32fce1baa09ecfeccb4b57f97dd2ab8c20805126
[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 1.9 2004/06/28 02:43:13 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 #define __USE_GNU
26 #include <string.h>
27 #include <sys/ioctl.h>
28 #include <sys/socket.h>
29 #include <sys/stat.h>
30 #include <sys/time.h>
31 #include <sys/resource.h>
32 #include <sys/wait.h>
33 #include <linux/if.h>
34 #include <stddef.h>
35 #include <time.h>
36 #include <dlfcn.h>
37 #include <unistd.h>
38 #include <sched.h>
39 #include <sys/sysinfo.h>
40 #include <libcli.h>
41
42 #include "md5.h"
43 #include "l2tpns.h"
44 #include "cluster.h"
45 #include "plugin.h"
46 #include "ll.h"
47 #include "constants.h"
48 #include "control.h"
49 #include "util.h"
50 #include "tbf.h"
51
52 // Globals
53 struct configt *config = NULL; // all configuration
54 int tapfd = -1; // tap interface file handle
55 int udpfd = -1; // UDP file handle
56 int controlfd = -1; // Control signal handle
57 int snoopfd = -1; // UDP file handle for sending out intercept data
58 int *radfds = NULL; // RADIUS requests file handles
59 int ifrfd = -1; // File descriptor for routing, etc
60 time_t basetime = 0; // base clock
61 char hostname[1000] = ""; // us.
62 u16 tapmac[3]; // MAC of tap interface
63 int tapidx; // ifr_ifindex of tap device
64 u32 sessionid = 0; // session id for radius accounting
65 int syslog_log = 0; // are we logging to syslog
66 FILE *log_stream = NULL;
67 struct sockaddr_in snoop_addr = {0};
68 extern int cluster_sockfd;
69 u32 last_sid = 0;
70 int clifd = 0;
71 sessionidt *cli_session_kill = NULL;
72 tunnelidt *cli_tunnel_kill = NULL;
73 static void *ip_hash[256];
74 u32 udp_tx = 0, udp_rx = 0, udp_rx_pkt = 0;
75 u32 eth_tx = 0, eth_rx = 0, eth_rx_pkt = 0;
76 u32 ip_pool_size = 1;
77 time_t time_now = 0;
78 char time_now_string[64] = {0};
79 char main_quit = 0;
80 char *_program_name = NULL;
81 linked_list *loaded_plugins;
82 linked_list *plugins[MAX_PLUGIN_TYPES];
83
84 #ifdef BGP
85 #include "bgp.h"
86 struct bgp_peer *bgp_peers = 0;
87 struct bgp_route_list *bgp_routes = 0;
88 int bgp_configured = 0;
89 #endif /* BGP */
90
91 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
92 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(struct configt, MEMBER), membersize(struct configt, MEMBER), TYPE }
93
94 struct config_descriptt config_values[] = {
95 CONFIG("debug", debug, INT),
96 CONFIG("log_file", log_filename, STRING),
97 CONFIG("l2tp_secret", l2tpsecret, STRING),
98 CONFIG("primary_dns", default_dns1, IP),
99 CONFIG("secondary_dns", default_dns2, IP),
100 CONFIG("save_state", save_state, BOOL),
101 CONFIG("primary_radius", radiusserver[0], IP),
102 CONFIG("secondary_radius", radiusserver[1], IP),
103 CONFIG("radius_accounting", radius_accounting, BOOL),
104 CONFIG("radius_secret", radiussecret, STRING),
105 CONFIG("bind_address", bind_address, IP),
106 CONFIG("send_garp", send_garp, BOOL),
107 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
108 CONFIG("accounting_dir", accounting_dir, STRING),
109 CONFIG("setuid", target_uid, INT),
110 CONFIG("dump_speed", dump_speed, BOOL),
111 CONFIG("cleanup_interval", cleanup_interval, INT),
112 CONFIG("multi_read_count", multi_read_count, INT),
113 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
114 CONFIG("icmp_rate", icmp_rate, INT),
115 CONFIG("cluster_address", cluster_address, IP),
116 CONFIG("cluster_interface", cluster_interface, STRING),
117 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
118 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
119 #ifdef BGP
120 CONFIG("as_number", as_number, SHORT),
121 CONFIG("bgp_peer1", bgp_peer[0], STRING),
122 CONFIG("bgp_peer1_as", bgp_peer_as[0], SHORT),
123 CONFIG("bgp_peer2", bgp_peer[1], STRING),
124 CONFIG("bgp_peer2_as", bgp_peer_as[1], SHORT),
125 #endif /* BGP */
126 { NULL, 0, 0, 0 },
127 };
128
129 char *plugin_functions[] = {
130 NULL,
131 "plugin_pre_auth",
132 "plugin_post_auth",
133 "plugin_packet_rx",
134 "plugin_packet_tx",
135 "plugin_timer",
136 "plugin_new_session",
137 "plugin_kill_session",
138 "plugin_control",
139 "plugin_radius_response",
140 "plugin_become_master",
141 "plugin_new_session_master",
142 };
143
144 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
145
146 tunnelt *tunnel = NULL; // 1000 * 45 = 45000 = 45k
147 sessiont *session = NULL; // 5000 * 213 = 1065000 = 1 Mb
148 sessioncountt *sess_count = NULL;
149 radiust *radius = NULL;
150 ippoolt *ip_address_pool = NULL;
151 controlt *controlfree = 0;
152 struct Tstats *_statistics = NULL;
153 #ifdef RINGBUFFER
154 struct Tringbuffer *ringbuffer = NULL;
155 #endif
156
157 void sigalrm_handler(int);
158 void sighup_handler(int);
159 void sigterm_handler(int);
160 void sigquit_handler(int);
161 void sigchild_handler(int);
162 void read_config_file();
163 void read_state();
164 void dump_state();
165 void tunnel_clean();
166 tunnelidt new_tunnel();
167 void update_config();
168
169 static void cache_ipmap(ipt ip, int s);
170 static void uncache_ipmap(ipt ip);
171
172 // return internal time (10ths since run)
173 clockt now(void)
174 {
175 struct timeval t;
176 gettimeofday(&t, 0);
177 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
178 }
179
180 // work out a retry time based on try number
181 clockt backoff(u8 try)
182 {
183 if (try > 5) try = 5; // max backoff
184 return now() + 10 * (1 << try);
185 }
186
187 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
188 {
189 static char message[65536] = {0};
190 static char message2[65536] = {0};
191 va_list ap;
192
193 #ifdef RINGBUFFER
194 if (ringbuffer)
195 {
196 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
197 ringbuffer->tail = 0;
198 if (ringbuffer->tail == ringbuffer->head)
199 if (++ringbuffer->head >= RINGBUFFER_SIZE)
200 ringbuffer->head = 0;
201
202 ringbuffer->buffer[ringbuffer->tail].level = level;
203 ringbuffer->buffer[ringbuffer->tail].address = address;
204 ringbuffer->buffer[ringbuffer->tail].session = s;
205 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
206 va_start(ap, format);
207 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
208 va_end(ap);
209 }
210 #endif
211
212 if (config->debug < level) return;
213
214 va_start(ap, format);
215 if (log_stream)
216 {
217 vsnprintf(message2, 65535, format, ap);
218 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
219 fprintf(log_stream, "%s", message);
220 }
221 else if (syslog_log)
222 {
223 vsnprintf(message2, 65535, format, ap);
224 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
225 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
226 }
227 va_end(ap);
228 }
229
230 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize)
231 {
232 int i, j;
233 const u8 *d = (const u8 *)data;
234
235 if (config->debug < level) return;
236
237 // No support for log_hex to syslog
238 if (log_stream)
239 {
240 log(level, address, s, t, "%s (%d bytes):\n", title, maxsize);
241 setvbuf(log_stream, NULL, _IOFBF, 16384);
242
243 for (i = 0; i < maxsize; )
244 {
245 fprintf(log_stream, "%4X: ", i);
246 for (j = i; j < maxsize && j < (i + 16); j++)
247 {
248 fprintf(log_stream, "%02X ", d[j]);
249 if (j == i + 7)
250 fputs(": ", log_stream);
251 }
252
253 for (; j < i + 16; j++)
254 {
255 fputs(" ", log_stream);
256 if (j == i + 7)
257 fputs(": ", log_stream);
258 }
259
260 fputs(" ", log_stream);
261 for (j = i; j < maxsize && j < (i + 16); j++)
262 {
263 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
264 fputc(d[j], log_stream);
265 else
266 fputc('.', log_stream);
267
268 if (j == i + 7)
269 fputs(" ", log_stream);
270 }
271
272 i = j;
273 fputs("\n", log_stream);
274 }
275
276 fflush(log_stream);
277 setbuf(log_stream, NULL);
278 }
279 }
280
281
282 // Add a route
283 //
284 // This adds it to the routing table, advertises it
285 // via iBGP if enabled, and stuffs it into the
286 // 'sessionbyip' cache.
287 //
288 // 'ip' and 'mask' must be in _host_ order.
289 //
290 void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
291 {
292 struct rtentry r;
293 int i;
294
295 if (!mask) mask = 0xffffffff;
296
297 ip &= mask; // Force the ip to be the first one in the route.
298
299 memset(&r, 0, sizeof(r));
300 r.rt_dev = config->tapdevice;
301 r.rt_dst.sa_family = AF_INET;
302 *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
303 r.rt_gateway.sa_family = AF_INET;
304 *(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
305 r.rt_genmask.sa_family = AF_INET;
306 *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
307 r.rt_flags = (RTF_UP | RTF_STATIC);
308 if (gw)
309 r.rt_flags |= RTF_GATEWAY;
310 else if (mask == 0xffffffff)
311 r.rt_flags |= RTF_HOST;
312
313 log(1, ip, 0, 0, "Route %s %u.%u.%u.%u/%u.%u.%u.%u %u.%u.%u.%u\n",
314 add ? "add" : "del",
315 ip >> 24, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff,
316 mask >> 24, mask >> 16 & 0xff, mask >> 8 & 0xff, mask & 0xff,
317 gw >> 24, gw >> 16 & 0xff, gw >> 8 & 0xff, gw & 0xff);
318
319 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
320 log(0, 0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
321
322 #ifdef BGP
323 if (add)
324 bgp_add_route(htonl(ip), htonl(mask));
325 else
326 bgp_del_route(htonl(ip), htonl(mask));
327 #endif /* BGP */
328
329 // Add/Remove the IPs to the 'sessionbyip' cache.
330 // Note that we add the zero address in the case of
331 // a network route. Roll on CIDR.
332
333 // Note that 's == 0' implies this is the address pool.
334 // We still cache it here, because it will pre-fill
335 // the malloc'ed tree.
336
337 if (s)
338 {
339 if (!add) // Are we deleting a route?
340 s = 0; // Caching the session as '0' is the same as uncaching.
341
342 for (i = ip; (i&mask) == (ip&mask) ; ++i)
343 cache_ipmap(i, s);
344 }
345 }
346
347 // Set up TAP interface
348 void inittap(void)
349 {
350 struct ifreq ifr;
351 struct sockaddr_in sin = {0};
352 memset(&ifr, 0, sizeof(ifr));
353 ifr.ifr_flags = IFF_TUN;
354
355 tapfd = open(TAPDEVICE, O_RDWR);
356 if (tapfd < 0)
357 { // fatal
358 log(0, 0, 0, 0, "Can't open %s: %s\n", TAPDEVICE, strerror(errno));
359 exit(1);
360 }
361 {
362 int flags = fcntl(tapfd, F_GETFL, 0);
363 fcntl(tapfd, F_SETFL, flags | O_NONBLOCK);
364 }
365 if (ioctl(tapfd, TUNSETIFF, (void *) &ifr) < 0)
366 {
367 log(0, 0, 0, 0, "Can't set tap interface: %s\n", strerror(errno));
368 exit(1);
369 }
370 assert(strlen(ifr.ifr_name) < sizeof(config->tapdevice));
371 strncpy(config->tapdevice, ifr.ifr_name, sizeof(config->tapdevice) - 1);
372 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
373
374 sin.sin_family = AF_INET;
375 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
376 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
377
378 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
379 {
380 log(0, 0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
381 exit(1);
382 }
383 /* Bump up the qlen to deal with bursts from the network */
384 ifr.ifr_qlen = 1000;
385 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
386 {
387 log(0, 0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
388 exit(1);
389 }
390 ifr.ifr_flags = IFF_UP;
391 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
392 {
393 log(0, 0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
394 exit(1);
395 }
396 if (ioctl(ifrfd, SIOCGIFHWADDR, (void *) &ifr) < 0)
397 {
398 log(0, 0, 0, 0, "Error setting tun hardware address: %s\n", strerror(errno));
399 exit(1);
400 }
401 memcpy(&tapmac, 2 + (u8 *) & ifr.ifr_hwaddr, 6);
402 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
403 {
404 log(0, 0, 0, 0, "Error setting tun ifindex: %s\n", strerror(errno));
405 exit(1);
406 }
407 tapidx = ifr.ifr_ifindex;
408 }
409
410 // set up UDP port
411 void initudp(void)
412 {
413 int on = 1;
414 struct sockaddr_in addr;
415
416 // Tunnel
417 memset(&addr, 0, sizeof(addr));
418 addr.sin_family = AF_INET;
419 addr.sin_port = htons(L2TPPORT);
420 addr.sin_addr.s_addr = config->bind_address;
421 udpfd = socket(AF_INET, SOCK_DGRAM, UDP);
422 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
423 {
424 int flags = fcntl(udpfd, F_GETFL, 0);
425 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
426 }
427 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
428 {
429 log(0, 0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
430 exit(1);
431 }
432 snoopfd = socket(AF_INET, SOCK_DGRAM, UDP);
433 snoop_addr.sin_family = AF_INET;
434
435 // Control
436 memset(&addr, 0, sizeof(addr));
437 addr.sin_family = AF_INET;
438 addr.sin_port = htons(1702);
439 controlfd = socket(AF_INET, SOCK_DGRAM, 17);
440 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
441 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
442 {
443 log(0, 0, 0, 0, "Error in control bind: %s\n", strerror(errno));
444 exit(1);
445 }
446 }
447
448 //
449 // Find session by IP, < 1 for not found
450 //
451 // Confusingly enough, this 'ip' must be
452 // in _network_ order. This being the common
453 // case when looking it up from IP packet headers.
454 //
455 // We actually use this cache for two things.
456 // #1. For used IP addresses, this maps to the
457 // session ID that it's used by.
458 // #2. For un-used IP addresses, this maps to the
459 // index into the pool table that contains that
460 // IP address.
461 //
462
463 int lookup_ipmap(ipt ip)
464 {
465 u8 *a = (u8 *)&ip;
466 char **d = (char **) ip_hash;
467 int s;
468
469 if (!(d = (char **) d[(size_t) *a++])) return 0;
470 if (!(d = (char **) d[(size_t) *a++])) return 0;
471 if (!(d = (char **) d[(size_t) *a++])) return 0;
472
473 s = (ipt) d[(size_t) *a];
474 return s;
475 }
476
477 sessionidt sessionbyip(ipt ip)
478 {
479 int s = lookup_ipmap(ip);
480 CSTAT(call_sessionbyip);
481
482 if (s > 0 && s < MAXSESSION && session[s].tunnel)
483 return s;
484 return 0;
485 }
486
487 //
488 // Take an IP address in HOST byte order and
489 // add it to the sessionid by IP cache.
490 //
491 // (It's actually cached in network order)
492 //
493 static void cache_ipmap(ipt ip, int s)
494 {
495 ipt nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char*)(&ip))[0]
496 u8 *a = (u8 *) &nip;
497 char **d = (char **) ip_hash;
498 int i;
499
500 for (i = 0; i < 3; i++)
501 {
502 if (!d[(size_t) a[i]])
503 {
504 if (!(d[(size_t) a[i]] = calloc(256, sizeof (void *))))
505 return;
506 }
507
508 d = (char **) d[(size_t) a[i]];
509 }
510
511 d[(size_t) a[3]] = (char *)((int)s);
512
513 if (s > 0)
514 log(4, ip, s, session[s].tunnel, "Caching ip address %s\n", inet_toa(nip));
515 else if (s == 0)
516 log(4, ip, 0, 0, "Un-caching ip address %s\n", inet_toa(nip));
517 // else a map to an ip pool index.
518 }
519
520 static void uncache_ipmap(ipt ip)
521 {
522 cache_ipmap(ip, 0); // Assign it to the NULL session.
523 }
524
525 //
526 // CLI list to dump current ipcache.
527 //
528 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
529 {
530 char **d = (char **) ip_hash, **e, **f, **g;
531 int i, j, k, l;
532 int count = 0;
533
534 if (CLI_HELP_REQUESTED)
535 return CLI_HELP_NO_ARGS;
536
537 cli_print(cli, "%7s %s", "Sess#", "IP Address");
538
539 for (i = 0; i < 256; ++i) {
540 if (!d[i]) continue;
541 e = (char**) d[i];
542 for (j = 0; j < 256; ++j) {
543 if (!e[j]) continue;
544 f = (char**) e[j];
545 for (k = 0; k < 256; ++k) {
546 if (!f[k]) continue;
547 g = (char**)f[k];
548 for (l = 0; l < 256; ++l) {
549 if (!g[l]) continue;
550 cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
551 ++count;
552 }
553 }
554 }
555 }
556 cli_print(cli, "%d entries in cache", count);
557 return CLI_OK;
558 }
559
560
561 // Find session by username, 0 for not found
562 // walled garden users aren't authenticated, so the username is
563 // reasonably useless. Ignore them to avoid incorrect actions
564 //
565 // This is VERY inefficent. Don't call it often. :)
566 //
567 sessionidt sessionbyuser(char *username)
568 {
569 int s;
570 CSTAT(call_sessionbyuser);
571
572 for (s = 1; s < MAXSESSION ; ++s) {
573 if (session[s].walled_garden)
574 continue; // Skip walled garden users.
575
576 if (!strncmp(session[s].user, username, 128))
577 return s;
578
579 }
580 return 0; // Not found.
581 }
582
583 void send_garp(ipt ip)
584 {
585 int s;
586 struct ifreq ifr;
587 u8 mac[6];
588
589 s = socket(PF_INET, SOCK_DGRAM, 0);
590 if (s < 0)
591 {
592 log(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
593 return;
594 }
595 memset(&ifr, 0, sizeof(ifr));
596 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
597 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
598 {
599 log(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
600 close(s);
601 return;
602 }
603 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
604 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
605 {
606 log(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
607 close(s);
608 return;
609 }
610 close(s);
611 sendarp(ifr.ifr_ifindex, mac, ip);
612 }
613
614 // Find session by username, 0 for not found
615 sessiont *sessiontbysessionidt(sessionidt s)
616 {
617 if (!s || s > MAXSESSION) return NULL;
618 return &session[s];
619 }
620
621 sessionidt sessionidtbysessiont(sessiont *s)
622 {
623 sessionidt val = s-session;
624 if (s < session || val > MAXSESSION) return 0;
625 return val;
626 }
627
628 // Handle ARP requests
629 void processarp(u8 * buf, int len)
630 {
631 ipt ip;
632 sessionidt s;
633
634 CSTAT(call_processarp);
635 STAT(arp_recv);
636
637 if (len != 46)
638 {
639 log(0, 0, 0, 0, "Unexpected length ARP %d bytes\n", len);
640 STAT(arp_errors);
641 return;
642 }
643 if (*(u16 *) (buf + 16) != htons(PKTARP))
644 {
645 log(0, 0, 0, 0, "Unexpected ARP type %04X\n", ntohs(*(u16 *) (buf + 16)));
646 STAT(arp_errors);
647 return;
648 }
649 if (*(u16 *) (buf + 18) != htons(0x0001))
650 {
651 log(0, 0, 0, 0, "Unexpected ARP hard type %04X\n", ntohs(*(u16 *) (buf + 18)));
652 STAT(arp_errors);
653 return;
654 }
655 if (*(u16 *) (buf + 20) != htons(PKTIP))
656 {
657 log(0, 0, 0, 0, "Unexpected ARP prot type %04X\n", ntohs(*(u16 *) (buf + 20)));
658 STAT(arp_errors);
659 return;
660 }
661 if (buf[22] != 6)
662 {
663 log(0, 0, 0, 0, "Unexpected ARP hard len %d\n", buf[22]);
664 STAT(arp_errors);
665 return;
666 }
667 if (buf[23] != 4)
668 {
669 log(0, 0, 0, 0, "Unexpected ARP prot len %d\n", buf[23]);
670 STAT(arp_errors);
671 return;
672 }
673 if (*(u16 *) (buf + 24) != htons(0x0001))
674 {
675 log(0, 0, 0, 0, "Unexpected ARP op %04X\n", ntohs(*(u16 *) (buf + 24)));
676 STAT(arp_errors);
677 return;
678 }
679 ip = *(u32 *) (buf + 42);
680 // look up session
681 s = sessionbyip(ip);
682 if (s)
683 {
684 log(3, ntohl(ip), s, session[s].tunnel, "ARP reply for %s\n", inet_toa(ip));
685 memcpy(buf + 4, buf + 10, 6); // set destination as source
686 *(u16 *) (buf + 10) = htons(tapmac[0]); // set source address
687 *(u16 *) (buf + 12) = htons(tapmac[1]);
688 *(u16 *) (buf + 14) = htons(tapmac[2]);
689 *(u16 *) (buf + 24) = htons(0x0002); // ARP reply
690 memcpy(buf + 26, buf + 10, 6); // sender ethernet
691 memcpy(buf + 36, buf + 4, 6); // target ethernet
692 *(u32 *) (buf + 42) = *(u32 *) (buf + 32); // target IP
693 *(u32 *) (buf + 32) = ip; // sender IP
694 write(tapfd, buf, len);
695 STAT(arp_replies);
696 }
697 else
698 {
699 log(3, ntohl(ip), 0, 0, "ARP request for unknown IP %s\n", inet_toa(ip));
700 STAT(arp_discarded);
701 }
702 }
703
704 // actually send a control message for a specific tunnel
705 void tunnelsend(u8 * buf, u16 l, tunnelidt t)
706 {
707 struct sockaddr_in addr;
708
709 CSTAT(call_tunnelsend);
710
711 if (!t)
712 {
713 static int backtrace_count = 0;
714 log(0, 0, 0, t, "tunnelsend called with 0 as tunnel id\n");
715 STAT(tunnel_tx_errors);
716 log_backtrace(backtrace_count, 5)
717 return;
718 }
719
720 if (!tunnel[t].ip)
721 {
722 static int backtrace_count = 0;
723 log(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
724 log_backtrace(backtrace_count, 5)
725 STAT(tunnel_tx_errors);
726 return;
727 }
728 memset(&addr, 0, sizeof(addr));
729 addr.sin_family = AF_INET;
730 *(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
731 addr.sin_port = htons(tunnel[t].port);
732
733 // sequence expected, if sequence in message
734 if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
735
736 // If this is a control message, deal with retries
737 if (*buf & 0x80)
738 {
739 tunnel[t].last = time_now; // control message sent
740 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
741 if (tunnel[t].try > 1)
742 {
743 STAT(tunnel_retries);
744 log(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
745 }
746 }
747
748 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
749 {
750 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",
751 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
752 STAT(tunnel_tx_errors);
753 return;
754 }
755
756 log_hex(5, "Send Tunnel Data", buf, l);
757 STAT(tunnel_tx_packets);
758 INC_STAT(tunnel_tx_bytes, l);
759 }
760
761 //
762 // Tiny helper function to write data to
763 // the 'tun' device.
764 //
765 int tun_write(u8 * data, int size)
766 {
767 return write(tapfd, data, size);
768 }
769
770 // process outgoing (to tunnel) IP
771 //
772 void processipout(u8 * buf, int len)
773 {
774 sessionidt s;
775 sessiont *sp;
776 tunnelidt t;
777 ipt ip;
778
779 char * data = buf; // Keep a copy of the originals.
780 int size = len;
781
782 u8 b[MAXETHER + 20];
783
784 CSTAT(call_processipout);
785
786 if (len < MIN_IP_SIZE)
787 {
788 log(1, 0, 0, 0, "Short IP, %d bytes\n", len);
789 STAT(tunnel_tx_errors);
790 return;
791 }
792 if (len >= MAXETHER)
793 {
794 log(1, 0, 0, 0, "Oversize IP packet %d bytes\n", len);
795 STAT(tunnel_tx_errors);
796 return;
797 }
798
799 // Skip the tun header
800 buf += 4;
801 len -= 4;
802
803 // Got an IP header now
804 if (*(u8 *)(buf) >> 4 != 4)
805 {
806 log(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
807 return;
808 }
809
810 ip = *(u32 *)(buf + 16);
811 if (!(s = sessionbyip(ip)))
812 {
813 // Is this a packet for a session that doesn't exist?
814 static int rate = 0; // Number of ICMP packets we've sent this second.
815 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
816
817 if (last != time_now) {
818 last = time_now;
819 rate = 0;
820 }
821
822 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
823 {
824 log(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
825 host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
826 }
827 return;
828 }
829 t = session[s].tunnel;
830 sp = &session[s];
831
832 if (sp->tbf_out)
833 {
834 // Are we throttling this session?
835 if (config->cluster_iam_master)
836 tbf_queue_packet(sp->tbf_out, data, size);
837 else
838 master_throttle_packet(sp->tbf_out, data, size);
839 return;
840 }
841 else if (sp->walled_garden && !config->cluster_iam_master)
842 {
843 // We are walled-gardening this
844 master_garden_packet(s, data, size);
845 return;
846 }
847
848 // Snooping this session, send it to intercept box
849 if (sp->snoop_ip && sp->snoop_port)
850 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
851
852 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
853
854 // Add on L2TP header
855 {
856 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
857 if (!p) {
858 log(3, session[s].ip, s, t, "failed to send packet in processipout.\n");
859 return;
860 }
861 tunnelsend(b, len + (p-b), t); // send it...
862 }
863
864 sp->cout += len; // byte count
865 sp->total_cout += len; // byte count
866 sp->pout++;
867 udp_tx += len;
868 sess_count[s].cout += len; // To send to master..
869 }
870
871 //
872 // Helper routine for the TBF filters.
873 // Used to send queued data in to the user!
874 //
875 void send_ipout(sessionidt s, u8 *buf, int len)
876 {
877 sessiont *sp;
878 tunnelidt t;
879 ipt ip;
880
881 u8 b[MAXETHER + 20];
882
883 if (len < 0 || len > MAXETHER) {
884 log(1,0,0,0, "Odd size IP packet: %d bytes\n", len);
885 return;
886 }
887
888 // Skip the tun header
889 buf += 4;
890 len -= 4;
891
892 ip = *(u32 *)(buf + 16);
893
894 if (!session[s].ip)
895 return;
896 t = session[s].tunnel;
897 sp = &session[s];
898
899 // Snooping this session, send it to intercept box
900 if (sp->snoop_ip && sp->snoop_port)
901 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
902
903 log(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
904
905 // Add on L2TP header
906 {
907 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
908 if (!p) {
909 log(3, session[s].ip, s, t, "failed to send packet in send_ipout.\n");
910 return;
911 }
912 tunnelsend(b, len + (p-b), t); // send it...
913 }
914 sp->cout += len; // byte count
915 sp->total_cout += len; // byte count
916 sp->pout++;
917 udp_tx += len;
918 sess_count[s].cout += len; // To send to master..
919 }
920
921 // add an AVP (16 bit)
922 void control16(controlt * c, u16 avp, u16 val, u8 m)
923 {
924 u16 l = (m ? 0x8008 : 0x0008);
925 *(u16 *) (c->buf + c->length + 0) = htons(l);
926 *(u16 *) (c->buf + c->length + 2) = htons(0);
927 *(u16 *) (c->buf + c->length + 4) = htons(avp);
928 *(u16 *) (c->buf + c->length + 6) = htons(val);
929 c->length += 8;
930 }
931
932 // add an AVP (32 bit)
933 void control32(controlt * c, u16 avp, u32 val, u8 m)
934 {
935 u16 l = (m ? 0x800A : 0x000A);
936 *(u16 *) (c->buf + c->length + 0) = htons(l);
937 *(u16 *) (c->buf + c->length + 2) = htons(0);
938 *(u16 *) (c->buf + c->length + 4) = htons(avp);
939 *(u32 *) (c->buf + c->length + 6) = htonl(val);
940 c->length += 10;
941 }
942
943 // add an AVP (32 bit)
944 void controls(controlt * c, u16 avp, char *val, u8 m)
945 {
946 u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
947 *(u16 *) (c->buf + c->length + 0) = htons(l);
948 *(u16 *) (c->buf + c->length + 2) = htons(0);
949 *(u16 *) (c->buf + c->length + 4) = htons(avp);
950 memcpy(c->buf + c->length + 6, val, strlen(val));
951 c->length += 6 + strlen(val);
952 }
953
954 // add a binary AVP
955 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
956 {
957 u16 l = ((m ? 0x8000 : 0) + len + 6);
958 *(u16 *) (c->buf + c->length + 0) = htons(l);
959 *(u16 *) (c->buf + c->length + 2) = htons(0);
960 *(u16 *) (c->buf + c->length + 4) = htons(avp);
961 memcpy(c->buf + c->length + 6, val, len);
962 c->length += 6 + len;
963 }
964
965 // new control connection
966 controlt *controlnew(u16 mtype)
967 {
968 controlt *c;
969 if (!controlfree)
970 c = malloc(sizeof(controlt));
971 else
972 {
973 c = controlfree;
974 controlfree = c->next;
975 }
976 assert(c);
977 c->next = 0;
978 *(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
979 c->length = 12;
980 control16(c, 0, mtype, 1);
981 return c;
982 }
983
984 // send zero block if nothing is waiting
985 // (ZLB send).
986 void controlnull(tunnelidt t)
987 {
988 u8 buf[12];
989 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
990 return;
991
992 *(u16 *) (buf + 0) = htons(0xC802); // flags/ver
993 *(u16 *) (buf + 2) = htons(12); // length
994 *(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
995 *(u16 *) (buf + 6) = htons(0); // session
996 *(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
997 *(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
998 tunnelsend(buf, 12, t);
999 }
1000
1001 // add a control message to a tunnel, and send if within window
1002 void controladd(controlt * c, tunnelidt t, sessionidt s)
1003 {
1004 *(u16 *) (c->buf + 2) = htons(c->length); // length
1005 *(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1006 *(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
1007 *(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1008 tunnel[t].ns++; // advance sequence
1009 // link in message in to queue
1010 if (tunnel[t].controlc)
1011 tunnel[t].controle->next = c;
1012 else
1013 tunnel[t].controls = c;
1014 tunnel[t].controle = c;
1015 tunnel[t].controlc++;
1016 // send now if space in window
1017 if (tunnel[t].controlc <= tunnel[t].window)
1018 {
1019 tunnel[t].try = 0; // first send
1020 tunnelsend(c->buf, c->length, t);
1021 }
1022 }
1023
1024 //
1025 // Throttle or Unthrottle a session
1026 //
1027 // Throttle the data folling through a session
1028 // to be no more than 'throttle' kbit/sec each way.
1029 //
1030 int throttle_session(sessionidt s, int throttle)
1031 {
1032 if (!session[s].tunnel)
1033 return 0; // No-one home.
1034
1035 if (!*session[s].user)
1036 return 0; // User not logged in
1037
1038 if (throttle) {
1039 if (session[s].tbf_in || session[s].tbf_out) {
1040 if (throttle == session[s].throttle)
1041 return 1;
1042
1043 // Currently throttled but the rate is changing.
1044
1045 free_tbf(session[s].tbf_in);
1046 free_tbf(session[s].tbf_out);
1047 }
1048
1049 session[s].tbf_in = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipin);
1050 session[s].tbf_out = new_tbf(s, throttle*1024/4, throttle*1024/8, send_ipout);
1051
1052 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
1053 session[s].throttle = throttle;
1054 cluster_send_session(s);
1055 }
1056
1057 return 1;
1058 }
1059
1060 // else Unthrottling.
1061
1062 if (!session[s].tbf_in && !session[s].tbf_out && !session[s].throttle)
1063 return 0;
1064
1065 free_tbf(session[s].tbf_in);
1066 session[s].tbf_in = 0;
1067
1068 free_tbf(session[s].tbf_out);
1069 session[s].tbf_out = 0;
1070
1071 if (throttle != session[s].throttle) { // Changed. Flood to slaves.
1072 session[s].throttle = throttle;
1073 cluster_send_session(s);
1074 }
1075
1076 return 0;
1077 }
1078
1079 // start tidy shutdown of session
1080 void sessionshutdown(sessionidt s, char *reason)
1081 {
1082 int dead = session[s].die;
1083 int walled_garden = session[s].walled_garden;
1084
1085
1086 CSTAT(call_sessionshutdown);
1087
1088 if (!session[s].tunnel)
1089 {
1090 log(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1091 return; // not a live session
1092 }
1093
1094 if (!session[s].die)
1095 log(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1096
1097 session[s].die = now() + 150; // Clean up in 15 seconds
1098
1099 {
1100 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1101 run_plugins(PLUGIN_KILL_SESSION, &data);
1102 }
1103
1104 // RADIUS Stop message
1105 if (session[s].opened && !walled_garden && !dead) {
1106 u16 r = session[s].radius;
1107 if (!r)
1108 {
1109 if (!(r = radiusnew(s)))
1110 {
1111 log(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1112 STAT(radius_overflow);
1113 }
1114 else
1115 {
1116 int n;
1117 for (n = 0; n < 15; n++)
1118 radius[r].auth[n] = rand();
1119 }
1120 }
1121 if (r && radius[r].state != RADIUSSTOP)
1122 radiussend(r, RADIUSSTOP); // stop, if not already trying
1123 }
1124
1125 if (session[s].ip)
1126 { // IP allocated, clear and unroute
1127 int r;
1128 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1129 {
1130 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 0);
1131 session[s].route[r].ip = 0;
1132 }
1133
1134 if (session[s].ip_pool_index == -1) // static ip
1135 {
1136 routeset(s, session[s].ip, 0, 0, 0); // Delete route.
1137 session[s].ip = 0;
1138 }
1139 else
1140 free_ip_address(s);
1141
1142 if (session[s].throttle) // Unthrottle if throttled.
1143 throttle_session(s, 0);
1144 }
1145 { // Send CDN
1146 controlt *c = controlnew(14); // sending CDN
1147 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1148 control16(c, 14, s, 1); // assigned session (our end)
1149 controladd(c, session[s].tunnel, s); // send the message
1150 }
1151 cluster_send_session(s);
1152 }
1153
1154 void sendipcp(tunnelidt t, sessionidt s)
1155 {
1156 u8 buf[MAXCONTROL];
1157 u16 r = session[s].radius;
1158 u8 *q;
1159
1160 CSTAT(call_sendipcp);
1161
1162 if (!r)
1163 r = radiusnew(s);
1164 if (radius[r].state != RADIUSIPCP)
1165 {
1166 radius[r].state = RADIUSIPCP;
1167 radius[r].try = 0;
1168 }
1169 radius[r].retry = backoff(radius[r].try++);
1170 if (radius[r].try > 10)
1171 {
1172 sessionshutdown(s, "No reply on IPCP");
1173 return;
1174 }
1175
1176 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1177 if (!q) {
1178 log(3, session[s].ip, s, t, "failed to send packet in sendipcp.\n");
1179 return;
1180 }
1181
1182 *q = ConfigReq;
1183 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1184 *(u16 *) (q + 2) = htons(10);
1185 q[4] = 3;
1186 q[5] = 6;
1187 *(u32 *) (q + 6) = config->bind_address; // send my IP
1188 tunnelsend(buf, 10 + (q - buf), t); // send it
1189 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1190 }
1191
1192 // kill a session now
1193 void sessionkill(sessionidt s, char *reason)
1194 {
1195
1196 CSTAT(call_sessionkill);
1197
1198 sessionshutdown(s, reason); // close radius/routes, etc.
1199 if (session[s].radius)
1200 radiusclear(session[s].radius, 0); // cant send clean accounting data, session is killed
1201 log(2, 0, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1202
1203 throttle_session(s, 0); // Force session to be un-throttle. Free'ing TBF structures.
1204
1205 memset(&session[s], 0, sizeof(session[s]));
1206 session[s].tunnel = T_FREE; // Mark it as free.
1207 session[s].next = sessionfree;
1208 sessionfree = s;
1209 cluster_send_session(s);
1210 }
1211
1212 // kill a tunnel now
1213 void tunnelkill(tunnelidt t, char *reason)
1214 {
1215 sessionidt s;
1216 controlt *c;
1217
1218 CSTAT(call_tunnelkill);
1219
1220 tunnel[t].state = TUNNELDIE;
1221
1222 // free control messages
1223 while ((c = tunnel[t].controls))
1224 {
1225 controlt * n = c->next;
1226 tunnel[t].controls = n;
1227 tunnel[t].controlc--;
1228 c->next = controlfree;
1229 controlfree = c;
1230 }
1231 // kill sessions
1232 for (s = 1; s < MAXSESSION; s++)
1233 if (session[s].tunnel == t)
1234 sessionkill(s, reason);
1235
1236 // free tunnel
1237 tunnelclear(t);
1238 cluster_send_tunnel(t);
1239 log(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
1240 tunnel[t].die = 0;
1241 tunnel[t].state = TUNNELFREE;
1242 }
1243
1244 // shut down a tunnel cleanly
1245 void tunnelshutdown(tunnelidt t, char *reason)
1246 {
1247 sessionidt s;
1248
1249 CSTAT(call_tunnelshutdown);
1250
1251 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1252 {
1253 // never set up, can immediately kill
1254 tunnelkill(t, reason);
1255 return;
1256 }
1257 log(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1258
1259 // close session
1260 for (s = 1; s < MAXSESSION; s++)
1261 if (session[s].tunnel == t)
1262 sessionkill(s, reason);
1263
1264 tunnel[t].state = TUNNELDIE;
1265 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1266 cluster_send_tunnel(t);
1267 // TBA - should we wait for sessions to stop?
1268 { // Send StopCCN
1269 controlt *c = controlnew(4); // sending StopCCN
1270 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message
1271 control16(c, 9, t, 1); // assigned tunnel (our end)
1272 controladd(c, t, 0); // send the message
1273 }
1274 }
1275
1276 // read and process packet on tunnel (UDP)
1277 void processudp(u8 * buf, int len, struct sockaddr_in *addr)
1278 {
1279 char *chapresponse = NULL;
1280 u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
1281 u8 *p = buf + 2;
1282
1283
1284 CSTAT(call_processudp);
1285
1286 udp_rx += len;
1287 udp_rx_pkt++;
1288 log_hex(5, "UDP Data", buf, len);
1289 STAT(tunnel_rx_packets);
1290 INC_STAT(tunnel_rx_bytes, len);
1291 if (len < 6)
1292 {
1293 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
1294 STAT(tunnel_rx_errors);
1295 return;
1296 }
1297 if ((buf[1] & 0x0F) != 2)
1298 {
1299 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1300 STAT(tunnel_rx_errors);
1301 return;
1302 }
1303 if (*buf & 0x40)
1304 { // length
1305 l = ntohs(*(u16 *) p);
1306 p += 2;
1307 }
1308 t = ntohs(*(u16 *) p);
1309 p += 2;
1310 s = ntohs(*(u16 *) p);
1311 p += 2;
1312 if (s >= MAXSESSION)
1313 {
1314 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
1315 STAT(tunnel_rx_errors);
1316 return;
1317 }
1318 if (t >= MAXTUNNEL)
1319 {
1320 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
1321 STAT(tunnel_rx_errors);
1322 return;
1323 }
1324 if (*buf & 0x08)
1325 { // ns/nr
1326 ns = ntohs(*(u16 *) p);
1327 p += 2;
1328 nr = ntohs(*(u16 *) p);
1329 p += 2;
1330 }
1331 if (*buf & 0x02)
1332 { // offset
1333 u16 o = ntohs(*(u16 *) p);
1334 p += o + 2;
1335 }
1336 if ((p - buf) > l)
1337 {
1338 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
1339 STAT(tunnel_rx_errors);
1340 return;
1341 }
1342 l -= (p - buf);
1343 if (*buf & 0x80)
1344 { // control
1345 u16 message = 0xFFFF; // message type
1346 u8 fatal = 0;
1347 u8 mandatorymessage = 0;
1348 u8 chap = 0; // if CHAP being used
1349 u16 asession = 0; // assigned session
1350 u32 amagic = 0; // magic number
1351 u8 aflags = 0; // flags from last LCF
1352 u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1353 int requestchap = 0; // do we request PAP instead of original CHAP request?
1354 char called[MAXTEL] = ""; // called number
1355 char calling[MAXTEL] = ""; // calling number
1356
1357 if (!config->cluster_iam_master) {
1358 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1359 return;
1360 }
1361
1362 if ((*buf & 0xCA) != 0xC8)
1363 {
1364 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
1365 STAT(tunnel_rx_errors);
1366 return;
1367 }
1368 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",
1369 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1370 // if no tunnel specified, assign one
1371 if (!t)
1372 {
1373 int i;
1374
1375 //
1376 // Is this a duplicate of the first packet? (SCCRQ)
1377 //
1378 for ( i = 1; i <= config->cluster_highest_tunnelid ; ++i) {
1379 if (tunnel[t].state != TUNNELOPENING ||
1380 tunnel[t].ip != ntohl(*(ipt *) & addr->sin_addr) ||
1381 tunnel[t].port != ntohs(addr->sin_port) )
1382 continue;
1383 t = i;
1384 break;
1385 }
1386 }
1387
1388 if (!t) {
1389 if (!(t = new_tunnel()))
1390 {
1391 log(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
1392 STAT(tunnel_overflow);
1393 return;
1394 }
1395 tunnelclear(t);
1396 tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
1397 tunnel[t].port = ntohs(addr->sin_port);
1398 tunnel[t].window = 4; // default window
1399 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);
1400 STAT(tunnel_created);
1401 }
1402
1403 // This is used to time out old tunnels
1404 tunnel[t].lastrec = time_now;
1405
1406 // check sequence of this message
1407 {
1408 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1409 // some to clear maybe?
1410 while (tunnel[t].controlc && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1411 {
1412 controlt *c = tunnel[t].controls;
1413 tunnel[t].controls = c->next;
1414 tunnel[t].controlc--;
1415 c->next = controlfree;
1416 controlfree = c;
1417 skip--;
1418 tunnel[t].try = 0; // we have progress
1419 }
1420
1421 // If the 'ns' just received is not the 'nr' we're
1422 // expecting, just send an ack and drop it.
1423 //
1424 // if 'ns' is less, then we got a retransmitted packet.
1425 // if 'ns' is greater than missed a packet. Either way
1426 // we should ignore it.
1427 if (ns != tunnel[t].nr)
1428 {
1429 // is this the sequence we were expecting?
1430 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);
1431 STAT(tunnel_rx_errors);
1432
1433 if (l) // Is this not a ZLB?
1434 controlnull(t);
1435 return;
1436 }
1437 // receiver advance (do here so quoted correctly in any sends below)
1438 if (l) tunnel[t].nr = (ns + 1);
1439 if (skip < 0) skip = 0;
1440 if (skip < tunnel[t].controlc)
1441 {
1442 // some control packets can now be sent that were previous stuck out of window
1443 int tosend = tunnel[t].window - skip;
1444 controlt *c = tunnel[t].controls;
1445 while (c && skip)
1446 {
1447 c = c->next;
1448 skip--;
1449 }
1450 while (c && tosend)
1451 {
1452 tunnel[t].try = 0; // first send
1453 tunnelsend(c->buf, c->length, t);
1454 c = c->next;
1455 tosend--;
1456 }
1457 }
1458 if (!tunnel[t].controlc)
1459 tunnel[t].retry = 0; // caught up
1460 }
1461 if (l)
1462 { // if not a null message
1463 // process AVPs
1464 while (l && !(fatal & 0x80))
1465 {
1466 u16 n = (ntohs(*(u16 *) p) & 0x3FF);
1467 u8 *b = p;
1468 u8 flags = *p;
1469 u16 mtype;
1470 p += n; // next
1471 if (l < n)
1472 {
1473 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
1474 STAT(tunnel_rx_errors);
1475 fatal = flags;
1476 return;
1477 }
1478 l -= n;
1479 if (flags & 0x40)
1480 {
1481 // handle hidden AVPs
1482 if (!*config->l2tpsecret)
1483 {
1484 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
1485 fatal = flags;
1486 continue;
1487 }
1488 if (!session[s].random_vector_length)
1489 {
1490 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
1491 fatal = flags;
1492 continue;
1493 }
1494 log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
1495 }
1496 if (*b & 0x3C)
1497 {
1498 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
1499 fatal = flags;
1500 continue; // next
1501 }
1502 b += 2;
1503 if (*(u16 *) (b))
1504 {
1505 log(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
1506 fatal = flags;
1507 continue; // next
1508 }
1509 b += 2;
1510 mtype = ntohs(*(u16 *) (b));
1511 b += 2;
1512 n -= 6;
1513
1514 log(4, ntohl(addr->sin_addr.s_addr), s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1515 switch (mtype)
1516 {
1517 case 0: // message type
1518 message = ntohs(*(u16 *) b);
1519 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Message type = %d (%s)\n", *b,
1520 l2tp_message_types[message]);
1521 mandatorymessage = flags;
1522 break;
1523 case 1: // result code
1524 {
1525 u16 rescode = ntohs(*(u16 *)(b));
1526 const char* resdesc = "(unknown)";
1527 if (message == 4) { /* StopCCN */
1528 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1529 resdesc = stopccn_result_codes[rescode];
1530 } else if (message == 14) { /* CDN */
1531 if (rescode <= MAX_CDN_RESULT_CODE)
1532 resdesc = cdn_result_codes[rescode];
1533 }
1534
1535 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Result Code %d: %s\n",
1536 rescode, resdesc);
1537 if (n >= 4) {
1538 u16 errcode = ntohs(*(u16 *)(b + 2));
1539 const char* errdesc = "(unknown)";
1540 if (errcode <= MAX_ERROR_CODE)
1541 errdesc = error_codes[errcode];
1542 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error Code %d: %s\n",
1543 errcode, errdesc);
1544 }
1545 if (n > 4) {
1546 /* %*s doesn't work?? */
1547 char *buf = (char *)strndup(b+4, n-4);
1548 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Error String: %s\n",
1549 buf);
1550 free(buf);
1551 }
1552 break;
1553 }
1554 break;
1555 case 2: // protocol version
1556 {
1557 version = ntohs(*(u16 *) (b));
1558 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Protocol version = %d\n", version);
1559 if (version && version != 0x0100)
1560 { // allow 0.0 and 1.0
1561 log(1, ntohl(addr->sin_addr.s_addr), s, t, " Bad protocol version %04X\n",
1562 version);
1563 fatal = flags;
1564 continue; // next
1565 }
1566 }
1567 break;
1568 case 3: // framing capabilities
1569 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
1570 break;
1571 case 4: // bearer capabilities
1572 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
1573 break;
1574 case 5: // tie breaker
1575 // We never open tunnels, so we don't care about tie breakers
1576 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
1577 continue;
1578 case 6: // firmware revision
1579 // log(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
1580 break;
1581 case 7: // host name
1582 memset(tunnel[t].hostname, 0, 128);
1583 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1584 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1585 // TBA - to send to RADIUS
1586 break;
1587 case 8: // vendor name
1588 memset(tunnel[t].vendor, 0, 128);
1589 memcpy(tunnel[t].vendor, b, (n >= 127) ? 127 : n);
1590 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1591 break;
1592 case 9: // assigned tunnel
1593 tunnel[t].far = ntohs(*(u16 *) (b));
1594 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1595 break;
1596 case 10: // rx window
1597 tunnel[t].window = ntohs(*(u16 *) (b));
1598 if (!tunnel[t].window)
1599 tunnel[t].window = 1; // window of 0 is silly
1600 log(4, ntohl(addr->sin_addr.s_addr), s, t, " rx window = %d\n", tunnel[t].window);
1601 break;
1602 case 11: // Challenge
1603 {
1604 log(4, ntohl(addr->sin_addr.s_addr), s, t, " LAC requested CHAP authentication for tunnel\n");
1605 build_chap_response(b, 2, n, &chapresponse);
1606 }
1607 break;
1608 case 14: // assigned session
1609 asession = session[s].far = ntohs(*(u16 *) (b));
1610 log(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
1611 break;
1612 case 15: // call serial number
1613 log(4, ntohl(addr->sin_addr.s_addr), s, t, " call serial number = %d\n", ntohl(*(u32 *)b));
1614 break;
1615 case 18: // bearer type
1616 log(4, ntohl(addr->sin_addr.s_addr), s, t, " bearer type = %d\n", ntohl(*(u32 *)b));
1617 // TBA - for RADIUS
1618 break;
1619 case 19: // framing type
1620 log(4, ntohl(addr->sin_addr.s_addr), s, t, " framing type = %d\n", ntohl(*(u32 *)b));
1621 // TBA
1622 break;
1623 case 21: // called number
1624 memset(called, 0, MAXTEL);
1625 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1626 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Called <%s>\n", called);
1627 break;
1628 case 22: // calling number
1629 memset(calling, 0, MAXTEL);
1630 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1631 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Calling <%s>\n", calling);
1632 break;
1633 case 24: // tx connect speed
1634 if (n == 4)
1635 {
1636 session[s].tx_connect_speed = ntohl(*(u32 *)b);
1637 }
1638 else
1639 {
1640 // AS5300s send connect speed as a string
1641 char tmp[30] = {0};
1642 memcpy(tmp, b, (n >= 30) ? 30 : n);
1643 session[s].tx_connect_speed = atol(tmp);
1644 }
1645 log(4, ntohl(addr->sin_addr.s_addr), s, t, " TX connect speed <%u>\n",
1646 session[s].tx_connect_speed);
1647 break;
1648 case 38: // rx connect speed
1649 if (n == 4)
1650 {
1651 session[s].rx_connect_speed = ntohl(*(u32 *)b);
1652 }
1653 else
1654 {
1655 // AS5300s send connect speed as a string
1656 char tmp[30] = {0};
1657 memcpy(tmp, b, (n >= 30) ? 30 : n);
1658 session[s].rx_connect_speed = atol(tmp);
1659 }
1660 log(4, ntohl(addr->sin_addr.s_addr), s, t, " RX connect speed <%u>\n",
1661 session[s].rx_connect_speed);
1662 break;
1663 case 25: // Physical Channel ID
1664 {
1665 u32 tmp = ntohl(*(u32 *)b);
1666 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Physical Channel ID <%X>\n", tmp);
1667 break;
1668 }
1669 case 29: // Proxy Authentication Type
1670 {
1671 u16 authtype = ntohs(*(u16 *)b);
1672 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Type %d (%s)\n",
1673 authtype, authtypes[authtype]);
1674 requestchap = (authtype == 2);
1675 break;
1676 }
1677 case 30: // Proxy Authentication Name
1678 {
1679 char authname[64] = {0};
1680 memcpy(authname, b, (n > 63) ? 63 : n);
1681 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Name (%s)\n",
1682 authname);
1683 break;
1684 }
1685 case 31: // Proxy Authentication Challenge
1686 {
1687 memcpy(radius[session[s].radius].auth, b, 16);
1688 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Challenge\n");
1689 break;
1690 }
1691 case 32: // Proxy Authentication ID
1692 {
1693 u16 authid = ntohs(*(u16 *)(b));
1694 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth ID (%d)\n",
1695 authid);
1696 if (session[s].radius)
1697 radius[session[s].radius].id = authid;
1698 break;
1699 }
1700 case 33: // Proxy Authentication Response
1701 {
1702 char authresp[64] = {0};
1703 memcpy(authresp, b, (n > 63) ? 63 : n);
1704 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Response\n");
1705 break;
1706 }
1707 case 27: // last send lcp
1708 { // find magic number
1709 u8 *p = b, *e = p + n;
1710 while (p < e && p[1])
1711 {
1712 if (*p == 5 && p[1] == 6)
1713 amagic = ntohl(*(u32 *) (p + 2));
1714 else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5)
1715 chap = 1;
1716 else if (*p == 7)
1717 aflags |= SESSIONPFC;
1718 else if (*p == 8)
1719 aflags |= SESSIONACFC;
1720 p += p[1];
1721 }
1722
1723 {
1724 char tmp[500] = {0};
1725 tmp[0] = ConfigReq;
1726 memcpy((tmp + 1), b, n);
1727 }
1728 }
1729 break;
1730 case 28: // last recv lcp confreq
1731 {
1732 char tmp[500] = {0};
1733 tmp[0] = ConfigReq;
1734 memcpy((tmp + 1), b, n);
1735 break;
1736 }
1737 case 26: // Initial Received LCP CONFREQ
1738 {
1739 char tmp[500] = {0};
1740 tmp[0] = ConfigReq;
1741 memcpy((tmp + 1), b, n);
1742 }
1743 break;
1744 case 39: // seq required - we control it as an LNS anyway...
1745 break;
1746 case 36: // Random Vector
1747 log(4, ntohl(addr->sin_addr.s_addr), s, t, " Random Vector received. Enabled AVP Hiding.\n");
1748 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1749 memcpy(session[s].random_vector, b, n);
1750 session[s].random_vector_length = n;
1751 break;
1752 default:
1753 log(2, ntohl(addr->sin_addr.s_addr), s, t, " Unknown AVP type %d\n", mtype);
1754 fatal = flags;
1755 continue; // next
1756 }
1757 }
1758 // process message
1759 if (fatal & 0x80)
1760 tunnelshutdown(t, "Unknown Mandatory AVP");
1761 else
1762 switch (message)
1763 {
1764 case 1: // SCCRQ - Start Control Connection Request
1765 {
1766 controlt *c = controlnew(2); // sending SCCRP
1767 control16(c, 2, version, 1); // protocol version
1768 control32(c, 3, 3, 1); // framing
1769 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1770 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1771 control16(c, 9, t, 1); // assigned tunnel
1772 controladd(c, t, s); // send the resply
1773 }
1774 tunnel[t].state = TUNNELOPENING;
1775 break;
1776 case 2: // SCCRP
1777 tunnel[t].state = TUNNELOPEN;
1778 break;
1779 case 3: // SCCN
1780 tunnel[t].state = TUNNELOPEN;
1781 controlnull(t); // ack
1782 break;
1783 case 4: // StopCCN
1784 controlnull(t); // ack
1785 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1786 tunnelkill(t, "Stopped"); // Immediately force everything dead
1787 break;
1788 case 6: // HELLO
1789 controlnull(t); // simply ACK
1790 break;
1791 case 7: // OCRQ
1792 // TBA
1793 break;
1794 case 8: // OCRO
1795 // TBA
1796 break;
1797 case 9: // OCCN
1798 // TBA
1799 break;
1800 case 10: // ICRQ
1801 if (!sessionfree)
1802 {
1803 STAT(session_overflow);
1804 tunnelshutdown(t, "No free sessions");
1805 }
1806 else
1807 {
1808 u16 r;
1809 controlt *c;
1810
1811 s = sessionfree;
1812 sessionfree = session[s].next;
1813 memset(&session[s], 0, sizeof(session[s]));
1814
1815 if (s > config->cluster_highest_sessionid)
1816 config->cluster_highest_sessionid = s;
1817
1818 // make a RADIUS session
1819 if (!(r = radiusnew(s)))
1820 {
1821 log(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
1822 // sessionkill(s, "no free RADIUS sesions");
1823 return;
1824 }
1825
1826 c = controlnew(11); // sending ICRP
1827 session[s].id = sessionid++;
1828 session[s].opened = time(NULL);
1829 session[s].tunnel = t;
1830 session[s].far = asession;
1831 session[s].last_packet = time_now;
1832 log(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1833 control16(c, 14, s, 1); // assigned session
1834 controladd(c, t, s); // send the reply
1835 {
1836 // Generate a random challenge
1837 int n;
1838 for (n = 0; n < 15; n++)
1839 radius[r].auth[n] = rand();
1840 }
1841 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1842 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1843 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1844 STAT(session_created);
1845 }
1846 break;
1847 case 11: // ICRP
1848 // TBA
1849 break;
1850 case 12: // ICCN
1851 session[s].magic = amagic; // set magic number
1852 session[s].l2tp_flags = aflags; // set flags received
1853 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
1854 controlnull(t); // ack
1855 // In CHAP state, request PAP instead
1856 if (requestchap)
1857 initlcp(t, s);
1858 break;
1859 case 14: // CDN
1860 controlnull(t); // ack
1861 sessionshutdown(s, "Closed (Received CDN)");
1862 break;
1863 case 0xFFFF:
1864 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
1865 break;
1866 default:
1867 STAT(tunnel_rx_errors);
1868 if (mandatorymessage & 0x80)
1869 tunnelshutdown(t, "Unknown message");
1870 else
1871 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
1872 break;
1873 }
1874 if (chapresponse) free(chapresponse);
1875 cluster_send_tunnel(t);
1876 }
1877 else
1878 {
1879 log(4, 0, s, t, " Got a ZLB ack\n");
1880 }
1881 }
1882 else
1883 { // data
1884 u16 prot;
1885
1886 log_hex(5, "Receive Tunnel Data", p, l);
1887 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1888 { // HDLC address header, discard
1889 p += 2;
1890 l -= 2;
1891 }
1892 if (l < 2)
1893 {
1894 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
1895 STAT(tunnel_rx_errors);
1896 return;
1897 }
1898 if (*p & 1)
1899 {
1900 prot = *p++;
1901 l--;
1902 }
1903 else
1904 {
1905 prot = ntohs(*(u16 *) p);
1906 p += 2;
1907 l -= 2;
1908 }
1909
1910 if (s && !session[s].tunnel) // Is something wrong??
1911 {
1912 if (!config->cluster_iam_master)
1913 {
1914 // Pass it off to the master to deal with..
1915 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1916 return;
1917 }
1918
1919
1920 log(1, ntohl(addr->sin_addr.s_addr), s, t, "UDP packet contains session %d "
1921 "but no session[%d].tunnel exists (LAC said"
1922 " tunnel = %d). Dropping packet.\n", s, s, t);
1923 STAT(tunnel_rx_errors);
1924 return;
1925 }
1926
1927 if (session[s].die)
1928 {
1929 log(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
1930 // I'm pretty sure this isn't right -- mo.
1931 // return; // closing session, PPP not processed
1932 }
1933 if (prot == PPPPAP)
1934 {
1935 session[s].last_packet = time_now;
1936 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1937 processpap(t, s, p, l);
1938 }
1939 else if (prot == PPPCHAP)
1940 {
1941 session[s].last_packet = time_now;
1942 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1943 processchap(t, s, p, l);
1944 }
1945 else if (prot == PPPLCP)
1946 {
1947 session[s].last_packet = time_now;
1948 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1949 processlcp(t, s, p, l);
1950 }
1951 else if (prot == PPPIPCP)
1952 {
1953 session[s].last_packet = time_now;
1954 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1955 processipcp(t, s, p, l);
1956 }
1957 else if (prot == PPPCCP)
1958 {
1959 session[s].last_packet = time_now;
1960 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1961 processccp(t, s, p, l);
1962 }
1963 else if (prot == PPPIP)
1964 {
1965 if (!config->cluster_iam_master)
1966 {
1967 // We're a slave. Should we forward this packet to the master?
1968
1969 // Is this a walled garden session, or something that needs it's
1970 // idle time updated??
1971
1972 // Maintain the idle timeouts on the master. If this would
1973 // significantly reset the idletimeout, run it via the master
1974 // to refresh the master's idle timer.
1975 // Not sure this is ideal: It may re-order packets.
1976
1977 if (session[s].walled_garden || (session[s].last_packet + (ECHO_TIMEOUT/2)) < time_now)
1978 {
1979 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1980 session[s].last_packet = time_now;
1981 return;
1982 }
1983 // fall through to processipin.
1984 } else
1985 session[s].last_packet = time_now;
1986 processipin(t, s, p, l);
1987 }
1988 else
1989 {
1990 STAT(tunnel_rx_errors);
1991 log(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
1992 }
1993 }
1994 }
1995
1996 // read and process packet on tap
1997 void processtap(u8 * buf, int len)
1998 {
1999 log_hex(5, "Receive TAP Data", buf, len);
2000 STAT(tap_rx_packets);
2001 INC_STAT(tap_rx_bytes, len);
2002
2003 CSTAT(call_processtap);
2004
2005 eth_rx_pkt++;
2006 eth_rx += len;
2007 if (len < 22)
2008 {
2009 log(1, 0, 0, 0, "Short tap packet %d bytes\n", len);
2010 STAT(tap_rx_errors);
2011 return;
2012 }
2013 if (*(u16 *) (buf + 2) == htons(PKTARP)) // ARP
2014 processarp(buf, len);
2015 else if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
2016 processipout(buf, len);
2017 // Else discard.
2018 }
2019
2020 //
2021 // Maximum number of actions to complete.
2022 // This is to avoid sending out too many packets
2023 // at once.
2024 #define MAX_ACTIONS 500
2025
2026 int regular_cleanups(void)
2027 {
2028 static sessionidt s = 0; // Next session to check for actions on.
2029 tunnelidt t;
2030 int count=0,i;
2031 u16 r;
2032 static clockt next_acct = 0;
2033
2034 log(3, 0, 0, 0, "Begin regular cleanup\n");
2035
2036 for (r = 1; r < MAXRADIUS; r++)
2037 {
2038 if (!radius[r].state)
2039 continue;
2040 if (radius[r].retry)
2041 {
2042 if (radius[r].retry <= TIME)
2043 radiusretry(r);
2044 } else
2045 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2046 }
2047 for (t = 1; t < config->cluster_highest_tunnelid; t++)
2048 {
2049 // check for expired tunnels
2050 if (tunnel[t].die && tunnel[t].die <= TIME)
2051 {
2052 STAT(tunnel_timeout);
2053 tunnelkill(t, "Expired");
2054 continue;
2055 }
2056 // check for message resend
2057 if (tunnel[t].retry && tunnel[t].controlc)
2058 {
2059 // resend pending messages as timeout on reply
2060 if (tunnel[t].retry <= TIME)
2061 {
2062 controlt *c = tunnel[t].controls;
2063 u8 w = tunnel[t].window;
2064 tunnel[t].try++; // another try
2065 if (tunnel[t].try > 5)
2066 tunnelkill(t, "Timeout on control message"); // game over
2067 else
2068 while (c && w--)
2069 {
2070 tunnelsend(c->buf, c->length, t);
2071 c = c->next;
2072 }
2073 }
2074 }
2075 // Send hello
2076 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2077 {
2078 controlt *c = controlnew(6); // sending HELLO
2079 controladd(c, t, 0); // send the message
2080 log(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
2081 }
2082 }
2083
2084 // Check for sessions that have been killed from the CLI
2085 if (cli_session_kill[0])
2086 {
2087 int i;
2088 for (i = 0; i < MAXSESSION && cli_session_kill[i]; i++)
2089 {
2090 log(2, 0, cli_session_kill[i], 0, "Dropping session by CLI\n");
2091 sessionshutdown(cli_session_kill[i], "Requested by administrator");
2092 cli_session_kill[i] = 0;
2093 }
2094 }
2095 // Check for tunnels that have been killed from the CLI
2096 if (cli_tunnel_kill[0])
2097 {
2098 int i;
2099 for (i = 1; i < MAXTUNNEL && cli_tunnel_kill[i]; i++)
2100 {
2101 log(2, 0, cli_tunnel_kill[i], 0, "Dropping tunnel by CLI\n");
2102 tunnelshutdown(cli_tunnel_kill[i], "Requested by administrator");
2103 cli_tunnel_kill[i] = 0;
2104 }
2105 }
2106
2107 count = 0;
2108 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2109 {
2110
2111 s++;
2112 if (s > config->cluster_highest_sessionid)
2113 s = 1;
2114
2115 if (!session[s].tunnel) // Session isn't in use
2116 continue;
2117
2118 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED) )
2119 {
2120 // IPCP has not completed yet. Resend
2121 log(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2122 sendipcp(session[s].tunnel, s);
2123 }
2124
2125 // check for expired sessions
2126 if (session[s].die && session[s].die <= TIME)
2127 {
2128 sessionkill(s, "Expired");
2129 if (++count >= MAX_ACTIONS) break;
2130 continue;
2131 }
2132
2133 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2134 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2135 {
2136 sessionkill(s, "No response to LCP ECHO requests");
2137 STAT(session_timeout);
2138 if (++count >= MAX_ACTIONS) break;
2139 continue;
2140 }
2141
2142 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2143 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2144 {
2145 u8 b[MAXCONTROL] = {0};
2146
2147 u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2148 if (!q) {
2149 log(3, session[s].ip, s, t, "failed to send ECHO packet.\n");
2150 continue;
2151 }
2152
2153 *q = EchoReq;
2154 *(u8 *)(q + 1) = (time_now % 255); // ID
2155 *(u16 *)(q + 2) = htons(8); // Length
2156 *(u32 *)(q + 4) = 0; // Magic Number (not supported)
2157
2158 log(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2159 (int)(time_now - session[s].last_packet));
2160 tunnelsend(b, 24, session[s].tunnel); // send it
2161 if (++count >= MAX_ACTIONS) break;
2162 continue;
2163 }
2164 }
2165 if (config->accounting_dir && next_acct <= TIME)
2166 {
2167 // Dump accounting data
2168 next_acct = TIME + ACCT_TIME;
2169 dump_acct_info();
2170 }
2171
2172 if (count >= MAX_ACTIONS)
2173 return 1; // Didn't finish!
2174
2175 log(3, 0, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2176 return 0;
2177 }
2178
2179
2180 //
2181 // Are we in the middle of a tunnel update, or radius
2182 // requests??
2183 //
2184 int still_busy(void)
2185 {
2186 int i;
2187 static int last_talked = 0;
2188 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i) {
2189 if (!tunnel[i].controlc)
2190 continue;
2191
2192 if (last_talked != TIME) {
2193 log(2,0,0,0, "Tunnel %d still has un-acked control messages.\n", i);
2194 last_talked = TIME;
2195 }
2196 return 1;
2197 }
2198
2199 for (i = 1; i < MAXRADIUS; i++)
2200 {
2201 if (radius[i].state == RADIUSNULL)
2202 continue;
2203 if (radius[i].state == RADIUSWAIT)
2204 continue;
2205
2206 if (last_talked != TIME) {
2207 log(2,0,0,0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2208 last_talked = TIME;
2209 }
2210 return 1;
2211 }
2212
2213 return 0;
2214 }
2215
2216 // main loop - gets packets on tap or udp and processes them
2217 void mainloop(void)
2218 {
2219 fd_set cr;
2220 int cn, i;
2221 u8 buf[65536];
2222 struct timeval to;
2223 time_t next_cluster_ping = 0; // default 1 second pings.
2224 clockt next_clean = time_now + config->cleanup_interval;
2225
2226 log(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tapfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2227 udpfd, tapfd, cluster_sockfd, controlfd);
2228
2229 FD_ZERO(&cr);
2230 FD_SET(udpfd, &cr);
2231 FD_SET(tapfd, &cr);
2232 FD_SET(controlfd, &cr);
2233 FD_SET(clifd, &cr);
2234 if (cluster_sockfd) FD_SET(cluster_sockfd, &cr);
2235 cn = udpfd;
2236 if (cn < tapfd) cn = tapfd;
2237 if (cn < controlfd) cn = controlfd;
2238 if (cn < clifd) cn = clifd;
2239 if (cn < cluster_sockfd) cn = cluster_sockfd;
2240 for (i = 0; i < config->num_radfds; i++)
2241 {
2242 if (!radfds[i]) continue;
2243 FD_SET(radfds[i], &cr);
2244 if (radfds[i] > cn)
2245 cn = radfds[i];
2246 }
2247
2248 while (!main_quit || still_busy())
2249 {
2250 fd_set r;
2251 int n = cn;
2252 #ifdef BGP
2253 fd_set w;
2254 int bgp_set[BGP_NUM_PEERS];
2255 #endif /* BGP */
2256
2257 if (config->reload_config)
2258 {
2259 // Update the config state based on config settings
2260 update_config();
2261 }
2262
2263 memcpy(&r, &cr, sizeof(fd_set));
2264 to.tv_sec = 0;
2265 to.tv_usec = 100000; // 1/10th of a second.
2266
2267 #ifdef BGP
2268 FD_ZERO(&w);
2269 for (i = 0; i < BGP_NUM_PEERS; i++)
2270 {
2271 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2272 if (bgp_set[i] & 1)
2273 {
2274 FD_SET(bgp_peers[i].sock, &r);
2275 if (bgp_peers[i].sock > n)
2276 n = bgp_peers[i].sock;
2277 }
2278
2279 if (bgp_set[i] & 2)
2280 {
2281 FD_SET(bgp_peers[i].sock, &w);
2282 if (bgp_peers[i].sock > n)
2283 n = bgp_peers[i].sock;
2284 }
2285 }
2286
2287 n = select(n + 1, &r, &w, 0, &to);
2288 #else /* BGP */
2289 n = select(n + 1, &r, 0, 0, &to);
2290 #endif /* BGP */
2291
2292 TIME = now();
2293 if (n < 0)
2294 {
2295 if (errno == EINTR)
2296 continue;
2297
2298 log(0, 0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2299 main_quit++;
2300 break;
2301 }
2302 else if (n)
2303 {
2304 struct sockaddr_in addr;
2305 int alen = sizeof(addr);
2306 if (FD_ISSET(udpfd, &r))
2307 {
2308 int c, n;
2309 for (c = 0; c < config->multi_read_count; c++)
2310 {
2311 if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2312 processudp(buf, n, &addr);
2313 else
2314 break;
2315 }
2316 }
2317 if (FD_ISSET(tapfd, &r))
2318 {
2319 int c, n;
2320 for (c = 0; c < config->multi_read_count; c++)
2321 {
2322 if ((n = read(tapfd, buf, sizeof(buf))) > 0)
2323 processtap(buf, n);
2324 else
2325 break;
2326 }
2327 }
2328 for (i = 0; i < config->num_radfds; i++)
2329 if (FD_ISSET(radfds[i], &r))
2330 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2331 if (FD_ISSET(cluster_sockfd, &r)) {
2332 int size;
2333 size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
2334 processcluster(buf, size, addr.sin_addr.s_addr);
2335 }
2336 if (FD_ISSET(controlfd, &r))
2337 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr);
2338 if (FD_ISSET(clifd, &r))
2339 {
2340 struct sockaddr_in addr;
2341 int sockfd;
2342 int len = sizeof(addr);
2343
2344 if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
2345 {
2346 log(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
2347 continue;
2348 }
2349 else
2350 {
2351 cli_do(sockfd);
2352 close(sockfd);
2353 }
2354 }
2355 }
2356
2357 // Runs on every machine (master and slaves).
2358 if (cluster_sockfd && next_cluster_ping <= time_now)
2359 {
2360 // Check to see which of the cluster is still alive..
2361 next_cluster_ping = time_now + 1;
2362 cluster_send_ping(basetime);
2363
2364 cluster_check_master();
2365
2366 cluster_heartbeat(config->cluster_highest_sessionid, sessionfree, config->cluster_highest_tunnelid); // Only does anything if we're a master.
2367 master_update_counts(); // If we're a slave, send our byte counters to our master.
2368 }
2369
2370 // Run token bucket filtering queue..
2371 // Only run it every 1/10th of a second.
2372 // Runs on all machines both master and slave.
2373 {
2374 static clockt last_run = 0;
2375 if (last_run != TIME) {
2376 last_run = TIME;
2377 tbf_run_timer();
2378 }
2379 }
2380
2381 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2382 * something to read, else under load this will never actually run....
2383 *
2384 */
2385 if (config->cluster_iam_master && next_clean <= time_now) {
2386 if (regular_cleanups()) { // Did it finish?
2387 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2388 } else {
2389 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2390 }
2391 }
2392
2393 #ifdef BGP
2394 for (i = 0; i < BGP_NUM_PEERS; i++)
2395 {
2396 bgp_process(&bgp_peers[i],
2397 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
2398 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
2399 }
2400 #endif /* BGP */
2401 }
2402
2403 // Are we the master and shutting down??
2404 if (config->cluster_iam_master) {
2405
2406 cluster_heartbeat(config->cluster_highest_sessionid, sessionfree,
2407 config->cluster_highest_tunnelid); // Flush any queued changes..
2408 }
2409
2410 // Ok. Notify everyone we're shutting down. If we're
2411 // the master, this will force an election.
2412 cluster_send_ping(0);
2413
2414 //
2415 // Important!!! We MUST not process any packets past this point!
2416 }
2417
2418 // Init data structures
2419 void initdata(void)
2420 {
2421 int i;
2422
2423 _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2424 if (_statistics == MAP_FAILED)
2425 {
2426 log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
2427 exit(1);
2428 }
2429 config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2430 if (config == MAP_FAILED)
2431 {
2432 log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
2433 exit(1);
2434 }
2435 memset(config, 0, sizeof(struct configt));
2436 time(&config->start_time);
2437 strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
2438 tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2439 if (tunnel == MAP_FAILED)
2440 {
2441 log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
2442 exit(1);
2443 }
2444 session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2445 if (session == MAP_FAILED)
2446 {
2447 log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
2448 exit(1);
2449 }
2450
2451 sess_count = mmap(NULL, sizeof(sessioncountt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2452 if (sess_count == MAP_FAILED)
2453 {
2454 log(0, 0, 0, 0, "Error doing mmap for sessions_count: %s\n", strerror(errno));
2455 exit(1);
2456 }
2457
2458 radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2459 if (radius == MAP_FAILED)
2460 {
2461 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2462 exit(1);
2463 }
2464 ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2465 if (ip_address_pool == MAP_FAILED)
2466 {
2467 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2468 exit(1);
2469 }
2470 #ifdef RINGBUFFER
2471 ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2472 if (ringbuffer == MAP_FAILED)
2473 {
2474 log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
2475 exit(1);
2476 }
2477 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2478 #endif
2479
2480 cli_session_kill = mmap(NULL, sizeof(sessionidt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2481 if (cli_session_kill == MAP_FAILED)
2482 {
2483 log(0, 0, 0, 0, "Error doing mmap for cli session kill: %s\n", strerror(errno));
2484 exit(1);
2485 }
2486 memset(cli_session_kill, 0, sizeof(sessionidt) * MAXSESSION);
2487 cli_tunnel_kill = mmap(NULL, sizeof(tunnelidt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2488 if (cli_tunnel_kill == MAP_FAILED)
2489 {
2490 log(0, 0, 0, 0, "Error doing mmap for cli tunnel kill: %s\n", strerror(errno));
2491 exit(1);
2492 }
2493 memset(cli_tunnel_kill, 0, sizeof(tunnelidt) * MAXSESSION);
2494
2495 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2496 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2497 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2498 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2499
2500 // Put all the sessions on the free list marked as undefined.
2501 for (i = 1; i < MAXSESSION - 1; i++) {
2502 session[i].next = i + 1;
2503 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2504 }
2505 session[MAXSESSION - 1].next = 0;
2506 sessionfree = 1;
2507
2508 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2509 for (i = 1; i < MAXTUNNEL- 1; i++) {
2510 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2511 }
2512
2513 if (!*hostname)
2514 {
2515 // Grab my hostname unless it's been specified
2516 gethostname(hostname, sizeof(hostname));
2517 }
2518 _statistics->start_time = _statistics->last_reset = time(NULL);
2519
2520 #ifdef BGP
2521 bgp_peers = mmap(NULL, sizeof(struct bgp_peer) * BGP_NUM_PEERS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
2522 if (bgp_peers == MAP_FAILED)
2523 {
2524 log(0, 0, 0, 0, "Error doing mmap for bgp: %s\n", strerror(errno));
2525 exit(1);
2526 }
2527 #endif /* BGP */
2528 }
2529
2530 void initiptables(void)
2531 {
2532 /* Flush the tables here so that we have a clean slate */
2533
2534 // Not needed. 'nat' is setup by garden.c
2535 // mangle isn't used (as throttling is done by tbf inhouse).
2536 }
2537
2538 int assign_ip_address(sessionidt s)
2539 {
2540 u32 i;
2541 int best = -1;
2542 clockt best_time = time_now;
2543 char *u = session[s].user;
2544 char reuse = 0;
2545
2546
2547 CSTAT(call_assign_ip_address);
2548
2549 for (i = 1; i < ip_pool_size; i++)
2550 {
2551 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2552 continue;
2553
2554 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2555 {
2556 best = i;
2557 reuse = 1;
2558 break;
2559 }
2560
2561 if (ip_address_pool[i].last < best_time)
2562 {
2563 best = i;
2564 if (!(best_time = ip_address_pool[i].last))
2565 break; // never used, grab this one
2566 }
2567 }
2568
2569 if (best < 0)
2570 {
2571 log(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2572 return 0;
2573 }
2574
2575 session[s].ip = ip_address_pool[best].address;
2576 session[s].ip_pool_index = best;
2577 ip_address_pool[best].assigned = 1;
2578 ip_address_pool[best].last = time_now;
2579 ip_address_pool[best].session = s;
2580 if (session[s].walled_garden)
2581 /* Don't track addresses of users in walled garden (note: this
2582 means that their address isn't "sticky" even if they get
2583 un-gardened). */
2584 ip_address_pool[best].user[0] = 0;
2585 else
2586 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2587
2588 STAT(ip_allocated);
2589 log(4, ip_address_pool[best].address, s, session[s].tunnel,
2590 "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
2591
2592 return 1;
2593 }
2594
2595 void free_ip_address(sessionidt s)
2596 {
2597 int i = session[s].ip_pool_index;
2598
2599 if (!session[s].ip)
2600 return; // what the?
2601
2602 if (i < 0) // Is this actually part of the ip pool?
2603 i = 0;
2604
2605 STAT(ip_freed);
2606 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2607 session[s].ip = 0;
2608 ip_address_pool[i].assigned = 0;
2609 ip_address_pool[i].session = 0;
2610 ip_address_pool[i].last = time_now;
2611
2612
2613 CSTAT(call_free_ip_address);
2614
2615 }
2616
2617 //
2618 // Fsck the address pool against the session table.
2619 // Normally only called when we become a master.
2620 //
2621 // This isn't perfect: We aren't keep tracking of which
2622 // users used to have an IP address.
2623 //
2624 void rebuild_address_pool(void)
2625 {
2626 int i;
2627
2628 //
2629 // Zero the IP pool allocation, and build
2630 // a map from IP address to pool index.
2631 for (i = 1; i < MAXIPPOOL; ++i) {
2632 ip_address_pool[i].assigned = 0;
2633 ip_address_pool[i].session = 0;
2634 if (!ip_address_pool[i].address)
2635 continue;
2636
2637 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2638 }
2639
2640 for (i = 0; i < MAXSESSION; ++i) {
2641 int ipid;
2642 if (!session[i].ip || !session[i].tunnel)
2643 continue;
2644 ipid = - lookup_ipmap(htonl(session[i].ip));
2645
2646 if (session[i].ip_pool_index < 0) { // Not allocated out of the pool.
2647 if (ipid < 1) // Not found in the pool either? good.
2648 continue;
2649
2650 log(0, 0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2651 i, inet_toa(session[i].ip), ipid);
2652
2653 // Fall through and process it as part of the pool.
2654 }
2655
2656
2657 if (ipid > MAXIPPOOL || ipid < 0) {
2658 log(0, 0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2659 ipid = -1;
2660 session[i].ip_pool_index = ipid;
2661 continue;
2662 }
2663
2664 ip_address_pool[ipid].assigned = 1;
2665 ip_address_pool[ipid].session = i;
2666 ip_address_pool[ipid].last = time_now;
2667 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2668 session[i].ip_pool_index = ipid;
2669 cache_ipmap(session[i].ip, i); // Fix the ip map.
2670 }
2671 }
2672
2673 //
2674 // Fix the address pool to match a changed session.
2675 // (usually when the master sends us an update).
2676 void fix_address_pool(int sid)
2677 {
2678 int ipid;
2679
2680 ipid = session[sid].ip_pool_index;
2681
2682 if (ipid > ip_pool_size)
2683 return; // Ignore it. rebuild_address_pool will fix it up.
2684
2685 if (ip_address_pool[ipid].address != session[sid].ip)
2686 return; // Just ignore it. rebuild_address_pool will take care of it.
2687
2688 ip_address_pool[ipid].assigned = 1;
2689 ip_address_pool[ipid].session = sid;
2690 ip_address_pool[ipid].last = time_now;
2691 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2692 }
2693
2694 //
2695 // Add a block of addresses to the IP pool to hand out.
2696 //
2697 void add_to_ip_pool(u32 addr, u32 mask)
2698 {
2699 int i;
2700 if (mask == 0)
2701 mask = 0xffffffff; // Host route only.
2702
2703 addr &= mask;
2704
2705 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2706 return ;
2707
2708 for (i = addr ;(i & mask) == addr; ++i)
2709 {
2710 if ((i & 0xff) == 0 || (i&0xff) == 255)
2711 continue; // Skip 0 and broadcast addresses.
2712
2713 ip_address_pool[ip_pool_size].address = i;
2714 ip_address_pool[ip_pool_size].assigned = 0;
2715 ++ip_pool_size;
2716 if (ip_pool_size >= MAXIPPOOL)
2717 {
2718 log(0,0,0,0, "Overflowed IP pool adding %s\n", inet_toa(htonl(addr)) );
2719 return;
2720 }
2721 }
2722 }
2723
2724 // Initialize the IP address pool
2725 void initippool()
2726 {
2727 FILE *f;
2728 char *p;
2729 char buf[4096];
2730 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2731
2732 if (!(f = fopen(IPPOOLFILE, "r")))
2733 {
2734 log(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2735 exit(1);
2736 }
2737
2738 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2739 {
2740 char *pool = buf;
2741 buf[4095] = 0; // Force it to be zero terminated/
2742
2743 if (*buf == '#' || *buf == '\n')
2744 continue; // Skip comments / blank lines
2745 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2746 if ((p = (char *)strchr(buf, ':')))
2747 {
2748 ipt src;
2749 *p = '\0';
2750 src = inet_addr(buf);
2751 if (src == INADDR_NONE)
2752 {
2753 log(0, 0, 0, 0, "Invalid address pool IP %s\n", buf);
2754 exit(1);
2755 }
2756 // This entry is for a specific IP only
2757 if (src != config->bind_address)
2758 continue;
2759 *p = ':';
2760 pool = p+1;
2761 }
2762 if ((p = (char *)strchr(pool, '/')))
2763 {
2764 // It's a range
2765 int numbits = 0;
2766 u32 start = 0, mask = 0;
2767
2768 log(2, 0, 0, 0, "Adding IP address range %s\n", buf);
2769 *p++ = 0;
2770 if (!*p || !(numbits = atoi(p)))
2771 {
2772 log(0, 0, 0, 0, "Invalid pool range %s\n", buf);
2773 continue;
2774 }
2775 start = ntohl(inet_addr(pool));
2776 mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
2777
2778 // Add a static route for this pool
2779 log(5, 0, 0, 0, "Adding route for address pool %s/%u\n", inet_toa(htonl(start)), 32 + mask);
2780 routeset(0, start, mask, 0, 1);
2781
2782 add_to_ip_pool(start, mask);
2783 }
2784 else
2785 {
2786 // It's a single ip address
2787 add_to_ip_pool(inet_addr(pool), 0);
2788 }
2789 }
2790 fclose(f);
2791 log(1, 0, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2792 }
2793
2794 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
2795 {
2796 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2797 return;
2798
2799 snoop_addr.sin_addr.s_addr = destination;
2800 snoop_addr.sin_port = ntohs(port);
2801
2802 log(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
2803 packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
2804 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
2805 log(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
2806 STAT(packets_snooped);
2807 }
2808
2809 void dump_acct_info()
2810 {
2811 char filename[1024];
2812 char timestr[64];
2813 time_t t = time(NULL);
2814 int i;
2815 FILE *f = NULL;
2816
2817
2818 CSTAT(call_dump_acct_info);
2819
2820 strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
2821 snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
2822
2823 for (i = 0; i < MAXSESSION; i++)
2824 {
2825 if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
2826 continue;
2827 if (!f)
2828 {
2829 time_t now = time(NULL);
2830 if (!(f = fopen(filename, "w")))
2831 {
2832 log(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
2833 return;
2834 }
2835 log(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
2836 fprintf(f, "# dslwatch.pl dump file V1.01\n"
2837 "# host: %s\n"
2838 "# time: %ld\n"
2839 "# uptime: %ld\n"
2840 "# format: username ip qos uptxoctets downrxoctets\n",
2841 hostname,
2842 now,
2843 now - basetime);
2844 }
2845
2846 log(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
2847 fprintf(f, "%s %s %d %u %u\n",
2848 session[i].user, // username
2849 inet_toa(htonl(session[i].ip)), // ip
2850 (session[i].throttle) ? 2 : 1, // qos
2851 (u32)session[i].cin, // uptxoctets
2852 (u32)session[i].cout); // downrxoctets
2853
2854 session[i].pin = session[i].cin = 0;
2855 session[i].pout = session[i].cout = 0;
2856 }
2857
2858 if (f) fclose(f);
2859 }
2860
2861 // Main program
2862 int main(int argc, char *argv[])
2863 {
2864 int o;
2865
2866 _program_name = strdup(argv[0]);
2867
2868 time(&basetime); // start clock
2869
2870 // scan args
2871 while ((o = getopt(argc, argv, "vc:h:a:")) >= 0)
2872 {
2873 switch (o)
2874 {
2875 case 'd':
2876 // Double fork to detach from terminal
2877 if (fork()) exit(0);
2878 if (fork()) exit(0);
2879 break;
2880 case 'v':
2881 config->debug++;
2882 break;
2883 case 'h':
2884 strncpy(hostname, optarg, 999);
2885 break;
2886 case '?':
2887 default:
2888 printf("Args are:\n"
2889 "\t-d\tDetach from terminal\n"
2890 "\t-c <file>\tConfig file\n"
2891 "\t-h <hostname>\tForce hostname\n"
2892 "\t-a <address>\tUse specific address\n"
2893 "\t-v\t\tDebug\n");
2894
2895 return (0);
2896 break;
2897 }
2898 }
2899
2900 // Start the timer routine off
2901 time(&time_now);
2902 strftime(time_now_string, 64, "%Y-%m-%d %H:%M:%S", localtime(&time_now));
2903 signal(SIGALRM, sigalrm_handler);
2904 siginterrupt(SIGALRM, 0);
2905
2906 initiptables();
2907 initplugins();
2908 initdata();
2909 init_tbf();
2910 init_cli();
2911 read_config_file();
2912
2913 log(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
2914 log(0, 0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
2915 log(0, 0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
2916 {
2917 struct rlimit rlim;
2918 rlim.rlim_cur = RLIM_INFINITY;
2919 rlim.rlim_max = RLIM_INFINITY;
2920 // Remove the maximum core size
2921 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
2922 log(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
2923 // Make core dumps go to /tmp
2924 chdir("/tmp");
2925 }
2926
2927 if (config->scheduler_fifo)
2928 {
2929 int ret;
2930 struct sched_param params = {0};
2931 params.sched_priority = 1;
2932
2933 if (get_nprocs() < 2)
2934 {
2935 log(0, 0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
2936 config->scheduler_fifo = 0;
2937 }
2938 else
2939 {
2940 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
2941 {
2942 log(1, 0, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
2943 }
2944 else
2945 {
2946 log(0, 0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
2947 config->scheduler_fifo = 0;
2948 }
2949 }
2950 }
2951
2952 /* Set up the cluster communications port. */
2953 if (cluster_init(config->bind_address) < 0)
2954 exit(1);
2955
2956 #ifdef BGP
2957 signal(SIGPIPE, SIG_IGN);
2958 bgp_setup(config->as_number);
2959 bgp_add_route(config->bind_address, 0xffffffff);
2960 if (*config->bgp_peer[0])
2961 bgp_start(&bgp_peers[0], config->bgp_peer[0],
2962 config->bgp_peer_as[0], 0); /* 0 = routing disabled */
2963
2964 if (*config->bgp_peer[1])
2965 bgp_start(&bgp_peers[1], config->bgp_peer[1],
2966 config->bgp_peer_as[1], 0);
2967 #endif /* BGP */
2968
2969 inittap();
2970 log(1, 0, 0, 0, "Set up on interface %s\n", config->tapdevice);
2971
2972 initudp();
2973 initrad();
2974 initippool();
2975
2976 read_state();
2977
2978 signal(SIGHUP, sighup_handler);
2979 signal(SIGTERM, sigterm_handler);
2980 signal(SIGINT, sigterm_handler);
2981 signal(SIGQUIT, sigquit_handler);
2982 signal(SIGCHLD, sigchild_handler);
2983
2984 alarm(1);
2985
2986 // Drop privileges here
2987 if (config->target_uid > 0 && geteuid() == 0)
2988 setuid(config->target_uid);
2989
2990 mainloop();
2991
2992 #ifdef BGP
2993 /* try to shut BGP down cleanly; with luck the sockets will be
2994 writable since we're out of the select */
2995 {
2996 int i;
2997 for (i = 0; i < BGP_NUM_PEERS; i++)
2998 if (bgp_peers[i].state == Established)
2999 bgp_stop(&bgp_peers[i]);
3000 }
3001 #endif /* BGP */
3002
3003 /* remove plugins (so cleanup code gets run) */
3004 plugins_done();
3005
3006 /* kill CLI children */
3007 signal(SIGTERM, SIG_IGN);
3008 kill(0, SIGTERM);
3009 return 0;
3010 }
3011
3012 void sighup_handler(int junk)
3013 {
3014 if (log_stream && log_stream != stderr)
3015 {
3016 fclose(log_stream);
3017 log_stream = NULL;
3018 }
3019
3020 read_config_file();
3021 }
3022
3023 void sigalrm_handler(int junk)
3024 {
3025 // Log current traffic stats
3026
3027 snprintf(config->bandwidth, sizeof(config->bandwidth),
3028 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3029 (udp_rx / 1024.0 / 1024.0 * 8),
3030 (eth_tx / 1024.0 / 1024.0 * 8),
3031 (eth_rx / 1024.0 / 1024.0 * 8),
3032 (udp_tx / 1024.0 / 1024.0 * 8),
3033 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3034 udp_rx_pkt, eth_rx_pkt);
3035
3036 udp_tx = udp_rx = 0;
3037 udp_rx_pkt = eth_rx_pkt = 0;
3038 eth_tx = eth_rx = 0;
3039
3040 if (config->dump_speed)
3041 printf("%s\n", config->bandwidth);
3042
3043 // Update the internal time counter
3044 time(&time_now);
3045 strftime(time_now_string, 64, "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3046 alarm(1);
3047
3048 {
3049 // Run timer hooks
3050 struct param_timer p = { time_now };
3051 run_plugins(PLUGIN_TIMER, &p);
3052 }
3053
3054 }
3055
3056 void sigterm_handler(int junk)
3057 {
3058 log(1, 0, 0, 0, "Shutting down cleanly\n");
3059 if (config->save_state)
3060 dump_state();
3061
3062 main_quit++;
3063 }
3064
3065 void sigquit_handler(int junk)
3066 {
3067 int i;
3068
3069 log(1, 0, 0, 0, "Shutting down without saving sessions\n");
3070 for (i = 1; i < MAXSESSION; i++)
3071 {
3072 if (session[i].opened)
3073 sessionkill(i, "L2TPNS Closing");
3074 }
3075 for (i = 1; i < MAXTUNNEL; i++)
3076 {
3077 if (tunnel[i].ip || tunnel[i].state)
3078 tunnelshutdown(i, "L2TPNS Closing");
3079 }
3080
3081 main_quit++;
3082 }
3083
3084 void sigchild_handler(int signal)
3085 {
3086 while (waitpid(-1, NULL, WNOHANG) > 0)
3087 ;
3088 }
3089
3090 void read_state()
3091 {
3092 struct stat sb;
3093 int i;
3094 ippoolt itmp;
3095 FILE *f;
3096 char magic[sizeof(DUMP_MAGIC)-1];
3097 u32 buf[2];
3098
3099 if (!config->save_state)
3100 {
3101 unlink(STATEFILE);
3102 return;
3103 }
3104
3105 if (stat(STATEFILE, &sb) < 0)
3106 {
3107 unlink(STATEFILE);
3108 return;
3109 }
3110
3111 if (sb.st_mtime < (time(NULL) - 60))
3112 {
3113 log(0, 0, 0, 0, "State file is too old to read, ignoring\n");
3114 unlink(STATEFILE);
3115 return;
3116 }
3117
3118 f = fopen(STATEFILE, "r");
3119 unlink(STATEFILE);
3120
3121 if (!f)
3122 {
3123 log(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3124 exit(1);
3125 }
3126
3127 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3128 {
3129 log(0, 0, 0, 0, "Bad state file magic\n");
3130 exit(1);
3131 }
3132
3133 log(1, 0, 0, 0, "Reading state information\n");
3134 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3135 {
3136 log(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3137 exit(1);
3138 }
3139
3140 if (buf[0] > ip_pool_size)
3141 {
3142 log(0, 0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3143 exit(1);
3144 }
3145
3146 log(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
3147 for (i = 0; i < buf[0]; i++)
3148 {
3149 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3150 {
3151 log(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3152 exit(1);
3153 }
3154
3155 if (itmp.address != ip_address_pool[i].address)
3156 {
3157 log(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3158 exit(1);
3159 }
3160
3161 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3162 }
3163
3164 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3165 {
3166 log(0, 0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3167 exit(1);
3168 }
3169
3170 log(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3171 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3172 {
3173 log(0, 0, 0, 0, "Error reading tunnel data from state file\n");
3174 exit(1);
3175 }
3176
3177 for (i = 0; i < MAXTUNNEL; i++)
3178 {
3179 tunnel[i].controlc = 0;
3180 tunnel[i].controls = NULL;
3181 tunnel[i].controle = NULL;
3182 if (*tunnel[i].hostname)
3183 log(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3184 }
3185
3186 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3187 {
3188 log(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
3189 exit(1);
3190 }
3191
3192 log(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
3193 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3194 {
3195 log(0, 0, 0, 0, "Error reading session data from state file\n");
3196 exit(1);
3197 }
3198
3199 for (i = 0; i < MAXSESSION; i++)
3200 {
3201 session[i].tbf_in = 0;
3202 session[i].tbf_out = 0;
3203 if (session[i].opened)
3204 {
3205 log(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
3206 if (session[i].ip)
3207 sessionsetup(session[i].tunnel, i);
3208 }
3209 }
3210
3211 fclose(f);
3212 log(0, 0, 0, 0, "Loaded saved state information\n");
3213 }
3214
3215 void dump_state()
3216 {
3217 FILE *f;
3218 u32 buf[2];
3219
3220 if (!config->save_state)
3221 return;
3222
3223 do {
3224 if (!(f = fopen(STATEFILE, "w")))
3225 break;
3226
3227 log(1, 0, 0, 0, "Dumping state information\n");
3228
3229 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC)-1, 1, f) != 1) break;
3230
3231 log(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3232 buf[0] = ip_pool_size;
3233 buf[1] = sizeof(ippoolt);
3234 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3235 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size) break;
3236
3237 log(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3238 buf[0] = MAXTUNNEL;
3239 buf[1] = sizeof(tunnelt);
3240 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3241 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL) break;
3242
3243 log(2, 0, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3244 buf[0] = MAXSESSION;
3245 buf[1] = sizeof(sessiont);
3246 if (fwrite(buf, sizeof(buf), 1, f) != 1) break;
3247 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION) break;
3248
3249 if (fclose(f) == 0) return; // OK
3250 } while (0);
3251
3252 log(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3253 unlink(STATEFILE);
3254 }
3255
3256 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
3257 {
3258 MD5_CTX ctx;
3259 *challenge_response = NULL;
3260
3261 if (!*config->l2tpsecret)
3262 {
3263 log(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3264 return;
3265 }
3266
3267 log(4, 0, 0, 0, " Building challenge response for CHAP request\n");
3268
3269 *challenge_response = (char *)calloc(17, 1);
3270
3271 MD5Init(&ctx);
3272 MD5Update(&ctx, &id, 1);
3273 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3274 MD5Update(&ctx, challenge, challenge_length);
3275 MD5Final(*challenge_response, &ctx);
3276
3277 return;
3278 }
3279
3280 static int facility_value(char *name)
3281 {
3282 int i;
3283 for (i = 0; facilitynames[i].c_name; i++)
3284 {
3285 if (strcmp(facilitynames[i].c_name, name) == 0)
3286 return facilitynames[i].c_val;
3287 }
3288 return 0;
3289 }
3290
3291 void update_config()
3292 {
3293 int i;
3294
3295 // Update logging
3296 closelog();
3297 syslog_log = 0;
3298 if (log_stream)
3299 {
3300 fclose(log_stream);
3301 log_stream = NULL;
3302 }
3303 if (*config->log_filename)
3304 {
3305 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3306 {
3307 char *p = config->log_filename + 7;
3308 if (*p)
3309 {
3310 openlog("l2tpns", LOG_PID, facility_value(p));
3311 syslog_log = 1;
3312 }
3313 }
3314 else if (strchr(config->log_filename, '/') == config->log_filename)
3315 {
3316 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3317 {
3318 fseek(log_stream, 0, SEEK_END);
3319 setbuf(log_stream, NULL);
3320 }
3321 else
3322 {
3323 log_stream = stderr;
3324 setbuf(log_stream, NULL);
3325 }
3326 }
3327 }
3328 else
3329 {
3330 log_stream = stderr;
3331 setbuf(log_stream, NULL);
3332 }
3333
3334
3335 // Update radius
3336 config->numradiusservers = 0;
3337 for (i = 0; i < MAXRADSERVER; i++)
3338 if (config->radiusserver[i]) config->numradiusservers++;
3339
3340 if (!config->numradiusservers)
3341 {
3342 log(0, 0, 0, 0, "No RADIUS servers defined!\n");
3343 }
3344
3345 config->num_radfds = 2 << RADIUS_SHIFT;
3346
3347 // Update plugins
3348 for (i = 0; i < MAXPLUGINS; i++)
3349 {
3350 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3351 continue;
3352 if (*config->plugins[i])
3353 {
3354 // Plugin added
3355 add_plugin(config->plugins[i]);
3356 }
3357 else if (*config->old_plugins[i])
3358 {
3359 // Plugin removed
3360 remove_plugin(config->old_plugins[i]);
3361 }
3362 }
3363 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3364 if (!config->cleanup_interval) config->cleanup_interval = 10;
3365 if (!config->multi_read_count) config->multi_read_count = 10;
3366 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3367 if (!*config->cluster_interface)
3368 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3369
3370 if (!config->cluster_hb_interval)
3371 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3372
3373 if (!config->cluster_hb_timeout)
3374 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3375
3376 config->reload_config = 0;
3377 }
3378
3379 void read_config_file()
3380 {
3381 FILE *f;
3382
3383 if (!config->config_file) return;
3384 if (!(f = fopen(config->config_file, "r"))) {
3385 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3386 return;
3387 }
3388
3389 log(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
3390 cli_do_file(f);
3391 log(3, 0, 0, 0, "Done reading config file\n");
3392 fclose(f);
3393 update_config();
3394 }
3395
3396 int sessionsetup(tunnelidt t, sessionidt s)
3397 {
3398 // A session now exists, set it up
3399 ipt ip;
3400 char *user;
3401 sessionidt i;
3402 int r;
3403
3404 CSTAT(call_sessionsetup);
3405
3406
3407 log(3, session[s].ip, s, t, "Doing session setup for session\n");
3408
3409 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3410 {
3411 assign_ip_address(s);
3412 if (session[s].ip)
3413 log(3, 0, s, t, " No IP allocated. Assigned %s from pool\n",
3414 inet_toa(htonl(session[s].ip)));
3415 else
3416 log(0, 0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3417 }
3418
3419
3420 // Make sure this is right
3421 session[s].tunnel = t;
3422
3423 // zap old sessions with same IP and/or username
3424 // Don't kill gardened sessions - doing so leads to a DoS
3425 // from someone who doesn't need to know the password
3426 {
3427 ip = session[s].ip;
3428 user = session[s].user;
3429 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3430 {
3431 if (i == s) continue;
3432 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3433 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3434 sessionkill(i, "Duplicate session for users");
3435 }
3436 }
3437
3438 // Add the route for this session.
3439 //
3440 // Static IPs need to be routed. Anything else
3441 // is part of the IP address pool and is already routed,
3442 // it just needs to be added to the IP cache.
3443 if (session[s].ip_pool_index == -1) // static ip
3444 routeset(s, session[s].ip, 0, 0, 1);
3445 else
3446 cache_ipmap(session[s].ip, s);
3447
3448 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3449 routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1);
3450
3451 if (!session[s].sid) { // did this session just finish radius?
3452 log(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
3453 sendipcp(t, s);
3454 session[s].sid = ++last_sid;
3455 }
3456
3457 // Run the plugin's against this new session.
3458 {
3459 struct param_new_session data = { &tunnel[t], &session[s] };
3460 run_plugins(PLUGIN_NEW_SESSION, &data);
3461 }
3462
3463 // Force throttling on or off (Actually : refresh the current throttling status)
3464 // This has the advantage of cleaning up after another throttled user who may have left
3465 // firewall rules lying around
3466 throttle_session(s, session[s].throttle);
3467
3468 session[s].last_packet = time_now;
3469
3470 {
3471 char *sessionip, *tunnelip;
3472 sessionip = strdup(inet_toa(htonl(session[s].ip)));
3473 tunnelip = strdup(inet_toa(htonl(tunnel[t].ip)));
3474 log(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
3475 session[s].user, sessionip, tunnelip, tunnel[t].hostname);
3476 if (sessionip) free(sessionip);
3477 if (tunnelip) free(tunnelip);
3478 }
3479
3480 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3481
3482 return 1; // RADIUS OK and IP allocated, done...
3483 }
3484
3485 //
3486 // This session just got dropped on us by the master or something.
3487 // Make sure our tables up up to date...
3488 //
3489 int load_session(sessionidt s, sessiont *new)
3490 {
3491 int i;
3492
3493 // Sanity checks.
3494 if (new->ip_pool_index >= MAXIPPOOL ||
3495 new->tunnel >= MAXTUNNEL) {
3496 log(0,0,s,0, "Strange session update received!\n");
3497 // FIXME! What to do here?
3498 return 0;
3499 }
3500
3501 //
3502 // Ok. All sanity checks passed. Now we're committed to
3503 // loading the new session.
3504 //
3505
3506 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3507
3508
3509 if (new->ip != session[s].ip) // Changed ip. fix up hash tables.
3510 {
3511 if (session[s].ip) // If there's an old one, remove it.
3512 {
3513 // Remove any routes if the IP has changed
3514 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3515 {
3516 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3517 session[s].route[i].ip = 0;
3518 }
3519
3520 if (session[s].ip_pool_index == -1) // static IP
3521 routeset(s, session[s].ip, 0, 0, 0);
3522 else // It's part of the IP pool, remove it manually.
3523 uncache_ipmap(session[s].ip);
3524 }
3525
3526 if (new->ip) { // If there's a new one, add it.
3527 if (new->ip_pool_index == -1)
3528 routeset(s, new->ip, 0, 0, 1);
3529 else
3530 cache_ipmap(new->ip, s);
3531 }
3532 }
3533
3534 // Update routed networks
3535 for (i = 0; i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3536 {
3537 if (new->route[i].ip == session[s].route[i].ip &&
3538 new->route[i].mask == session[s].route[i].mask)
3539 continue;
3540
3541 if (session[s].route[i].ip) // Remove the old one if it exists.
3542 routeset(s, session[s].route[i].ip, session[s].route[i].mask, session[s].ip, 0);
3543
3544 if (new->route[i].ip) // Add the new one if it exists.
3545 routeset(s, new->route[i].ip, new->route[i].mask, new->ip, 1);
3546 }
3547
3548
3549
3550 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3551 // for walking the sessions to forward byte counts to the master.
3552 config->cluster_highest_sessionid = s;
3553
3554 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3555
3556 // Do fixups into address pool.
3557 if (new->ip_pool_index != -1)
3558 fix_address_pool(s);
3559 return 1;
3560 }
3561
3562 #ifdef RINGBUFFER
3563 void ringbuffer_dump(FILE *stream)
3564 {
3565 int i = ringbuffer->head;
3566
3567 while (i != ringbuffer->tail)
3568 {
3569 if (*ringbuffer->buffer[i].message)
3570 fprintf(stream, "%d-%s", ringbuffer->buffer[i].level, ringbuffer->buffer[i].message);
3571 if (++i == ringbuffer->tail) break;
3572 if (i == RINGBUFFER_SIZE) i = 0;
3573 }
3574 }
3575 #endif
3576
3577 void initplugins()
3578 {
3579 int i;
3580
3581 loaded_plugins = ll_init();
3582 // Initialize the plugins to nothing
3583 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3584 plugins[i] = ll_init();
3585 }
3586
3587 static void *open_plugin(char *plugin_name, int load)
3588 {
3589 char path[256] = "";
3590
3591 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3592 log(2, 0, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3593 return dlopen(path, RTLD_NOW);
3594 }
3595
3596 void add_plugin(char *plugin_name)
3597 {
3598 static struct pluginfuncs funcs = {
3599 _log,
3600 _log_hex,
3601 inet_toa,
3602 sessionbyuser,
3603 sessiontbysessionidt,
3604 sessionidtbysessiont,
3605 sessionkill,
3606 radiusnew,
3607 radiussend,
3608 };
3609
3610 void *p = open_plugin(plugin_name, 1);
3611 int (*initfunc)(struct pluginfuncs *);
3612 int i;
3613
3614 if (!p)
3615 {
3616 log(1, 0, 0, 0, " Plugin load failed: %s\n", dlerror());
3617 return;
3618 }
3619
3620 if (ll_contains(loaded_plugins, p))
3621 {
3622 dlclose(p);
3623 return;
3624 }
3625
3626 {
3627 int *v = dlsym(p, "__plugin_api_version");
3628 if (!v || *v != PLUGIN_API_VERSION)
3629 {
3630 log(1, 0, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
3631 dlclose(p);
3632 return;
3633 }
3634 }
3635
3636 if ((initfunc = dlsym(p, "plugin_init")))
3637 {
3638 if (!initfunc(&funcs))
3639 {
3640 log(1, 0, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
3641 dlclose(p);
3642 return;
3643 }
3644 }
3645
3646 ll_push(loaded_plugins, p);
3647
3648 for (i = 0; i < max_plugin_functions; i++)
3649 {
3650 void *x;
3651 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3652 {
3653 log(3, 0, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
3654 ll_push(plugins[i], x);
3655 }
3656 }
3657
3658 log(2, 0, 0, 0, " Loaded plugin %s\n", plugin_name);
3659 }
3660
3661 static void run_plugin_done(void *plugin)
3662 {
3663 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
3664
3665 if (donefunc)
3666 donefunc();
3667 }
3668
3669 void remove_plugin(char *plugin_name)
3670 {
3671 void *p = open_plugin(plugin_name, 0);
3672 int i;
3673
3674 if (!p)
3675 return;
3676
3677 for (i = 0; i < max_plugin_functions; i++)
3678 {
3679 void *x;
3680 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3681 ll_delete(plugins[i], x);
3682 }
3683
3684 if (ll_contains(loaded_plugins, p))
3685 {
3686 ll_delete(loaded_plugins, p);
3687 run_plugin_done(p);
3688 }
3689
3690 dlclose(p);
3691 log(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
3692 }
3693
3694 int run_plugins(int plugin_type, void *data)
3695 {
3696 int (*func)(void *data);
3697 if (!plugins[plugin_type] || plugin_type > max_plugin_functions) return 1;
3698
3699 ll_reset(plugins[plugin_type]);
3700 while ((func = ll_next(plugins[plugin_type])))
3701 {
3702 int rc;
3703 rc = func(data);
3704 if (rc == PLUGIN_RET_STOP) return 1;
3705 if (rc == PLUGIN_RET_ERROR) return 0;
3706 }
3707 return 1;
3708 }
3709
3710 void plugins_done()
3711 {
3712 void *p;
3713
3714 ll_reset(loaded_plugins);
3715 while ((p = ll_next(loaded_plugins)))
3716 run_plugin_done(p);
3717 }
3718
3719 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr)
3720 {
3721 char *resp;
3722 int l;
3723 struct param_control param = { buf, len, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), NULL, 0, 0 };
3724
3725
3726 if (log_stream && config->debug >= 4)
3727 {
3728 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
3729 dump_packet(buf, log_stream);
3730 }
3731
3732 resp = calloc(1400, 1);
3733 l = new_packet(PKT_RESP_ERROR, resp);
3734 *(int *)(resp + 6) = *(int *)(buf + 6);
3735
3736 param.type = ntohs(*(short *)(buf + 2));
3737 param.id = ntohl(*(int *)(buf + 6));
3738 param.data_length = ntohs(*(short *)(buf + 4)) - 10;
3739 param.data = (param.data_length > 0) ? (char *)(buf + 10) : NULL;
3740 param.response = resp;
3741 param.response_length = l;
3742
3743 run_plugins(PLUGIN_CONTROL, &param);
3744
3745 if (param.send_response)
3746 {
3747 send_packet(controlfd, ntohl(addr->sin_addr.s_addr), ntohs(addr->sin_port), param.response, param.response_length);
3748 log(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent Control packet response\n");
3749 }
3750
3751 free(resp);
3752 }
3753
3754 /*
3755 * HACK
3756 * Go through all of the tunnels and do some cleanups
3757 */
3758 void tunnel_clean()
3759 {
3760 int i;
3761
3762 log(1, 0, 0, 0, "Cleaning tunnels array\n");
3763
3764 for (i = 1; i < MAXTUNNEL; i++)
3765 {
3766 if (!tunnel[i].ip
3767 || !*tunnel[i].hostname
3768 || (tunnel[i].state == TUNNELDIE && tunnel[i].die >= time_now))
3769 {
3770 tunnelclear(i);
3771 }
3772 }
3773 }
3774
3775 void tunnelclear(tunnelidt t)
3776 {
3777 if (!t) return;
3778 memset(&tunnel[t], 0, sizeof(tunnel[t]));
3779 tunnel[t].state = TUNNELFREE;
3780 }
3781
3782 tunnelidt new_tunnel()
3783 {
3784 tunnelidt i;
3785 for (i = 1; i < MAXTUNNEL; i++)
3786 {
3787 if (tunnel[i].state == TUNNELFREE)
3788 {
3789 log(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
3790 if (i > config->cluster_highest_tunnelid)
3791 config->cluster_highest_tunnelid = i;
3792 return i;
3793 }
3794 }
3795 log(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
3796 return 0;
3797 }
3798
3799 //
3800 // We're becoming the master. Do any required setup..
3801 //
3802 // This is principally telling all the plugins that we're
3803 // now a master, and telling them about all the sessions
3804 // that are active too..
3805 //
3806 void become_master(void)
3807 {
3808 int s;
3809 run_plugins(PLUGIN_BECOME_MASTER, NULL);
3810
3811 for (s = 0; s < config->cluster_highest_sessionid ; ++s) {
3812 if (!session[s].tunnel) // Not an in-use session.
3813 continue;
3814
3815 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
3816 }
3817 }
3818
3819
3820
3821 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
3822 {
3823 int s, i;
3824 int count = 0;
3825 int buckets[64];
3826
3827 if (CLI_HELP_REQUESTED)
3828 return CLI_HELP_NO_ARGS;
3829
3830 time(&time_now);
3831 for (i = 0; i < 64;++i) buckets[i] = 0;
3832
3833 for (s = 0; s < config->cluster_highest_sessionid ; ++s) {
3834 int idle;
3835 if (!session[s].tunnel)
3836 continue;
3837
3838 idle = time_now - session[s].last_packet;
3839 idle /= 5 ; // In multiples of 5 seconds.
3840 if (idle < 0)
3841 idle = 0;
3842 if (idle > 63)
3843 idle = 63;
3844
3845 ++count;
3846 ++buckets[idle];
3847 }
3848
3849 for (i = 0; i < 63; ++i) {
3850 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
3851 }
3852 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
3853 cli_print(cli, "%d total sessions open.", count);
3854 return CLI_OK;
3855 }
3856
3857 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
3858 {
3859 int s, i;
3860 int count = 0;
3861 int buckets[64];
3862
3863 if (CLI_HELP_REQUESTED)
3864 return CLI_HELP_NO_ARGS;
3865
3866 time(&time_now);
3867 for (i = 0; i < 64;++i) buckets[i] = 0;
3868
3869 for (s = 0; s < config->cluster_highest_sessionid ; ++s) {
3870 int open = 0, d;
3871 if (!session[s].tunnel)
3872 continue;
3873
3874 d = time_now - session[s].opened;
3875 if (d < 0)
3876 d = 0;
3877 while (d > 1 && open < 32) {
3878 ++open;
3879 d >>= 1; // half.
3880 }
3881 ++count;
3882 ++buckets[open];
3883 }
3884
3885 s = 1;
3886 for (i = 0; i < 30; ++i) {
3887 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
3888 s <<= 1;
3889 }
3890 cli_print(cli, "%d total sessions open.", count);
3891 return CLI_OK;
3892 }