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