52a813d08becac0654d9147a1b7eb168fc984c25
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.23 2004-08-26 04:43:52 fred_nerk Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <stdarg.h>
23 #include <stdlib.h>
24 #include <stdio.h>
25 #include <string.h>
26 #include <sys/ioctl.h>
27 #include <sys/socket.h>
28 #include <sys/stat.h>
29 #include <sys/time.h>
30 #include <sys/resource.h>
31 #include <sys/wait.h>
32 #include <linux/if.h>
33 #include <stddef.h>
34 #include <time.h>
35 #include <dlfcn.h>
36 #include <unistd.h>
37 #include <sched.h>
38 #include <sys/sysinfo.h>
39 #include <libcli.h>
40
41 #include "md5.h"
42 #include "l2tpns.h"
43 #include "cluster.h"
44 #include "plugin.h"
45 #include "ll.h"
46 #include "constants.h"
47 #include "control.h"
48 #include "util.h"
49 #include "tbf.h"
50
51 // Globals
52 struct configt *config = NULL; // all configuration
53 int tunfd = -1; // tun interface file handle. (network device)
54 int udpfd = -1; // UDP file handle
55 int controlfd = -1; // Control signal handle
56 int snoopfd = -1; // UDP file handle for sending out intercept data
57 int *radfds = NULL; // RADIUS requests file handles
58 int ifrfd = -1; // File descriptor for routing, etc
59 time_t basetime = 0; // base clock
60 char hostname[1000] = ""; // us.
61 int tunidx; // ifr_ifindex of tun device
62 u32 sessionid = 0; // session id for radius accounting
63 int syslog_log = 0; // are we logging to syslog
64 FILE *log_stream = NULL; // file handle for direct logging (i.e. direct into file, not via syslog).
65 extern int cluster_sockfd; // Intra-cluster communications socket.
66 u32 last_sid = 0; // Last used PPP SID. Can I kill this?? -- mo
67 int clifd = 0; // Socket listening for CLI connections.
68
69 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
70 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
71
72 static void *ip_hash[256]; // Mapping from IP address to session structures.
73
74 u32 udp_tx = 0, udp_rx = 0, udp_rx_pkt = 0; // Global traffic counters.
75 u32 eth_tx = 0, eth_rx = 0, eth_rx_pkt = 0;
76 u32 ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
77 time_t time_now = 0; // Current time in seconds since epoch.
78 char time_now_string[64] = {0}; // Current time as a string.
79 char main_quit = 0; // True if we're in the process of exiting.
80 char *_program_name = NULL;
81 linked_list *loaded_plugins;
82 linked_list *plugins[MAX_PLUGIN_TYPES];
83
84 #ifdef BGP
85 #include "bgp.h"
86 struct bgp_peer *bgp_peers = 0;
87 struct bgp_route_list *bgp_routes = 0;
88 int bgp_configured = 0;
89 #endif /* BGP */
90
91 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
92 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(struct configt, MEMBER), membersize(struct configt, MEMBER), TYPE }
93
94 struct config_descriptt config_values[] = {
95 CONFIG("debug", debug, INT),
96 CONFIG("log_file", log_filename, STRING),
97 CONFIG("pid_file", pid_file, STRING),
98 CONFIG("l2tp_secret", l2tpsecret, STRING),
99 CONFIG("primary_dns", default_dns1, IP),
100 CONFIG("secondary_dns", default_dns2, IP),
101 CONFIG("save_state", save_state, BOOL),
102 CONFIG("primary_radius", radiusserver[0], IP),
103 CONFIG("secondary_radius", radiusserver[1], IP),
104 CONFIG("primary_radius_port",radiusport[0], SHORT),
105 CONFIG("secondary_radius_port",radiusport[1], SHORT),
106 CONFIG("radius_accounting", radius_accounting, BOOL),
107 CONFIG("radius_secret", radiussecret, STRING),
108 CONFIG("bind_address", bind_address, IP),
109 CONFIG("send_garp", send_garp, BOOL),
110 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
111 CONFIG("accounting_dir", accounting_dir, STRING),
112 CONFIG("setuid", target_uid, INT),
113 CONFIG("dump_speed", dump_speed, BOOL),
114 CONFIG("cleanup_interval", cleanup_interval, INT),
115 CONFIG("multi_read_count", multi_read_count, INT),
116 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
117 CONFIG("lock_pages", lock_pages, BOOL),
118 CONFIG("icmp_rate", icmp_rate, INT),
119 CONFIG("cluster_address", cluster_address, IP),
120 CONFIG("cluster_interface", cluster_interface, STRING),
121 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
122 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
123 #ifdef BGP
124 CONFIG("as_number", as_number, SHORT),
125 CONFIG("bgp_peer1", bgp_peer[0], STRING),
126 CONFIG("bgp_peer1_as", bgp_peer_as[0], SHORT),
127 CONFIG("bgp_peer2", bgp_peer[1], STRING),
128 CONFIG("bgp_peer2_as", bgp_peer_as[1], SHORT),
129 #endif /* BGP */
130 { NULL, 0, 0, 0 },
131 };
132
133 char *plugin_functions[] = {
134 NULL,
135 "plugin_pre_auth",
136 "plugin_post_auth",
137 "plugin_packet_rx",
138 "plugin_packet_tx",
139 "plugin_timer",
140 "plugin_new_session",
141 "plugin_kill_session",
142 "plugin_control",
143 "plugin_radius_response",
144 "plugin_become_master",
145 "plugin_new_session_master",
146 };
147
148 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
149
150 tunnelt *tunnel = NULL; // Array of tunnel structures.
151 sessiont *session = NULL; // Array of session structures.
152 sessioncountt *sess_count = NULL; // Array of partial per-session traffic counters.
153 radiust *radius = NULL; // Array of radius structures.
154 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
155 controlt *controlfree = 0;
156 struct Tstats *_statistics = NULL;
157 #ifdef RINGBUFFER
158 struct Tringbuffer *ringbuffer = NULL;
159 #endif
160
161 void sigalrm_handler(int);
162 void sighup_handler(int);
163 void sigterm_handler(int);
164 void sigquit_handler(int);
165 void sigchild_handler(int);
166 void read_config_file();
167 void read_state();
168 void dump_state();
169 void tunnel_clean();
170 tunnelidt new_tunnel();
171 void update_config();
172
173 static void cache_ipmap(ipt ip, int s);
174 static void uncache_ipmap(ipt ip);
175
176 // return internal time (10ths since process startup)
177 clockt now(void)
178 {
179 struct timeval t;
180 gettimeofday(&t, 0);
181 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
182 }
183
184 // work out a retry time based on try number
185 // This is a straight bounded exponential backoff.
186 // Maximum re-try time is 32 seconds. (2^5).
187 clockt backoff(u8 try)
188 {
189 if (try > 5) try = 5; // max backoff
190 return now() + 10 * (1 << try);
191 }
192
193
194 //
195 // Log a debug message.
196 //
197 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
198 {
199 static char message[65536] = {0};
200 static char message2[65536] = {0};
201 va_list ap;
202
203 #ifdef RINGBUFFER
204 if (ringbuffer)
205 {
206 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
207 ringbuffer->tail = 0;
208 if (ringbuffer->tail == ringbuffer->head)
209 if (++ringbuffer->head >= RINGBUFFER_SIZE)
210 ringbuffer->head = 0;
211
212 ringbuffer->buffer[ringbuffer->tail].level = level;
213 ringbuffer->buffer[ringbuffer->tail].address = address;
214 ringbuffer->buffer[ringbuffer->tail].session = s;
215 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
216 va_start(ap, format);
217 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
218 va_end(ap);
219 }
220 #endif
221
222 if (config->debug < level) return;
223
224 va_start(ap, format);
225 if (log_stream)
226 {
227 vsnprintf(message2, 65535, format, ap);
228 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
229 fprintf(log_stream, "%s", message);
230 }
231 else if (syslog_log)
232 {
233 vsnprintf(message2, 65535, format, ap);
234 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
235 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
236 }
237 va_end(ap);
238 }
239
240 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize)
241 {
242 int i, j;
243 const u8 *d = (const u8 *)data;
244
245 if (config->debug < level) return;
246
247 // No support for log_hex to syslog
248 if (log_stream)
249 {
250 log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
251 setvbuf(log_stream, NULL, _IOFBF, 16384);
252
253 for (i = 0; i < maxsize; )
254 {
255 fprintf(log_stream, "%4X: ", i);
256 for (j = i; j < maxsize && j < (i + 16); j++)
257 {
258 fprintf(log_stream, "%02X ", d[j]);
259 if (j == i + 7)
260 fputs(": ", log_stream);
261 }
262
263 for (; j < i + 16; j++)
264 {
265 fputs(" ", log_stream);
266 if (j == i + 7)
267 fputs(": ", log_stream);
268 }
269
270 fputs(" ", log_stream);
271 for (j = i; j < maxsize && j < (i + 16); j++)
272 {
273 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
274 fputc(d[j], log_stream);
275 else
276 fputc('.', log_stream);
277
278 if (j == i + 7)
279 fputs(" ", log_stream);
280 }
281
282 i = j;
283 fputs("\n", log_stream);
284 }
285
286 fflush(log_stream);
287 setbuf(log_stream, NULL);
288 }
289 }
290
291
292 // Add a route
293 //
294 // This adds it to the routing table, advertises it
295 // via iBGP if enabled, and stuffs it into the
296 // 'sessionbyip' cache.
297 //
298 // 'ip' and 'mask' must be in _host_ order.
299 //
300 void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
301 {
302 struct rtentry r;
303 int i;
304
305 if (!mask) mask = 0xffffffff;
306
307 ip &= mask; // Force the ip to be the first one in the route.
308
309 memset(&r, 0, sizeof(r));
310 r.rt_dev = config->tundevice;
311 r.rt_dst.sa_family = AF_INET;
312 *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
313 r.rt_gateway.sa_family = AF_INET;
314 *(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
315 r.rt_genmask.sa_family = AF_INET;
316 *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
317 r.rt_flags = (RTF_UP | RTF_STATIC);
318 if (gw)
319 r.rt_flags |= RTF_GATEWAY;
320 else if (mask == 0xffffffff)
321 r.rt_flags |= RTF_HOST;
322
323 log(1, ip, 0, 0, "Route %s %u.%u.%u.%u/%u.%u.%u.%u %u.%u.%u.%u\n",
324 add ? "add" : "del",
325 ip >> 24, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff,
326 mask >> 24, mask >> 16 & 0xff, mask >> 8 & 0xff, mask & 0xff,
327 gw >> 24, gw >> 16 & 0xff, gw >> 8 & 0xff, gw & 0xff);
328
329 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
330 log(0, 0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
331
332 #ifdef BGP
333 if (add)
334 bgp_add_route(htonl(ip), htonl(mask));
335 else
336 bgp_del_route(htonl(ip), htonl(mask));
337 #endif /* BGP */
338
339 // Add/Remove the IPs to the 'sessionbyip' cache.
340 // Note that we add the zero address in the case of
341 // a network route. Roll on CIDR.
342
343 // Note that 's == 0' implies this is the address pool.
344 // We still cache it here, because it will pre-fill
345 // the malloc'ed tree.
346
347 if (s)
348 {
349 if (!add) // Are we deleting a route?
350 s = 0; // Caching the session as '0' is the same as uncaching.
351
352 for (i = ip; (i&mask) == (ip&mask) ; ++i)
353 cache_ipmap(i, s);
354 }
355 }
356
357 //
358 // Set up TUN interface
359 void inittun(void)
360 {
361 struct ifreq ifr;
362 struct sockaddr_in sin = {0};
363 memset(&ifr, 0, sizeof(ifr));
364 ifr.ifr_flags = IFF_TUN;
365
366 tunfd = open(TUNDEVICE, O_RDWR);
367 if (tunfd < 0)
368 { // fatal
369 log(0, 0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
370 exit(1);
371 }
372 {
373 int flags = fcntl(tunfd, F_GETFL, 0);
374 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
375 }
376 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
377 {
378 log(0, 0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
379 exit(1);
380 }
381 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
382 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
383 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
384
385 sin.sin_family = AF_INET;
386 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
387 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
388
389 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
390 {
391 log(0, 0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
392 exit(1);
393 }
394 /* Bump up the qlen to deal with bursts from the network */
395 ifr.ifr_qlen = 1000;
396 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
397 {
398 log(0, 0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
399 exit(1);
400 }
401 ifr.ifr_flags = IFF_UP;
402 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
403 {
404 log(0, 0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
405 exit(1);
406 }
407 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
408 {
409 log(0, 0, 0, 0, "Error setting tun ifindex: %s\n", strerror(errno));
410 exit(1);
411 }
412 tunidx = ifr.ifr_ifindex;
413 }
414
415 // set up UDP port
416 void initudp(void)
417 {
418 int on = 1;
419 struct sockaddr_in addr;
420
421 // Tunnel
422 memset(&addr, 0, sizeof(addr));
423 addr.sin_family = AF_INET;
424 addr.sin_port = htons(L2TPPORT);
425 addr.sin_addr.s_addr = config->bind_address;
426 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
427 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
428 {
429 int flags = fcntl(udpfd, F_GETFL, 0);
430 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
431 }
432 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
433 {
434 log(0, 0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
435 exit(1);
436 }
437 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
438
439 // Control
440 memset(&addr, 0, sizeof(addr));
441 addr.sin_family = AF_INET;
442 addr.sin_port = htons(1702);
443 controlfd = socket(AF_INET, SOCK_DGRAM, 17);
444 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
445 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
446 {
447 log(0, 0, 0, 0, "Error in control bind: %s\n", strerror(errno));
448 exit(1);
449 }
450 }
451
452 //
453 // Find session by IP, < 1 for not found
454 //
455 // Confusingly enough, this 'ip' must be
456 // in _network_ order. This being the common
457 // case when looking it up from IP packet headers.
458 //
459 // We actually use this cache for two things.
460 // #1. For used IP addresses, this maps to the
461 // session ID that it's used by.
462 // #2. For un-used IP addresses, this maps to the
463 // index into the pool table that contains that
464 // IP address.
465 //
466
467 int lookup_ipmap(ipt ip)
468 {
469 u8 *a = (u8 *)&ip;
470 char **d = (char **) ip_hash;
471 int s;
472
473 if (!(d = (char **) d[(size_t) *a++])) return 0;
474 if (!(d = (char **) d[(size_t) *a++])) return 0;
475 if (!(d = (char **) d[(size_t) *a++])) return 0;
476
477 s = (ipt) d[(size_t) *a];
478 return s;
479 }
480
481 sessionidt sessionbyip(ipt ip)
482 {
483 int s = lookup_ipmap(ip);
484 CSTAT(call_sessionbyip);
485
486 if (s > 0 && s < MAXSESSION && session[s].tunnel)
487 return s;
488 return 0;
489 }
490
491 //
492 // Take an IP address in HOST byte order and
493 // add it to the sessionid by IP cache.
494 //
495 // (It's actually cached in network order)
496 //
497 static void cache_ipmap(ipt ip, int s)
498 {
499 ipt nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char*)(&ip))[0]
500 u8 *a = (u8 *) &nip;
501 char **d = (char **) ip_hash;
502 int i;
503
504 for (i = 0; i < 3; i++)
505 {
506 if (!d[(size_t) a[i]])
507 {
508 if (!(d[(size_t) a[i]] = calloc(256, sizeof (void *))))
509 return;
510 }
511
512 d = (char **) d[(size_t) a[i]];
513 }
514
515 d[(size_t) a[3]] = (char *)((int)s);
516
517 if (s > 0)
518 log(4, ip, s, session[s].tunnel, "Caching ip address %s\n", inet_toa(nip));
519 else if (s == 0)
520 log(4, ip, 0, 0, "Un-caching ip address %s\n", inet_toa(nip));
521 // else a map to an ip pool index.
522 }
523
524 static void uncache_ipmap(ipt ip)
525 {
526 cache_ipmap(ip, 0); // Assign it to the NULL session.
527 }
528
529 //
530 // CLI list to dump current ipcache.
531 //
532 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
533 {
534 char **d = (char **) ip_hash, **e, **f, **g;
535 int i, j, k, l;
536 int count = 0;
537
538 if (CLI_HELP_REQUESTED)
539 return CLI_HELP_NO_ARGS;
540
541 cli_print(cli, "%7s %s", "Sess#", "IP Address");
542
543 for (i = 0; i < 256; ++i)
544 {
545 if (!d[i])
546 continue;
547 e = (char**) d[i];
548 for (j = 0; j < 256; ++j)
549 {
550 if (!e[j])
551 continue;
552 f = (char**) e[j];
553 for (k = 0; k < 256; ++k)
554 {
555 if (!f[k])
556 continue;
557 g = (char**)f[k];
558 for (l = 0; l < 256; ++l)
559 {
560 if (!g[l])
561 continue;
562 cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
563 ++count;
564 }
565 }
566 }
567 }
568 cli_print(cli, "%d entries in cache", count);
569 return CLI_OK;
570 }
571
572
573 // Find session by username, 0 for not found
574 // walled garden users aren't authenticated, so the username is
575 // reasonably useless. Ignore them to avoid incorrect actions
576 //
577 // This is VERY inefficent. Don't call it often. :)
578 //
579 sessionidt sessionbyuser(char *username)
580 {
581 int s;
582 CSTAT(call_sessionbyuser);
583
584 for (s = 1; s < MAXSESSION ; ++s)
585 {
586 if (session[s].walled_garden)
587 continue; // Skip walled garden users.
588
589 if (!strncmp(session[s].user, username, 128))
590 return s;
591
592 }
593 return 0; // Not found.
594 }
595
596 void send_garp(ipt ip)
597 {
598 int s;
599 struct ifreq ifr;
600 u8 mac[6];
601
602 s = socket(PF_INET, SOCK_DGRAM, 0);
603 if (s < 0)
604 {
605 log(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
606 return;
607 }
608 memset(&ifr, 0, sizeof(ifr));
609 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
610 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
611 {
612 log(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
613 close(s);
614 return;
615 }
616 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
617 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
618 {
619 log(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
620 close(s);
621 return;
622 }
623 close(s);
624 sendarp(ifr.ifr_ifindex, mac, ip);
625 }
626
627 // Find session by username, 0 for not found
628 sessiont *sessiontbysessionidt(sessionidt s)
629 {
630 if (!s || s > MAXSESSION) return NULL;
631 return &session[s];
632 }
633
634 sessionidt sessionidtbysessiont(sessiont *s)
635 {
636 sessionidt val = s-session;
637 if (s < session || val > MAXSESSION) return 0;
638 return val;
639 }
640
641 // actually send a control message for a specific tunnel
642 void tunnelsend(u8 * buf, u16 l, tunnelidt t)
643 {
644 struct sockaddr_in addr;
645
646 CSTAT(call_tunnelsend);
647
648 if (!t)
649 {
650 static int backtrace_count = 0;
651 log(0, 0, 0, t, "tunnelsend called with 0 as tunnel id\n");
652 STAT(tunnel_tx_errors);
653 log_backtrace(backtrace_count, 5)
654 return;
655 }
656
657 if (!tunnel[t].ip)
658 {
659 static int backtrace_count = 0;
660 log(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
661 log_backtrace(backtrace_count, 5)
662 STAT(tunnel_tx_errors);
663 return;
664 }
665 memset(&addr, 0, sizeof(addr));
666 addr.sin_family = AF_INET;
667 *(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
668 addr.sin_port = htons(tunnel[t].port);
669
670 // sequence expected, if sequence in message
671 if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
672
673 // If this is a control message, deal with retries
674 if (*buf & 0x80)
675 {
676 tunnel[t].last = time_now; // control message sent
677 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
678 if (tunnel[t].try > 1)
679 {
680 STAT(tunnel_retries);
681 log(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
682 }
683 }
684
685 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
686 {
687 log(0, tunnel[t].ip, ntohs((*(u16 *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
688 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
689 STAT(tunnel_tx_errors);
690 return;
691 }
692
693 log_hex(5, "Send Tunnel Data", buf, l);
694 STAT(tunnel_tx_packets);
695 INC_STAT(tunnel_tx_bytes, l);
696 }
697
698 //
699 // Tiny helper function to write data to
700 // the 'tun' device.
701 //
702 int tun_write(u8 * data, int size)
703 {
704 return write(tunfd, data, size);
705 }
706
707 // process outgoing (to tunnel) IP
708 //
709 void processipout(u8 * buf, int len)
710 {
711 sessionidt s;
712 sessiont *sp;
713 tunnelidt t;
714 ipt ip;
715
716 char * data = buf; // Keep a copy of the originals.
717 int size = len;
718
719 u8 b[MAXETHER + 20];
720
721 CSTAT(call_processipout);
722
723 if (len < MIN_IP_SIZE)
724 {
725 log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
726 STAT(tunnel_tx_errors);
727 return;
728 }
729 if (len >= MAXETHER)
730 {
731 log(1, 0, 0, 0, "Oversize IP packet %d bytes\n", len);
732 STAT(tunnel_tx_errors);
733 return;
734 }
735
736 // Skip the tun header
737 buf += 4;
738 len -= 4;
739
740 // Got an IP header now
741 if (*(u8 *)(buf) >> 4 != 4)
742 {
743 log(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
744 return;
745 }
746
747 ip = *(u32 *)(buf + 16);
748 if (!(s = sessionbyip(ip)))
749 {
750 // Is this a packet for a session that doesn't exist?
751 static int rate = 0; // Number of ICMP packets we've sent this second.
752 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
753
754 if (last != time_now)
755 {
756 last = time_now;
757 rate = 0;
758 }
759
760 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
761 {
762 log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
763 host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
764 }
765 return;
766 }
767 t = session[s].tunnel;
768 sp = &session[s];
769
770 if (sp->tbf_out)
771 {
772 // Are we throttling this session?
773 if (config->cluster_iam_master)
774 tbf_queue_packet(sp->tbf_out, data, size);
775 else
776 master_throttle_packet(sp->tbf_out, data, size);
777 return;
778 }
779 else if (sp->walled_garden && !config->cluster_iam_master)
780 {
781 // We are walled-gardening this
782 master_garden_packet(s, data, size);
783 return;
784 }
785
786 // Snooping this session, send it to intercept box
787 if (sp->snoop_ip && sp->snoop_port)
788 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
789
790 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
791
792 // Add on L2TP header
793 {
794 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
795 if (!p)
796 {
797 log(3, session[s].ip, s, t, "failed to send packet in processipout.\n");
798 return;
799 }
800 tunnelsend(b, len + (p-b), t); // send it...
801 }
802
803 sp->cout += len; // byte count
804 sp->total_cout += len; // byte count
805 sp->pout++;
806 udp_tx += len;
807 sess_count[s].cout += len; // To send to master..
808 }
809
810 //
811 // Helper routine for the TBF filters.
812 // Used to send queued data in to the user!
813 //
814 void send_ipout(sessionidt s, u8 *buf, int len)
815 {
816 sessiont *sp;
817 tunnelidt t;
818 ipt ip;
819
820 u8 b[MAXETHER + 20];
821
822 if (len < 0 || len > MAXETHER)
823 {
824 log(1,0,0,0, "Odd size IP packet: %d bytes\n", len);
825 return;
826 }
827
828 // Skip the tun header
829 buf += 4;
830 len -= 4;
831
832 ip = *(u32 *)(buf + 16);
833
834 if (!session[s].ip)
835 return;
836 t = session[s].tunnel;
837 sp = &session[s];
838
839 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
840
841 // Snooping this session.
842 if (sp->snoop_ip && sp->snoop_port)
843 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
844
845 // Add on L2TP header
846 {
847 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
848 if (!p)
849 {
850 log(3, session[s].ip, s, t, "failed to send packet in send_ipout.\n");
851 return;
852 }
853 tunnelsend(b, len + (p-b), t); // send it...
854 }
855 sp->cout += len; // byte count
856 sp->total_cout += len; // byte count
857 sp->pout++;
858 udp_tx += len;
859 sess_count[s].cout += len; // To send to master..
860 }
861
862 // add an AVP (16 bit)
863 void control16(controlt * c, u16 avp, u16 val, u8 m)
864 {
865 u16 l = (m ? 0x8008 : 0x0008);
866 *(u16 *) (c->buf + c->length + 0) = htons(l);
867 *(u16 *) (c->buf + c->length + 2) = htons(0);
868 *(u16 *) (c->buf + c->length + 4) = htons(avp);
869 *(u16 *) (c->buf + c->length + 6) = htons(val);
870 c->length += 8;
871 }
872
873 // add an AVP (32 bit)
874 void control32(controlt * c, u16 avp, u32 val, u8 m)
875 {
876 u16 l = (m ? 0x800A : 0x000A);
877 *(u16 *) (c->buf + c->length + 0) = htons(l);
878 *(u16 *) (c->buf + c->length + 2) = htons(0);
879 *(u16 *) (c->buf + c->length + 4) = htons(avp);
880 *(u32 *) (c->buf + c->length + 6) = htonl(val);
881 c->length += 10;
882 }
883
884 // add an AVP (32 bit)
885 void controls(controlt * c, u16 avp, char *val, u8 m)
886 {
887 u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
888 *(u16 *) (c->buf + c->length + 0) = htons(l);
889 *(u16 *) (c->buf + c->length + 2) = htons(0);
890 *(u16 *) (c->buf + c->length + 4) = htons(avp);
891 memcpy(c->buf + c->length + 6, val, strlen(val));
892 c->length += 6 + strlen(val);
893 }
894
895 // add a binary AVP
896 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
897 {
898 u16 l = ((m ? 0x8000 : 0) + len + 6);
899 *(u16 *) (c->buf + c->length + 0) = htons(l);
900 *(u16 *) (c->buf + c->length + 2) = htons(0);
901 *(u16 *) (c->buf + c->length + 4) = htons(avp);
902 memcpy(c->buf + c->length + 6, val, len);
903 c->length += 6 + len;
904 }
905
906 // new control connection
907 controlt *controlnew(u16 mtype)
908 {
909 controlt *c;
910 if (!controlfree)
911 c = malloc(sizeof(controlt));
912 else
913 {
914 c = controlfree;
915 controlfree = c->next;
916 }
917 assert(c);
918 c->next = 0;
919 *(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
920 c->length = 12;
921 control16(c, 0, mtype, 1);
922 return c;
923 }
924
925 // send zero block if nothing is waiting
926 // (ZLB send).
927 void controlnull(tunnelidt t)
928 {
929 u8 buf[12];
930 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
931 return;
932
933 *(u16 *) (buf + 0) = htons(0xC802); // flags/ver
934 *(u16 *) (buf + 2) = htons(12); // length
935 *(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
936 *(u16 *) (buf + 6) = htons(0); // session
937 *(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
938 *(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
939 tunnelsend(buf, 12, t);
940 }
941
942 // add a control message to a tunnel, and send if within window
943 void controladd(controlt * c, tunnelidt t, sessionidt s)
944 {
945 *(u16 *) (c->buf + 2) = htons(c->length); // length
946 *(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
947 *(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
948 *(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
949 tunnel[t].ns++; // advance sequence
950 // link in message in to queue
951 if (tunnel[t].controlc)
952 tunnel[t].controle->next = c;
953 else
954 tunnel[t].controls = c;
955 tunnel[t].controle = c;
956 tunnel[t].controlc++;
957 // send now if space in window
958 if (tunnel[t].controlc <= tunnel[t].window)
959 {
960 tunnel[t].try = 0; // first send
961 tunnelsend(c->buf, c->length, t);
962 }
963 }
964
965 //
966 // Throttle or Unthrottle a session
967 //
968 // Throttle the data folling through a session
969 // to be no more than 'throttle' kbit/sec each way.
970 //
971 int throttle_session(sessionidt s, int throttle)
972 {
973 if (!session[s].tunnel)
974 return 0; // No-one home.
975
976 if (!*session[s].user)
977 return 0; // User not logged in
978
979 if (throttle)
980 {
981 if (session[s].tbf_in || session[s].tbf_out)
982 {
983 if (throttle == session[s].throttle)
984 return 1;
985
986 // Currently throttled but the rate is changing.
987
988 free_tbf(session[s].tbf_in);
989 free_tbf(session[s].tbf_out);
990 }
991
992 session[s].tbf_in = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipin);
993 session[s].tbf_out = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipout);
994
995 if (throttle != session[s].throttle)
996 {
997 // Changed. Flood to slaves.
998 session[s].throttle = throttle;
999 cluster_send_session(s);
1000 }
1001
1002 return 1;
1003 }
1004
1005 // else Unthrottling.
1006
1007 if (!session[s].tbf_in && !session[s].tbf_out && !session[s].throttle)
1008 return 0;
1009
1010 free_tbf(session[s].tbf_in);
1011 session[s].tbf_in = 0;
1012
1013 free_tbf(session[s].tbf_out);
1014 session[s].tbf_out = 0;
1015
1016 if (throttle != session[s].throttle)
1017 {
1018 // Changed. Flood to slaves.
1019 session[s].throttle = throttle;
1020 cluster_send_session(s);
1021 }
1022
1023 return 0;
1024 }
1025
1026 // start tidy shutdown of session
1027 void sessionshutdown(sessionidt s, char *reason)
1028 {
1029 int dead = session[s].die;
1030 int walled_garden = session[s].walled_garden;
1031
1032
1033 CSTAT(call_sessionshutdown);
1034
1035 if (!session[s].tunnel)
1036 {
1037 log(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1038 return; // not a live session
1039 }
1040
1041 if (!dead)
1042 log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1043
1044 session[s].die = now() + 150; // Clean up in 15 seconds
1045
1046 {
1047 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1048 run_plugins(PLUGIN_KILL_SESSION, &data);
1049 }
1050
1051 // RADIUS Stop message
1052 if (session[s].opened && !walled_garden && !dead)
1053 {
1054 u16 r = session[s].radius;
1055 if (!r)
1056 {
1057 if (!(r = radiusnew(s)))
1058 {
1059 log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1060 STAT(radius_overflow);
1061 }
1062 else
1063 {
1064 int n;
1065 for (n = 0; n < 15; n++)
1066 radius[r].auth[n] = rand();
1067 }
1068 }
1069 if (r && radius[r].state != RADIUSSTOP)
1070 radiussend(r, RADIUSSTOP); // stop, if not already trying
1071 }
1072
1073 if (session[s].ip)
1074 { // IP allocated, clear and unroute
1075 int r;
1076 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1077 {
1078 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 0);
1079 session[s].route[r].ip = 0;
1080 }
1081
1082 if (session[s].ip_pool_index == -1) // static ip
1083 {
1084 routeset(s, session[s].ip, 0, 0, 0); // Delete route.
1085 session[s].ip = 0;
1086 }
1087 else
1088 free_ip_address(s);
1089
1090 if (session[s].throttle) // Unthrottle if throttled.
1091 throttle_session(s, 0);
1092 }
1093 { // Send CDN
1094 controlt *c = controlnew(14); // sending CDN
1095 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1096 control16(c, 14, s, 1); // assigned session (our end)
1097 controladd(c, session[s].tunnel, s); // send the message
1098 }
1099 cluster_send_session(s);
1100 }
1101
1102 void sendipcp(tunnelidt t, sessionidt s)
1103 {
1104 u8 buf[MAXCONTROL];
1105 u16 r = session[s].radius;
1106 u8 *q;
1107
1108 CSTAT(call_sendipcp);
1109
1110 if (!r)
1111 r = radiusnew(s);
1112
1113 if (radius[r].state != RADIUSIPCP)
1114 {
1115 radius[r].state = RADIUSIPCP;
1116 radius[r].try = 0;
1117 }
1118
1119 radius[r].retry = backoff(radius[r].try++);
1120 if (radius[r].try > 10)
1121 {
1122 radiusclear(r, s); // Clear radius session.
1123 sessionshutdown(s, "No reply on IPCP");
1124 return;
1125 }
1126
1127 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1128 if (!q)
1129 {
1130 log(3, session[s].ip, s, t, "failed to send packet in sendipcp.\n");
1131 return;
1132 }
1133
1134 *q = ConfigReq;
1135 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1136 *(u16 *) (q + 2) = htons(10);
1137 q[4] = 3;
1138 q[5] = 6;
1139 *(u32 *) (q + 6) = config->bind_address ? config->bind_address : my_address; // send my IP
1140 tunnelsend(buf, 10 + (q - buf), t); // send it
1141 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1142 }
1143
1144 // kill a session now
1145 void sessionkill(sessionidt s, char *reason)
1146 {
1147
1148 CSTAT(call_sessionkill);
1149
1150 session[s].die = now();
1151 sessionshutdown(s, reason); // close radius/routes, etc.
1152 if (session[s].radius)
1153 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1154
1155 log(2, 0, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1156
1157 throttle_session(s, 0); // Force session to be un-throttle. Free'ing TBF structures.
1158
1159 memset(&session[s], 0, sizeof(session[s]));
1160 session[s].tunnel = T_FREE; // Mark it as free.
1161 session[s].next = sessionfree;
1162 sessionfree = s;
1163 cli_session_actions[s].action = 0;
1164 cluster_send_session(s);
1165 }
1166
1167 // kill a tunnel now
1168 void tunnelkill(tunnelidt t, char *reason)
1169 {
1170 sessionidt s;
1171 controlt *c;
1172
1173 CSTAT(call_tunnelkill);
1174
1175 tunnel[t].state = TUNNELDIE;
1176
1177 // free control messages
1178 while ((c = tunnel[t].controls))
1179 {
1180 controlt * n = c->next;
1181 tunnel[t].controls = n;
1182 tunnel[t].controlc--;
1183 c->next = controlfree;
1184 controlfree = c;
1185 }
1186 // kill sessions
1187 for (s = 1; s < MAXSESSION; s++)
1188 if (session[s].tunnel == t)
1189 sessionkill(s, reason);
1190
1191 // free tunnel
1192 tunnelclear(t);
1193 log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
1194 cli_tunnel_actions[s].action = 0;
1195 cluster_send_tunnel(t);
1196 }
1197
1198 // shut down a tunnel cleanly
1199 void tunnelshutdown(tunnelidt t, char *reason)
1200 {
1201 sessionidt s;
1202
1203 CSTAT(call_tunnelshutdown);
1204
1205 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1206 {
1207 // never set up, can immediately kill
1208 tunnelkill(t, reason);
1209 return;
1210 }
1211 log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1212
1213 // close session
1214 for (s = 1; s < MAXSESSION; s++)
1215 if (session[s].tunnel == t)
1216 sessionkill(s, reason);
1217
1218 tunnel[t].state = TUNNELDIE;
1219 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1220 cluster_send_tunnel(t);
1221 // TBA - should we wait for sessions to stop?
1222 { // Send StopCCN
1223 controlt *c = controlnew(4); // sending StopCCN
1224 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message
1225 control16(c, 9, t, 1); // assigned tunnel (our end)
1226 controladd(c, t, 0); // send the message
1227 }
1228 }
1229
1230 // read and process packet on tunnel (UDP)
1231 void processudp(u8 * buf, int len, struct sockaddr_in *addr)
1232 {
1233 char *chapresponse = NULL;
1234 u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
1235 u8 *p = buf + 2;
1236
1237
1238 CSTAT(call_processudp);
1239
1240 udp_rx += len;
1241 udp_rx_pkt++;
1242 log_hex(5, "UDP Data", buf, len);
1243 STAT(tunnel_rx_packets);
1244 INC_STAT(tunnel_rx_bytes, len);
1245 if (len < 6)
1246 {
1247 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
1248 STAT(tunnel_rx_errors);
1249 return;
1250 }
1251 if ((buf[1] & 0x0F) != 2)
1252 {
1253 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1254 STAT(tunnel_rx_errors);
1255 return;
1256 }
1257 if (*buf & 0x40)
1258 { // length
1259 l = ntohs(*(u16 *) p);
1260 p += 2;
1261 }
1262 t = ntohs(*(u16 *) p);
1263 p += 2;
1264 s = ntohs(*(u16 *) p);
1265 p += 2;
1266 if (s >= MAXSESSION)
1267 {
1268 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
1269 STAT(tunnel_rx_errors);
1270 return;
1271 }
1272 if (t >= MAXTUNNEL)
1273 {
1274 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
1275 STAT(tunnel_rx_errors);
1276 return;
1277 }
1278 if (*buf & 0x08)
1279 { // ns/nr
1280 ns = ntohs(*(u16 *) p);
1281 p += 2;
1282 nr = ntohs(*(u16 *) p);
1283 p += 2;
1284 }
1285 if (*buf & 0x02)
1286 { // offset
1287 u16 o = ntohs(*(u16 *) p);
1288 p += o + 2;
1289 }
1290 if ((p - buf) > l)
1291 {
1292 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
1293 STAT(tunnel_rx_errors);
1294 return;
1295 }
1296 l -= (p - buf);
1297 if (*buf & 0x80)
1298 { // control
1299 u16 message = 0xFFFF; // message type
1300 u8 fatal = 0;
1301 u8 mandatorymessage = 0;
1302 u8 chap = 0; // if CHAP being used
1303 u16 asession = 0; // assigned session
1304 u32 amagic = 0; // magic number
1305 u8 aflags = 0; // flags from last LCF
1306 u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1307 int requestchap = 0; // do we request PAP instead of original CHAP request?
1308 char called[MAXTEL] = ""; // called number
1309 char calling[MAXTEL] = ""; // calling number
1310
1311 if (!config->cluster_iam_master)
1312 {
1313 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1314 return;
1315 }
1316
1317 if ((*buf & 0xCA) != 0xC8)
1318 {
1319 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
1320 STAT(tunnel_rx_errors);
1321 return;
1322 }
1323 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1324 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1325 // if no tunnel specified, assign one
1326 if (!t)
1327 {
1328 int i;
1329
1330 //
1331 // Is this a duplicate of the first packet? (SCCRQ)
1332 //
1333 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1334 {
1335 if (tunnel[i].state != TUNNELOPENING ||
1336 tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
1337 tunnel[i].port != ntohs(addr->sin_port) )
1338 continue;
1339 t = i;
1340 break;
1341 }
1342 }
1343
1344 if (!t)
1345 {
1346 if (!(t = new_tunnel()))
1347 {
1348 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
1349 STAT(tunnel_overflow);
1350 return;
1351 }
1352 tunnelclear(t);
1353 tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
1354 tunnel[t].port = ntohs(addr->sin_port);
1355 tunnel[t].window = 4; // default window
1356 log(1, ntohl(addr->sin_addr.s_addr), 0, t, " New tunnel from %u.%u.%u.%u/%u ID %d\n", tunnel[t].ip >> 24, tunnel[t].ip >> 16 & 255, tunnel[t].ip >> 8 & 255, tunnel[t].ip & 255, tunnel[t].port, t);
1357 STAT(tunnel_created);
1358 }
1359
1360 // This is used to time out old tunnels
1361 tunnel[t].lastrec = time_now;
1362
1363 // check sequence of this message
1364 {
1365 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1366 // some to clear maybe?
1367 while (tunnel[t].controlc && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1368 {
1369 controlt *c = tunnel[t].controls;
1370 tunnel[t].controls = c->next;
1371 tunnel[t].controlc--;
1372 c->next = controlfree;
1373 controlfree = c;
1374 skip--;
1375 tunnel[t].try = 0; // we have progress
1376 }
1377
1378 // If the 'ns' just received is not the 'nr' we're
1379 // expecting, just send an ack and drop it.
1380 //
1381 // if 'ns' is less, then we got a retransmitted packet.
1382 // if 'ns' is greater than missed a packet. Either way
1383 // we should ignore it.
1384 if (ns != tunnel[t].nr)
1385 {
1386 // is this the sequence we were expecting?
1387 log(1, ntohl(addr->sin_addr.s_addr), 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n", t, ns, tunnel[t].nr);
1388 STAT(tunnel_rx_errors);
1389
1390 if (l) // Is this not a ZLB?
1391 controlnull(t);
1392 return;
1393 }
1394 // receiver advance (do here so quoted correctly in any sends below)
1395 if (l) tunnel[t].nr = (ns + 1);
1396 if (skip < 0) skip = 0;
1397 if (skip < tunnel[t].controlc)
1398 {
1399 // some control packets can now be sent that were previous stuck out of window
1400 int tosend = tunnel[t].window - skip;
1401 controlt *c = tunnel[t].controls;
1402 while (c && skip)
1403 {
1404 c = c->next;
1405 skip--;
1406 }
1407 while (c && tosend)
1408 {
1409 tunnel[t].try = 0; // first send
1410 tunnelsend(c->buf, c->length, t);
1411 c = c->next;
1412 tosend--;
1413 }
1414 }
1415 if (!tunnel[t].controlc)
1416 tunnel[t].retry = 0; // caught up
1417 }
1418 if (l)
1419 { // if not a null message
1420 // process AVPs
1421 while (l && !(fatal & 0x80))
1422 {
1423 u16 n = (ntohs(*(u16 *) p) & 0x3FF);
1424 u8 *b = p;
1425 u8 flags = *p;
1426 u16 mtype;
1427 p += n; // next
1428 if (l < n)
1429 {
1430 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
1431 STAT(tunnel_rx_errors);
1432 fatal = flags;
1433 return;
1434 }
1435 l -= n;
1436 if (flags & 0x40)
1437 {
1438 // handle hidden AVPs
1439 if (!*config->l2tpsecret)
1440 {
1441 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
1442 fatal = flags;
1443 continue;
1444 }
1445 if (!session[s].random_vector_length)
1446 {
1447 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
1448 fatal = flags;
1449 continue;
1450 }
1451 log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
1452 }
1453 if (*b & 0x3C)
1454 {
1455 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
1456 fatal = flags;
1457 continue; // next
1458 }
1459 b += 2;
1460 if (*(u16 *) (b))
1461 {
1462 log(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
1463 fatal = flags;
1464 continue; // next
1465 }
1466 b += 2;
1467 mtype = ntohs(*(u16 *) (b));
1468 b += 2;
1469 n -= 6;
1470
1471 log(4, ntohl(addr->sin_addr.s_addr), s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1472 switch (mtype)
1473 {
1474 case 0: // message type
1475 message = ntohs(*(u16 *) b);
1476 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Message type = %d (%s)\n", *b,
1477 l2tp_message_types[message]);
1478 mandatorymessage = flags;
1479 break;
1480 case 1: // result code
1481 {
1482 u16 rescode = ntohs(*(u16 *)(b));
1483 const char* resdesc = "(unknown)";
1484 if (message == 4)
1485 { /* StopCCN */
1486 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1487 resdesc = stopccn_result_codes[rescode];
1488 }
1489 else if (message == 14)
1490 { /* CDN */
1491 if (rescode <= MAX_CDN_RESULT_CODE)
1492 resdesc = cdn_result_codes[rescode];
1493 }
1494
1495 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Result Code %d: %s\n",
1496 rescode, resdesc);
1497 if (n >= 4)
1498 {
1499 u16 errcode = ntohs(*(u16 *)(b + 2));
1500 const char* errdesc = "(unknown)";
1501 if (errcode <= MAX_ERROR_CODE)
1502 errdesc = error_codes[errcode];
1503 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error Code %d: %s\n",
1504 errcode, errdesc);
1505 }
1506 if (n > 4)
1507 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error String: %.*s\n",
1508 n-4, b+4);
1509
1510 break;
1511 }
1512 break;
1513 case 2: // protocol version
1514 {
1515 version = ntohs(*(u16 *) (b));
1516 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Protocol version = %d\n", version);
1517 if (version && version != 0x0100)
1518 { // allow 0.0 and 1.0
1519 log(1, ntohl(addr->sin_addr.s_addr), s, t, " Bad protocol version %04X\n",
1520 version);
1521 fatal = flags;
1522 continue; // next
1523 }
1524 }
1525 break;
1526 case 3: // framing capabilities
1527 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
1528 break;
1529 case 4: // bearer capabilities
1530 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
1531 break;
1532 case 5: // tie breaker
1533 // We never open tunnels, so we don't care about tie breakers
1534 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
1535 continue;
1536 case 6: // firmware revision
1537 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
1538 break;
1539 case 7: // host name
1540 memset(tunnel[t].hostname, 0, 128);
1541 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1542 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1543 // TBA - to send to RADIUS
1544 break;
1545 case 8: // vendor name
1546 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1547 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1548 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1549 break;
1550 case 9: // assigned tunnel
1551 tunnel[t].far = ntohs(*(u16 *) (b));
1552 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1553 break;
1554 case 10: // rx window
1555 tunnel[t].window = ntohs(*(u16 *) (b));
1556 if (!tunnel[t].window)
1557 tunnel[t].window = 1; // window of 0 is silly
1558 log(4, ntohl(addr->sin_addr.s_addr), s, t, " rx window = %d\n", tunnel[t].window);
1559 break;
1560 case 11: // Challenge
1561 {
1562 log(4, ntohl(addr->sin_addr.s_addr), s, t, " LAC requested CHAP authentication for tunnel\n");
1563 build_chap_response(b, 2, n, &chapresponse);
1564 }
1565 break;
1566 case 14: // assigned session
1567 asession = session[s].far = ntohs(*(u16 *) (b));
1568 log(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
1569 break;
1570 case 15: // call serial number
1571 log(4, ntohl(addr->sin_addr.s_addr), s, t, " call serial number = %d\n", ntohl(*(u32 *)b));
1572 break;
1573 case 18: // bearer type
1574 log(4, ntohl(addr->sin_addr.s_addr), s, t, " bearer type = %d\n", ntohl(*(u32 *)b));
1575 // TBA - for RADIUS
1576 break;
1577 case 19: // framing type
1578 log(4, ntohl(addr->sin_addr.s_addr), s, t, " framing type = %d\n", ntohl(*(u32 *)b));
1579 // TBA
1580 break;
1581 case 21: // called number
1582 memset(called, 0, MAXTEL);
1583 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1584 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Called <%s>\n", called);
1585 break;
1586 case 22: // calling number
1587 memset(calling, 0, MAXTEL);
1588 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1589 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Calling <%s>\n", calling);
1590 break;
1591 case 23: // subtype
1592 break;
1593 case 24: // tx connect speed
1594 if (n == 4)
1595 {
1596 session[s].tx_connect_speed = ntohl(*(u32 *)b);
1597 }
1598 else
1599 {
1600 // AS5300s send connect speed as a string
1601 char tmp[30] = {0};
1602 memcpy(tmp, b, (n >= 30) ? 30 : n);
1603 session[s].tx_connect_speed = atol(tmp);
1604 }
1605 log(4, ntohl(addr->sin_addr.s_addr), s, t, " TX connect speed <%u>\n",
1606 session[s].tx_connect_speed);
1607 break;
1608 case 38: // rx connect speed
1609 if (n == 4)
1610 {
1611 session[s].rx_connect_speed = ntohl(*(u32 *)b);
1612 }
1613 else
1614 {
1615 // AS5300s send connect speed as a string
1616 char tmp[30] = {0};
1617 memcpy(tmp, b, (n >= 30) ? 30 : n);
1618 session[s].rx_connect_speed = atol(tmp);
1619 }
1620 log(4, ntohl(addr->sin_addr.s_addr), s, t, " RX connect speed <%u>\n",
1621 session[s].rx_connect_speed);
1622 break;
1623 case 25: // Physical Channel ID
1624 {
1625 u32 tmp = ntohl(*(u32 *)b);
1626 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Physical Channel ID <%X>\n", tmp);
1627 break;
1628 }
1629 case 29: // Proxy Authentication Type
1630 {
1631 u16 authtype = ntohs(*(u16 *)b);
1632 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Type %d (%s)\n",
1633 authtype, authtypes[authtype]);
1634 requestchap = (authtype == 2);
1635 break;
1636 }
1637 case 30: // Proxy Authentication Name
1638 {
1639 char authname[64] = {0};
1640 memcpy(authname, b, (n > 63) ? 63 : n);
1641 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Name (%s)\n",
1642 authname);
1643 break;
1644 }
1645 case 31: // Proxy Authentication Challenge
1646 {
1647 memcpy(radius[session[s].radius].auth, b, 16);
1648 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Challenge\n");
1649 break;
1650 }
1651 case 32: // Proxy Authentication ID
1652 {
1653 u16 authid = ntohs(*(u16 *)(b));
1654 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth ID (%d)\n",
1655 authid);
1656 if (session[s].radius)
1657 radius[session[s].radius].id = authid;
1658 break;
1659 }
1660 case 33: // Proxy Authentication Response
1661 {
1662 char authresp[64] = {0};
1663 memcpy(authresp, b, (n > 63) ? 63 : n);
1664 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Response\n");
1665 break;
1666 }
1667 case 27: // last send lcp
1668 { // find magic number
1669 u8 *p = b, *e = p + n;
1670 while (p < e && p[1])
1671 {
1672 if (*p == 5 && p[1] == 6)
1673 amagic = ntohl(*(u32 *) (p + 2));
1674 else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5)
1675 chap = 1;
1676 else if (*p == 7)
1677 aflags |= SESSIONPFC;
1678 else if (*p == 8)
1679 aflags |= SESSIONACFC;
1680 p += p[1];
1681 }
1682
1683 {
1684 char tmp[500] = {0};
1685 tmp[0] = ConfigReq;
1686 memcpy((tmp + 1), b, n);
1687 }
1688 }
1689 break;
1690 case 28: // last recv lcp confreq
1691 {
1692 char tmp[500] = {0};
1693 tmp[0] = ConfigReq;
1694 memcpy((tmp + 1), b, n);
1695 break;
1696 }
1697 case 26: // Initial Received LCP CONFREQ
1698 {
1699 char tmp[500] = {0};
1700 tmp[0] = ConfigReq;
1701 memcpy((tmp + 1), b, n);
1702 }
1703 break;
1704 case 39: // seq required - we control it as an LNS anyway...
1705 break;
1706 case 36: // Random Vector
1707 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Random Vector received. Enabled AVP Hiding.\n");
1708 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1709 memcpy(session[s].random_vector, b, n);
1710 session[s].random_vector_length = n;
1711 break;
1712 default:
1713 log(2, ntohl(addr->sin_addr.s_addr), s, t, " Unknown AVP type %d\n", mtype);
1714 fatal = flags;
1715 continue; // next
1716 }
1717 }
1718 // process message
1719 if (fatal & 0x80)
1720 tunnelshutdown(t, "Unknown Mandatory AVP");
1721 else
1722 switch (message)
1723 {
1724 case 1: // SCCRQ - Start Control Connection Request
1725 {
1726 controlt *c = controlnew(2); // sending SCCRP
1727 control16(c, 2, version, 1); // protocol version
1728 control32(c, 3, 3, 1); // framing
1729 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1730 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1731 control16(c, 9, t, 1); // assigned tunnel
1732 controladd(c, t, s); // send the resply
1733 }
1734 tunnel[t].state = TUNNELOPENING;
1735 break;
1736 case 2: // SCCRP
1737 tunnel[t].state = TUNNELOPEN;
1738 break;
1739 case 3: // SCCN
1740 tunnel[t].state = TUNNELOPEN;
1741 controlnull(t); // ack
1742 break;
1743 case 4: // StopCCN
1744 controlnull(t); // ack
1745 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1746 tunnelkill(t, "Stopped"); // Immediately force everything dead
1747 break;
1748 case 6: // HELLO
1749 controlnull(t); // simply ACK
1750 break;
1751 case 7: // OCRQ
1752 // TBA
1753 break;
1754 case 8: // OCRO
1755 // TBA
1756 break;
1757 case 9: // OCCN
1758 // TBA
1759 break;
1760 case 10: // ICRQ
1761 if (!sessionfree)
1762 {
1763 STAT(session_overflow);
1764 tunnelshutdown(t, "No free sessions");
1765 }
1766 else
1767 {
1768 u16 r;
1769 controlt *c;
1770
1771 s = sessionfree;
1772 sessionfree = session[s].next;
1773 memset(&session[s], 0, sizeof(session[s]));
1774
1775 if (s > config->cluster_highest_sessionid)
1776 config->cluster_highest_sessionid = s;
1777
1778 // make a RADIUS session
1779 if (!(r = radiusnew(s)))
1780 {
1781 log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
1782 sessionkill(s, "no free RADIUS sesions");
1783 return;
1784 }
1785
1786 c = controlnew(11); // sending ICRP
1787 session[s].id = sessionid++;
1788 session[s].opened = time(NULL);
1789 session[s].tunnel = t;
1790 session[s].far = asession;
1791 session[s].last_packet = time_now;
1792 log(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1793 control16(c, 14, s, 1); // assigned session
1794 controladd(c, t, s); // send the reply
1795 {
1796 // Generate a random challenge
1797 int n;
1798 for (n = 0; n < 15; n++)
1799 radius[r].auth[n] = rand();
1800 }
1801 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1802 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1803 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1804 STAT(session_created);
1805 }
1806 break;
1807 case 11: // ICRP
1808 // TBA
1809 break;
1810 case 12: // ICCN
1811 if ( amagic == 0) amagic = time_now;
1812 session[s].magic = amagic; // set magic number
1813 session[s].l2tp_flags = aflags; // set flags received
1814 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
1815 controlnull(t); // ack
1816 // In CHAP state, request PAP instead
1817 if (requestchap)
1818 initlcp(t, s);
1819 break;
1820 case 14: // CDN
1821 controlnull(t); // ack
1822 sessionshutdown(s, "Closed (Received CDN)");
1823 break;
1824 case 0xFFFF:
1825 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
1826 break;
1827 default:
1828 STAT(tunnel_rx_errors);
1829 if (mandatorymessage & 0x80)
1830 tunnelshutdown(t, "Unknown message");
1831 else
1832 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
1833 break;
1834 }
1835 if (chapresponse) free(chapresponse);
1836 cluster_send_tunnel(t);
1837 }
1838 else
1839 {
1840 log(4, 0, s, t, " Got a ZLB ack\n");
1841 }
1842 }
1843 else
1844 { // data
1845 u16 prot;
1846
1847 log_hex(5, "Receive Tunnel Data", p, l);
1848 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1849 { // HDLC address header, discard
1850 p += 2;
1851 l -= 2;
1852 }
1853 if (l < 2)
1854 {
1855 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
1856 STAT(tunnel_rx_errors);
1857 return;
1858 }
1859 if (*p & 1)
1860 {
1861 prot = *p++;
1862 l--;
1863 }
1864 else
1865 {
1866 prot = ntohs(*(u16 *) p);
1867 p += 2;
1868 l -= 2;
1869 }
1870
1871 if (s && !session[s].tunnel) // Is something wrong??
1872 {
1873 if (!config->cluster_iam_master)
1874 {
1875 // Pass it off to the master to deal with..
1876 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1877 return;
1878 }
1879
1880
1881 log(1, ntohl(addr->sin_addr.s_addr), s, t, "UDP packet contains session %d "
1882 "but no session[%d].tunnel exists (LAC said"
1883 " tunnel = %d). Dropping packet.\n", s, s, t);
1884 STAT(tunnel_rx_errors);
1885 return;
1886 }
1887
1888 if (session[s].die)
1889 {
1890 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
1891 // I'm pretty sure this isn't right -- mo.
1892 // return; // closing session, PPP not processed
1893 }
1894 if (prot == PPPPAP)
1895 {
1896 session[s].last_packet = time_now;
1897 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1898 processpap(t, s, p, l);
1899 }
1900 else if (prot == PPPCHAP)
1901 {
1902 session[s].last_packet = time_now;
1903 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1904 processchap(t, s, p, l);
1905 }
1906 else if (prot == PPPLCP)
1907 {
1908 session[s].last_packet = time_now;
1909 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1910 processlcp(t, s, p, l);
1911 }
1912 else if (prot == PPPIPCP)
1913 {
1914 session[s].last_packet = time_now;
1915 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1916 processipcp(t, s, p, l);
1917 }
1918 else if (prot == PPPCCP)
1919 {
1920 session[s].last_packet = time_now;
1921 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1922 processccp(t, s, p, l);
1923 }
1924 else if (prot == PPPIP)
1925 {
1926 if (!config->cluster_iam_master)
1927 {
1928 // We're a slave. Should we forward this packet to the master?
1929
1930 // Is this a walled garden session, or something that needs it's
1931 // idle time updated??
1932
1933 // Maintain the idle timeouts on the master. If this would
1934 // significantly reset the idletimeout, run it via the master
1935 // to refresh the master's idle timer.
1936 // Not sure this is ideal: It may re-order packets.
1937
1938 if (session[s].walled_garden || (session[s].last_packet + (ECHO_TIMEOUT/2)) < time_now)
1939 {
1940 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1941 session[s].last_packet = time_now;
1942 return;
1943 }
1944 // fall through to processipin.
1945 } else
1946 session[s].last_packet = time_now;
1947 processipin(t, s, p, l);
1948 }
1949 else
1950 {
1951 STAT(tunnel_rx_errors);
1952 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
1953 }
1954 }
1955 }
1956
1957 // read and process packet on tun
1958 void processtun(u8 * buf, int len)
1959 {
1960 log_hex(5, "Receive TUN Data", buf, len);
1961 STAT(tun_rx_packets);
1962 INC_STAT(tun_rx_bytes, len);
1963
1964 CSTAT(call_processtun);
1965
1966 eth_rx_pkt++;
1967 eth_rx += len;
1968 if (len < 22)
1969 {
1970 log(1, 0, 0, 0, "Short tun packet %d bytes\n", len);
1971 STAT(tun_rx_errors);
1972 return;
1973 }
1974
1975 if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
1976 processipout(buf, len);
1977 // Else discard.
1978 }
1979
1980 //
1981 // Maximum number of actions to complete.
1982 // This is to avoid sending out too many packets
1983 // at once.
1984 #define MAX_ACTIONS 500
1985
1986 int regular_cleanups(void)
1987 {
1988 static sessionidt s = 0; // Next session to check for actions on.
1989 tunnelidt t;
1990 int count=0,i;
1991 u16 r;
1992 static clockt next_acct = 0;
1993 int a;
1994
1995 log(3, 0, 0, 0, "Begin regular cleanup\n");
1996
1997 for (r = 1; r < MAXRADIUS; r++)
1998 {
1999 if (!radius[r].state)
2000 continue;
2001 if (radius[r].retry)
2002 {
2003 if (radius[r].retry <= TIME)
2004 radiusretry(r);
2005 } else
2006 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2007 }
2008 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
2009 {
2010 // check for expired tunnels
2011 if (tunnel[t].die && tunnel[t].die <= TIME)
2012 {
2013 STAT(tunnel_timeout);
2014 tunnelkill(t, "Expired");
2015 continue;
2016 }
2017 // check for message resend
2018 if (tunnel[t].retry && tunnel[t].controlc)
2019 {
2020 // resend pending messages as timeout on reply
2021 if (tunnel[t].retry <= TIME)
2022 {
2023 controlt *c = tunnel[t].controls;
2024 u8 w = tunnel[t].window;
2025 tunnel[t].try++; // another try
2026 if (tunnel[t].try > 5)
2027 tunnelkill(t, "Timeout on control message"); // game over
2028 else
2029 while (c && w--)
2030 {
2031 tunnelsend(c->buf, c->length, t);
2032 c = c->next;
2033 }
2034 }
2035 }
2036 // Send hello
2037 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2038 {
2039 controlt *c = controlnew(6); // sending HELLO
2040 controladd(c, t, 0); // send the message
2041 log(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
2042 }
2043
2044 // Check for tunnel changes requested from the CLI
2045 if ((a = cli_tunnel_actions[t].action))
2046 {
2047 cli_tunnel_actions[t].action = 0;
2048 if (a & CLI_TUN_KILL)
2049 {
2050 log(2, tunnel[t].ip, 0, t, "Dropping tunnel by CLI\n");
2051 tunnelshutdown(t, "Requested by administrator");
2052 }
2053 }
2054
2055 }
2056
2057 count = 0;
2058 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2059 {
2060 s++;
2061 if (s > config->cluster_highest_sessionid)
2062 s = 1;
2063
2064 if (!session[s].tunnel) // Session isn't in use
2065 continue;
2066
2067 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2068 {
2069 // IPCP has not completed yet. Resend
2070 log(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2071 sendipcp(session[s].tunnel, s);
2072 }
2073
2074 // check for expired sessions
2075 if (session[s].die && session[s].die <= TIME)
2076 {
2077 sessionkill(s, "Expired");
2078 if (++count >= MAX_ACTIONS) break;
2079 continue;
2080 }
2081
2082 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2083 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2084 {
2085 sessionkill(s, "No response to LCP ECHO requests");
2086 STAT(session_timeout);
2087 if (++count >= MAX_ACTIONS) break;
2088 continue;
2089 }
2090
2091 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2092 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2093 {
2094 u8 b[MAXCONTROL] = {0};
2095
2096 u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2097 if (!q)
2098 {
2099 log(3, session[s].ip, s, t, "failed to send ECHO packet.\n");
2100 continue;
2101 }
2102
2103 *q = EchoReq;
2104 *(u8 *)(q + 1) = (time_now % 255); // ID
2105 *(u16 *)(q + 2) = htons(8); // Length
2106 *(u32 *)(q + 4) = 0; // Magic Number (not supported)
2107
2108 log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2109 (int)(time_now - session[s].last_packet));
2110 tunnelsend(b, 24, session[s].tunnel); // send it
2111 if (++count >= MAX_ACTIONS) break;
2112 }
2113
2114 // Check for actions requested from the CLI
2115 if ((a = cli_session_actions[s].action))
2116 {
2117 int send = 0;
2118
2119 cli_session_actions[s].action = 0;
2120 if (a & CLI_SESS_KILL)
2121 {
2122 log(2, 0, s, session[s].tunnel, "Dropping session by CLI\n");
2123 sessionshutdown(s, "Requested by administrator");
2124 a = 0; // dead, no need to check for other actions
2125 }
2126
2127 if (a & CLI_SESS_SNOOP)
2128 {
2129 log(2, 0, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2130 inet_toa(cli_session_actions[s].snoop_ip), cli_session_actions[s].snoop_port);
2131
2132 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2133 session[s].snoop_port = cli_session_actions[s].snoop_port;
2134 send++;
2135 }
2136
2137 if (a & CLI_SESS_NOSNOOP)
2138 {
2139 log(2, 0, s, session[s].tunnel, "Unsnooping session by CLI\n");
2140 session[s].snoop_ip = 0;
2141 session[s].snoop_port = 0;
2142 send++;
2143 }
2144
2145 if (a & CLI_SESS_THROTTLE)
2146 {
2147 log(2, 0, s, session[s].tunnel, "Throttling session by CLI (to %d)\n",
2148 cli_session_actions[s].throttle);
2149
2150 throttle_session(s, cli_session_actions[s].throttle);
2151 }
2152
2153 if (a & CLI_SESS_NOTHROTTLE)
2154 {
2155 log(2, 0, s, session[s].tunnel, "Un-throttling session by CLI\n");
2156 throttle_session(s, 0);
2157 }
2158
2159 if (send)
2160 cluster_send_session(s);
2161
2162 if (++count >= MAX_ACTIONS) break;
2163 }
2164 }
2165
2166 if (config->accounting_dir && next_acct <= TIME)
2167 {
2168 // Dump accounting data
2169 next_acct = TIME + ACCT_TIME;
2170 dump_acct_info();
2171 }
2172
2173 if (count >= MAX_ACTIONS)
2174 return 1; // Didn't finish!
2175
2176 log(3, 0, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2177 return 0;
2178 }
2179
2180
2181 //
2182 // Are we in the middle of a tunnel update, or radius
2183 // requests??
2184 //
2185 int still_busy(void)
2186 {
2187 int i;
2188 static clockt last_talked = 0;
2189 static clockt start_busy_wait = 0;
2190 if (start_busy_wait == 0)
2191 start_busy_wait = TIME;
2192
2193 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2194 {
2195 if (!tunnel[i].controlc)
2196 continue;
2197
2198 if (last_talked != TIME)
2199 {
2200 log(2,0,0,0, "Tunnel %d still has un-acked control messages.\n", i);
2201 last_talked = TIME;
2202 }
2203 return 1;
2204 }
2205
2206 // We stop waiting for radius after BUSY_WAIT_TIMEOUT 1/10th seconds
2207 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIMEOUT)
2208 {
2209 log(1, 0, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2210 return 0;
2211 }
2212
2213 for (i = 1; i < MAXRADIUS; i++)
2214 {
2215 if (radius[i].state == RADIUSNULL)
2216 continue;
2217 if (radius[i].state == RADIUSWAIT)
2218 continue;
2219
2220 if (last_talked != TIME)
2221 {
2222 log(2,0,0,0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2223 last_talked = TIME;
2224 }
2225 return 1;
2226 }
2227
2228 return 0;
2229 }
2230
2231 // main loop - gets packets on tun or udp and processes them
2232 void mainloop(void)
2233 {
2234 fd_set cr;
2235 int cn, i;
2236 u8 buf[65536];
2237 struct timeval to;
2238 clockt next_cluster_ping = 0; // send initial ping immediately
2239 time_t next_clean = time_now + config->cleanup_interval;
2240
2241 log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2242 udpfd, tunfd, cluster_sockfd, controlfd);
2243
2244 FD_ZERO(&cr);
2245 FD_SET(udpfd, &cr);
2246 FD_SET(tunfd, &cr);
2247 FD_SET(controlfd, &cr);
2248 FD_SET(clifd, &cr);
2249 if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
2250 cn = udpfd;
2251 if (cn < tunfd) cn = tunfd;
2252 if (cn < controlfd) cn = controlfd;
2253 if (cn < clifd) cn = clifd;
2254 if (cn < cluster_sockfd) cn = cluster_sockfd;
2255 for (i = 0; i < config->num_radfds; i++)
2256 {
2257 if (!radfds[i]) continue;
2258 FD_SET(radfds[i], &cr);
2259 if (radfds[i] > cn)
2260 cn = radfds[i];
2261 }
2262
2263 while (!main_quit || still_busy())
2264 {
2265 fd_set r;
2266 int n = cn;
2267 #ifdef BGP
2268 fd_set w;
2269 int bgp_set[BGP_NUM_PEERS];
2270 #endif /* BGP */
2271
2272 if (config->reload_config)
2273 {
2274 // Update the config state based on config settings
2275 update_config();
2276 }
2277
2278 memcpy(&r, &cr, sizeof(fd_set));
2279 to.tv_sec = 0;
2280 to.tv_usec = 100000; // 1/10th of a second.
2281
2282 #ifdef BGP
2283 FD_ZERO(&w);
2284 for (i = 0; i < BGP_NUM_PEERS; i++)
2285 {
2286 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2287 if (bgp_set[i] & 1)
2288 {
2289 FD_SET(bgp_peers[i].sock, &r);
2290 if (bgp_peers[i].sock > n)
2291 n = bgp_peers[i].sock;
2292 }
2293
2294 if (bgp_set[i] & 2)
2295 {
2296 FD_SET(bgp_peers[i].sock, &w);
2297 if (bgp_peers[i].sock > n)
2298 n = bgp_peers[i].sock;
2299 }
2300 }
2301
2302 n = select(n + 1, &r, &w, 0, &to);
2303 #else /* BGP */
2304 n = select(n + 1, &r, 0, 0, &to);
2305 #endif /* BGP */
2306
2307 TIME = now();
2308 if (n < 0)
2309 {
2310 if (errno == EINTR)
2311 continue;
2312
2313 log(0, 0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2314 main_quit++;
2315 break;
2316 }
2317 else if (n)
2318 {
2319 struct sockaddr_in addr;
2320 int alen = sizeof(addr);
2321 if (FD_ISSET(udpfd, &r))
2322 {
2323 int c, n;
2324 for (c = 0; c < config->multi_read_count; c++)
2325 {
2326 if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2327 processudp(buf, n, &addr);
2328 else
2329 break;
2330 }
2331 }
2332 if (FD_ISSET(tunfd, &r))
2333 {
2334 int c, n;
2335 for (c = 0; c < config->multi_read_count; c++)
2336 {
2337 if ((n = read(tunfd, buf, sizeof(buf))) > 0)
2338 processtun(buf, n);
2339 else
2340 break;
2341 }
2342 }
2343 for (i = 0; i < config->num_radfds; i++)
2344 if (FD_ISSET(radfds[i], &r))
2345 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2346 if (FD_ISSET(cluster_sockfd, &r))
2347 {
2348 int size;
2349 size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
2350 processcluster(buf, size, addr.sin_addr.s_addr);
2351 }
2352 if (FD_ISSET(controlfd, &r))
2353 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
2354 if (FD_ISSET(clifd, &r))
2355 {
2356 struct sockaddr_in addr;
2357 int sockfd;
2358 int len = sizeof(addr);
2359
2360 if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
2361 {
2362 log(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
2363 continue;
2364 }
2365 else
2366 {
2367 cli_do(sockfd);
2368 close(sockfd);
2369 }
2370 }
2371 }
2372
2373 // Runs on every machine (master and slaves).
2374 if (cluster_sockfd && next_cluster_ping <= TIME)
2375 {
2376 // Check to see which of the cluster is still alive..
2377
2378 cluster_send_ping(basetime); // Only does anything if we're a slave
2379 cluster_check_master(); // ditto.
2380
2381 cluster_heartbeat(); // Only does anything if we're a master.
2382 cluster_check_slaves(); // ditto.
2383
2384 master_update_counts(); // If we're a slave, send our byte counters to our master.
2385
2386 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2387 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2388 else
2389 next_cluster_ping = TIME + config->cluster_hb_interval;
2390 }
2391
2392 // Run token bucket filtering queue..
2393 // Only run it every 1/10th of a second.
2394 // Runs on all machines both master and slave.
2395 {
2396 static clockt last_run = 0;
2397 if (last_run != TIME)
2398 {
2399 last_run = TIME;
2400 tbf_run_timer();
2401 }
2402 }
2403
2404 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2405 * something to read, else under load this will never actually run....
2406 *
2407 */
2408 if (config->cluster_iam_master && next_clean <= time_now)
2409 {
2410 if (regular_cleanups())
2411 {
2412 // Did it finish?
2413 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2414 }
2415 else
2416 {
2417 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2418 }
2419 }
2420
2421 #ifdef BGP
2422 for (i = 0; i < BGP_NUM_PEERS; i++)
2423 {
2424 bgp_process(&bgp_peers[i],
2425 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
2426 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
2427 }
2428 #endif /* BGP */
2429 }
2430
2431 // Are we the master and shutting down??
2432 if (config->cluster_iam_master)
2433 cluster_heartbeat(); // Flush any queued changes..
2434
2435 // Ok. Notify everyone we're shutting down. If we're
2436 // the master, this will force an election.
2437 cluster_send_ping(0);
2438
2439 //
2440 // Important!!! We MUST not process any packets past this point!
2441 }
2442
2443 // Init data structures
2444 void initdata(void)
2445 {
2446 int i;
2447
2448 _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2449 if (_statistics == MAP_FAILED)
2450 {
2451 log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
2452 exit(1);
2453 }
2454 config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2455 if (config == MAP_FAILED)
2456 {
2457 log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
2458 exit(1);
2459 }
2460 memset(config, 0, sizeof(struct configt));
2461 time(&config->start_time);
2462 strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
2463 tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2464 if (tunnel == MAP_FAILED)
2465 {
2466 log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
2467 exit(1);
2468 }
2469 session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2470 if (session == MAP_FAILED)
2471 {
2472 log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
2473 exit(1);
2474 }
2475
2476 sess_count = mmap(NULL, sizeof(sessioncountt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2477 if (sess_count == MAP_FAILED)
2478 {
2479 log(0, 0, 0, 0, "Error doing mmap for sessions_count: %s\n", strerror(errno));
2480 exit(1);
2481 }
2482
2483 radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2484 if (radius == MAP_FAILED)
2485 {
2486 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2487 exit(1);
2488 }
2489 ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2490 if (ip_address_pool == MAP_FAILED)
2491 {
2492 log(0, 0, 0, 0, "Error doing mmap for ip_address_pool: %s\n", strerror(errno));
2493 exit(1);
2494 }
2495 #ifdef RINGBUFFER
2496 ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2497 if (ringbuffer == MAP_FAILED)
2498 {
2499 log(0, 0, 0, 0, "Error doing mmap for ringbuffer: %s\n", strerror(errno));
2500 exit(1);
2501 }
2502 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2503 #endif
2504
2505 cli_session_actions = mmap(NULL, sizeof(struct cli_session_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2506 if (cli_session_actions == MAP_FAILED)
2507 {
2508 log(0, 0, 0, 0, "Error doing mmap for cli session actions: %s\n", strerror(errno));
2509 exit(1);
2510 }
2511 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2512 cli_tunnel_actions = mmap(NULL, sizeof(struct cli_tunnel_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2513 if (cli_tunnel_actions == MAP_FAILED)
2514 {
2515 log(0, 0, 0, 0, "Error doing mmap for cli tunnel actions: %s\n", strerror(errno));
2516 exit(1);
2517 }
2518 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2519
2520 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2521 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2522 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2523 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2524
2525 // Put all the sessions on the free list marked as undefined.
2526 for (i = 1; i < MAXSESSION - 1; i++)
2527 {
2528 session[i].next = i + 1;
2529 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2530 }
2531 session[MAXSESSION - 1].next = 0;
2532 sessionfree = 1;
2533
2534 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2535 for (i = 1; i < MAXTUNNEL- 1; i++)
2536 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2537
2538 if (!*hostname)
2539 {
2540 char *p;
2541 // Grab my hostname unless it's been specified
2542 gethostname(hostname, sizeof(hostname));
2543 if ((p = strchr(hostname, '.'))) *p = 0;
2544 }
2545 _statistics->start_time = _statistics->last_reset = time(NULL);
2546
2547 #ifdef BGP
2548 bgp_peers = mmap(NULL, sizeof(struct bgp_peer) * BGP_NUM_PEERS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2549 if (bgp_peers == MAP_FAILED)
2550 {
2551 log(0, 0, 0, 0, "Error doing mmap for bgp: %s\n", strerror(errno));
2552 exit(1);
2553 }
2554 #endif /* BGP */
2555 }
2556
2557 void initiptables(void)
2558 {
2559 /* Flush the tables here so that we have a clean slate */
2560
2561 // Not needed. 'nat' is setup by garden.c
2562 // mangle isn't used (as throttling is done by tbf inhouse).
2563 }
2564
2565 int assign_ip_address(sessionidt s)
2566 {
2567 u32 i;
2568 int best = -1;
2569 time_t best_time = time_now;
2570 char *u = session[s].user;
2571 char reuse = 0;
2572
2573
2574 CSTAT(call_assign_ip_address);
2575
2576 for (i = 1; i < ip_pool_size; i++)
2577 {
2578 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2579 continue;
2580
2581 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2582 {
2583 best = i;
2584 reuse = 1;
2585 break;
2586 }
2587
2588 if (ip_address_pool[i].last < best_time)
2589 {
2590 best = i;
2591 if (!(best_time = ip_address_pool[i].last))
2592 break; // never used, grab this one
2593 }
2594 }
2595
2596 if (best < 0)
2597 {
2598 log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2599 return 0;
2600 }
2601
2602 session[s].ip = ip_address_pool[best].address;
2603 session[s].ip_pool_index = best;
2604 ip_address_pool[best].assigned = 1;
2605 ip_address_pool[best].last = time_now;
2606 ip_address_pool[best].session = s;
2607 if (session[s].walled_garden)
2608 /* Don't track addresses of users in walled garden (note: this
2609 means that their address isn't "sticky" even if they get
2610 un-gardened). */
2611 ip_address_pool[best].user[0] = 0;
2612 else
2613 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2614
2615 STAT(ip_allocated);
2616 log(4, ip_address_pool[best].address, s, session[s].tunnel,
2617 "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
2618
2619 return 1;
2620 }
2621
2622 void free_ip_address(sessionidt s)
2623 {
2624 int i = session[s].ip_pool_index;
2625
2626 if (!session[s].ip)
2627 return; // what the?
2628
2629 if (i < 0) // Is this actually part of the ip pool?
2630 i = 0;
2631
2632 STAT(ip_freed);
2633 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2634 session[s].ip = 0;
2635 ip_address_pool[i].assigned = 0;
2636 ip_address_pool[i].session = 0;
2637 ip_address_pool[i].last = time_now;
2638
2639
2640 CSTAT(call_free_ip_address);
2641
2642 }
2643
2644 //
2645 // Fsck the address pool against the session table.
2646 // Normally only called when we become a master.
2647 //
2648 // This isn't perfect: We aren't keep tracking of which
2649 // users used to have an IP address.
2650 //
2651 void rebuild_address_pool(void)
2652 {
2653 int i;
2654
2655 //
2656 // Zero the IP pool allocation, and build
2657 // a map from IP address to pool index.
2658 for (i = 1; i < MAXIPPOOL; ++i)
2659 {
2660 ip_address_pool[i].assigned = 0;
2661 ip_address_pool[i].session = 0;
2662 if (!ip_address_pool[i].address)
2663 continue;
2664
2665 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2666 }
2667
2668 for (i = 0; i < MAXSESSION; ++i)
2669 {
2670 int ipid;
2671 if (!session[i].ip || !session[i].tunnel)
2672 continue;
2673 ipid = - lookup_ipmap(htonl(session[i].ip));
2674
2675 if (session[i].ip_pool_index < 0)
2676 {
2677 // Not allocated out of the pool.
2678 if (ipid < 1) // Not found in the pool either? good.
2679 continue;
2680
2681 log(0, 0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2682 i, inet_toa(session[i].ip), ipid);
2683
2684 // Fall through and process it as part of the pool.
2685 }
2686
2687
2688 if (ipid > MAXIPPOOL || ipid < 0)
2689 {
2690 log(0, 0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2691 ipid = -1;
2692 session[i].ip_pool_index = ipid;
2693 continue;
2694 }
2695
2696 ip_address_pool[ipid].assigned = 1;
2697 ip_address_pool[ipid].session = i;
2698 ip_address_pool[ipid].last = time_now;
2699 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2700 session[i].ip_pool_index = ipid;
2701 cache_ipmap(session[i].ip, i); // Fix the ip map.
2702 }
2703 }
2704
2705 //
2706 // Fix the address pool to match a changed session.
2707 // (usually when the master sends us an update).
2708 void fix_address_pool(int sid)
2709 {
2710 int ipid;
2711
2712 ipid = session[sid].ip_pool_index;
2713
2714 if (ipid > ip_pool_size)
2715 return; // Ignore it. rebuild_address_pool will fix it up.
2716
2717 if (ip_address_pool[ipid].address != session[sid].ip)
2718 return; // Just ignore it. rebuild_address_pool will take care of it.
2719
2720 ip_address_pool[ipid].assigned = 1;
2721 ip_address_pool[ipid].session = sid;
2722 ip_address_pool[ipid].last = time_now;
2723 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2724 }
2725
2726 //
2727 // Add a block of addresses to the IP pool to hand out.
2728 //
2729 void add_to_ip_pool(u32 addr, u32 mask)
2730 {
2731 int i;
2732 if (mask == 0)
2733 mask = 0xffffffff; // Host route only.
2734
2735 addr &= mask;
2736
2737 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2738 return ;
2739
2740 for (i = addr ;(i & mask) == addr; ++i)
2741 {
2742 if ((i & 0xff) == 0 || (i&0xff) == 255)
2743 continue; // Skip 0 and broadcast addresses.
2744
2745 ip_address_pool[ip_pool_size].address = i;
2746 ip_address_pool[ip_pool_size].assigned = 0;
2747 ++ip_pool_size;
2748 if (ip_pool_size >= MAXIPPOOL)
2749 {
2750 log(0,0,0,0, "Overflowed IP pool adding %s\n", inet_toa(htonl(addr)) );
2751 return;
2752 }
2753 }
2754 }
2755
2756 // Initialize the IP address pool
2757 void initippool()
2758 {
2759 FILE *f;
2760 char *p;
2761 char buf[4096];
2762 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2763
2764 if (!(f = fopen(IPPOOLFILE, "r")))
2765 {
2766 log(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2767 exit(1);
2768 }
2769
2770 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2771 {
2772 char *pool = buf;
2773 buf[4095] = 0; // Force it to be zero terminated/
2774
2775 if (*buf == '#' || *buf == '\n')
2776 continue; // Skip comments / blank lines
2777 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2778 if ((p = (char *)strchr(buf, ':')))
2779 {
2780 ipt src;
2781 *p = '\0';
2782 src = inet_addr(buf);
2783 if (src == INADDR_NONE)
2784 {
2785 log(0, 0, 0, 0, "Invalid address pool IP %s\n", buf);
2786 exit(1);
2787 }
2788 // This entry is for a specific IP only
2789 if (src != config->bind_address)
2790 continue;
2791 *p = ':';
2792 pool = p+1;
2793 }
2794 if ((p = (char *)strchr(pool, '/')))
2795 {
2796 // It's a range
2797 int numbits = 0;
2798 u32 start = 0, mask = 0;
2799
2800 log(2, 0, 0, 0, "Adding IP address range %s\n", buf);
2801 *p++ = 0;
2802 if (!*p || !(numbits = atoi(p)))
2803 {
2804 log(0, 0, 0, 0, "Invalid pool range %s\n", buf);
2805 continue;
2806 }
2807 start = ntohl(inet_addr(pool));
2808 mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
2809
2810 // Add a static route for this pool
2811 log(5, 0, 0, 0, "Adding route for address pool %s/%u\n", inet_toa(htonl(start)), 32 + mask);
2812 routeset(0, start, mask, 0, 1);
2813
2814 add_to_ip_pool(start, mask);
2815 }
2816 else
2817 {
2818 // It's a single ip address
2819 add_to_ip_pool(inet_addr(pool), 0);
2820 }
2821 }
2822 fclose(f);
2823 log(1, 0, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2824 }
2825
2826 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
2827 {
2828 struct sockaddr_in snoop_addr = {0};
2829 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2830 return;
2831
2832 snoop_addr.sin_family = AF_INET;
2833 snoop_addr.sin_addr.s_addr = destination;
2834 snoop_addr.sin_port = ntohs(port);
2835
2836 log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
2837 packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
2838 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
2839 log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
2840 STAT(packets_snooped);
2841 }
2842
2843 void dump_acct_info()
2844 {
2845 char filename[1024];
2846 char timestr[64];
2847 time_t t = time(NULL);
2848 int i;
2849 FILE *f = NULL;
2850
2851
2852 CSTAT(call_dump_acct_info);
2853
2854 strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
2855 snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
2856
2857 for (i = 0; i < MAXSESSION; i++)
2858 {
2859 if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
2860 continue;
2861 if (!f)
2862 {
2863 time_t now = time(NULL);
2864 if (!(f = fopen(filename, "w")))
2865 {
2866 log(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
2867 return ;
2868 }
2869 log(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
2870 fprintf(f, "# dslwatch.pl dump file V1.01\n"
2871 "# host: %s\n"
2872 "# time: %ld\n"
2873 "# uptime: %ld\n"
2874 "# format: username ip qos uptxoctets downrxoctets\n",
2875 hostname,
2876 now,
2877 now - basetime);
2878 }
2879
2880 log(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
2881 fprintf(f, "%s %s %d %u %u\n",
2882 session[i].user, // username
2883 inet_toa(htonl(session[i].ip)), // ip
2884 (session[i].throttle) ? 2 : 1, // qos
2885 (u32)session[i].cin, // uptxoctets
2886 (u32)session[i].cout); // downrxoctets
2887
2888 session[i].pin = session[i].cin = 0;
2889 session[i].pout = session[i].cout = 0;
2890 }
2891
2892 if (f)
2893 fclose(f);
2894 }
2895
2896 // Main program
2897 int main(int argc, char *argv[])
2898 {
2899 int o;
2900 int optdebug = 0;
2901
2902 _program_name = strdup(argv[0]);
2903
2904 time(&basetime); // start clock
2905
2906 // scan args
2907 while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
2908 {
2909 switch (o)
2910 {
2911 case 'd':
2912 // Double fork to detach from terminal
2913 if (fork()) exit(0);
2914 if (fork()) exit(0);
2915 break;
2916 case 'v':
2917 optdebug++;
2918 break;
2919 case 'h':
2920 snprintf(hostname, sizeof(hostname), "%s", optarg);
2921 break;
2922 case '?':
2923 default:
2924 printf("Args are:\n"
2925 "\t-d\tDetach from terminal\n"
2926 "\t-c <file>\tConfig file\n"
2927 "\t-h <hostname>\tForce hostname\n"
2928 "\t-a <address>\tUse specific address\n"
2929 "\t-v\t\tDebug\n");
2930
2931 return (0);
2932 break;
2933 }
2934 }
2935
2936 // Start the timer routine off
2937 time(&time_now);
2938 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
2939 signal(SIGALRM, sigalrm_handler);
2940 siginterrupt(SIGALRM, 0);
2941
2942 initiptables();
2943 initplugins();
2944 initdata();
2945
2946 config->debug = optdebug;
2947
2948 init_tbf();
2949 init_cli(hostname);
2950 read_config_file();
2951
2952 log(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
2953 log(0, 0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
2954 log(0, 0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
2955 {
2956 struct rlimit rlim;
2957 rlim.rlim_cur = RLIM_INFINITY;
2958 rlim.rlim_max = RLIM_INFINITY;
2959 // Remove the maximum core size
2960 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
2961 log(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
2962 // Make core dumps go to /tmp
2963 chdir("/tmp");
2964 }
2965
2966 if (config->scheduler_fifo)
2967 {
2968 int ret;
2969 struct sched_param params = {0};
2970 params.sched_priority = 1;
2971
2972 if (get_nprocs() < 2)
2973 {
2974 log(0, 0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
2975 config->scheduler_fifo = 0;
2976 }
2977 else
2978 {
2979 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
2980 {
2981 log(1, 0, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
2982 }
2983 else
2984 {
2985 log(0, 0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
2986 config->scheduler_fifo = 0;
2987 }
2988 }
2989 }
2990
2991 /* Set up the cluster communications port. */
2992 if (cluster_init(config->bind_address) < 0)
2993 exit(1);
2994
2995 #ifdef BGP
2996 signal(SIGPIPE, SIG_IGN);
2997 bgp_setup(config->as_number);
2998 bgp_add_route(config->bind_address, 0xffffffff);
2999 if (*config->bgp_peer[0])
3000 bgp_start(&bgp_peers[0], config->bgp_peer[0],
3001 config->bgp_peer_as[0], 0); /* 0 = routing disabled */
3002
3003 if (*config->bgp_peer[1])
3004 bgp_start(&bgp_peers[1], config->bgp_peer[1],
3005 config->bgp_peer_as[1], 0);
3006 #endif /* BGP */
3007
3008 inittun();
3009 log(1, 0, 0, 0, "Set up on interface %s\n", config->tundevice);
3010
3011 initudp();
3012 initrad();
3013 initippool();
3014
3015 read_state();
3016
3017 signal(SIGHUP, sighup_handler);
3018 signal(SIGTERM, sigterm_handler);
3019 signal(SIGINT, sigterm_handler);
3020 signal(SIGQUIT, sigquit_handler);
3021 signal(SIGCHLD, sigchild_handler);
3022
3023 // Prevent us from getting paged out
3024 if (config->lock_pages)
3025 {
3026 if (!mlockall(MCL_CURRENT))
3027 log(1, 0, 0, 0, "Locking pages into memory\n");
3028 else
3029 log(0, 0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3030 }
3031
3032 alarm(1);
3033
3034 // Drop privileges here
3035 if (config->target_uid > 0 && geteuid() == 0)
3036 setuid(config->target_uid);
3037
3038 mainloop();
3039
3040 #ifdef BGP
3041 /* try to shut BGP down cleanly; with luck the sockets will be
3042 writable since we're out of the select */
3043 {
3044 int i;
3045 for (i = 0; i < BGP_NUM_PEERS; i++)
3046 if (bgp_peers[i].state == Established)
3047 bgp_stop(&bgp_peers[i]);
3048 }
3049 #endif /* BGP */
3050
3051 /* remove plugins (so cleanup code gets run) */
3052 plugins_done();
3053
3054 // Remove the PID file if we wrote it
3055 if (config->wrote_pid && *config->pid_file == '/')
3056 unlink(config->pid_file);
3057
3058 /* kill CLI children */
3059 signal(SIGTERM, SIG_IGN);
3060 kill(0, SIGTERM);
3061 return 0;
3062 }
3063
3064 void sighup_handler(int junk)
3065 {
3066 if (log_stream && log_stream != stderr)
3067 {
3068 fclose(log_stream);
3069 log_stream = NULL;
3070 }
3071
3072 read_config_file();
3073 }
3074
3075 void sigalrm_handler(int junk)
3076 {
3077 // Log current traffic stats
3078
3079 snprintf(config->bandwidth, sizeof(config->bandwidth),
3080 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3081 (udp_rx / 1024.0 / 1024.0 * 8),
3082 (eth_tx / 1024.0 / 1024.0 * 8),
3083 (eth_rx / 1024.0 / 1024.0 * 8),
3084 (udp_tx / 1024.0 / 1024.0 * 8),
3085 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3086 udp_rx_pkt, eth_rx_pkt);
3087
3088 udp_tx = udp_rx = 0;
3089 udp_rx_pkt = eth_rx_pkt = 0;
3090 eth_tx = eth_rx = 0;
3091
3092 if (config->dump_speed)
3093 printf("%s\n", config->bandwidth);
3094
3095 // Update the internal time counter
3096 time(&time_now);
3097 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3098 alarm(1);
3099
3100 {
3101 // Run timer hooks
3102 struct param_timer p = { time_now };
3103 run_plugins(PLUGIN_TIMER, &p);
3104 }
3105
3106 }
3107
3108 void sigterm_handler(int junk)
3109 {
3110 log(1, 0, 0, 0, "Shutting down cleanly\n");
3111 if (config->save_state)
3112 dump_state();
3113
3114 main_quit++;
3115 }
3116
3117 void sigquit_handler(int junk)
3118 {
3119 int i;
3120
3121 log(1, 0, 0, 0, "Shutting down without saving sessions\n");
3122 for (i = 1; i < MAXSESSION; i++)
3123 {
3124 if (session[i].opened)
3125 sessionkill(i, "L2TPNS Closing");
3126 }
3127 for (i = 1; i < MAXTUNNEL; i++)
3128 {
3129 if (tunnel[i].ip || tunnel[i].state)
3130 tunnelshutdown(i, "L2TPNS Closing");
3131 }
3132
3133 main_quit++;
3134 }
3135
3136 void sigchild_handler(int signal)
3137 {
3138 while (waitpid(-1, NULL, WNOHANG) > 0)
3139 ;
3140 }
3141
3142 void read_state()
3143 {
3144 struct stat sb;
3145 int i;
3146 ippoolt itmp;
3147 FILE *f;
3148 char magic[sizeof(DUMP_MAGIC) - 1];
3149 u32 buf[2];
3150
3151 if (!config->save_state)
3152 {
3153 unlink(STATEFILE);
3154 return ;
3155 }
3156
3157 if (stat(STATEFILE, &sb) < 0)
3158 {
3159 unlink(STATEFILE);
3160 return ;
3161 }
3162
3163 if (sb.st_mtime < (time(NULL) - 60))
3164 {
3165 log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
3166 unlink(STATEFILE);
3167 return ;
3168 }
3169
3170 f = fopen(STATEFILE, "r");
3171 unlink(STATEFILE);
3172
3173 if (!f)
3174 {
3175 log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3176 exit(1);
3177 }
3178
3179 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3180 {
3181 log(0, 0, 0, 0, "Bad state file magic\n");
3182 exit(1);
3183 }
3184
3185 log(1, 0, 0, 0, "Reading state information\n");
3186 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3187 {
3188 log(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3189 exit(1);
3190 }
3191
3192 if (buf[0] > ip_pool_size)
3193 {
3194 log(0, 0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3195 exit(1);
3196 }
3197
3198 log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
3199 for (i = 0; i < buf[0]; i++)
3200 {
3201 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3202 {
3203 log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3204 exit(1);
3205 }
3206
3207 if (itmp.address != ip_address_pool[i].address)
3208 {
3209 log(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3210 exit(1);
3211 }
3212
3213 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3214 }
3215
3216 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3217 {
3218 log(0, 0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3219 exit(1);
3220 }
3221
3222 log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3223 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3224 {
3225 log(0, 0, 0, 0, "Error reading tunnel data from state file\n");
3226 exit(1);
3227 }
3228
3229 for (i = 0; i < MAXTUNNEL; i++)
3230 {
3231 tunnel[i].controlc = 0;
3232 tunnel[i].controls = NULL;
3233 tunnel[i].controle = NULL;
3234 if (*tunnel[i].hostname)
3235 log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3236 }
3237
3238 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3239 {
3240 log(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
3241 exit(1);
3242 }
3243
3244 log(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
3245 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3246 {
3247 log(0, 0, 0, 0, "Error reading session data from state file\n");
3248 exit(1);
3249 }
3250
3251 for (i = 0; i < MAXSESSION; i++)
3252 {
3253 session[i].tbf_in = 0;
3254 session[i].tbf_out = 0;
3255 if (session[i].opened)
3256 {
3257 log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
3258 if (session[i].ip)
3259 sessionsetup(session[i].tunnel, i);
3260 }
3261 }
3262
3263 fclose(f);
3264 log(0, 0, 0, 0, "Loaded saved state information\n");
3265 }
3266
3267 void dump_state()
3268 {
3269 FILE *f;
3270 u32 buf[2];
3271
3272 if (!config->save_state)
3273 return;
3274
3275 do
3276 {
3277 if (!(f = fopen(STATEFILE, "w")))
3278 break;
3279
3280 log(1, 0, 0, 0, "Dumping state information\n");
3281
3282 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
3283 break;
3284
3285 log(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3286 buf[0] = ip_pool_size;
3287 buf[1] = sizeof(ippoolt);
3288 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3289 break;
3290 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
3291 break;
3292
3293 log(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3294 buf[0] = MAXTUNNEL;
3295 buf[1] = sizeof(tunnelt);
3296 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3297 break;
3298 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3299 break;
3300
3301 log(2, 0, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3302 buf[0] = MAXSESSION;
3303 buf[1] = sizeof(sessiont);
3304 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3305 break;
3306 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3307 break;
3308
3309 if (fclose(f) == 0)
3310 return ; // OK
3311 }
3312 while (0);
3313
3314 log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3315 unlink(STATEFILE);
3316 }
3317
3318 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
3319 {
3320 MD5_CTX ctx;
3321 *challenge_response = NULL;
3322
3323 if (!*config->l2tpsecret)
3324 {
3325 log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3326 return;
3327 }
3328
3329 log(4, 0, 0, 0, " Building challenge response for CHAP request\n");
3330
3331 *challenge_response = (char *)calloc(17, 1);
3332
3333 MD5Init(&ctx);
3334 MD5Update(&ctx, &id, 1);
3335 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3336 MD5Update(&ctx, challenge, challenge_length);
3337 MD5Final(*challenge_response, &ctx);
3338
3339 return;
3340 }
3341
3342 static int facility_value(char *name)
3343 {
3344 int i;
3345 for (i = 0; facilitynames[i].c_name; i++)
3346 {
3347 if (strcmp(facilitynames[i].c_name, name) == 0)
3348 return facilitynames[i].c_val;
3349 }
3350 return 0;
3351 }
3352
3353 void update_config()
3354 {
3355 int i;
3356 static int timeout = 0;
3357 static int interval = 0;
3358
3359 // Update logging
3360 closelog();
3361 syslog_log = 0;
3362 if (log_stream)
3363 {
3364 fclose(log_stream);
3365 log_stream = NULL;
3366 }
3367 if (*config->log_filename)
3368 {
3369 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3370 {
3371 char *p = config->log_filename + 7;
3372 if (*p)
3373 {
3374 openlog("l2tpns", LOG_PID, facility_value(p));
3375 syslog_log = 1;
3376 }
3377 }
3378 else if (strchr(config->log_filename, '/') == config->log_filename)
3379 {
3380 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3381 {
3382 fseek(log_stream, 0, SEEK_END);
3383 setbuf(log_stream, NULL);
3384 }
3385 else
3386 {
3387 log_stream = stderr;
3388 setbuf(log_stream, NULL);
3389 }
3390 }
3391 }
3392 else
3393 {
3394 log_stream = stderr;
3395 setbuf(log_stream, NULL);
3396 }
3397
3398
3399 // Update radius
3400 config->numradiusservers = 0;
3401 for (i = 0; i < MAXRADSERVER; i++)
3402 if (config->radiusserver[i])
3403 {
3404 config->numradiusservers++;
3405 // Set radius port: if not set, take the port from the
3406 // first radius server. For the first radius server,
3407 // take the #defined default value from l2tpns.h
3408
3409 // test twice, In case someone works with
3410 // a secondary radius server without defining
3411 // a primary one, this will work even then.
3412 if (i>0 && !config->radiusport[i])
3413 config->radiusport[i] = config->radiusport[i-1];
3414 if (!config->radiusport[i])
3415 config->radiusport[i] = RADPORT;
3416 }
3417
3418 if (!config->numradiusservers)
3419 {
3420 log(0, 0, 0, 0, "No RADIUS servers defined!\n");
3421 }
3422
3423 config->num_radfds = 2 << RADIUS_SHIFT;
3424
3425 // Update plugins
3426 for (i = 0; i < MAXPLUGINS; i++)
3427 {
3428 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3429 continue;
3430 if (*config->plugins[i])
3431 {
3432 // Plugin added
3433 add_plugin(config->plugins[i]);
3434 }
3435 else if (*config->old_plugins[i])
3436 {
3437 // Plugin removed
3438 remove_plugin(config->old_plugins[i]);
3439 }
3440 }
3441 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3442 if (!config->cleanup_interval) config->cleanup_interval = 10;
3443 if (!config->multi_read_count) config->multi_read_count = 10;
3444 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3445 if (!*config->cluster_interface)
3446 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3447
3448 if (!config->cluster_hb_interval)
3449 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3450
3451 if (!config->cluster_hb_timeout)
3452 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3453
3454 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3455 {
3456 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3457 // late, ensure we're sufficiently larger than that
3458 int t = 4 * config->cluster_hb_interval + 11;
3459
3460 if (config->cluster_hb_timeout < t)
3461 {
3462 log(0,0,0,0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3463 config->cluster_hb_timeout = t;
3464 }
3465
3466 // Push timing changes to the slaves immediately if we're the master
3467 if (config->cluster_iam_master)
3468 cluster_heartbeat();
3469
3470 interval = config->cluster_hb_interval;
3471 timeout = config->cluster_hb_timeout;
3472 }
3473
3474 // Write PID file
3475 if (*config->pid_file == '/' && !config->wrote_pid)
3476 {
3477 FILE *f;
3478 if ((f = fopen(config->pid_file, "w")))
3479 {
3480 fprintf(f, "%d\n", getpid());
3481 fclose(f);
3482 config->wrote_pid = 1;
3483 }
3484 else
3485 {
3486 log(0, 0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3487 }
3488 }
3489
3490 config->reload_config = 0;
3491 }
3492
3493 void read_config_file()
3494 {
3495 FILE *f;
3496
3497 if (!config->config_file) return;
3498 if (!(f = fopen(config->config_file, "r")))
3499 {
3500 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3501 return;
3502 }
3503
3504 log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
3505 cli_do_file(f);
3506 log(3, 0, 0, 0, "Done reading config file\n");
3507 fclose(f);
3508 update_config();
3509 }
3510
3511 int sessionsetup(tunnelidt t, sessionidt s)
3512 {
3513 // A session now exists, set it up
3514 ipt ip;
3515 char *user;
3516 sessionidt i;
3517 int r;
3518
3519 CSTAT(call_sessionsetup);
3520
3521
3522 log(3, session[s].ip, s, t, "Doing session setup for session\n");
3523
3524 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3525 {
3526 assign_ip_address(s);
3527 if (session[s].ip)
3528 log(3, 0, s, t, " No IP allocated. Assigned %s from pool\n",
3529 inet_toa(htonl(session[s].ip)));
3530 else
3531 log(0, 0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3532 }
3533
3534
3535 // Make sure this is right
3536 session[s].tunnel = t;
3537
3538 // zap old sessions with same IP and/or username
3539 // Don't kill gardened sessions - doing so leads to a DoS
3540 // from someone who doesn't need to know the password
3541 {
3542 ip = session[s].ip;
3543 user = session[s].user;
3544 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3545 {
3546 if (i == s) continue;
3547 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3548 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3549 sessionkill(i, "Duplicate session for users");
3550 }
3551 }
3552
3553 // Add the route for this session.
3554 //
3555 // Static IPs need to be routed. Anything else
3556 // is part of the IP address pool and is already routed,
3557 // it just needs to be added to the IP cache.
3558 if (session[s].ip_pool_index == -1) // static ip
3559 routeset(s, session[s].ip, 0, 0, 1);
3560 else
3561 cache_ipmap(session[s].ip, s);
3562
3563 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3564 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1);
3565
3566 if (!session[s].sid)
3567 {
3568 // did this session just finish radius?
3569 log(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
3570 sendipcp(t, s);
3571 session[s].sid = ++last_sid;
3572 }
3573
3574 // Run the plugin's against this new session.
3575 {
3576 struct param_new_session data = { &tunnel[t], &session[s] };
3577 run_plugins(PLUGIN_NEW_SESSION, &data);
3578 }
3579
3580 // Force throttling on or off (Actually : refresh the current throttling status)
3581 // This has the advantage of cleaning up after another throttled user who may have left
3582 // firewall rules lying around
3583 throttle_session(s, session[s].throttle);
3584
3585 session[s].last_packet = time_now;
3586
3587 {
3588 char *sessionip, *tunnelip;
3589 sessionip = strdup(inet_toa(htonl(session[s].ip)));
3590 tunnelip = strdup(inet_toa(htonl(tunnel[t].ip)));
3591 log(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
3592 session[s].user, sessionip, tunnelip, tunnel[t].hostname);
3593 if (sessionip) free(sessionip);
3594 if (tunnelip) free(tunnelip);
3595 }
3596
3597 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3598
3599 return 1; // RADIUS OK and IP allocated, done...
3600 }
3601
3602 //
3603 // This session just got dropped on us by the master or something.
3604 // Make sure our tables up up to date...
3605 //
3606 int load_session(sessionidt s, sessiont *new)
3607 {
3608 int i;
3609
3610 // Sanity checks.
3611 if (new->ip_pool_index >= MAXIPPOOL ||
3612 new->tunnel >= MAXTUNNEL)
3613 {
3614 log(0,0,s,0, "Strange session update received!\n");
3615 // FIXME! What to do here?
3616 return 0;
3617 }
3618
3619 //
3620 // Ok. All sanity checks passed. Now we're committed to
3621 // loading the new session.
3622 //
3623
3624 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3625
3626
3627 if (new->ip != session[s].ip) // Changed ip. fix up hash tables.
3628 {
3629 if (session[s].ip) // If there's an old one, remove it.
3630 {
3631 // Remove any routes if the IP has changed
3632 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3633 {
3634 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3635 session[s].route[i].ip = 0;
3636 }
3637
3638 if (session[s].ip_pool_index == -1) // static IP
3639 routeset(s, session[s].ip, 0, 0, 0);
3640 else // It's part of the IP pool, remove it manually.
3641 uncache_ipmap(session[s].ip);
3642 }
3643
3644 if (new->ip)
3645 {
3646 // If there's a new one, add it.
3647 if (new->ip_pool_index == -1)
3648 routeset(s, new->ip, 0, 0, 1);
3649 else
3650 cache_ipmap(new->ip, s);
3651 }
3652 }
3653
3654 // Update routed networks
3655 for (i = 0; i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3656 {
3657 if (new->route[i].ip == session[s].route[i].ip &&
3658 new->route[i].mask == session[s].route[i].mask)
3659 continue;
3660
3661 if (session[s].route[i].ip) // Remove the old one if it exists.
3662 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3663
3664 if (new->route[i].ip) // Add the new one if it exists.
3665 routeset(s, new->route[i].ip, new->route[i].mask, new->ip, 1);
3666 }
3667
3668 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3669 // for walking the sessions to forward byte counts to the master.
3670 config->cluster_highest_sessionid = s;
3671
3672 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3673
3674 // Do fixups into address pool.
3675 if (new->ip_pool_index != -1)
3676 fix_address_pool(s);
3677
3678 return 1;
3679 }
3680
3681 #ifdef RINGBUFFER
3682 void ringbuffer_dump(FILE *stream)
3683 {
3684 int i = ringbuffer->head;
3685
3686 while (i != ringbuffer->tail)
3687 {
3688 if (*ringbuffer->buffer[i].message)
3689 fprintf(stream, "%d-%s", ringbuffer->buffer[i].level, ringbuffer->buffer[i].message);
3690 if (++i == ringbuffer->tail) break;
3691 if (i == RINGBUFFER_SIZE) i = 0;
3692 }
3693 }
3694 #endif
3695
3696 void initplugins()
3697 {
3698 int i;
3699
3700 loaded_plugins = ll_init();
3701 // Initialize the plugins to nothing
3702 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3703 plugins[i] = ll_init();
3704 }
3705
3706 static void *open_plugin(char *plugin_name, int load)
3707 {
3708 char path[256] = "";
3709
3710 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3711 log(2, 0, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3712 return dlopen(path, RTLD_NOW);
3713 }
3714
3715 void add_plugin(char *plugin_name)
3716 {
3717 static struct pluginfuncs funcs = {
3718 _log,
3719 _log_hex,
3720 inet_toa,
3721 sessionbyuser,
3722 sessiontbysessionidt,
3723 sessionidtbysessiont,
3724 sessionkill,
3725 radiusnew,
3726 radiussend,
3727 };
3728
3729 void *p = open_plugin(plugin_name, 1);
3730 int (*initfunc)(struct pluginfuncs *);
3731 int i;
3732
3733 if (!p)
3734 {
3735 log(1, 0, 0, 0, " Plugin load failed: %s\n", dlerror());
3736 return;
3737 }
3738
3739 if (ll_contains(loaded_plugins, p))
3740 {
3741 dlclose(p);
3742 return;
3743 }
3744
3745 {
3746 int *v = dlsym(p, "__plugin_api_version");
3747 if (!v || *v != PLUGIN_API_VERSION)
3748 {
3749 log(1, 0, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
3750 dlclose(p);
3751 return;
3752 }
3753 }
3754
3755 if ((initfunc = dlsym(p, "plugin_init")))
3756 {
3757 if (!initfunc(&funcs))
3758 {
3759 log(1, 0, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
3760 dlclose(p);
3761 return;
3762 }
3763 }
3764
3765 ll_push(loaded_plugins, p);
3766
3767 for (i = 0; i < max_plugin_functions; i++)
3768 {
3769 void *x;
3770 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3771 {
3772 log(3, 0, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
3773 ll_push(plugins[i], x);
3774 }
3775 }
3776
3777 log(2, 0, 0, 0, " Loaded plugin %s\n", plugin_name);
3778 }
3779
3780 static void run_plugin_done(void *plugin)
3781 {
3782 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
3783
3784 if (donefunc)
3785 donefunc();
3786 }
3787
3788 void remove_plugin(char *plugin_name)
3789 {
3790 void *p = open_plugin(plugin_name, 0);
3791 int i;
3792
3793 if (!p)
3794 return;
3795
3796 for (i = 0; i < max_plugin_functions; i++)
3797 {
3798 void *x;
3799 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3800 ll_delete(plugins[i], x);
3801 }
3802
3803 if (ll_contains(loaded_plugins, p))
3804 {
3805 ll_delete(loaded_plugins, p);
3806 run_plugin_done(p);
3807 }
3808
3809 dlclose(p);
3810 log(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
3811 }
3812
3813 int run_plugins(int plugin_type, void *data)
3814 {
3815 int (*func)(void *data);
3816 if (!plugins[plugin_type] || plugin_type > max_plugin_functions) return 1;
3817
3818 ll_reset(plugins[plugin_type]);
3819 while ((func = ll_next(plugins[plugin_type])))
3820 {
3821 int rc;
3822 rc = func(data);
3823 if (rc == PLUGIN_RET_STOP) return 1;
3824 if (rc == PLUGIN_RET_ERROR) return 0;
3825 }
3826 return 1;
3827 }
3828
3829 void plugins_done()
3830 {
3831 void *p;
3832
3833 ll_reset(loaded_plugins);
3834 while ((p = ll_next(loaded_plugins)))
3835 run_plugin_done(p);
3836 }
3837
3838 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
3839 {
3840 char *resp;
3841 int l;
3842 struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
3843
3844
3845 if (log_stream && config->debug >= 4)
3846 {
3847 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
3848 dump_packet(buf, log_stream);
3849 }
3850
3851 resp = calloc(1400, 1);
3852 l = new_packet(PKT_RESP_ERROR, resp);
3853 *(int *)(resp + 6) = *(int *)(buf + 6);
3854
3855 param.type = ntohs(*(short *)(buf + 2));
3856 param.id = ntohl(*(int *)(buf + 6));
3857 param.data_length = ntohs(*(short *)(buf + 4)) - 10;
3858 param.data = (param.data_length > 0) ? (char *)(buf + 10) : NULL;
3859 param.response = resp;
3860 param.response_length = l;
3861
3862 run_plugins(PLUGIN_CONTROL, &param);
3863
3864 if (param.send_response)
3865 {
3866 send_packet(controlfd, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), param.response, param.response_length);
3867 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent Control packet response\n");
3868 }
3869
3870 free(resp);
3871 }
3872
3873 /*
3874 * HACK
3875 * Go through all of the tunnels and do some cleanups
3876 */
3877 void tunnel_clean()
3878 {
3879 int i;
3880
3881 log(1, 0, 0, 0, "Cleaning tunnels array\n");
3882
3883 for (i = 1; i < MAXTUNNEL; i++)
3884 {
3885 if (!tunnel[i].ip
3886 || !*tunnel[i].hostname
3887 || (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
3888 {
3889 tunnelclear(i);
3890 }
3891 }
3892 }
3893
3894 void tunnelclear(tunnelidt t)
3895 {
3896 if (!t) return;
3897 memset(&tunnel[t], 0, sizeof(tunnel[t]));
3898 tunnel[t].state = TUNNELFREE;
3899 }
3900
3901 tunnelidt new_tunnel()
3902 {
3903 tunnelidt i;
3904 for (i = 1; i < MAXTUNNEL; i++)
3905 {
3906 if (tunnel[i].state == TUNNELFREE)
3907 {
3908 log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
3909 if (i > config->cluster_highest_tunnelid)
3910 config->cluster_highest_tunnelid = i;
3911 return i;
3912 }
3913 }
3914 log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
3915 return 0;
3916 }
3917
3918 //
3919 // We're becoming the master. Do any required setup..
3920 //
3921 // This is principally telling all the plugins that we're
3922 // now a master, and telling them about all the sessions
3923 // that are active too..
3924 //
3925 void become_master(void)
3926 {
3927 int s;
3928 run_plugins(PLUGIN_BECOME_MASTER, NULL);
3929
3930 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
3931 {
3932 if (!session[s].tunnel) // Not an in-use session.
3933 continue;
3934
3935 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
3936 }
3937 }
3938
3939
3940
3941 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
3942 {
3943 int s, i;
3944 int count = 0;
3945 int buckets[64];
3946
3947 if (CLI_HELP_REQUESTED)
3948 return CLI_HELP_NO_ARGS;
3949
3950 time(&time_now);
3951 for (i = 0; i < 64;++i) buckets[i] = 0;
3952
3953 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
3954 {
3955 int idle;
3956 if (!session[s].tunnel)
3957 continue;
3958
3959 idle = time_now - session[s].last_packet;
3960 idle /= 5 ; // In multiples of 5 seconds.
3961 if (idle < 0)
3962 idle = 0;
3963 if (idle > 63)
3964 idle = 63;
3965
3966 ++count;
3967 ++buckets[idle];
3968 }
3969
3970 for (i = 0; i < 63; ++i)
3971 {
3972 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
3973 }
3974 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
3975 cli_print(cli, "%d total sessions open.", count);
3976 return CLI_OK;
3977 }
3978
3979 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
3980 {
3981 int s, i;
3982 int count = 0;
3983 int buckets[64];
3984
3985 if (CLI_HELP_REQUESTED)
3986 return CLI_HELP_NO_ARGS;
3987
3988 time(&time_now);
3989 for (i = 0; i < 64;++i) buckets[i] = 0;
3990
3991 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
3992 {
3993 int open = 0, d;
3994 if (!session[s].tunnel)
3995 continue;
3996
3997 d = time_now - session[s].opened;
3998 if (d < 0)
3999 d = 0;
4000 while (d > 1 && open < 32)
4001 {
4002 ++open;
4003 d >>= 1; // half.
4004 }
4005 ++count;
4006 ++buckets[open];
4007 }
4008
4009 s = 1;
4010 for (i = 0; i < 30; ++i)
4011 {
4012 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4013 s <<= 1;
4014 }
4015 cli_print(cli, "%d total sessions open.", count);
4016 return CLI_OK;
4017 }