, s, t, " RADIUS accounting ack recv in state %s\n", radius_state(radius[r].state));
1020 break;
1021 }
1022 } while (0);
1023
1024 // finished with RADIUS
1025 radiusclear(r, s);
1026 }
1027
1028 // Send a retry for RADIUS/CHAP message
1029 void radiusretry(uint16_t r)
1030 {
1031 sessionidt s = radius[r].session;
1032 tunnelidt t = 0;
1033
1034 CSTAT(radiusretry);
1035
1036 if (s) t = session[s].tunnel;
1037
1038 switch (radius[r].state)
1039 {
1040 case RADIUSCHAP: // sending CHAP down PPP
1041 sendchap(s, t);
1042 break;
1043 case RADIUSAUTH: // sending auth to RADIUS server
1044 case RADIUSJUSTAUTH: // sending auth to RADIUS server
1045 case RADIUSSTART: // sending start accounting to RADIUS server
1046 case RADIUSSTOP: // sending stop accounting to RADIUS server
1047 case RADIUSINTERIM: // sending interim accounting to RADIUS server
1048 radiussend(r, radius[r].state);
1049 break;
1050 default:
1051 case RADIUSNULL: // Not in use
1052 case RADIUSWAIT: // waiting timeout before available, in case delayed reply from RADIUS server
1053 // free up RADIUS task
1054 radiusclear(r, s);
1055 LOG(3, s, session[s].tunnel, "Freeing up radius session %d\n", r);
1056 break;
1057 }
1058 }
1059
1060 extern int daefd;
1061
1062 void processdae(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
1063 {
1064 int i, r_code, r_id, length, attribute_length;
1065 uint8_t *packet, attribute;
1066 hasht hash;
1067 char username[MAXUSER] = "";
1068 in_addr_t nas = 0;
1069 in_addr_t ip = 0;
1070 uint32_t port = 0;
1071 uint32_t error = 0;
1072 sessionidt s = 0;
1073 tunnelidt t;
1074 int fin = -1;
1075 int fout = -1;
1076 uint8_t *avpair[64];
1077 int avpair_len[sizeof(avpair)/sizeof(*avpair)];
1078 int avp = 0;
1079 int auth_only = 0;
1080 uint8_t *p;
1081
1082 LOG(3, 0, 0, "DAE request from %s\n", fmtaddr(addr->sin_addr.s_addr, 0));
1083 LOG_HEX(5, "DAE Request", buf, len);
1084
1085 if (len < 20 || len < ntohs(*(uint16_t *) (buf + 2)))
1086 {
1087 LOG(1, 0, 0, "Duff DAE request length %d\n", len);
1088 return;
1089 }
1090
1091 r_code = buf[0]; // request type
1092 r_id = buf[1]; // radius indentifier.
1093
1094 if (r_code != DisconnectRequest && r_code != CoARequest)
1095 {
1096 LOG(1, 0, 0, "Unrecognised DAE request %s\n", radius_code(r_code));
1097 return;
1098 }
1099
1100 if (!config->cluster_iam_master)
1101 {
1102 master_forward_dae_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1103 return;
1104 }
1105
1106 len = ntohs(*(uint16_t *) (buf + 2));
1107
1108 LOG(3, 0, 0, "Received DAE %s, id %d\n", radius_code(r_code), r_id);
1109
1110 // check authenticator
1111 calc_auth(buf, len, zero, hash);
1112 if (memcmp(hash, buf + 4, 16) != 0)
1113 {
1114 LOG(1, 0, 0, "Incorrect vector in DAE request (wrong secret in radius config?)\n");
1115 return;
1116 }
1117
1118 // unpack attributes
1119 packet = buf + 20;
1120 length = len - 20;
1121
1122 while (length > 0)
1123 {
1124 attribute = *packet++;
1125 attribute_length = *packet++;
1126 if (attribute_length < 2)
1127 break;
1128
1129 length -= attribute_length;
1130 attribute_length -= 2;
1131 switch (attribute)
1132 {
1133 case 1: /* username */
1134 len = attribute_length < MAXUSER ? attribute_length : MAXUSER - 1;
1135 memcpy(username, packet, len);
1136 username[len] = 0;
1137 LOG(4, 0, 0, " Received DAE User-Name: %s\n", username);
1138 break;
1139
1140 case 4: /* nas ip address */
1141 nas = *(uint32_t *) packet; // net order
1142 if (nas != config->bind_address)
1143 error = 403; // NAS identification mismatch
1144
1145 LOG(4, 0, 0, " Received DAE NAS-IP-Address: %s\n", fmtaddr(nas, 0));
1146 break;
1147
1148 case 5: /* nas port */
1149 port = ntohl(*(uint32_t *) packet);
1150 if (port < 1 || port > MAXSESSION)
1151 error = 404;
1152
1153 LOG(4, 0, 0, " Received DAE NAS-Port: %u\n", port);
1154 break;
1155
1156 case 6: /* service type */
1157 {
1158 uint32_t service_type = ntohl(*(uint32_t *) packet);
1159 auth_only = service_type == 8; // Authenticate only
1160
1161 LOG(4, 0, 0, " Received DAE Service-Type: %u\n", service_type);
1162 }
1163 break;
1164
1165 case 8: /* ip address */
1166 ip = *(uint32_t *) packet; // net order
1167 LOG(4, 0, 0, " Received DAE Framed-IP-Address: %s\n", fmtaddr(ip, 0));
1168 break;
1169
1170 case 11: /* filter id */
1171 LOG(4, 0, 0, " Received DAE Filter-Id: %.*s\n", attribute_length, packet);
1172 if (!(p = memchr(packet, '.', attribute_length)))
1173 {
1174 error = 404; // invalid request
1175 break;
1176 }
1177
1178 len = p - packet;
1179 i = find_filter((char *) packet, len);
1180 if (i < 0 || !*ip_filters[i].name)
1181 {
1182 error = 404;
1183 break;
1184 }
1185
1186 if (!memcmp(p, ".in", attribute_length - len))
1187 fin = i + 1;
1188 else if (!memcmp(p, ".out", attribute_length - len))
1189 fout = i + 1;
1190 else
1191 error = 404;
1192
1193 break;
1194
1195 case 26: /* vendor specific */
1196 if (attribute_length >= 6
1197 && ntohl(*(uint32_t *) packet) == 9 // Cisco
1198 && *(packet + 4) == 1 // Cisco-AVPair
1199 && *(packet + 5) >= 2) // length
1200 {
1201 int len = *(packet + 5) - 2;
1202 uint8_t *a = packet + 6;
1203
1204 LOG(4, 0, 0, " Received DAE Cisco-AVPair: %.*s\n", len, a);
1205 if (avp < sizeof(avpair)/sizeof(*avpair) - 1)
1206 {
1207 avpair[avp] = a;
1208 avpair_len[avp++] = len;
1209 }
1210 }
1211 break;
1212 }
1213
1214 packet += attribute_length;
1215 }
1216
1217 if (!error && auth_only)
1218 {
1219 if (fin != -1 || fout != -1 || avp)
1220 error = 401; // unsupported attribute
1221 else
1222 error = 405; // unsupported service
1223 }
1224
1225 if (!error && !(port || ip || *username))
1226 error = 402; // missing attribute
1227
1228 // exact match for SID if given
1229 if (!error && port)
1230 {
1231 s = port;
1232 if (!session[s].opened)
1233 error = 503; // not found
1234 }
1235
1236 if (!error && ip)
1237 {
1238 // find/check session by IP
1239 i = sessionbyip(ip);
1240 if (!i || (s && s != i)) // not found or mismatching port
1241 error = 503;
1242 else
1243 s = i;
1244 }
1245
1246 if (!error && *username)
1247 {
1248 if (s)
1249 {
1250 if (strcmp(session[s].user, username))
1251 error = 503;
1252 }
1253 else if (!(s = sessionbyuser(username)))
1254 error = 503;
1255 }
1256
1257 t = session[s].tunnel;
1258
1259 switch (r_code)
1260 {
1261 case DisconnectRequest: // Packet of Disconnect/Death
1262 if (error)
1263 {
1264 r_code = DisconnectNAK;
1265 break;
1266 }
1267
1268 LOG(3, s, t, " DAE Disconnect %d (%s)\n", s, session[s].user);
1269 r_code = DisconnectACK;
1270
1271 sessionshutdown(s, "Requested by PoD", CDN_ADMIN_DISC, TERM_ADMIN_RESET); // disconnect session
1272 break;
1273
1274 case CoARequest: // Change of Authorization
1275 if (error)
1276 {
1277 r_code = CoANAK;
1278 break;
1279 }
1280
1281 LOG(3, s, t, " DAE Change %d (%s)\n", s, session[s].user);
1282 r_code = CoAACK;
1283
1284 // reset
1285 {
1286 struct param_radius_reset p = { &tunnel[session[s].tunnel], &session[s] };
1287 run_plugins(PLUGIN_RADIUS_RESET, &p);
1288 }
1289
1290 // apply filters
1291 if (fin == -1)
1292 fin = 0;
1293 else
1294 LOG(3, s, t, " Filter in %d (%s)\n", fin, ip_filters[fin - 1].name);
1295
1296 if (fout == -1)
1297 fout = 0;
1298 else
1299 LOG(3, s, t, " Filter out %d (%s)\n", fout, ip_filters[fout - 1].name);
1300
1301 filter_session(s, fin, fout);
1302
1303 // process cisco av-pair(s)
1304 for (i = 0; i < avp; i++)
1305 {
1306 LOG(3, s, t, " Cisco-AVPair: %.*s\n", avpair_len[i], avpair[i]);
1307 handle_avpair(s, avpair[i], avpair_len[i]);
1308 }
1309
1310 cluster_send_session(s);
1311 break;
1312 }
1313
1314 // send response
1315 packet = buf;
1316 *packet++ = r_code;
1317 *packet++ = r_id;
1318 // skip len + auth
1319 packet += 2 + 16;
1320 len = packet - buf;
1321
1322 // add attributes
1323 if (error)
1324 {
1325 // add error cause
1326 *packet++ = 101;
1327 *packet++ = 6;
1328 *(uint32_t *) packet = htonl(error);
1329 len += 6;
1330 }
1331
1332 *((uint16_t *)(buf + 2)) = htons(len);
1333
1334 // make vector
1335 calc_auth(buf, len, hash, buf + 4);
1336
1337 LOG(3, 0, 0, "Sending DAE %s, id=%d\n", radius_code(r_code), r_id);
1338
1339 // send DAE response
1340 if (sendtofrom(daefd, buf, len, MSG_DONTWAIT | MSG_NOSIGNAL, (struct sockaddr *) addr, alen, local) < 0)
1341 LOG(0, 0, 0, "Error sending DAE response packet: %s\n", strerror(errno));
1342 }
1343
1344 // Decrypte the encrypted Tunnel Password.
1345 // Defined in RFC-2868.
1346 // the pl2tpsecret buffer must set to 256 characters.
1347 // return 0 on decoding error else length of decoded l2tpsecret
1348 int rad_tunnel_pwdecode(uint8_t *pl2tpsecret, size_t *pl2tpsecretlen,
1349 const char *radiussecret, const uint8_t * auth)
1350 {
1351 MD5_CTX ctx, oldctx;
1352 hasht hash;
1353 int secretlen;
1354 unsigned i, n, len, decodedlen;
1355
1356 /* 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 6 7
1357 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
1358 | Salt | Salt | String ..........
1359 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+*/
1360
1361 len = *pl2tpsecretlen;
1362
1363 if (len < 2)
1364 {
1365 LOG(1, 0, 0, "tunnel password is too short, We need at least a salt\n");
1366 return 0;
1367 }
1368
1369 if (len <= 3)
1370 {
1371 pl2tpsecret[0] = 0;
1372 *pl2tpsecretlen = 0;
1373 LOG(1, 0, 0, "tunnel passwd is empty !!!\n");
1374 return 0;
1375 }
1376
1377 len -= 2; /* discount the salt */
1378
1379 //Use the secret to setup the decryption
1380 secretlen = strlen(radiussecret);
1381
1382 MD5_Init(&ctx);
1383 MD5_Update(&ctx, (void *) radiussecret, secretlen);
1384 oldctx = ctx; /* save intermediate work */
1385
1386 // Set up the initial key:
1387 // b(1) = MD5(radiussecret + auth + salt)
1388 MD5_Update(&ctx, (void *) auth, 16);
1389 MD5_Update(&ctx, pl2tpsecret, 2);
1390
1391 decodedlen = 0;
1392 for (n = 0; n < len; n += 16)
1393 {
1394 int base = 0;
1395
1396 if (n == 0)
1397 {
1398 MD5_Final(hash, &ctx);
1399
1400 ctx = oldctx;
1401
1402 // the first octet, it's the 'data_len'
1403 // Check is correct
1404 decodedlen = pl2tpsecret[2] ^ hash[0];
1405 if (decodedlen >= len)
1406 {
1407 LOG(1, 0, 0, "tunnel password is too long !!!\n");
1408 return 0;
1409 }
1410
1411 MD5_Update(&ctx, pl2tpsecret + 2, 16);
1412 base = 1;
1413 } else
1414 {
1415 MD5_Final(hash, &ctx);
1416
1417 ctx = oldctx;
1418 MD5_Update(&ctx, pl2tpsecret + n + 2, 16);
1419 }
1420
1421 for (i = base; i < 16; i++)
1422 {
1423 pl2tpsecret[n + i - 1] = pl2tpsecret[n + i + 2] ^ hash[i];
1424 }
1425 }
1426
1427 if (decodedlen > 239) decodedlen = 239;
1428
1429 *pl2tpsecretlen = decodedlen;
1430 pl2tpsecret[decodedlen] = 0;
1431
1432 return decodedlen;
1433 };