c3443bd51672577264f85a42533ed9be3f8b4a0d
[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 1.13 2004/07/11 07:57:35 bodea 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("l2tp_secret", l2tpsecret, STRING),
98 CONFIG("primary_dns", default_dns1, IP),
99 CONFIG("secondary_dns", default_dns2, IP),
100 CONFIG("save_state", save_state, BOOL),
101 CONFIG("primary_radius", radiusserver[0], IP),
102 CONFIG("secondary_radius", radiusserver[1], IP),
103 CONFIG("radius_accounting", radius_accounting, BOOL),
104 CONFIG("radius_secret", radiussecret, STRING),
105 CONFIG("bind_address", bind_address, IP),
106 CONFIG("send_garp", send_garp, BOOL),
107 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
108 CONFIG("accounting_dir", accounting_dir, STRING),
109 CONFIG("setuid", target_uid, INT),
110 CONFIG("dump_speed", dump_speed, BOOL),
111 CONFIG("cleanup_interval", cleanup_interval, INT),
112 CONFIG("multi_read_count", multi_read_count, INT),
113 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
114 CONFIG("icmp_rate", icmp_rate, INT),
115 CONFIG("cluster_address", cluster_address, IP),
116 CONFIG("cluster_interface", cluster_interface, STRING),
117 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
118 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
119 #ifdef BGP
120 CONFIG("as_number", as_number, SHORT),
121 CONFIG("bgp_peer1", bgp_peer[0], STRING),
122 CONFIG("bgp_peer1_as", bgp_peer_as[0], SHORT),
123 CONFIG("bgp_peer2", bgp_peer[1], STRING),
124 CONFIG("bgp_peer2_as", bgp_peer_as[1], SHORT),
125 #endif /* BGP */
126 { NULL, 0, 0, 0 },
127 };
128
129 char *plugin_functions[] = {
130 NULL,
131 "plugin_pre_auth",
132 "plugin_post_auth",
133 "plugin_packet_rx",
134 "plugin_packet_tx",
135 "plugin_timer",
136 "plugin_new_session",
137 "plugin_kill_session",
138 "plugin_control",
139 "plugin_radius_response",
140 "plugin_become_master",
141 "plugin_new_session_master",
142 };
143
144 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
145
146 tunnelt *tunnel = NULL; // Array of tunnel structures.
147 sessiont *session = NULL; // Array of session structures.
148 sessioncountt *sess_count = NULL; // Array of partial per-session traffic counters.
149 radiust *radius = NULL; // Array of radius structures.
150 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
151 controlt *controlfree = 0;
152 struct Tstats *_statistics = NULL;
153 #ifdef RINGBUFFER
154 struct Tringbuffer *ringbuffer = NULL;
155 #endif
156
157 void sigalrm_handler(int);
158 void sighup_handler(int);
159 void sigterm_handler(int);
160 void sigquit_handler(int);
161 void sigchild_handler(int);
162 void read_config_file();
163 void read_state();
164 void dump_state();
165 void tunnel_clean();
166 tunnelidt new_tunnel();
167 void update_config();
168
169 static void cache_ipmap(ipt ip, int s);
170 static void uncache_ipmap(ipt ip);
171
172 // return internal time (10ths since process startup)
173 clockt now(void)
174 {
175 struct timeval t;
176 gettimeofday(&t, 0);
177 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
178 }
179
180 // work out a retry time based on try number
181 // This is a straight bounded exponential backoff.
182 // Maximum re-try time is 32 seconds. (2^5).
183 clockt backoff(u8 try)
184 {
185 if (try > 5) try = 5; // max backoff
186 return now() + 10 * (1 << try);
187 }
188
189
190 //
191 // Log a debug message.
192 //
193 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
194 {
195 static char message[65536] = {0};
196 static char message2[65536] = {0};
197 va_list ap;
198
199 #ifdef RINGBUFFER
200 if (ringbuffer)
201 {
202 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
203 ringbuffer->tail = 0;
204 if (ringbuffer->tail == ringbuffer->head)
205 if (++ringbuffer->head >= RINGBUFFER_SIZE)
206 ringbuffer->head = 0;
207
208 ringbuffer->buffer[ringbuffer->tail].level = level;
209 ringbuffer->buffer[ringbuffer->tail].address = address;
210 ringbuffer->buffer[ringbuffer->tail].session = s;
211 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
212 va_start(ap, format);
213 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
214 va_end(ap);
215 }
216 #endif
217
218 if (config->debug < level) return;
219
220 va_start(ap, format);
221 if (log_stream)
222 {
223 vsnprintf(message2, 65535, format, ap);
224 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
225 fprintf(log_stream, "%s", message);
226 }
227 else if (syslog_log)
228 {
229 vsnprintf(message2, 65535, format, ap);
230 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
231 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
232 }
233 va_end(ap);
234 }
235
236 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize)
237 {
238 int i, j;
239 const u8 *d = (const u8 *)data;
240
241 if (config->debug < level) return;
242
243 // No support for log_hex to syslog
244 if (log_stream)
245 {
246 log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
247 setvbuf(log_stream, NULL, _IOFBF, 16384);
248
249 for (i = 0; i < maxsize; )
250 {
251 fprintf(log_stream, "%4X: ", i);
252 for (j = i; j < maxsize && j < (i + 16); j++)
253 {
254 fprintf(log_stream, "%02X ", d[j]);
255 if (j == i + 7)
256 fputs(": ", log_stream);
257 }
258
259 for (; j < i + 16; j++)
260 {
261 fputs(" ", log_stream);
262 if (j == i + 7)
263 fputs(": ", log_stream);
264 }
265
266 fputs(" ", log_stream);
267 for (j = i; j < maxsize && j < (i + 16); j++)
268 {
269 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
270 fputc(d[j], log_stream);
271 else
272 fputc('.', log_stream);
273
274 if (j == i + 7)
275 fputs(" ", log_stream);
276 }
277
278 i = j;
279 fputs("\n", log_stream);
280 }
281
282 fflush(log_stream);
283 setbuf(log_stream, NULL);
284 }
285 }
286
287
288 // Add a route
289 //
290 // This adds it to the routing table, advertises it
291 // via iBGP if enabled, and stuffs it into the
292 // 'sessionbyip' cache.
293 //
294 // 'ip' and 'mask' must be in _host_ order.
295 //
296 void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
297 {
298 struct rtentry r;
299 int i;
300
301 if (!mask) mask = 0xffffffff;
302
303 ip &= mask; // Force the ip to be the first one in the route.
304
305 memset(&r, 0, sizeof(r));
306 r.rt_dev = config->tundevice;
307 r.rt_dst.sa_family = AF_INET;
308 *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
309 r.rt_gateway.sa_family = AF_INET;
310 *(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
311 r.rt_genmask.sa_family = AF_INET;
312 *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
313 r.rt_flags = (RTF_UP | RTF_STATIC);
314 if (gw)
315 r.rt_flags |= RTF_GATEWAY;
316 else if (mask == 0xffffffff)
317 r.rt_flags |= RTF_HOST;
318
319 log(1, ip, 0, 0, "Route %s %u.%u.%u.%u/%u.%u.%u.%u %u.%u.%u.%u\n",
320 add ? "add" : "del",
321 ip >> 24, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff,
322 mask >> 24, mask >> 16 & 0xff, mask >> 8 & 0xff, mask & 0xff,
323 gw >> 24, gw >> 16 & 0xff, gw >> 8 & 0xff, gw & 0xff);
324
325 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
326 log(0, 0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
327
328 #ifdef BGP
329 if (add)
330 bgp_add_route(htonl(ip), htonl(mask));
331 else
332 bgp_del_route(htonl(ip), htonl(mask));
333 #endif /* BGP */
334
335 // Add/Remove the IPs to the 'sessionbyip' cache.
336 // Note that we add the zero address in the case of
337 // a network route. Roll on CIDR.
338
339 // Note that 's == 0' implies this is the address pool.
340 // We still cache it here, because it will pre-fill
341 // the malloc'ed tree.
342
343 if (s)
344 {
345 if (!add) // Are we deleting a route?
346 s = 0; // Caching the session as '0' is the same as uncaching.
347
348 for (i = ip; (i&mask) == (ip&mask) ; ++i)
349 cache_ipmap(i, s);
350 }
351 }
352
353 //
354 // Set up TUN interface
355 void inittun(void)
356 {
357 struct ifreq ifr;
358 struct sockaddr_in sin = {0};
359 memset(&ifr, 0, sizeof(ifr));
360 ifr.ifr_flags = IFF_TUN;
361
362 tunfd = open(TUNDEVICE, O_RDWR);
363 if (tunfd < 0)
364 { // fatal
365 log(0, 0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
366 exit(1);
367 }
368 {
369 int flags = fcntl(tunfd, F_GETFL, 0);
370 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
371 }
372 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
373 {
374 log(0, 0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
375 exit(1);
376 }
377 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
378 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
379 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
380
381 sin.sin_family = AF_INET;
382 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
383 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
384
385 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
386 {
387 log(0, 0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
388 exit(1);
389 }
390 /* Bump up the qlen to deal with bursts from the network */
391 ifr.ifr_qlen = 1000;
392 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
393 {
394 log(0, 0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
395 exit(1);
396 }
397 ifr.ifr_flags = IFF_UP;
398 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
399 {
400 log(0, 0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
401 exit(1);
402 }
403 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
404 {
405 log(0, 0, 0, 0, "Error setting tun ifindex: %s\n", strerror(errno));
406 exit(1);
407 }
408 tunidx = ifr.ifr_ifindex;
409 }
410
411 // set up UDP port
412 void initudp(void)
413 {
414 int on = 1;
415 struct sockaddr_in addr;
416
417 // Tunnel
418 memset(&addr, 0, sizeof(addr));
419 addr.sin_family = AF_INET;
420 addr.sin_port = htons(L2TPPORT);
421 addr.sin_addr.s_addr = config->bind_address;
422 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
423 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
424 {
425 int flags = fcntl(udpfd, F_GETFL, 0);
426 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
427 }
428 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
429 {
430 log(0, 0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
431 exit(1);
432 }
433 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
434
435 // Control
436 memset(&addr, 0, sizeof(addr));
437 addr.sin_family = AF_INET;
438 addr.sin_port = htons(1702);
439 controlfd = socket(AF_INET, SOCK_DGRAM, 17);
440 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
441 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
442 {
443 log(0, 0, 0, 0, "Error in control bind: %s\n", strerror(errno));
444 exit(1);
445 }
446 }
447
448 //
449 // Find session by IP, < 1 for not found
450 //
451 // Confusingly enough, this 'ip' must be
452 // in _network_ order. This being the common
453 // case when looking it up from IP packet headers.
454 //
455 // We actually use this cache for two things.
456 // #1. For used IP addresses, this maps to the
457 // session ID that it's used by.
458 // #2. For un-used IP addresses, this maps to the
459 // index into the pool table that contains that
460 // IP address.
461 //
462
463 int lookup_ipmap(ipt ip)
464 {
465 u8 *a = (u8 *)&ip;
466 char **d = (char **) ip_hash;
467 int s;
468
469 if (!(d = (char **) d[(size_t) *a++])) return 0;
470 if (!(d = (char **) d[(size_t) *a++])) return 0;
471 if (!(d = (char **) d[(size_t) *a++])) return 0;
472
473 s = (ipt) d[(size_t) *a];
474 return s;
475 }
476
477 sessionidt sessionbyip(ipt ip)
478 {
479 int s = lookup_ipmap(ip);
480 CSTAT(call_sessionbyip);
481
482 if (s > 0 && s < MAXSESSION && session[s].tunnel)
483 return s;
484 return 0;
485 }
486
487 //
488 // Take an IP address in HOST byte order and
489 // add it to the sessionid by IP cache.
490 //
491 // (It's actually cached in network order)
492 //
493 static void cache_ipmap(ipt ip, int s)
494 {
495 ipt nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char*)(&ip))[0]
496 u8 *a = (u8 *) &nip;
497 char **d = (char **) ip_hash;
498 int i;
499
500 for (i = 0; i < 3; i++)
501 {
502 if (!d[(size_t) a[i]])
503 {
504 if (!(d[(size_t) a[i]] = calloc(256, sizeof (void *))))
505 return;
506 }
507
508 d = (char **) d[(size_t) a[i]];
509 }
510
511 d[(size_t) a[3]] = (char *)((int)s);
512
513 if (s > 0)
514 log(4, ip, s, session[s].tunnel, "Caching ip address %s\n", inet_toa(nip));
515 else if (s == 0)
516 log(4, ip, 0, 0, "Un-caching ip address %s\n", inet_toa(nip));
517 // else a map to an ip pool index.
518 }
519
520 static void uncache_ipmap(ipt ip)
521 {
522 cache_ipmap(ip, 0); // Assign it to the NULL session.
523 }
524
525 //
526 // CLI list to dump current ipcache.
527 //
528 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
529 {
530 char **d = (char **) ip_hash, **e, **f, **g;
531 int i, j, k, l;
532 int count = 0;
533
534 if (CLI_HELP_REQUESTED)
535 return CLI_HELP_NO_ARGS;
536
537 cli_print(cli, "%7s %s", "Sess#", "IP Address");
538
539 for (i = 0; i < 256; ++i) {
540 if (!d[i]) continue;
541 e = (char**) d[i];
542 for (j = 0; j < 256; ++j) {
543 if (!e[j]) continue;
544 f = (char**) e[j];
545 for (k = 0; k < 256; ++k) {
546 if (!f[k]) continue;
547 g = (char**)f[k];
548 for (l = 0; l < 256; ++l) {
549 if (!g[l]) continue;
550 cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
551 ++count;
552 }
553 }
554 }
555 }
556 cli_print(cli, "%d entries in cache", count);
557 return CLI_OK;
558 }
559
560
561 // Find session by username, 0 for not found
562 // walled garden users aren't authenticated, so the username is
563 // reasonably useless. Ignore them to avoid incorrect actions
564 //
565 // This is VERY inefficent. Don't call it often. :)
566 //
567 sessionidt sessionbyuser(char *username)
568 {
569 int s;
570 CSTAT(call_sessionbyuser);
571
572 for (s = 1; s < MAXSESSION ; ++s) {
573 if (session[s].walled_garden)
574 continue; // Skip walled garden users.
575
576 if (!strncmp(session[s].user, username, 128))
577 return s;
578
579 }
580 return 0; // Not found.
581 }
582
583 void send_garp(ipt ip)
584 {
585 int s;
586 struct ifreq ifr;
587 u8 mac[6];
588
589 s = socket(PF_INET, SOCK_DGRAM, 0);
590 if (s < 0)
591 {
592 log(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
593 return;
594 }
595 memset(&ifr, 0, sizeof(ifr));
596 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
597 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
598 {
599 log(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
600 close(s);
601 return;
602 }
603 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
604 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
605 {
606 log(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
607 close(s);
608 return;
609 }
610 close(s);
611 sendarp(ifr.ifr_ifindex, mac, ip);
612 }
613
614 // Find session by username, 0 for not found
615 sessiont *sessiontbysessionidt(sessionidt s)
616 {
617 if (!s || s > MAXSESSION) return NULL;
618 return &session[s];
619 }
620
621 sessionidt sessionidtbysessiont(sessiont *s)
622 {
623 sessionidt val = s-session;
624 if (s < session || val > MAXSESSION) return 0;
625 return val;
626 }
627
628 // actually send a control message for a specific tunnel
629 void tunnelsend(u8 * buf, u16 l, tunnelidt t)
630 {
631 struct sockaddr_in addr;
632
633 CSTAT(call_tunnelsend);
634
635 if (!t)
636 {
637 static int backtrace_count = 0;
638 log(0, 0, 0, t, "tunnelsend called with 0 as tunnel id\n");
639 STAT(tunnel_tx_errors);
640 log_backtrace(backtrace_count, 5)
641 return;
642 }
643
644 if (!tunnel[t].ip)
645 {
646 static int backtrace_count = 0;
647 log(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
648 log_backtrace(backtrace_count, 5)
649 STAT(tunnel_tx_errors);
650 return;
651 }
652 memset(&addr, 0, sizeof(addr));
653 addr.sin_family = AF_INET;
654 *(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
655 addr.sin_port = htons(tunnel[t].port);
656
657 // sequence expected, if sequence in message
658 if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
659
660 // If this is a control message, deal with retries
661 if (*buf & 0x80)
662 {
663 tunnel[t].last = time_now; // control message sent
664 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
665 if (tunnel[t].try > 1)
666 {
667 STAT(tunnel_retries);
668 log(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
669 }
670 }
671
672 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
673 {
674 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",
675 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
676 STAT(tunnel_tx_errors);
677 return;
678 }
679
680 log_hex(5, "Send Tunnel Data", buf, l);
681 STAT(tunnel_tx_packets);
682 INC_STAT(tunnel_tx_bytes, l);
683 }
684
685 //
686 // Tiny helper function to write data to
687 // the 'tun' device.
688 //
689 int tun_write(u8 * data, int size)
690 {
691 return write(tunfd, data, size);
692 }
693
694 // process outgoing (to tunnel) IP
695 //
696 void processipout(u8 * buf, int len)
697 {
698 sessionidt s;
699 sessiont *sp;
700 tunnelidt t;
701 ipt ip;
702
703 char * data = buf; // Keep a copy of the originals.
704 int size = len;
705
706 u8 b[MAXETHER + 20];
707
708 CSTAT(call_processipout);
709
710 if (len < MIN_IP_SIZE)
711 {
712 log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
713 STAT(tunnel_tx_errors);
714 return;
715 }
716 if (len >= MAXETHER)
717 {
718 log(1, 0, 0, 0, "Oversize IP packet %d bytes\n", len);
719 STAT(tunnel_tx_errors);
720 return;
721 }
722
723 // Skip the tun header
724 buf += 4;
725 len -= 4;
726
727 // Got an IP header now
728 if (*(u8 *)(buf) >> 4 != 4)
729 {
730 log(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
731 return;
732 }
733
734 ip = *(u32 *)(buf + 16);
735 if (!(s = sessionbyip(ip)))
736 {
737 // Is this a packet for a session that doesn't exist?
738 static int rate = 0; // Number of ICMP packets we've sent this second.
739 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
740
741 if (last != time_now) {
742 last = time_now;
743 rate = 0;
744 }
745
746 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
747 {
748 log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
749 host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
750 }
751 return;
752 }
753 t = session[s].tunnel;
754 sp = &session[s];
755
756 if (sp->tbf_out)
757 {
758 // Are we throttling this session?
759 if (config->cluster_iam_master)
760 tbf_queue_packet(sp->tbf_out, data, size);
761 else
762 master_throttle_packet(sp->tbf_out, data, size);
763 return;
764 }
765 else if (sp->walled_garden && !config->cluster_iam_master)
766 {
767 // We are walled-gardening this
768 master_garden_packet(s, data, size);
769 return;
770 }
771
772 // Snooping this session, send it to intercept box
773 if (sp->snoop_ip && sp->snoop_port)
774 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
775
776 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
777
778 // Add on L2TP header
779 {
780 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
781 if (!p) {
782 log(3, session[s].ip, s, t, "failed to send packet in processipout.\n");
783 return;
784 }
785 tunnelsend(b, len + (p-b), t); // send it...
786 }
787
788 sp->cout += len; // byte count
789 sp->total_cout += len; // byte count
790 sp->pout++;
791 udp_tx += len;
792 sess_count[s].cout += len; // To send to master..
793 }
794
795 //
796 // Helper routine for the TBF filters.
797 // Used to send queued data in to the user!
798 //
799 void send_ipout(sessionidt s, u8 *buf, int len)
800 {
801 sessiont *sp;
802 tunnelidt t;
803 ipt ip;
804
805 u8 b[MAXETHER + 20];
806
807 if (len < 0 || len > MAXETHER) {
808 log(1,0,0,0, "Odd size IP packet: %d bytes\n", len);
809 return;
810 }
811
812 // Skip the tun header
813 buf += 4;
814 len -= 4;
815
816 ip = *(u32 *)(buf + 16);
817
818 if (!session[s].ip)
819 return;
820 t = session[s].tunnel;
821 sp = &session[s];
822
823 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
824
825 // Snooping this session.
826 if (sp->snoop_ip && sp->snoop_port)
827 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
828
829 // Add on L2TP header
830 {
831 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
832 if (!p) {
833 log(3, session[s].ip, s, t, "failed to send packet in send_ipout.\n");
834 return;
835 }
836 tunnelsend(b, len + (p-b), t); // send it...
837 }
838 sp->cout += len; // byte count
839 sp->total_cout += len; // byte count
840 sp->pout++;
841 udp_tx += len;
842 sess_count[s].cout += len; // To send to master..
843 }
844
845 // add an AVP (16 bit)
846 void control16(controlt * c, u16 avp, u16 val, u8 m)
847 {
848 u16 l = (m ? 0x8008 : 0x0008);
849 *(u16 *) (c->buf + c->length + 0) = htons(l);
850 *(u16 *) (c->buf + c->length + 2) = htons(0);
851 *(u16 *) (c->buf + c->length + 4) = htons(avp);
852 *(u16 *) (c->buf + c->length + 6) = htons(val);
853 c->length += 8;
854 }
855
856 // add an AVP (32 bit)
857 void control32(controlt * c, u16 avp, u32 val, u8 m)
858 {
859 u16 l = (m ? 0x800A : 0x000A);
860 *(u16 *) (c->buf + c->length + 0) = htons(l);
861 *(u16 *) (c->buf + c->length + 2) = htons(0);
862 *(u16 *) (c->buf + c->length + 4) = htons(avp);
863 *(u32 *) (c->buf + c->length + 6) = htonl(val);
864 c->length += 10;
865 }
866
867 // add an AVP (32 bit)
868 void controls(controlt * c, u16 avp, char *val, u8 m)
869 {
870 u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
871 *(u16 *) (c->buf + c->length + 0) = htons(l);
872 *(u16 *) (c->buf + c->length + 2) = htons(0);
873 *(u16 *) (c->buf + c->length + 4) = htons(avp);
874 memcpy(c->buf + c->length + 6, val, strlen(val));
875 c->length += 6 + strlen(val);
876 }
877
878 // add a binary AVP
879 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
880 {
881 u16 l = ((m ? 0x8000 : 0) + len + 6);
882 *(u16 *) (c->buf + c->length + 0) = htons(l);
883 *(u16 *) (c->buf + c->length + 2) = htons(0);
884 *(u16 *) (c->buf + c->length + 4) = htons(avp);
885 memcpy(c->buf + c->length + 6, val, len);
886 c->length += 6 + len;
887 }
888
889 // new control connection
890 controlt *controlnew(u16 mtype)
891 {
892 controlt *c;
893 if (!controlfree)
894 c = malloc(sizeof(controlt));
895 else
896 {
897 c = controlfree;
898 controlfree = c->next;
899 }
900 assert(c);
901 c->next = 0;
902 *(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
903 c->length = 12;
904 control16(c, 0, mtype, 1);
905 return c;
906 }
907
908 // send zero block if nothing is waiting
909 // (ZLB send).
910 void controlnull(tunnelidt t)
911 {
912 u8 buf[12];
913 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
914 return;
915
916 *(u16 *) (buf + 0) = htons(0xC802); // flags/ver
917 *(u16 *) (buf + 2) = htons(12); // length
918 *(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
919 *(u16 *) (buf + 6) = htons(0); // session
920 *(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
921 *(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
922 tunnelsend(buf, 12, t);
923 }
924
925 // add a control message to a tunnel, and send if within window
926 void controladd(controlt * c, tunnelidt t, sessionidt s)
927 {
928 *(u16 *) (c->buf + 2) = htons(c->length); // length
929 *(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
930 *(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
931 *(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
932 tunnel[t].ns++; // advance sequence
933 // link in message in to queue
934 if (tunnel[t].controlc)
935 tunnel[t].controle->next = c;
936 else
937 tunnel[t].controls = c;
938 tunnel[t].controle = c;
939 tunnel[t].controlc++;
940 // send now if space in window
941 if (tunnel[t].controlc <= tunnel[t].window)
942 {
943 tunnel[t].try = 0; // first send
944 tunnelsend(c->buf, c->length, t);
945 }
946 }
947
948 //
949 // Throttle or Unthrottle a session
950 //
951 // Throttle the data folling through a session
952 // to be no more than 'throttle' kbit/sec each way.
953 //
954 int throttle_session(sessionidt s, int throttle)
955 {
956 if (!session[s].tunnel)
957 return 0; // No-one home.
958
959 if (!*session[s].user)
960 return 0; // User not logged in
961
962 if (throttle) {
963 if (session[s].tbf_in || session[s].tbf_out) {
964 if (throttle == session[s].throttle)
965 return 1;
966
967 // Currently throttled but the rate is changing.
968
969 free_tbf(session[s].tbf_in);
970 free_tbf(session[s].tbf_out);
971 }
972
973 session[s].tbf_in = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipin);
974 session[s].tbf_out = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipout);
975
976 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
977 session[s].throttle = throttle;
978 cluster_send_session(s);
979 }
980
981 return 1;
982 }
983
984 // else Unthrottling.
985
986 if (!session[s].tbf_in && !session[s].tbf_out && !session[s].throttle)
987 return 0;
988
989 free_tbf(session[s].tbf_in);
990 session[s].tbf_in = 0;
991
992 free_tbf(session[s].tbf_out);
993 session[s].tbf_out = 0;
994
995 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
996 session[s].throttle = throttle;
997 cluster_send_session(s);
998 }
999
1000 return 0;
1001 }
1002
1003 // start tidy shutdown of session
1004 void sessionshutdown(sessionidt s, char *reason)
1005 {
1006 int dead = session[s].die;
1007 int walled_garden = session[s].walled_garden;
1008
1009
1010 CSTAT(call_sessionshutdown);
1011
1012 if (!session[s].tunnel)
1013 {
1014 log(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1015 return; // not a live session
1016 }
1017
1018 if (!dead)
1019 log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1020
1021 session[s].die = now() + 150; // Clean up in 15 seconds
1022
1023 {
1024 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1025 run_plugins(PLUGIN_KILL_SESSION, &data);
1026 }
1027
1028 // RADIUS Stop message
1029 if (session[s].opened && !walled_garden && !dead) {
1030 u16 r = session[s].radius;
1031 if (!r)
1032 {
1033 if (!(r = radiusnew(s)))
1034 {
1035 log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1036 STAT(radius_overflow);
1037 }
1038 else
1039 {
1040 int n;
1041 for (n = 0; n < 15; n++)
1042 radius[r].auth[n] = rand();
1043 }
1044 }
1045 if (r && radius[r].state != RADIUSSTOP)
1046 radiussend(r, RADIUSSTOP); // stop, if not already trying
1047 }
1048
1049 if (session[s].ip)
1050 { // IP allocated, clear and unroute
1051 int r;
1052 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1053 {
1054 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 0);
1055 session[s].route[r].ip = 0;
1056 }
1057
1058 if (session[s].ip_pool_index == -1) // static ip
1059 {
1060 routeset(s, session[s].ip, 0, 0, 0); // Delete route.
1061 session[s].ip = 0;
1062 }
1063 else
1064 free_ip_address(s);
1065
1066 if (session[s].throttle) // Unthrottle if throttled.
1067 throttle_session(s, 0);
1068 }
1069 { // Send CDN
1070 controlt *c = controlnew(14); // sending CDN
1071 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1072 control16(c, 14, s, 1); // assigned session (our end)
1073 controladd(c, session[s].tunnel, s); // send the message
1074 }
1075 cluster_send_session(s);
1076 }
1077
1078 void sendipcp(tunnelidt t, sessionidt s)
1079 {
1080 u8 buf[MAXCONTROL];
1081 u16 r = session[s].radius;
1082 u8 *q;
1083
1084 CSTAT(call_sendipcp);
1085
1086 if (!r)
1087 r = radiusnew(s);
1088
1089 if (radius[r].state != RADIUSIPCP)
1090 {
1091 radius[r].state = RADIUSIPCP;
1092 radius[r].try = 0;
1093 }
1094
1095 radius[r].retry = backoff(radius[r].try++);
1096 if (radius[r].try > 10)
1097 {
1098 radiusclear(r, s); // Clear radius session.
1099 sessionshutdown(s, "No reply on IPCP");
1100 return;
1101 }
1102
1103 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1104 if (!q) {
1105 log(3, session[s].ip, s, t, "failed to send packet in sendipcp.\n");
1106 return;
1107 }
1108
1109 *q = ConfigReq;
1110 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1111 *(u16 *) (q + 2) = htons(10);
1112 q[4] = 3;
1113 q[5] = 6;
1114 *(u32 *) (q + 6) = config->bind_address; // send my IP
1115 tunnelsend(buf, 10 + (q - buf), t); // send it
1116 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1117 }
1118
1119 // kill a session now
1120 void sessionkill(sessionidt s, char *reason)
1121 {
1122
1123 CSTAT(call_sessionkill);
1124
1125 session[s].die = now();
1126 sessionshutdown(s, reason); // close radius/routes, etc.
1127 if (session[s].radius)
1128 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1129
1130 log(2, 0, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1131
1132 throttle_session(s, 0); // Force session to be un-throttle. Free'ing TBF structures.
1133
1134 memset(&session[s], 0, sizeof(session[s]));
1135 session[s].tunnel = T_FREE; // Mark it as free.
1136 session[s].next = sessionfree;
1137 sessionfree = s;
1138 cli_session_actions[s].action = 0;
1139 cluster_send_session(s);
1140 }
1141
1142 // kill a tunnel now
1143 void tunnelkill(tunnelidt t, char *reason)
1144 {
1145 sessionidt s;
1146 controlt *c;
1147
1148 CSTAT(call_tunnelkill);
1149
1150 tunnel[t].state = TUNNELDIE;
1151
1152 // free control messages
1153 while ((c = tunnel[t].controls))
1154 {
1155 controlt * n = c->next;
1156 tunnel[t].controls = n;
1157 tunnel[t].controlc--;
1158 c->next = controlfree;
1159 controlfree = c;
1160 }
1161 // kill sessions
1162 for (s = 1; s < MAXSESSION; s++)
1163 if (session[s].tunnel == t)
1164 sessionkill(s, reason);
1165
1166 // free tunnel
1167 tunnelclear(t);
1168 log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
1169 cli_tunnel_actions[s].action = 0;
1170 cluster_send_tunnel(t);
1171 }
1172
1173 // shut down a tunnel cleanly
1174 void tunnelshutdown(tunnelidt t, char *reason)
1175 {
1176 sessionidt s;
1177
1178 CSTAT(call_tunnelshutdown);
1179
1180 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1181 {
1182 // never set up, can immediately kill
1183 tunnelkill(t, reason);
1184 return;
1185 }
1186 log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1187
1188 // close session
1189 for (s = 1; s < MAXSESSION; s++)
1190 if (session[s].tunnel == t)
1191 sessionkill(s, reason);
1192
1193 tunnel[t].state = TUNNELDIE;
1194 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1195 cluster_send_tunnel(t);
1196 // TBA - should we wait for sessions to stop?
1197 { // Send StopCCN
1198 controlt *c = controlnew(4); // sending StopCCN
1199 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message
1200 control16(c, 9, t, 1); // assigned tunnel (our end)
1201 controladd(c, t, 0); // send the message
1202 }
1203 }
1204
1205 // read and process packet on tunnel (UDP)
1206 void processudp(u8 * buf, int len, struct sockaddr_in *addr)
1207 {
1208 char *chapresponse = NULL;
1209 u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
1210 u8 *p = buf + 2;
1211
1212
1213 CSTAT(call_processudp);
1214
1215 udp_rx += len;
1216 udp_rx_pkt++;
1217 log_hex(5, "UDP Data", buf, len);
1218 STAT(tunnel_rx_packets);
1219 INC_STAT(tunnel_rx_bytes, len);
1220 if (len < 6)
1221 {
1222 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
1223 STAT(tunnel_rx_errors);
1224 return;
1225 }
1226 if ((buf[1] & 0x0F) != 2)
1227 {
1228 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1229 STAT(tunnel_rx_errors);
1230 return;
1231 }
1232 if (*buf & 0x40)
1233 { // length
1234 l = ntohs(*(u16 *) p);
1235 p += 2;
1236 }
1237 t = ntohs(*(u16 *) p);
1238 p += 2;
1239 s = ntohs(*(u16 *) p);
1240 p += 2;
1241 if (s >= MAXSESSION)
1242 {
1243 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
1244 STAT(tunnel_rx_errors);
1245 return;
1246 }
1247 if (t >= MAXTUNNEL)
1248 {
1249 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
1250 STAT(tunnel_rx_errors);
1251 return;
1252 }
1253 if (*buf & 0x08)
1254 { // ns/nr
1255 ns = ntohs(*(u16 *) p);
1256 p += 2;
1257 nr = ntohs(*(u16 *) p);
1258 p += 2;
1259 }
1260 if (*buf & 0x02)
1261 { // offset
1262 u16 o = ntohs(*(u16 *) p);
1263 p += o + 2;
1264 }
1265 if ((p - buf) > l)
1266 {
1267 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
1268 STAT(tunnel_rx_errors);
1269 return;
1270 }
1271 l -= (p - buf);
1272 if (*buf & 0x80)
1273 { // control
1274 u16 message = 0xFFFF; // message type
1275 u8 fatal = 0;
1276 u8 mandatorymessage = 0;
1277 u8 chap = 0; // if CHAP being used
1278 u16 asession = 0; // assigned session
1279 u32 amagic = 0; // magic number
1280 u8 aflags = 0; // flags from last LCF
1281 u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1282 int requestchap = 0; // do we request PAP instead of original CHAP request?
1283 char called[MAXTEL] = ""; // called number
1284 char calling[MAXTEL] = ""; // calling number
1285
1286 if (!config->cluster_iam_master) {
1287 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1288 return;
1289 }
1290
1291 if ((*buf & 0xCA) != 0xC8)
1292 {
1293 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
1294 STAT(tunnel_rx_errors);
1295 return;
1296 }
1297 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",
1298 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1299 // if no tunnel specified, assign one
1300 if (!t)
1301 {
1302 int i;
1303
1304 //
1305 // Is this a duplicate of the first packet? (SCCRQ)
1306 //
1307 for ( i = 1; i <= config->cluster_highest_tunnelid ; ++i) {
1308 if (tunnel[i].state != TUNNELOPENING ||
1309 tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
1310 tunnel[i].port != ntohs(addr->sin_port) )
1311 continue;
1312 t = i;
1313 break;
1314 }
1315 }
1316
1317 if (!t) {
1318 if (!(t = new_tunnel()))
1319 {
1320 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
1321 STAT(tunnel_overflow);
1322 return;
1323 }
1324 tunnelclear(t);
1325 tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
1326 tunnel[t].port = ntohs(addr->sin_port);
1327 tunnel[t].window = 4; // default window
1328 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);
1329 STAT(tunnel_created);
1330 }
1331
1332 // This is used to time out old tunnels
1333 tunnel[t].lastrec = time_now;
1334
1335 // check sequence of this message
1336 {
1337 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1338 // some to clear maybe?
1339 while (tunnel[t].controlc && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1340 {
1341 controlt *c = tunnel[t].controls;
1342 tunnel[t].controls = c->next;
1343 tunnel[t].controlc--;
1344 c->next = controlfree;
1345 controlfree = c;
1346 skip--;
1347 tunnel[t].try = 0; // we have progress
1348 }
1349
1350 // If the 'ns' just received is not the 'nr' we're
1351 // expecting, just send an ack and drop it.
1352 //
1353 // if 'ns' is less, then we got a retransmitted packet.
1354 // if 'ns' is greater than missed a packet. Either way
1355 // we should ignore it.
1356 if (ns != tunnel[t].nr)
1357 {
1358 // is this the sequence we were expecting?
1359 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);
1360 STAT(tunnel_rx_errors);
1361
1362 if (l) // Is this not a ZLB?
1363 controlnull(t);
1364 return;
1365 }
1366 // receiver advance (do here so quoted correctly in any sends below)
1367 if (l) tunnel[t].nr = (ns + 1);
1368 if (skip < 0) skip = 0;
1369 if (skip < tunnel[t].controlc)
1370 {
1371 // some control packets can now be sent that were previous stuck out of window
1372 int tosend = tunnel[t].window - skip;
1373 controlt *c = tunnel[t].controls;
1374 while (c && skip)
1375 {
1376 c = c->next;
1377 skip--;
1378 }
1379 while (c && tosend)
1380 {
1381 tunnel[t].try = 0; // first send
1382 tunnelsend(c->buf, c->length, t);
1383 c = c->next;
1384 tosend--;
1385 }
1386 }
1387 if (!tunnel[t].controlc)
1388 tunnel[t].retry = 0; // caught up
1389 }
1390 if (l)
1391 { // if not a null message
1392 // process AVPs
1393 while (l && !(fatal & 0x80))
1394 {
1395 u16 n = (ntohs(*(u16 *) p) & 0x3FF);
1396 u8 *b = p;
1397 u8 flags = *p;
1398 u16 mtype;
1399 p += n; // next
1400 if (l < n)
1401 {
1402 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
1403 STAT(tunnel_rx_errors);
1404 fatal = flags;
1405 return;
1406 }
1407 l -= n;
1408 if (flags & 0x40)
1409 {
1410 // handle hidden AVPs
1411 if (!*config->l2tpsecret)
1412 {
1413 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
1414 fatal = flags;
1415 continue;
1416 }
1417 if (!session[s].random_vector_length)
1418 {
1419 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
1420 fatal = flags;
1421 continue;
1422 }
1423 log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
1424 }
1425 if (*b & 0x3C)
1426 {
1427 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
1428 fatal = flags;
1429 continue; // next
1430 }
1431 b += 2;
1432 if (*(u16 *) (b))
1433 {
1434 log(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
1435 fatal = flags;
1436 continue; // next
1437 }
1438 b += 2;
1439 mtype = ntohs(*(u16 *) (b));
1440 b += 2;
1441 n -= 6;
1442
1443 log(4, ntohl(addr->sin_addr.s_addr), s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1444 switch (mtype)
1445 {
1446 case 0: // message type
1447 message = ntohs(*(u16 *) b);
1448 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Message type = %d (%s)\n", *b,
1449 l2tp_message_types[message]);
1450 mandatorymessage = flags;
1451 break;
1452 case 1: // result code
1453 {
1454 u16 rescode = ntohs(*(u16 *)(b));
1455 const char* resdesc = "(unknown)";
1456 if (message == 4) { /* StopCCN */
1457 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1458 resdesc = stopccn_result_codes[rescode];
1459 } else if (message == 14) { /* CDN */
1460 if (rescode <= MAX_CDN_RESULT_CODE)
1461 resdesc = cdn_result_codes[rescode];
1462 }
1463
1464 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Result Code %d: %s\n",
1465 rescode, resdesc);
1466 if (n >= 4) {
1467 u16 errcode = ntohs(*(u16 *)(b + 2));
1468 const char* errdesc = "(unknown)";
1469 if (errcode <= MAX_ERROR_CODE)
1470 errdesc = error_codes[errcode];
1471 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error Code %d: %s\n",
1472 errcode, errdesc);
1473 }
1474 if (n > 4)
1475 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error String: %.*s\n",
1476 n-4, b+4);
1477
1478 break;
1479 }
1480 break;
1481 case 2: // protocol version
1482 {
1483 version = ntohs(*(u16 *) (b));
1484 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Protocol version = %d\n", version);
1485 if (version && version != 0x0100)
1486 { // allow 0.0 and 1.0
1487 log(1, ntohl(addr->sin_addr.s_addr), s, t, " Bad protocol version %04X\n",
1488 version);
1489 fatal = flags;
1490 continue; // next
1491 }
1492 }
1493 break;
1494 case 3: // framing capabilities
1495 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
1496 break;
1497 case 4: // bearer capabilities
1498 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
1499 break;
1500 case 5: // tie breaker
1501 // We never open tunnels, so we don't care about tie breakers
1502 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
1503 continue;
1504 case 6: // firmware revision
1505 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
1506 break;
1507 case 7: // host name
1508 memset(tunnel[t].hostname, 0, 128);
1509 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1510 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1511 // TBA - to send to RADIUS
1512 break;
1513 case 8: // vendor name
1514 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1515 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1516 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1517 break;
1518 case 9: // assigned tunnel
1519 tunnel[t].far = ntohs(*(u16 *) (b));
1520 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1521 break;
1522 case 10: // rx window
1523 tunnel[t].window = ntohs(*(u16 *) (b));
1524 if (!tunnel[t].window)
1525 tunnel[t].window = 1; // window of 0 is silly
1526 log(4, ntohl(addr->sin_addr.s_addr), s, t, " rx window = %d\n", tunnel[t].window);
1527 break;
1528 case 11: // Challenge
1529 {
1530 log(4, ntohl(addr->sin_addr.s_addr), s, t, " LAC requested CHAP authentication for tunnel\n");
1531 build_chap_response(b, 2, n, &chapresponse);
1532 }
1533 break;
1534 case 14: // assigned session
1535 asession = session[s].far = ntohs(*(u16 *) (b));
1536 log(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
1537 break;
1538 case 15: // call serial number
1539 log(4, ntohl(addr->sin_addr.s_addr), s, t, " call serial number = %d\n", ntohl(*(u32 *)b));
1540 break;
1541 case 18: // bearer type
1542 log(4, ntohl(addr->sin_addr.s_addr), s, t, " bearer type = %d\n", ntohl(*(u32 *)b));
1543 // TBA - for RADIUS
1544 break;
1545 case 19: // framing type
1546 log(4, ntohl(addr->sin_addr.s_addr), s, t, " framing type = %d\n", ntohl(*(u32 *)b));
1547 // TBA
1548 break;
1549 case 21: // called number
1550 memset(called, 0, MAXTEL);
1551 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1552 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Called <%s>\n", called);
1553 break;
1554 case 22: // calling number
1555 memset(calling, 0, MAXTEL);
1556 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1557 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Calling <%s>\n", calling);
1558 break;
1559 case 24: // tx connect speed
1560 if (n == 4)
1561 {
1562 session[s].tx_connect_speed = ntohl(*(u32 *)b);
1563 }
1564 else
1565 {
1566 // AS5300s send connect speed as a string
1567 char tmp[30] = {0};
1568 memcpy(tmp, b, (n >= 30) ? 30 : n);
1569 session[s].tx_connect_speed = atol(tmp);
1570 }
1571 log(4, ntohl(addr->sin_addr.s_addr), s, t, " TX connect speed <%u>\n",
1572 session[s].tx_connect_speed);
1573 break;
1574 case 38: // rx connect speed
1575 if (n == 4)
1576 {
1577 session[s].rx_connect_speed = ntohl(*(u32 *)b);
1578 }
1579 else
1580 {
1581 // AS5300s send connect speed as a string
1582 char tmp[30] = {0};
1583 memcpy(tmp, b, (n >= 30) ? 30 : n);
1584 session[s].rx_connect_speed = atol(tmp);
1585 }
1586 log(4, ntohl(addr->sin_addr.s_addr), s, t, " RX connect speed <%u>\n",
1587 session[s].rx_connect_speed);
1588 break;
1589 case 25: // Physical Channel ID
1590 {
1591 u32 tmp = ntohl(*(u32 *)b);
1592 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Physical Channel ID <%X>\n", tmp);
1593 break;
1594 }
1595 case 29: // Proxy Authentication Type
1596 {
1597 u16 authtype = ntohs(*(u16 *)b);
1598 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Type %d (%s)\n",
1599 authtype, authtypes[authtype]);
1600 requestchap = (authtype == 2);
1601 break;
1602 }
1603 case 30: // Proxy Authentication Name
1604 {
1605 char authname[64] = {0};
1606 memcpy(authname, b, (n > 63) ? 63 : n);
1607 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Name (%s)\n",
1608 authname);
1609 break;
1610 }
1611 case 31: // Proxy Authentication Challenge
1612 {
1613 memcpy(radius[session[s].radius].auth, b, 16);
1614 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Challenge\n");
1615 break;
1616 }
1617 case 32: // Proxy Authentication ID
1618 {
1619 u16 authid = ntohs(*(u16 *)(b));
1620 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth ID (%d)\n",
1621 authid);
1622 if (session[s].radius)
1623 radius[session[s].radius].id = authid;
1624 break;
1625 }
1626 case 33: // Proxy Authentication Response
1627 {
1628 char authresp[64] = {0};
1629 memcpy(authresp, b, (n > 63) ? 63 : n);
1630 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Response\n");
1631 break;
1632 }
1633 case 27: // last send lcp
1634 { // find magic number
1635 u8 *p = b, *e = p + n;
1636 while (p < e && p[1])
1637 {
1638 if (*p == 5 && p[1] == 6)
1639 amagic = ntohl(*(u32 *) (p + 2));
1640 else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5)
1641 chap = 1;
1642 else if (*p == 7)
1643 aflags |= SESSIONPFC;
1644 else if (*p == 8)
1645 aflags |= SESSIONACFC;
1646 p += p[1];
1647 }
1648
1649 {
1650 char tmp[500] = {0};
1651 tmp[0] = ConfigReq;
1652 memcpy((tmp + 1), b, n);
1653 }
1654 }
1655 break;
1656 case 28: // last recv lcp confreq
1657 {
1658 char tmp[500] = {0};
1659 tmp[0] = ConfigReq;
1660 memcpy((tmp + 1), b, n);
1661 break;
1662 }
1663 case 26: // Initial Received LCP CONFREQ
1664 {
1665 char tmp[500] = {0};
1666 tmp[0] = ConfigReq;
1667 memcpy((tmp + 1), b, n);
1668 }
1669 break;
1670 case 39: // seq required - we control it as an LNS anyway...
1671 break;
1672 case 36: // Random Vector
1673 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Random Vector received. Enabled AVP Hiding.\n");
1674 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1675 memcpy(session[s].random_vector, b, n);
1676 session[s].random_vector_length = n;
1677 break;
1678 default:
1679 log(2, ntohl(addr->sin_addr.s_addr), s, t, " Unknown AVP type %d\n", mtype);
1680 fatal = flags;
1681 continue; // next
1682 }
1683 }
1684 // process message
1685 if (fatal & 0x80)
1686 tunnelshutdown(t, "Unknown Mandatory AVP");
1687 else
1688 switch (message)
1689 {
1690 case 1: // SCCRQ - Start Control Connection Request
1691 {
1692 controlt *c = controlnew(2); // sending SCCRP
1693 control16(c, 2, version, 1); // protocol version
1694 control32(c, 3, 3, 1); // framing
1695 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1696 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1697 control16(c, 9, t, 1); // assigned tunnel
1698 controladd(c, t, s); // send the resply
1699 }
1700 tunnel[t].state = TUNNELOPENING;
1701 break;
1702 case 2: // SCCRP
1703 tunnel[t].state = TUNNELOPEN;
1704 break;
1705 case 3: // SCCN
1706 tunnel[t].state = TUNNELOPEN;
1707 controlnull(t); // ack
1708 break;
1709 case 4: // StopCCN
1710 controlnull(t); // ack
1711 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1712 tunnelkill(t, "Stopped"); // Immediately force everything dead
1713 break;
1714 case 6: // HELLO
1715 controlnull(t); // simply ACK
1716 break;
1717 case 7: // OCRQ
1718 // TBA
1719 break;
1720 case 8: // OCRO
1721 // TBA
1722 break;
1723 case 9: // OCCN
1724 // TBA
1725 break;
1726 case 10: // ICRQ
1727 if (!sessionfree)
1728 {
1729 STAT(session_overflow);
1730 tunnelshutdown(t, "No free sessions");
1731 }
1732 else
1733 {
1734 u16 r;
1735 controlt *c;
1736
1737 s = sessionfree;
1738 sessionfree = session[s].next;
1739 memset(&session[s], 0, sizeof(session[s]));
1740
1741 if (s > config->cluster_highest_sessionid)
1742 config->cluster_highest_sessionid = s;
1743
1744 // make a RADIUS session
1745 if (!(r = radiusnew(s)))
1746 {
1747 log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
1748 sessionkill(s, "no free RADIUS sesions");
1749 return;
1750 }
1751
1752 c = controlnew(11); // sending ICRP
1753 session[s].id = sessionid++;
1754 session[s].opened = time(NULL);
1755 session[s].tunnel = t;
1756 session[s].far = asession;
1757 session[s].last_packet = time_now;
1758 log(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1759 control16(c, 14, s, 1); // assigned session
1760 controladd(c, t, s); // send the reply
1761 {
1762 // Generate a random challenge
1763 int n;
1764 for (n = 0; n < 15; n++)
1765 radius[r].auth[n] = rand();
1766 }
1767 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1768 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1769 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1770 STAT(session_created);
1771 }
1772 break;
1773 case 11: // ICRP
1774 // TBA
1775 break;
1776 case 12: // ICCN
1777 session[s].magic = amagic; // set magic number
1778 session[s].l2tp_flags = aflags; // set flags received
1779 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
1780 controlnull(t); // ack
1781 // In CHAP state, request PAP instead
1782 if (requestchap)
1783 initlcp(t, s);
1784 break;
1785 case 14: // CDN
1786 controlnull(t); // ack
1787 sessionshutdown(s, "Closed (Received CDN)");
1788 break;
1789 case 0xFFFF:
1790 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
1791 break;
1792 default:
1793 STAT(tunnel_rx_errors);
1794 if (mandatorymessage & 0x80)
1795 tunnelshutdown(t, "Unknown message");
1796 else
1797 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
1798 break;
1799 }
1800 if (chapresponse) free(chapresponse);
1801 cluster_send_tunnel(t);
1802 }
1803 else
1804 {
1805 log(4, 0, s, t, " Got a ZLB ack\n");
1806 }
1807 }
1808 else
1809 { // data
1810 u16 prot;
1811
1812 log_hex(5, "Receive Tunnel Data", p, l);
1813 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1814 { // HDLC address header, discard
1815 p += 2;
1816 l -= 2;
1817 }
1818 if (l < 2)
1819 {
1820 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
1821 STAT(tunnel_rx_errors);
1822 return;
1823 }
1824 if (*p & 1)
1825 {
1826 prot = *p++;
1827 l--;
1828 }
1829 else
1830 {
1831 prot = ntohs(*(u16 *) p);
1832 p += 2;
1833 l -= 2;
1834 }
1835
1836 if (s && !session[s].tunnel) // Is something wrong??
1837 {
1838 if (!config->cluster_iam_master)
1839 {
1840 // Pass it off to the master to deal with..
1841 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1842 return;
1843 }
1844
1845
1846 log(1, ntohl(addr->sin_addr.s_addr), s, t, "UDP packet contains session %d "
1847 "but no session[%d].tunnel exists (LAC said"
1848 " tunnel = %d). Dropping packet.\n", s, s, t);
1849 STAT(tunnel_rx_errors);
1850 return;
1851 }
1852
1853 if (session[s].die)
1854 {
1855 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
1856 // I'm pretty sure this isn't right -- mo.
1857 // return; // closing session, PPP not processed
1858 }
1859 if (prot == PPPPAP)
1860 {
1861 session[s].last_packet = time_now;
1862 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1863 processpap(t, s, p, l);
1864 }
1865 else if (prot == PPPCHAP)
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 processchap(t, s, p, l);
1870 }
1871 else if (prot == PPPLCP)
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 processlcp(t, s, p, l);
1876 }
1877 else if (prot == PPPIPCP)
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 processipcp(t, s, p, l);
1882 }
1883 else if (prot == PPPCCP)
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 processccp(t, s, p, l);
1888 }
1889 else if (prot == PPPIP)
1890 {
1891 if (!config->cluster_iam_master)
1892 {
1893 // We're a slave. Should we forward this packet to the master?
1894
1895 // Is this a walled garden session, or something that needs it's
1896 // idle time updated??
1897
1898 // Maintain the idle timeouts on the master. If this would
1899 // significantly reset the idletimeout, run it via the master
1900 // to refresh the master's idle timer.
1901 // Not sure this is ideal: It may re-order packets.
1902
1903 if (session[s].walled_garden || (session[s].last_packet + (ECHO_TIMEOUT/2)) < time_now)
1904 {
1905 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1906 session[s].last_packet = time_now;
1907 return;
1908 }
1909 // fall through to processipin.
1910 } else
1911 session[s].last_packet = time_now;
1912 processipin(t, s, p, l);
1913 }
1914 else
1915 {
1916 STAT(tunnel_rx_errors);
1917 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
1918 }
1919 }
1920 }
1921
1922 // read and process packet on tun
1923 void processtun(u8 * buf, int len)
1924 {
1925 log_hex(5, "Receive TUN Data", buf, len);
1926 STAT(tun_rx_packets);
1927 INC_STAT(tun_rx_bytes, len);
1928
1929 CSTAT(call_processtun);
1930
1931 eth_rx_pkt++;
1932 eth_rx += len;
1933 if (len < 22)
1934 {
1935 log(1, 0, 0, 0, "Short tun packet %d bytes\n", len);
1936 STAT(tun_rx_errors);
1937 return;
1938 }
1939
1940 if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
1941 processipout(buf, len);
1942 // Else discard.
1943 }
1944
1945 //
1946 // Maximum number of actions to complete.
1947 // This is to avoid sending out too many packets
1948 // at once.
1949 #define MAX_ACTIONS 500
1950
1951 int regular_cleanups(void)
1952 {
1953 static sessionidt s = 0; // Next session to check for actions on.
1954 tunnelidt t;
1955 int count=0,i;
1956 u16 r;
1957 static clockt next_acct = 0;
1958 int a;
1959
1960 log(3, 0, 0, 0, "Begin regular cleanup\n");
1961
1962 for (r = 1; r < MAXRADIUS; r++)
1963 {
1964 if (!radius[r].state)
1965 continue;
1966 if (radius[r].retry)
1967 {
1968 if (radius[r].retry <= TIME)
1969 radiusretry(r);
1970 } else
1971 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
1972 }
1973 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
1974 {
1975 // check for expired tunnels
1976 if (tunnel[t].die && tunnel[t].die <= TIME)
1977 {
1978 STAT(tunnel_timeout);
1979 tunnelkill(t, "Expired");
1980 continue;
1981 }
1982 // check for message resend
1983 if (tunnel[t].retry && tunnel[t].controlc)
1984 {
1985 // resend pending messages as timeout on reply
1986 if (tunnel[t].retry <= TIME)
1987 {
1988 controlt *c = tunnel[t].controls;
1989 u8 w = tunnel[t].window;
1990 tunnel[t].try++; // another try
1991 if (tunnel[t].try > 5)
1992 tunnelkill(t, "Timeout on control message"); // game over
1993 else
1994 while (c && w--)
1995 {
1996 tunnelsend(c->buf, c->length, t);
1997 c = c->next;
1998 }
1999 }
2000 }
2001 // Send hello
2002 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2003 {
2004 controlt *c = controlnew(6); // sending HELLO
2005 controladd(c, t, 0); // send the message
2006 log(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
2007 }
2008
2009 // Check for tunnel changes requested from the CLI
2010 if ((a = cli_tunnel_actions[t].action))
2011 {
2012 cli_tunnel_actions[t].action = 0;
2013 if (a & CLI_TUN_KILL)
2014 {
2015 log(2, tunnel[t].ip, 0, t, "Dropping tunnel by CLI\n");
2016 tunnelshutdown(t, "Requested by administrator");
2017 }
2018 }
2019
2020 }
2021
2022 count = 0;
2023 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2024 {
2025 s++;
2026 if (s > config->cluster_highest_sessionid)
2027 s = 1;
2028
2029 if (!session[s].tunnel) // Session isn't in use
2030 continue;
2031
2032 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED) )
2033 {
2034 // IPCP has not completed yet. Resend
2035 log(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2036 sendipcp(session[s].tunnel, s);
2037 }
2038
2039 // check for expired sessions
2040 if (session[s].die && session[s].die <= TIME)
2041 {
2042 sessionkill(s, "Expired");
2043 if (++count >= MAX_ACTIONS) break;
2044 continue;
2045 }
2046
2047 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2048 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2049 {
2050 sessionkill(s, "No response to LCP ECHO requests");
2051 STAT(session_timeout);
2052 if (++count >= MAX_ACTIONS) break;
2053 continue;
2054 }
2055
2056 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2057 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2058 {
2059 u8 b[MAXCONTROL] = {0};
2060
2061 u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2062 if (!q) {
2063 log(3, session[s].ip, s, t, "failed to send ECHO packet.\n");
2064 continue;
2065 }
2066
2067 *q = EchoReq;
2068 *(u8 *)(q + 1) = (time_now % 255); // ID
2069 *(u16 *)(q + 2) = htons(8); // Length
2070 *(u32 *)(q + 4) = 0; // Magic Number (not supported)
2071
2072 log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2073 (int)(time_now - session[s].last_packet));
2074 tunnelsend(b, 24, session[s].tunnel); // send it
2075 if (++count >= MAX_ACTIONS) break;
2076 continue;
2077 }
2078
2079 // Check for actions requested from the CLI
2080 if ((a = cli_session_actions[s].action))
2081 {
2082 int send = 0;
2083
2084 cli_session_actions[s].action = 0;
2085 if (a & CLI_SESS_KILL)
2086 {
2087 log(2, 0, s, session[s].tunnel, "Dropping session by CLI\n");
2088 sessionshutdown(s, "Requested by administrator");
2089 a = 0; // dead, no need to check for other actions
2090 }
2091
2092 if (a & CLI_SESS_SNOOP)
2093 {
2094 log(2, 0, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2095 inet_toa(cli_session_actions[s].snoop_ip), cli_session_actions[s].snoop_port);
2096
2097 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2098 session[s].snoop_port = cli_session_actions[s].snoop_port;
2099 send++;
2100 }
2101
2102 if (a & CLI_SESS_NOSNOOP)
2103 {
2104 log(2, 0, s, session[s].tunnel, "Unsnooping session by CLI\n");
2105 session[s].snoop_ip = 0;
2106 session[s].snoop_port = 0;
2107 send++;
2108 }
2109
2110 if (a & CLI_SESS_THROTTLE)
2111 {
2112 log(2, 0, s, session[s].tunnel, "Throttling session by CLI (to %d)\n",
2113 cli_session_actions[s].throttle);
2114
2115 throttle_session(s, cli_session_actions[s].throttle);
2116 }
2117
2118 if (a & CLI_SESS_NOTHROTTLE)
2119 {
2120 log(2, 0, s, session[s].tunnel, "Un-throttling session by CLI\n");
2121 throttle_session(s, 0);
2122 }
2123
2124 if (send)
2125 cluster_send_session(s);
2126
2127 if (++count >= MAX_ACTIONS) break;
2128 continue;
2129 }
2130 }
2131
2132 if (config->accounting_dir && next_acct <= TIME)
2133 {
2134 // Dump accounting data
2135 next_acct = TIME + ACCT_TIME;
2136 dump_acct_info();
2137 }
2138
2139 if (count >= MAX_ACTIONS)
2140 return 1; // Didn't finish!
2141
2142 log(3, 0, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2143 return 0;
2144 }
2145
2146
2147 //
2148 // Are we in the middle of a tunnel update, or radius
2149 // requests??
2150 //
2151 int still_busy(void)
2152 {
2153 int i;
2154 static int last_talked = 0;
2155 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i) {
2156 if (!tunnel[i].controlc)
2157 continue;
2158
2159 if (last_talked != TIME) {
2160 log(2,0,0,0, "Tunnel %d still has un-acked control messages.\n", i);
2161 last_talked = TIME;
2162 }
2163 return 1;
2164 }
2165
2166 for (i = 1; i < MAXRADIUS; i++)
2167 {
2168 if (radius[i].state == RADIUSNULL)
2169 continue;
2170 if (radius[i].state == RADIUSWAIT)
2171 continue;
2172
2173 if (last_talked != TIME) {
2174 log(2,0,0,0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2175 last_talked = TIME;
2176 }
2177 return 1;
2178 }
2179
2180 return 0;
2181 }
2182
2183 // main loop - gets packets on tun or udp and processes them
2184 void mainloop(void)
2185 {
2186 fd_set cr;
2187 int cn, i;
2188 u8 buf[65536];
2189 struct timeval to;
2190 clockt next_cluster_ping = 0; // send initial ping immediately
2191 time_t next_clean = time_now + config->cleanup_interval;
2192
2193 log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2194 udpfd, tunfd, cluster_sockfd, controlfd);
2195
2196 FD_ZERO(&cr);
2197 FD_SET(udpfd, &cr);
2198 FD_SET(tunfd, &cr);
2199 FD_SET(controlfd, &cr);
2200 FD_SET(clifd, &cr);
2201 if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
2202 cn = udpfd;
2203 if (cn < tunfd) cn = tunfd;
2204 if (cn < controlfd) cn = controlfd;
2205 if (cn < clifd) cn = clifd;
2206 if (cn < cluster_sockfd) cn = cluster_sockfd;
2207 for (i = 0; i < config->num_radfds; i++)
2208 {
2209 if (!radfds[i]) continue;
2210 FD_SET(radfds[i], &cr);
2211 if (radfds[i] > cn)
2212 cn = radfds[i];
2213 }
2214
2215 while (!main_quit || still_busy())
2216 {
2217 fd_set r;
2218 int n = cn;
2219 #ifdef BGP
2220 fd_set w;
2221 int bgp_set[BGP_NUM_PEERS];
2222 #endif /* BGP */
2223
2224 if (config->reload_config)
2225 {
2226 // Update the config state based on config settings
2227 update_config();
2228 }
2229
2230 memcpy(&r, &cr, sizeof(fd_set));
2231 to.tv_sec = 0;
2232 to.tv_usec = 100000; // 1/10th of a second.
2233
2234 #ifdef BGP
2235 FD_ZERO(&w);
2236 for (i = 0; i < BGP_NUM_PEERS; i++)
2237 {
2238 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2239 if (bgp_set[i] & 1)
2240 {
2241 FD_SET(bgp_peers[i].sock, &r);
2242 if (bgp_peers[i].sock > n)
2243 n = bgp_peers[i].sock;
2244 }
2245
2246 if (bgp_set[i] & 2)
2247 {
2248 FD_SET(bgp_peers[i].sock, &w);
2249 if (bgp_peers[i].sock > n)
2250 n = bgp_peers[i].sock;
2251 }
2252 }
2253
2254 n = select(n + 1, &r, &w, 0, &to);
2255 #else /* BGP */
2256 n = select(n + 1, &r, 0, 0, &to);
2257 #endif /* BGP */
2258
2259 TIME = now();
2260 if (n < 0)
2261 {
2262 if (errno == EINTR)
2263 continue;
2264
2265 log(0, 0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2266 main_quit++;
2267 break;
2268 }
2269 else if (n)
2270 {
2271 struct sockaddr_in addr;
2272 int alen = sizeof(addr);
2273 if (FD_ISSET(udpfd, &r))
2274 {
2275 int c, n;
2276 for (c = 0; c < config->multi_read_count; c++)
2277 {
2278 if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2279 processudp(buf, n, &addr);
2280 else
2281 break;
2282 }
2283 }
2284 if (FD_ISSET(tunfd, &r))
2285 {
2286 int c, n;
2287 for (c = 0; c < config->multi_read_count; c++)
2288 {
2289 if ((n = read(tunfd, buf, sizeof(buf))) > 0)
2290 processtun(buf, n);
2291 else
2292 break;
2293 }
2294 }
2295 for (i = 0; i < config->num_radfds; i++)
2296 if (FD_ISSET(radfds[i], &r))
2297 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2298 if (FD_ISSET(cluster_sockfd, &r)) {
2299 int size;
2300 size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
2301 processcluster(buf, size, addr.sin_addr.s_addr);
2302 }
2303 if (FD_ISSET(controlfd, &r))
2304 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
2305 if (FD_ISSET(clifd, &r))
2306 {
2307 struct sockaddr_in addr;
2308 int sockfd;
2309 int len = sizeof(addr);
2310
2311 if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
2312 {
2313 log(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
2314 continue;
2315 }
2316 else
2317 {
2318 cli_do(sockfd);
2319 close(sockfd);
2320 }
2321 }
2322 }
2323
2324 // Runs on every machine (master and slaves).
2325 if (cluster_sockfd && next_cluster_ping <= TIME)
2326 {
2327 // Check to see which of the cluster is still alive..
2328
2329 cluster_send_ping(basetime); // Only does anything if we're a slave
2330 cluster_check_master(); // ditto.
2331
2332 cluster_heartbeat(); // Only does anything if we're a master.
2333 cluster_check_slaves(); // ditto.
2334
2335 master_update_counts(); // If we're a slave, send our byte counters to our master.
2336
2337 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2338 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2339 else
2340 next_cluster_ping = TIME + config->cluster_hb_interval;
2341 }
2342
2343 // Run token bucket filtering queue..
2344 // Only run it every 1/10th of a second.
2345 // Runs on all machines both master and slave.
2346 {
2347 static clockt last_run = 0;
2348 if (last_run != TIME) {
2349 last_run = TIME;
2350 tbf_run_timer();
2351 }
2352 }
2353
2354 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2355 * something to read, else under load this will never actually run....
2356 *
2357 */
2358 if (config->cluster_iam_master && next_clean <= time_now) {
2359 if (regular_cleanups()) { // Did it finish?
2360 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2361 } else {
2362 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2363 }
2364 }
2365
2366 #ifdef BGP
2367 for (i = 0; i < BGP_NUM_PEERS; i++)
2368 {
2369 bgp_process(&bgp_peers[i],
2370 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
2371 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
2372 }
2373 #endif /* BGP */
2374 }
2375
2376 // Are we the master and shutting down??
2377 if (config->cluster_iam_master)
2378 cluster_heartbeat(); // Flush any queued changes..
2379
2380 // Ok. Notify everyone we're shutting down. If we're
2381 // the master, this will force an election.
2382 cluster_send_ping(0);
2383
2384 //
2385 // Important!!! We MUST not process any packets past this point!
2386 }
2387
2388 // Init data structures
2389 void initdata(void)
2390 {
2391 int i;
2392
2393 _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2394 if (_statistics == MAP_FAILED)
2395 {
2396 log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
2397 exit(1);
2398 }
2399 config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2400 if (config == MAP_FAILED)
2401 {
2402 log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
2403 exit(1);
2404 }
2405 memset(config, 0, sizeof(struct configt));
2406 time(&config->start_time);
2407 strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
2408 tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2409 if (tunnel == MAP_FAILED)
2410 {
2411 log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
2412 exit(1);
2413 }
2414 session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2415 if (session == MAP_FAILED)
2416 {
2417 log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
2418 exit(1);
2419 }
2420
2421 sess_count = mmap(NULL, sizeof(sessioncountt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2422 if (sess_count == MAP_FAILED)
2423 {
2424 log(0, 0, 0, 0, "Error doing mmap for sessions_count: %s\n", strerror(errno));
2425 exit(1);
2426 }
2427
2428 radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2429 if (radius == MAP_FAILED)
2430 {
2431 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2432 exit(1);
2433 }
2434 ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2435 if (ip_address_pool == MAP_FAILED)
2436 {
2437 log(0, 0, 0, 0, "Error doing mmap for ip_address_pool: %s\n", strerror(errno));
2438 exit(1);
2439 }
2440 #ifdef RINGBUFFER
2441 ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2442 if (ringbuffer == MAP_FAILED)
2443 {
2444 log(0, 0, 0, 0, "Error doing mmap for ringbuffer: %s\n", strerror(errno));
2445 exit(1);
2446 }
2447 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2448 #endif
2449
2450 cli_session_actions = mmap(NULL, sizeof(struct cli_session_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2451 if (cli_session_actions == MAP_FAILED)
2452 {
2453 log(0, 0, 0, 0, "Error doing mmap for cli session actions: %s\n", strerror(errno));
2454 exit(1);
2455 }
2456 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2457 cli_tunnel_actions = mmap(NULL, sizeof(struct cli_tunnel_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2458 if (cli_tunnel_actions == MAP_FAILED)
2459 {
2460 log(0, 0, 0, 0, "Error doing mmap for cli tunnel actions: %s\n", strerror(errno));
2461 exit(1);
2462 }
2463 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2464
2465 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2466 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2467 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2468 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2469
2470 // Put all the sessions on the free list marked as undefined.
2471 for (i = 1; i < MAXSESSION - 1; i++) {
2472 session[i].next = i + 1;
2473 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2474 }
2475 session[MAXSESSION - 1].next = 0;
2476 sessionfree = 1;
2477
2478 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2479 for (i = 1; i < MAXTUNNEL- 1; i++) {
2480 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2481 }
2482
2483 if (!*hostname)
2484 {
2485 char *p;
2486 // Grab my hostname unless it's been specified
2487 gethostname(hostname, sizeof(hostname));
2488 if ((p = strchr(hostname, '.'))) *p = 0;
2489 }
2490 _statistics->start_time = _statistics->last_reset = time(NULL);
2491
2492 #ifdef BGP
2493 bgp_peers = mmap(NULL, sizeof(struct bgp_peer) * BGP_NUM_PEERS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2494 if (bgp_peers == MAP_FAILED)
2495 {
2496 log(0, 0, 0, 0, "Error doing mmap for bgp: %s\n", strerror(errno));
2497 exit(1);
2498 }
2499 #endif /* BGP */
2500 }
2501
2502 void initiptables(void)
2503 {
2504 /* Flush the tables here so that we have a clean slate */
2505
2506 // Not needed. 'nat' is setup by garden.c
2507 // mangle isn't used (as throttling is done by tbf inhouse).
2508 }
2509
2510 int assign_ip_address(sessionidt s)
2511 {
2512 u32 i;
2513 int best = -1;
2514 time_t best_time = time_now;
2515 char *u = session[s].user;
2516 char reuse = 0;
2517
2518
2519 CSTAT(call_assign_ip_address);
2520
2521 for (i = 1; i < ip_pool_size; i++)
2522 {
2523 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2524 continue;
2525
2526 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2527 {
2528 best = i;
2529 reuse = 1;
2530 break;
2531 }
2532
2533 if (ip_address_pool[i].last < best_time)
2534 {
2535 best = i;
2536 if (!(best_time = ip_address_pool[i].last))
2537 break; // never used, grab this one
2538 }
2539 }
2540
2541 if (best < 0)
2542 {
2543 log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2544 return 0;
2545 }
2546
2547 session[s].ip = ip_address_pool[best].address;
2548 session[s].ip_pool_index = best;
2549 ip_address_pool[best].assigned = 1;
2550 ip_address_pool[best].last = time_now;
2551 ip_address_pool[best].session = s;
2552 if (session[s].walled_garden)
2553 /* Don't track addresses of users in walled garden (note: this
2554 means that their address isn't "sticky" even if they get
2555 un-gardened). */
2556 ip_address_pool[best].user[0] = 0;
2557 else
2558 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2559
2560 STAT(ip_allocated);
2561 log(4, ip_address_pool[best].address, s, session[s].tunnel,
2562 "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
2563
2564 return 1;
2565 }
2566
2567 void free_ip_address(sessionidt s)
2568 {
2569 int i = session[s].ip_pool_index;
2570
2571 if (!session[s].ip)
2572 return; // what the?
2573
2574 if (i < 0) // Is this actually part of the ip pool?
2575 i = 0;
2576
2577 STAT(ip_freed);
2578 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2579 session[s].ip = 0;
2580 ip_address_pool[i].assigned = 0;
2581 ip_address_pool[i].session = 0;
2582 ip_address_pool[i].last = time_now;
2583
2584
2585 CSTAT(call_free_ip_address);
2586
2587 }
2588
2589 //
2590 // Fsck the address pool against the session table.
2591 // Normally only called when we become a master.
2592 //
2593 // This isn't perfect: We aren't keep tracking of which
2594 // users used to have an IP address.
2595 //
2596 void rebuild_address_pool(void)
2597 {
2598 int i;
2599
2600 //
2601 // Zero the IP pool allocation, and build
2602 // a map from IP address to pool index.
2603 for (i = 1; i < MAXIPPOOL; ++i) {
2604 ip_address_pool[i].assigned = 0;
2605 ip_address_pool[i].session = 0;
2606 if (!ip_address_pool[i].address)
2607 continue;
2608
2609 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2610 }
2611
2612 for (i = 0; i < MAXSESSION; ++i) {
2613 int ipid;
2614 if (!session[i].ip || !session[i].tunnel)
2615 continue;
2616 ipid = - lookup_ipmap(htonl(session[i].ip));
2617
2618 if (session[i].ip_pool_index < 0) { // Not allocated out of the pool.
2619 if (ipid < 1) // Not found in the pool either? good.
2620 continue;
2621
2622 log(0, 0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2623 i, inet_toa(session[i].ip), ipid);
2624
2625 // Fall through and process it as part of the pool.
2626 }
2627
2628
2629 if (ipid > MAXIPPOOL || ipid < 0) {
2630 log(0, 0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2631 ipid = -1;
2632 session[i].ip_pool_index = ipid;
2633 continue;
2634 }
2635
2636 ip_address_pool[ipid].assigned = 1;
2637 ip_address_pool[ipid].session = i;
2638 ip_address_pool[ipid].last = time_now;
2639 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2640 session[i].ip_pool_index = ipid;
2641 cache_ipmap(session[i].ip, i); // Fix the ip map.
2642 }
2643 }
2644
2645 //
2646 // Fix the address pool to match a changed session.
2647 // (usually when the master sends us an update).
2648 void fix_address_pool(int sid)
2649 {
2650 int ipid;
2651
2652 ipid = session[sid].ip_pool_index;
2653
2654 if (ipid > ip_pool_size)
2655 return; // Ignore it. rebuild_address_pool will fix it up.
2656
2657 if (ip_address_pool[ipid].address != session[sid].ip)
2658 return; // Just ignore it. rebuild_address_pool will take care of it.
2659
2660 ip_address_pool[ipid].assigned = 1;
2661 ip_address_pool[ipid].session = sid;
2662 ip_address_pool[ipid].last = time_now;
2663 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2664 }
2665
2666 //
2667 // Add a block of addresses to the IP pool to hand out.
2668 //
2669 void add_to_ip_pool(u32 addr, u32 mask)
2670 {
2671 int i;
2672 if (mask == 0)
2673 mask = 0xffffffff; // Host route only.
2674
2675 addr &= mask;
2676
2677 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2678 return ;
2679
2680 for (i = addr ;(i & mask) == addr; ++i)
2681 {
2682 if ((i & 0xff) == 0 || (i&0xff) == 255)
2683 continue; // Skip 0 and broadcast addresses.
2684
2685 ip_address_pool[ip_pool_size].address = i;
2686 ip_address_pool[ip_pool_size].assigned = 0;
2687 ++ip_pool_size;
2688 if (ip_pool_size >= MAXIPPOOL)
2689 {
2690 log(0,0,0,0, "Overflowed IP pool adding %s\n", inet_toa(htonl(addr)) );
2691 return;
2692 }
2693 }
2694 }
2695
2696 // Initialize the IP address pool
2697 void initippool()
2698 {
2699 FILE *f;
2700 char *p;
2701 char buf[4096];
2702 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2703
2704 if (!(f = fopen(IPPOOLFILE, "r")))
2705 {
2706 log(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2707 exit(1);
2708 }
2709
2710 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2711 {
2712 char *pool = buf;
2713 buf[4095] = 0; // Force it to be zero terminated/
2714
2715 if (*buf == '#' || *buf == '\n')
2716 continue; // Skip comments / blank lines
2717 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2718 if ((p = (char *)strchr(buf, ':')))
2719 {
2720 ipt src;
2721 *p = '\0';
2722 src = inet_addr(buf);
2723 if (src == INADDR_NONE)
2724 {
2725 log(0, 0, 0, 0, "Invalid address pool IP %s\n", buf);
2726 exit(1);
2727 }
2728 // This entry is for a specific IP only
2729 if (src != config->bind_address)
2730 continue;
2731 *p = ':';
2732 pool = p+1;
2733 }
2734 if ((p = (char *)strchr(pool, '/')))
2735 {
2736 // It's a range
2737 int numbits = 0;
2738 u32 start = 0, mask = 0;
2739
2740 log(2, 0, 0, 0, "Adding IP address range %s\n", buf);
2741 *p++ = 0;
2742 if (!*p || !(numbits = atoi(p)))
2743 {
2744 log(0, 0, 0, 0, "Invalid pool range %s\n", buf);
2745 continue;
2746 }
2747 start = ntohl(inet_addr(pool));
2748 mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
2749
2750 // Add a static route for this pool
2751 log(5, 0, 0, 0, "Adding route for address pool %s/%u\n", inet_toa(htonl(start)), 32 + mask);
2752 routeset(0, start, mask, 0, 1);
2753
2754 add_to_ip_pool(start, mask);
2755 }
2756 else
2757 {
2758 // It's a single ip address
2759 add_to_ip_pool(inet_addr(pool), 0);
2760 }
2761 }
2762 fclose(f);
2763 log(1, 0, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2764 }
2765
2766 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
2767 {
2768 struct sockaddr_in snoop_addr = {0};
2769 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2770 return;
2771
2772 snoop_addr.sin_family = AF_INET;
2773 snoop_addr.sin_addr.s_addr = destination;
2774 snoop_addr.sin_port = ntohs(port);
2775
2776 log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
2777 packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
2778 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
2779 log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
2780 STAT(packets_snooped);
2781 }
2782
2783 void dump_acct_info()
2784 {
2785 char filename[1024];
2786 char timestr[64];
2787 time_t t = time(NULL);
2788 int i;
2789 FILE *f = NULL;
2790
2791
2792 CSTAT(call_dump_acct_info);
2793
2794 strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
2795 snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
2796
2797 for (i = 0; i < MAXSESSION; i++)
2798 {
2799 if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
2800 continue;
2801 if (!f)
2802 {
2803 time_t now = time(NULL);
2804 if (!(f = fopen(filename, "w")))
2805 {
2806 log(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
2807 return;
2808 }
2809 log(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
2810 fprintf(f, "# dslwatch.pl dump file V1.01\n"
2811 "# host: %s\n"
2812 "# time: %ld\n"
2813 "# uptime: %ld\n"
2814 "# format: username ip qos uptxoctets downrxoctets\n",
2815 hostname,
2816 now,
2817 now - basetime);
2818 }
2819
2820 log(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
2821 fprintf(f, "%s %s %d %u %u\n",
2822 session[i].user, // username
2823 inet_toa(htonl(session[i].ip)), // ip
2824 (session[i].throttle) ? 2 : 1, // qos
2825 (u32)session[i].cin, // uptxoctets
2826 (u32)session[i].cout); // downrxoctets
2827
2828 session[i].pin = session[i].cin = 0;
2829 session[i].pout = session[i].cout = 0;
2830 }
2831
2832 if (f) fclose(f);
2833 }
2834
2835 // Main program
2836 int main(int argc, char *argv[])
2837 {
2838 int o;
2839
2840 _program_name = strdup(argv[0]);
2841
2842 time(&basetime); // start clock
2843
2844 // scan args
2845 while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
2846 {
2847 switch (o)
2848 {
2849 case 'd':
2850 // Double fork to detach from terminal
2851 if (fork()) exit(0);
2852 if (fork()) exit(0);
2853 break;
2854 case 'v':
2855 config->debug++;
2856 break;
2857 case 'h':
2858 snprintf(hostname, sizeof(hostname), "%s", optarg);
2859 break;
2860 case '?':
2861 default:
2862 printf("Args are:\n"
2863 "\t-d\tDetach from terminal\n"
2864 "\t-c <file>\tConfig file\n"
2865 "\t-h <hostname>\tForce hostname\n"
2866 "\t-a <address>\tUse specific address\n"
2867 "\t-v\t\tDebug\n");
2868
2869 return (0);
2870 break;
2871 }
2872 }
2873
2874 // Start the timer routine off
2875 time(&time_now);
2876 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
2877 signal(SIGALRM, sigalrm_handler);
2878 siginterrupt(SIGALRM, 0);
2879
2880 initiptables();
2881 initplugins();
2882 initdata();
2883 init_tbf();
2884 init_cli(hostname);
2885 read_config_file();
2886
2887 log(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
2888 log(0, 0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
2889 log(0, 0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
2890 {
2891 struct rlimit rlim;
2892 rlim.rlim_cur = RLIM_INFINITY;
2893 rlim.rlim_max = RLIM_INFINITY;
2894 // Remove the maximum core size
2895 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
2896 log(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
2897 // Make core dumps go to /tmp
2898 chdir("/tmp");
2899 }
2900
2901 if (config->scheduler_fifo)
2902 {
2903 int ret;
2904 struct sched_param params = {0};
2905 params.sched_priority = 1;
2906
2907 if (get_nprocs() < 2)
2908 {
2909 log(0, 0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
2910 config->scheduler_fifo = 0;
2911 }
2912 else
2913 {
2914 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
2915 {
2916 log(1, 0, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
2917 }
2918 else
2919 {
2920 log(0, 0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
2921 config->scheduler_fifo = 0;
2922 }
2923 }
2924 }
2925
2926 /* Set up the cluster communications port. */
2927 if (cluster_init(config->bind_address) < 0)
2928 exit(1);
2929
2930 #ifdef BGP
2931 signal(SIGPIPE, SIG_IGN);
2932 bgp_setup(config->as_number);
2933 bgp_add_route(config->bind_address, 0xffffffff);
2934 if (*config->bgp_peer[0])
2935 bgp_start(&bgp_peers[0], config->bgp_peer[0],
2936 config->bgp_peer_as[0], 0); /* 0 = routing disabled */
2937
2938 if (*config->bgp_peer[1])
2939 bgp_start(&bgp_peers[1], config->bgp_peer[1],
2940 config->bgp_peer_as[1], 0);
2941 #endif /* BGP */
2942
2943 inittun();
2944 log(1, 0, 0, 0, "Set up on interface %s\n", config->tundevice);
2945
2946 initudp();
2947 initrad();
2948 initippool();
2949
2950 read_state();
2951
2952 signal(SIGHUP, sighup_handler);
2953 signal(SIGTERM, sigterm_handler);
2954 signal(SIGINT, sigterm_handler);
2955 signal(SIGQUIT, sigquit_handler);
2956 signal(SIGCHLD, sigchild_handler);
2957
2958 alarm(1);
2959
2960 // Drop privileges here
2961 if (config->target_uid > 0 && geteuid() == 0)
2962 setuid(config->target_uid);
2963
2964 mainloop();
2965
2966 #ifdef BGP
2967 /* try to shut BGP down cleanly; with luck the sockets will be
2968 writable since we're out of the select */
2969 {
2970 int i;
2971 for (i = 0; i < BGP_NUM_PEERS; i++)
2972 if (bgp_peers[i].state == Established)
2973 bgp_stop(&bgp_peers[i]);
2974 }
2975 #endif /* BGP */
2976
2977 /* remove plugins (so cleanup code gets run) */
2978 plugins_done();
2979
2980 /* kill CLI children */
2981 signal(SIGTERM, SIG_IGN);
2982 kill(0, SIGTERM);
2983 return 0;
2984 }
2985
2986 void sighup_handler(int junk)
2987 {
2988 if (log_stream && log_stream != stderr)
2989 {
2990 fclose(log_stream);
2991 log_stream = NULL;
2992 }
2993
2994 read_config_file();
2995 }
2996
2997 void sigalrm_handler(int junk)
2998 {
2999 // Log current traffic stats
3000
3001 snprintf(config->bandwidth, sizeof(config->bandwidth),
3002 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3003 (udp_rx / 1024.0 / 1024.0 * 8),
3004 (eth_tx / 1024.0 / 1024.0 * 8),
3005 (eth_rx / 1024.0 / 1024.0 * 8),
3006 (udp_tx / 1024.0 / 1024.0 * 8),
3007 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3008 udp_rx_pkt, eth_rx_pkt);
3009
3010 udp_tx = udp_rx = 0;
3011 udp_rx_pkt = eth_rx_pkt = 0;
3012 eth_tx = eth_rx = 0;
3013
3014 if (config->dump_speed)
3015 printf("%s\n", config->bandwidth);
3016
3017 // Update the internal time counter
3018 time(&time_now);
3019 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3020 alarm(1);
3021
3022 {
3023 // Run timer hooks
3024 struct param_timer p = { time_now };
3025 run_plugins(PLUGIN_TIMER, &p);
3026 }
3027
3028 }
3029
3030 void sigterm_handler(int junk)
3031 {
3032 log(1, 0, 0, 0, "Shutting down cleanly\n");
3033 if (config->save_state)
3034 dump_state();
3035
3036 main_quit++;
3037 }
3038
3039 void sigquit_handler(int junk)
3040 {
3041 int i;
3042
3043 log(1, 0, 0, 0, "Shutting down without saving sessions\n");
3044 for (i = 1; i < MAXSESSION; i++)
3045 {
3046 if (session[i].opened)
3047 sessionkill(i, "L2TPNS Closing");
3048 }
3049 for (i = 1; i < MAXTUNNEL; i++)
3050 {
3051 if (tunnel[i].ip || tunnel[i].state)
3052 tunnelshutdown(i, "L2TPNS Closing");
3053 }
3054
3055 main_quit++;
3056 }
3057
3058 void sigchild_handler(int signal)
3059 {
3060 while (waitpid(-1, NULL, WNOHANG) > 0)
3061 ;
3062 }
3063
3064 void read_state()
3065 {
3066 struct stat sb;
3067 int i;
3068 ippoolt itmp;
3069 FILE *f;
3070 char magic[sizeof(DUMP_MAGIC)-1];
3071 u32 buf[2];
3072
3073 if (!config->save_state)
3074 {
3075 unlink(STATEFILE);
3076 return;
3077 }
3078
3079 if (stat(STATEFILE, &sb) < 0)
3080 {
3081 unlink(STATEFILE);
3082 return;
3083 }
3084
3085 if (sb.st_mtime < (time(NULL) - 60))
3086 {
3087 log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
3088 unlink(STATEFILE);
3089 return;
3090 }
3091
3092 f = fopen(STATEFILE, "r");
3093 unlink(STATEFILE);
3094
3095 if (!f)
3096 {
3097 log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3098 exit(1);
3099 }
3100
3101 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3102 {
3103 log(0, 0, 0, 0, "Bad state file magic\n");
3104 exit(1);
3105 }
3106
3107 log(1, 0, 0, 0, "Reading state information\n");
3108 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3109 {
3110 log(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3111 exit(1);
3112 }
3113
3114 if (buf[0] > ip_pool_size)
3115 {
3116 log(0, 0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3117 exit(1);
3118 }
3119
3120 log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
3121 for (i = 0; i < buf[0]; i++)
3122 {
3123 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3124 {
3125 log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3126 exit(1);
3127 }
3128
3129 if (itmp.address != ip_address_pool[i].address)
3130 {
3131 log(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3132 exit(1);
3133 }
3134
3135 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3136 }
3137
3138 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3139 {
3140 log(0, 0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3141 exit(1);
3142 }
3143
3144 log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3145 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3146 {
3147 log(0, 0, 0, 0, "Error reading tunnel data from state file\n");
3148 exit(1);
3149 }
3150
3151 for (i = 0; i < MAXTUNNEL; i++)
3152 {
3153 tunnel[i].controlc = 0;
3154 tunnel[i].controls = NULL;
3155 tunnel[i].controle = NULL;
3156 if (*tunnel[i].hostname)
3157 log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3158 }
3159
3160 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3161 {
3162 log(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
3163 exit(1);
3164 }
3165
3166 log(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
3167 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3168 {
3169 log(0, 0, 0, 0, "Error reading session data from state file\n");
3170 exit(1);
3171 }
3172
3173 for (i = 0; i < MAXSESSION; i++)
3174 {
3175 session[i].tbf_in = 0;
3176 session[i].tbf_out = 0;
3177 if (session[i].opened)
3178 {
3179 log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
3180 if (session[i].ip)
3181 sessionsetup(session[i].tunnel, i);
3182 }
3183 }
3184
3185 fclose(f);
3186 log(0, 0, 0, 0, "Loaded saved state information\n");
3187 }
3188
3189 void dump_state()
3190 {
3191 FILE *f;
3192 u32 buf[2];
3193
3194 if (!config->save_state)
3195 return;
3196
3197 do {
3198 if (!(f = fopen(STATEFILE, "w")))
3199 break;
3200
3201 log(1, 0, 0, 0, "Dumping state information\n");
3202
3203 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC)-1, 1, f) != 1) break;
3204
3205 log(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3206 buf[0] = ip_pool_size;
3207 buf[1] = sizeof(ippoolt);
3208 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3209 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size) break;
3210
3211 log(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3212 buf[0] = MAXTUNNEL;
3213 buf[1] = sizeof(tunnelt);
3214 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3215 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL) break;
3216
3217 log(2, 0, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3218 buf[0] = MAXSESSION;
3219 buf[1] = sizeof(sessiont);
3220 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3221 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION) break;
3222
3223 if (fclose(f) == 0) return; // OK
3224 } while (0);
3225
3226 log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3227 unlink(STATEFILE);
3228 }
3229
3230 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
3231 {
3232 MD5_CTX ctx;
3233 *challenge_response = NULL;
3234
3235 if (!*config->l2tpsecret)
3236 {
3237 log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3238 return;
3239 }
3240
3241 log(4, 0, 0, 0, " Building challenge response for CHAP request\n");
3242
3243 *challenge_response = (char *)calloc(17, 1);
3244
3245 MD5Init(&ctx);
3246 MD5Update(&ctx, &id, 1);
3247 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3248 MD5Update(&ctx, challenge, challenge_length);
3249 MD5Final(*challenge_response, &ctx);
3250
3251 return;
3252 }
3253
3254 static int facility_value(char *name)
3255 {
3256 int i;
3257 for (i = 0; facilitynames[i].c_name; i++)
3258 {
3259 if (strcmp(facilitynames[i].c_name, name) == 0)
3260 return facilitynames[i].c_val;
3261 }
3262 return 0;
3263 }
3264
3265 void update_config()
3266 {
3267 int i;
3268 static int timeout = 0;
3269 static int interval = 0;
3270
3271 // Update logging
3272 closelog();
3273 syslog_log = 0;
3274 if (log_stream)
3275 {
3276 fclose(log_stream);
3277 log_stream = NULL;
3278 }
3279 if (*config->log_filename)
3280 {
3281 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3282 {
3283 char *p = config->log_filename + 7;
3284 if (*p)
3285 {
3286 openlog("l2tpns", LOG_PID, facility_value(p));
3287 syslog_log = 1;
3288 }
3289 }
3290 else if (strchr(config->log_filename, '/') == config->log_filename)
3291 {
3292 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3293 {
3294 fseek(log_stream, 0, SEEK_END);
3295 setbuf(log_stream, NULL);
3296 }
3297 else
3298 {
3299 log_stream = stderr;
3300 setbuf(log_stream, NULL);
3301 }
3302 }
3303 }
3304 else
3305 {
3306 log_stream = stderr;
3307 setbuf(log_stream, NULL);
3308 }
3309
3310
3311 // Update radius
3312 config->numradiusservers = 0;
3313 for (i = 0; i < MAXRADSERVER; i++)
3314 if (config->radiusserver[i]) config->numradiusservers++;
3315
3316 if (!config->numradiusservers)
3317 {
3318 log(0, 0, 0, 0, "No RADIUS servers defined!\n");
3319 }
3320
3321 config->num_radfds = 2 << RADIUS_SHIFT;
3322
3323 // Update plugins
3324 for (i = 0; i < MAXPLUGINS; i++)
3325 {
3326 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3327 continue;
3328 if (*config->plugins[i])
3329 {
3330 // Plugin added
3331 add_plugin(config->plugins[i]);
3332 }
3333 else if (*config->old_plugins[i])
3334 {
3335 // Plugin removed
3336 remove_plugin(config->old_plugins[i]);
3337 }
3338 }
3339 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3340 if (!config->cleanup_interval) config->cleanup_interval = 10;
3341 if (!config->multi_read_count) config->multi_read_count = 10;
3342 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3343 if (!*config->cluster_interface)
3344 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3345
3346 if (!config->cluster_hb_interval)
3347 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3348
3349 if (!config->cluster_hb_timeout)
3350 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3351
3352 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3353 {
3354 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3355 // late, ensure we're sufficiently larger than that
3356 int t = 4 * config->cluster_hb_interval + 11;
3357
3358 if (config->cluster_hb_timeout < t)
3359 {
3360 log(0,0,0,0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3361 config->cluster_hb_timeout = t;
3362 }
3363
3364 // Push timing changes to the slaves immediately if we're the master
3365 if (config->cluster_iam_master)
3366 cluster_heartbeat();
3367
3368 interval = config->cluster_hb_interval;
3369 timeout = config->cluster_hb_timeout;
3370 }
3371
3372 config->reload_config = 0;
3373 }
3374
3375 void read_config_file()
3376 {
3377 FILE *f;
3378
3379 if (!config->config_file) return;
3380 if (!(f = fopen(config->config_file, "r"))) {
3381 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3382 return;
3383 }
3384
3385 log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
3386 cli_do_file(f);
3387 log(3, 0, 0, 0, "Done reading config file\n");
3388 fclose(f);
3389 update_config();
3390 }
3391
3392 int sessionsetup(tunnelidt t, sessionidt s)
3393 {
3394 // A session now exists, set it up
3395 ipt ip;
3396 char *user;
3397 sessionidt i;
3398 int r;
3399
3400 CSTAT(call_sessionsetup);
3401
3402
3403 log(3, session[s].ip, s, t, "Doing session setup for session\n");
3404
3405 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3406 {
3407 assign_ip_address(s);
3408 if (session[s].ip)
3409 log(3, 0, s, t, " No IP allocated. Assigned %s from pool\n",
3410 inet_toa(htonl(session[s].ip)));
3411 else
3412 log(0, 0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3413 }
3414
3415
3416 // Make sure this is right
3417 session[s].tunnel = t;
3418
3419 // zap old sessions with same IP and/or username
3420 // Don't kill gardened sessions - doing so leads to a DoS
3421 // from someone who doesn't need to know the password
3422 {
3423 ip = session[s].ip;
3424 user = session[s].user;
3425 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3426 {
3427 if (i == s) continue;
3428 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3429 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3430 sessionkill(i, "Duplicate session for users");
3431 }
3432 }
3433
3434 // Add the route for this session.
3435 //
3436 // Static IPs need to be routed. Anything else
3437 // is part of the IP address pool and is already routed,
3438 // it just needs to be added to the IP cache.
3439 if (session[s].ip_pool_index == -1) // static ip
3440 routeset(s, session[s].ip, 0, 0, 1);
3441 else
3442 cache_ipmap(session[s].ip, s);
3443
3444 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3445 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1);
3446
3447 if (!session[s].sid) { // did this session just finish radius?
3448 log(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
3449 sendipcp(t, s);
3450 session[s].sid = ++last_sid;
3451 }
3452
3453 // Run the plugin's against this new session.
3454 {
3455 struct param_new_session data = { &tunnel[t], &session[s] };
3456 run_plugins(PLUGIN_NEW_SESSION, &data);
3457 }
3458
3459 // Force throttling on or off (Actually : refresh the current throttling status)
3460 // This has the advantage of cleaning up after another throttled user who may have left
3461 // firewall rules lying around
3462 throttle_session(s, session[s].throttle);
3463
3464 session[s].last_packet = time_now;
3465
3466 {
3467 char *sessionip, *tunnelip;
3468 sessionip = strdup(inet_toa(htonl(session[s].ip)));
3469 tunnelip = strdup(inet_toa(htonl(tunnel[t].ip)));
3470 log(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
3471 session[s].user, sessionip, tunnelip, tunnel[t].hostname);
3472 if (sessionip) free(sessionip);
3473 if (tunnelip) free(tunnelip);
3474 }
3475
3476 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3477
3478 return 1; // RADIUS OK and IP allocated, done...
3479 }
3480
3481 //
3482 // This session just got dropped on us by the master or something.
3483 // Make sure our tables up up to date...
3484 //
3485 int load_session(sessionidt s, sessiont *new)
3486 {
3487 int i;
3488
3489 // Sanity checks.
3490 if (new->ip_pool_index >= MAXIPPOOL ||
3491 new->tunnel >= MAXTUNNEL) {
3492 log(0,0,s,0, "Strange session update received!\n");
3493 // FIXME! What to do here?
3494 return 0;
3495 }
3496
3497 //
3498 // Ok. All sanity checks passed. Now we're committed to
3499 // loading the new session.
3500 //
3501
3502 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3503
3504
3505 if (new->ip != session[s].ip) // Changed ip. fix up hash tables.
3506 {
3507 if (session[s].ip) // If there's an old one, remove it.
3508 {
3509 // Remove any routes if the IP has changed
3510 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3511 {
3512 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3513 session[s].route[i].ip = 0;
3514 }
3515
3516 if (session[s].ip_pool_index == -1) // static IP
3517 routeset(s, session[s].ip, 0, 0, 0);
3518 else // It's part of the IP pool, remove it manually.
3519 uncache_ipmap(session[s].ip);
3520 }
3521
3522 if (new->ip) { // If there's a new one, add it.
3523 if (new->ip_pool_index == -1)
3524 routeset(s, new->ip, 0, 0, 1);
3525 else
3526 cache_ipmap(new->ip, s);
3527 }
3528 }
3529
3530 // Update routed networks
3531 for (i = 0; i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3532 {
3533 if (new->route[i].ip == session[s].route[i].ip &&
3534 new->route[i].mask == session[s].route[i].mask)
3535 continue;
3536
3537 if (session[s].route[i].ip) // Remove the old one if it exists.
3538 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3539
3540 if (new->route[i].ip) // Add the new one if it exists.
3541 routeset(s, new->route[i].ip, new->route[i].mask, new->ip, 1);
3542 }
3543
3544 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3545 // for walking the sessions to forward byte counts to the master.
3546 config->cluster_highest_sessionid = s;
3547
3548 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3549
3550 // Do fixups into address pool.
3551 if (new->ip_pool_index != -1)
3552 fix_address_pool(s);
3553
3554 return 1;
3555 }
3556
3557 #ifdef RINGBUFFER
3558 void ringbuffer_dump(FILE *stream)
3559 {
3560 int i = ringbuffer->head;
3561
3562 while (i != ringbuffer->tail)
3563 {
3564 if (*ringbuffer->buffer[i].message)
3565 fprintf(stream, "%d-%s", ringbuffer->buffer[i].level, ringbuffer->buffer[i].message);
3566 if (++i == ringbuffer->tail) break;
3567 if (i == RINGBUFFER_SIZE) i = 0;
3568 }
3569 }
3570 #endif
3571
3572 void initplugins()
3573 {
3574 int i;
3575
3576 loaded_plugins = ll_init();
3577 // Initialize the plugins to nothing
3578 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3579 plugins[i] = ll_init();
3580 }
3581
3582 static void *open_plugin(char *plugin_name, int load)
3583 {
3584 char path[256] = "";
3585
3586 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3587 log(2, 0, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3588 return dlopen(path, RTLD_NOW);
3589 }
3590
3591 void add_plugin(char *plugin_name)
3592 {
3593 static struct pluginfuncs funcs = {
3594 _log,
3595 _log_hex,
3596 inet_toa,
3597 sessionbyuser,
3598 sessiontbysessionidt,
3599 sessionidtbysessiont,
3600 sessionkill,
3601 radiusnew,
3602 radiussend,
3603 };
3604
3605 void *p = open_plugin(plugin_name, 1);
3606 int (*initfunc)(struct pluginfuncs *);
3607 int i;
3608
3609 if (!p)
3610 {
3611 log(1, 0, 0, 0, " Plugin load failed: %s\n", dlerror());
3612 return;
3613 }
3614
3615 if (ll_contains(loaded_plugins, p))
3616 {
3617 dlclose(p);
3618 return;
3619 }
3620
3621 {
3622 int *v = dlsym(p, "__plugin_api_version");
3623 if (!v || *v != PLUGIN_API_VERSION)
3624 {
3625 log(1, 0, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
3626 dlclose(p);
3627 return;
3628 }
3629 }
3630
3631 if ((initfunc = dlsym(p, "plugin_init")))
3632 {
3633 if (!initfunc(&funcs))
3634 {
3635 log(1, 0, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
3636 dlclose(p);
3637 return;
3638 }
3639 }
3640
3641 ll_push(loaded_plugins, p);
3642
3643 for (i = 0; i < max_plugin_functions; i++)
3644 {
3645 void *x;
3646 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3647 {
3648 log(3, 0, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
3649 ll_push(plugins[i], x);
3650 }
3651 }
3652
3653 log(2, 0, 0, 0, " Loaded plugin %s\n", plugin_name);
3654 }
3655
3656 static void run_plugin_done(void *plugin)
3657 {
3658 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
3659
3660 if (donefunc)
3661 donefunc();
3662 }
3663
3664 void remove_plugin(char *plugin_name)
3665 {
3666 void *p = open_plugin(plugin_name, 0);
3667 int i;
3668
3669 if (!p)
3670 return;
3671
3672 for (i = 0; i < max_plugin_functions; i++)
3673 {
3674 void *x;
3675 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3676 ll_delete(plugins[i], x);
3677 }
3678
3679 if (ll_contains(loaded_plugins, p))
3680 {
3681 ll_delete(loaded_plugins, p);
3682 run_plugin_done(p);
3683 }
3684
3685 dlclose(p);
3686 log(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
3687 }
3688
3689 int run_plugins(int plugin_type, void *data)
3690 {
3691 int (*func)(void *data);
3692 if (!plugins[plugin_type] || plugin_type > max_plugin_functions) return 1;
3693
3694 ll_reset(plugins[plugin_type]);
3695 while ((func = ll_next(plugins[plugin_type])))
3696 {
3697 int rc;
3698 rc = func(data);
3699 if (rc == PLUGIN_RET_STOP) return 1;
3700 if (rc == PLUGIN_RET_ERROR) return 0;
3701 }
3702 return 1;
3703 }
3704
3705 void plugins_done()
3706 {
3707 void *p;
3708
3709 ll_reset(loaded_plugins);
3710 while ((p = ll_next(loaded_plugins)))
3711 run_plugin_done(p);
3712 }
3713
3714 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
3715 {
3716 char *resp;
3717 int l;
3718 struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
3719
3720
3721 if (log_stream && config->debug >= 4)
3722 {
3723 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
3724 dump_packet(buf, log_stream);
3725 }
3726
3727 resp = calloc(1400, 1);
3728 l = new_packet(PKT_RESP_ERROR, resp);
3729 *(int *)(resp + 6) = *(int *)(buf + 6);
3730
3731 param.type = ntohs(*(short *)(buf + 2));
3732 param.id = ntohl(*(int *)(buf + 6));
3733 param.data_length = ntohs(*(short *)(buf + 4)) - 10;
3734 param.data = (param.data_length > 0) ? (char *)(buf + 10) : NULL;
3735 param.response = resp;
3736 param.response_length = l;
3737
3738 run_plugins(PLUGIN_CONTROL, &param);
3739
3740 if (param.send_response)
3741 {
3742 send_packet(controlfd, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), param.response, param.response_length);
3743 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent Control packet response\n");
3744 }
3745
3746 free(resp);
3747 }
3748
3749 /*
3750 * HACK
3751 * Go through all of the tunnels and do some cleanups
3752 */
3753 void tunnel_clean()
3754 {
3755 int i;
3756
3757 log(1, 0, 0, 0, "Cleaning tunnels array\n");
3758
3759 for (i = 1; i < MAXTUNNEL; i++)
3760 {
3761 if (!tunnel[i].ip
3762 || !*tunnel[i].hostname
3763 || (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
3764 {
3765 tunnelclear(i);
3766 }
3767 }
3768 }
3769
3770 void tunnelclear(tunnelidt t)
3771 {
3772 if (!t) return;
3773 memset(&tunnel[t], 0, sizeof(tunnel[t]));
3774 tunnel[t].state = TUNNELFREE;
3775 }
3776
3777 tunnelidt new_tunnel()
3778 {
3779 tunnelidt i;
3780 for (i = 1; i < MAXTUNNEL; i++)
3781 {
3782 if (tunnel[i].state == TUNNELFREE)
3783 {
3784 log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
3785 if (i > config->cluster_highest_tunnelid)
3786 config->cluster_highest_tunnelid = i;
3787 return i;
3788 }
3789 }
3790 log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
3791 return 0;
3792 }
3793
3794 //
3795 // We're becoming the master. Do any required setup..
3796 //
3797 // This is principally telling all the plugins that we're
3798 // now a master, and telling them about all the sessions
3799 // that are active too..
3800 //
3801 void become_master(void)
3802 {
3803 int s;
3804 run_plugins(PLUGIN_BECOME_MASTER, NULL);
3805
3806 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3807 if (!session[s].tunnel) // Not an in-use session.
3808 continue;
3809
3810 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
3811 }
3812 }
3813
3814
3815
3816 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
3817 {
3818 int s, i;
3819 int count = 0;
3820 int buckets[64];
3821
3822 if (CLI_HELP_REQUESTED)
3823 return CLI_HELP_NO_ARGS;
3824
3825 time(&time_now);
3826 for (i = 0; i < 64;++i) buckets[i] = 0;
3827
3828 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3829 int idle;
3830 if (!session[s].tunnel)
3831 continue;
3832
3833 idle = time_now - session[s].last_packet;
3834 idle /= 5 ; // In multiples of 5 seconds.
3835 if (idle < 0)
3836 idle = 0;
3837 if (idle > 63)
3838 idle = 63;
3839
3840 ++count;
3841 ++buckets[idle];
3842 }
3843
3844 for (i = 0; i < 63; ++i) {
3845 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
3846 }
3847 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
3848 cli_print(cli, "%d total sessions open.", count);
3849 return CLI_OK;
3850 }
3851
3852 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
3853 {
3854 int s, i;
3855 int count = 0;
3856 int buckets[64];
3857
3858 if (CLI_HELP_REQUESTED)
3859 return CLI_HELP_NO_ARGS;
3860
3861 time(&time_now);
3862 for (i = 0; i < 64;++i) buckets[i] = 0;
3863
3864 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3865 int open = 0, d;
3866 if (!session[s].tunnel)
3867 continue;
3868
3869 d = time_now - session[s].opened;
3870 if (d < 0)
3871 d = 0;
3872 while (d > 1 && open < 32) {
3873 ++open;
3874 d >>= 1; // half.
3875 }
3876 ++count;
3877 ++buckets[open];
3878 }
3879
3880 s = 1;
3881 for (i = 0; i < 30; ++i) {
3882 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
3883 s <<= 1;
3884 }
3885 cli_print(cli, "%d total sessions open.", count);
3886 return CLI_OK;
3887 }