1abe8ace9539577f4de646ea59968484c708b397
[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 1.18 2004/07/28 06:12:30 fred_nerk Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <stdarg.h>
23 #include <stdlib.h>
24 #include <stdio.h>
25 #include <string.h>
26 #include <sys/ioctl.h>
27 #include <sys/socket.h>
28 #include <sys/stat.h>
29 #include <sys/time.h>
30 #include <sys/resource.h>
31 #include <sys/wait.h>
32 #include <linux/if.h>
33 #include <stddef.h>
34 #include <time.h>
35 #include <dlfcn.h>
36 #include <unistd.h>
37 #include <sched.h>
38 #include <sys/sysinfo.h>
39 #include <libcli.h>
40
41 #include "md5.h"
42 #include "l2tpns.h"
43 #include "cluster.h"
44 #include "plugin.h"
45 #include "ll.h"
46 #include "constants.h"
47 #include "control.h"
48 #include "util.h"
49 #include "tbf.h"
50
51 // Globals
52 struct configt *config = NULL; // all configuration
53 int tunfd = -1; // tun interface file handle. (network device)
54 int udpfd = -1; // UDP file handle
55 int controlfd = -1; // Control signal handle
56 int snoopfd = -1; // UDP file handle for sending out intercept data
57 int *radfds = NULL; // RADIUS requests file handles
58 int ifrfd = -1; // File descriptor for routing, etc
59 time_t basetime = 0; // base clock
60 char hostname[1000] = ""; // us.
61 int tunidx; // ifr_ifindex of tun device
62 u32 sessionid = 0; // session id for radius accounting
63 int syslog_log = 0; // are we logging to syslog
64 FILE *log_stream = NULL; // file handle for direct logging (i.e. direct into file, not via syslog).
65 extern int cluster_sockfd; // Intra-cluster communications socket.
66 u32 last_sid = 0; // Last used PPP SID. Can I kill this?? -- mo
67 int clifd = 0; // Socket listening for CLI connections.
68
69 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
70 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
71
72 static void *ip_hash[256]; // Mapping from IP address to session structures.
73
74 u32 udp_tx = 0, udp_rx = 0, udp_rx_pkt = 0; // Global traffic counters.
75 u32 eth_tx = 0, eth_rx = 0, eth_rx_pkt = 0;
76 u32 ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
77 time_t time_now = 0; // Current time in seconds since epoch.
78 char time_now_string[64] = {0}; // Current time as a string.
79 char main_quit = 0; // True if we're in the process of exiting.
80 char *_program_name = NULL;
81 linked_list *loaded_plugins;
82 linked_list *plugins[MAX_PLUGIN_TYPES];
83
84 #ifdef BGP
85 #include "bgp.h"
86 struct bgp_peer *bgp_peers = 0;
87 struct bgp_route_list *bgp_routes = 0;
88 int bgp_configured = 0;
89 #endif /* BGP */
90
91 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
92 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(struct configt, MEMBER), membersize(struct configt, MEMBER), TYPE }
93
94 struct config_descriptt config_values[] = {
95 CONFIG("debug", debug, INT),
96 CONFIG("log_file", log_filename, STRING),
97 CONFIG("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("primary_radius_port",radiusport[0], SHORT),
104 CONFIG("secondary_radius_port",radiusport[1], SHORT),
105 CONFIG("radius_accounting", radius_accounting, BOOL),
106 CONFIG("radius_secret", radiussecret, STRING),
107 CONFIG("bind_address", bind_address, IP),
108 CONFIG("send_garp", send_garp, BOOL),
109 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
110 CONFIG("accounting_dir", accounting_dir, STRING),
111 CONFIG("setuid", target_uid, INT),
112 CONFIG("dump_speed", dump_speed, BOOL),
113 CONFIG("cleanup_interval", cleanup_interval, INT),
114 CONFIG("multi_read_count", multi_read_count, INT),
115 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
116 CONFIG("lock_pages", lock_pages, BOOL),
117 CONFIG("icmp_rate", icmp_rate, INT),
118 CONFIG("cluster_address", cluster_address, IP),
119 CONFIG("cluster_interface", cluster_interface, STRING),
120 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
121 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
122 #ifdef BGP
123 CONFIG("as_number", as_number, SHORT),
124 CONFIG("bgp_peer1", bgp_peer[0], STRING),
125 CONFIG("bgp_peer1_as", bgp_peer_as[0], SHORT),
126 CONFIG("bgp_peer2", bgp_peer[1], STRING),
127 CONFIG("bgp_peer2_as", bgp_peer_as[1], SHORT),
128 #endif /* BGP */
129 { NULL, 0, 0, 0 },
130 };
131
132 char *plugin_functions[] = {
133 NULL,
134 "plugin_pre_auth",
135 "plugin_post_auth",
136 "plugin_packet_rx",
137 "plugin_packet_tx",
138 "plugin_timer",
139 "plugin_new_session",
140 "plugin_kill_session",
141 "plugin_control",
142 "plugin_radius_response",
143 "plugin_become_master",
144 "plugin_new_session_master",
145 };
146
147 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
148
149 tunnelt *tunnel = NULL; // Array of tunnel structures.
150 sessiont *session = NULL; // Array of session structures.
151 sessioncountt *sess_count = NULL; // Array of partial per-session traffic counters.
152 radiust *radius = NULL; // Array of radius structures.
153 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
154 controlt *controlfree = 0;
155 struct Tstats *_statistics = NULL;
156 #ifdef RINGBUFFER
157 struct Tringbuffer *ringbuffer = NULL;
158 #endif
159
160 void sigalrm_handler(int);
161 void sighup_handler(int);
162 void sigterm_handler(int);
163 void sigquit_handler(int);
164 void sigchild_handler(int);
165 void read_config_file();
166 void read_state();
167 void dump_state();
168 void tunnel_clean();
169 tunnelidt new_tunnel();
170 void update_config();
171
172 static void cache_ipmap(ipt ip, int s);
173 static void uncache_ipmap(ipt ip);
174
175 // return internal time (10ths since process startup)
176 clockt now(void)
177 {
178 struct timeval t;
179 gettimeofday(&t, 0);
180 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
181 }
182
183 // work out a retry time based on try number
184 // This is a straight bounded exponential backoff.
185 // Maximum re-try time is 32 seconds. (2^5).
186 clockt backoff(u8 try)
187 {
188 if (try > 5) try = 5; // max backoff
189 return now() + 10 * (1 << try);
190 }
191
192
193 //
194 // Log a debug message.
195 //
196 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
197 {
198 static char message[65536] = {0};
199 static char message2[65536] = {0};
200 va_list ap;
201
202 #ifdef RINGBUFFER
203 if (ringbuffer)
204 {
205 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
206 ringbuffer->tail = 0;
207 if (ringbuffer->tail == ringbuffer->head)
208 if (++ringbuffer->head >= RINGBUFFER_SIZE)
209 ringbuffer->head = 0;
210
211 ringbuffer->buffer[ringbuffer->tail].level = level;
212 ringbuffer->buffer[ringbuffer->tail].address = address;
213 ringbuffer->buffer[ringbuffer->tail].session = s;
214 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
215 va_start(ap, format);
216 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
217 va_end(ap);
218 }
219 #endif
220
221 if (config->debug < level) return;
222
223 va_start(ap, format);
224 if (log_stream)
225 {
226 vsnprintf(message2, 65535, format, ap);
227 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
228 fprintf(log_stream, "%s", message);
229 }
230 else if (syslog_log)
231 {
232 vsnprintf(message2, 65535, format, ap);
233 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
234 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
235 }
236 va_end(ap);
237 }
238
239 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize)
240 {
241 int i, j;
242 const u8 *d = (const u8 *)data;
243
244 if (config->debug < level) return;
245
246 // No support for log_hex to syslog
247 if (log_stream)
248 {
249 log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
250 setvbuf(log_stream, NULL, _IOFBF, 16384);
251
252 for (i = 0; i < maxsize; )
253 {
254 fprintf(log_stream, "%4X: ", i);
255 for (j = i; j < maxsize && j < (i + 16); j++)
256 {
257 fprintf(log_stream, "%02X ", d[j]);
258 if (j == i + 7)
259 fputs(": ", log_stream);
260 }
261
262 for (; j < i + 16; j++)
263 {
264 fputs(" ", log_stream);
265 if (j == i + 7)
266 fputs(": ", log_stream);
267 }
268
269 fputs(" ", log_stream);
270 for (j = i; j < maxsize && j < (i + 16); j++)
271 {
272 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
273 fputc(d[j], log_stream);
274 else
275 fputc('.', log_stream);
276
277 if (j == i + 7)
278 fputs(" ", log_stream);
279 }
280
281 i = j;
282 fputs("\n", log_stream);
283 }
284
285 fflush(log_stream);
286 setbuf(log_stream, NULL);
287 }
288 }
289
290
291 // Add a route
292 //
293 // This adds it to the routing table, advertises it
294 // via iBGP if enabled, and stuffs it into the
295 // 'sessionbyip' cache.
296 //
297 // 'ip' and 'mask' must be in _host_ order.
298 //
299 void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
300 {
301 struct rtentry r;
302 int i;
303
304 if (!mask) mask = 0xffffffff;
305
306 ip &= mask; // Force the ip to be the first one in the route.
307
308 memset(&r, 0, sizeof(r));
309 r.rt_dev = config->tundevice;
310 r.rt_dst.sa_family = AF_INET;
311 *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
312 r.rt_gateway.sa_family = AF_INET;
313 *(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
314 r.rt_genmask.sa_family = AF_INET;
315 *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
316 r.rt_flags = (RTF_UP | RTF_STATIC);
317 if (gw)
318 r.rt_flags |= RTF_GATEWAY;
319 else if (mask == 0xffffffff)
320 r.rt_flags |= RTF_HOST;
321
322 log(1, ip, 0, 0, "Route %s %u.%u.%u.%u/%u.%u.%u.%u %u.%u.%u.%u\n",
323 add ? "add" : "del",
324 ip >> 24, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff,
325 mask >> 24, mask >> 16 & 0xff, mask >> 8 & 0xff, mask & 0xff,
326 gw >> 24, gw >> 16 & 0xff, gw >> 8 & 0xff, gw & 0xff);
327
328 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
329 log(0, 0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
330
331 #ifdef BGP
332 if (add)
333 bgp_add_route(htonl(ip), htonl(mask));
334 else
335 bgp_del_route(htonl(ip), htonl(mask));
336 #endif /* BGP */
337
338 // Add/Remove the IPs to the 'sessionbyip' cache.
339 // Note that we add the zero address in the case of
340 // a network route. Roll on CIDR.
341
342 // Note that 's == 0' implies this is the address pool.
343 // We still cache it here, because it will pre-fill
344 // the malloc'ed tree.
345
346 if (s)
347 {
348 if (!add) // Are we deleting a route?
349 s = 0; // Caching the session as '0' is the same as uncaching.
350
351 for (i = ip; (i&mask) == (ip&mask) ; ++i)
352 cache_ipmap(i, s);
353 }
354 }
355
356 //
357 // Set up TUN interface
358 void inittun(void)
359 {
360 struct ifreq ifr;
361 struct sockaddr_in sin = {0};
362 memset(&ifr, 0, sizeof(ifr));
363 ifr.ifr_flags = IFF_TUN;
364
365 tunfd = open(TUNDEVICE, O_RDWR);
366 if (tunfd < 0)
367 { // fatal
368 log(0, 0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
369 exit(1);
370 }
371 {
372 int flags = fcntl(tunfd, F_GETFL, 0);
373 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
374 }
375 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
376 {
377 log(0, 0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
378 exit(1);
379 }
380 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
381 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
382 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
383
384 sin.sin_family = AF_INET;
385 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
386 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
387
388 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
389 {
390 log(0, 0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
391 exit(1);
392 }
393 /* Bump up the qlen to deal with bursts from the network */
394 ifr.ifr_qlen = 1000;
395 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
396 {
397 log(0, 0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
398 exit(1);
399 }
400 ifr.ifr_flags = IFF_UP;
401 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
402 {
403 log(0, 0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
404 exit(1);
405 }
406 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
407 {
408 log(0, 0, 0, 0, "Error setting tun ifindex: %s\n", strerror(errno));
409 exit(1);
410 }
411 tunidx = ifr.ifr_ifindex;
412 }
413
414 // set up UDP port
415 void initudp(void)
416 {
417 int on = 1;
418 struct sockaddr_in addr;
419
420 // Tunnel
421 memset(&addr, 0, sizeof(addr));
422 addr.sin_family = AF_INET;
423 addr.sin_port = htons(L2TPPORT);
424 addr.sin_addr.s_addr = config->bind_address;
425 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
426 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
427 {
428 int flags = fcntl(udpfd, F_GETFL, 0);
429 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
430 }
431 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
432 {
433 log(0, 0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
434 exit(1);
435 }
436 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
437
438 // Control
439 memset(&addr, 0, sizeof(addr));
440 addr.sin_family = AF_INET;
441 addr.sin_port = htons(1702);
442 controlfd = socket(AF_INET, SOCK_DGRAM, 17);
443 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
444 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
445 {
446 log(0, 0, 0, 0, "Error in control bind: %s\n", strerror(errno));
447 exit(1);
448 }
449 }
450
451 //
452 // Find session by IP, < 1 for not found
453 //
454 // Confusingly enough, this 'ip' must be
455 // in _network_ order. This being the common
456 // case when looking it up from IP packet headers.
457 //
458 // We actually use this cache for two things.
459 // #1. For used IP addresses, this maps to the
460 // session ID that it's used by.
461 // #2. For un-used IP addresses, this maps to the
462 // index into the pool table that contains that
463 // IP address.
464 //
465
466 int lookup_ipmap(ipt ip)
467 {
468 u8 *a = (u8 *)&ip;
469 char **d = (char **) ip_hash;
470 int s;
471
472 if (!(d = (char **) d[(size_t) *a++])) return 0;
473 if (!(d = (char **) d[(size_t) *a++])) return 0;
474 if (!(d = (char **) d[(size_t) *a++])) return 0;
475
476 s = (ipt) d[(size_t) *a];
477 return s;
478 }
479
480 sessionidt sessionbyip(ipt ip)
481 {
482 int s = lookup_ipmap(ip);
483 CSTAT(call_sessionbyip);
484
485 if (s > 0 && s < MAXSESSION && session[s].tunnel)
486 return s;
487 return 0;
488 }
489
490 //
491 // Take an IP address in HOST byte order and
492 // add it to the sessionid by IP cache.
493 //
494 // (It's actually cached in network order)
495 //
496 static void cache_ipmap(ipt ip, int s)
497 {
498 ipt nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char*)(&ip))[0]
499 u8 *a = (u8 *) &nip;
500 char **d = (char **) ip_hash;
501 int i;
502
503 for (i = 0; i < 3; i++)
504 {
505 if (!d[(size_t) a[i]])
506 {
507 if (!(d[(size_t) a[i]] = calloc(256, sizeof (void *))))
508 return;
509 }
510
511 d = (char **) d[(size_t) a[i]];
512 }
513
514 d[(size_t) a[3]] = (char *)((int)s);
515
516 if (s > 0)
517 log(4, ip, s, session[s].tunnel, "Caching ip address %s\n", inet_toa(nip));
518 else if (s == 0)
519 log(4, ip, 0, 0, "Un-caching ip address %s\n", inet_toa(nip));
520 // else a map to an ip pool index.
521 }
522
523 static void uncache_ipmap(ipt ip)
524 {
525 cache_ipmap(ip, 0); // Assign it to the NULL session.
526 }
527
528 //
529 // CLI list to dump current ipcache.
530 //
531 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
532 {
533 char **d = (char **) ip_hash, **e, **f, **g;
534 int i, j, k, l;
535 int count = 0;
536
537 if (CLI_HELP_REQUESTED)
538 return CLI_HELP_NO_ARGS;
539
540 cli_print(cli, "%7s %s", "Sess#", "IP Address");
541
542 for (i = 0; i < 256; ++i) {
543 if (!d[i]) continue;
544 e = (char**) d[i];
545 for (j = 0; j < 256; ++j) {
546 if (!e[j]) continue;
547 f = (char**) e[j];
548 for (k = 0; k < 256; ++k) {
549 if (!f[k]) continue;
550 g = (char**)f[k];
551 for (l = 0; l < 256; ++l) {
552 if (!g[l]) continue;
553 cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
554 ++count;
555 }
556 }
557 }
558 }
559 cli_print(cli, "%d entries in cache", count);
560 return CLI_OK;
561 }
562
563
564 // Find session by username, 0 for not found
565 // walled garden users aren't authenticated, so the username is
566 // reasonably useless. Ignore them to avoid incorrect actions
567 //
568 // This is VERY inefficent. Don't call it often. :)
569 //
570 sessionidt sessionbyuser(char *username)
571 {
572 int s;
573 CSTAT(call_sessionbyuser);
574
575 for (s = 1; s < MAXSESSION ; ++s) {
576 if (session[s].walled_garden)
577 continue; // Skip walled garden users.
578
579 if (!strncmp(session[s].user, username, 128))
580 return s;
581
582 }
583 return 0; // Not found.
584 }
585
586 void send_garp(ipt ip)
587 {
588 int s;
589 struct ifreq ifr;
590 u8 mac[6];
591
592 s = socket(PF_INET, SOCK_DGRAM, 0);
593 if (s < 0)
594 {
595 log(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
596 return;
597 }
598 memset(&ifr, 0, sizeof(ifr));
599 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
600 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
601 {
602 log(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
603 close(s);
604 return;
605 }
606 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
607 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
608 {
609 log(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
610 close(s);
611 return;
612 }
613 close(s);
614 sendarp(ifr.ifr_ifindex, mac, ip);
615 }
616
617 // Find session by username, 0 for not found
618 sessiont *sessiontbysessionidt(sessionidt s)
619 {
620 if (!s || s > MAXSESSION) return NULL;
621 return &session[s];
622 }
623
624 sessionidt sessionidtbysessiont(sessiont *s)
625 {
626 sessionidt val = s-session;
627 if (s < session || val > MAXSESSION) return 0;
628 return val;
629 }
630
631 // actually send a control message for a specific tunnel
632 void tunnelsend(u8 * buf, u16 l, tunnelidt t)
633 {
634 struct sockaddr_in addr;
635
636 CSTAT(call_tunnelsend);
637
638 if (!t)
639 {
640 static int backtrace_count = 0;
641 log(0, 0, 0, t, "tunnelsend called with 0 as tunnel id\n");
642 STAT(tunnel_tx_errors);
643 log_backtrace(backtrace_count, 5)
644 return;
645 }
646
647 if (!tunnel[t].ip)
648 {
649 static int backtrace_count = 0;
650 log(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
651 log_backtrace(backtrace_count, 5)
652 STAT(tunnel_tx_errors);
653 return;
654 }
655 memset(&addr, 0, sizeof(addr));
656 addr.sin_family = AF_INET;
657 *(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
658 addr.sin_port = htons(tunnel[t].port);
659
660 // sequence expected, if sequence in message
661 if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
662
663 // If this is a control message, deal with retries
664 if (*buf & 0x80)
665 {
666 tunnel[t].last = time_now; // control message sent
667 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
668 if (tunnel[t].try > 1)
669 {
670 STAT(tunnel_retries);
671 log(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
672 }
673 }
674
675 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
676 {
677 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",
678 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
679 STAT(tunnel_tx_errors);
680 return;
681 }
682
683 log_hex(5, "Send Tunnel Data", buf, l);
684 STAT(tunnel_tx_packets);
685 INC_STAT(tunnel_tx_bytes, l);
686 }
687
688 //
689 // Tiny helper function to write data to
690 // the 'tun' device.
691 //
692 int tun_write(u8 * data, int size)
693 {
694 return write(tunfd, data, size);
695 }
696
697 // process outgoing (to tunnel) IP
698 //
699 void processipout(u8 * buf, int len)
700 {
701 sessionidt s;
702 sessiont *sp;
703 tunnelidt t;
704 ipt ip;
705
706 char * data = buf; // Keep a copy of the originals.
707 int size = len;
708
709 u8 b[MAXETHER + 20];
710
711 CSTAT(call_processipout);
712
713 if (len < MIN_IP_SIZE)
714 {
715 log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
716 STAT(tunnel_tx_errors);
717 return;
718 }
719 if (len >= MAXETHER)
720 {
721 log(1, 0, 0, 0, "Oversize IP packet %d bytes\n", len);
722 STAT(tunnel_tx_errors);
723 return;
724 }
725
726 // Skip the tun header
727 buf += 4;
728 len -= 4;
729
730 // Got an IP header now
731 if (*(u8 *)(buf) >> 4 != 4)
732 {
733 log(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
734 return;
735 }
736
737 ip = *(u32 *)(buf + 16);
738 if (!(s = sessionbyip(ip)))
739 {
740 // Is this a packet for a session that doesn't exist?
741 static int rate = 0; // Number of ICMP packets we've sent this second.
742 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
743
744 if (last != time_now) {
745 last = time_now;
746 rate = 0;
747 }
748
749 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
750 {
751 log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
752 host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
753 }
754 return;
755 }
756 t = session[s].tunnel;
757 sp = &session[s];
758
759 if (sp->tbf_out)
760 {
761 // Are we throttling this session?
762 if (config->cluster_iam_master)
763 tbf_queue_packet(sp->tbf_out, data, size);
764 else
765 master_throttle_packet(sp->tbf_out, data, size);
766 return;
767 }
768 else if (sp->walled_garden && !config->cluster_iam_master)
769 {
770 // We are walled-gardening this
771 master_garden_packet(s, data, size);
772 return;
773 }
774
775 // Snooping this session, send it to intercept box
776 if (sp->snoop_ip && sp->snoop_port)
777 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
778
779 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
780
781 // Add on L2TP header
782 {
783 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
784 if (!p) {
785 log(3, session[s].ip, s, t, "failed to send packet in processipout.\n");
786 return;
787 }
788 tunnelsend(b, len + (p-b), t); // send it...
789 }
790
791 sp->cout += len; // byte count
792 sp->total_cout += len; // byte count
793 sp->pout++;
794 udp_tx += len;
795 sess_count[s].cout += len; // To send to master..
796 }
797
798 //
799 // Helper routine for the TBF filters.
800 // Used to send queued data in to the user!
801 //
802 void send_ipout(sessionidt s, u8 *buf, int len)
803 {
804 sessiont *sp;
805 tunnelidt t;
806 ipt ip;
807
808 u8 b[MAXETHER + 20];
809
810 if (len < 0 || len > MAXETHER) {
811 log(1,0,0,0, "Odd size IP packet: %d bytes\n", len);
812 return;
813 }
814
815 // Skip the tun header
816 buf += 4;
817 len -= 4;
818
819 ip = *(u32 *)(buf + 16);
820
821 if (!session[s].ip)
822 return;
823 t = session[s].tunnel;
824 sp = &session[s];
825
826 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
827
828 // Snooping this session.
829 if (sp->snoop_ip && sp->snoop_port)
830 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
831
832 // Add on L2TP header
833 {
834 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
835 if (!p) {
836 log(3, session[s].ip, s, t, "failed to send packet in send_ipout.\n");
837 return;
838 }
839 tunnelsend(b, len + (p-b), t); // send it...
840 }
841 sp->cout += len; // byte count
842 sp->total_cout += len; // byte count
843 sp->pout++;
844 udp_tx += len;
845 sess_count[s].cout += len; // To send to master..
846 }
847
848 // add an AVP (16 bit)
849 void control16(controlt * c, u16 avp, u16 val, u8 m)
850 {
851 u16 l = (m ? 0x8008 : 0x0008);
852 *(u16 *) (c->buf + c->length + 0) = htons(l);
853 *(u16 *) (c->buf + c->length + 2) = htons(0);
854 *(u16 *) (c->buf + c->length + 4) = htons(avp);
855 *(u16 *) (c->buf + c->length + 6) = htons(val);
856 c->length += 8;
857 }
858
859 // add an AVP (32 bit)
860 void control32(controlt * c, u16 avp, u32 val, u8 m)
861 {
862 u16 l = (m ? 0x800A : 0x000A);
863 *(u16 *) (c->buf + c->length + 0) = htons(l);
864 *(u16 *) (c->buf + c->length + 2) = htons(0);
865 *(u16 *) (c->buf + c->length + 4) = htons(avp);
866 *(u32 *) (c->buf + c->length + 6) = htonl(val);
867 c->length += 10;
868 }
869
870 // add an AVP (32 bit)
871 void controls(controlt * c, u16 avp, char *val, u8 m)
872 {
873 u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
874 *(u16 *) (c->buf + c->length + 0) = htons(l);
875 *(u16 *) (c->buf + c->length + 2) = htons(0);
876 *(u16 *) (c->buf + c->length + 4) = htons(avp);
877 memcpy(c->buf + c->length + 6, val, strlen(val));
878 c->length += 6 + strlen(val);
879 }
880
881 // add a binary AVP
882 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
883 {
884 u16 l = ((m ? 0x8000 : 0) + len + 6);
885 *(u16 *) (c->buf + c->length + 0) = htons(l);
886 *(u16 *) (c->buf + c->length + 2) = htons(0);
887 *(u16 *) (c->buf + c->length + 4) = htons(avp);
888 memcpy(c->buf + c->length + 6, val, len);
889 c->length += 6 + len;
890 }
891
892 // new control connection
893 controlt *controlnew(u16 mtype)
894 {
895 controlt *c;
896 if (!controlfree)
897 c = malloc(sizeof(controlt));
898 else
899 {
900 c = controlfree;
901 controlfree = c->next;
902 }
903 assert(c);
904 c->next = 0;
905 *(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
906 c->length = 12;
907 control16(c, 0, mtype, 1);
908 return c;
909 }
910
911 // send zero block if nothing is waiting
912 // (ZLB send).
913 void controlnull(tunnelidt t)
914 {
915 u8 buf[12];
916 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
917 return;
918
919 *(u16 *) (buf + 0) = htons(0xC802); // flags/ver
920 *(u16 *) (buf + 2) = htons(12); // length
921 *(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
922 *(u16 *) (buf + 6) = htons(0); // session
923 *(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
924 *(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
925 tunnelsend(buf, 12, t);
926 }
927
928 // add a control message to a tunnel, and send if within window
929 void controladd(controlt * c, tunnelidt t, sessionidt s)
930 {
931 *(u16 *) (c->buf + 2) = htons(c->length); // length
932 *(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
933 *(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
934 *(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
935 tunnel[t].ns++; // advance sequence
936 // link in message in to queue
937 if (tunnel[t].controlc)
938 tunnel[t].controle->next = c;
939 else
940 tunnel[t].controls = c;
941 tunnel[t].controle = c;
942 tunnel[t].controlc++;
943 // send now if space in window
944 if (tunnel[t].controlc <= tunnel[t].window)
945 {
946 tunnel[t].try = 0; // first send
947 tunnelsend(c->buf, c->length, t);
948 }
949 }
950
951 //
952 // Throttle or Unthrottle a session
953 //
954 // Throttle the data folling through a session
955 // to be no more than 'throttle' kbit/sec each way.
956 //
957 int throttle_session(sessionidt s, int throttle)
958 {
959 if (!session[s].tunnel)
960 return 0; // No-one home.
961
962 if (!*session[s].user)
963 return 0; // User not logged in
964
965 if (throttle) {
966 if (session[s].tbf_in || session[s].tbf_out) {
967 if (throttle == session[s].throttle)
968 return 1;
969
970 // Currently throttled but the rate is changing.
971
972 free_tbf(session[s].tbf_in);
973 free_tbf(session[s].tbf_out);
974 }
975
976 session[s].tbf_in = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipin);
977 session[s].tbf_out = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipout);
978
979 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
980 session[s].throttle = throttle;
981 cluster_send_session(s);
982 }
983
984 return 1;
985 }
986
987 // else Unthrottling.
988
989 if (!session[s].tbf_in && !session[s].tbf_out && !session[s].throttle)
990 return 0;
991
992 free_tbf(session[s].tbf_in);
993 session[s].tbf_in = 0;
994
995 free_tbf(session[s].tbf_out);
996 session[s].tbf_out = 0;
997
998 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
999 session[s].throttle = throttle;
1000 cluster_send_session(s);
1001 }
1002
1003 return 0;
1004 }
1005
1006 // start tidy shutdown of session
1007 void sessionshutdown(sessionidt s, char *reason)
1008 {
1009 int dead = session[s].die;
1010 int walled_garden = session[s].walled_garden;
1011
1012
1013 CSTAT(call_sessionshutdown);
1014
1015 if (!session[s].tunnel)
1016 {
1017 log(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1018 return; // not a live session
1019 }
1020
1021 if (!dead)
1022 log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1023
1024 session[s].die = now() + 150; // Clean up in 15 seconds
1025
1026 {
1027 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1028 run_plugins(PLUGIN_KILL_SESSION, &data);
1029 }
1030
1031 // RADIUS Stop message
1032 if (session[s].opened && !walled_garden && !dead) {
1033 u16 r = session[s].radius;
1034 if (!r)
1035 {
1036 if (!(r = radiusnew(s)))
1037 {
1038 log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1039 STAT(radius_overflow);
1040 }
1041 else
1042 {
1043 int n;
1044 for (n = 0; n < 15; n++)
1045 radius[r].auth[n] = rand();
1046 }
1047 }
1048 if (r && radius[r].state != RADIUSSTOP)
1049 radiussend(r, RADIUSSTOP); // stop, if not already trying
1050 }
1051
1052 if (session[s].ip)
1053 { // IP allocated, clear and unroute
1054 int r;
1055 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1056 {
1057 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 0);
1058 session[s].route[r].ip = 0;
1059 }
1060
1061 if (session[s].ip_pool_index == -1) // static ip
1062 {
1063 routeset(s, session[s].ip, 0, 0, 0); // Delete route.
1064 session[s].ip = 0;
1065 }
1066 else
1067 free_ip_address(s);
1068
1069 if (session[s].throttle) // Unthrottle if throttled.
1070 throttle_session(s, 0);
1071 }
1072 { // Send CDN
1073 controlt *c = controlnew(14); // sending CDN
1074 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1075 control16(c, 14, s, 1); // assigned session (our end)
1076 controladd(c, session[s].tunnel, s); // send the message
1077 }
1078 cluster_send_session(s);
1079 }
1080
1081 void sendipcp(tunnelidt t, sessionidt s)
1082 {
1083 u8 buf[MAXCONTROL];
1084 u16 r = session[s].radius;
1085 u8 *q;
1086
1087 CSTAT(call_sendipcp);
1088
1089 if (!r)
1090 r = radiusnew(s);
1091
1092 if (radius[r].state != RADIUSIPCP)
1093 {
1094 radius[r].state = RADIUSIPCP;
1095 radius[r].try = 0;
1096 }
1097
1098 radius[r].retry = backoff(radius[r].try++);
1099 if (radius[r].try > 10)
1100 {
1101 radiusclear(r, s); // Clear radius session.
1102 sessionshutdown(s, "No reply on IPCP");
1103 return;
1104 }
1105
1106 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1107 if (!q) {
1108 log(3, session[s].ip, s, t, "failed to send packet in sendipcp.\n");
1109 return;
1110 }
1111
1112 *q = ConfigReq;
1113 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1114 *(u16 *) (q + 2) = htons(10);
1115 q[4] = 3;
1116 q[5] = 6;
1117 *(u32 *) (q + 6) = config->bind_address ? config->bind_address : my_address; // send my IP
1118 tunnelsend(buf, 10 + (q - buf), t); // send it
1119 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1120 }
1121
1122 // kill a session now
1123 void sessionkill(sessionidt s, char *reason)
1124 {
1125
1126 CSTAT(call_sessionkill);
1127
1128 session[s].die = now();
1129 sessionshutdown(s, reason); // close radius/routes, etc.
1130 if (session[s].radius)
1131 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1132
1133 log(2, 0, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1134
1135 throttle_session(s, 0); // Force session to be un-throttle. Free'ing TBF structures.
1136
1137 memset(&session[s], 0, sizeof(session[s]));
1138 session[s].tunnel = T_FREE; // Mark it as free.
1139 session[s].next = sessionfree;
1140 sessionfree = s;
1141 cli_session_actions[s].action = 0;
1142 cluster_send_session(s);
1143 }
1144
1145 // kill a tunnel now
1146 void tunnelkill(tunnelidt t, char *reason)
1147 {
1148 sessionidt s;
1149 controlt *c;
1150
1151 CSTAT(call_tunnelkill);
1152
1153 tunnel[t].state = TUNNELDIE;
1154
1155 // free control messages
1156 while ((c = tunnel[t].controls))
1157 {
1158 controlt * n = c->next;
1159 tunnel[t].controls = n;
1160 tunnel[t].controlc--;
1161 c->next = controlfree;
1162 controlfree = c;
1163 }
1164 // kill sessions
1165 for (s = 1; s < MAXSESSION; s++)
1166 if (session[s].tunnel == t)
1167 sessionkill(s, reason);
1168
1169 // free tunnel
1170 tunnelclear(t);
1171 log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
1172 cli_tunnel_actions[s].action = 0;
1173 cluster_send_tunnel(t);
1174 }
1175
1176 // shut down a tunnel cleanly
1177 void tunnelshutdown(tunnelidt t, char *reason)
1178 {
1179 sessionidt s;
1180
1181 CSTAT(call_tunnelshutdown);
1182
1183 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1184 {
1185 // never set up, can immediately kill
1186 tunnelkill(t, reason);
1187 return;
1188 }
1189 log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1190
1191 // close session
1192 for (s = 1; s < MAXSESSION; s++)
1193 if (session[s].tunnel == t)
1194 sessionkill(s, reason);
1195
1196 tunnel[t].state = TUNNELDIE;
1197 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1198 cluster_send_tunnel(t);
1199 // TBA - should we wait for sessions to stop?
1200 { // Send StopCCN
1201 controlt *c = controlnew(4); // sending StopCCN
1202 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message
1203 control16(c, 9, t, 1); // assigned tunnel (our end)
1204 controladd(c, t, 0); // send the message
1205 }
1206 }
1207
1208 // read and process packet on tunnel (UDP)
1209 void processudp(u8 * buf, int len, struct sockaddr_in *addr)
1210 {
1211 char *chapresponse = NULL;
1212 u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
1213 u8 *p = buf + 2;
1214
1215
1216 CSTAT(call_processudp);
1217
1218 udp_rx += len;
1219 udp_rx_pkt++;
1220 log_hex(5, "UDP Data", buf, len);
1221 STAT(tunnel_rx_packets);
1222 INC_STAT(tunnel_rx_bytes, len);
1223 if (len < 6)
1224 {
1225 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
1226 STAT(tunnel_rx_errors);
1227 return;
1228 }
1229 if ((buf[1] & 0x0F) != 2)
1230 {
1231 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1232 STAT(tunnel_rx_errors);
1233 return;
1234 }
1235 if (*buf & 0x40)
1236 { // length
1237 l = ntohs(*(u16 *) p);
1238 p += 2;
1239 }
1240 t = ntohs(*(u16 *) p);
1241 p += 2;
1242 s = ntohs(*(u16 *) p);
1243 p += 2;
1244 if (s >= MAXSESSION)
1245 {
1246 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
1247 STAT(tunnel_rx_errors);
1248 return;
1249 }
1250 if (t >= MAXTUNNEL)
1251 {
1252 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
1253 STAT(tunnel_rx_errors);
1254 return;
1255 }
1256 if (*buf & 0x08)
1257 { // ns/nr
1258 ns = ntohs(*(u16 *) p);
1259 p += 2;
1260 nr = ntohs(*(u16 *) p);
1261 p += 2;
1262 }
1263 if (*buf & 0x02)
1264 { // offset
1265 u16 o = ntohs(*(u16 *) p);
1266 p += o + 2;
1267 }
1268 if ((p - buf) > l)
1269 {
1270 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
1271 STAT(tunnel_rx_errors);
1272 return;
1273 }
1274 l -= (p - buf);
1275 if (*buf & 0x80)
1276 { // control
1277 u16 message = 0xFFFF; // message type
1278 u8 fatal = 0;
1279 u8 mandatorymessage = 0;
1280 u8 chap = 0; // if CHAP being used
1281 u16 asession = 0; // assigned session
1282 u32 amagic = 0; // magic number
1283 u8 aflags = 0; // flags from last LCF
1284 u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1285 int requestchap = 0; // do we request PAP instead of original CHAP request?
1286 char called[MAXTEL] = ""; // called number
1287 char calling[MAXTEL] = ""; // calling number
1288
1289 if (!config->cluster_iam_master) {
1290 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1291 return;
1292 }
1293
1294 if ((*buf & 0xCA) != 0xC8)
1295 {
1296 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
1297 STAT(tunnel_rx_errors);
1298 return;
1299 }
1300 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",
1301 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1302 // if no tunnel specified, assign one
1303 if (!t)
1304 {
1305 int i;
1306
1307 //
1308 // Is this a duplicate of the first packet? (SCCRQ)
1309 //
1310 for ( i = 1; i <= config->cluster_highest_tunnelid ; ++i) {
1311 if (tunnel[i].state != TUNNELOPENING ||
1312 tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
1313 tunnel[i].port != ntohs(addr->sin_port) )
1314 continue;
1315 t = i;
1316 break;
1317 }
1318 }
1319
1320 if (!t) {
1321 if (!(t = new_tunnel()))
1322 {
1323 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
1324 STAT(tunnel_overflow);
1325 return;
1326 }
1327 tunnelclear(t);
1328 tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
1329 tunnel[t].port = ntohs(addr->sin_port);
1330 tunnel[t].window = 4; // default window
1331 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);
1332 STAT(tunnel_created);
1333 }
1334
1335 // This is used to time out old tunnels
1336 tunnel[t].lastrec = time_now;
1337
1338 // check sequence of this message
1339 {
1340 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1341 // some to clear maybe?
1342 while (tunnel[t].controlc && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1343 {
1344 controlt *c = tunnel[t].controls;
1345 tunnel[t].controls = c->next;
1346 tunnel[t].controlc--;
1347 c->next = controlfree;
1348 controlfree = c;
1349 skip--;
1350 tunnel[t].try = 0; // we have progress
1351 }
1352
1353 // If the 'ns' just received is not the 'nr' we're
1354 // expecting, just send an ack and drop it.
1355 //
1356 // if 'ns' is less, then we got a retransmitted packet.
1357 // if 'ns' is greater than missed a packet. Either way
1358 // we should ignore it.
1359 if (ns != tunnel[t].nr)
1360 {
1361 // is this the sequence we were expecting?
1362 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);
1363 STAT(tunnel_rx_errors);
1364
1365 if (l) // Is this not a ZLB?
1366 controlnull(t);
1367 return;
1368 }
1369 // receiver advance (do here so quoted correctly in any sends below)
1370 if (l) tunnel[t].nr = (ns + 1);
1371 if (skip < 0) skip = 0;
1372 if (skip < tunnel[t].controlc)
1373 {
1374 // some control packets can now be sent that were previous stuck out of window
1375 int tosend = tunnel[t].window - skip;
1376 controlt *c = tunnel[t].controls;
1377 while (c && skip)
1378 {
1379 c = c->next;
1380 skip--;
1381 }
1382 while (c && tosend)
1383 {
1384 tunnel[t].try = 0; // first send
1385 tunnelsend(c->buf, c->length, t);
1386 c = c->next;
1387 tosend--;
1388 }
1389 }
1390 if (!tunnel[t].controlc)
1391 tunnel[t].retry = 0; // caught up
1392 }
1393 if (l)
1394 { // if not a null message
1395 // process AVPs
1396 while (l && !(fatal & 0x80))
1397 {
1398 u16 n = (ntohs(*(u16 *) p) & 0x3FF);
1399 u8 *b = p;
1400 u8 flags = *p;
1401 u16 mtype;
1402 p += n; // next
1403 if (l < n)
1404 {
1405 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
1406 STAT(tunnel_rx_errors);
1407 fatal = flags;
1408 return;
1409 }
1410 l -= n;
1411 if (flags & 0x40)
1412 {
1413 // handle hidden AVPs
1414 if (!*config->l2tpsecret)
1415 {
1416 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
1417 fatal = flags;
1418 continue;
1419 }
1420 if (!session[s].random_vector_length)
1421 {
1422 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
1423 fatal = flags;
1424 continue;
1425 }
1426 log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
1427 }
1428 if (*b & 0x3C)
1429 {
1430 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
1431 fatal = flags;
1432 continue; // next
1433 }
1434 b += 2;
1435 if (*(u16 *) (b))
1436 {
1437 log(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
1438 fatal = flags;
1439 continue; // next
1440 }
1441 b += 2;
1442 mtype = ntohs(*(u16 *) (b));
1443 b += 2;
1444 n -= 6;
1445
1446 log(4, ntohl(addr->sin_addr.s_addr), s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1447 switch (mtype)
1448 {
1449 case 0: // message type
1450 message = ntohs(*(u16 *) b);
1451 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Message type = %d (%s)\n", *b,
1452 l2tp_message_types[message]);
1453 mandatorymessage = flags;
1454 break;
1455 case 1: // result code
1456 {
1457 u16 rescode = ntohs(*(u16 *)(b));
1458 const char* resdesc = "(unknown)";
1459 if (message == 4) { /* StopCCN */
1460 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1461 resdesc = stopccn_result_codes[rescode];
1462 } else if (message == 14) { /* CDN */
1463 if (rescode <= MAX_CDN_RESULT_CODE)
1464 resdesc = cdn_result_codes[rescode];
1465 }
1466
1467 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Result Code %d: %s\n",
1468 rescode, resdesc);
1469 if (n >= 4) {
1470 u16 errcode = ntohs(*(u16 *)(b + 2));
1471 const char* errdesc = "(unknown)";
1472 if (errcode <= MAX_ERROR_CODE)
1473 errdesc = error_codes[errcode];
1474 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error Code %d: %s\n",
1475 errcode, errdesc);
1476 }
1477 if (n > 4)
1478 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error String: %.*s\n",
1479 n-4, b+4);
1480
1481 break;
1482 }
1483 break;
1484 case 2: // protocol version
1485 {
1486 version = ntohs(*(u16 *) (b));
1487 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Protocol version = %d\n", version);
1488 if (version && version != 0x0100)
1489 { // allow 0.0 and 1.0
1490 log(1, ntohl(addr->sin_addr.s_addr), s, t, " Bad protocol version %04X\n",
1491 version);
1492 fatal = flags;
1493 continue; // next
1494 }
1495 }
1496 break;
1497 case 3: // framing capabilities
1498 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
1499 break;
1500 case 4: // bearer capabilities
1501 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
1502 break;
1503 case 5: // tie breaker
1504 // We never open tunnels, so we don't care about tie breakers
1505 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
1506 continue;
1507 case 6: // firmware revision
1508 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
1509 break;
1510 case 7: // host name
1511 memset(tunnel[t].hostname, 0, 128);
1512 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1513 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1514 // TBA - to send to RADIUS
1515 break;
1516 case 8: // vendor name
1517 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1518 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1519 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1520 break;
1521 case 9: // assigned tunnel
1522 tunnel[t].far = ntohs(*(u16 *) (b));
1523 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1524 break;
1525 case 10: // rx window
1526 tunnel[t].window = ntohs(*(u16 *) (b));
1527 if (!tunnel[t].window)
1528 tunnel[t].window = 1; // window of 0 is silly
1529 log(4, ntohl(addr->sin_addr.s_addr), s, t, " rx window = %d\n", tunnel[t].window);
1530 break;
1531 case 11: // Challenge
1532 {
1533 log(4, ntohl(addr->sin_addr.s_addr), s, t, " LAC requested CHAP authentication for tunnel\n");
1534 build_chap_response(b, 2, n, &chapresponse);
1535 }
1536 break;
1537 case 14: // assigned session
1538 asession = session[s].far = ntohs(*(u16 *) (b));
1539 log(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
1540 break;
1541 case 15: // call serial number
1542 log(4, ntohl(addr->sin_addr.s_addr), s, t, " call serial number = %d\n", ntohl(*(u32 *)b));
1543 break;
1544 case 18: // bearer type
1545 log(4, ntohl(addr->sin_addr.s_addr), s, t, " bearer type = %d\n", ntohl(*(u32 *)b));
1546 // TBA - for RADIUS
1547 break;
1548 case 19: // framing type
1549 log(4, ntohl(addr->sin_addr.s_addr), s, t, " framing type = %d\n", ntohl(*(u32 *)b));
1550 // TBA
1551 break;
1552 case 21: // called number
1553 memset(called, 0, MAXTEL);
1554 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1555 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Called <%s>\n", called);
1556 break;
1557 case 22: // calling number
1558 memset(calling, 0, MAXTEL);
1559 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1560 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Calling <%s>\n", calling);
1561 break;
1562 case 23: // subtype
1563 break;
1564 case 24: // tx connect speed
1565 if (n == 4)
1566 {
1567 session[s].tx_connect_speed = ntohl(*(u32 *)b);
1568 }
1569 else
1570 {
1571 // AS5300s send connect speed as a string
1572 char tmp[30] = {0};
1573 memcpy(tmp, b, (n >= 30) ? 30 : n);
1574 session[s].tx_connect_speed = atol(tmp);
1575 }
1576 log(4, ntohl(addr->sin_addr.s_addr), s, t, " TX connect speed <%u>\n",
1577 session[s].tx_connect_speed);
1578 break;
1579 case 38: // rx connect speed
1580 if (n == 4)
1581 {
1582 session[s].rx_connect_speed = ntohl(*(u32 *)b);
1583 }
1584 else
1585 {
1586 // AS5300s send connect speed as a string
1587 char tmp[30] = {0};
1588 memcpy(tmp, b, (n >= 30) ? 30 : n);
1589 session[s].rx_connect_speed = atol(tmp);
1590 }
1591 log(4, ntohl(addr->sin_addr.s_addr), s, t, " RX connect speed <%u>\n",
1592 session[s].rx_connect_speed);
1593 break;
1594 case 25: // Physical Channel ID
1595 {
1596 u32 tmp = ntohl(*(u32 *)b);
1597 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Physical Channel ID <%X>\n", tmp);
1598 break;
1599 }
1600 case 29: // Proxy Authentication Type
1601 {
1602 u16 authtype = ntohs(*(u16 *)b);
1603 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Type %d (%s)\n",
1604 authtype, authtypes[authtype]);
1605 requestchap = (authtype == 2);
1606 break;
1607 }
1608 case 30: // Proxy Authentication Name
1609 {
1610 char authname[64] = {0};
1611 memcpy(authname, b, (n > 63) ? 63 : n);
1612 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Name (%s)\n",
1613 authname);
1614 break;
1615 }
1616 case 31: // Proxy Authentication Challenge
1617 {
1618 memcpy(radius[session[s].radius].auth, b, 16);
1619 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Challenge\n");
1620 break;
1621 }
1622 case 32: // Proxy Authentication ID
1623 {
1624 u16 authid = ntohs(*(u16 *)(b));
1625 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth ID (%d)\n",
1626 authid);
1627 if (session[s].radius)
1628 radius[session[s].radius].id = authid;
1629 break;
1630 }
1631 case 33: // Proxy Authentication Response
1632 {
1633 char authresp[64] = {0};
1634 memcpy(authresp, b, (n > 63) ? 63 : n);
1635 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Response\n");
1636 break;
1637 }
1638 case 27: // last send lcp
1639 { // find magic number
1640 u8 *p = b, *e = p + n;
1641 while (p < e && p[1])
1642 {
1643 if (*p == 5 && p[1] == 6)
1644 amagic = ntohl(*(u32 *) (p + 2));
1645 else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5)
1646 chap = 1;
1647 else if (*p == 7)
1648 aflags |= SESSIONPFC;
1649 else if (*p == 8)
1650 aflags |= SESSIONACFC;
1651 p += p[1];
1652 }
1653
1654 {
1655 char tmp[500] = {0};
1656 tmp[0] = ConfigReq;
1657 memcpy((tmp + 1), b, n);
1658 }
1659 }
1660 break;
1661 case 28: // last recv lcp confreq
1662 {
1663 char tmp[500] = {0};
1664 tmp[0] = ConfigReq;
1665 memcpy((tmp + 1), b, n);
1666 break;
1667 }
1668 case 26: // Initial Received LCP CONFREQ
1669 {
1670 char tmp[500] = {0};
1671 tmp[0] = ConfigReq;
1672 memcpy((tmp + 1), b, n);
1673 }
1674 break;
1675 case 39: // seq required - we control it as an LNS anyway...
1676 break;
1677 case 36: // Random Vector
1678 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Random Vector received. Enabled AVP Hiding.\n");
1679 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1680 memcpy(session[s].random_vector, b, n);
1681 session[s].random_vector_length = n;
1682 break;
1683 default:
1684 log(2, ntohl(addr->sin_addr.s_addr), s, t, " Unknown AVP type %d\n", mtype);
1685 fatal = flags;
1686 continue; // next
1687 }
1688 }
1689 // process message
1690 if (fatal & 0x80)
1691 tunnelshutdown(t, "Unknown Mandatory AVP");
1692 else
1693 switch (message)
1694 {
1695 case 1: // SCCRQ - Start Control Connection Request
1696 {
1697 controlt *c = controlnew(2); // sending SCCRP
1698 control16(c, 2, version, 1); // protocol version
1699 control32(c, 3, 3, 1); // framing
1700 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1701 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1702 control16(c, 9, t, 1); // assigned tunnel
1703 controladd(c, t, s); // send the resply
1704 }
1705 tunnel[t].state = TUNNELOPENING;
1706 break;
1707 case 2: // SCCRP
1708 tunnel[t].state = TUNNELOPEN;
1709 break;
1710 case 3: // SCCN
1711 tunnel[t].state = TUNNELOPEN;
1712 controlnull(t); // ack
1713 break;
1714 case 4: // StopCCN
1715 controlnull(t); // ack
1716 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1717 tunnelkill(t, "Stopped"); // Immediately force everything dead
1718 break;
1719 case 6: // HELLO
1720 controlnull(t); // simply ACK
1721 break;
1722 case 7: // OCRQ
1723 // TBA
1724 break;
1725 case 8: // OCRO
1726 // TBA
1727 break;
1728 case 9: // OCCN
1729 // TBA
1730 break;
1731 case 10: // ICRQ
1732 if (!sessionfree)
1733 {
1734 STAT(session_overflow);
1735 tunnelshutdown(t, "No free sessions");
1736 }
1737 else
1738 {
1739 u16 r;
1740 controlt *c;
1741
1742 s = sessionfree;
1743 sessionfree = session[s].next;
1744 memset(&session[s], 0, sizeof(session[s]));
1745
1746 if (s > config->cluster_highest_sessionid)
1747 config->cluster_highest_sessionid = s;
1748
1749 // make a RADIUS session
1750 if (!(r = radiusnew(s)))
1751 {
1752 log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
1753 sessionkill(s, "no free RADIUS sesions");
1754 return;
1755 }
1756
1757 c = controlnew(11); // sending ICRP
1758 session[s].id = sessionid++;
1759 session[s].opened = time(NULL);
1760 session[s].tunnel = t;
1761 session[s].far = asession;
1762 session[s].last_packet = time_now;
1763 log(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1764 control16(c, 14, s, 1); // assigned session
1765 controladd(c, t, s); // send the reply
1766 {
1767 // Generate a random challenge
1768 int n;
1769 for (n = 0; n < 15; n++)
1770 radius[r].auth[n] = rand();
1771 }
1772 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1773 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1774 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1775 STAT(session_created);
1776 }
1777 break;
1778 case 11: // ICRP
1779 // TBA
1780 break;
1781 case 12: // ICCN
1782 session[s].magic = amagic; // set magic number
1783 session[s].l2tp_flags = aflags; // set flags received
1784 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
1785 controlnull(t); // ack
1786 // In CHAP state, request PAP instead
1787 if (requestchap)
1788 initlcp(t, s);
1789 break;
1790 case 14: // CDN
1791 controlnull(t); // ack
1792 sessionshutdown(s, "Closed (Received CDN)");
1793 break;
1794 case 0xFFFF:
1795 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
1796 break;
1797 default:
1798 STAT(tunnel_rx_errors);
1799 if (mandatorymessage & 0x80)
1800 tunnelshutdown(t, "Unknown message");
1801 else
1802 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
1803 break;
1804 }
1805 if (chapresponse) free(chapresponse);
1806 cluster_send_tunnel(t);
1807 }
1808 else
1809 {
1810 log(4, 0, s, t, " Got a ZLB ack\n");
1811 }
1812 }
1813 else
1814 { // data
1815 u16 prot;
1816
1817 log_hex(5, "Receive Tunnel Data", p, l);
1818 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1819 { // HDLC address header, discard
1820 p += 2;
1821 l -= 2;
1822 }
1823 if (l < 2)
1824 {
1825 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
1826 STAT(tunnel_rx_errors);
1827 return;
1828 }
1829 if (*p & 1)
1830 {
1831 prot = *p++;
1832 l--;
1833 }
1834 else
1835 {
1836 prot = ntohs(*(u16 *) p);
1837 p += 2;
1838 l -= 2;
1839 }
1840
1841 if (s && !session[s].tunnel) // Is something wrong??
1842 {
1843 if (!config->cluster_iam_master)
1844 {
1845 // Pass it off to the master to deal with..
1846 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1847 return;
1848 }
1849
1850
1851 log(1, ntohl(addr->sin_addr.s_addr), s, t, "UDP packet contains session %d "
1852 "but no session[%d].tunnel exists (LAC said"
1853 " tunnel = %d). Dropping packet.\n", s, s, t);
1854 STAT(tunnel_rx_errors);
1855 return;
1856 }
1857
1858 if (session[s].die)
1859 {
1860 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
1861 // I'm pretty sure this isn't right -- mo.
1862 // return; // closing session, PPP not processed
1863 }
1864 if (prot == PPPPAP)
1865 {
1866 session[s].last_packet = time_now;
1867 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1868 processpap(t, s, p, l);
1869 }
1870 else if (prot == PPPCHAP)
1871 {
1872 session[s].last_packet = time_now;
1873 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1874 processchap(t, s, p, l);
1875 }
1876 else if (prot == PPPLCP)
1877 {
1878 session[s].last_packet = time_now;
1879 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1880 processlcp(t, s, p, l);
1881 }
1882 else if (prot == PPPIPCP)
1883 {
1884 session[s].last_packet = time_now;
1885 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1886 processipcp(t, s, p, l);
1887 }
1888 else if (prot == PPPCCP)
1889 {
1890 session[s].last_packet = time_now;
1891 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1892 processccp(t, s, p, l);
1893 }
1894 else if (prot == PPPIP)
1895 {
1896 if (!config->cluster_iam_master)
1897 {
1898 // We're a slave. Should we forward this packet to the master?
1899
1900 // Is this a walled garden session, or something that needs it's
1901 // idle time updated??
1902
1903 // Maintain the idle timeouts on the master. If this would
1904 // significantly reset the idletimeout, run it via the master
1905 // to refresh the master's idle timer.
1906 // Not sure this is ideal: It may re-order packets.
1907
1908 if (session[s].walled_garden || (session[s].last_packet + (ECHO_TIMEOUT/2)) < time_now)
1909 {
1910 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1911 session[s].last_packet = time_now;
1912 return;
1913 }
1914 // fall through to processipin.
1915 } else
1916 session[s].last_packet = time_now;
1917 processipin(t, s, p, l);
1918 }
1919 else
1920 {
1921 STAT(tunnel_rx_errors);
1922 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
1923 }
1924 }
1925 }
1926
1927 // read and process packet on tun
1928 void processtun(u8 * buf, int len)
1929 {
1930 log_hex(5, "Receive TUN Data", buf, len);
1931 STAT(tun_rx_packets);
1932 INC_STAT(tun_rx_bytes, len);
1933
1934 CSTAT(call_processtun);
1935
1936 eth_rx_pkt++;
1937 eth_rx += len;
1938 if (len < 22)
1939 {
1940 log(1, 0, 0, 0, "Short tun packet %d bytes\n", len);
1941 STAT(tun_rx_errors);
1942 return;
1943 }
1944
1945 if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
1946 processipout(buf, len);
1947 // Else discard.
1948 }
1949
1950 //
1951 // Maximum number of actions to complete.
1952 // This is to avoid sending out too many packets
1953 // at once.
1954 #define MAX_ACTIONS 500
1955
1956 int regular_cleanups(void)
1957 {
1958 static sessionidt s = 0; // Next session to check for actions on.
1959 tunnelidt t;
1960 int count=0,i;
1961 u16 r;
1962 static clockt next_acct = 0;
1963 int a;
1964
1965 log(3, 0, 0, 0, "Begin regular cleanup\n");
1966
1967 for (r = 1; r < MAXRADIUS; r++)
1968 {
1969 if (!radius[r].state)
1970 continue;
1971 if (radius[r].retry)
1972 {
1973 if (radius[r].retry <= TIME)
1974 radiusretry(r);
1975 } else
1976 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
1977 }
1978 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
1979 {
1980 // check for expired tunnels
1981 if (tunnel[t].die && tunnel[t].die <= TIME)
1982 {
1983 STAT(tunnel_timeout);
1984 tunnelkill(t, "Expired");
1985 continue;
1986 }
1987 // check for message resend
1988 if (tunnel[t].retry && tunnel[t].controlc)
1989 {
1990 // resend pending messages as timeout on reply
1991 if (tunnel[t].retry <= TIME)
1992 {
1993 controlt *c = tunnel[t].controls;
1994 u8 w = tunnel[t].window;
1995 tunnel[t].try++; // another try
1996 if (tunnel[t].try > 5)
1997 tunnelkill(t, "Timeout on control message"); // game over
1998 else
1999 while (c && w--)
2000 {
2001 tunnelsend(c->buf, c->length, t);
2002 c = c->next;
2003 }
2004 }
2005 }
2006 // Send hello
2007 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2008 {
2009 controlt *c = controlnew(6); // sending HELLO
2010 controladd(c, t, 0); // send the message
2011 log(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
2012 }
2013
2014 // Check for tunnel changes requested from the CLI
2015 if ((a = cli_tunnel_actions[t].action))
2016 {
2017 cli_tunnel_actions[t].action = 0;
2018 if (a & CLI_TUN_KILL)
2019 {
2020 log(2, tunnel[t].ip, 0, t, "Dropping tunnel by CLI\n");
2021 tunnelshutdown(t, "Requested by administrator");
2022 }
2023 }
2024
2025 }
2026
2027 count = 0;
2028 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2029 {
2030 s++;
2031 if (s > config->cluster_highest_sessionid)
2032 s = 1;
2033
2034 if (!session[s].tunnel) // Session isn't in use
2035 continue;
2036
2037 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED) )
2038 {
2039 // IPCP has not completed yet. Resend
2040 log(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2041 sendipcp(session[s].tunnel, s);
2042 }
2043
2044 // check for expired sessions
2045 if (session[s].die && session[s].die <= TIME)
2046 {
2047 sessionkill(s, "Expired");
2048 if (++count >= MAX_ACTIONS) break;
2049 continue;
2050 }
2051
2052 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2053 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2054 {
2055 sessionkill(s, "No response to LCP ECHO requests");
2056 STAT(session_timeout);
2057 if (++count >= MAX_ACTIONS) break;
2058 continue;
2059 }
2060
2061 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2062 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2063 {
2064 u8 b[MAXCONTROL] = {0};
2065
2066 u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2067 if (!q) {
2068 log(3, session[s].ip, s, t, "failed to send ECHO packet.\n");
2069 continue;
2070 }
2071
2072 *q = EchoReq;
2073 *(u8 *)(q + 1) = (time_now % 255); // ID
2074 *(u16 *)(q + 2) = htons(8); // Length
2075 *(u32 *)(q + 4) = 0; // Magic Number (not supported)
2076
2077 log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2078 (int)(time_now - session[s].last_packet));
2079 tunnelsend(b, 24, session[s].tunnel); // send it
2080 if (++count >= MAX_ACTIONS) break;
2081 continue;
2082 }
2083
2084 // Check for actions requested from the CLI
2085 if ((a = cli_session_actions[s].action))
2086 {
2087 int send = 0;
2088
2089 cli_session_actions[s].action = 0;
2090 if (a & CLI_SESS_KILL)
2091 {
2092 log(2, 0, s, session[s].tunnel, "Dropping session by CLI\n");
2093 sessionshutdown(s, "Requested by administrator");
2094 a = 0; // dead, no need to check for other actions
2095 }
2096
2097 if (a & CLI_SESS_SNOOP)
2098 {
2099 log(2, 0, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2100 inet_toa(cli_session_actions[s].snoop_ip), cli_session_actions[s].snoop_port);
2101
2102 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2103 session[s].snoop_port = cli_session_actions[s].snoop_port;
2104 send++;
2105 }
2106
2107 if (a & CLI_SESS_NOSNOOP)
2108 {
2109 log(2, 0, s, session[s].tunnel, "Unsnooping session by CLI\n");
2110 session[s].snoop_ip = 0;
2111 session[s].snoop_port = 0;
2112 send++;
2113 }
2114
2115 if (a & CLI_SESS_THROTTLE)
2116 {
2117 log(2, 0, s, session[s].tunnel, "Throttling session by CLI (to %d)\n",
2118 cli_session_actions[s].throttle);
2119
2120 throttle_session(s, cli_session_actions[s].throttle);
2121 }
2122
2123 if (a & CLI_SESS_NOTHROTTLE)
2124 {
2125 log(2, 0, s, session[s].tunnel, "Un-throttling session by CLI\n");
2126 throttle_session(s, 0);
2127 }
2128
2129 if (send)
2130 cluster_send_session(s);
2131
2132 if (++count >= MAX_ACTIONS) break;
2133 continue;
2134 }
2135 }
2136
2137 if (config->accounting_dir && next_acct <= TIME)
2138 {
2139 // Dump accounting data
2140 next_acct = TIME + ACCT_TIME;
2141 dump_acct_info();
2142 }
2143
2144 if (count >= MAX_ACTIONS)
2145 return 1; // Didn't finish!
2146
2147 log(3, 0, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2148 return 0;
2149 }
2150
2151
2152 //
2153 // Are we in the middle of a tunnel update, or radius
2154 // requests??
2155 //
2156 int still_busy(void)
2157 {
2158 int i;
2159 static int last_talked = 0;
2160 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i) {
2161 if (!tunnel[i].controlc)
2162 continue;
2163
2164 if (last_talked != TIME) {
2165 log(2,0,0,0, "Tunnel %d still has un-acked control messages.\n", i);
2166 last_talked = TIME;
2167 }
2168 return 1;
2169 }
2170
2171 for (i = 1; i < MAXRADIUS; i++)
2172 {
2173 if (radius[i].state == RADIUSNULL)
2174 continue;
2175 if (radius[i].state == RADIUSWAIT)
2176 continue;
2177
2178 if (last_talked != TIME) {
2179 log(2,0,0,0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2180 last_talked = TIME;
2181 }
2182 return 1;
2183 }
2184
2185 return 0;
2186 }
2187
2188 // main loop - gets packets on tun or udp and processes them
2189 void mainloop(void)
2190 {
2191 fd_set cr;
2192 int cn, i;
2193 u8 buf[65536];
2194 struct timeval to;
2195 clockt next_cluster_ping = 0; // send initial ping immediately
2196 time_t next_clean = time_now + config->cleanup_interval;
2197
2198 log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2199 udpfd, tunfd, cluster_sockfd, controlfd);
2200
2201 FD_ZERO(&cr);
2202 FD_SET(udpfd, &cr);
2203 FD_SET(tunfd, &cr);
2204 FD_SET(controlfd, &cr);
2205 FD_SET(clifd, &cr);
2206 if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
2207 cn = udpfd;
2208 if (cn < tunfd) cn = tunfd;
2209 if (cn < controlfd) cn = controlfd;
2210 if (cn < clifd) cn = clifd;
2211 if (cn < cluster_sockfd) cn = cluster_sockfd;
2212 for (i = 0; i < config->num_radfds; i++)
2213 {
2214 if (!radfds[i]) continue;
2215 FD_SET(radfds[i], &cr);
2216 if (radfds[i] > cn)
2217 cn = radfds[i];
2218 }
2219
2220 while (!main_quit || still_busy())
2221 {
2222 fd_set r;
2223 int n = cn;
2224 #ifdef BGP
2225 fd_set w;
2226 int bgp_set[BGP_NUM_PEERS];
2227 #endif /* BGP */
2228
2229 if (config->reload_config)
2230 {
2231 // Update the config state based on config settings
2232 update_config();
2233 }
2234
2235 memcpy(&r, &cr, sizeof(fd_set));
2236 to.tv_sec = 0;
2237 to.tv_usec = 100000; // 1/10th of a second.
2238
2239 #ifdef BGP
2240 FD_ZERO(&w);
2241 for (i = 0; i < BGP_NUM_PEERS; i++)
2242 {
2243 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2244 if (bgp_set[i] & 1)
2245 {
2246 FD_SET(bgp_peers[i].sock, &r);
2247 if (bgp_peers[i].sock > n)
2248 n = bgp_peers[i].sock;
2249 }
2250
2251 if (bgp_set[i] & 2)
2252 {
2253 FD_SET(bgp_peers[i].sock, &w);
2254 if (bgp_peers[i].sock > n)
2255 n = bgp_peers[i].sock;
2256 }
2257 }
2258
2259 n = select(n + 1, &r, &w, 0, &to);
2260 #else /* BGP */
2261 n = select(n + 1, &r, 0, 0, &to);
2262 #endif /* BGP */
2263
2264 TIME = now();
2265 if (n < 0)
2266 {
2267 if (errno == EINTR)
2268 continue;
2269
2270 log(0, 0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2271 main_quit++;
2272 break;
2273 }
2274 else if (n)
2275 {
2276 struct sockaddr_in addr;
2277 int alen = sizeof(addr);
2278 if (FD_ISSET(udpfd, &r))
2279 {
2280 int c, n;
2281 for (c = 0; c < config->multi_read_count; c++)
2282 {
2283 if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2284 processudp(buf, n, &addr);
2285 else
2286 break;
2287 }
2288 }
2289 if (FD_ISSET(tunfd, &r))
2290 {
2291 int c, n;
2292 for (c = 0; c < config->multi_read_count; c++)
2293 {
2294 if ((n = read(tunfd, buf, sizeof(buf))) > 0)
2295 processtun(buf, n);
2296 else
2297 break;
2298 }
2299 }
2300 for (i = 0; i < config->num_radfds; i++)
2301 if (FD_ISSET(radfds[i], &r))
2302 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2303 if (FD_ISSET(cluster_sockfd, &r)) {
2304 int size;
2305 size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
2306 processcluster(buf, size, addr.sin_addr.s_addr);
2307 }
2308 if (FD_ISSET(controlfd, &r))
2309 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
2310 if (FD_ISSET(clifd, &r))
2311 {
2312 struct sockaddr_in addr;
2313 int sockfd;
2314 int len = sizeof(addr);
2315
2316 if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
2317 {
2318 log(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
2319 continue;
2320 }
2321 else
2322 {
2323 cli_do(sockfd);
2324 close(sockfd);
2325 }
2326 }
2327 }
2328
2329 // Runs on every machine (master and slaves).
2330 if (cluster_sockfd && next_cluster_ping <= TIME)
2331 {
2332 // Check to see which of the cluster is still alive..
2333
2334 cluster_send_ping(basetime); // Only does anything if we're a slave
2335 cluster_check_master(); // ditto.
2336
2337 cluster_heartbeat(); // Only does anything if we're a master.
2338 cluster_check_slaves(); // ditto.
2339
2340 master_update_counts(); // If we're a slave, send our byte counters to our master.
2341
2342 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2343 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2344 else
2345 next_cluster_ping = TIME + config->cluster_hb_interval;
2346 }
2347
2348 // Run token bucket filtering queue..
2349 // Only run it every 1/10th of a second.
2350 // Runs on all machines both master and slave.
2351 {
2352 static clockt last_run = 0;
2353 if (last_run != TIME) {
2354 last_run = TIME;
2355 tbf_run_timer();
2356 }
2357 }
2358
2359 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2360 * something to read, else under load this will never actually run....
2361 *
2362 */
2363 if (config->cluster_iam_master && next_clean <= time_now) {
2364 if (regular_cleanups()) { // Did it finish?
2365 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2366 } else {
2367 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2368 }
2369 }
2370
2371 #ifdef BGP
2372 for (i = 0; i < BGP_NUM_PEERS; i++)
2373 {
2374 bgp_process(&bgp_peers[i],
2375 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
2376 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
2377 }
2378 #endif /* BGP */
2379 }
2380
2381 // Are we the master and shutting down??
2382 if (config->cluster_iam_master)
2383 cluster_heartbeat(); // Flush any queued changes..
2384
2385 // Ok. Notify everyone we're shutting down. If we're
2386 // the master, this will force an election.
2387 cluster_send_ping(0);
2388
2389 //
2390 // Important!!! We MUST not process any packets past this point!
2391 }
2392
2393 // Init data structures
2394 void initdata(void)
2395 {
2396 int i;
2397
2398 _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2399 if (_statistics == MAP_FAILED)
2400 {
2401 log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
2402 exit(1);
2403 }
2404 config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2405 if (config == MAP_FAILED)
2406 {
2407 log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
2408 exit(1);
2409 }
2410 memset(config, 0, sizeof(struct configt));
2411 time(&config->start_time);
2412 strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
2413 tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2414 if (tunnel == MAP_FAILED)
2415 {
2416 log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
2417 exit(1);
2418 }
2419 session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2420 if (session == MAP_FAILED)
2421 {
2422 log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
2423 exit(1);
2424 }
2425
2426 sess_count = mmap(NULL, sizeof(sessioncountt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2427 if (sess_count == MAP_FAILED)
2428 {
2429 log(0, 0, 0, 0, "Error doing mmap for sessions_count: %s\n", strerror(errno));
2430 exit(1);
2431 }
2432
2433 radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2434 if (radius == MAP_FAILED)
2435 {
2436 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2437 exit(1);
2438 }
2439 ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2440 if (ip_address_pool == MAP_FAILED)
2441 {
2442 log(0, 0, 0, 0, "Error doing mmap for ip_address_pool: %s\n", strerror(errno));
2443 exit(1);
2444 }
2445 #ifdef RINGBUFFER
2446 ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2447 if (ringbuffer == MAP_FAILED)
2448 {
2449 log(0, 0, 0, 0, "Error doing mmap for ringbuffer: %s\n", strerror(errno));
2450 exit(1);
2451 }
2452 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2453 #endif
2454
2455 cli_session_actions = mmap(NULL, sizeof(struct cli_session_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2456 if (cli_session_actions == MAP_FAILED)
2457 {
2458 log(0, 0, 0, 0, "Error doing mmap for cli session actions: %s\n", strerror(errno));
2459 exit(1);
2460 }
2461 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2462 cli_tunnel_actions = mmap(NULL, sizeof(struct cli_tunnel_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2463 if (cli_tunnel_actions == MAP_FAILED)
2464 {
2465 log(0, 0, 0, 0, "Error doing mmap for cli tunnel actions: %s\n", strerror(errno));
2466 exit(1);
2467 }
2468 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2469
2470 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2471 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2472 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2473 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2474
2475 // Put all the sessions on the free list marked as undefined.
2476 for (i = 1; i < MAXSESSION - 1; i++) {
2477 session[i].next = i + 1;
2478 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2479 }
2480 session[MAXSESSION - 1].next = 0;
2481 sessionfree = 1;
2482
2483 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2484 for (i = 1; i < MAXTUNNEL- 1; i++) {
2485 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2486 }
2487
2488 if (!*hostname)
2489 {
2490 char *p;
2491 // Grab my hostname unless it's been specified
2492 gethostname(hostname, sizeof(hostname));
2493 if ((p = strchr(hostname, '.'))) *p = 0;
2494 }
2495 _statistics->start_time = _statistics->last_reset = time(NULL);
2496
2497 #ifdef BGP
2498 bgp_peers = mmap(NULL, sizeof(struct bgp_peer) * BGP_NUM_PEERS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2499 if (bgp_peers == MAP_FAILED)
2500 {
2501 log(0, 0, 0, 0, "Error doing mmap for bgp: %s\n", strerror(errno));
2502 exit(1);
2503 }
2504 #endif /* BGP */
2505 }
2506
2507 void initiptables(void)
2508 {
2509 /* Flush the tables here so that we have a clean slate */
2510
2511 // Not needed. 'nat' is setup by garden.c
2512 // mangle isn't used (as throttling is done by tbf inhouse).
2513 }
2514
2515 int assign_ip_address(sessionidt s)
2516 {
2517 u32 i;
2518 int best = -1;
2519 time_t best_time = time_now;
2520 char *u = session[s].user;
2521 char reuse = 0;
2522
2523
2524 CSTAT(call_assign_ip_address);
2525
2526 for (i = 1; i < ip_pool_size; i++)
2527 {
2528 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2529 continue;
2530
2531 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2532 {
2533 best = i;
2534 reuse = 1;
2535 break;
2536 }
2537
2538 if (ip_address_pool[i].last < best_time)
2539 {
2540 best = i;
2541 if (!(best_time = ip_address_pool[i].last))
2542 break; // never used, grab this one
2543 }
2544 }
2545
2546 if (best < 0)
2547 {
2548 log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2549 return 0;
2550 }
2551
2552 session[s].ip = ip_address_pool[best].address;
2553 session[s].ip_pool_index = best;
2554 ip_address_pool[best].assigned = 1;
2555 ip_address_pool[best].last = time_now;
2556 ip_address_pool[best].session = s;
2557 if (session[s].walled_garden)
2558 /* Don't track addresses of users in walled garden (note: this
2559 means that their address isn't "sticky" even if they get
2560 un-gardened). */
2561 ip_address_pool[best].user[0] = 0;
2562 else
2563 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2564
2565 STAT(ip_allocated);
2566 log(4, ip_address_pool[best].address, s, session[s].tunnel,
2567 "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
2568
2569 return 1;
2570 }
2571
2572 void free_ip_address(sessionidt s)
2573 {
2574 int i = session[s].ip_pool_index;
2575
2576 if (!session[s].ip)
2577 return; // what the?
2578
2579 if (i < 0) // Is this actually part of the ip pool?
2580 i = 0;
2581
2582 STAT(ip_freed);
2583 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2584 session[s].ip = 0;
2585 ip_address_pool[i].assigned = 0;
2586 ip_address_pool[i].session = 0;
2587 ip_address_pool[i].last = time_now;
2588
2589
2590 CSTAT(call_free_ip_address);
2591
2592 }
2593
2594 //
2595 // Fsck the address pool against the session table.
2596 // Normally only called when we become a master.
2597 //
2598 // This isn't perfect: We aren't keep tracking of which
2599 // users used to have an IP address.
2600 //
2601 void rebuild_address_pool(void)
2602 {
2603 int i;
2604
2605 //
2606 // Zero the IP pool allocation, and build
2607 // a map from IP address to pool index.
2608 for (i = 1; i < MAXIPPOOL; ++i) {
2609 ip_address_pool[i].assigned = 0;
2610 ip_address_pool[i].session = 0;
2611 if (!ip_address_pool[i].address)
2612 continue;
2613
2614 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2615 }
2616
2617 for (i = 0; i < MAXSESSION; ++i) {
2618 int ipid;
2619 if (!session[i].ip || !session[i].tunnel)
2620 continue;
2621 ipid = - lookup_ipmap(htonl(session[i].ip));
2622
2623 if (session[i].ip_pool_index < 0) { // Not allocated out of the pool.
2624 if (ipid < 1) // Not found in the pool either? good.
2625 continue;
2626
2627 log(0, 0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2628 i, inet_toa(session[i].ip), ipid);
2629
2630 // Fall through and process it as part of the pool.
2631 }
2632
2633
2634 if (ipid > MAXIPPOOL || ipid < 0) {
2635 log(0, 0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2636 ipid = -1;
2637 session[i].ip_pool_index = ipid;
2638 continue;
2639 }
2640
2641 ip_address_pool[ipid].assigned = 1;
2642 ip_address_pool[ipid].session = i;
2643 ip_address_pool[ipid].last = time_now;
2644 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2645 session[i].ip_pool_index = ipid;
2646 cache_ipmap(session[i].ip, i); // Fix the ip map.
2647 }
2648 }
2649
2650 //
2651 // Fix the address pool to match a changed session.
2652 // (usually when the master sends us an update).
2653 void fix_address_pool(int sid)
2654 {
2655 int ipid;
2656
2657 ipid = session[sid].ip_pool_index;
2658
2659 if (ipid > ip_pool_size)
2660 return; // Ignore it. rebuild_address_pool will fix it up.
2661
2662 if (ip_address_pool[ipid].address != session[sid].ip)
2663 return; // Just ignore it. rebuild_address_pool will take care of it.
2664
2665 ip_address_pool[ipid].assigned = 1;
2666 ip_address_pool[ipid].session = sid;
2667 ip_address_pool[ipid].last = time_now;
2668 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2669 }
2670
2671 //
2672 // Add a block of addresses to the IP pool to hand out.
2673 //
2674 void add_to_ip_pool(u32 addr, u32 mask)
2675 {
2676 int i;
2677 if (mask == 0)
2678 mask = 0xffffffff; // Host route only.
2679
2680 addr &= mask;
2681
2682 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2683 return ;
2684
2685 for (i = addr ;(i & mask) == addr; ++i)
2686 {
2687 if ((i & 0xff) == 0 || (i&0xff) == 255)
2688 continue; // Skip 0 and broadcast addresses.
2689
2690 ip_address_pool[ip_pool_size].address = i;
2691 ip_address_pool[ip_pool_size].assigned = 0;
2692 ++ip_pool_size;
2693 if (ip_pool_size >= MAXIPPOOL)
2694 {
2695 log(0,0,0,0, "Overflowed IP pool adding %s\n", inet_toa(htonl(addr)) );
2696 return;
2697 }
2698 }
2699 }
2700
2701 // Initialize the IP address pool
2702 void initippool()
2703 {
2704 FILE *f;
2705 char *p;
2706 char buf[4096];
2707 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2708
2709 if (!(f = fopen(IPPOOLFILE, "r")))
2710 {
2711 log(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2712 exit(1);
2713 }
2714
2715 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2716 {
2717 char *pool = buf;
2718 buf[4095] = 0; // Force it to be zero terminated/
2719
2720 if (*buf == '#' || *buf == '\n')
2721 continue; // Skip comments / blank lines
2722 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2723 if ((p = (char *)strchr(buf, ':')))
2724 {
2725 ipt src;
2726 *p = '\0';
2727 src = inet_addr(buf);
2728 if (src == INADDR_NONE)
2729 {
2730 log(0, 0, 0, 0, "Invalid address pool IP %s\n", buf);
2731 exit(1);
2732 }
2733 // This entry is for a specific IP only
2734 if (src != config->bind_address)
2735 continue;
2736 *p = ':';
2737 pool = p+1;
2738 }
2739 if ((p = (char *)strchr(pool, '/')))
2740 {
2741 // It's a range
2742 int numbits = 0;
2743 u32 start = 0, mask = 0;
2744
2745 log(2, 0, 0, 0, "Adding IP address range %s\n", buf);
2746 *p++ = 0;
2747 if (!*p || !(numbits = atoi(p)))
2748 {
2749 log(0, 0, 0, 0, "Invalid pool range %s\n", buf);
2750 continue;
2751 }
2752 start = ntohl(inet_addr(pool));
2753 mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
2754
2755 // Add a static route for this pool
2756 log(5, 0, 0, 0, "Adding route for address pool %s/%u\n", inet_toa(htonl(start)), 32 + mask);
2757 routeset(0, start, mask, 0, 1);
2758
2759 add_to_ip_pool(start, mask);
2760 }
2761 else
2762 {
2763 // It's a single ip address
2764 add_to_ip_pool(inet_addr(pool), 0);
2765 }
2766 }
2767 fclose(f);
2768 log(1, 0, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2769 }
2770
2771 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
2772 {
2773 struct sockaddr_in snoop_addr = {0};
2774 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2775 return;
2776
2777 snoop_addr.sin_family = AF_INET;
2778 snoop_addr.sin_addr.s_addr = destination;
2779 snoop_addr.sin_port = ntohs(port);
2780
2781 log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
2782 packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
2783 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
2784 log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
2785 STAT(packets_snooped);
2786 }
2787
2788 void dump_acct_info()
2789 {
2790 char filename[1024];
2791 char timestr[64];
2792 time_t t = time(NULL);
2793 int i;
2794 FILE *f = NULL;
2795
2796
2797 CSTAT(call_dump_acct_info);
2798
2799 strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
2800 snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
2801
2802 for (i = 0; i < MAXSESSION; i++)
2803 {
2804 if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
2805 continue;
2806 if (!f)
2807 {
2808 time_t now = time(NULL);
2809 if (!(f = fopen(filename, "w")))
2810 {
2811 log(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
2812 return;
2813 }
2814 log(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
2815 fprintf(f, "# dslwatch.pl dump file V1.01\n"
2816 "# host: %s\n"
2817 "# time: %ld\n"
2818 "# uptime: %ld\n"
2819 "# format: username ip qos uptxoctets downrxoctets\n",
2820 hostname,
2821 now,
2822 now - basetime);
2823 }
2824
2825 log(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
2826 fprintf(f, "%s %s %d %u %u\n",
2827 session[i].user, // username
2828 inet_toa(htonl(session[i].ip)), // ip
2829 (session[i].throttle) ? 2 : 1, // qos
2830 (u32)session[i].cin, // uptxoctets
2831 (u32)session[i].cout); // downrxoctets
2832
2833 session[i].pin = session[i].cin = 0;
2834 session[i].pout = session[i].cout = 0;
2835 }
2836
2837 if (f) fclose(f);
2838 }
2839
2840 // Main program
2841 int main(int argc, char *argv[])
2842 {
2843 int o;
2844 int optdebug = 0;
2845
2846 _program_name = strdup(argv[0]);
2847
2848 time(&basetime); // start clock
2849
2850 // scan args
2851 while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
2852 {
2853 switch (o)
2854 {
2855 case 'd':
2856 // Double fork to detach from terminal
2857 if (fork()) exit(0);
2858 if (fork()) exit(0);
2859 break;
2860 case 'v':
2861 optdebug++;
2862 break;
2863 case 'h':
2864 snprintf(hostname, sizeof(hostname), "%s", optarg);
2865 break;
2866 case '?':
2867 default:
2868 printf("Args are:\n"
2869 "\t-d\tDetach from terminal\n"
2870 "\t-c <file>\tConfig file\n"
2871 "\t-h <hostname>\tForce hostname\n"
2872 "\t-a <address>\tUse specific address\n"
2873 "\t-v\t\tDebug\n");
2874
2875 return (0);
2876 break;
2877 }
2878 }
2879
2880 // Start the timer routine off
2881 time(&time_now);
2882 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
2883 signal(SIGALRM, sigalrm_handler);
2884 siginterrupt(SIGALRM, 0);
2885
2886 initiptables();
2887 initplugins();
2888 initdata();
2889
2890 config->debug = optdebug;
2891
2892 init_tbf();
2893 init_cli(hostname);
2894 read_config_file();
2895
2896 log(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
2897 log(0, 0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
2898 log(0, 0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
2899 {
2900 struct rlimit rlim;
2901 rlim.rlim_cur = RLIM_INFINITY;
2902 rlim.rlim_max = RLIM_INFINITY;
2903 // Remove the maximum core size
2904 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
2905 log(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
2906 // Make core dumps go to /tmp
2907 chdir("/tmp");
2908 }
2909
2910 if (config->scheduler_fifo)
2911 {
2912 int ret;
2913 struct sched_param params = {0};
2914 params.sched_priority = 1;
2915
2916 if (get_nprocs() < 2)
2917 {
2918 log(0, 0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
2919 config->scheduler_fifo = 0;
2920 }
2921 else
2922 {
2923 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
2924 {
2925 log(1, 0, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
2926 }
2927 else
2928 {
2929 log(0, 0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
2930 config->scheduler_fifo = 0;
2931 }
2932 }
2933 }
2934
2935 /* Set up the cluster communications port. */
2936 if (cluster_init(config->bind_address) < 0)
2937 exit(1);
2938
2939 #ifdef BGP
2940 signal(SIGPIPE, SIG_IGN);
2941 bgp_setup(config->as_number);
2942 bgp_add_route(config->bind_address, 0xffffffff);
2943 if (*config->bgp_peer[0])
2944 bgp_start(&bgp_peers[0], config->bgp_peer[0],
2945 config->bgp_peer_as[0], 0); /* 0 = routing disabled */
2946
2947 if (*config->bgp_peer[1])
2948 bgp_start(&bgp_peers[1], config->bgp_peer[1],
2949 config->bgp_peer_as[1], 0);
2950 #endif /* BGP */
2951
2952 inittun();
2953 log(1, 0, 0, 0, "Set up on interface %s\n", config->tundevice);
2954
2955 initudp();
2956 initrad();
2957 initippool();
2958
2959 read_state();
2960
2961 signal(SIGHUP, sighup_handler);
2962 signal(SIGTERM, sigterm_handler);
2963 signal(SIGINT, sigterm_handler);
2964 signal(SIGQUIT, sigquit_handler);
2965 signal(SIGCHLD, sigchild_handler);
2966
2967 // Prevent us from getting paged out
2968 if (config->lock_pages)
2969 {
2970 if (!mlockall(MCL_CURRENT))
2971 log(1, 0, 0, 0, "Locking pages into memory\n");
2972 else
2973 log(0, 0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
2974 }
2975
2976 alarm(1);
2977
2978 // Drop privileges here
2979 if (config->target_uid > 0 && geteuid() == 0)
2980 setuid(config->target_uid);
2981
2982 mainloop();
2983
2984 #ifdef BGP
2985 /* try to shut BGP down cleanly; with luck the sockets will be
2986 writable since we're out of the select */
2987 {
2988 int i;
2989 for (i = 0; i < BGP_NUM_PEERS; i++)
2990 if (bgp_peers[i].state == Established)
2991 bgp_stop(&bgp_peers[i]);
2992 }
2993 #endif /* BGP */
2994
2995 /* remove plugins (so cleanup code gets run) */
2996 plugins_done();
2997
2998 /* kill CLI children */
2999 signal(SIGTERM, SIG_IGN);
3000 kill(0, SIGTERM);
3001 return 0;
3002 }
3003
3004 void sighup_handler(int junk)
3005 {
3006 if (log_stream && log_stream != stderr)
3007 {
3008 fclose(log_stream);
3009 log_stream = NULL;
3010 }
3011
3012 read_config_file();
3013 }
3014
3015 void sigalrm_handler(int junk)
3016 {
3017 // Log current traffic stats
3018
3019 snprintf(config->bandwidth, sizeof(config->bandwidth),
3020 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3021 (udp_rx / 1024.0 / 1024.0 * 8),
3022 (eth_tx / 1024.0 / 1024.0 * 8),
3023 (eth_rx / 1024.0 / 1024.0 * 8),
3024 (udp_tx / 1024.0 / 1024.0 * 8),
3025 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3026 udp_rx_pkt, eth_rx_pkt);
3027
3028 udp_tx = udp_rx = 0;
3029 udp_rx_pkt = eth_rx_pkt = 0;
3030 eth_tx = eth_rx = 0;
3031
3032 if (config->dump_speed)
3033 printf("%s\n", config->bandwidth);
3034
3035 // Update the internal time counter
3036 time(&time_now);
3037 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3038 alarm(1);
3039
3040 {
3041 // Run timer hooks
3042 struct param_timer p = { time_now };
3043 run_plugins(PLUGIN_TIMER, &p);
3044 }
3045
3046 }
3047
3048 void sigterm_handler(int junk)
3049 {
3050 log(1, 0, 0, 0, "Shutting down cleanly\n");
3051 if (config->save_state)
3052 dump_state();
3053
3054 main_quit++;
3055 }
3056
3057 void sigquit_handler(int junk)
3058 {
3059 int i;
3060
3061 log(1, 0, 0, 0, "Shutting down without saving sessions\n");
3062 for (i = 1; i < MAXSESSION; i++)
3063 {
3064 if (session[i].opened)
3065 sessionkill(i, "L2TPNS Closing");
3066 }
3067 for (i = 1; i < MAXTUNNEL; i++)
3068 {
3069 if (tunnel[i].ip || tunnel[i].state)
3070 tunnelshutdown(i, "L2TPNS Closing");
3071 }
3072
3073 main_quit++;
3074 }
3075
3076 void sigchild_handler(int signal)
3077 {
3078 while (waitpid(-1, NULL, WNOHANG) > 0)
3079 ;
3080 }
3081
3082 void read_state()
3083 {
3084 struct stat sb;
3085 int i;
3086 ippoolt itmp;
3087 FILE *f;
3088 char magic[sizeof(DUMP_MAGIC)-1];
3089 u32 buf[2];
3090
3091 if (!config->save_state)
3092 {
3093 unlink(STATEFILE);
3094 return;
3095 }
3096
3097 if (stat(STATEFILE, &sb) < 0)
3098 {
3099 unlink(STATEFILE);
3100 return;
3101 }
3102
3103 if (sb.st_mtime < (time(NULL) - 60))
3104 {
3105 log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
3106 unlink(STATEFILE);
3107 return;
3108 }
3109
3110 f = fopen(STATEFILE, "r");
3111 unlink(STATEFILE);
3112
3113 if (!f)
3114 {
3115 log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3116 exit(1);
3117 }
3118
3119 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3120 {
3121 log(0, 0, 0, 0, "Bad state file magic\n");
3122 exit(1);
3123 }
3124
3125 log(1, 0, 0, 0, "Reading state information\n");
3126 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3127 {
3128 log(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3129 exit(1);
3130 }
3131
3132 if (buf[0] > ip_pool_size)
3133 {
3134 log(0, 0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3135 exit(1);
3136 }
3137
3138 log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
3139 for (i = 0; i < buf[0]; i++)
3140 {
3141 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3142 {
3143 log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3144 exit(1);
3145 }
3146
3147 if (itmp.address != ip_address_pool[i].address)
3148 {
3149 log(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3150 exit(1);
3151 }
3152
3153 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3154 }
3155
3156 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3157 {
3158 log(0, 0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3159 exit(1);
3160 }
3161
3162 log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3163 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3164 {
3165 log(0, 0, 0, 0, "Error reading tunnel data from state file\n");
3166 exit(1);
3167 }
3168
3169 for (i = 0; i < MAXTUNNEL; i++)
3170 {
3171 tunnel[i].controlc = 0;
3172 tunnel[i].controls = NULL;
3173 tunnel[i].controle = NULL;
3174 if (*tunnel[i].hostname)
3175 log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3176 }
3177
3178 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3179 {
3180 log(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
3181 exit(1);
3182 }
3183
3184 log(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
3185 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3186 {
3187 log(0, 0, 0, 0, "Error reading session data from state file\n");
3188 exit(1);
3189 }
3190
3191 for (i = 0; i < MAXSESSION; i++)
3192 {
3193 session[i].tbf_in = 0;
3194 session[i].tbf_out = 0;
3195 if (session[i].opened)
3196 {
3197 log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
3198 if (session[i].ip)
3199 sessionsetup(session[i].tunnel, i);
3200 }
3201 }
3202
3203 fclose(f);
3204 log(0, 0, 0, 0, "Loaded saved state information\n");
3205 }
3206
3207 void dump_state()
3208 {
3209 FILE *f;
3210 u32 buf[2];
3211
3212 if (!config->save_state)
3213 return;
3214
3215 do {
3216 if (!(f = fopen(STATEFILE, "w")))
3217 break;
3218
3219 log(1, 0, 0, 0, "Dumping state information\n");
3220
3221 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC)-1, 1, f) != 1) break;
3222
3223 log(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3224 buf[0] = ip_pool_size;
3225 buf[1] = sizeof(ippoolt);
3226 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3227 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size) break;
3228
3229 log(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3230 buf[0] = MAXTUNNEL;
3231 buf[1] = sizeof(tunnelt);
3232 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3233 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL) break;
3234
3235 log(2, 0, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3236 buf[0] = MAXSESSION;
3237 buf[1] = sizeof(sessiont);
3238 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3239 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION) break;
3240
3241 if (fclose(f) == 0) return; // OK
3242 } while (0);
3243
3244 log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3245 unlink(STATEFILE);
3246 }
3247
3248 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
3249 {
3250 MD5_CTX ctx;
3251 *challenge_response = NULL;
3252
3253 if (!*config->l2tpsecret)
3254 {
3255 log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3256 return;
3257 }
3258
3259 log(4, 0, 0, 0, " Building challenge response for CHAP request\n");
3260
3261 *challenge_response = (char *)calloc(17, 1);
3262
3263 MD5Init(&ctx);
3264 MD5Update(&ctx, &id, 1);
3265 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3266 MD5Update(&ctx, challenge, challenge_length);
3267 MD5Final(*challenge_response, &ctx);
3268
3269 return;
3270 }
3271
3272 static int facility_value(char *name)
3273 {
3274 int i;
3275 for (i = 0; facilitynames[i].c_name; i++)
3276 {
3277 if (strcmp(facilitynames[i].c_name, name) == 0)
3278 return facilitynames[i].c_val;
3279 }
3280 return 0;
3281 }
3282
3283 void update_config()
3284 {
3285 int i;
3286 static int timeout = 0;
3287 static int interval = 0;
3288
3289 // Update logging
3290 closelog();
3291 syslog_log = 0;
3292 if (log_stream)
3293 {
3294 fclose(log_stream);
3295 log_stream = NULL;
3296 }
3297 if (*config->log_filename)
3298 {
3299 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3300 {
3301 char *p = config->log_filename + 7;
3302 if (*p)
3303 {
3304 openlog("l2tpns", LOG_PID, facility_value(p));
3305 syslog_log = 1;
3306 }
3307 }
3308 else if (strchr(config->log_filename, '/') == config->log_filename)
3309 {
3310 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3311 {
3312 fseek(log_stream, 0, SEEK_END);
3313 setbuf(log_stream, NULL);
3314 }
3315 else
3316 {
3317 log_stream = stderr;
3318 setbuf(log_stream, NULL);
3319 }
3320 }
3321 }
3322 else
3323 {
3324 log_stream = stderr;
3325 setbuf(log_stream, NULL);
3326 }
3327
3328
3329 // Update radius
3330 config->numradiusservers = 0;
3331 for (i = 0; i < MAXRADSERVER; i++)
3332 if (config->radiusserver[i])
3333 {
3334 config->numradiusservers++;
3335 // Set radius port: if not set, take the port from the
3336 // first radius server. For the first radius server,
3337 // take the #defined default value from l2tpns.h
3338
3339 // test twice, In case someone works with
3340 // a secondary radius server without defining
3341 // a primary one, this will work even then.
3342 if (i>0 && !config->radiusport[i])
3343 config->radiusport[i] = config->radiusport[i-1];
3344 if (!config->radiusport[i])
3345 config->radiusport[i] = RADPORT;
3346 }
3347
3348 if (!config->numradiusservers)
3349 {
3350 log(0, 0, 0, 0, "No RADIUS servers defined!\n");
3351 }
3352
3353 config->num_radfds = 2 << RADIUS_SHIFT;
3354
3355 // Update plugins
3356 for (i = 0; i < MAXPLUGINS; i++)
3357 {
3358 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3359 continue;
3360 if (*config->plugins[i])
3361 {
3362 // Plugin added
3363 add_plugin(config->plugins[i]);
3364 }
3365 else if (*config->old_plugins[i])
3366 {
3367 // Plugin removed
3368 remove_plugin(config->old_plugins[i]);
3369 }
3370 }
3371 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3372 if (!config->cleanup_interval) config->cleanup_interval = 10;
3373 if (!config->multi_read_count) config->multi_read_count = 10;
3374 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3375 if (!*config->cluster_interface)
3376 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3377
3378 if (!config->cluster_hb_interval)
3379 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3380
3381 if (!config->cluster_hb_timeout)
3382 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3383
3384 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3385 {
3386 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3387 // late, ensure we're sufficiently larger than that
3388 int t = 4 * config->cluster_hb_interval + 11;
3389
3390 if (config->cluster_hb_timeout < t)
3391 {
3392 log(0,0,0,0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3393 config->cluster_hb_timeout = t;
3394 }
3395
3396 // Push timing changes to the slaves immediately if we're the master
3397 if (config->cluster_iam_master)
3398 cluster_heartbeat();
3399
3400 interval = config->cluster_hb_interval;
3401 timeout = config->cluster_hb_timeout;
3402 }
3403
3404 config->reload_config = 0;
3405 }
3406
3407 void read_config_file()
3408 {
3409 FILE *f;
3410
3411 if (!config->config_file) return;
3412 if (!(f = fopen(config->config_file, "r"))) {
3413 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3414 return;
3415 }
3416
3417 log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
3418 cli_do_file(f);
3419 log(3, 0, 0, 0, "Done reading config file\n");
3420 fclose(f);
3421 update_config();
3422 }
3423
3424 int sessionsetup(tunnelidt t, sessionidt s)
3425 {
3426 // A session now exists, set it up
3427 ipt ip;
3428 char *user;
3429 sessionidt i;
3430 int r;
3431
3432 CSTAT(call_sessionsetup);
3433
3434
3435 log(3, session[s].ip, s, t, "Doing session setup for session\n");
3436
3437 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3438 {
3439 assign_ip_address(s);
3440 if (session[s].ip)
3441 log(3, 0, s, t, " No IP allocated. Assigned %s from pool\n",
3442 inet_toa(htonl(session[s].ip)));
3443 else
3444 log(0, 0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3445 }
3446
3447
3448 // Make sure this is right
3449 session[s].tunnel = t;
3450
3451 // zap old sessions with same IP and/or username
3452 // Don't kill gardened sessions - doing so leads to a DoS
3453 // from someone who doesn't need to know the password
3454 {
3455 ip = session[s].ip;
3456 user = session[s].user;
3457 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3458 {
3459 if (i == s) continue;
3460 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3461 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3462 sessionkill(i, "Duplicate session for users");
3463 }
3464 }
3465
3466 // Add the route for this session.
3467 //
3468 // Static IPs need to be routed. Anything else
3469 // is part of the IP address pool and is already routed,
3470 // it just needs to be added to the IP cache.
3471 if (session[s].ip_pool_index == -1) // static ip
3472 routeset(s, session[s].ip, 0, 0, 1);
3473 else
3474 cache_ipmap(session[s].ip, s);
3475
3476 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3477 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1);
3478
3479 if (!session[s].sid) { // did this session just finish radius?
3480 log(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
3481 sendipcp(t, s);
3482 session[s].sid = ++last_sid;
3483 }
3484
3485 // Run the plugin's against this new session.
3486 {
3487 struct param_new_session data = { &tunnel[t], &session[s] };
3488 run_plugins(PLUGIN_NEW_SESSION, &data);
3489 }
3490
3491 // Force throttling on or off (Actually : refresh the current throttling status)
3492 // This has the advantage of cleaning up after another throttled user who may have left
3493 // firewall rules lying around
3494 throttle_session(s, session[s].throttle);
3495
3496 session[s].last_packet = time_now;
3497
3498 {
3499 char *sessionip, *tunnelip;
3500 sessionip = strdup(inet_toa(htonl(session[s].ip)));
3501 tunnelip = strdup(inet_toa(htonl(tunnel[t].ip)));
3502 log(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
3503 session[s].user, sessionip, tunnelip, tunnel[t].hostname);
3504 if (sessionip) free(sessionip);
3505 if (tunnelip) free(tunnelip);
3506 }
3507
3508 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3509
3510 return 1; // RADIUS OK and IP allocated, done...
3511 }
3512
3513 //
3514 // This session just got dropped on us by the master or something.
3515 // Make sure our tables up up to date...
3516 //
3517 int load_session(sessionidt s, sessiont *new)
3518 {
3519 int i;
3520
3521 // Sanity checks.
3522 if (new->ip_pool_index >= MAXIPPOOL ||
3523 new->tunnel >= MAXTUNNEL) {
3524 log(0,0,s,0, "Strange session update received!\n");
3525 // FIXME! What to do here?
3526 return 0;
3527 }
3528
3529 //
3530 // Ok. All sanity checks passed. Now we're committed to
3531 // loading the new session.
3532 //
3533
3534 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3535
3536
3537 if (new->ip != session[s].ip) // Changed ip. fix up hash tables.
3538 {
3539 if (session[s].ip) // If there's an old one, remove it.
3540 {
3541 // Remove any routes if the IP has changed
3542 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3543 {
3544 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3545 session[s].route[i].ip = 0;
3546 }
3547
3548 if (session[s].ip_pool_index == -1) // static IP
3549 routeset(s, session[s].ip, 0, 0, 0);
3550 else // It's part of the IP pool, remove it manually.
3551 uncache_ipmap(session[s].ip);
3552 }
3553
3554 if (new->ip) { // If there's a new one, add it.
3555 if (new->ip_pool_index == -1)
3556 routeset(s, new->ip, 0, 0, 1);
3557 else
3558 cache_ipmap(new->ip, s);
3559 }
3560 }
3561
3562 // Update routed networks
3563 for (i = 0; i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3564 {
3565 if (new->route[i].ip == session[s].route[i].ip &&
3566 new->route[i].mask == session[s].route[i].mask)
3567 continue;
3568
3569 if (session[s].route[i].ip) // Remove the old one if it exists.
3570 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3571
3572 if (new->route[i].ip) // Add the new one if it exists.
3573 routeset(s, new->route[i].ip, new->route[i].mask, new->ip, 1);
3574 }
3575
3576 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3577 // for walking the sessions to forward byte counts to the master.
3578 config->cluster_highest_sessionid = s;
3579
3580 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3581
3582 // Do fixups into address pool.
3583 if (new->ip_pool_index != -1)
3584 fix_address_pool(s);
3585
3586 return 1;
3587 }
3588
3589 #ifdef RINGBUFFER
3590 void ringbuffer_dump(FILE *stream)
3591 {
3592 int i = ringbuffer->head;
3593
3594 while (i != ringbuffer->tail)
3595 {
3596 if (*ringbuffer->buffer[i].message)
3597 fprintf(stream, "%d-%s", ringbuffer->buffer[i].level, ringbuffer->buffer[i].message);
3598 if (++i == ringbuffer->tail) break;
3599 if (i == RINGBUFFER_SIZE) i = 0;
3600 }
3601 }
3602 #endif
3603
3604 void initplugins()
3605 {
3606 int i;
3607
3608 loaded_plugins = ll_init();
3609 // Initialize the plugins to nothing
3610 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3611 plugins[i] = ll_init();
3612 }
3613
3614 static void *open_plugin(char *plugin_name, int load)
3615 {
3616 char path[256] = "";
3617
3618 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3619 log(2, 0, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3620 return dlopen(path, RTLD_NOW);
3621 }
3622
3623 void add_plugin(char *plugin_name)
3624 {
3625 static struct pluginfuncs funcs = {
3626 _log,
3627 _log_hex,
3628 inet_toa,
3629 sessionbyuser,
3630 sessiontbysessionidt,
3631 sessionidtbysessiont,
3632 sessionkill,
3633 radiusnew,
3634 radiussend,
3635 };
3636
3637 void *p = open_plugin(plugin_name, 1);
3638 int (*initfunc)(struct pluginfuncs *);
3639 int i;
3640
3641 if (!p)
3642 {
3643 log(1, 0, 0, 0, " Plugin load failed: %s\n", dlerror());
3644 return;
3645 }
3646
3647 if (ll_contains(loaded_plugins, p))
3648 {
3649 dlclose(p);
3650 return;
3651 }
3652
3653 {
3654 int *v = dlsym(p, "__plugin_api_version");
3655 if (!v || *v != PLUGIN_API_VERSION)
3656 {
3657 log(1, 0, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
3658 dlclose(p);
3659 return;
3660 }
3661 }
3662
3663 if ((initfunc = dlsym(p, "plugin_init")))
3664 {
3665 if (!initfunc(&funcs))
3666 {
3667 log(1, 0, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
3668 dlclose(p);
3669 return;
3670 }
3671 }
3672
3673 ll_push(loaded_plugins, p);
3674
3675 for (i = 0; i < max_plugin_functions; i++)
3676 {
3677 void *x;
3678 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3679 {
3680 log(3, 0, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
3681 ll_push(plugins[i], x);
3682 }
3683 }
3684
3685 log(2, 0, 0, 0, " Loaded plugin %s\n", plugin_name);
3686 }
3687
3688 static void run_plugin_done(void *plugin)
3689 {
3690 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
3691
3692 if (donefunc)
3693 donefunc();
3694 }
3695
3696 void remove_plugin(char *plugin_name)
3697 {
3698 void *p = open_plugin(plugin_name, 0);
3699 int i;
3700
3701 if (!p)
3702 return;
3703
3704 for (i = 0; i < max_plugin_functions; i++)
3705 {
3706 void *x;
3707 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3708 ll_delete(plugins[i], x);
3709 }
3710
3711 if (ll_contains(loaded_plugins, p))
3712 {
3713 ll_delete(loaded_plugins, p);
3714 run_plugin_done(p);
3715 }
3716
3717 dlclose(p);
3718 log(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
3719 }
3720
3721 int run_plugins(int plugin_type, void *data)
3722 {
3723 int (*func)(void *data);
3724 if (!plugins[plugin_type] || plugin_type > max_plugin_functions) return 1;
3725
3726 ll_reset(plugins[plugin_type]);
3727 while ((func = ll_next(plugins[plugin_type])))
3728 {
3729 int rc;
3730 rc = func(data);
3731 if (rc == PLUGIN_RET_STOP) return 1;
3732 if (rc == PLUGIN_RET_ERROR) return 0;
3733 }
3734 return 1;
3735 }
3736
3737 void plugins_done()
3738 {
3739 void *p;
3740
3741 ll_reset(loaded_plugins);
3742 while ((p = ll_next(loaded_plugins)))
3743 run_plugin_done(p);
3744 }
3745
3746 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
3747 {
3748 char *resp;
3749 int l;
3750 struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
3751
3752
3753 if (log_stream && config->debug >= 4)
3754 {
3755 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
3756 dump_packet(buf, log_stream);
3757 }
3758
3759 resp = calloc(1400, 1);
3760 l = new_packet(PKT_RESP_ERROR, resp);
3761 *(int *)(resp + 6) = *(int *)(buf + 6);
3762
3763 param.type = ntohs(*(short *)(buf + 2));
3764 param.id = ntohl(*(int *)(buf + 6));
3765 param.data_length = ntohs(*(short *)(buf + 4)) - 10;
3766 param.data = (param.data_length > 0) ? (char *)(buf + 10) : NULL;
3767 param.response = resp;
3768 param.response_length = l;
3769
3770 run_plugins(PLUGIN_CONTROL, &param);
3771
3772 if (param.send_response)
3773 {
3774 send_packet(controlfd, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), param.response, param.response_length);
3775 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent Control packet response\n");
3776 }
3777
3778 free(resp);
3779 }
3780
3781 /*
3782 * HACK
3783 * Go through all of the tunnels and do some cleanups
3784 */
3785 void tunnel_clean()
3786 {
3787 int i;
3788
3789 log(1, 0, 0, 0, "Cleaning tunnels array\n");
3790
3791 for (i = 1; i < MAXTUNNEL; i++)
3792 {
3793 if (!tunnel[i].ip
3794 || !*tunnel[i].hostname
3795 || (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
3796 {
3797 tunnelclear(i);
3798 }
3799 }
3800 }
3801
3802 void tunnelclear(tunnelidt t)
3803 {
3804 if (!t) return;
3805 memset(&tunnel[t], 0, sizeof(tunnel[t]));
3806 tunnel[t].state = TUNNELFREE;
3807 }
3808
3809 tunnelidt new_tunnel()
3810 {
3811 tunnelidt i;
3812 for (i = 1; i < MAXTUNNEL; i++)
3813 {
3814 if (tunnel[i].state == TUNNELFREE)
3815 {
3816 log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
3817 if (i > config->cluster_highest_tunnelid)
3818 config->cluster_highest_tunnelid = i;
3819 return i;
3820 }
3821 }
3822 log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
3823 return 0;
3824 }
3825
3826 //
3827 // We're becoming the master. Do any required setup..
3828 //
3829 // This is principally telling all the plugins that we're
3830 // now a master, and telling them about all the sessions
3831 // that are active too..
3832 //
3833 void become_master(void)
3834 {
3835 int s;
3836 run_plugins(PLUGIN_BECOME_MASTER, NULL);
3837
3838 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3839 if (!session[s].tunnel) // Not an in-use session.
3840 continue;
3841
3842 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
3843 }
3844 }
3845
3846
3847
3848 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
3849 {
3850 int s, i;
3851 int count = 0;
3852 int buckets[64];
3853
3854 if (CLI_HELP_REQUESTED)
3855 return CLI_HELP_NO_ARGS;
3856
3857 time(&time_now);
3858 for (i = 0; i < 64;++i) buckets[i] = 0;
3859
3860 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3861 int idle;
3862 if (!session[s].tunnel)
3863 continue;
3864
3865 idle = time_now - session[s].last_packet;
3866 idle /= 5 ; // In multiples of 5 seconds.
3867 if (idle < 0)
3868 idle = 0;
3869 if (idle > 63)
3870 idle = 63;
3871
3872 ++count;
3873 ++buckets[idle];
3874 }
3875
3876 for (i = 0; i < 63; ++i) {
3877 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
3878 }
3879 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
3880 cli_print(cli, "%d total sessions open.", count);
3881 return CLI_OK;
3882 }
3883
3884 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
3885 {
3886 int s, i;
3887 int count = 0;
3888 int buckets[64];
3889
3890 if (CLI_HELP_REQUESTED)
3891 return CLI_HELP_NO_ARGS;
3892
3893 time(&time_now);
3894 for (i = 0; i < 64;++i) buckets[i] = 0;
3895
3896 for (s = 1; s <= config->cluster_highest_sessionid ; ++s) {
3897 int open = 0, d;
3898 if (!session[s].tunnel)
3899 continue;
3900
3901 d = time_now - session[s].opened;
3902 if (d < 0)
3903 d = 0;
3904 while (d > 1 && open < 32) {
3905 ++open;
3906 d >>= 1; // half.
3907 }
3908 ++count;
3909 ++buckets[open];
3910 }
3911
3912 s = 1;
3913 for (i = 0; i < 30; ++i) {
3914 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
3915 s <<= 1;
3916 }
3917 cli_print(cli, "%d total sessions open.", count);
3918 return CLI_OK;
3919 }