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[l2tpns.git] / ppp.c
1 // L2TPNS PPP Stuff
2
3 #include <stdio.h>
4 #include <string.h>
5 #include <unistd.h>
6 #include <errno.h>
7 #include <stdlib.h>
8 #include <netinet/ip6.h>
9 #include "dhcp6.h"
10 #include "l2tpns.h"
11 #include "constants.h"
12 #include "plugin.h"
13 #include "util.h"
14 #include "tbf.h"
15 #include "cluster.h"
16
17 #include "l2tplac.h"
18 #include "pppoe.h"
19
20 extern tunnelt *tunnel;
21 extern bundlet *bundle;
22 extern fragmentationt *frag;
23 extern sessiont *session;
24 extern radiust *radius;
25 extern int tunfd;
26 extern char hostname[];
27 extern uint32_t eth_tx;
28 extern time_t time_now;
29 extern uint64_t time_now_ms;
30 extern configt *config;
31
32 static int add_lcp_auth(uint8_t *b, int size, int authtype);
33 static bundleidt new_bundle(void);
34 static int epdiscmp(epdist, epdist);
35 static void setepdis(epdist *, epdist);
36 static void ipcp_open(sessionidt s, tunnelidt t);
37
38 static int first_session_in_bundle(sessionidt s)
39 {
40 bundleidt i;
41 for (i = 1; i < MAXBUNDLE; i++)
42 if (bundle[i].state != BUNDLEFREE)
43 if (epdiscmp(session[s].epdis,bundle[i].epdis) && !strcmp(session[s].user, bundle[i].user))
44 return 0;
45 return 1;
46 }
47
48 // Process PAP messages
49 void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
50 {
51 char user[MAXUSER];
52 char pass[MAXPASS];
53 uint16_t hl;
54 uint16_t r;
55
56 CSTAT(processpap);
57
58 LOG_HEX(5, "PAP", p, l);
59 if (l < 4)
60 {
61 LOG(1, s, t, "Short PAP %u bytes\n", l);
62 STAT(tunnel_rx_errors);
63 sessionshutdown(s, "Short PAP packet.", CDN_ADMIN_DISC, TERM_USER_ERROR);
64 return;
65 }
66
67 if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
68 {
69 LOG(1, s, t, "Length mismatch PAP %u/%u\n", hl, l);
70 STAT(tunnel_rx_errors);
71 sessionshutdown(s, "PAP length mismatch.", CDN_ADMIN_DISC, TERM_USER_ERROR);
72 return;
73 }
74 l = hl;
75
76 if (*p != 1)
77 {
78 LOG(1, s, t, "Unexpected PAP code %d\n", *p);
79 STAT(tunnel_rx_errors);
80 sessionshutdown(s, "Unexpected PAP code.", CDN_ADMIN_DISC, TERM_USER_ERROR);
81 return;
82 }
83
84 if (session[s].ppp.phase != Authenticate)
85 {
86 LOG(2, s, t, "PAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
87 return;
88 }
89
90 {
91 uint8_t *b = p;
92 b += 4;
93 user[0] = pass[0] = 0;
94 if (*b && *b < sizeof(user))
95 {
96 memcpy(user, b + 1, *b);
97 user[*b] = 0;
98 b += 1 + *b;
99 if (*b && *b < sizeof(pass))
100 {
101 memcpy(pass, b + 1, *b);
102 pass[*b] = 0;
103 }
104 }
105 LOG(3, s, t, "PAP login %s/%s\n", user, pass);
106 }
107
108 if ((!config->disable_lac_func) && lac_conf_forwardtoremotelns(s, user))
109 {
110 // Creating a tunnel/session has been started
111 return;
112 }
113
114 if (session[s].ip || !(r = radiusnew(s)))
115 {
116 // respond now, either no RADIUS available or already authenticated
117 uint8_t b[MAXETHER];
118 uint8_t id = p[1];
119 uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP, 0, 0, 0);
120 if (!p) return;
121
122 if (session[s].ip)
123 *p = 2; // ACK
124 else
125 *p = 3; // cant authorise
126 p[1] = id;
127 *(uint16_t *) (p + 2) = htons(5); // length
128 p[4] = 0; // no message
129 tunnelsend(b, 5 + (p - b), t); // send it
130
131 if (session[s].ip)
132 {
133 LOG(3, s, t, "Already an IP allocated: %s (%d)\n",
134 fmtaddr(htonl(session[s].ip), 0), session[s].ip_pool_index);
135 }
136 else
137 {
138 LOG(1, s, t, "No RADIUS session available to authenticate session...\n");
139 sessionshutdown(s, "No free RADIUS sessions.", CDN_UNAVAILABLE, TERM_SERVICE_UNAVAILABLE);
140 }
141 }
142 else
143 {
144 // Run PRE_AUTH plugins
145 struct param_pre_auth packet = { &tunnel[t], &session[s], strdup(user), strdup(pass), PPPPAP, 1 };
146 run_plugins(PLUGIN_PRE_AUTH, &packet);
147 if (!packet.continue_auth)
148 {
149 LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
150 if (packet.username) free(packet.username);
151 if (packet.password) free(packet.password);
152 return;
153 }
154
155 strncpy(session[s].user, packet.username, sizeof(session[s].user) - 1);
156 strncpy(radius[r].pass, packet.password, sizeof(radius[r].pass) - 1);
157
158 free(packet.username);
159 free(packet.password);
160
161 radius[r].id = p[1];
162 LOG(3, s, t, "Sending login for %s/%s to RADIUS\n", user, pass);
163 if ((session[s].mrru) && (!first_session_in_bundle(s)))
164 radiussend(r, RADIUSJUSTAUTH);
165 else
166 radiussend(r, RADIUSAUTH);
167 }
168 }
169
170 // Process CHAP messages
171 void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
172 {
173 uint16_t r;
174 uint16_t hl;
175
176 CSTAT(processchap);
177
178 LOG_HEX(5, "CHAP", p, l);
179
180 if (l < 4)
181 {
182 LOG(1, s, t, "Short CHAP %u bytes\n", l);
183 STAT(tunnel_rx_errors);
184 sessionshutdown(s, "Short CHAP packet.", CDN_ADMIN_DISC, TERM_USER_ERROR);
185 return;
186 }
187
188 if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
189 {
190 LOG(1, s, t, "Length mismatch CHAP %u/%u\n", hl, l);
191 STAT(tunnel_rx_errors);
192 sessionshutdown(s, "CHAP length mismatch.", CDN_ADMIN_DISC, TERM_USER_ERROR);
193 return;
194 }
195 l = hl;
196
197 if (*p != 2)
198 {
199 LOG(1, s, t, "Unexpected CHAP response code %d\n", *p);
200 STAT(tunnel_rx_errors);
201 sessionshutdown(s, "CHAP length mismatch.", CDN_ADMIN_DISC, TERM_USER_ERROR);
202 return;
203 }
204
205 if (session[s].ppp.phase != Authenticate)
206 {
207 LOG(2, s, t, "CHAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase));
208 return;
209 }
210
211 r = sess_local[s].radius;
212 if (!r)
213 {
214 LOG(3, s, t, "Unexpected CHAP message\n");
215
216 // Some modems (Netgear DM602, possibly others) persist in using CHAP even
217 // after ACKing our ConfigReq for PAP.
218 if (sess_local[s].lcp_authtype == AUTHPAP && config->radius_authtypes & AUTHCHAP)
219 {
220 sess_local[s].lcp_authtype = AUTHCHAP;
221 sendchap(s, t);
222 }
223 return;
224 }
225
226 if (p[1] != radius[r].id)
227 {
228 LOG(1, s, t, "Wrong CHAP response ID %d (should be %d) (%d)\n", p[1], radius[r].id, r);
229 STAT(tunnel_rx_errors);
230 sessionshutdown(s, "Unexpected CHAP response ID.", CDN_ADMIN_DISC, TERM_USER_ERROR);
231 return;
232 }
233
234 if (l < 5 || p[4] != 16)
235 {
236 LOG(1, s, t, "Bad CHAP response length %d\n", l < 5 ? -1 : p[4]);
237 STAT(tunnel_rx_errors);
238 sessionshutdown(s, "Bad CHAP response length.", CDN_ADMIN_DISC, TERM_USER_ERROR);
239 return;
240 }
241
242 l -= 5;
243 p += 5;
244 if (l < 16 || l - 16 >= sizeof(session[s].user))
245 {
246 LOG(1, s, t, "CHAP user too long %d\n", l - 16);
247 STAT(tunnel_rx_errors);
248 sessionshutdown(s, "CHAP username too long.", CDN_ADMIN_DISC, TERM_USER_ERROR);
249 return;
250 }
251
252 // Run PRE_AUTH plugins
253 {
254 struct param_pre_auth packet = { &tunnel[t], &session[s], NULL, NULL, PPPCHAP, 1 };
255
256 packet.password = calloc(17, 1);
257 memcpy(packet.password, p, 16);
258
259 p += 16;
260 l -= 16;
261
262 packet.username = calloc(l + 1, 1);
263 memcpy(packet.username, p, l);
264
265 if ((!config->disable_lac_func) && lac_conf_forwardtoremotelns(s, packet.username))
266 {
267 free(packet.username);
268 free(packet.password);
269 // Creating a tunnel/session has been started
270 return;
271 }
272
273 run_plugins(PLUGIN_PRE_AUTH, &packet);
274 if (!packet.continue_auth)
275 {
276 LOG(3, s, t, "A plugin rejected PRE_AUTH\n");
277 if (packet.username) free(packet.username);
278 if (packet.password) free(packet.password);
279 return;
280 }
281
282 strncpy(session[s].user, packet.username, sizeof(session[s].user) - 1);
283 memcpy(radius[r].pass, packet.password, 16);
284
285 free(packet.username);
286 free(packet.password);
287 }
288
289 radius[r].chap = 1;
290 LOG(3, s, t, "CHAP login %s\n", session[s].user);
291 if ((session[s].mrru) && (!first_session_in_bundle(s)))
292 radiussend(r, RADIUSJUSTAUTH);
293 else
294 radiussend(r, RADIUSAUTH);
295 }
296
297 static void dumplcp(uint8_t *p, int l)
298 {
299 int x = l - 4;
300 uint8_t *o = (p + 4);
301
302 LOG_HEX(5, "PPP LCP Packet", p, l);
303 LOG(4, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_code((int)*p), ntohs( ((uint16_t *) p)[1]) );
304 LOG(4, 0, 0, "Length: %d\n", l);
305 if (*p != ConfigReq && *p != ConfigRej && *p != ConfigAck)
306 return;
307
308 while (x > 2)
309 {
310 int type = o[0];
311 int length = o[1];
312 if (length < 2)
313 {
314 LOG(4, 0, 0, " Option length is %d...\n", length);
315 break;
316 }
317 if (type == 0)
318 {
319 LOG(4, 0, 0, " Option type is 0...\n");
320 x -= length;
321 o += length;
322 continue;
323 }
324 switch (type)
325 {
326 case 1: // Maximum-Receive-Unit
327 if (length == 4)
328 LOG(4, 0, 0, " %s %d\n", ppp_lcp_option(type), ntohs(*(uint16_t *)(o + 2)));
329 else
330 LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
331 break;
332 case 2: // Async-Control-Character-Map
333 if (length == 6)
334 {
335 uint32_t asyncmap = ntohl(*(uint32_t *)(o + 2));
336 LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), asyncmap);
337 }
338 else
339 LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
340 break;
341 case 3: // Authentication-Protocol
342 if (length == 4)
343 {
344 int proto = ntohs(*(uint16_t *)(o + 2));
345 LOG(4, 0, 0, " %s 0x%x (%s)\n", ppp_lcp_option(type), proto,
346 proto == PPPPAP ? "PAP" : "UNSUPPORTED");
347 }
348 else if (length == 5)
349 {
350 int proto = ntohs(*(uint16_t *)(o + 2));
351 int algo = *(o + 4);
352 LOG(4, 0, 0, " %s 0x%x 0x%x (%s)\n", ppp_lcp_option(type), proto, algo,
353 (proto == PPPCHAP && algo == 5) ? "CHAP MD5" : "UNSUPPORTED");
354 }
355 else
356 LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
357 break;
358 case 4: // Quality-Protocol
359 {
360 uint32_t qp = ntohl(*(uint32_t *)(o + 2));
361 LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), qp);
362 }
363 break;
364 case 5: // Magic-Number
365 if (length == 6)
366 {
367 uint32_t magicno = ntohl(*(uint32_t *)(o + 2));
368 LOG(4, 0, 0, " %s %x\n", ppp_lcp_option(type), magicno);
369 }
370 else
371 LOG(4, 0, 0, " %s odd length %d\n", ppp_lcp_option(type), length);
372 break;
373 case 7: // Protocol-Field-Compression
374 case 8: // Address-And-Control-Field-Compression
375 LOG(4, 0, 0, " %s\n", ppp_lcp_option(type));
376 break;
377 default:
378 LOG(2, 0, 0, " Unknown PPP LCP Option type %d\n", type);
379 break;
380 }
381 x -= length;
382 o += length;
383 }
384 }
385
386 void lcp_open(sessionidt s, tunnelidt t)
387 {
388 // transition to Authentication or Network phase:
389 session[s].ppp.phase = sess_local[s].lcp_authtype ? Authenticate : Network;
390
391 LOG(3, s, t, "LCP: Opened, phase %s\n", ppp_phase(session[s].ppp.phase));
392
393 // LCP now Opened
394 change_state(s, lcp, Opened);
395
396 if (session[s].ppp.phase == Authenticate)
397 {
398 if (sess_local[s].lcp_authtype == AUTHCHAP)
399 sendchap(s, t);
400 }
401 else
402 {
403 if(session[s].bundle == 0 || bundle[session[s].bundle].num_of_links == 1)
404 {
405 // This-Layer-Up
406 sendipcp(s, t);
407 change_state(s, ipcp, RequestSent);
408 // move to passive state for IPv6 (if configured), CCP
409 if (config->ipv6_prefix.s6_addr[0])
410 change_state(s, ipv6cp, Stopped);
411 else
412 change_state(s, ipv6cp, Closed);
413
414 change_state(s, ccp, Stopped);
415 }
416 else
417 {
418 sessionidt first_ses = bundle[session[s].bundle].members[0];
419 LOG(3, s, t, "MPPP: Skipping IPCP negotiation for session:%d, first session of bundle is:%d\n",s,first_ses);
420 ipcp_open(s, t);
421 }
422 }
423 }
424
425 void lcp_restart(sessionidt s)
426 {
427 session[s].ppp.phase = Establish;
428 // This-Layer-Down
429 change_state(s, ipcp, Dead);
430 change_state(s, ipv6cp, Dead);
431 change_state(s, ccp, Dead);
432 }
433
434 static uint8_t *ppp_conf_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
435 uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option)
436 {
437 if (!*response || **response != ConfigRej)
438 {
439 queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype, 0, 0, 0);
440 if (!queued)
441 return 0;
442
443 *queued = ConfigRej;
444 queued += 4;
445 }
446
447 if ((queued - buf + option[1]) > blen)
448 {
449 LOG(2, s, session[s].tunnel, "PPP overflow for ConfigRej (proto %u, option %u).\n", mtype, *option);
450 return 0;
451 }
452
453 memcpy(queued, option, option[1]);
454 return queued + option[1];
455 }
456
457 static uint8_t *ppp_conf_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype,
458 uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option,
459 uint8_t *value, size_t vlen)
460 {
461 int *nak_sent;
462 switch (mtype)
463 {
464 case PPPLCP: nak_sent = &sess_local[s].lcp.nak_sent; break;
465 case PPPIPCP: nak_sent = &sess_local[s].ipcp.nak_sent; break;
466 case PPPIPV6CP: nak_sent = &sess_local[s].ipv6cp.nak_sent; break;
467 default: return 0; // ?
468 }
469
470 if (*response && **response != ConfigNak)
471 {
472 if (*nak_sent < config->ppp_max_failure) // reject queued
473 return queued;
474
475 return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
476 }
477
478 if (!*response)
479 {
480 if (*nak_sent >= config->ppp_max_failure)
481 return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option);
482
483 queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype, 0, 0, 0);
484 if (!queued)
485 return 0;
486
487 (*nak_sent)++;
488 *queued = ConfigNak;
489 queued += 4;
490 }
491
492 if ((queued - buf + vlen + 2) > blen)
493 {
494 LOG(2, s, session[s].tunnel, "PPP overflow for ConfigNak (proto %u, option %u).\n", mtype, *option);
495 return 0;
496 }
497
498 *queued++ = *option;
499 *queued++ = vlen + 2;
500 memcpy(queued, value, vlen);
501 return queued + vlen;
502 }
503
504 static void ppp_code_rej(sessionidt s, tunnelidt t, uint16_t proto,
505 char *pname, uint8_t *p, uint16_t l, uint8_t *buf, size_t size)
506 {
507 uint8_t *q;
508 int mru = session[s].mru;
509 if (mru < MINMTU) mru = MINMTU;
510 if (mru > size) mru = size;
511
512 l += 4;
513 if (l > mru) l = mru;
514
515 q = makeppp(buf, size, 0, 0, s, t, proto, 0, 0, 0);
516 if (!q) return;
517
518 *q = CodeRej;
519 *(q + 1) = ++sess_local[s].lcp_ident;
520 *(uint16_t *)(q + 2) = htons(l);
521 memcpy(q + 4, p, l - 4);
522
523 LOG(2, s, t, "Unexpected %s code %s\n", pname, ppp_code(*p));
524 LOG(3, s, t, "%s: send %s\n", pname, ppp_code(*q));
525 if (config->debug > 3) dumplcp(q, l);
526
527 tunnelsend(buf, l + (q - buf), t);
528 }
529
530 // Process LCP messages
531 void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
532 {
533 uint8_t b[MAXETHER];
534 uint8_t *q = NULL;
535 uint16_t hl;
536
537 CSTAT(processlcp);
538
539 LOG_HEX(5, "LCP", p, l);
540 if (l < 4)
541 {
542 LOG(1, s, t, "Short LCP %d bytes\n", l);
543 STAT(tunnel_rx_errors);
544 return ;
545 }
546
547 if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
548 {
549 LOG(1, s, t, "Length mismatch LCP %u/%u\n", hl, l);
550 STAT(tunnel_rx_errors);
551 return ;
552 }
553 l = hl;
554
555 if (session[s].die) // going down...
556 return;
557
558 LOG(((*p == EchoReq || *p == EchoReply) ? 4 : 3), s, t,
559 "LCP: recv %s\n", ppp_code(*p));
560
561 if (config->debug > 3) dumplcp(p, l);
562
563 if (*p == ConfigAck)
564 {
565 int x = l - 4;
566 uint8_t *o = (p + 4);
567 int authtype = 0;
568
569 while (x > 2)
570 {
571 int type = o[0];
572 int length = o[1];
573
574 if (length == 0 || type == 0 || x < length) break;
575 switch (type)
576 {
577 case 3: // Authentication-Protocol
578 {
579 int proto = ntohs(*(uint16_t *)(o + 2));
580 if (proto == PPPPAP)
581 authtype = AUTHPAP;
582 else if (proto == PPPCHAP && *(o + 4) == 5)
583 authtype = AUTHCHAP;
584 }
585
586 break;
587 }
588 x -= length;
589 o += length;
590 }
591
592 if (!session[s].ip && authtype)
593 sess_local[s].lcp_authtype = authtype;
594
595 switch (session[s].ppp.lcp)
596 {
597 case RequestSent:
598 initialise_restart_count(s, lcp);
599 change_state(s, lcp, AckReceived);
600 break;
601
602 case AckReceived:
603 case Opened:
604 LOG(2, s, t, "LCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
605 if (session[s].ppp.lcp == Opened)
606 lcp_restart(s);
607
608 sendlcp(s, t);
609 change_state(s, lcp, RequestSent);
610 break;
611
612 case AckSent:
613 lcp_open(s, t);
614 break;
615
616 default:
617 LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
618 }
619 }
620 else if (*p == ConfigReq)
621 {
622 int x = l - 4;
623 uint8_t *o = (p + 4);
624 uint8_t *response = 0;
625 static uint8_t asyncmap[4] = { 0, 0, 0, 0 }; // all zero
626 static uint8_t authproto[5];
627 int changed = 0;
628
629 while (x > 2)
630 {
631 int type = o[0];
632 int length = o[1];
633
634 if (length == 0 || type == 0 || x < length) break;
635 switch (type)
636 {
637 case 1: // Maximum-Receive-Unit
638 {
639 uint16_t mru = ntohs(*(uint16_t *)(o + 2));
640 if (mru >= MINMTU)
641 {
642 session[s].mru = mru;
643 changed++;
644 break;
645 }
646
647 LOG(3, s, t, " Remote requesting MRU of %u. Rejecting.\n", mru);
648 mru = htons(MRU);
649 q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, (uint8_t *) &mru, sizeof(mru));
650 }
651 break;
652
653 case 2: // Async-Control-Character-Map
654 if (!ntohl(*(uint32_t *)(o + 2))) // all bits zero is OK
655 break;
656
657 LOG(3, s, t, " Remote requesting asyncmap. Rejecting.\n");
658 q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap));
659 break;
660
661 case 3: // Authentication-Protocol
662 {
663 int proto = ntohs(*(uint16_t *)(o + 2));
664 char proto_name[] = "0x0000";
665 int alen;
666
667 if (proto == PPPPAP)
668 {
669 if (config->radius_authtypes & AUTHPAP)
670 {
671 sess_local[s].lcp_authtype = AUTHPAP;
672 break;
673 }
674
675 strcpy(proto_name, "PAP");
676 }
677 else if (proto == PPPCHAP)
678 {
679 if (config->radius_authtypes & AUTHCHAP
680 && *(o + 4) == 5) // MD5
681 {
682 sess_local[s].lcp_authtype = AUTHCHAP;
683 break;
684 }
685
686 strcpy(proto_name, "CHAP");
687 }
688 else
689 sprintf(proto_name, "%#4.4x", proto);
690
691 LOG(3, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name);
692
693 alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authprefer);
694 if (alen < 2) break; // paranoia
695
696 q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
697 if (q && *response == ConfigNak &&
698 config->radius_authtypes != config->radius_authprefer)
699 {
700 // alternate type
701 alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authtypes & ~config->radius_authprefer);
702 if (alen < 2) break;
703 q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
704 }
705
706 break;
707 }
708 break;
709
710 case 4: // Quality-Protocol
711 case 5: // Magic-Number
712 case 7: // Protocol-Field-Compression
713 case 8: // Address-And-Control-Field-Compression
714 break;
715
716 case 17: // Multilink Max-Receive-Reconstructed-Unit
717 {
718 uint16_t mrru = ntohs(*(uint16_t *)(o + 2));
719 session[s].mrru = mrru;
720 changed++;
721 LOG(3, s, t, " Received PPP LCP option MRRU: %d\n",mrru);
722 }
723 break;
724
725 case 18: // Multilink Short Sequence Number Header Format
726 {
727 session[s].mssf = 1;
728 changed++;
729 LOG(3, s, t, " Received PPP LCP option MSSN format\n");
730 }
731 break;
732
733 case 19: // Multilink Endpoint Discriminator
734 {
735 uint8_t epdis_class = o[2];
736 int addr;
737
738 session[s].epdis.addr_class = epdis_class;
739 session[s].epdis.length = length - 3;
740 if (session[s].epdis.length > 20)
741 {
742 LOG(1, s, t, "Error: received EndDis Address Length more than 20: %d\n", session[s].epdis.length);
743 session[s].epdis.length = 20;
744 }
745
746 for (addr = 0; addr < session[s].epdis.length; addr++)
747 session[s].epdis.address[addr] = o[3+addr];
748
749 changed++;
750
751 switch (epdis_class)
752 {
753 case LOCALADDR:
754 LOG(3, s, t, " Received PPP LCP option Multilink EndDis Local Address Class: %d\n",epdis_class);
755 break;
756 case IPADDR:
757 LOG(3, s, t, " Received PPP LCP option Multilink EndDis IP Address Class: %d\n",epdis_class);
758 break;
759 case IEEEMACADDR:
760 LOG(3, s, t, " Received PPP LCP option Multilink EndDis IEEE MAC Address Class: %d\n",epdis_class);
761 break;
762 case PPPMAGIC:
763 LOG(3, s, t, " Received PPP LCP option Multilink EndDis PPP Magic No Class: %d\n",epdis_class);
764 break;
765 case PSNDN:
766 LOG(3, s, t, " Received PPP LCP option Multilink EndDis PSND No Class: %d\n",epdis_class);
767 break;
768 default:
769 LOG(3, s, t, " Received PPP LCP option Multilink EndDis NULL Class %d\n",epdis_class);
770 }
771 }
772 break;
773
774 default: // Reject any unknown options
775 LOG(3, s, t, " Rejecting unknown PPP LCP option %d\n", type);
776 q = ppp_conf_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o);
777 }
778 x -= length;
779 o += length;
780 }
781
782 if (changed)
783 cluster_send_session(s);
784
785 if (response)
786 {
787 l = q - response; // LCP packet length
788 *((uint16_t *) (response + 2)) = htons(l); // update header
789 }
790 else
791 {
792 // Send packet back as ConfigAck
793 response = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
794 if (!response) return;
795 *response = ConfigAck;
796 }
797
798 switch (session[s].ppp.lcp)
799 {
800 case Closed:
801 response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP, 0, 0, 0);
802 if (!response) return;
803 *response = TerminateAck;
804 *((uint16_t *) (response + 2)) = htons(l = 4);
805 break;
806
807 case Stopped:
808 initialise_restart_count(s, lcp);
809 sendlcp(s, t);
810 if (*response == ConfigAck)
811 change_state(s, lcp, AckSent);
812 else
813 change_state(s, lcp, RequestSent);
814
815 break;
816
817 case RequestSent:
818 if (*response == ConfigAck)
819 change_state(s, lcp, AckSent);
820
821 break;
822
823 case AckReceived:
824 if (*response == ConfigAck)
825 lcp_open(s, t);
826
827 break;
828
829 case Opened:
830 lcp_restart(s);
831 sendlcp(s, t);
832 /* fallthrough */
833
834 case AckSent:
835 if (*response == ConfigAck)
836 change_state(s, lcp, AckSent);
837 else
838 change_state(s, lcp, RequestSent);
839
840 break;
841
842 case Closing:
843 sessionshutdown(s, "LCP: ConfigReq in state Closing. This should not happen. Killing session.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
844 break;
845
846 default:
847 LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
848 return;
849 }
850
851 LOG(3, s, t, "LCP: send %s\n", ppp_code(*response));
852 if (config->debug > 3) dumplcp(response, l);
853
854 tunnelsend(b, l + (response - b), t);
855 }
856 else if (*p == ConfigNak || *p == ConfigRej)
857 {
858 int x = l - 4;
859 uint8_t *o = (p + 4);
860 int authtype = -1;
861
862 while (x > 2)
863 {
864 int type = o[0];
865 int length = o[1];
866
867 if (length == 0 || type == 0 || x < length) break;
868 switch (type)
869 {
870 case 1: // Maximum-Receive-Unit
871 if (*p == ConfigNak)
872 {
873 if (length < 4) break;
874 sess_local[s].ppp_mru = ntohs(*(uint16_t *)(o + 2));
875 LOG(3, s, t, " Remote requested MRU of %u\n", sess_local[s].ppp_mru);
876 }
877 else
878 {
879 sess_local[s].ppp_mru = 0;
880 LOG(3, s, t, " Remote rejected MRU negotiation\n");
881 }
882
883 break;
884
885 case 3: // Authentication-Protocol
886 if (authtype > 0)
887 break;
888
889 if (*p == ConfigNak)
890 {
891 int proto;
892
893 if (length < 4) break;
894 proto = ntohs(*(uint16_t *)(o + 2));
895
896 if (proto == PPPPAP)
897 {
898 authtype = config->radius_authtypes & AUTHPAP;
899 LOG(3, s, t, " Remote requested PAP authentication...%sing\n",
900 authtype ? "accept" : "reject");
901 }
902 else if (proto == PPPCHAP && length > 4 && *(o + 4) == 5)
903 {
904 authtype = config->radius_authtypes & AUTHCHAP;
905 LOG(3, s, t, " Remote requested CHAP authentication...%sing\n",
906 authtype ? "accept" : "reject");
907 }
908 else
909 {
910 LOG(3, s, t, " Rejecting unsupported authentication %#4x\n",
911 proto);
912 }
913 }
914 else
915 {
916 LOG(2, s, t, "LCP: remote rejected auth negotiation\n");
917 authtype = 0; // shutdown
918 }
919
920 break;
921
922 case 5: // Magic-Number
923 session[s].magic = 0;
924 if (*p == ConfigNak)
925 {
926 if (length < 6) break;
927 session[s].magic = ntohl(*(uint32_t *)(o + 2));
928 }
929
930 if (session[s].magic)
931 LOG(3, s, t, " Remote requested magic-no %x\n", session[s].magic);
932 else
933 LOG(3, s, t, " Remote rejected magic-no\n");
934
935 cluster_send_session(s);
936 break;
937
938 case 17: // Multilink Max-Receive-Reconstructed-Unit
939 {
940 if (*p == ConfigNak)
941 {
942 sess_local[s].mp_mrru = ntohs(*(uint16_t *)(o + 2));
943 LOG(3, s, t, " Remote requested MRRU of %u\n", sess_local[s].mp_mrru);
944 }
945 else
946 {
947 sess_local[s].mp_mrru = 0;
948 LOG(3, s, t, " Remote rejected MRRU negotiation\n");
949 }
950 }
951 break;
952
953 case 18: // Multilink Short Sequence Number Header Format
954 {
955 if (*p == ConfigNak)
956 {
957 sess_local[s].mp_mssf = 0;
958 LOG(3, s, t, " Remote requested Naked mssf\n");
959 }
960 else
961 {
962 sess_local[s].mp_mssf = 0;
963 LOG(3, s, t, " Remote rejected mssf\n");
964 }
965 }
966 break;
967
968 case 19: // Multilink Endpoint Discriminator
969 {
970 if (*p == ConfigNak)
971 {
972 LOG(2, s, t, " Remote should not configNak Endpoint Dis!\n");
973 }
974 else
975 {
976 sess_local[s].mp_epdis = 0;
977 LOG(3, s, t, " Remote rejected Endpoint Discriminator\n");
978 }
979 }
980 break;
981
982 default:
983 LOG(2, s, t, "LCP: remote sent %s for type %u?\n", ppp_code(*p), type);
984 sessionshutdown(s, "Unable to negotiate LCP.", CDN_ADMIN_DISC, TERM_USER_ERROR);
985 return;
986 }
987 x -= length;
988 o += length;
989 }
990
991 if (!authtype)
992 {
993 sessionshutdown(s, "Unsupported authentication.", CDN_ADMIN_DISC, TERM_USER_ERROR);
994 return;
995 }
996
997 if (authtype > 0)
998 sess_local[s].lcp_authtype = authtype;
999
1000 switch (session[s].ppp.lcp)
1001 {
1002 case Closed:
1003 case Stopped:
1004 {
1005 uint8_t *response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP, 0, 0, 0);
1006 if (!response) return;
1007 *response = TerminateAck;
1008 *((uint16_t *) (response + 2)) = htons(l = 4);
1009
1010 LOG(3, s, t, "LCP: send %s\n", ppp_code(*response));
1011 if (config->debug > 3) dumplcp(response, l);
1012
1013 tunnelsend(b, l + (response - b), t);
1014 }
1015 break;
1016
1017 case RequestSent:
1018 case AckSent:
1019 initialise_restart_count(s, lcp);
1020 sendlcp(s, t);
1021 break;
1022
1023 case AckReceived:
1024 LOG(2, s, t, "LCP: ConfigNak in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
1025 sendlcp(s, t);
1026 break;
1027
1028 case Opened:
1029 lcp_restart(s);
1030 sendlcp(s, t);
1031 break;
1032
1033 default:
1034 LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
1035 return;
1036 }
1037 }
1038 else if (*p == TerminateReq)
1039 {
1040 switch (session[s].ppp.lcp)
1041 {
1042 case Closed:
1043 case Stopped:
1044 case Closing:
1045 case Stopping:
1046 case RequestSent:
1047 case AckReceived:
1048 case AckSent:
1049 break;
1050
1051 case Opened:
1052 lcp_restart(s);
1053 zero_restart_count(s, lcp);
1054 change_state(s, lcp, Closing);
1055 break;
1056
1057 default:
1058 LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
1059 return;
1060 }
1061
1062 *p = TerminateAck; // send ack
1063 q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
1064 if (!q) return;
1065
1066 LOG(3, s, t, "LCP: send %s\n", ppp_code(*q));
1067 if (config->debug > 3) dumplcp(q, l);
1068
1069 tunnelsend(b, l + (q - b), t); // send it
1070 }
1071 else if (*p == ProtocolRej)
1072 {
1073 uint16_t proto = 0;
1074
1075 if (l > 4)
1076 {
1077 proto = *(p+4);
1078 if (l > 5 && !(proto & 1))
1079 {
1080 proto <<= 8;
1081 proto |= *(p+5);
1082 }
1083 }
1084
1085 if (proto == PPPIPV6CP)
1086 {
1087 LOG(3, s, t, "IPv6 rejected\n");
1088 change_state(s, ipv6cp, Closed);
1089 }
1090 else
1091 {
1092 LOG(3, s, t, "LCP protocol reject: 0x%04X\n", proto);
1093 }
1094 }
1095 else if (*p == EchoReq)
1096 {
1097 *p = EchoReply; // reply
1098 *(uint32_t *) (p + 4) = htonl(session[s].magic); // our magic number
1099 q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
1100 if (!q) return;
1101
1102 LOG(4, s, t, "LCP: send %s\n", ppp_code(*q));
1103 if (config->debug > 3) dumplcp(q, l);
1104
1105 tunnelsend(b, l + (q - b), t); // send it
1106
1107 if (session[s].ppp.phase == Network && session[s].ppp.ipv6cp == Opened)
1108 send_ipv6_ra(s, t, NULL); // send a RA
1109 }
1110 else if (*p == EchoReply)
1111 {
1112 // Ignore it, last_packet time is set earlier than this.
1113 }
1114 else if (*p != CodeRej)
1115 {
1116 ppp_code_rej(s, t, PPPLCP, "LCP", p, l, b, sizeof(b));
1117 }
1118 }
1119
1120 int join_bundle(sessionidt s)
1121 {
1122 // Search for a bundle to join
1123 bundleidt i;
1124 bundleidt b;
1125 for (i = 1; i < MAXBUNDLE; i++)
1126 {
1127 if (bundle[i].state != BUNDLEFREE)
1128 {
1129 if (epdiscmp(session[s].epdis,bundle[i].epdis) && !strcmp(session[s].user, bundle[i].user))
1130 {
1131 sessionidt first_ses = bundle[i].members[0];
1132 if (bundle[i].mssf != session[s].mssf)
1133 {
1134 // uniformity of sequence number format must be insured
1135 LOG(3, s, session[s].tunnel, "MPPP: unable to bundle session %d in bundle %d cause of different mssf\n", s, i);
1136 return -1;
1137 }
1138 session[s].bundle = i;
1139 session[s].ip = session[first_ses].ip;
1140 session[s].dns1 = session[first_ses].dns1;
1141 session[s].dns2 = session[first_ses].dns2;
1142 session[s].timeout = session[first_ses].timeout;
1143
1144 if(session[s].epdis.length > 0)
1145 setepdis(&bundle[i].epdis, session[s].epdis);
1146
1147 strcpy(bundle[i].user, session[s].user);
1148 bundle[i].members[bundle[i].num_of_links] = s;
1149 bundle[i].num_of_links++;
1150 LOG(3, s, session[s].tunnel, "MPPP: Bundling additional line in bundle (%d), lines:%d\n",i,bundle[i].num_of_links);
1151 return i;
1152 }
1153 }
1154 }
1155
1156 // No previously created bundle was found for this session, so create a new one
1157 if (!(b = new_bundle())) return 0;
1158
1159 session[s].bundle = b;
1160 bundle[b].mrru = session[s].mrru;
1161 bundle[b].mssf = session[s].mssf;
1162 // FIXME !!! to enable l2tpns reading mssf frames receiver_max_seq, sender_max_seq must be introduce
1163 // now session[s].mssf flag indecates that the receiver wish to receive frames in mssf, so max_seq (i.e. recv_max_seq) = 1<<24
1164 /*
1165 if (bundle[b].mssf)
1166 bundle[b].max_seq = 1 << 12;
1167 else */
1168 bundle[b].max_seq = 1 << 24;
1169 if(session[s].epdis.length > 0)
1170 setepdis(&bundle[b].epdis, session[s].epdis);
1171
1172 strcpy(bundle[b].user, session[s].user);
1173 bundle[b].members[0] = s;
1174 bundle[b].timeout = session[s].timeout;
1175 LOG(3, s, session[s].tunnel, "MPPP: Created a new bundle (%d)\n", b);
1176 return b;
1177 }
1178
1179 static int epdiscmp(epdist ep1, epdist ep2)
1180 {
1181 int ad;
1182 if (ep1.length != ep2.length)
1183 return 0;
1184
1185 if (ep1.addr_class != ep2.addr_class)
1186 return 0;
1187
1188 for (ad = 0; ad < ep1.length; ad++)
1189 if (ep1.address[ad] != ep2.address[ad])
1190 return 0;
1191
1192 return 1;
1193 }
1194
1195 static void setepdis(epdist *ep1, epdist ep2)
1196 {
1197 int ad;
1198 ep1->length = ep2.length;
1199 ep1->addr_class = ep2.addr_class;
1200 for (ad = 0; ad < ep2.length; ad++)
1201 ep1->address[ad] = ep2.address[ad];
1202 }
1203
1204 static bundleidt new_bundle()
1205 {
1206 bundleidt i;
1207 for (i = 1; i < MAXBUNDLE; i++)
1208 {
1209 if (bundle[i].state == BUNDLEFREE)
1210 {
1211 LOG(4, 0, 0, "MPPP: Assigning bundle ID %d\n", i);
1212 bundle[i].num_of_links = 1;
1213 bundle[i].last_check = time_now; // Initialize last_check value
1214 bundle[i].state = BUNDLEOPEN;
1215 bundle[i].current_ses = -1; // This is to enforce the first session 0 to be used at first
1216 memset(&frag[i], 0, sizeof(fragmentationt));
1217 if (i > config->cluster_highest_bundleid)
1218 config->cluster_highest_bundleid = i;
1219 return i;
1220 }
1221 }
1222 LOG(0, 0, 0, "MPPP: Can't find a free bundle! There shouldn't be this many in use!\n");
1223 return 0;
1224 }
1225
1226 static void ipcp_open(sessionidt s, tunnelidt t)
1227 {
1228 LOG(3, s, t, "IPCP: Opened, session is now active\n");
1229
1230 change_state(s, ipcp, Opened);
1231
1232 if (!(session[s].walled_garden || session[s].flags & SESSION_STARTED))
1233 {
1234 uint16_t r = radiusnew(s);
1235 if (r)
1236 {
1237 radiussend(r, RADIUSSTART); // send radius start
1238
1239 // don't send further Start records if IPCP is restarted
1240 session[s].flags |= SESSION_STARTED;
1241 cluster_send_session(s);
1242 }
1243 }
1244
1245 // start IPv6 if configured and still in passive state
1246 if (session[s].ppp.ipv6cp == Stopped)
1247 {
1248 sendipv6cp(s, t);
1249 change_state(s, ipv6cp, RequestSent);
1250 }
1251 }
1252
1253 // Process IPCP messages
1254 void processipcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
1255 {
1256 uint8_t b[MAXETHER];
1257 uint8_t *q = 0;
1258 uint16_t hl;
1259
1260 CSTAT(processipcp);
1261
1262 LOG_HEX(5, "IPCP", p, l);
1263 if (l < 4)
1264 {
1265 LOG(1, s, t, "Short IPCP %d bytes\n", l);
1266 STAT(tunnel_rx_errors);
1267 return ;
1268 }
1269
1270 if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
1271 {
1272 LOG(1, s, t, "Length mismatch IPCP %u/%u\n", hl, l);
1273 STAT(tunnel_rx_errors);
1274 return ;
1275 }
1276 l = hl;
1277
1278 if (session[s].ppp.phase < Network)
1279 {
1280 LOG(2, s, t, "IPCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
1281 return;
1282 }
1283
1284 LOG(3, s, t, "IPCP: recv %s\n", ppp_code(*p));
1285
1286 if (*p == ConfigAck)
1287 {
1288 switch (session[s].ppp.ipcp)
1289 {
1290 case RequestSent:
1291 initialise_restart_count(s, ipcp);
1292 change_state(s, ipcp, AckReceived);
1293 break;
1294
1295 case AckReceived:
1296 case Opened:
1297 LOG(2, s, t, "IPCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ipcp));
1298 sendipcp(s, t);
1299 change_state(s, ipcp, RequestSent);
1300 break;
1301
1302 case AckSent:
1303 ipcp_open(s, t);
1304 break;
1305
1306 default:
1307 LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
1308 }
1309 }
1310 else if (*p == ConfigReq)
1311 {
1312 uint8_t *response = 0;
1313 uint8_t *o = p + 4;
1314 int length = l - 4;
1315 int gotip = 0;
1316 in_addr_t addr;
1317
1318 while (length > 2)
1319 {
1320 if (!o[1] || o[1] > length) return;
1321
1322 switch (*o)
1323 {
1324 case 3: // ip address
1325 gotip++; // seen address
1326 if (o[1] != 6) return;
1327
1328 addr = htonl(session[s].ip);
1329 if (memcmp(o + 2, &addr, (sizeof addr)))
1330 {
1331 uint8_t *oq = q;
1332 q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
1333 if (!q || (q != oq && *response == ConfigRej))
1334 {
1335 sessionshutdown(s, "Can't negotiate IPCP.", CDN_ADMIN_DISC, TERM_USER_ERROR);
1336 return;
1337 }
1338 }
1339
1340 break;
1341
1342 case 129: // primary DNS
1343 if (o[1] != 6) return;
1344
1345 addr = htonl(session[s].dns1);
1346 if (memcmp(o + 2, &addr, (sizeof addr)))
1347 {
1348 q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
1349 if (!q) return;
1350 }
1351
1352 break;
1353
1354 case 131: // secondary DNS
1355 if (o[1] != 6) return;
1356
1357 addr = htonl(session[s].dns2);
1358 if (memcmp(o + 2, &addr, sizeof(addr)))
1359 {
1360 q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr));
1361 if (!q) return;
1362 }
1363
1364 break;
1365
1366 default:
1367 LOG(2, s, t, " Rejecting PPP IPCP Option type %d\n", *o);
1368 q = ppp_conf_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o);
1369 if (!q) return;
1370 }
1371
1372 length -= o[1];
1373 o += o[1];
1374 }
1375
1376 if (response)
1377 {
1378 l = q - response; // IPCP packet length
1379 *((uint16_t *) (response + 2)) = htons(l); // update header
1380 }
1381 else if (gotip)
1382 {
1383 // Send packet back as ConfigAck
1384 response = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP, 0, 0, 0);
1385 if (!response) return;
1386 *response = ConfigAck;
1387 }
1388 else
1389 {
1390 LOG(1, s, t, "No IP in IPCP request\n");
1391 STAT(tunnel_rx_errors);
1392 return;
1393 }
1394
1395 switch (session[s].ppp.ipcp)
1396 {
1397 case Closed:
1398 response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPCP, 0, 0, 0);
1399 if (!response) return;
1400 *response = TerminateAck;
1401 *((uint16_t *) (response + 2)) = htons(l = 4);
1402 break;
1403
1404 case Stopped:
1405 initialise_restart_count(s, ipcp);
1406 sendipcp(s, t);
1407 if (*response == ConfigAck)
1408 change_state(s, ipcp, AckSent);
1409 else
1410 change_state(s, ipcp, RequestSent);
1411
1412 break;
1413
1414 case RequestSent:
1415 if (*response == ConfigAck)
1416 change_state(s, ipcp, AckSent);
1417
1418 break;
1419
1420 case AckReceived:
1421 if (*response == ConfigAck)
1422 ipcp_open(s, t);
1423
1424 break;
1425
1426 case Opened:
1427 initialise_restart_count(s, ipcp);
1428 sendipcp(s, t);
1429 /* fallthrough */
1430
1431 case AckSent:
1432 if (*response == ConfigAck)
1433 change_state(s, ipcp, AckSent);
1434 else
1435 change_state(s, ipcp, RequestSent);
1436
1437 break;
1438
1439 default:
1440 LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
1441 return;
1442 }
1443
1444 LOG(3, s, t, "IPCP: send %s\n", ppp_code(*response));
1445 tunnelsend(b, l + (response - b), t);
1446 }
1447 else if (*p == TerminateReq)
1448 {
1449 switch (session[s].ppp.ipcp)
1450 {
1451 case Closed:
1452 case Stopped:
1453 case Closing:
1454 case Stopping:
1455 case RequestSent:
1456 case AckReceived:
1457 case AckSent:
1458 break;
1459
1460 case Opened:
1461 zero_restart_count(s, ipcp);
1462 change_state(s, ipcp, Closing);
1463 break;
1464
1465 default:
1466 LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
1467 return;
1468 }
1469
1470 *p = TerminateAck; // send ack
1471 q = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP, 0, 0, 0);
1472 if (!q) return;
1473
1474 LOG(3, s, t, "IPCP: send %s\n", ppp_code(*q));
1475 tunnelsend(b, l + (q - b), t); // send it
1476 }
1477 else if (*p != CodeRej)
1478 {
1479 ppp_code_rej(s, t, PPPIPCP, "IPCP", p, l, b, sizeof(b));
1480 }
1481 }
1482
1483 static void ipv6cp_open(sessionidt s, tunnelidt t)
1484 {
1485 int i;
1486 LOG(3, s, t, "IPV6CP: Opened\n");
1487
1488 change_state(s, ipv6cp, Opened);
1489 for (i = 0; i < MAXROUTE6 && session[s].route6[i].ipv6prefixlen; i++)
1490 {
1491 route6set(s, session[s].route6[i].ipv6route, session[s].route6[i].ipv6prefixlen, 1);
1492 }
1493
1494 if (session[s].ipv6address.s6_addr[0])
1495 {
1496 // Check if included in prefix
1497 if (sessionbyipv6(session[s].ipv6address) != s)
1498 route6set(s, session[s].ipv6address, 128, 1);
1499 }
1500
1501 // Send an initial RA (TODO: Should we send these regularly?)
1502 send_ipv6_ra(s, t, NULL);
1503 }
1504
1505 // Process IPV6CP messages
1506 void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
1507 {
1508 uint8_t b[MAXETHER];
1509 uint8_t *q = 0;
1510 uint16_t hl;
1511
1512 CSTAT(processipv6cp);
1513
1514 LOG_HEX(5, "IPV6CP", p, l);
1515 if (l < 4)
1516 {
1517 LOG(1, s, t, "Short IPV6CP %d bytes\n", l);
1518 STAT(tunnel_rx_errors);
1519 return ;
1520 }
1521
1522 if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
1523 {
1524 LOG(1, s, t, "Length mismatch IPV6CP %u/%u\n", hl, l);
1525 STAT(tunnel_rx_errors);
1526 return ;
1527 }
1528 l = hl;
1529
1530 if (session[s].ppp.phase < Network)
1531 {
1532 LOG(2, s, t, "IPV6CP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
1533 return;
1534 }
1535
1536 LOG(3, s, t, "IPV6CP: recv %s\n", ppp_code(*p));
1537
1538 if (!session[s].ip)
1539 {
1540 LOG(3, s, t, "IPV6CP: no IPv4 address (IPCP in state %s)\n", ppp_state(session[s].ppp.ipcp));
1541 return; // need IPCP to complete...
1542 }
1543
1544 if (*p == ConfigAck)
1545 {
1546 switch (session[s].ppp.ipv6cp)
1547 {
1548 case RequestSent:
1549 initialise_restart_count(s, ipv6cp);
1550 change_state(s, ipv6cp, AckReceived);
1551 break;
1552
1553 case AckReceived:
1554 case Opened:
1555 LOG(2, s, t, "IPV6CP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ipv6cp));
1556 sendipv6cp(s, t);
1557 change_state(s, ipv6cp, RequestSent);
1558 break;
1559
1560 case AckSent:
1561 ipv6cp_open(s, t);
1562 break;
1563
1564 default:
1565 LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
1566 }
1567 }
1568 else if (*p == ConfigReq)
1569 {
1570 uint8_t *response = 0;
1571 uint8_t *o = p + 4;
1572 int length = l - 4;
1573 int gotip = 0;
1574 uint32_t ident[2];
1575
1576 while (length > 2)
1577 {
1578 if (!o[1] || o[1] > length) return;
1579
1580 switch (*o)
1581 {
1582 case 1: // interface identifier
1583 gotip++; // seen address
1584 if (o[1] != 10) return;
1585
1586 if (session[s].ipv6address.s6_addr[0])
1587 {
1588 // LSB 64bits of assigned IPv6 address to user (see radius attribut Framed-IPv6-Address)
1589 memcpy(&ident[0], &session[s].ipv6address.s6_addr[8], 8);
1590 }
1591 else
1592 {
1593 ident[0] = htonl(session[s].ip);
1594 ident[1] = 0;
1595 }
1596
1597 if (memcmp(o + 2, ident, sizeof(ident)))
1598 {
1599 q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, (uint8_t *)ident, sizeof(ident));
1600 if (!q) return;
1601 }
1602
1603 break;
1604
1605 default:
1606 LOG(2, s, t, " Rejecting PPP IPV6CP Option type %d\n", *o);
1607 q = ppp_conf_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o);
1608 if (!q) return;
1609 }
1610
1611 length -= o[1];
1612 o += o[1];
1613 }
1614
1615 if (response)
1616 {
1617 l = q - response; // IPV6CP packet length
1618 *((uint16_t *) (response + 2)) = htons(l); // update header
1619 }
1620 else if (gotip)
1621 {
1622 // Send packet back as ConfigAck
1623 response = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP, 0, 0, 0);
1624 if (!response) return;
1625 *response = ConfigAck;
1626 }
1627 else
1628 {
1629 LOG(1, s, t, "No interface identifier in IPV6CP request\n");
1630 STAT(tunnel_rx_errors);
1631 return;
1632 }
1633
1634 switch (session[s].ppp.ipv6cp)
1635 {
1636 case Closed:
1637 response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPV6CP, 0, 0, 0);
1638 if (!response) return;
1639 *response = TerminateAck;
1640 *((uint16_t *) (response + 2)) = htons(l = 4);
1641 break;
1642
1643 case Stopped:
1644 initialise_restart_count(s, ipv6cp);
1645 sendipv6cp(s, t);
1646 if (*response == ConfigAck)
1647 change_state(s, ipv6cp, AckSent);
1648 else
1649 change_state(s, ipv6cp, RequestSent);
1650
1651 break;
1652
1653 case RequestSent:
1654 if (*response == ConfigAck)
1655 change_state(s, ipv6cp, AckSent);
1656
1657 break;
1658
1659 case AckReceived:
1660 if (*response == ConfigAck)
1661 ipv6cp_open(s, t);
1662
1663 break;
1664
1665 case Opened:
1666 initialise_restart_count(s, ipv6cp);
1667 sendipv6cp(s, t);
1668 /* fallthrough */
1669
1670 case AckSent:
1671 if (*response == ConfigAck)
1672 change_state(s, ipv6cp, AckSent);
1673 else
1674 change_state(s, ipv6cp, RequestSent);
1675
1676 break;
1677
1678 default:
1679 LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
1680 return;
1681 }
1682
1683 LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*response));
1684 tunnelsend(b, l + (response - b), t);
1685 }
1686 else if (*p == TerminateReq)
1687 {
1688 switch (session[s].ppp.ipv6cp)
1689 {
1690 case Closed:
1691 case Stopped:
1692 case Closing:
1693 case Stopping:
1694 case RequestSent:
1695 case AckReceived:
1696 case AckSent:
1697 break;
1698
1699 case Opened:
1700 zero_restart_count(s, ipv6cp);
1701 change_state(s, ipv6cp, Closing);
1702 break;
1703
1704 default:
1705 LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
1706 return;
1707 }
1708
1709 *p = TerminateAck; // send ack
1710 q = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP, 0, 0, 0);
1711 if (!q) return;
1712
1713 LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*q));
1714 tunnelsend(b, l + (q - b), t); // send it
1715 }
1716 else if (*p != CodeRej)
1717 {
1718 ppp_code_rej(s, t, PPPIPV6CP, "IPV6CP", p, l, b, sizeof(b));
1719 }
1720 }
1721
1722 static void update_sessions_in_stat(sessionidt s, uint16_t l)
1723 {
1724 bundleidt b = session[s].bundle;
1725 if (!b)
1726 {
1727 increment_counter(&session[s].cin, &session[s].cin_wrap, l);
1728 session[s].cin_delta += l;
1729 session[s].pin++;
1730
1731 sess_local[s].cin += l;
1732 sess_local[s].pin++;
1733 }
1734 else
1735 {
1736 int i = frag[b].re_frame_begin_index;
1737 int end = frag[b].re_frame_end_index;
1738 for (;;)
1739 {
1740 l = frag[b].fragment[i].length;
1741 s = frag[b].fragment[i].sid;
1742 increment_counter(&session[s].cin, &session[s].cin_wrap, l);
1743 session[s].cin_delta += l;
1744 session[s].pin++;
1745
1746 sess_local[s].cin += l;
1747 sess_local[s].pin++;
1748 if (i == end)
1749 return;
1750 i = (i + 1) & MAXFRAGNUM_MASK;
1751 }
1752 }
1753 }
1754
1755 // process IP packet received
1756 //
1757 // This MUST be called with at least 4 byte behind 'p'.
1758 // (i.e. this routine writes to p[-4]).
1759 void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
1760 {
1761 in_addr_t ip, ip_dst;
1762
1763 CSTAT(processipin);
1764
1765 LOG_HEX(5, "IP", p, l);
1766
1767 if (l < 20)
1768 {
1769 LOG(1, s, t, "IP packet too short %d\n", l);
1770 STAT(tunnel_rx_errors);
1771 return ;
1772 }
1773
1774 ip = ntohl(*(uint32_t *)(p + 12));
1775 ip_dst = *(uint32_t *)(p + 16);
1776
1777 if (l > MAXETHER)
1778 {
1779 LOG(1, s, t, "IP packet too long %d\n", l);
1780 STAT(tunnel_rx_errors);
1781 return ;
1782 }
1783
1784 if (session[s].ppp.phase != Network || session[s].ppp.ipcp != Opened)
1785 return;
1786
1787 if (!session[s].bundle || bundle[session[s].bundle].num_of_links < 2) // FIXME:
1788 {
1789 // no spoof (do sessionbyip to handled statically routed subnets)
1790 if (!config->disable_no_spoof && ip != session[s].ip && sessionbyip(htonl(ip)) != s)
1791 {
1792 LOG(4, s, t, "Dropping packet with spoofed IP %s\n", fmtaddr(htonl(ip), 0));
1793 return;
1794 }
1795 }
1796
1797 // run access-list if any
1798 if (session[s].filter_in && !ip_filter(p, l, session[s].filter_in - 1))
1799 return;
1800
1801 // adjust MSS on SYN and SYN,ACK packets with options
1802 if ((ntohs(*(uint16_t *) (p + 6)) & 0x1fff) == 0 && p[9] == IPPROTO_TCP) // first tcp fragment
1803 {
1804 int ihl = (p[0] & 0xf) * 4; // length of IP header
1805 if (l >= ihl + 20 && (p[ihl + 13] & TCP_FLAG_SYN) && ((p[ihl + 12] >> 4) > 5))
1806 adjust_tcp_mss(s, t, p, l, p + ihl);
1807 }
1808
1809 // Add on the tun header
1810 p -= 4;
1811 *(uint32_t *) p = htonl(PKTIP);
1812 l += 4;
1813
1814 if (session[s].tbf_in)
1815 {
1816 if (!config->no_throttle_local_IP || !sessionbyip(ip_dst))
1817 {
1818 // Are we throttling this session?
1819 if (config->cluster_iam_master)
1820 tbf_queue_packet(session[s].tbf_in, p, l);
1821 else
1822 master_throttle_packet(session[s].tbf_in, p, l);
1823 return;
1824 }
1825 }
1826
1827 // send to ethernet
1828 if (tun_write(p, l) < 0)
1829 {
1830 STAT(tun_tx_errors);
1831 LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
1832 l, strerror(errno), tunfd, p);
1833
1834 return;
1835 }
1836
1837 p += 4;
1838 l -= 4;
1839
1840 if (session[s].snoop_ip && session[s].snoop_port)
1841 {
1842 // Snooping this session
1843 snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
1844 }
1845
1846 update_sessions_in_stat(s, l);
1847
1848 eth_tx += l;
1849
1850 STAT(tun_tx_packets);
1851 INC_STAT(tun_tx_bytes, l);
1852 }
1853
1854 // process Multilink PPP packet received
1855 void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
1856 {
1857 bundleidt b = session[s].bundle;
1858 bundlet * this_bundle = &bundle[b];
1859 uint32_t maskSeq, max_seq;
1860 int frag_offset;
1861 uint16_t frag_index, frag_index_next, frag_index_prev;
1862 fragmentationt *this_fragmentation = &frag[b];
1863 uint8_t begin_frame = (*p & MP_BEGIN);
1864 uint8_t end_frame = (*p & MP_END);
1865 uint32_t seq_num, seq_num_next, seq_num_prev;
1866 uint32_t i;
1867 uint8_t flags = *p;
1868 uint16_t begin_index, end_index;
1869
1870 // Perform length checking
1871 if(l > MAXFRAGLEN)
1872 {
1873 LOG(2, s, t, "MPPP: discarding fragment larger than MAXFRAGLEN\n");
1874 return;
1875 }
1876
1877 if(!b)
1878 {
1879 LOG(2, s, t, "MPPP: Invalid bundle id: 0\n");
1880 return;
1881 }
1882 // FIXME !! session[s].mssf means that the receiver wants to receive frames in mssf not means the receiver will send frames in mssf
1883 /* if(session[s].mssf)
1884 {
1885 // Get 12 bit for seq number
1886 seq_num = ntohs((*(uint16_t *) p) & 0xFF0F);
1887 p += 2;
1888 l -= 2;
1889 // After this point the pointer should be advanced 2 bytes
1890 LOG(3, s, t, "MPPP: 12 bits, sequence number: %d\n",seq_num);
1891 }
1892 else */
1893 {
1894 // Get 24 bit for seq number
1895 seq_num = ntohl((*(uint32_t *) p) & 0xFFFFFF00);
1896 p += 4;
1897 l -= 4;
1898 // After this point the pointer should be advanced 4 bytes
1899 LOG(4, s, t, "MPPP: 24 bits sequence number:%d\n",seq_num);
1900 }
1901
1902 max_seq = this_bundle->max_seq;
1903 maskSeq = max_seq - 1;
1904
1905 /*
1906 * Expand sequence number to 32 bits, making it as close
1907 * as possible to this_fragmentation->M.
1908 */
1909 seq_num |= this_fragmentation->M & ~maskSeq;
1910 if ((int)(this_fragmentation->M - seq_num) > (int)(maskSeq >> 1))
1911 {
1912 seq_num += maskSeq + 1;
1913 }
1914 else if ((int)(seq_num - this_fragmentation->M) > (int)(maskSeq >> 1))
1915 {
1916 seq_num -= maskSeq + 1; /* should never happen */
1917 }
1918
1919 // calculate this fragment's offset from the begin seq in the bundle
1920 frag_offset = (int) (seq_num - this_fragmentation->start_seq);
1921
1922 sess_local[s].last_seq = seq_num;
1923
1924 // calculate the jitter average
1925 uint32_t ljitter = time_now_ms - sess_local[s].prev_time;
1926 if (ljitter > 0)
1927 {
1928 sess_local[s].jitteravg = (sess_local[s].jitteravg + ljitter)>>1;
1929 sess_local[s].prev_time = time_now_ms;
1930 }
1931
1932 uint32_t Mmin;
1933
1934 if (seq_num < this_fragmentation->M)
1935 {
1936 Mmin = seq_num;
1937 this_fragmentation->M = seq_num;
1938 }
1939 else
1940 {
1941 Mmin = sess_local[(this_bundle->members[0])].last_seq;
1942 for (i = 1; i < this_bundle->num_of_links; i++)
1943 {
1944 uint32_t s_seq = sess_local[(this_bundle->members[i])].last_seq;
1945 if (s_seq < Mmin)
1946 Mmin = s_seq;
1947 }
1948 this_fragmentation->M = Mmin;
1949 }
1950
1951 // calculate M offset of the M seq in the bundle
1952 int M_offset = (int) (Mmin - this_fragmentation->start_seq);
1953
1954 if (M_offset >= MAXFRAGNUM)
1955 {
1956 // There have a long break of the link !!!!!!!!
1957 // M_offset is bigger that the fragmentation buffer size
1958 LOG(3, s, t, "MPPP: M_offset out of range, min:%d, begin_seq:%d\n", Mmin, this_fragmentation->start_seq);
1959
1960 // Calculate the new start index, the previous frag are lost
1961 begin_index = (M_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK;
1962
1963 // Set new Start sequence
1964 this_fragmentation->start_index = begin_index;
1965 this_fragmentation->start_seq = Mmin;
1966 M_offset = 0;
1967 // recalculate the fragment offset from the new begin seq in the bundle
1968 frag_offset = (int) (seq_num - Mmin);
1969 }
1970
1971 // discard this fragment if the packet comes before the start sequence
1972 if (frag_offset < 0)
1973 {
1974 // this packet comes before the next
1975 LOG(3, s, t, "MPPP: (COMES BEFORE) the next, seq:%d, begin_seq:%d, size_frag:%d, flags:%02X is LOST\n", seq_num, this_fragmentation->start_seq, l, flags);
1976 return;
1977 }
1978
1979 // discard if frag_offset is bigger that the fragmentation buffer size
1980 if (frag_offset >= MAXFRAGNUM)
1981 {
1982 // frag_offset is bigger that the fragmentation buffer size
1983 LOG(3, s, t, "MPPP: Index out of range, seq:%d, begin_seq:%d\n", seq_num, this_fragmentation->start_seq);
1984 return;
1985 }
1986
1987 //caculate received fragment's index in the fragment array
1988 frag_index = (frag_offset + this_fragmentation->start_index) & MAXFRAGNUM_MASK;
1989
1990 // insert the frame in it's place
1991 fragmentt *this_frag = &this_fragmentation->fragment[frag_index];
1992
1993 if (this_frag->length > 0)
1994 // This fragment is lost, It was around the buffer and it was never completed the packet.
1995 LOG(3, this_frag->sid, this_frag->tid, "MPPP: (INSERT) seq_num:%d frag_index:%d flags:%02X is LOST\n",
1996 this_frag->seq, frag_index, this_frag->flags);
1997
1998 this_frag->length = l;
1999 this_frag->sid = s;
2000 this_frag->tid = t;
2001 this_frag->flags = flags;
2002 this_frag->seq = seq_num;
2003 this_frag->jitteravg = sess_local[s].jitteravg;
2004 memcpy(this_frag->data, p, l);
2005
2006 LOG(4, s, t, "MPPP: seq_num:%d frag_index:%d INSERTED flags: %02X\n", seq_num, frag_index, flags);
2007
2008 //next frag index
2009 frag_index_next = (frag_index + 1) & MAXFRAGNUM_MASK;
2010 //previous frag index
2011 frag_index_prev = (frag_index - 1) & MAXFRAGNUM_MASK;
2012 // next seq
2013 seq_num_next = seq_num + 1;
2014 // previous seq
2015 seq_num_prev = seq_num - 1;
2016
2017 // Clean the buffer and log the lost fragments
2018 if ((frag_index_next != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_next].length)
2019 {
2020 // check if the next frag is a lost fragment
2021 if (this_fragmentation->fragment[frag_index_next].seq != seq_num_next)
2022 {
2023 // This fragment is lost, It was around the buffer and it was never completed the packet.
2024 LOG(3, this_fragmentation->fragment[frag_index_next].sid, this_fragmentation->fragment[frag_index_next].tid,
2025 "MPPP: (NEXT) seq_num:%d frag_index:%d flags:%02X is LOST\n",
2026 this_fragmentation->fragment[frag_index_next].seq, frag_index_next,
2027 this_fragmentation->fragment[frag_index_next].flags);
2028 // this frag is lost
2029 this_fragmentation->fragment[frag_index_next].length = 0;
2030 this_fragmentation->fragment[frag_index_next].flags = 0;
2031
2032 if (begin_frame && (!end_frame)) return; // assembling frame failed
2033 }
2034 }
2035
2036 // Clean the buffer and log the lost fragments
2037 if ((frag_index != this_fragmentation->start_index) && this_fragmentation->fragment[frag_index_prev].length)
2038 {
2039 // check if the next frag is a lost fragment
2040 if (this_fragmentation->fragment[frag_index_prev].seq != seq_num_prev)
2041 {
2042 // This fragment is lost, It was around the buffer and it was never completed the packet.
2043 LOG(3, this_fragmentation->fragment[frag_index_prev].sid, this_fragmentation->fragment[frag_index_prev].tid,
2044 "MPPP: (PREV) seq_num:%d frag_index:%d flags:%02X is LOST\n",
2045 this_fragmentation->fragment[frag_index_prev].seq, frag_index_prev,
2046 this_fragmentation->fragment[frag_index_prev].flags);
2047
2048 this_fragmentation->fragment[frag_index_prev].length = 0;
2049 this_fragmentation->fragment[frag_index_prev].flags = 0;
2050
2051 if (end_frame && (!begin_frame)) return; // assembling frame failed
2052 }
2053 }
2054
2055 find_frame:
2056 begin_index = this_fragmentation->start_index;
2057 uint32_t b_seq = this_fragmentation->start_seq;
2058 // Try to find a Begin sequence from the start_seq sequence to M sequence
2059 while (b_seq < Mmin)
2060 {
2061 if (this_fragmentation->fragment[begin_index].length)
2062 {
2063 if (b_seq == this_fragmentation->fragment[begin_index].seq)
2064 {
2065 if (this_fragmentation->fragment[begin_index].flags & MP_BEGIN)
2066 {
2067 int isfoundE = 0;
2068 // Adjust the new start sequence and start index
2069 this_fragmentation->start_index = begin_index;
2070 this_fragmentation->start_seq = b_seq;
2071 // Begin Sequence found, now try to found the End Sequence to complete the frame
2072 end_index = begin_index;
2073 while (b_seq < Mmin)
2074 {
2075 if (this_fragmentation->fragment[end_index].length)
2076 {
2077 if (b_seq == this_fragmentation->fragment[end_index].seq)
2078 {
2079 if (this_fragmentation->fragment[end_index].flags & MP_END)
2080 {
2081 // The End sequence was found and the frame is complete
2082 isfoundE = 1;
2083 break;
2084 }
2085 }
2086 else
2087 {
2088 // This fragment is lost, it was never completed the packet.
2089 LOG(3, this_fragmentation->fragment[end_index].sid, this_fragmentation->fragment[end_index].tid,
2090 "MPPP: (FIND END) seq_num:%d frag_index:%d flags:%02X is LOST\n",
2091 this_fragmentation->fragment[end_index].seq, begin_index,
2092 this_fragmentation->fragment[end_index].flags);
2093 // this frag is lost
2094 this_fragmentation->fragment[end_index].length = 0;
2095 this_fragmentation->fragment[end_index].flags = 0;
2096 // This frame is not complete find the next Begin
2097 break;
2098 }
2099 }
2100 else
2101 {
2102 // This frame is not complete find the next Begin if exist
2103 break;
2104 }
2105 end_index = (end_index +1) & MAXFRAGNUM_MASK;
2106 b_seq++;
2107 }
2108
2109 if (isfoundE)
2110 // The End sequence was found and the frame is complete
2111 break;
2112 else
2113 // find the next Begin
2114 begin_index = end_index;
2115 }
2116 }
2117 else
2118 {
2119 // This fragment is lost, it was never completed the packet.
2120 LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
2121 "MPPP: (FIND BEGIN) seq_num:%d frag_index:%d flags:%02X is LOST\n",
2122 this_fragmentation->fragment[begin_index].seq, begin_index,
2123 this_fragmentation->fragment[begin_index].flags);
2124 // this frag is lost
2125 this_fragmentation->fragment[begin_index].length = 0;
2126 this_fragmentation->fragment[begin_index].flags = 0;
2127 }
2128 }
2129 begin_index = (begin_index +1) & MAXFRAGNUM_MASK;
2130 b_seq++;
2131 }
2132
2133 assembling_frame:
2134 // try to assemble the frame that has the received fragment as a member
2135 // get the beginning of this frame
2136 begin_index = end_index = this_fragmentation->start_index;
2137 if (this_fragmentation->fragment[begin_index].length)
2138 {
2139 if (!(this_fragmentation->fragment[begin_index].flags & MP_BEGIN))
2140 {
2141 LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
2142 "MPPP: (NOT BEGIN) seq_num:%d frag_index:%d flags:%02X\n",
2143 this_fragmentation->fragment[begin_index].seq, begin_index,
2144 this_fragmentation->fragment[begin_index].flags);
2145 // should occur only after an "M_Offset out of range"
2146 // The start sequence must be a begin sequence
2147 this_fragmentation->start_index = (begin_index +1) & MAXFRAGNUM_MASK;
2148 this_fragmentation->start_seq++;
2149 return; // assembling frame failed
2150 }
2151 }
2152 else
2153 return; // assembling frame failed
2154
2155 // get the end of his frame
2156 while (this_fragmentation->fragment[end_index].length)
2157 {
2158 if (this_fragmentation->fragment[end_index].flags & MP_END)
2159 break;
2160
2161 end_index = (end_index +1) & MAXFRAGNUM_MASK;
2162
2163 if (end_index == this_fragmentation->start_index)
2164 return; // assembling frame failed
2165 }
2166
2167 // return if a lost fragment is found
2168 if (!(this_fragmentation->fragment[end_index].length))
2169 return; // assembling frame failed
2170
2171 // assemble the packet
2172 //assemble frame, process it, reset fragmentation
2173 uint16_t cur_len = 4; // This is set to 4 to leave 4 bytes for function processipin
2174
2175 LOG(4, s, t, "MPPP: processing fragments from %d to %d\n", begin_index, end_index);
2176 // Push to the receive buffer
2177
2178 for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)
2179 {
2180 this_frag = &this_fragmentation->fragment[i];
2181 if(cur_len + this_frag->length > MAXETHER)
2182 {
2183 LOG(2, s, t, "MPPP: discarding reassembled frames larger than MAXETHER\n");
2184 break;
2185 }
2186
2187 memcpy(this_fragmentation->reassembled_frame+cur_len, this_frag->data, this_frag->length);
2188 LOG(5, s, t, "MPPP: processing frame at %d, with len %d\n", i, this_frag->length);
2189
2190 cur_len += this_frag->length;
2191 if (i == end_index)
2192 {
2193 this_fragmentation->re_frame_len = cur_len;
2194 this_fragmentation->re_frame_begin_index = begin_index;
2195 this_fragmentation->re_frame_end_index = end_index;
2196 // Process the resassembled frame
2197 LOG(5, s, t, "MPPP: Process the reassembled frame, len=%d\n",cur_len);
2198 processmpframe(s, t, this_fragmentation->reassembled_frame, this_fragmentation->re_frame_len, 1);
2199 break;
2200 }
2201 }
2202
2203 // Set reassembled frame length to zero after processing it
2204 this_fragmentation->re_frame_len = 0;
2205 for (i = begin_index;; i = (i + 1) & MAXFRAGNUM_MASK)
2206 {
2207 this_fragmentation->fragment[i].length = 0; // Indicates that this fragment has been consumed
2208 this_fragmentation->fragment[i].flags = 0;
2209 if (i == end_index)
2210 break;
2211 }
2212
2213 // Set the new start_index and start_seq
2214 this_fragmentation->start_index = (end_index + 1) & MAXFRAGNUM_MASK;
2215 this_fragmentation->start_seq = this_fragmentation->fragment[end_index].seq + 1;
2216 LOG(4, s, t, "MPPP after assembling: start index is = %d, start seq=%d\n", this_fragmentation->start_index, this_fragmentation->start_seq);
2217
2218 begin_index = this_fragmentation->start_index;
2219 if ((this_fragmentation->fragment[begin_index].length) &&
2220 (this_fragmentation->fragment[begin_index].seq != this_fragmentation->start_seq))
2221 {
2222 LOG(3, this_fragmentation->fragment[begin_index].sid, this_fragmentation->fragment[begin_index].tid,
2223 "MPPP: (START) seq_num:%d frag_index:%d flags:%02X is LOST\n",
2224 this_fragmentation->fragment[begin_index].seq, begin_index,
2225 this_fragmentation->fragment[begin_index].flags);
2226 this_fragmentation->fragment[begin_index].length = 0;
2227 this_fragmentation->fragment[begin_index].flags = 0;
2228 }
2229
2230 if (this_fragmentation->start_seq <= Mmin)
2231 // It's possible to find other complete frame or lost frame.
2232 goto find_frame;
2233 else if ((this_fragmentation->fragment[begin_index].length) &&
2234 (this_fragmentation->fragment[begin_index].flags & MP_BEGIN))
2235 // may be that the next frame is completed
2236 goto assembling_frame;
2237
2238 return;
2239 }
2240
2241 // process IPv6 packet received
2242 //
2243 // This MUST be called with at least 4 byte behind 'p'.
2244 // (i.e. this routine writes to p[-4]).
2245 void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
2246 {
2247 struct in6_addr ip;
2248 in_addr_t ipv4;
2249
2250 CSTAT(processipv6in);
2251
2252 LOG_HEX(5, "IPv6", p, l);
2253
2254 ip = *(struct in6_addr *) (p + 8);
2255 ipv4 = ntohl(*(uint32_t *)(p + 16));
2256
2257 if (l > MAXETHER)
2258 {
2259 LOG(1, s, t, "IP packet too long %d\n", l);
2260 STAT(tunnel_rx_errors);
2261 return ;
2262 }
2263
2264 if (session[s].ppp.phase != Network || session[s].ppp.ipv6cp != Opened)
2265 return;
2266
2267 // no spoof
2268 if (session[s].ipv6address.s6_addr[0])
2269 {
2270 if ((sessionbyipv6new(ip) != s) &&
2271 (ip.s6_addr[0] != 0xFE || ip.s6_addr[1] != 0x80 || ip.s6_addr16[1] != 0 || ip.s6_addr16[2] != 0 || ip.s6_addr16[3] != 0))
2272 {
2273 char str[INET6_ADDRSTRLEN];
2274 LOG(5, s, t, "Dropping packet with spoofed IP %s\n",
2275 inet_ntop(AF_INET6, &ip, str, INET6_ADDRSTRLEN));
2276 return;
2277 }
2278 }
2279 else if ((ipv4 != session[s].ip || memcmp(&config->ipv6_prefix, &ip, 8)) && sessionbyipv6(ip) != s)
2280 {
2281 char str[INET6_ADDRSTRLEN];
2282 LOG(5, s, t, "Dropping packet with spoofed IP %s\n",
2283 inet_ntop(AF_INET6, &ip, str, INET6_ADDRSTRLEN));
2284 return;
2285 }
2286
2287 // Check if it's a Router Solicition message.
2288 if (*(p + 6) == 58 && *(p + 7) == 255 && *(p + 24) == 0xFF && *(p + 25) == 2 &&
2289 *(uint32_t *)(p + 26) == 0 && *(uint32_t *)(p + 30) == 0 &&
2290 *(uint32_t *)(p + 34) == 0 &&
2291 *(p + 38) == 0 && *(p + 39) == 2 && *(p + 40) == 133) {
2292 LOG(3, s, t, "Got IPv6 RS\n");
2293 send_ipv6_ra(s, t, &ip);
2294 return;
2295 }
2296
2297 // Check if DhcpV6, IP dst: FF02::1:2, Src Port 0x0222 (546), Dst Port 0x0223 (547)
2298 if (*(p + 6) == 17 && *(p + 24) == 0xFF && *(p + 25) == 2 &&
2299 *(uint32_t *)(p + 26) == 0 && *(uint32_t *)(p + 30) == 0 &&
2300 *(uint16_t *)(p + 34) == 0 && *(p + 36) == 0 && *(p + 37) == 1 && *(p + 38) == 0 && *(p + 39) == 2 &&
2301 *(p + 40) == 2 && *(p + 41) == 0x22 && *(p + 42) == 2 && *(p + 43) == 0x23)
2302 {
2303 dhcpv6_process(s, t, p, l);
2304 return;
2305 }
2306
2307 // Add on the tun header
2308 p -= 4;
2309 *(uint32_t *) p = htonl(PKTIPV6);
2310 l += 4;
2311
2312 // Are we throttled and a slave?
2313 if (session[s].tbf_in && !config->cluster_iam_master) {
2314 // Pass it to the master for handling.
2315 master_throttle_packet(session[s].tbf_in, p, l);
2316 return;
2317 }
2318
2319 // Are we throttled and a master??
2320 if (session[s].tbf_in && config->cluster_iam_master) {
2321 // Actually handle the throttled packets.
2322 tbf_queue_packet(session[s].tbf_in, p, l);
2323 return;
2324 }
2325
2326 // send to ethernet
2327 if (tun_write(p, l) < 0)
2328 {
2329 STAT(tun_tx_errors);
2330 LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
2331 l, strerror(errno), tunfd, p);
2332
2333 return;
2334 }
2335
2336 p += 4;
2337 l -= 4;
2338
2339 if (session[s].snoop_ip && session[s].snoop_port)
2340 {
2341 // Snooping this session
2342 snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port);
2343 }
2344
2345 update_sessions_in_stat(s, l);
2346
2347 eth_tx += l;
2348
2349 STAT(tun_tx_packets);
2350 INC_STAT(tun_tx_bytes, l);
2351 }
2352
2353 //
2354 // Helper routine for the TBF filters.
2355 // Used to send queued data in from the user.
2356 //
2357 void send_ipin(sessionidt s, uint8_t *buf, int len)
2358 {
2359 LOG_HEX(5, "IP in throttled", buf, len);
2360
2361 if (write(tunfd, buf, len) < 0)
2362 {
2363 STAT(tun_tx_errors);
2364 LOG(0, 0, 0, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
2365 len, strerror(errno), tunfd, buf);
2366
2367 return;
2368 }
2369
2370 buf += 4;
2371 len -= 4;
2372
2373 if (session[s].snoop_ip && session[s].snoop_port)
2374 {
2375 // Snooping this session
2376 snoop_send_packet(buf, len, session[s].snoop_ip, session[s].snoop_port);
2377 }
2378
2379 // Increment packet counters
2380 increment_counter(&session[s].cin, &session[s].cin_wrap, len);
2381 session[s].cin_delta += len;
2382 session[s].pin++;
2383
2384 sess_local[s].cin += len;
2385 sess_local[s].pin++;
2386
2387 eth_tx += len;
2388
2389 STAT(tun_tx_packets);
2390 INC_STAT(tun_tx_bytes, len - 4);
2391 }
2392
2393
2394 // Process CCP messages
2395 void processccp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
2396 {
2397 uint8_t b[MAXETHER];
2398 uint8_t *q;
2399
2400 CSTAT(processccp);
2401
2402 LOG_HEX(5, "CCP", p, l);
2403
2404 if (session[s].ppp.phase < Network)
2405 {
2406 LOG(2, s, t, "CCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
2407 return;
2408 }
2409
2410 if (l < 1)
2411 {
2412 LOG(1, s, t, "Short CCP packet\n");
2413 STAT(tunnel_rx_errors);
2414 }
2415
2416 LOG(4, s, t, "CCP: recv %s\n", ppp_code(*p));
2417 if (*p == ConfigAck)
2418 {
2419 switch (session[s].ppp.ccp)
2420 {
2421 case RequestSent:
2422 initialise_restart_count(s, ccp);
2423 change_state(s, ccp, AckReceived);
2424 break;
2425
2426 case AckReceived:
2427 case Opened:
2428 LOG(2, s, t, "CCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ccp));
2429 sendccp(s, t);
2430 change_state(s, ccp, RequestSent);
2431 break;
2432
2433 case AckSent:
2434 LOG(3, s, t, "CCP: Opened\n");
2435 change_state(s, ccp, Opened);
2436 break;
2437
2438 default:
2439 LOG(2, s, t, "CCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ccp));
2440 }
2441 }
2442 else if (*p == ConfigReq)
2443 {
2444 if (l < 6) // accept no compression
2445 *p = ConfigAck;
2446 else // compression requested--reject
2447 *p = ConfigRej;
2448
2449 q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP, 0, 0, 0);
2450 if (!q) return;
2451
2452 switch (session[s].ppp.ccp)
2453 {
2454 case Closed:
2455 q = makeppp(b, sizeof(b), p, 2, s, t, PPPCCP, 0, 0, 0);
2456 if (!q) return;
2457 *q = TerminateAck;
2458 *((uint16_t *) (q + 2)) = htons(l = 4);
2459 break;
2460
2461 case Stopped:
2462 initialise_restart_count(s, ccp);
2463 sendccp(s, t);
2464 if (*q == ConfigAck)
2465 change_state(s, ccp, AckSent);
2466 else
2467 change_state(s, ccp, RequestSent);
2468
2469 break;
2470
2471 case RequestSent:
2472 if (*q == ConfigAck)
2473 change_state(s, ccp, AckSent);
2474
2475 break;
2476
2477 case AckReceived:
2478 if (*q == ConfigAck)
2479 change_state(s, ccp, Opened);
2480
2481 break;
2482
2483 case Opened:
2484 initialise_restart_count(s, ccp);
2485 sendccp(s, t);
2486 /* fallthrough */
2487
2488 case AckSent:
2489 if (*q == ConfigAck)
2490 change_state(s, ccp, AckSent);
2491 else
2492 change_state(s, ccp, RequestSent);
2493
2494 break;
2495
2496 default:
2497 LOG(2, s, t, "CCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ccp));
2498 return;
2499 }
2500
2501 LOG(4, s, t, "CCP: send %s\n", ppp_code(*q));
2502 tunnelsend(b, l + (q - b), t);
2503 }
2504 else if (*p == TerminateReq)
2505 {
2506 *p = TerminateAck;
2507 q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP, 0, 0, 0);
2508 if (!q) return;
2509 LOG(3, s, t, "CCP: send %s\n", ppp_code(*q));
2510 tunnelsend(b, l + (q - b), t);
2511 change_state(s, ccp, Stopped);
2512 }
2513 else if (*p != CodeRej)
2514 {
2515 ppp_code_rej(s, t, PPPCCP, "CCP", p, l, b, sizeof(b));
2516 }
2517 }
2518
2519 // send a CHAP challenge
2520 void sendchap(sessionidt s, tunnelidt t)
2521 {
2522 uint8_t b[MAXETHER];
2523 uint16_t r;
2524 uint8_t *q;
2525
2526 CSTAT(sendchap);
2527
2528 r = radiusnew(s);
2529 if (!r)
2530 {
2531 LOG(1, s, t, "No RADIUS to send challenge\n");
2532 STAT(tunnel_tx_errors);
2533 return;
2534 }
2535
2536 LOG(1, s, t, "Send CHAP challenge\n");
2537
2538 radius[r].chap = 1; // CHAP not PAP
2539 radius[r].id++;
2540 if (radius[r].state != RADIUSCHAP)
2541 radius[r].try = 0;
2542
2543 radius[r].state = RADIUSCHAP;
2544 radius[r].retry = backoff(radius[r].try++);
2545 if (radius[r].try > 5)
2546 {
2547 sessionshutdown(s, "CHAP timeout.", CDN_ADMIN_DISC, TERM_REAUTHENTICATION_FAILURE);
2548 STAT(tunnel_tx_errors);
2549 return ;
2550 }
2551 q = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP, 0, 0, 0);
2552 if (!q) return;
2553
2554 *q = 1; // challenge
2555 q[1] = radius[r].id; // ID
2556 q[4] = 16; // value size (size of challenge)
2557 memcpy(q + 5, radius[r].auth, 16); // challenge
2558 strcpy((char *) q + 21, config->multi_n_hostname[tunnel[t].indexudp][0]?config->multi_n_hostname[tunnel[t].indexudp]:hostname); // our name
2559 *(uint16_t *) (q + 2) = htons(strlen(config->multi_n_hostname[tunnel[t].indexudp][0]?config->multi_n_hostname[tunnel[t].indexudp]:hostname) + 21); // length
2560 tunnelsend(b, strlen(config->multi_n_hostname[tunnel[t].indexudp][0]?config->multi_n_hostname[tunnel[t].indexudp]:hostname) + 21 + (q - b), t); // send it
2561 }
2562
2563 // fill in a L2TP message with a PPP frame,
2564 // returns start of PPP frame
2565 uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype, uint8_t prio, bundleidt bid, uint8_t mp_bits)
2566 {
2567 uint16_t hdr = 0x0002; // L2TP with no options
2568 uint16_t type = mtype;
2569 uint8_t *start = b;
2570
2571 if (t == TUNNEL_ID_PPPOE)
2572 {
2573 return pppoe_makeppp(b, size, p, l, s, t, mtype, prio, bid, mp_bits);
2574 }
2575
2576 if (size < 16) // Need more space than this!!
2577 {
2578 LOG(0, s, t, "makeppp buffer too small for L2TP header (size=%d)\n", size);
2579 return NULL;
2580 }
2581
2582 if (prio) hdr |= 0x0100; // set priority bit
2583
2584 *(uint16_t *) (b + 0) = htons(hdr);
2585 *(uint16_t *) (b + 2) = htons(tunnel[t].far); // tunnel
2586 *(uint16_t *) (b + 4) = htons(session[s].far); // session
2587 b += 6;
2588
2589 // Check whether this session is part of multilink
2590 if (bid)
2591 {
2592 if (bundle[bid].num_of_links > 1)
2593 type = PPPMP; // Change PPP message type to the PPPMP
2594 else
2595 bid = 0;
2596 }
2597
2598 if (type == PPPLCP || !(session[s].flags & SESSION_ACFC))
2599 {
2600 *(uint16_t *) b = htons(0xFF03); // HDLC header
2601 b += 2;
2602 }
2603
2604 if (type < 0x100 && session[s].flags & SESSION_PFC)
2605 {
2606 *b++ = type;
2607 }
2608 else
2609 {
2610 *(uint16_t *) b = htons(type);
2611 b += 2;
2612 }
2613
2614 if (bid)
2615 {
2616 // Set the sequence number and (B)egin (E)nd flags
2617 if (session[s].mssf)
2618 {
2619 // Set the multilink bits
2620 uint16_t bits_send = mp_bits;
2621 *(uint16_t *) b = htons((bundle[bid].seq_num_t & 0x0FFF)|bits_send);
2622 b += 2;
2623 }
2624 else
2625 {
2626 *(uint32_t *) b = htonl(bundle[bid].seq_num_t);
2627 // Set the multilink bits
2628 *b = mp_bits;
2629 b += 4;
2630 }
2631
2632 bundle[bid].seq_num_t++;
2633
2634 // Add the message type if this fragment has the begin bit set
2635 if (mp_bits & MP_BEGIN)
2636 {
2637 //*b++ = mtype; // The next two lines are instead of this
2638 *(uint16_t *) b = htons(mtype); // Message type
2639 b += 2;
2640 }
2641 }
2642
2643 if ((b - start) + l > size)
2644 {
2645 LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%td)\n", size, (b - start) + l);
2646 return NULL;
2647 }
2648
2649 // Copy the payload
2650 if (p && l)
2651 memcpy(b, p, l);
2652
2653 return b;
2654 }
2655
2656 // fill in a L2TP message with a PPP frame,
2657 // returns start of PPP frame
2658 //(note: THIS ROUTINE CAN WRITES TO p[-28]).
2659 uint8_t *opt_makeppp(uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype, uint8_t prio, bundleidt bid, uint8_t mp_bits)
2660 {
2661 uint16_t hdr = 0x0002; // L2TP with no options
2662 uint16_t type = mtype;
2663 uint8_t *b = p;
2664
2665 if (t == TUNNEL_ID_PPPOE)
2666 {
2667 return opt_pppoe_makeppp(p, l, s, t, mtype, prio, bid, mp_bits);
2668 }
2669
2670 // Check whether this session is part of multilink
2671 if (bid)
2672 {
2673 if (bundle[bid].num_of_links > 1)
2674 type = PPPMP; // Change PPP message type to the PPPMP
2675 else
2676 bid = 0;
2677 }
2678
2679 if (bid)
2680 {
2681 // Add the message type if this fragment has the begin bit set
2682 if (mp_bits & MP_BEGIN)
2683 {
2684 b -= 2;
2685 *(uint16_t *) b = htons(mtype); // Message type
2686 }
2687
2688 // Set the sequence number and (B)egin (E)nd flags
2689 if (session[s].mssf)
2690 {
2691 // Set the multilink bits
2692 uint16_t bits_send = mp_bits;
2693 b -= 2;
2694 *(uint16_t *) b = htons((bundle[bid].seq_num_t & 0x0FFF)|bits_send);
2695 }
2696 else
2697 {
2698 b -= 4;
2699 *(uint32_t *) b = htonl(bundle[bid].seq_num_t);
2700 // Set the multilink bits
2701 *b = mp_bits;
2702 }
2703
2704 bundle[bid].seq_num_t++;
2705 }
2706
2707 if (type < 0x100 && session[s].flags & SESSION_PFC)
2708 {
2709 b--;
2710 *b = type;
2711 }
2712 else
2713 {
2714 b -= 2;
2715 *(uint16_t *) b = htons(type);
2716 }
2717
2718 if (type == PPPLCP || !(session[s].flags & SESSION_ACFC))
2719 {
2720 b -= 2;
2721 *(uint16_t *) b = htons(0xFF03); // HDLC header
2722 }
2723
2724 if (prio) hdr |= 0x0100; // set priority bit
2725 b -= 2;
2726 *(uint16_t *) b = htons(session[s].far); // session
2727 b -= 2;
2728 *(uint16_t *) b = htons(tunnel[t].far); // tunnel
2729 b -= 2;
2730 *(uint16_t *) b = htons(hdr);
2731
2732 return b;
2733 }
2734
2735 static int add_lcp_auth(uint8_t *b, int size, int authtype)
2736 {
2737 int len = 0;
2738 if ((authtype == AUTHCHAP && size < 5) || size < 4)
2739 return 0;
2740
2741 *b++ = 3; // Authentication-Protocol
2742 if (authtype == AUTHCHAP)
2743 {
2744 len = *b++ = 5; // length
2745 *(uint16_t *) b = htons(PPPCHAP); b += 2;
2746 *b++ = 5; // MD5
2747 }
2748 else if (authtype == AUTHPAP)
2749 {
2750 len = *b++ = 4; // length
2751 *(uint16_t *) b = htons(PPPPAP); b += 2;
2752 }
2753 else
2754 {
2755 LOG(0, 0, 0, "add_lcp_auth called with unsupported auth type %d\n", authtype);
2756 }
2757
2758 return len;
2759 }
2760
2761 // Send LCP ConfigReq for MRU, authentication type and magic no
2762 void sendlcp(sessionidt s, tunnelidt t)
2763 {
2764 uint8_t b[500], *q, *l;
2765 int authtype = sess_local[s].lcp_authtype;
2766
2767 if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPLCP, 0, 0, 0)))
2768 return;
2769
2770 LOG(3, s, t, "LCP: send ConfigReq%s%s%s including MP options\n",
2771 authtype ? " (" : "",
2772 authtype ? (authtype == AUTHCHAP ? "CHAP" : "PAP") : "",
2773 authtype ? ")" : "");
2774
2775 l = q;
2776 *l++ = ConfigReq;
2777 *l++ = ++sess_local[s].lcp_ident; // ID
2778
2779 l += 2; //Save space for length
2780
2781 if (sess_local[s].ppp_mru)
2782 {
2783 *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4)
2784 *(uint16_t *) l = htons(sess_local[s].ppp_mru); l += 2;
2785 }
2786
2787 if (authtype)
2788 l += add_lcp_auth(l, sizeof(b) - (l - b), authtype);
2789
2790 if (session[s].magic)
2791 {
2792 *l++ = 5; *l++ = 6; // Magic-Number (length 6)
2793 *(uint32_t *) l = htonl(session[s].magic);
2794 l += 4;
2795 }
2796
2797 if (sess_local[s].mp_mrru)
2798 {
2799 *l++ = 17; *l++ = 4; // Multilink Max-Receive-Reconstructed-Unit (length 4)
2800 *(uint16_t *) l = htons(sess_local[s].mp_mrru); l += 2;
2801 }
2802
2803 if (sess_local[s].mp_epdis)
2804 {
2805 *l++ = 19; *l++ = 7; // Multilink Endpoint Discriminator (length 7)
2806 *l++ = IPADDR; // Endpoint Discriminator class
2807 *(uint32_t *) l = htonl(sess_local[s].mp_epdis);
2808 l += 4;
2809 }
2810
2811 *(uint16_t *)(q + 2) = htons(l - q); // Length
2812
2813 LOG_HEX(5, "PPPLCP", q, l - q);
2814 if (config->debug > 3) dumplcp(q, l - q);
2815
2816 tunnelsend(b, (l - b), t);
2817 restart_timer(s, lcp);
2818 }
2819
2820 // Send CCP request for no compression
2821 void sendccp(sessionidt s, tunnelidt t)
2822 {
2823 uint8_t b[500], *q;
2824
2825 if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPCCP, 0, 0, 0)))
2826 return;
2827
2828 LOG(3, s, t, "CCP: send ConfigReq (no compression)\n");
2829
2830 *q = ConfigReq;
2831 *(q + 1) = ++sess_local[s].lcp_ident; // ID
2832 *(uint16_t *)(q + 2) = htons(4); // Length
2833
2834 LOG_HEX(5, "PPPCCP", q, 4);
2835 tunnelsend(b, (q - b) + 4 , t);
2836 restart_timer(s, ccp);
2837 }
2838
2839 // Reject unknown/unconfigured protocols
2840 void protoreject(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint16_t proto)
2841 {
2842
2843 uint8_t buf[MAXETHER];
2844 uint8_t *q;
2845 int mru = session[s].mru;
2846 if (mru < MINMTU) mru = MINMTU;
2847 if (mru > sizeof(buf)) mru = sizeof(buf);
2848
2849 l += 6;
2850 if (l > mru) l = mru;
2851
2852 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPLCP, 0, 0, 0);
2853 if (!q) return;
2854
2855 *q = ProtocolRej;
2856 *(q + 1) = ++sess_local[s].lcp_ident;
2857 *(uint16_t *)(q + 2) = htons(l);
2858 *(uint16_t *)(q + 4) = htons(proto);
2859 memcpy(q + 6, p, l - 6);
2860
2861 if (proto == PPPIPV6CP)
2862 LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
2863 else
2864 LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
2865
2866 tunnelsend(buf, l + (q - buf), t);
2867 }
for cloning use: "git clone git://git.sameswireless.fr/l2tpns.git" ; For add to your sources.list: "deb http://package.sameswifi.fr/ jessie main"