95f1df4de8754a2788b6b532649d5f9547115530
[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 1.21 2004/08/02 06:06:28 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 if (!d[i]) continue;
545 e = (char**) d[i];
546 for (j = 0; j < 256; ++j) {
547 if (!e[j]) continue;
548 f = (char**) e[j];
549 for (k = 0; k < 256; ++k) {
550 if (!f[k]) continue;
551 g = (char**)f[k];
552 for (l = 0; l < 256; ++l) {
553 if (!g[l]) continue;
554 cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
555 ++count;
556 }
557 }
558 }
559 }
560 cli_print(cli, "%d entries in cache", count);
561 return CLI_OK;
562 }
563
564
565 // Find session by username, 0 for not found
566 // walled garden users aren't authenticated, so the username is
567 // reasonably useless. Ignore them to avoid incorrect actions
568 //
569 // This is VERY inefficent. Don't call it often. :)
570 //
571 sessionidt sessionbyuser(char *username)
572 {
573 int s;
574 CSTAT(call_sessionbyuser);
575
576 for (s = 1; s < MAXSESSION ; ++s) {
577 if (session[s].walled_garden)
578 continue; // Skip walled garden users.
579
580 if (!strncmp(session[s].user, username, 128))
581 return s;
582
583 }
584 return 0; // Not found.
585 }
586
587 void send_garp(ipt ip)
588 {
589 int s;
590 struct ifreq ifr;
591 u8 mac[6];
592
593 s = socket(PF_INET, SOCK_DGRAM, 0);
594 if (s < 0)
595 {
596 log(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
597 return;
598 }
599 memset(&ifr, 0, sizeof(ifr));
600 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
601 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
602 {
603 log(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
604 close(s);
605 return;
606 }
607 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
608 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
609 {
610 log(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
611 close(s);
612 return;
613 }
614 close(s);
615 sendarp(ifr.ifr_ifindex, mac, ip);
616 }
617
618 // Find session by username, 0 for not found
619 sessiont *sessiontbysessionidt(sessionidt s)
620 {
621 if (!s || s > MAXSESSION) return NULL;
622 return &session[s];
623 }
624
625 sessionidt sessionidtbysessiont(sessiont *s)
626 {
627 sessionidt val = s-session;
628 if (s < session || val > MAXSESSION) return 0;
629 return val;
630 }
631
632 // actually send a control message for a specific tunnel
633 void tunnelsend(u8 * buf, u16 l, tunnelidt t)
634 {
635 struct sockaddr_in addr;
636
637 CSTAT(call_tunnelsend);
638
639 if (!t)
640 {
641 static int backtrace_count = 0;
642 log(0, 0, 0, t, "tunnelsend called with 0 as tunnel id\n");
643 STAT(tunnel_tx_errors);
644 log_backtrace(backtrace_count, 5)
645 return;
646 }
647
648 if (!tunnel[t].ip)
649 {
650 static int backtrace_count = 0;
651 log(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
652 log_backtrace(backtrace_count, 5)
653 STAT(tunnel_tx_errors);
654 return;
655 }
656 memset(&addr, 0, sizeof(addr));
657 addr.sin_family = AF_INET;
658 *(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
659 addr.sin_port = htons(tunnel[t].port);
660
661 // sequence expected, if sequence in message
662 if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
663
664 // If this is a control message, deal with retries
665 if (*buf & 0x80)
666 {
667 tunnel[t].last = time_now; // control message sent
668 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
669 if (tunnel[t].try > 1)
670 {
671 STAT(tunnel_retries);
672 log(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
673 }
674 }
675
676 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
677 {
678 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",
679 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
680 STAT(tunnel_tx_errors);
681 return;
682 }
683
684 log_hex(5, "Send Tunnel Data", buf, l);
685 STAT(tunnel_tx_packets);
686 INC_STAT(tunnel_tx_bytes, l);
687 }
688
689 //
690 // Tiny helper function to write data to
691 // the 'tun' device.
692 //
693 int tun_write(u8 * data, int size)
694 {
695 return write(tunfd, data, size);
696 }
697
698 // process outgoing (to tunnel) IP
699 //
700 void processipout(u8 * buf, int len)
701 {
702 sessionidt s;
703 sessiont *sp;
704 tunnelidt t;
705 ipt ip;
706
707 char * data = buf; // Keep a copy of the originals.
708 int size = len;
709
710 u8 b[MAXETHER + 20];
711
712 CSTAT(call_processipout);
713
714 if (len < MIN_IP_SIZE)
715 {
716 log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
717 STAT(tunnel_tx_errors);
718 return;
719 }
720 if (len >= MAXETHER)
721 {
722 log(1, 0, 0, 0, "Oversize IP packet %d bytes\n", len);
723 STAT(tunnel_tx_errors);
724 return;
725 }
726
727 // Skip the tun header
728 buf += 4;
729 len -= 4;
730
731 // Got an IP header now
732 if (*(u8 *)(buf) >> 4 != 4)
733 {
734 log(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
735 return;
736 }
737
738 ip = *(u32 *)(buf + 16);
739 if (!(s = sessionbyip(ip)))
740 {
741 // Is this a packet for a session that doesn't exist?
742 static int rate = 0; // Number of ICMP packets we've sent this second.
743 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
744
745 if (last != time_now) {
746 last = time_now;
747 rate = 0;
748 }
749
750 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
751 {
752 log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
753 host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
754 }
755 return;
756 }
757 t = session[s].tunnel;
758 sp = &session[s];
759
760 if (sp->tbf_out)
761 {
762 // Are we throttling this session?
763 if (config->cluster_iam_master)
764 tbf_queue_packet(sp->tbf_out, data, size);
765 else
766 master_throttle_packet(sp->tbf_out, data, size);
767 return;
768 }
769 else if (sp->walled_garden && !config->cluster_iam_master)
770 {
771 // We are walled-gardening this
772 master_garden_packet(s, data, size);
773 return;
774 }
775
776 // Snooping this session, send it to intercept box
777 if (sp->snoop_ip && sp->snoop_port)
778 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
779
780 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
781
782 // Add on L2TP header
783 {
784 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
785 if (!p) {
786 log(3, session[s].ip, s, t, "failed to send packet in processipout.\n");
787 return;
788 }
789 tunnelsend(b, len + (p-b), t); // send it...
790 }
791
792 sp->cout += len; // byte count
793 sp->total_cout += len; // byte count
794 sp->pout++;
795 udp_tx += len;
796 sess_count[s].cout += len; // To send to master..
797 }
798
799 //
800 // Helper routine for the TBF filters.
801 // Used to send queued data in to the user!
802 //
803 void send_ipout(sessionidt s, u8 *buf, int len)
804 {
805 sessiont *sp;
806 tunnelidt t;
807 ipt ip;
808
809 u8 b[MAXETHER + 20];
810
811 if (len < 0 || len > MAXETHER) {
812 log(1,0,0,0, "Odd size IP packet: %d bytes\n", len);
813 return;
814 }
815
816 // Skip the tun header
817 buf += 4;
818 len -= 4;
819
820 ip = *(u32 *)(buf + 16);
821
822 if (!session[s].ip)
823 return;
824 t = session[s].tunnel;
825 sp = &session[s];
826
827 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
828
829 // Snooping this session.
830 if (sp->snoop_ip && sp->snoop_port)
831 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
832
833 // Add on L2TP header
834 {
835 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
836 if (!p) {
837 log(3, session[s].ip, s, t, "failed to send packet in send_ipout.\n");
838 return;
839 }
840 tunnelsend(b, len + (p-b), t); // send it...
841 }
842 sp->cout += len; // byte count
843 sp->total_cout += len; // byte count
844 sp->pout++;
845 udp_tx += len;
846 sess_count[s].cout += len; // To send to master..
847 }
848
849 // add an AVP (16 bit)
850 void control16(controlt * c, u16 avp, u16 val, u8 m)
851 {
852 u16 l = (m ? 0x8008 : 0x0008);
853 *(u16 *) (c->buf + c->length + 0) = htons(l);
854 *(u16 *) (c->buf + c->length + 2) = htons(0);
855 *(u16 *) (c->buf + c->length + 4) = htons(avp);
856 *(u16 *) (c->buf + c->length + 6) = htons(val);
857 c->length += 8;
858 }
859
860 // add an AVP (32 bit)
861 void control32(controlt * c, u16 avp, u32 val, u8 m)
862 {
863 u16 l = (m ? 0x800A : 0x000A);
864 *(u16 *) (c->buf + c->length + 0) = htons(l);
865 *(u16 *) (c->buf + c->length + 2) = htons(0);
866 *(u16 *) (c->buf + c->length + 4) = htons(avp);
867 *(u32 *) (c->buf + c->length + 6) = htonl(val);
868 c->length += 10;
869 }
870
871 // add an AVP (32 bit)
872 void controls(controlt * c, u16 avp, char *val, u8 m)
873 {
874 u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
875 *(u16 *) (c->buf + c->length + 0) = htons(l);
876 *(u16 *) (c->buf + c->length + 2) = htons(0);
877 *(u16 *) (c->buf + c->length + 4) = htons(avp);
878 memcpy(c->buf + c->length + 6, val, strlen(val));
879 c->length += 6 + strlen(val);
880 }
881
882 // add a binary AVP
883 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
884 {
885 u16 l = ((m ? 0x8000 : 0) + len + 6);
886 *(u16 *) (c->buf + c->length + 0) = htons(l);
887 *(u16 *) (c->buf + c->length + 2) = htons(0);
888 *(u16 *) (c->buf + c->length + 4) = htons(avp);
889 memcpy(c->buf + c->length + 6, val, len);
890 c->length += 6 + len;
891 }
892
893 // new control connection
894 controlt *controlnew(u16 mtype)
895 {
896 controlt *c;
897 if (!controlfree)
898 c = malloc(sizeof(controlt));
899 else
900 {
901 c = controlfree;
902 controlfree = c->next;
903 }
904 assert(c);
905 c->next = 0;
906 *(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
907 c->length = 12;
908 control16(c, 0, mtype, 1);
909 return c;
910 }
911
912 // send zero block if nothing is waiting
913 // (ZLB send).
914 void controlnull(tunnelidt t)
915 {
916 u8 buf[12];
917 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
918 return;
919
920 *(u16 *) (buf + 0) = htons(0xC802); // flags/ver
921 *(u16 *) (buf + 2) = htons(12); // length
922 *(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
923 *(u16 *) (buf + 6) = htons(0); // session
924 *(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
925 *(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
926 tunnelsend(buf, 12, t);
927 }
928
929 // add a control message to a tunnel, and send if within window
930 void controladd(controlt * c, tunnelidt t, sessionidt s)
931 {
932 *(u16 *) (c->buf + 2) = htons(c->length); // length
933 *(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
934 *(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
935 *(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
936 tunnel[t].ns++; // advance sequence
937 // link in message in to queue
938 if (tunnel[t].controlc)
939 tunnel[t].controle->next = c;
940 else
941 tunnel[t].controls = c;
942 tunnel[t].controle = c;
943 tunnel[t].controlc++;
944 // send now if space in window
945 if (tunnel[t].controlc <= tunnel[t].window)
946 {
947 tunnel[t].try = 0; // first send
948 tunnelsend(c->buf, c->length, t);
949 }
950 }
951
952 //
953 // Throttle or Unthrottle a session
954 //
955 // Throttle the data folling through a session
956 // to be no more than 'throttle' kbit/sec each way.
957 //
958 int throttle_session(sessionidt s, int throttle)
959 {
960 if (!session[s].tunnel)
961 return 0; // No-one home.
962
963 if (!*session[s].user)
964 return 0; // User not logged in
965
966 if (throttle) {
967 if (session[s].tbf_in || session[s].tbf_out) {
968 if (throttle == session[s].throttle)
969 return 1;
970
971 // Currently throttled but the rate is changing.
972
973 free_tbf(session[s].tbf_in);
974 free_tbf(session[s].tbf_out);
975 }
976
977 session[s].tbf_in = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipin);
978 session[s].tbf_out = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipout);
979
980 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
981 session[s].throttle = throttle;
982 cluster_send_session(s);
983 }
984
985 return 1;
986 }
987
988 // else Unthrottling.
989
990 if (!session[s].tbf_in && !session[s].tbf_out && !session[s].throttle)
991 return 0;
992
993 free_tbf(session[s].tbf_in);
994 session[s].tbf_in = 0;
995
996 free_tbf(session[s].tbf_out);
997 session[s].tbf_out = 0;
998
999 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
1000 session[s].throttle = throttle;
1001 cluster_send_session(s);
1002 }
1003
1004 return 0;
1005 }
1006
1007 // start tidy shutdown of session
1008 void sessionshutdown(sessionidt s, char *reason)
1009 {
1010 int dead = session[s].die;
1011 int walled_garden = session[s].walled_garden;
1012
1013
1014 CSTAT(call_sessionshutdown);
1015
1016 if (!session[s].tunnel)
1017 {
1018 log(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1019 return; // not a live session
1020 }
1021
1022 if (!dead)
1023 log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1024
1025 session[s].die = now() + 150; // Clean up in 15 seconds
1026
1027 {
1028 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1029 run_plugins(PLUGIN_KILL_SESSION, &data);
1030 }
1031
1032 // RADIUS Stop message
1033 if (session[s].opened && !walled_garden && !dead) {
1034 u16 r = session[s].radius;
1035 if (!r)
1036 {
1037 if (!(r = radiusnew(s)))
1038 {
1039 log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1040 STAT(radius_overflow);
1041 }
1042 else
1043 {
1044 int n;
1045 for (n = 0; n < 15; n++)
1046 radius[r].auth[n] = rand();
1047 }
1048 }
1049 if (r && radius[r].state != RADIUSSTOP)
1050 radiussend(r, RADIUSSTOP); // stop, if not already trying
1051 }
1052
1053 if (session[s].ip)
1054 { // IP allocated, clear and unroute
1055 int r;
1056 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1057 {
1058 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 0);
1059 session[s].route[r].ip = 0;
1060 }
1061
1062 if (session[s].ip_pool_index == -1) // static ip
1063 {
1064 routeset(s, session[s].ip, 0, 0, 0); // Delete route.
1065 session[s].ip = 0;
1066 }
1067 else
1068 free_ip_address(s);
1069
1070 if (session[s].throttle) // Unthrottle if throttled.
1071 throttle_session(s, 0);
1072 }
1073 { // Send CDN
1074 controlt *c = controlnew(14); // sending CDN
1075 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1076 control16(c, 14, s, 1); // assigned session (our end)
1077 controladd(c, session[s].tunnel, s); // send the message
1078 }
1079 cluster_send_session(s);
1080 }
1081
1082 void sendipcp(tunnelidt t, sessionidt s)
1083 {
1084 u8 buf[MAXCONTROL];
1085 u16 r = session[s].radius;
1086 u8 *q;
1087
1088 CSTAT(call_sendipcp);
1089
1090 if (!r)
1091 r = radiusnew(s);
1092
1093 if (radius[r].state != RADIUSIPCP)
1094 {
1095 radius[r].state = RADIUSIPCP;
1096 radius[r].try = 0;
1097 }
1098
1099 radius[r].retry = backoff(radius[r].try++);
1100 if (radius[r].try > 10)
1101 {
1102 radiusclear(r, s); // Clear radius session.
1103 sessionshutdown(s, "No reply on IPCP");
1104 return;
1105 }
1106
1107 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1108 if (!q) {
1109 log(3, session[s].ip, s, t, "failed to send packet in sendipcp.\n");
1110 return;
1111 }
1112
1113 *q = ConfigReq;
1114 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1115 *(u16 *) (q + 2) = htons(10);
1116 q[4] = 3;
1117 q[5] = 6;
1118 *(u32 *) (q + 6) = config->bind_address ? config->bind_address : my_address; // send my IP
1119 tunnelsend(buf, 10 + (q - buf), t); // send it
1120 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1121 }
1122
1123 // kill a session now
1124 void sessionkill(sessionidt s, char *reason)
1125 {
1126
1127 CSTAT(call_sessionkill);
1128
1129 session[s].die = now();
1130 sessionshutdown(s, reason); // close radius/routes, etc.
1131 if (session[s].radius)
1132 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1133
1134 log(2, 0, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1135
1136 throttle_session(s, 0); // Force session to be un-throttle. Free'ing TBF structures.
1137
1138 memset(&session[s], 0, sizeof(session[s]));
1139 session[s].tunnel = T_FREE; // Mark it as free.
1140 session[s].next = sessionfree;
1141 sessionfree = s;
1142 cli_session_actions[s].action = 0;
1143 cluster_send_session(s);
1144 }
1145
1146 // kill a tunnel now
1147 void tunnelkill(tunnelidt t, char *reason)
1148 {
1149 sessionidt s;
1150 controlt *c;
1151
1152 CSTAT(call_tunnelkill);
1153
1154 tunnel[t].state = TUNNELDIE;
1155
1156 // free control messages
1157 while ((c = tunnel[t].controls))
1158 {
1159 controlt * n = c->next;
1160 tunnel[t].controls = n;
1161 tunnel[t].controlc--;
1162 c->next = controlfree;
1163 controlfree = c;
1164 }
1165 // kill sessions
1166 for (s = 1; s < MAXSESSION; s++)
1167 if (session[s].tunnel == t)
1168 sessionkill(s, reason);
1169
1170 // free tunnel
1171 tunnelclear(t);
1172 log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
1173 cli_tunnel_actions[s].action = 0;
1174 cluster_send_tunnel(t);
1175 }
1176
1177 // shut down a tunnel cleanly
1178 void tunnelshutdown(tunnelidt t, char *reason)
1179 {
1180 sessionidt s;
1181
1182 CSTAT(call_tunnelshutdown);
1183
1184 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1185 {
1186 // never set up, can immediately kill
1187 tunnelkill(t, reason);
1188 return;
1189 }
1190 log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1191
1192 // close session
1193 for (s = 1; s < MAXSESSION; s++)
1194 if (session[s].tunnel == t)
1195 sessionkill(s, reason);
1196
1197 tunnel[t].state = TUNNELDIE;
1198 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1199 cluster_send_tunnel(t);
1200 // TBA - should we wait for sessions to stop?
1201 { // Send StopCCN
1202 controlt *c = controlnew(4); // sending StopCCN
1203 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message
1204 control16(c, 9, t, 1); // assigned tunnel (our end)
1205 controladd(c, t, 0); // send the message
1206 }
1207 }
1208
1209 // read and process packet on tunnel (UDP)
1210 void processudp(u8 * buf, int len, struct sockaddr_in *addr)
1211 {
1212 char *chapresponse = NULL;
1213 u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
1214 u8 *p = buf + 2;
1215
1216
1217 CSTAT(call_processudp);
1218
1219 udp_rx += len;
1220 udp_rx_pkt++;
1221 log_hex(5, "UDP Data", buf, len);
1222 STAT(tunnel_rx_packets);
1223 INC_STAT(tunnel_rx_bytes, len);
1224 if (len < 6)
1225 {
1226 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
1227 STAT(tunnel_rx_errors);
1228 return;
1229 }
1230 if ((buf[1] & 0x0F) != 2)
1231 {
1232 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1233 STAT(tunnel_rx_errors);
1234 return;
1235 }
1236 if (*buf & 0x40)
1237 { // length
1238 l = ntohs(*(u16 *) p);
1239 p += 2;
1240 }
1241 t = ntohs(*(u16 *) p);
1242 p += 2;
1243 s = ntohs(*(u16 *) p);
1244 p += 2;
1245 if (s >= MAXSESSION)
1246 {
1247 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
1248 STAT(tunnel_rx_errors);
1249 return;
1250 }
1251 if (t >= MAXTUNNEL)
1252 {
1253 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
1254 STAT(tunnel_rx_errors);
1255 return;
1256 }
1257 if (*buf & 0x08)
1258 { // ns/nr
1259 ns = ntohs(*(u16 *) p);
1260 p += 2;
1261 nr = ntohs(*(u16 *) p);
1262 p += 2;
1263 }
1264 if (*buf & 0x02)
1265 { // offset
1266 u16 o = ntohs(*(u16 *) p);
1267 p += o + 2;
1268 }
1269 if ((p - buf) > l)
1270 {
1271 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
1272 STAT(tunnel_rx_errors);
1273 return;
1274 }
1275 l -= (p - buf);
1276 if (*buf & 0x80)
1277 { // control
1278 u16 message = 0xFFFF; // message type
1279 u8 fatal = 0;
1280 u8 mandatorymessage = 0;
1281 u8 chap = 0; // if CHAP being used
1282 u16 asession = 0; // assigned session
1283 u32 amagic = 0; // magic number
1284 u8 aflags = 0; // flags from last LCF
1285 u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1286 int requestchap = 0; // do we request PAP instead of original CHAP request?
1287 char called[MAXTEL] = ""; // called number
1288 char calling[MAXTEL] = ""; // calling number
1289
1290 if (!config->cluster_iam_master) {
1291 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1292 return;
1293 }
1294
1295 if ((*buf & 0xCA) != 0xC8)
1296 {
1297 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
1298 STAT(tunnel_rx_errors);
1299 return;
1300 }
1301 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",
1302 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1303 // if no tunnel specified, assign one
1304 if (!t)
1305 {
1306 int i;
1307
1308 //
1309 // Is this a duplicate of the first packet? (SCCRQ)
1310 //
1311 for ( i = 1; i <= config->cluster_highest_tunnelid ; ++i) {
1312 if (tunnel[i].state != TUNNELOPENING ||
1313 tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
1314 tunnel[i].port != ntohs(addr->sin_port) )
1315 continue;
1316 t = i;
1317 break;
1318 }
1319 }
1320
1321 if (!t) {
1322 if (!(t = new_tunnel()))
1323 {
1324 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
1325 STAT(tunnel_overflow);
1326 return;
1327 }
1328 tunnelclear(t);
1329 tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
1330 tunnel[t].port = ntohs(addr->sin_port);
1331 tunnel[t].window = 4; // default window
1332 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);
1333 STAT(tunnel_created);
1334 }
1335
1336 // This is used to time out old tunnels
1337 tunnel[t].lastrec = time_now;
1338
1339 // check sequence of this message
1340 {
1341 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1342 // some to clear maybe?
1343 while (tunnel[t].controlc && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1344 {
1345 controlt *c = tunnel[t].controls;
1346 tunnel[t].controls = c->next;
1347 tunnel[t].controlc--;
1348 c->next = controlfree;
1349 controlfree = c;
1350 skip--;
1351 tunnel[t].try = 0; // we have progress
1352 }
1353
1354 // If the 'ns' just received is not the 'nr' we're
1355 // expecting, just send an ack and drop it.
1356 //
1357 // if 'ns' is less, then we got a retransmitted packet.
1358 // if 'ns' is greater than missed a packet. Either way
1359 // we should ignore it.
1360 if (ns != tunnel[t].nr)
1361 {
1362 // is this the sequence we were expecting?
1363 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);
1364 STAT(tunnel_rx_errors);
1365
1366 if (l) // Is this not a ZLB?
1367 controlnull(t);
1368 return;
1369 }
1370 // receiver advance (do here so quoted correctly in any sends below)
1371 if (l) tunnel[t].nr = (ns + 1);
1372 if (skip < 0) skip = 0;
1373 if (skip < tunnel[t].controlc)
1374 {
1375 // some control packets can now be sent that were previous stuck out of window
1376 int tosend = tunnel[t].window - skip;
1377 controlt *c = tunnel[t].controls;
1378 while (c && skip)
1379 {
1380 c = c->next;
1381 skip--;
1382 }
1383 while (c && tosend)
1384 {
1385 tunnel[t].try = 0; // first send
1386 tunnelsend(c->buf, c->length, t);
1387 c = c->next;
1388 tosend--;
1389 }
1390 }
1391 if (!tunnel[t].controlc)
1392 tunnel[t].retry = 0; // caught up
1393 }
1394 if (l)
1395 { // if not a null message
1396 // process AVPs
1397 while (l && !(fatal & 0x80))
1398 {
1399 u16 n = (ntohs(*(u16 *) p) & 0x3FF);
1400 u8 *b = p;
1401 u8 flags = *p;
1402 u16 mtype;
1403 p += n; // next
1404 if (l < n)
1405 {
1406 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
1407 STAT(tunnel_rx_errors);
1408 fatal = flags;
1409 return;
1410 }
1411 l -= n;
1412 if (flags & 0x40)
1413 {
1414 // handle hidden AVPs
1415 if (!*config->l2tpsecret)
1416 {
1417 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
1418 fatal = flags;
1419 continue;
1420 }
1421 if (!session[s].random_vector_length)
1422 {
1423 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
1424 fatal = flags;
1425 continue;
1426 }
1427 log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
1428 }
1429 if (*b & 0x3C)
1430 {
1431 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
1432 fatal = flags;
1433 continue; // next
1434 }
1435 b += 2;
1436 if (*(u16 *) (b))
1437 {
1438 log(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
1439 fatal = flags;
1440 continue; // next
1441 }
1442 b += 2;
1443 mtype = ntohs(*(u16 *) (b));
1444 b += 2;
1445 n -= 6;
1446
1447 log(4, ntohl(addr->sin_addr.s_addr), s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1448 switch (mtype)
1449 {
1450 case 0: // message type
1451 message = ntohs(*(u16 *) b);
1452 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Message type = %d (%s)\n", *b,
1453 l2tp_message_types[message]);
1454 mandatorymessage = flags;
1455 break;
1456 case 1: // result code
1457 {
1458 u16 rescode = ntohs(*(u16 *)(b));
1459 const char* resdesc = "(unknown)";
1460 if (message == 4) { /* StopCCN */
1461 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1462 resdesc = stopccn_result_codes[rescode];
1463 } else if (message == 14) { /* CDN */
1464 if (rescode <= MAX_CDN_RESULT_CODE)
1465 resdesc = cdn_result_codes[rescode];
1466 }
1467
1468 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Result Code %d: %s\n",
1469 rescode, resdesc);
1470 if (n >= 4) {
1471 u16 errcode = ntohs(*(u16 *)(b + 2));
1472 const char* errdesc = "(unknown)";
1473 if (errcode <= MAX_ERROR_CODE)
1474 errdesc = error_codes[errcode];
1475 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error Code %d: %s\n",
1476 errcode, errdesc);
1477 }
1478 if (n > 4)
1479 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error String: %.*s\n",
1480 n-4, b+4);
1481
1482 break;
1483 }
1484 break;
1485 case 2: // protocol version
1486 {
1487 version = ntohs(*(u16 *) (b));
1488 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Protocol version = %d\n", version);
1489 if (version && version != 0x0100)
1490 { // allow 0.0 and 1.0
1491 log(1, ntohl(addr->sin_addr.s_addr), s, t, " Bad protocol version %04X\n",
1492 version);
1493 fatal = flags;
1494 continue; // next
1495 }
1496 }
1497 break;
1498 case 3: // framing capabilities
1499 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
1500 break;
1501 case 4: // bearer capabilities
1502 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
1503 break;
1504 case 5: // tie breaker
1505 // We never open tunnels, so we don't care about tie breakers
1506 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
1507 continue;
1508 case 6: // firmware revision
1509 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
1510 break;
1511 case 7: // host name
1512 memset(tunnel[t].hostname, 0, 128);
1513 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1514 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1515 // TBA - to send to RADIUS
1516 break;
1517 case 8: // vendor name
1518 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1519 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1520 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1521 break;
1522 case 9: // assigned tunnel
1523 tunnel[t].far = ntohs(*(u16 *) (b));
1524 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1525 break;
1526 case 10: // rx window
1527 tunnel[t].window = ntohs(*(u16 *) (b));
1528 if (!tunnel[t].window)
1529 tunnel[t].window = 1; // window of 0 is silly
1530 log(4, ntohl(addr->sin_addr.s_addr), s, t, " rx window = %d\n", tunnel[t].window);
1531 break;
1532 case 11: // Challenge
1533 {
1534 log(4, ntohl(addr->sin_addr.s_addr), s, t, " LAC requested CHAP authentication for tunnel\n");
1535 build_chap_response(b, 2, n, &chapresponse);
1536 }
1537 break;
1538 case 14: // assigned session
1539 asession = session[s].far = ntohs(*(u16 *) (b));
1540 log(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
1541 break;
1542 case 15: // call serial number
1543 log(4, ntohl(addr->sin_addr.s_addr), s, t, " call serial number = %d\n", ntohl(*(u32 *)b));
1544 break;
1545 case 18: // bearer type
1546 log(4, ntohl(addr->sin_addr.s_addr), s, t, " bearer type = %d\n", ntohl(*(u32 *)b));
1547 // TBA - for RADIUS
1548 break;
1549 case 19: // framing type
1550 log(4, ntohl(addr->sin_addr.s_addr), s, t, " framing type = %d\n", ntohl(*(u32 *)b));
1551 // TBA
1552 break;
1553 case 21: // called number
1554 memset(called, 0, MAXTEL);
1555 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1556 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Called <%s>\n", called);
1557 break;
1558 case 22: // calling number
1559 memset(calling, 0, MAXTEL);
1560 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1561 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Calling <%s>\n", calling);
1562 break;
1563 case 23: // subtype
1564 break;
1565 case 24: // tx connect speed
1566 if (n == 4)
1567 {
1568 session[s].tx_connect_speed = ntohl(*(u32 *)b);
1569 }
1570 else
1571 {
1572 // AS5300s send connect speed as a string
1573 char tmp[30] = {0};
1574 memcpy(tmp, b, (n >= 30) ? 30 : n);
1575 session[s].tx_connect_speed = atol(tmp);
1576 }
1577 log(4, ntohl(addr->sin_addr.s_addr), s, t, " TX connect speed <%u>\n",
1578 session[s].tx_connect_speed);
1579 break;
1580 case 38: // rx connect speed
1581 if (n == 4)
1582 {
1583 session[s].rx_connect_speed = ntohl(*(u32 *)b);
1584 }
1585 else
1586 {
1587 // AS5300s send connect speed as a string
1588 char tmp[30] = {0};
1589 memcpy(tmp, b, (n >= 30) ? 30 : n);
1590 session[s].rx_connect_speed = atol(tmp);
1591 }
1592 log(4, ntohl(addr->sin_addr.s_addr), s, t, " RX connect speed <%u>\n",
1593 session[s].rx_connect_speed);
1594 break;
1595 case 25: // Physical Channel ID
1596 {
1597 u32 tmp = ntohl(*(u32 *)b);
1598 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Physical Channel ID <%X>\n", tmp);
1599 break;
1600 }
1601 case 29: // Proxy Authentication Type
1602 {
1603 u16 authtype = ntohs(*(u16 *)b);
1604 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Type %d (%s)\n",
1605 authtype, authtypes[authtype]);
1606 requestchap = (authtype == 2);
1607 break;
1608 }
1609 case 30: // Proxy Authentication Name
1610 {
1611 char authname[64] = {0};
1612 memcpy(authname, b, (n > 63) ? 63 : n);
1613 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Name (%s)\n",
1614 authname);
1615 break;
1616 }
1617 case 31: // Proxy Authentication Challenge
1618 {
1619 memcpy(radius[session[s].radius].auth, b, 16);
1620 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Challenge\n");
1621 break;
1622 }
1623 case 32: // Proxy Authentication ID
1624 {
1625 u16 authid = ntohs(*(u16 *)(b));
1626 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth ID (%d)\n",
1627 authid);
1628 if (session[s].radius)
1629 radius[session[s].radius].id = authid;
1630 break;
1631 }
1632 case 33: // Proxy Authentication Response
1633 {
1634 char authresp[64] = {0};
1635 memcpy(authresp, b, (n > 63) ? 63 : n);
1636 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Response\n");
1637 break;
1638 }
1639 case 27: // last send lcp
1640 { // find magic number
1641 u8 *p = b, *e = p + n;
1642 while (p < e && p[1])
1643 {
1644 if (*p == 5 && p[1] == 6)
1645 amagic = ntohl(*(u32 *) (p + 2));
1646 else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5)
1647 chap = 1;
1648 else if (*p == 7)
1649 aflags |= SESSIONPFC;
1650 else if (*p == 8)
1651 aflags |= SESSIONACFC;
1652 p += p[1];
1653 }
1654
1655 {
1656 char tmp[500] = {0};
1657 tmp[0] = ConfigReq;
1658 memcpy((tmp + 1), b, n);
1659 }
1660 }
1661 break;
1662 case 28: // last recv lcp confreq
1663 {
1664 char tmp[500] = {0};
1665 tmp[0] = ConfigReq;
1666 memcpy((tmp + 1), b, n);
1667 break;
1668 }
1669 case 26: // Initial Received LCP CONFREQ
1670 {
1671 char tmp[500] = {0};
1672 tmp[0] = ConfigReq;
1673 memcpy((tmp + 1), b, n);
1674 }
1675 break;
1676 case 39: // seq required - we control it as an LNS anyway...
1677 break;
1678 case 36: // Random Vector
1679 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Random Vector received. Enabled AVP Hiding.\n");
1680 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1681 memcpy(session[s].random_vector, b, n);
1682 session[s].random_vector_length = n;
1683 break;
1684 default:
1685 log(2, ntohl(addr->sin_addr.s_addr), s, t, " Unknown AVP type %d\n", mtype);
1686 fatal = flags;
1687 continue; // next
1688 }
1689 }
1690 // process message
1691 if (fatal & 0x80)
1692 tunnelshutdown(t, "Unknown Mandatory AVP");
1693 else
1694 switch (message)
1695 {
1696 case 1: // SCCRQ - Start Control Connection Request
1697 {
1698 controlt *c = controlnew(2); // sending SCCRP
1699 control16(c, 2, version, 1); // protocol version
1700 control32(c, 3, 3, 1); // framing
1701 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1702 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1703 control16(c, 9, t, 1); // assigned tunnel
1704 controladd(c, t, s); // send the resply
1705 }
1706 tunnel[t].state = TUNNELOPENING;
1707 break;
1708 case 2: // SCCRP
1709 tunnel[t].state = TUNNELOPEN;
1710 break;
1711 case 3: // SCCN
1712 tunnel[t].state = TUNNELOPEN;
1713 controlnull(t); // ack
1714 break;
1715 case 4: // StopCCN
1716 controlnull(t); // ack
1717 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1718 tunnelkill(t, "Stopped"); // Immediately force everything dead
1719 break;
1720 case 6: // HELLO
1721 controlnull(t); // simply ACK
1722 break;
1723 case 7: // OCRQ
1724 // TBA
1725 break;
1726 case 8: // OCRO
1727 // TBA
1728 break;
1729 case 9: // OCCN
1730 // TBA
1731 break;
1732 case 10: // ICRQ
1733 if (!sessionfree)
1734 {
1735 STAT(session_overflow);
1736 tunnelshutdown(t, "No free sessions");
1737 }
1738 else
1739 {
1740 u16 r;
1741 controlt *c;
1742
1743 s = sessionfree;
1744 sessionfree = session[s].next;
1745 memset(&session[s], 0, sizeof(session[s]));
1746
1747 if (s > config->cluster_highest_sessionid)
1748 config->cluster_highest_sessionid = s;
1749
1750 // make a RADIUS session
1751 if (!(r = radiusnew(s)))
1752 {
1753 log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
1754 sessionkill(s, "no free RADIUS sesions");
1755 return;
1756 }
1757
1758 c = controlnew(11); // sending ICRP
1759 session[s].id = sessionid++;
1760 session[s].opened = time(NULL);
1761 session[s].tunnel = t;
1762 session[s].far = asession;
1763 session[s].last_packet = time_now;
1764 log(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1765 control16(c, 14, s, 1); // assigned session
1766 controladd(c, t, s); // send the reply
1767 {
1768 // Generate a random challenge
1769 int n;
1770 for (n = 0; n < 15; n++)
1771 radius[r].auth[n] = rand();
1772 }
1773 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1774 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1775 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1776 STAT(session_created);
1777 }
1778 break;
1779 case 11: // ICRP
1780 // TBA
1781 break;
1782 case 12: // ICCN
1783 session[s].magic = amagic; // set magic number
1784 session[s].l2tp_flags = aflags; // set flags received
1785 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
1786 controlnull(t); // ack
1787 // In CHAP state, request PAP instead
1788 if (requestchap)
1789 initlcp(t, s);
1790 break;
1791 case 14: // CDN
1792 controlnull(t); // ack
1793 sessionshutdown(s, "Closed (Received CDN)");
1794 break;
1795 case 0xFFFF:
1796 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
1797 break;
1798 default:
1799 STAT(tunnel_rx_errors);
1800 if (mandatorymessage & 0x80)
1801 tunnelshutdown(t, "Unknown message");
1802 else
1803 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
1804 break;
1805 }
1806 if (chapresponse) free(chapresponse);
1807 cluster_send_tunnel(t);
1808 }
1809 else
1810 {
1811 log(4, 0, s, t, " Got a ZLB ack\n");
1812 }
1813 }
1814 else
1815 { // data
1816 u16 prot;
1817
1818 log_hex(5, "Receive Tunnel Data", p, l);
1819 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1820 { // HDLC address header, discard
1821 p += 2;
1822 l -= 2;
1823 }
1824 if (l < 2)
1825 {
1826 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
1827 STAT(tunnel_rx_errors);
1828 return;
1829 }
1830 if (*p & 1)
1831 {
1832 prot = *p++;
1833 l--;
1834 }
1835 else
1836 {
1837 prot = ntohs(*(u16 *) p);
1838 p += 2;
1839 l -= 2;
1840 }
1841
1842 if (s && !session[s].tunnel) // Is something wrong??
1843 {
1844 if (!config->cluster_iam_master)
1845 {
1846 // Pass it off to the master to deal with..
1847 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1848 return;
1849 }
1850
1851
1852 log(1, ntohl(addr->sin_addr.s_addr), s, t, "UDP packet contains session %d "
1853 "but no session[%d].tunnel exists (LAC said"
1854 " tunnel = %d). Dropping packet.\n", s, s, t);
1855 STAT(tunnel_rx_errors);
1856 return;
1857 }
1858
1859 if (session[s].die)
1860 {
1861 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
1862 // I'm pretty sure this isn't right -- mo.
1863 // return; // closing session, PPP not processed
1864 }
1865 if (prot == PPPPAP)
1866 {
1867 session[s].last_packet = time_now;
1868 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1869 processpap(t, s, p, l);
1870 }
1871 else if (prot == PPPCHAP)
1872 {
1873 session[s].last_packet = time_now;
1874 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1875 processchap(t, s, p, l);
1876 }
1877 else if (prot == PPPLCP)
1878 {
1879 session[s].last_packet = time_now;
1880 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1881 processlcp(t, s, p, l);
1882 }
1883 else if (prot == PPPIPCP)
1884 {
1885 session[s].last_packet = time_now;
1886 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1887 processipcp(t, s, p, l);
1888 }
1889 else if (prot == PPPCCP)
1890 {
1891 session[s].last_packet = time_now;
1892 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1893 processccp(t, s, p, l);
1894 }
1895 else if (prot == PPPIP)
1896 {
1897 if (!config->cluster_iam_master)
1898 {
1899 // We're a slave. Should we forward this packet to the master?
1900
1901 // Is this a walled garden session, or something that needs it's
1902 // idle time updated??
1903
1904 // Maintain the idle timeouts on the master. If this would
1905 // significantly reset the idletimeout, run it via the master
1906 // to refresh the master's idle timer.
1907 // Not sure this is ideal: It may re-order packets.
1908
1909 if (session[s].walled_garden || (session[s].last_packet + (ECHO_TIMEOUT/2)) < time_now)
1910 {
1911 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1912 session[s].last_packet = time_now;
1913 return;
1914 }
1915 // fall through to processipin.
1916 } else
1917 session[s].last_packet = time_now;
1918 processipin(t, s, p, l);
1919 }
1920 else
1921 {
1922 STAT(tunnel_rx_errors);
1923 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
1924 }
1925 }
1926 }
1927
1928 // read and process packet on tun
1929 void processtun(u8 * buf, int len)
1930 {
1931 log_hex(5, "Receive TUN Data", buf, len);
1932 STAT(tun_rx_packets);
1933 INC_STAT(tun_rx_bytes, len);
1934
1935 CSTAT(call_processtun);
1936
1937 eth_rx_pkt++;
1938 eth_rx += len;
1939 if (len < 22)
1940 {
1941 log(1, 0, 0, 0, "Short tun packet %d bytes\n", len);
1942 STAT(tun_rx_errors);
1943 return;
1944 }
1945
1946 if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
1947 processipout(buf, len);
1948 // Else discard.
1949 }
1950
1951 //
1952 // Maximum number of actions to complete.
1953 // This is to avoid sending out too many packets
1954 // at once.
1955 #define MAX_ACTIONS 500
1956
1957 int regular_cleanups(void)
1958 {
1959 static sessionidt s = 0; // Next session to check for actions on.
1960 tunnelidt t;
1961 int count=0,i;
1962 u16 r;
1963 static clockt next_acct = 0;
1964 int a;
1965
1966 log(3, 0, 0, 0, "Begin regular cleanup\n");
1967
1968 for (r = 1; r < MAXRADIUS; r++)
1969 {
1970 if (!radius[r].state)
1971 continue;
1972 if (radius[r].retry)
1973 {
1974 if (radius[r].retry <= TIME)
1975 radiusretry(r);
1976 } else
1977 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
1978 }
1979 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
1980 {
1981 // check for expired tunnels
1982 if (tunnel[t].die && tunnel[t].die <= TIME)
1983 {
1984 STAT(tunnel_timeout);
1985 tunnelkill(t, "Expired");
1986 continue;
1987 }
1988 // check for message resend
1989 if (tunnel[t].retry && tunnel[t].controlc)
1990 {
1991 // resend pending messages as timeout on reply
1992 if (tunnel[t].retry <= TIME)
1993 {
1994 controlt *c = tunnel[t].controls;
1995 u8 w = tunnel[t].window;
1996 tunnel[t].try++; // another try
1997 if (tunnel[t].try > 5)
1998 tunnelkill(t, "Timeout on control message"); // game over
1999 else
2000 while (c && w--)
2001 {
2002 tunnelsend(c->buf, c->length, t);
2003 c = c->next;
2004 }
2005 }
2006 }
2007 // Send hello
2008 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2009 {
2010 controlt *c = controlnew(6); // sending HELLO
2011 controladd(c, t, 0); // send the message
2012 log(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
2013 }
2014
2015 // Check for tunnel changes requested from the CLI
2016 if ((a = cli_tunnel_actions[t].action))
2017 {
2018 cli_tunnel_actions[t].action = 0;
2019 if (a & CLI_TUN_KILL)
2020 {
2021 log(2, tunnel[t].ip, 0, t, "Dropping tunnel by CLI\n");
2022 tunnelshutdown(t, "Requested by administrator");
2023 }
2024 }
2025
2026 }
2027
2028 count = 0;
2029 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2030 {
2031 s++;
2032 if (s > config->cluster_highest_sessionid)
2033 s = 1;
2034
2035 if (!session[s].tunnel) // Session isn't in use
2036 continue;
2037
2038 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2039 {
2040 // IPCP has not completed yet. Resend
2041 log(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2042 sendipcp(session[s].tunnel, s);
2043 }
2044
2045 // check for expired sessions
2046 if (session[s].die && session[s].die <= TIME)
2047 {
2048 sessionkill(s, "Expired");
2049 if (++count >= MAX_ACTIONS) break;
2050 continue;
2051 }
2052
2053 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2054 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2055 {
2056 sessionkill(s, "No response to LCP ECHO requests");
2057 STAT(session_timeout);
2058 if (++count >= MAX_ACTIONS) break;
2059 continue;
2060 }
2061
2062 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2063 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2064 {
2065 u8 b[MAXCONTROL] = {0};
2066
2067 u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2068 if (!q) {
2069 log(3, session[s].ip, s, t, "failed to send ECHO packet.\n");
2070 continue;
2071 }
2072
2073 *q = EchoReq;
2074 *(u8 *)(q + 1) = (time_now % 255); // ID
2075 *(u16 *)(q + 2) = htons(8); // Length
2076 *(u32 *)(q + 4) = 0; // Magic Number (not supported)
2077
2078 log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2079 (int)(time_now - session[s].last_packet));
2080 tunnelsend(b, 24, session[s].tunnel); // send it
2081 if (++count >= MAX_ACTIONS) break;
2082 }
2083
2084 // Check for actions requested from the CLI
2085 if ((a = cli_session_actions[s].action))
2086 {
2087 int send = 0;
2088
2089 cli_session_actions[s].action = 0;
2090 if (a & CLI_SESS_KILL)
2091 {
2092 log(2, 0, s, session[s].tunnel, "Dropping session by CLI\n");
2093 sessionshutdown(s, "Requested by administrator");
2094 a = 0; // dead, no need to check for other actions
2095 }
2096
2097 if (a & CLI_SESS_SNOOP)
2098 {
2099 log(2, 0, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2100 inet_toa(cli_session_actions[s].snoop_ip), cli_session_actions[s].snoop_port);
2101
2102 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2103 session[s].snoop_port = cli_session_actions[s].snoop_port;
2104 send++;
2105 }
2106
2107 if (a & CLI_SESS_NOSNOOP)
2108 {
2109 log(2, 0, s, session[s].tunnel, "Unsnooping session by CLI\n");
2110 session[s].snoop_ip = 0;
2111 session[s].snoop_port = 0;
2112 send++;
2113 }
2114
2115 if (a & CLI_SESS_THROTTLE)
2116 {
2117 log(2, 0, s, session[s].tunnel, "Throttling session by CLI (to %d)\n",
2118 cli_session_actions[s].throttle);
2119
2120 throttle_session(s, cli_session_actions[s].throttle);
2121 }
2122
2123 if (a & CLI_SESS_NOTHROTTLE)
2124 {
2125 log(2, 0, s, session[s].tunnel, "Un-throttling session by CLI\n");
2126 throttle_session(s, 0);
2127 }
2128
2129 if (send)
2130 cluster_send_session(s);
2131
2132 if (++count >= MAX_ACTIONS) break;
2133 }
2134 }
2135
2136 if (config->accounting_dir && next_acct <= TIME)
2137 {
2138 // Dump accounting data
2139 next_acct = TIME + ACCT_TIME;
2140 dump_acct_info();
2141 }
2142
2143 if (count >= MAX_ACTIONS)
2144 return 1; // Didn't finish!
2145
2146 log(3, 0, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2147 return 0;
2148 }
2149
2150
2151 //
2152 // Are we in the middle of a tunnel update, or radius
2153 // requests??
2154 //
2155 int still_busy(void)
2156 {
2157 int i;
2158 static int last_talked = 0;
2159 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i) {
2160 if (!tunnel[i].controlc)
2161 continue;
2162
2163 if (last_talked != TIME) {
2164 log(2,0,0,0, "Tunnel %d still has un-acked control messages.\n", i);
2165 last_talked = TIME;
2166 }
2167 return 1;
2168 }
2169
2170 for (i = 1; i < MAXRADIUS; i++)
2171 {
2172 if (radius[i].state == RADIUSNULL)
2173 continue;
2174 if (radius[i].state == RADIUSWAIT)
2175 continue;
2176
2177 if (last_talked != TIME) {
2178 log(2,0,0,0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2179 last_talked = TIME;
2180 }
2181 return 1;
2182 }
2183
2184 return 0;
2185 }
2186
2187 // main loop - gets packets on tun or udp and processes them
2188 void mainloop(void)
2189 {
2190 fd_set cr;
2191 int cn, i;
2192 u8 buf[65536];
2193 struct timeval to;
2194 clockt next_cluster_ping = 0; // send initial ping immediately
2195 time_t next_clean = time_now + config->cleanup_interval;
2196
2197 log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2198 udpfd, tunfd, cluster_sockfd, controlfd);
2199
2200 FD_ZERO(&cr);
2201 FD_SET(udpfd, &cr);
2202 FD_SET(tunfd, &cr);
2203 FD_SET(controlfd, &cr);
2204 FD_SET(clifd, &cr);
2205 if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
2206 cn = udpfd;
2207 if (cn < tunfd) cn = tunfd;
2208 if (cn < controlfd) cn = controlfd;
2209 if (cn < clifd) cn = clifd;
2210 if (cn < cluster_sockfd) cn = cluster_sockfd;
2211 for (i = 0; i < config->num_radfds; i++)
2212 {
2213 if (!radfds[i]) continue;
2214 FD_SET(radfds[i], &cr);
2215 if (radfds[i] > cn)
2216 cn = radfds[i];
2217 }
2218
2219 while (!main_quit || still_busy())
2220 {
2221 fd_set r;
2222 int n = cn;
2223 #ifdef BGP
2224 fd_set w;
2225 int bgp_set[BGP_NUM_PEERS];
2226 #endif /* BGP */
2227
2228 if (config->reload_config)
2229 {
2230 // Update the config state based on config settings
2231 update_config();
2232 }
2233
2234 memcpy(&r, &cr, sizeof(fd_set));
2235 to.tv_sec = 0;
2236 to.tv_usec = 100000; // 1/10th of a second.
2237
2238 #ifdef BGP
2239 FD_ZERO(&w);
2240 for (i = 0; i < BGP_NUM_PEERS; i++)
2241 {
2242 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2243 if (bgp_set[i] & 1)
2244 {
2245 FD_SET(bgp_peers[i].sock, &r);
2246 if (bgp_peers[i].sock > n)
2247 n = bgp_peers[i].sock;
2248 }
2249
2250 if (bgp_set[i] & 2)
2251 {
2252 FD_SET(bgp_peers[i].sock, &w);
2253 if (bgp_peers[i].sock > n)
2254 n = bgp_peers[i].sock;
2255 }
2256 }
2257
2258 n = select(n + 1, &r, &w, 0, &to);
2259 #else /* BGP */
2260 n = select(n + 1, &r, 0, 0, &to);
2261 #endif /* BGP */
2262
2263 TIME = now();
2264 if (n < 0)
2265 {
2266 if (errno == EINTR)
2267 continue;
2268
2269 log(0, 0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2270 main_quit++;
2271 break;
2272 }
2273 else if (n)
2274 {
2275 struct sockaddr_in addr;
2276 int alen = sizeof(addr);
2277 if (FD_ISSET(udpfd, &r))
2278 {
2279 int c, n;
2280 for (c = 0; c < config->multi_read_count; c++)
2281 {
2282 if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2283 processudp(buf, n, &addr);
2284 else
2285 break;
2286 }
2287 }
2288 if (FD_ISSET(tunfd, &r))
2289 {
2290 int c, n;
2291 for (c = 0; c < config->multi_read_count; c++)
2292 {
2293 if ((n = read(tunfd, buf, sizeof(buf))) > 0)
2294 processtun(buf, n);
2295 else
2296 break;
2297 }
2298 }
2299 for (i = 0; i < config->num_radfds; i++)
2300 if (FD_ISSET(radfds[i], &r))
2301 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2302 if (FD_ISSET(cluster_sockfd, &r)) {
2303 int size;
2304 size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
2305 processcluster(buf, size, addr.sin_addr.s_addr);
2306 }
2307 if (FD_ISSET(controlfd, &r))
2308 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
2309 if (FD_ISSET(clifd, &r))
2310 {
2311 struct sockaddr_in addr;
2312 int sockfd;
2313 int len = sizeof(addr);
2314
2315 if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
2316 {
2317 log(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
2318 continue;
2319 }
2320 else
2321 {
2322 cli_do(sockfd);
2323 close(sockfd);
2324 }
2325 }
2326 }
2327
2328 // Runs on every machine (master and slaves).
2329 if (cluster_sockfd && next_cluster_ping <= TIME)
2330 {
2331 // Check to see which of the cluster is still alive..
2332
2333 cluster_send_ping(basetime); // Only does anything if we're a slave
2334 cluster_check_master(); // ditto.
2335
2336 cluster_heartbeat(); // Only does anything if we're a master.
2337 cluster_check_slaves(); // ditto.
2338
2339 master_update_counts(); // If we're a slave, send our byte counters to our master.
2340
2341 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2342 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2343 else
2344 next_cluster_ping = TIME + config->cluster_hb_interval;
2345 }
2346
2347 // Run token bucket filtering queue..
2348 // Only run it every 1/10th of a second.
2349 // Runs on all machines both master and slave.
2350 {
2351 static clockt last_run = 0;
2352 if (last_run != TIME) {
2353 last_run = TIME;
2354 tbf_run_timer();
2355 }
2356 }
2357
2358 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2359 * something to read, else under load this will never actually run....
2360 *
2361 */
2362 if (config->cluster_iam_master && next_clean <= time_now) {
2363 if (regular_cleanups()) { // Did it finish?
2364 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2365 } else {
2366 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2367 }
2368 }
2369
2370 #ifdef BGP
2371 for (i = 0; i < BGP_NUM_PEERS; i++)
2372 {
2373 bgp_process(&bgp_peers[i],
2374 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
2375 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
2376 }
2377 #endif /* BGP */
2378 }
2379
2380 // Are we the master and shutting down??
2381 if (config->cluster_iam_master)
2382 cluster_heartbeat(); // Flush any queued changes..
2383
2384 // Ok. Notify everyone we're shutting down. If we're
2385 // the master, this will force an election.
2386 cluster_send_ping(0);
2387
2388 //
2389 // Important!!! We MUST not process any packets past this point!
2390 }
2391
2392 // Init data structures
2393 void initdata(void)
2394 {
2395 int i;
2396
2397 _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2398 if (_statistics == MAP_FAILED)
2399 {
2400 log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
2401 exit(1);
2402 }
2403 config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2404 if (config == MAP_FAILED)
2405 {
2406 log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
2407 exit(1);
2408 }
2409 memset(config, 0, sizeof(struct configt));
2410 time(&config->start_time);
2411 strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
2412 tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2413 if (tunnel == MAP_FAILED)
2414 {
2415 log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
2416 exit(1);
2417 }
2418 session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2419 if (session == MAP_FAILED)
2420 {
2421 log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
2422 exit(1);
2423 }
2424
2425 sess_count = mmap(NULL, sizeof(sessioncountt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2426 if (sess_count == MAP_FAILED)
2427 {
2428 log(0, 0, 0, 0, "Error doing mmap for sessions_count: %s\n", strerror(errno));
2429 exit(1);
2430 }
2431
2432 radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2433 if (radius == MAP_FAILED)
2434 {
2435 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2436 exit(1);
2437 }
2438 ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2439 if (ip_address_pool == MAP_FAILED)
2440 {
2441 log(0, 0, 0, 0, "Error doing mmap for ip_address_pool: %s\n", strerror(errno));
2442 exit(1);
2443 }
2444 #ifdef RINGBUFFER
2445 ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2446 if (ringbuffer == MAP_FAILED)
2447 {
2448 log(0, 0, 0, 0, "Error doing mmap for ringbuffer: %s\n", strerror(errno));
2449 exit(1);
2450 }
2451 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2452 #endif
2453
2454 cli_session_actions = mmap(NULL, sizeof(struct cli_session_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2455 if (cli_session_actions == MAP_FAILED)
2456 {
2457 log(0, 0, 0, 0, "Error doing mmap for cli session actions: %s\n", strerror(errno));
2458 exit(1);
2459 }
2460 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2461 cli_tunnel_actions = mmap(NULL, sizeof(struct cli_tunnel_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2462 if (cli_tunnel_actions == MAP_FAILED)
2463 {
2464 log(0, 0, 0, 0, "Error doing mmap for cli tunnel actions: %s\n", strerror(errno));
2465 exit(1);
2466 }
2467 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2468
2469 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2470 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2471 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2472 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2473
2474 // Put all the sessions on the free list marked as undefined.
2475 for (i = 1; i < MAXSESSION - 1; i++) {
2476 session[i].next = i + 1;
2477 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2478 }
2479 session[MAXSESSION - 1].next = 0;
2480 sessionfree = 1;
2481
2482 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2483 for (i = 1; i < MAXTUNNEL- 1; i++) {
2484 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2485 }
2486
2487 if (!*hostname)
2488 {
2489 char *p;
2490 // Grab my hostname unless it's been specified
2491 gethostname(hostname, sizeof(hostname));
2492 if ((p = strchr(hostname, '.'))) *p = 0;
2493 }
2494 _statistics->start_time = _statistics->last_reset = time(NULL);
2495
2496 #ifdef BGP
2497 bgp_peers = mmap(NULL, sizeof(struct bgp_peer) * BGP_NUM_PEERS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2498 if (bgp_peers == MAP_FAILED)
2499 {
2500 log(0, 0, 0, 0, "Error doing mmap for bgp: %s\n", strerror(errno));
2501 exit(1);
2502 }
2503 #endif /* BGP */
2504 }
2505
2506 void initiptables(void)
2507 {
2508 /* Flush the tables here so that we have a clean slate */
2509
2510 // Not needed. 'nat' is setup by garden.c
2511 // mangle isn't used (as throttling is done by tbf inhouse).
2512 }
2513
2514 int assign_ip_address(sessionidt s)
2515 {
2516 u32 i;
2517 int best = -1;
2518 time_t best_time = time_now;
2519 char *u = session[s].user;
2520 char reuse = 0;
2521
2522
2523 CSTAT(call_assign_ip_address);
2524
2525 for (i = 1; i < ip_pool_size; i++)
2526 {
2527 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2528 continue;
2529
2530 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2531 {
2532 best = i;
2533 reuse = 1;
2534 break;
2535 }
2536
2537 if (ip_address_pool[i].last < best_time)
2538 {
2539 best = i;
2540 if (!(best_time = ip_address_pool[i].last))
2541 break; // never used, grab this one
2542 }
2543 }
2544
2545 if (best < 0)
2546 {
2547 log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2548 return 0;
2549 }
2550
2551 session[s].ip = ip_address_pool[best].address;
2552 session[s].ip_pool_index = best;
2553 ip_address_pool[best].assigned = 1;
2554 ip_address_pool[best].last = time_now;
2555 ip_address_pool[best].session = s;
2556 if (session[s].walled_garden)
2557 /* Don't track addresses of users in walled garden (note: this
2558 means that their address isn't "sticky" even if they get
2559 un-gardened). */
2560 ip_address_pool[best].user[0] = 0;
2561 else
2562 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2563
2564 STAT(ip_allocated);
2565 log(4, ip_address_pool[best].address, s, session[s].tunnel,
2566 "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
2567
2568 return 1;
2569 }
2570
2571 void free_ip_address(sessionidt s)
2572 {
2573 int i = session[s].ip_pool_index;
2574
2575 if (!session[s].ip)
2576 return; // what the?
2577
2578 if (i < 0) // Is this actually part of the ip pool?
2579 i = 0;
2580
2581 STAT(ip_freed);
2582 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2583 session[s].ip = 0;
2584 ip_address_pool[i].assigned = 0;
2585 ip_address_pool[i].session = 0;
2586 ip_address_pool[i].last = time_now;
2587
2588
2589 CSTAT(call_free_ip_address);
2590
2591 }
2592
2593 //
2594 // Fsck the address pool against the session table.
2595 // Normally only called when we become a master.
2596 //
2597 // This isn't perfect: We aren't keep tracking of which
2598 // users used to have an IP address.
2599 //
2600 void rebuild_address_pool(void)
2601 {
2602 int i;
2603
2604 //
2605 // Zero the IP pool allocation, and build
2606 // a map from IP address to pool index.
2607 for (i = 1; i < MAXIPPOOL; ++i) {
2608 ip_address_pool[i].assigned = 0;
2609 ip_address_pool[i].session = 0;
2610 if (!ip_address_pool[i].address)
2611 continue;
2612
2613 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2614 }
2615
2616 for (i = 0; i < MAXSESSION; ++i) {
2617 int ipid;
2618 if (!session[i].ip || !session[i].tunnel)
2619 continue;
2620 ipid = - lookup_ipmap(htonl(session[i].ip));
2621
2622 if (session[i].ip_pool_index < 0) { // Not allocated out of the pool.
2623 if (ipid < 1) // Not found in the pool either? good.
2624 continue;
2625
2626 log(0, 0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2627 i, inet_toa(session[i].ip), ipid);
2628
2629 // Fall through and process it as part of the pool.
2630 }
2631
2632
2633 if (ipid > MAXIPPOOL || ipid < 0) {
2634 log(0, 0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2635 ipid = -1;
2636 session[i].ip_pool_index = ipid;
2637 continue;
2638 }
2639
2640 ip_address_pool[ipid].assigned = 1;
2641 ip_address_pool[ipid].session = i;
2642 ip_address_pool[ipid].last = time_now;
2643 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2644 session[i].ip_pool_index = ipid;
2645 cache_ipmap(session[i].ip, i); // Fix the ip map.
2646 }
2647 }
2648
2649 //
2650 // Fix the address pool to match a changed session.
2651 // (usually when the master sends us an update).
2652 void fix_address_pool(int sid)
2653 {
2654 int ipid;
2655
2656 ipid = session[sid].ip_pool_index;
2657
2658 if (ipid > ip_pool_size)
2659 return; // Ignore it. rebuild_address_pool will fix it up.
2660
2661 if (ip_address_pool[ipid].address != session[sid].ip)
2662 return; // Just ignore it. rebuild_address_pool will take care of it.
2663
2664 ip_address_pool[ipid].assigned = 1;
2665 ip_address_pool[ipid].session = sid;
2666 ip_address_pool[ipid].last = time_now;
2667 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2668 }
2669
2670 //
2671 // Add a block of addresses to the IP pool to hand out.
2672 //
2673 void add_to_ip_pool(u32 addr, u32 mask)
2674 {
2675 int i;
2676 if (mask == 0)
2677 mask = 0xffffffff; // Host route only.
2678
2679 addr &= mask;
2680
2681 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2682 return ;
2683
2684 for (i = addr ;(i & mask) == addr; ++i)
2685 {
2686 if ((i & 0xff) == 0 || (i&0xff) == 255)
2687 continue; // Skip 0 and broadcast addresses.
2688
2689 ip_address_pool[ip_pool_size].address = i;
2690 ip_address_pool[ip_pool_size].assigned = 0;
2691 ++ip_pool_size;
2692 if (ip_pool_size >= MAXIPPOOL)
2693 {
2694 log(0,0,0,0, "Overflowed IP pool adding %s\n", inet_toa(htonl(addr)) );
2695 return;
2696 }
2697 }
2698 }
2699
2700 // Initialize the IP address pool
2701 void initippool()
2702 {
2703 FILE *f;
2704 char *p;
2705 char buf[4096];
2706 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2707
2708 if (!(f = fopen(IPPOOLFILE, "r")))
2709 {
2710 log(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2711 exit(1);
2712 }
2713
2714 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2715 {
2716 char *pool = buf;
2717 buf[4095] = 0; // Force it to be zero terminated/
2718
2719 if (*buf == '#' || *buf == '\n')
2720 continue; // Skip comments / blank lines
2721 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2722 if ((p = (char *)strchr(buf, ':')))
2723 {
2724 ipt src;
2725 *p = '\0';
2726 src = inet_addr(buf);
2727 if (src == INADDR_NONE)
2728 {
2729 log(0, 0, 0, 0, "Invalid address pool IP %s\n", buf);
2730 exit(1);
2731 }
2732 // This entry is for a specific IP only
2733 if (src != config->bind_address)
2734 continue;
2735 *p = ':';
2736 pool = p+1;
2737 }
2738 if ((p = (char *)strchr(pool, '/')))
2739 {
2740 // It's a range
2741 int numbits = 0;
2742 u32 start = 0, mask = 0;
2743
2744 log(2, 0, 0, 0, "Adding IP address range %s\n", buf);
2745 *p++ = 0;
2746 if (!*p || !(numbits = atoi(p)))
2747 {
2748 log(0, 0, 0, 0, "Invalid pool range %s\n", buf);
2749 continue;
2750 }
2751 start = ntohl(inet_addr(pool));
2752 mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
2753
2754 // Add a static route for this pool
2755 log(5, 0, 0, 0, "Adding route for address pool %s/%u\n", inet_toa(htonl(start)), 32 + mask);
2756 routeset(0, start, mask, 0, 1);
2757
2758 add_to_ip_pool(start, mask);
2759 }
2760 else
2761 {
2762 // It's a single ip address
2763 add_to_ip_pool(inet_addr(pool), 0);
2764 }
2765 }
2766 fclose(f);
2767 log(1, 0, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2768 }
2769
2770 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
2771 {
2772 struct sockaddr_in snoop_addr = {0};
2773 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2774 return;
2775
2776 snoop_addr.sin_family = AF_INET;
2777 snoop_addr.sin_addr.s_addr = destination;
2778 snoop_addr.sin_port = ntohs(port);
2779
2780 log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
2781 packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
2782 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
2783 log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
2784 STAT(packets_snooped);
2785 }
2786
2787 void dump_acct_info()
2788 {
2789 char filename[1024];
2790 char timestr[64];
2791 time_t t = time(NULL);
2792 int i;
2793 FILE *f = NULL;
2794
2795
2796 CSTAT(call_dump_acct_info);
2797
2798 strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
2799 snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
2800
2801 for (i = 0; i < MAXSESSION; i++)
2802 {
2803 if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
2804 continue;
2805 if (!f)
2806 {
2807 time_t now = time(NULL);
2808 if (!(f = fopen(filename, "w")))
2809 {
2810 log(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
2811 return;
2812 }
2813 log(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
2814 fprintf(f, "# dslwatch.pl dump file V1.01\n"
2815 "# host: %s\n"
2816 "# time: %ld\n"
2817 "# uptime: %ld\n"
2818 "# format: username ip qos uptxoctets downrxoctets\n",
2819 hostname,
2820 now,
2821 now - basetime);
2822 }
2823
2824 log(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
2825 fprintf(f, "%s %s %d %u %u\n",
2826 session[i].user, // username
2827 inet_toa(htonl(session[i].ip)), // ip
2828 (session[i].throttle) ? 2 : 1, // qos
2829 (u32)session[i].cin, // uptxoctets
2830 (u32)session[i].cout); // downrxoctets
2831
2832 session[i].pin = session[i].cin = 0;
2833 session[i].pout = session[i].cout = 0;
2834 }
2835
2836 if (f) fclose(f);
2837 }
2838
2839 // Main program
2840 int main(int argc, char *argv[])
2841 {
2842 int o;
2843 int optdebug = 0;
2844
2845 _program_name = strdup(argv[0]);
2846
2847 time(&basetime); // start clock
2848
2849 // scan args
2850 while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
2851 {
2852 switch (o)
2853 {
2854 case 'd':
2855 // Double fork to detach from terminal
2856 if (fork()) exit(0);
2857 if (fork()) exit(0);
2858 break;
2859 case 'v':
2860 optdebug++;
2861 break;
2862 case 'h':
2863 snprintf(hostname, sizeof(hostname), "%s", optarg);
2864 break;
2865 case '?':
2866 default:
2867 printf("Args are:\n"
2868 "\t-d\tDetach from terminal\n"
2869 "\t-c <file>\tConfig file\n"
2870 "\t-h <hostname>\tForce hostname\n"
2871 "\t-a <address>\tUse specific address\n"
2872 "\t-v\t\tDebug\n");
2873
2874 return (0);
2875 break;
2876 }
2877 }
2878
2879 // Start the timer routine off
2880 time(&time_now);
2881 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
2882 signal(SIGALRM, sigalrm_handler);
2883 siginterrupt(SIGALRM, 0);
2884
2885 initiptables();
2886 initplugins();
2887 initdata();
2888
2889 config->debug = optdebug;
2890
2891 init_tbf();
2892 init_cli(hostname);
2893 read_config_file();
2894
2895 log(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
2896 log(0, 0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
2897 log(0, 0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
2898 {
2899 struct rlimit rlim;
2900 rlim.rlim_cur = RLIM_INFINITY;
2901 rlim.rlim_max = RLIM_INFINITY;
2902 // Remove the maximum core size
2903 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
2904 log(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
2905 // Make core dumps go to /tmp
2906 chdir("/tmp");
2907 }
2908
2909 if (config->scheduler_fifo)
2910 {
2911 int ret;
2912 struct sched_param params = {0};
2913 params.sched_priority = 1;
2914
2915 if (get_nprocs() < 2)
2916 {
2917 log(0, 0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
2918 config->scheduler_fifo = 0;
2919 }
2920 else
2921 {
2922 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
2923 {
2924 log(1, 0, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
2925 }
2926 else
2927 {
2928 log(0, 0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
2929 config->scheduler_fifo = 0;
2930 }
2931 }
2932 }
2933
2934 /* Set up the cluster communications port. */
2935 if (cluster_init(config->bind_address) < 0)
2936 exit(1);
2937
2938 #ifdef BGP
2939 signal(SIGPIPE, SIG_IGN);
2940 bgp_setup(config->as_number);
2941 bgp_add_route(config->bind_address, 0xffffffff);
2942 if (*config->bgp_peer[0])
2943 bgp_start(&bgp_peers[0], config->bgp_peer[0],
2944 config->bgp_peer_as[0], 0); /* 0 = routing disabled */
2945
2946 if (*config->bgp_peer[1])
2947 bgp_start(&bgp_peers[1], config->bgp_peer[1],
2948 config->bgp_peer_as[1], 0);
2949 #endif /* BGP */
2950
2951 inittun();
2952 log(1, 0, 0, 0, "Set up on interface %s\n", config->tundevice);
2953
2954 initudp();
2955 initrad();
2956 initippool();
2957
2958 read_state();
2959
2960 signal(SIGHUP, sighup_handler);
2961 signal(SIGTERM, sigterm_handler);
2962 signal(SIGINT, sigterm_handler);
2963 signal(SIGQUIT, sigquit_handler);
2964 signal(SIGCHLD, sigchild_handler);
2965
2966 // Prevent us from getting paged out
2967 if (config->lock_pages)
2968 {
2969 if (!mlockall(MCL_CURRENT))
2970 log(1, 0, 0, 0, "Locking pages into memory\n");
2971 else
2972 log(0, 0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
2973 }
2974
2975 alarm(1);
2976
2977 // Drop privileges here
2978 if (config->target_uid > 0 && geteuid() == 0)
2979 setuid(config->target_uid);
2980
2981 mainloop();
2982
2983 #ifdef BGP
2984 /* try to shut BGP down cleanly; with luck the sockets will be
2985 writable since we're out of the select */
2986 {
2987 int i;
2988 for (i = 0; i < BGP_NUM_PEERS; i++)
2989 if (bgp_peers[i].state == Established)
2990 bgp_stop(&bgp_peers[i]);
2991 }
2992 #endif /* BGP */
2993
2994 /* remove plugins (so cleanup code gets run) */
2995 plugins_done();
2996
2997 // Remove the PID file if we wrote it
2998 if (config->wrote_pid && *config->pid_file == '/')
2999 unlink(config->pid_file);
3000
3001 /* kill CLI children */
3002 signal(SIGTERM, SIG_IGN);
3003 kill(0, SIGTERM);
3004 return 0;
3005 }
3006
3007 void sighup_handler(int junk)
3008 {
3009 if (log_stream && log_stream != stderr)
3010 {
3011 fclose(log_stream);
3012 log_stream = NULL;
3013 }
3014
3015 read_config_file();
3016 }
3017
3018 void sigalrm_handler(int junk)
3019 {
3020 // Log current traffic stats
3021
3022 snprintf(config->bandwidth, sizeof(config->bandwidth),
3023 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3024 (udp_rx / 1024.0 / 1024.0 * 8),
3025 (eth_tx / 1024.0 / 1024.0 * 8),
3026 (eth_rx / 1024.0 / 1024.0 * 8),
3027 (udp_tx / 1024.0 / 1024.0 * 8),
3028 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3029 udp_rx_pkt, eth_rx_pkt);
3030
3031 udp_tx = udp_rx = 0;
3032 udp_rx_pkt = eth_rx_pkt = 0;
3033 eth_tx = eth_rx = 0;
3034
3035 if (config->dump_speed)
3036 printf("%s\n", config->bandwidth);
3037
3038 // Update the internal time counter
3039 time(&time_now);
3040 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3041 alarm(1);
3042
3043 {
3044 // Run timer hooks
3045 struct param_timer p = { time_now };
3046 run_plugins(PLUGIN_TIMER, &p);
3047 }
3048
3049 }
3050
3051 void sigterm_handler(int junk)
3052 {
3053 log(1, 0, 0, 0, "Shutting down cleanly\n");
3054 if (config->save_state)
3055 dump_state();
3056
3057 main_quit++;
3058 }
3059
3060 void sigquit_handler(int junk)
3061 {
3062 int i;
3063
3064 log(1, 0, 0, 0, "Shutting down without saving sessions\n");
3065 for (i = 1; i < MAXSESSION; i++)
3066 {
3067 if (session[i].opened)
3068 sessionkill(i, "L2TPNS Closing");
3069 }
3070 for (i = 1; i < MAXTUNNEL; i++)
3071 {
3072 if (tunnel[i].ip || tunnel[i].state)
3073 tunnelshutdown(i, "L2TPNS Closing");
3074 }
3075
3076 main_quit++;
3077 }
3078
3079 void sigchild_handler(int signal)
3080 {
3081 while (waitpid(-1, NULL, WNOHANG) > 0)
3082 ;
3083 }
3084
3085 void read_state()
3086 {
3087 struct stat sb;
3088 int i;
3089 ippoolt itmp;
3090 FILE *f;
3091 char magic[sizeof(DUMP_MAGIC)-1];
3092 u32 buf[2];
3093
3094 if (!config->save_state)
3095 {
3096 unlink(STATEFILE);
3097 return;
3098 }
3099
3100 if (stat(STATEFILE, &sb) < 0)
3101 {
3102 unlink(STATEFILE);
3103 return;
3104 }
3105
3106 if (sb.st_mtime < (time(NULL) - 60))
3107 {
3108 log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
3109 unlink(STATEFILE);
3110 return;
3111 }
3112
3113 f = fopen(STATEFILE, "r");
3114 unlink(STATEFILE);
3115
3116 if (!f)
3117 {
3118 log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3119 exit(1);
3120 }
3121
3122 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3123 {
3124 log(0, 0, 0, 0, "Bad state file magic\n");
3125 exit(1);
3126 }
3127
3128 log(1, 0, 0, 0, "Reading state information\n");
3129 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3130 {
3131 log(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3132 exit(1);
3133 }
3134
3135 if (buf[0] > ip_pool_size)
3136 {
3137 log(0, 0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3138 exit(1);
3139 }
3140
3141 log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
3142 for (i = 0; i < buf[0]; i++)
3143 {
3144 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3145 {
3146 log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3147 exit(1);
3148 }
3149
3150 if (itmp.address != ip_address_pool[i].address)
3151 {
3152 log(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3153 exit(1);
3154 }
3155
3156 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3157 }
3158
3159 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3160 {
3161 log(0, 0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3162 exit(1);
3163 }
3164
3165 log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3166 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3167 {
3168 log(0, 0, 0, 0, "Error reading tunnel data from state file\n");
3169 exit(1);
3170 }
3171
3172 for (i = 0; i < MAXTUNNEL; i++)
3173 {
3174 tunnel[i].controlc = 0;
3175 tunnel[i].controls = NULL;
3176 tunnel[i].controle = NULL;
3177 if (*tunnel[i].hostname)
3178 log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3179 }
3180
3181 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3182 {
3183 log(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
3184 exit(1);
3185 }
3186
3187 log(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
3188 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3189 {
3190 log(0, 0, 0, 0, "Error reading session data from state file\n");
3191 exit(1);
3192 }
3193
3194 for (i = 0; i < MAXSESSION; i++)
3195 {
3196 session[i].tbf_in = 0;
3197 session[i].tbf_out = 0;
3198 if (session[i].opened)
3199 {
3200 log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
3201 if (session[i].ip)
3202 sessionsetup(session[i].tunnel, i);
3203 }
3204 }
3205
3206 fclose(f);
3207 log(0, 0, 0, 0, "Loaded saved state information\n");
3208 }
3209
3210 void dump_state()
3211 {
3212 FILE *f;
3213 u32 buf[2];
3214
3215 if (!config->save_state)
3216 return;
3217
3218 do {
3219 if (!(f = fopen(STATEFILE, "w")))
3220 break;
3221
3222 log(1, 0, 0, 0, "Dumping state information\n");
3223
3224 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC)-1, 1, f) != 1) break;
3225
3226 log(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3227 buf[0] = ip_pool_size;
3228 buf[1] = sizeof(ippoolt);
3229 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3230 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size) break;
3231
3232 log(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3233 buf[0] = MAXTUNNEL;
3234 buf[1] = sizeof(tunnelt);
3235 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3236 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL) break;
3237
3238 log(2, 0, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3239 buf[0] = MAXSESSION;
3240 buf[1] = sizeof(sessiont);
3241 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3242 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION) break;
3243
3244 if (fclose(f) == 0) return; // OK
3245 } while (0);
3246
3247 log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3248 unlink(STATEFILE);
3249 }
3250
3251 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
3252 {
3253 MD5_CTX ctx;
3254 *challenge_response = NULL;
3255
3256 if (!*config->l2tpsecret)
3257 {
3258 log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3259 return;
3260 }
3261
3262 log(4, 0, 0, 0, " Building challenge response for CHAP request\n");
3263
3264 *challenge_response = (char *)calloc(17, 1);
3265
3266 MD5Init(&ctx);
3267 MD5Update(&ctx, &id, 1);
3268 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3269 MD5Update(&ctx, challenge, challenge_length);
3270 MD5Final(*challenge_response, &ctx);
3271
3272 return;
3273 }
3274
3275 static int facility_value(char *name)
3276 {
3277 int i;
3278 for (i = 0; facilitynames[i].c_name; i++)
3279 {
3280 if (strcmp(facilitynames[i].c_name, name) == 0)
3281 return facilitynames[i].c_val;
3282 }
3283 return 0;
3284 }
3285
3286 void update_config()
3287 {
3288 int i;
3289 static int timeout = 0;
3290 static int interval = 0;
3291
3292 // Update logging
3293 closelog();
3294 syslog_log = 0;
3295 if (log_stream)
3296 {
3297 fclose(log_stream);
3298 log_stream = NULL;
3299 }
3300 if (*config->log_filename)
3301 {
3302 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3303 {
3304 char *p = config->log_filename + 7;
3305 if (*p)
3306 {
3307 openlog("l2tpns", LOG_PID, facility_value(p));
3308 syslog_log = 1;
3309 }
3310 }
3311 else if (strchr(config->log_filename, '/') == config->log_filename)
3312 {
3313 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3314 {
3315 fseek(log_stream, 0, SEEK_END);
3316 setbuf(log_stream, NULL);
3317 }
3318 else
3319 {
3320 log_stream = stderr;
3321 setbuf(log_stream, NULL);
3322 }
3323 }
3324 }
3325 else
3326 {
3327 log_stream = stderr;
3328 setbuf(log_stream, NULL);
3329 }
3330
3331
3332 // Update radius
3333 config->numradiusservers = 0;
3334 for (i = 0; i < MAXRADSERVER; i++)
3335 if (config->radiusserver[i])
3336 {
3337 config->numradiusservers++;
3338 // Set radius port: if not set, take the port from the
3339 // first radius server. For the first radius server,
3340 // take the #defined default value from l2tpns.h
3341
3342 // test twice, In case someone works with
3343 // a secondary radius server without defining
3344 // a primary one, this will work even then.
3345 if (i>0 && !config->radiusport[i])
3346 config->radiusport[i] = config->radiusport[i-1];
3347 if (!config->radiusport[i])
3348 config->radiusport[i] = RADPORT;
3349 }
3350
3351 if (!config->numradiusservers)
3352 {
3353 log(0, 0, 0, 0, "No RADIUS servers defined!\n");
3354 }
3355
3356 config->num_radfds = 2 << RADIUS_SHIFT;
3357
3358 // Update plugins
3359 for (i = 0; i < MAXPLUGINS; i++)
3360 {
3361 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3362 continue;
3363 if (*config->plugins[i])
3364 {
3365 // Plugin added
3366 add_plugin(config->plugins[i]);
3367 }
3368 else if (*config->old_plugins[i])
3369 {
3370 // Plugin removed
3371 remove_plugin(config->old_plugins[i]);
3372 }
3373 }
3374 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3375 if (!config->cleanup_interval) config->cleanup_interval = 10;
3376 if (!config->multi_read_count) config->multi_read_count = 10;
3377 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3378 if (!*config->cluster_interface)
3379 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3380
3381 if (!config->cluster_hb_interval)
3382 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3383
3384 if (!config->cluster_hb_timeout)
3385 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3386
3387 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3388 {
3389 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3390 // late, ensure we're sufficiently larger than that
3391 int t = 4 * config->cluster_hb_interval + 11;
3392
3393 if (config->cluster_hb_timeout < t)
3394 {
3395 log(0,0,0,0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3396 config->cluster_hb_timeout = t;
3397 }
3398
3399 // Push timing changes to the slaves immediately if we're the master
3400 if (config->cluster_iam_master)
3401 cluster_heartbeat();
3402
3403 interval = config->cluster_hb_interval;
3404 timeout = config->cluster_hb_timeout;
3405 }
3406
3407 // Write PID file
3408 if (*config->pid_file == '/' && !config->wrote_pid)
3409 {
3410 FILE *f;
3411 if ((f = fopen(config->pid_file, "w")))
3412 {
3413 fprintf(f, "%d\n", getpid());
3414 fclose(f);
3415 config->wrote_pid = 1;
3416 }
3417 else
3418 {
3419 log(0, 0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3420 }
3421 }
3422
3423 config->reload_config = 0;
3424 }
3425
3426 void read_config_file()
3427 {
3428 FILE *f;
3429
3430 if (!config->config_file) return;
3431 if (!(f = fopen(config->config_file, "r"))) {
3432 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3433 return;
3434 }
3435
3436 log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
3437 cli_do_file(f);
3438 log(3, 0, 0, 0, "Done reading config file\n");
3439 fclose(f);
3440 update_config();
3441 }
3442
3443 int sessionsetup(tunnelidt t, sessionidt s)
3444 {
3445 // A session now exists, set it up
3446 ipt ip;
3447 char *user;
3448 sessionidt i;
3449 int r;
3450
3451 CSTAT(call_sessionsetup);
3452
3453
3454 log(3, session[s].ip, s, t, "Doing session setup for session\n");
3455
3456 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3457 {
3458 assign_ip_address(s);
3459 if (session[s].ip)
3460 log(3, 0, s, t, " No IP allocated. Assigned %s from pool\n",
3461 inet_toa(htonl(session[s].ip)));
3462 else
3463 log(0, 0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3464 }
3465
3466
3467 // Make sure this is right
3468 session[s].tunnel = t;
3469
3470 // zap old sessions with same IP and/or username
3471 // Don't kill gardened sessions - doing so leads to a DoS
3472 // from someone who doesn't need to know the password
3473 {
3474 ip = session[s].ip;
3475 user = session[s].user;
3476 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3477 {
3478 if (i == s) continue;
3479 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3480 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3481 sessionkill(i, "Duplicate session for users");
3482 }
3483 }
3484
3485 // Add the route for this session.
3486 //
3487 // Static IPs need to be routed. Anything else
3488 // is part of the IP address pool and is already routed,
3489 // it just needs to be added to the IP cache.
3490 if (session[s].ip_pool_index == -1) // static ip
3491 routeset(s, session[s].ip, 0, 0, 1);
3492 else
3493 cache_ipmap(session[s].ip, s);
3494
3495 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3496 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1);
3497
3498 if (!session[s].sid)
3499 {
3500 // did this session just finish radius?
3501 log(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
3502 sendipcp(t, s);
3503 session[s].sid = ++last_sid;
3504 }
3505
3506 // Run the plugin's against this new session.
3507 {
3508 struct param_new_session data = { &tunnel[t], &session[s] };
3509 run_plugins(PLUGIN_NEW_SESSION, &data);
3510 }
3511
3512 // Force throttling on or off (Actually : refresh the current throttling status)
3513 // This has the advantage of cleaning up after another throttled user who may have left
3514 // firewall rules lying around
3515 throttle_session(s, session[s].throttle);
3516
3517 session[s].last_packet = time_now;
3518
3519 {
3520 char *sessionip, *tunnelip;
3521 sessionip = strdup(inet_toa(htonl(session[s].ip)));
3522 tunnelip = strdup(inet_toa(htonl(tunnel[t].ip)));
3523 log(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
3524 session[s].user, sessionip, tunnelip, tunnel[t].hostname);
3525 if (sessionip) free(sessionip);
3526 if (tunnelip) free(tunnelip);
3527 }
3528
3529 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3530
3531 return 1; // RADIUS OK and IP allocated, done...
3532 }
3533
3534 //
3535 // This session just got dropped on us by the master or something.
3536 // Make sure our tables up up to date...
3537 //
3538 int load_session(sessionidt s, sessiont *new)
3539 {
3540 int i;
3541
3542 // Sanity checks.
3543 if (new->ip_pool_index >= MAXIPPOOL ||
3544 new->tunnel >= MAXTUNNEL) {
3545 log(0,0,s,0, "Strange session update received!\n");
3546 // FIXME! What to do here?
3547 return 0;
3548 }
3549
3550 //
3551 // Ok. All sanity checks passed. Now we're committed to
3552 // loading the new session.
3553 //
3554
3555 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3556
3557
3558 if (new->ip != session[s].ip) // Changed ip. fix up hash tables.
3559 {
3560 if (session[s].ip) // If there's an old one, remove it.
3561 {
3562 // Remove any routes if the IP has changed
3563 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3564 {
3565 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3566 session[s].route[i].ip = 0;
3567 }
3568
3569 if (session[s].ip_pool_index == -1) // static IP
3570 routeset(s, session[s].ip, 0, 0, 0);
3571 else // It's part of the IP pool, remove it manually.
3572 uncache_ipmap(session[s].ip);
3573 }
3574
3575 if (new->ip) { // If there's a new one, add it.
3576 if (new->ip_pool_index == -1)
3577 routeset(s, new->ip, 0, 0, 1);
3578 else
3579 cache_ipmap(new->ip, s);
3580 }
3581 }
3582
3583 // Update routed networks
3584 for (i = 0; i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3585 {
3586 if (new->route[i].ip == session[s].route[i].ip &&
3587 new->route[i].mask == session[s].route[i].mask)
3588 continue;
3589
3590 if (session[s].route[i].ip) // Remove the old one if it exists.
3591 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3592
3593 if (new->route[i].ip) // Add the new one if it exists.
3594 routeset(s, new->route[i].ip, new->route[i].mask, new->ip, 1);
3595 }
3596
3597 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3598 // for walking the sessions to forward byte counts to the master.
3599 config->cluster_highest_sessionid = s;
3600
3601 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3602
3603 // Do fixups into address pool.
3604 if (new->ip_pool_index != -1)
3605 fix_address_pool(s);
3606
3607 return 1;
3608 }
3609
3610 #ifdef RINGBUFFER
3611 void ringbuffer_dump(FILE *stream)
3612 {
3613 int i = ringbuffer->head;
3614
3615 while (i != ringbuffer->tail)
3616 {
3617 if (*ringbuffer->buffer[i].message)
3618 fprintf(stream, "%d-%s", ringbuffer->buffer[i].level, ringbuffer->buffer[i].message);
3619 if (++i == ringbuffer->tail) break;
3620 if (i == RINGBUFFER_SIZE) i = 0;
3621 }
3622 }
3623 #endif
3624
3625 void initplugins()
3626 {
3627 int i;
3628
3629 loaded_plugins = ll_init();
3630 // Initialize the plugins to nothing
3631 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3632 plugins[i] = ll_init();
3633 }
3634
3635 static void *open_plugin(char *plugin_name, int load)
3636 {
3637 char path[256] = "";
3638
3639 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3640 log(2, 0, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3641 return dlopen(path, RTLD_NOW);
3642 }
3643
3644 void add_plugin(char *plugin_name)
3645 {
3646 static struct pluginfuncs funcs = {
3647 _log,
3648 _log_hex,
3649 inet_toa,
3650 sessionbyuser,
3651 sessiontbysessionidt,
3652 sessionidtbysessiont,
3653 sessionkill,
3654 radiusnew,
3655 radiussend,
3656 };
3657
3658 void *p = open_plugin(plugin_name, 1);
3659 int (*initfunc)(struct pluginfuncs *);
3660 int i;
3661
3662 if (!p)
3663 {
3664 log(1, 0, 0, 0, " Plugin load failed: %s\n", dlerror());
3665 return;
3666 }
3667
3668 if (ll_contains(loaded_plugins, p))
3669 {
3670 dlclose(p);
3671 return;
3672 }
3673
3674 {
3675 int *v = dlsym(p, "__plugin_api_version");
3676 if (!v || *v != PLUGIN_API_VERSION)
3677 {
3678 log(1, 0, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
3679 dlclose(p);
3680 return;
3681 }
3682 }
3683
3684 if ((initfunc = dlsym(p, "plugin_init")))
3685 {
3686 if (!initfunc(&funcs))
3687 {
3688 log(1, 0, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
3689 dlclose(p);
3690 return;
3691 }
3692 }
3693
3694 ll_push(loaded_plugins, p);
3695
3696 for (i = 0; i < max_plugin_functions; i++)
3697 {
3698 void *x;
3699 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3700 {
3701 log(3, 0, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
3702 ll_push(plugins[i], x);
3703 }
3704 }
3705
3706 log(2, 0, 0, 0, " Loaded plugin %s\n", plugin_name);
3707 }
3708
3709 static void run_plugin_done(void *plugin)
3710 {
3711 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
3712
3713 if (donefunc)
3714 donefunc();
3715 }
3716
3717 void remove_plugin(char *plugin_name)
3718 {
3719 void *p = open_plugin(plugin_name, 0);
3720 int i;
3721
3722 if (!p)
3723 return;
3724
3725 for (i = 0; i < max_plugin_functions; i++)
3726 {
3727 void *x;
3728 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3729 ll_delete(plugins[i], x);
3730 }
3731
3732 if (ll_contains(loaded_plugins, p))
3733 {
3734 ll_delete(loaded_plugins, p);
3735 run_plugin_done(p);
3736 }
3737
3738 dlclose(p);
3739 log(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
3740 }
3741
3742 int run_plugins(int plugin_type, void *data)
3743 {
3744 int (*func)(void *data);
3745 if (!plugins[plugin_type] || plugin_type > max_plugin_functions) return 1;
3746
3747 ll_reset(plugins[plugin_type]);
3748 while ((func = ll_next(plugins[plugin_type])))
3749 {
3750 int rc;
3751 rc = func(data);
3752 if (rc == PLUGIN_RET_STOP) return 1;
3753 if (rc == PLUGIN_RET_ERROR) return 0;
3754 }
3755 return 1;
3756 }
3757
3758 void plugins_done()
3759 {
3760 void *p;
3761
3762 ll_reset(loaded_plugins);
3763 while ((p = ll_next(loaded_plugins)))
3764 run_plugin_done(p);
3765 }
3766
3767 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
3768 {
3769 char *resp;
3770 int l;
3771 struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
3772
3773
3774 if (log_stream && config->debug >= 4)
3775 {
3776 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
3777 dump_packet(buf, log_stream);
3778 }
3779
3780 resp = calloc(1400, 1);
3781 l = new_packet(PKT_RESP_ERROR, resp);
3782 *(int *)(resp + 6) = *(int *)(buf + 6);
3783
3784 param.type = ntohs(*(short *)(buf + 2));
3785 param.id = ntohl(*(int *)(buf + 6));
3786 param.data_length = ntohs(*(short *)(buf + 4)) - 10;
3787 param.data = (param.data_length > 0) ? (char *)(buf + 10) : NULL;
3788 param.response = resp;
3789 param.response_length = l;
3790
3791 run_plugins(PLUGIN_CONTROL, &param);
3792
3793 if (param.send_response)
3794 {
3795 send_packet(controlfd, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), param.response, param.response_length);
3796 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent Control packet response\n");
3797 }
3798
3799 free(resp);
3800 }
3801
3802 /*
3803 * HACK
3804 * Go through all of the tunnels and do some cleanups
3805 */
3806 void tunnel_clean()
3807 {
3808 int i;
3809
3810 log(1, 0, 0, 0, "Cleaning tunnels array\n");
3811
3812 for (i = 1; i < MAXTUNNEL; i++)
3813 {
3814 if (!tunnel[i].ip
3815 || !*tunnel[i].hostname
3816 || (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
3817 {
3818 tunnelclear(i);
3819 }
3820 }
3821 }
3822
3823 void tunnelclear(tunnelidt t)
3824 {
3825 if (!t) return;
3826 memset(&tunnel[t], 0, sizeof(tunnel[t]));
3827 tunnel[t].state = TUNNELFREE;
3828 }
3829
3830 tunnelidt new_tunnel()
3831 {
3832 tunnelidt i;
3833 for (i = 1; i < MAXTUNNEL; i++)
3834 {
3835 if (tunnel[i].state == TUNNELFREE)
3836 {
3837 log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
3838 if (i > config->cluster_highest_tunnelid)
3839 config->cluster_highest_tunnelid = i;
3840 return i;
3841 }
3842 }
3843 log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
3844 return 0;
3845 }
3846
3847 //
3848 // We're becoming the master. Do any required setup..
3849 //
3850 // This is principally telling all the plugins that we're
3851 // now a master, and telling them about all the sessions
3852 // that are active too..
3853 //
3854 void become_master(void)
3855 {
3856 int s;
3857 run_plugins(PLUGIN_BECOME_MASTER, NULL);
3858
3859 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3860 if (!session[s].tunnel) // Not an in-use session.
3861 continue;
3862
3863 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
3864 }
3865 }
3866
3867
3868
3869 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
3870 {
3871 int s, i;
3872 int count = 0;
3873 int buckets[64];
3874
3875 if (CLI_HELP_REQUESTED)
3876 return CLI_HELP_NO_ARGS;
3877
3878 time(&time_now);
3879 for (i = 0; i < 64;++i) buckets[i] = 0;
3880
3881 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3882 int idle;
3883 if (!session[s].tunnel)
3884 continue;
3885
3886 idle = time_now - session[s].last_packet;
3887 idle /= 5 ; // In multiples of 5 seconds.
3888 if (idle < 0)
3889 idle = 0;
3890 if (idle > 63)
3891 idle = 63;
3892
3893 ++count;
3894 ++buckets[idle];
3895 }
3896
3897 for (i = 0; i < 63; ++i) {
3898 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
3899 }
3900 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
3901 cli_print(cli, "%d total sessions open.", count);
3902 return CLI_OK;
3903 }
3904
3905 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
3906 {
3907 int s, i;
3908 int count = 0;
3909 int buckets[64];
3910
3911 if (CLI_HELP_REQUESTED)
3912 return CLI_HELP_NO_ARGS;
3913
3914 time(&time_now);
3915 for (i = 0; i < 64;++i) buckets[i] = 0;
3916
3917 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3918 int open = 0, d;
3919 if (!session[s].tunnel)
3920 continue;
3921
3922 d = time_now - session[s].opened;
3923 if (d < 0)
3924 d = 0;
3925 while (d > 1 && open < 32) {
3926 ++open;
3927 d >>= 1; // half.
3928 }
3929 ++count;
3930 ++buckets[open];
3931 }
3932
3933 s = 1;
3934 for (i = 0; i < 30; ++i) {
3935 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
3936 s <<= 1;
3937 }
3938 cli_print(cli, "%d total sessions open.", count);
3939 return CLI_OK;
3940 }