log regular cleanup actions at 3
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005 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 1.73.2.15 2005/05/31 12:09:33 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <stdarg.h>
23 #include <stdlib.h>
24 #include <stdio.h>
25 #include <string.h>
26 #include <ctype.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 #ifdef BGP
53 #include "bgp.h"
54 #endif /* BGP */
55
56 // Globals
57 configt *config = NULL; // all configuration
58 int tunfd = -1; // tun interface file handle. (network device)
59 int udpfd = -1; // UDP file handle
60 int controlfd = -1; // Control signal handle
61 int clifd = -1; // Socket listening for CLI connections.
62 int snoopfd = -1; // UDP file handle for sending out intercept data
63 int *radfds = NULL; // RADIUS requests file handles
64 int ifrfd = -1; // File descriptor for routing, etc
65 time_t basetime = 0; // base clock
66 char hostname[1000] = ""; // us.
67 static uint32_t sessionid = 0; // session id for radius accounting
68 static int syslog_log = 0; // are we logging to syslog
69 static FILE *log_stream = NULL; // file handle for direct logging (i.e. direct into file, not via syslog).
70 extern int cluster_sockfd; // Intra-cluster communications socket.
71 uint32_t last_id = 0; // Last used PPP SID. Can I kill this?? -- mo
72
73 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
74 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
75
76 static void *ip_hash[256]; // Mapping from IP address to session structures.
77
78 // Traffic counters.
79 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
80 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
81 uint32_t eth_tx = 0;
82
83 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
84 time_t time_now = 0; // Current time in seconds since epoch.
85 static char time_now_string[64] = {0}; // Current time as a string.
86 char main_quit = 0; // True if we're in the process of exiting.
87 linked_list *loaded_plugins;
88 linked_list *plugins[MAX_PLUGIN_TYPES];
89
90 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
91 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
92
93 config_descriptt config_values[] = {
94 CONFIG("debug", debug, INT),
95 CONFIG("log_file", log_filename, STRING),
96 CONFIG("pid_file", pid_file, STRING),
97 CONFIG("l2tp_secret", l2tpsecret, STRING),
98 CONFIG("primary_dns", default_dns1, IP),
99 CONFIG("secondary_dns", default_dns2, IP),
100 CONFIG("save_state", save_state, BOOL),
101 CONFIG("primary_radius", radiusserver[0], IP),
102 CONFIG("secondary_radius", radiusserver[1], IP),
103 CONFIG("primary_radius_port", radiusport[0], SHORT),
104 CONFIG("secondary_radius_port", radiusport[1], SHORT),
105 CONFIG("radius_accounting", radius_accounting, BOOL),
106 CONFIG("radius_secret", radiussecret, STRING),
107 CONFIG("bind_address", bind_address, IP),
108 CONFIG("peer_address", peer_address, IP),
109 CONFIG("send_garp", send_garp, BOOL),
110 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
111 CONFIG("throttle_buckets", num_tbfs, INT),
112 CONFIG("accounting_dir", accounting_dir, STRING),
113 CONFIG("setuid", target_uid, INT),
114 CONFIG("dump_speed", dump_speed, BOOL),
115 CONFIG("multi_read_count", multi_read_count, INT),
116 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
117 CONFIG("lock_pages", lock_pages, BOOL),
118 CONFIG("icmp_rate", icmp_rate, INT),
119 CONFIG("packet_limit", max_packets, INT),
120 CONFIG("cluster_address", cluster_address, IP),
121 CONFIG("cluster_interface", cluster_interface, STRING),
122 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
123 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
124 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
125 { NULL, 0, 0, 0 },
126 };
127
128 static char *plugin_functions[] = {
129 NULL,
130 "plugin_pre_auth",
131 "plugin_post_auth",
132 "plugin_packet_rx",
133 "plugin_packet_tx",
134 "plugin_timer",
135 "plugin_new_session",
136 "plugin_kill_session",
137 "plugin_control",
138 "plugin_radius_response",
139 "plugin_become_master",
140 "plugin_new_session_master",
141 };
142
143 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
144
145 // Counters for shutdown sessions
146 static sessiont shut_acct[8192];
147 static sessionidt shut_acct_n = 0;
148
149 tunnelt *tunnel = NULL; // Array of tunnel structures.
150 sessiont *session = NULL; // Array of session structures.
151 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
152 radiust *radius = NULL; // Array of radius structures.
153 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
154 ip_filtert *ip_filters = NULL; // Array of named filters.
155 static controlt *controlfree = 0;
156 struct Tstats *_statistics = NULL;
157 #ifdef RINGBUFFER
158 struct Tringbuffer *ringbuffer = NULL;
159 #endif
160
161 static void cache_ipmap(in_addr_t ip, int s);
162 static void uncache_ipmap(in_addr_t ip);
163 static void free_ip_address(sessionidt s);
164 static void dump_acct_info(int all);
165 static void sighup_handler(int sig);
166 static void sigalrm_handler(int sig);
167 static void sigterm_handler(int sig);
168 static void sigquit_handler(int sig);
169 static void sigchild_handler(int sig);
170 static void read_state(void);
171 static void dump_state(void);
172 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
173 static void update_config(void);
174 static void read_config_file(void);
175 static void initplugins(void);
176 static int add_plugin(char *plugin_name);
177 static int remove_plugin(char *plugin_name);
178 static void plugins_done(void);
179 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
180 static tunnelidt new_tunnel(void);
181 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
182
183 // on slaves, alow BGP to withdraw cleanly before exiting
184 #define QUIT_DELAY 5
185
186 // return internal time (10ths since process startup), set f if given
187 static clockt now(double *f)
188 {
189 struct timeval t;
190 gettimeofday(&t, 0);
191 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
192 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
193 }
194
195 // work out a retry time based on try number
196 // This is a straight bounded exponential backoff.
197 // Maximum re-try time is 32 seconds. (2^5).
198 clockt backoff(uint8_t try)
199 {
200 if (try > 5) try = 5; // max backoff
201 return now(NULL) + 10 * (1 << try);
202 }
203
204
205 //
206 // Log a debug message. Typically called via the LOG macro
207 //
208 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
209 {
210 static char message[65536] = {0};
211 static char message2[65536] = {0};
212 va_list ap;
213
214 #ifdef RINGBUFFER
215 if (ringbuffer)
216 {
217 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
218 ringbuffer->tail = 0;
219 if (ringbuffer->tail == ringbuffer->head)
220 if (++ringbuffer->head >= RINGBUFFER_SIZE)
221 ringbuffer->head = 0;
222
223 ringbuffer->buffer[ringbuffer->tail].level = level;
224 ringbuffer->buffer[ringbuffer->tail].session = s;
225 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
226 va_start(ap, format);
227 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
228 va_end(ap);
229 }
230 #endif
231
232 if (config->debug < level) return;
233
234 va_start(ap, format);
235 if (log_stream)
236 {
237 vsnprintf(message2, 65535, format, ap);
238 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
239 fprintf(log_stream, "%s", message);
240 }
241 else if (syslog_log)
242 {
243 vsnprintf(message2, 65535, format, ap);
244 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
245 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
246 }
247 va_end(ap);
248 }
249
250 void _log_hex(int level, const char *title, const char *data, int maxsize)
251 {
252 int i, j;
253 const uint8_t *d = (const uint8_t *) data;
254
255 if (config->debug < level) return;
256
257 // No support for _log_hex to syslog
258 if (log_stream)
259 {
260 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
261 setvbuf(log_stream, NULL, _IOFBF, 16384);
262
263 for (i = 0; i < maxsize; )
264 {
265 fprintf(log_stream, "%4X: ", i);
266 for (j = i; j < maxsize && j < (i + 16); j++)
267 {
268 fprintf(log_stream, "%02X ", d[j]);
269 if (j == i + 7)
270 fputs(": ", log_stream);
271 }
272
273 for (; j < i + 16; j++)
274 {
275 fputs(" ", log_stream);
276 if (j == i + 7)
277 fputs(": ", log_stream);
278 }
279
280 fputs(" ", log_stream);
281 for (j = i; j < maxsize && j < (i + 16); j++)
282 {
283 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
284 fputc(d[j], log_stream);
285 else
286 fputc('.', log_stream);
287
288 if (j == i + 7)
289 fputs(" ", log_stream);
290 }
291
292 i = j;
293 fputs("\n", log_stream);
294 }
295
296 fflush(log_stream);
297 setbuf(log_stream, NULL);
298 }
299 }
300
301
302 // Add a route
303 //
304 // This adds it to the routing table, advertises it
305 // via BGP if enabled, and stuffs it into the
306 // 'sessionbyip' cache.
307 //
308 // 'ip' and 'mask' must be in _host_ order.
309 //
310 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
311 {
312 struct rtentry r;
313 int i;
314
315 if (!mask) mask = 0xffffffff;
316
317 ip &= mask; // Force the ip to be the first one in the route.
318
319 memset(&r, 0, sizeof(r));
320 r.rt_dev = config->tundevice;
321 r.rt_dst.sa_family = AF_INET;
322 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
323 r.rt_gateway.sa_family = AF_INET;
324 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
325 r.rt_genmask.sa_family = AF_INET;
326 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
327 r.rt_flags = (RTF_UP | RTF_STATIC);
328 if (gw)
329 r.rt_flags |= RTF_GATEWAY;
330 else if (mask == 0xffffffff)
331 r.rt_flags |= RTF_HOST;
332
333 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
334 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
335 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
336
337 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
338 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
339
340 #ifdef BGP
341 if (add)
342 bgp_add_route(htonl(ip), htonl(mask));
343 else
344 bgp_del_route(htonl(ip), htonl(mask));
345 #endif /* BGP */
346
347 // Add/Remove the IPs to the 'sessionbyip' cache.
348 // Note that we add the zero address in the case of
349 // a network route. Roll on CIDR.
350
351 // Note that 's == 0' implies this is the address pool.
352 // We still cache it here, because it will pre-fill
353 // the malloc'ed tree.
354
355 if (s)
356 {
357 if (!add) // Are we deleting a route?
358 s = 0; // Caching the session as '0' is the same as uncaching.
359
360 for (i = ip; (i&mask) == (ip&mask) ; ++i)
361 cache_ipmap(i, s);
362 }
363 }
364
365 //
366 // Set up TUN interface
367 static void inittun(void)
368 {
369 struct ifreq ifr;
370 struct sockaddr_in sin = {0};
371 memset(&ifr, 0, sizeof(ifr));
372 ifr.ifr_flags = IFF_TUN;
373
374 tunfd = open(TUNDEVICE, O_RDWR);
375 if (tunfd < 0)
376 { // fatal
377 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
378 exit(1);
379 }
380 {
381 int flags = fcntl(tunfd, F_GETFL, 0);
382 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
383 }
384 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
385 {
386 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
387 exit(1);
388 }
389 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
390 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
391 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
392
393 sin.sin_family = AF_INET;
394 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
395 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
396
397 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
398 {
399 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
400 exit(1);
401 }
402 /* Bump up the qlen to deal with bursts from the network */
403 ifr.ifr_qlen = 1000;
404 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
405 {
406 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
407 exit(1);
408 }
409 ifr.ifr_flags = IFF_UP;
410 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
411 {
412 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
413 exit(1);
414 }
415 }
416
417 // set up UDP port
418 static void initudp(void)
419 {
420 int on = 1;
421 struct sockaddr_in addr;
422
423 // Tunnel
424 memset(&addr, 0, sizeof(addr));
425 addr.sin_family = AF_INET;
426 addr.sin_port = htons(L2TPPORT);
427 addr.sin_addr.s_addr = config->bind_address;
428 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
429 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
430 {
431 int flags = fcntl(udpfd, F_GETFL, 0);
432 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
433 }
434 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
435 {
436 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
437 exit(1);
438 }
439 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
440
441 // Control
442 memset(&addr, 0, sizeof(addr));
443 addr.sin_family = AF_INET;
444 addr.sin_port = htons(NSCTL_PORT);
445 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
446 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
447 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
448 {
449 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
450 exit(1);
451 }
452 }
453
454 //
455 // Find session by IP, < 1 for not found
456 //
457 // Confusingly enough, this 'ip' must be
458 // in _network_ order. This being the common
459 // case when looking it up from IP packet headers.
460 //
461 // We actually use this cache for two things.
462 // #1. For used IP addresses, this maps to the
463 // session ID that it's used by.
464 // #2. For un-used IP addresses, this maps to the
465 // index into the pool table that contains that
466 // IP address.
467 //
468
469 static int lookup_ipmap(in_addr_t ip)
470 {
471 uint8_t *a = (uint8_t *) &ip;
472 uint8_t **d = (uint8_t **) ip_hash;
473
474 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
475 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
476 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
477
478 return (int) (intptr_t) d[(size_t) *a];
479 }
480
481 sessionidt sessionbyip(in_addr_t ip)
482 {
483 int s = lookup_ipmap(ip);
484 CSTAT(call_sessionbyip);
485
486 if (s > 0 && s < MAXSESSION && session[s].opened)
487 return (sessionidt) s;
488
489 return 0;
490 }
491
492 //
493 // Take an IP address in HOST byte order and
494 // add it to the sessionid by IP cache.
495 //
496 // (It's actually cached in network order)
497 //
498 static void cache_ipmap(in_addr_t ip, int s)
499 {
500 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
501 uint8_t *a = (uint8_t *) &nip;
502 uint8_t **d = (uint8_t **) ip_hash;
503 int i;
504
505 for (i = 0; i < 3; i++)
506 {
507 if (!d[(size_t) a[i]])
508 {
509 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
510 return;
511 }
512
513 d = (uint8_t **) d[(size_t) a[i]];
514 }
515
516 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
517
518 if (s > 0)
519 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
520
521 else if (s == 0)
522 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
523 // else a map to an ip pool index.
524 }
525
526 static void uncache_ipmap(in_addr_t ip)
527 {
528 cache_ipmap(ip, 0); // Assign it to the NULL session.
529 }
530
531 //
532 // CLI list to dump current ipcache.
533 //
534 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
535 {
536 char **d = (char **) ip_hash, **e, **f, **g;
537 int i, j, k, l;
538 int count = 0;
539
540 if (CLI_HELP_REQUESTED)
541 return CLI_HELP_NO_ARGS;
542
543 cli_print(cli, "%7s %s", "Sess#", "IP Address");
544
545 for (i = 0; i < 256; ++i)
546 {
547 if (!d[i])
548 continue;
549 e = (char **) d[i];
550 for (j = 0; j < 256; ++j)
551 {
552 if (!e[j])
553 continue;
554 f = (char **) e[j];
555 for (k = 0; k < 256; ++k)
556 {
557 if (!f[k])
558 continue;
559 g = (char **)f[k];
560 for (l = 0; l < 256; ++l)
561 {
562 if (!g[l])
563 continue;
564 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
565 ++count;
566 }
567 }
568 }
569 }
570 cli_print(cli, "%d entries in cache", count);
571 return CLI_OK;
572 }
573
574
575 // Find session by username, 0 for not found
576 // walled garden users aren't authenticated, so the username is
577 // reasonably useless. Ignore them to avoid incorrect actions
578 //
579 // This is VERY inefficent. Don't call it often. :)
580 //
581 sessionidt sessionbyuser(char *username)
582 {
583 int s;
584 CSTAT(call_sessionbyuser);
585
586 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
587 {
588 if (!session[s].opened)
589 continue;
590
591 if (session[s].walled_garden)
592 continue; // Skip walled garden users.
593
594 if (!strncmp(session[s].user, username, 128))
595 return s;
596
597 }
598 return 0; // Not found.
599 }
600
601 void send_garp(in_addr_t ip)
602 {
603 int s;
604 struct ifreq ifr;
605 uint8_t mac[6];
606
607 s = socket(PF_INET, SOCK_DGRAM, 0);
608 if (s < 0)
609 {
610 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
611 return;
612 }
613 memset(&ifr, 0, sizeof(ifr));
614 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
615 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
616 {
617 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
618 close(s);
619 return;
620 }
621 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
622 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
623 {
624 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
625 close(s);
626 return;
627 }
628 close(s);
629 sendarp(ifr.ifr_ifindex, mac, ip);
630 }
631
632 static sessiont *sessiontbysessionidt(sessionidt s)
633 {
634 if (!s || s >= MAXSESSION) return NULL;
635 return &session[s];
636 }
637
638 static sessionidt sessionidtbysessiont(sessiont *s)
639 {
640 sessionidt val = s-session;
641 if (s < session || val >= MAXSESSION) return 0;
642 return val;
643 }
644
645 // actually send a control message for a specific tunnel
646 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
647 {
648 struct sockaddr_in addr;
649
650 CSTAT(call_tunnelsend);
651
652 if (!t)
653 {
654 static int backtrace_count = 0;
655 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
656 STAT(tunnel_tx_errors);
657 log_backtrace(backtrace_count, 5)
658 return;
659 }
660
661 if (!tunnel[t].ip)
662 {
663 static int backtrace_count = 0;
664 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
665 log_backtrace(backtrace_count, 5)
666 STAT(tunnel_tx_errors);
667 return;
668 }
669
670 memset(&addr, 0, sizeof(addr));
671 addr.sin_family = AF_INET;
672 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
673 addr.sin_port = htons(tunnel[t].port);
674
675 // sequence expected, if sequence in message
676 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
677
678 // If this is a control message, deal with retries
679 if (*buf & 0x80)
680 {
681 tunnel[t].last = time_now; // control message sent
682 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
683 if (tunnel[t].try > 1)
684 {
685 STAT(tunnel_retries);
686 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
687 }
688 }
689
690 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
691 {
692 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
693 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
694 STAT(tunnel_tx_errors);
695 return;
696 }
697
698 LOG_HEX(5, "Send Tunnel Data", buf, l);
699 STAT(tunnel_tx_packets);
700 INC_STAT(tunnel_tx_bytes, l);
701 }
702
703 //
704 // Tiny helper function to write data to
705 // the 'tun' device.
706 //
707 int tun_write(uint8_t * data, int size)
708 {
709 return write(tunfd, data, size);
710 }
711
712 // process outgoing (to tunnel) IP
713 //
714 static void processipout(uint8_t * buf, int len)
715 {
716 sessionidt s;
717 sessiont *sp;
718 tunnelidt t;
719 in_addr_t ip;
720
721 char *data = buf; // Keep a copy of the originals.
722 int size = len;
723
724 uint8_t b[MAXETHER + 20];
725
726 CSTAT(call_processipout);
727
728 if (len < MIN_IP_SIZE)
729 {
730 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
731 STAT(tun_rx_errors);
732 return;
733 }
734 if (len >= MAXETHER)
735 {
736 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
737 STAT(tun_rx_errors);
738 return;
739 }
740
741 // Skip the tun header
742 buf += 4;
743 len -= 4;
744
745 // Got an IP header now
746 if (*(uint8_t *)(buf) >> 4 != 4)
747 {
748 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
749 return;
750 }
751
752 ip = *(uint32_t *)(buf + 16);
753 if (!(s = sessionbyip(ip)))
754 {
755 // Is this a packet for a session that doesn't exist?
756 static int rate = 0; // Number of ICMP packets we've sent this second.
757 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
758
759 if (last != time_now)
760 {
761 last = time_now;
762 rate = 0;
763 }
764
765 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
766 {
767 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
768 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
769 }
770 return;
771 }
772 t = session[s].tunnel;
773 sp = &session[s];
774
775 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
776 if (config->max_packets > 0)
777 {
778 if (sess_local[s].last_packet_out == TIME)
779 {
780 int max = config->max_packets;
781
782 // All packets for throttled sessions are handled by the
783 // master, so further limit by using the throttle rate.
784 // A bit of a kludge, since throttle rate is in kbps,
785 // but should still be generous given our average DSL
786 // packet size is 200 bytes: a limit of 28kbps equates
787 // to around 180 packets per second.
788 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
789 max = sp->throttle_out;
790
791 if (++sess_local[s].packets_out > max)
792 {
793 sess_local[s].packets_dropped++;
794 return;
795 }
796 }
797 else
798 {
799 if (sess_local[s].packets_dropped)
800 {
801 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
802 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
803 sess_local[s].packets_dropped, sess_local[s].packets_out,
804 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
805 sp->user);
806 }
807
808 sess_local[s].last_packet_out = TIME;
809 sess_local[s].packets_out = 1;
810 sess_local[s].packets_dropped = 0;
811 }
812 }
813
814 // run access-list if any
815 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
816 return;
817
818 if (sp->tbf_out)
819 {
820 // Are we throttling this session?
821 if (config->cluster_iam_master)
822 tbf_queue_packet(sp->tbf_out, data, size);
823 else
824 master_throttle_packet(sp->tbf_out, data, size);
825 return;
826 }
827 else if (sp->walled_garden && !config->cluster_iam_master)
828 {
829 // We are walled-gardening this
830 master_garden_packet(s, data, size);
831 return;
832 }
833
834 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
835
836 // Add on L2TP header
837 {
838 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
839 if (!p) return;
840 tunnelsend(b, len + (p-b), t); // send it...
841 }
842
843 // Snooping this session, send it to intercept box
844 if (sp->snoop_ip && sp->snoop_port)
845 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
846
847 sp->cout += len; // byte count
848 sp->total_cout += len; // byte count
849 sp->pout++;
850 udp_tx += len;
851 sess_local[s].cout += len; // To send to master..
852 }
853
854 //
855 // Helper routine for the TBF filters.
856 // Used to send queued data in to the user!
857 //
858 static void send_ipout(sessionidt s, uint8_t *buf, int len)
859 {
860 sessiont *sp;
861 tunnelidt t;
862 in_addr_t ip;
863
864 uint8_t b[MAXETHER + 20];
865
866 if (len < 0 || len > MAXETHER)
867 {
868 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
869 return;
870 }
871
872 // Skip the tun header
873 buf += 4;
874 len -= 4;
875
876 ip = *(in_addr_t *)(buf + 16);
877
878 if (!session[s].ip)
879 return;
880
881 t = session[s].tunnel;
882 sp = &session[s];
883
884 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
885
886 // Add on L2TP header
887 {
888 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
889 if (!p) return;
890 tunnelsend(b, len + (p-b), t); // send it...
891 }
892
893 // Snooping this session.
894 if (sp->snoop_ip && sp->snoop_port)
895 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
896
897 sp->cout += len; // byte count
898 sp->total_cout += len; // byte count
899 sp->pout++;
900 udp_tx += len;
901 sess_local[s].cout += len; // To send to master..
902 }
903
904 // add an AVP (16 bit)
905 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
906 {
907 uint16_t l = (m ? 0x8008 : 0x0008);
908 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
909 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
910 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
911 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
912 c->length += 8;
913 }
914
915 // add an AVP (32 bit)
916 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
917 {
918 uint16_t l = (m ? 0x800A : 0x000A);
919 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
920 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
921 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
922 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
923 c->length += 10;
924 }
925
926 // add an AVP (32 bit)
927 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
928 {
929 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
930 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
931 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
932 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
933 memcpy(c->buf + c->length + 6, val, strlen(val));
934 c->length += 6 + strlen(val);
935 }
936
937 // add a binary AVP
938 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
939 {
940 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
941 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
942 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
943 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
944 memcpy(c->buf + c->length + 6, val, len);
945 c->length += 6 + len;
946 }
947
948 // new control connection
949 static controlt *controlnew(uint16_t mtype)
950 {
951 controlt *c;
952 if (!controlfree)
953 c = malloc(sizeof(controlt));
954 else
955 {
956 c = controlfree;
957 controlfree = c->next;
958 }
959 assert(c);
960 c->next = 0;
961 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
962 c->length = 12;
963 control16(c, 0, mtype, 1);
964 return c;
965 }
966
967 // send zero block if nothing is waiting
968 // (ZLB send).
969 static void controlnull(tunnelidt t)
970 {
971 uint8_t buf[12];
972 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
973 return;
974
975 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
976 *(uint16_t *) (buf + 2) = htons(12); // length
977 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
978 *(uint16_t *) (buf + 6) = htons(0); // session
979 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
980 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
981 tunnelsend(buf, 12, t);
982 }
983
984 // add a control message to a tunnel, and send if within window
985 static void controladd(controlt * c, tunnelidt t, sessionidt s)
986 {
987 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
988 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
989 *(uint16_t *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
990 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
991 tunnel[t].ns++; // advance sequence
992 // link in message in to queue
993 if (tunnel[t].controlc)
994 tunnel[t].controle->next = c;
995 else
996 tunnel[t].controls = c;
997
998 tunnel[t].controle = c;
999 tunnel[t].controlc++;
1000
1001 // send now if space in window
1002 if (tunnel[t].controlc <= tunnel[t].window)
1003 {
1004 tunnel[t].try = 0; // first send
1005 tunnelsend(c->buf, c->length, t);
1006 }
1007 }
1008
1009 //
1010 // Throttle or Unthrottle a session
1011 //
1012 // Throttle the data from/to through a session to no more than
1013 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1014 // user).
1015 //
1016 // If either value is -1, the current value is retained for that
1017 // direction.
1018 //
1019 void throttle_session(sessionidt s, int rate_in, int rate_out)
1020 {
1021 if (!session[s].opened)
1022 return; // No-one home.
1023
1024 if (!*session[s].user)
1025 return; // User not logged in
1026
1027 if (rate_in >= 0)
1028 {
1029 int bytes = rate_in * 1024 / 8; // kbits to bytes
1030 if (session[s].tbf_in)
1031 free_tbf(session[s].tbf_in);
1032
1033 if (rate_in > 0)
1034 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1035 else
1036 session[s].tbf_in = 0;
1037
1038 session[s].throttle_in = rate_in;
1039 }
1040
1041 if (rate_out >= 0)
1042 {
1043 int bytes = rate_out * 1024 / 8;
1044 if (session[s].tbf_out)
1045 free_tbf(session[s].tbf_out);
1046
1047 if (rate_out > 0)
1048 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1049 else
1050 session[s].tbf_out = 0;
1051
1052 session[s].throttle_out = rate_out;
1053 }
1054 }
1055
1056 // add/remove filters from session (-1 = no change)
1057 void filter_session(sessionidt s, int filter_in, int filter_out)
1058 {
1059 if (!session[s].opened)
1060 return; // No-one home.
1061
1062 if (!*session[s].user)
1063 return; // User not logged in
1064
1065 // paranoia
1066 if (filter_in > MAXFILTER) filter_in = -1;
1067 if (filter_out > MAXFILTER) filter_out = -1;
1068 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1069 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1070
1071 if (filter_in >= 0)
1072 {
1073 if (session[s].filter_in)
1074 ip_filters[session[s].filter_in - 1].used--;
1075
1076 if (filter_in > 0)
1077 ip_filters[filter_in - 1].used++;
1078
1079 session[s].filter_in = filter_in;
1080 }
1081
1082 if (filter_out >= 0)
1083 {
1084 if (session[s].filter_out)
1085 ip_filters[session[s].filter_out - 1].used--;
1086
1087 if (filter_out > 0)
1088 ip_filters[filter_out - 1].used++;
1089
1090 session[s].filter_out = filter_out;
1091 }
1092 }
1093
1094 // start tidy shutdown of session
1095 void sessionshutdown(sessionidt s, char *reason)
1096 {
1097 int walled_garden = session[s].walled_garden;
1098
1099
1100 CSTAT(call_sessionshutdown);
1101
1102 if (!session[s].opened)
1103 {
1104 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1105 return; // not a live session
1106 }
1107
1108 if (!session[s].die)
1109 {
1110 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1111 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1112 run_plugins(PLUGIN_KILL_SESSION, &data);
1113 }
1114
1115 if (session[s].ip && !walled_garden && !session[s].die)
1116 {
1117 // RADIUS Stop message
1118 uint16_t r = session[s].radius;
1119 if (!r)
1120 {
1121 if (!(r = radiusnew(s)))
1122 {
1123 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1124 }
1125 else
1126 {
1127 int n;
1128 for (n = 0; n < 15; n++)
1129 radius[r].auth[n] = rand();
1130 }
1131 }
1132
1133 if (r && radius[r].state != RADIUSSTOP)
1134 radiussend(r, RADIUSSTOP); // stop, if not already trying
1135
1136 // Save counters to dump to accounting file
1137 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1138 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1139 }
1140
1141 if (session[s].ip)
1142 { // IP allocated, clear and unroute
1143 int r;
1144 int routed = 0;
1145 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1146 {
1147 if ((session[s].ip & session[s].route[r].mask) ==
1148 (session[s].route[r].ip & session[s].route[r].mask))
1149 routed++;
1150
1151 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1152 session[s].route[r].ip = 0;
1153 }
1154
1155 if (session[s].ip_pool_index == -1) // static ip
1156 {
1157 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1158 session[s].ip = 0;
1159 }
1160 else
1161 free_ip_address(s);
1162 }
1163
1164 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1165 throttle_session(s, 0, 0);
1166
1167 { // Send CDN
1168 controlt *c = controlnew(14); // sending CDN
1169 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1170 control16(c, 14, s, 1); // assigned session (our end)
1171 controladd(c, session[s].tunnel, s); // send the message
1172 }
1173
1174 if (!session[s].die)
1175 session[s].die = TIME + 150; // Clean up in 15 seconds
1176
1177 // update filter refcounts
1178 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1179 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1180
1181 cluster_send_session(s);
1182 }
1183
1184 void sendipcp(tunnelidt t, sessionidt s)
1185 {
1186 uint8_t buf[MAXCONTROL];
1187 uint16_t r = session[s].radius;
1188 uint8_t *q;
1189
1190 CSTAT(call_sendipcp);
1191
1192 if (!r)
1193 r = radiusnew(s);
1194
1195 if (!r)
1196 {
1197 sessionshutdown(s, "No free RADIUS sessions for IPCP");
1198 return;
1199 }
1200
1201 if (radius[r].state != RADIUSIPCP)
1202 {
1203 radius[r].state = RADIUSIPCP;
1204 radius[r].try = 0;
1205 }
1206
1207 radius[r].retry = backoff(radius[r].try++);
1208 if (radius[r].try > 10)
1209 {
1210 radiusclear(r, s); // Clear radius session.
1211 sessionshutdown(s, "No reply on IPCP");
1212 return;
1213 }
1214
1215 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1216 if (!q) return;
1217
1218 *q = ConfigReq;
1219 q[1] = r >> RADIUS_SHIFT; // ID, dont care, we only send one type of request
1220 *(uint16_t *) (q + 2) = htons(10);
1221 q[4] = 3;
1222 q[5] = 6;
1223 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1224 config->bind_address ? config->bind_address :
1225 my_address; // send my IP
1226
1227 tunnelsend(buf, 10 + (q - buf), t); // send it
1228 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1229 }
1230
1231 static void sessionclear(sessionidt s)
1232 {
1233 memset(&session[s], 0, sizeof(session[s]));
1234 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1235 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1236
1237 session[s].tunnel = T_FREE; // Mark it as free.
1238 session[s].next = sessionfree;
1239 sessionfree = s;
1240 }
1241
1242 // kill a session now
1243 void sessionkill(sessionidt s, char *reason)
1244 {
1245
1246 CSTAT(call_sessionkill);
1247
1248 if (!session[s].opened) // not alive
1249 return;
1250
1251 if (session[s].next)
1252 {
1253 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1254 return;
1255 }
1256
1257 session[s].die = TIME;
1258 sessionshutdown(s, reason); // close radius/routes, etc.
1259 if (session[s].radius)
1260 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1261
1262 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1263 sessionclear(s);
1264 cluster_send_session(s);
1265 }
1266
1267 static void tunnelclear(tunnelidt t)
1268 {
1269 if (!t) return;
1270 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1271 tunnel[t].state = TUNNELFREE;
1272 }
1273
1274 // kill a tunnel now
1275 static void tunnelkill(tunnelidt t, char *reason)
1276 {
1277 sessionidt s;
1278 controlt *c;
1279
1280 CSTAT(call_tunnelkill);
1281
1282 tunnel[t].state = TUNNELDIE;
1283
1284 // free control messages
1285 while ((c = tunnel[t].controls))
1286 {
1287 controlt * n = c->next;
1288 tunnel[t].controls = n;
1289 tunnel[t].controlc--;
1290 c->next = controlfree;
1291 controlfree = c;
1292 }
1293 // kill sessions
1294 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1295 if (session[s].tunnel == t)
1296 sessionkill(s, reason);
1297
1298 // free tunnel
1299 tunnelclear(t);
1300 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1301 cli_tunnel_actions[s].action = 0;
1302 cluster_send_tunnel(t);
1303 }
1304
1305 // shut down a tunnel cleanly
1306 static void tunnelshutdown(tunnelidt t, char *reason)
1307 {
1308 sessionidt s;
1309
1310 CSTAT(call_tunnelshutdown);
1311
1312 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1313 {
1314 // never set up, can immediately kill
1315 tunnelkill(t, reason);
1316 return;
1317 }
1318 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1319
1320 // close session
1321 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1322 if (session[s].tunnel == t)
1323 sessionshutdown(s, reason);
1324
1325 tunnel[t].state = TUNNELDIE;
1326 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1327 cluster_send_tunnel(t);
1328 // TBA - should we wait for sessions to stop?
1329 { // Send StopCCN
1330 controlt *c = controlnew(4); // sending StopCCN
1331 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message)
1332 control16(c, 9, t, 1); // assigned tunnel (our end)
1333 controladd(c, t, 0); // send the message
1334 }
1335 }
1336
1337 // read and process packet on tunnel (UDP)
1338 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1339 {
1340 char *chapresponse = NULL;
1341 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1342 uint8_t *p = buf + 2;
1343
1344
1345 CSTAT(call_processudp);
1346
1347 udp_rx += len;
1348 udp_rx_pkt++;
1349 LOG_HEX(5, "UDP Data", buf, len);
1350 STAT(tunnel_rx_packets);
1351 INC_STAT(tunnel_rx_bytes, len);
1352 if (len < 6)
1353 {
1354 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1355 STAT(tunnel_rx_errors);
1356 return;
1357 }
1358 if ((buf[1] & 0x0F) != 2)
1359 {
1360 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1361 STAT(tunnel_rx_errors);
1362 return;
1363 }
1364 if (*buf & 0x40)
1365 { // length
1366 l = ntohs(*(uint16_t *) p);
1367 p += 2;
1368 }
1369 t = ntohs(*(uint16_t *) p);
1370 p += 2;
1371 s = ntohs(*(uint16_t *) p);
1372 p += 2;
1373 if (s >= MAXSESSION)
1374 {
1375 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1376 STAT(tunnel_rx_errors);
1377 return;
1378 }
1379 if (t >= MAXTUNNEL)
1380 {
1381 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1382 STAT(tunnel_rx_errors);
1383 return;
1384 }
1385 if (*buf & 0x08)
1386 { // ns/nr
1387 ns = ntohs(*(uint16_t *) p);
1388 p += 2;
1389 nr = ntohs(*(uint16_t *) p);
1390 p += 2;
1391 }
1392 if (*buf & 0x02)
1393 { // offset
1394 uint16_t o = ntohs(*(uint16_t *) p);
1395 p += o + 2;
1396 }
1397 if ((p - buf) > l)
1398 {
1399 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1400 STAT(tunnel_rx_errors);
1401 return;
1402 }
1403 l -= (p - buf);
1404 if (*buf & 0x80)
1405 { // control
1406 uint16_t message = 0xFFFF; // message type
1407 uint8_t fatal = 0;
1408 uint8_t mandatorymessage = 0;
1409 uint8_t chap = 0; // if CHAP being used
1410 uint16_t asession = 0; // assigned session
1411 uint32_t amagic = 0; // magic number
1412 uint8_t aflags = 0; // flags from last LCF
1413 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1414 int requestchap = 0; // do we request PAP instead of original CHAP request?
1415 char called[MAXTEL] = ""; // called number
1416 char calling[MAXTEL] = ""; // calling number
1417
1418 if (!config->cluster_iam_master)
1419 {
1420 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1421 return;
1422 }
1423
1424 if ((*buf & 0xCA) != 0xC8)
1425 {
1426 LOG(1, s, t, "Bad control header %02X\n", *buf);
1427 STAT(tunnel_rx_errors);
1428 return;
1429 }
1430
1431 // check for duplicate tunnel open message
1432 if (!t && ns == 0)
1433 {
1434 int i;
1435
1436 //
1437 // Is this a duplicate of the first packet? (SCCRQ)
1438 //
1439 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1440 {
1441 if (tunnel[i].state != TUNNELOPENING ||
1442 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1443 tunnel[i].port != ntohs(addr->sin_port) )
1444 continue;
1445 t = i;
1446 LOG(3, s, t, "Duplicate SCCRQ?\n");
1447 break;
1448 }
1449 }
1450
1451 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1452 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1453
1454 // if no tunnel specified, assign one
1455 if (!t)
1456 {
1457 if (!(t = new_tunnel()))
1458 {
1459 LOG(1, 0, 0, "No more tunnels\n");
1460 STAT(tunnel_overflow);
1461 return;
1462 }
1463 tunnelclear(t);
1464 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1465 tunnel[t].port = ntohs(addr->sin_port);
1466 tunnel[t].window = 4; // default window
1467 STAT(tunnel_created);
1468 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1469 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1470 }
1471
1472 // If the 'ns' just received is not the 'nr' we're
1473 // expecting, just send an ack and drop it.
1474 //
1475 // if 'ns' is less, then we got a retransmitted packet.
1476 // if 'ns' is greater than missed a packet. Either way
1477 // we should ignore it.
1478 if (ns != tunnel[t].nr)
1479 {
1480 // is this the sequence we were expecting?
1481 STAT(tunnel_rx_errors);
1482 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1483 t, ns, tunnel[t].nr);
1484
1485 if (l) // Is this not a ZLB?
1486 controlnull(t);
1487 return;
1488 }
1489
1490 // This is used to time out old tunnels
1491 tunnel[t].lastrec = time_now;
1492
1493 // check sequence of this message
1494 {
1495 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1496 // some to clear maybe?
1497 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1498 {
1499 controlt *c = tunnel[t].controls;
1500 tunnel[t].controls = c->next;
1501 tunnel[t].controlc--;
1502 c->next = controlfree;
1503 controlfree = c;
1504 skip--;
1505 tunnel[t].try = 0; // we have progress
1506 }
1507
1508 // receiver advance (do here so quoted correctly in any sends below)
1509 if (l) tunnel[t].nr = (ns + 1);
1510 if (skip < 0) skip = 0;
1511 if (skip < tunnel[t].controlc)
1512 {
1513 // some control packets can now be sent that were previous stuck out of window
1514 int tosend = tunnel[t].window - skip;
1515 controlt *c = tunnel[t].controls;
1516 while (c && skip)
1517 {
1518 c = c->next;
1519 skip--;
1520 }
1521 while (c && tosend)
1522 {
1523 tunnel[t].try = 0; // first send
1524 tunnelsend(c->buf, c->length, t);
1525 c = c->next;
1526 tosend--;
1527 }
1528 }
1529 if (!tunnel[t].controlc)
1530 tunnel[t].retry = 0; // caught up
1531 }
1532 if (l)
1533 { // if not a null message
1534 // process AVPs
1535 while (l && !(fatal & 0x80))
1536 {
1537 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1538 uint8_t *b = p;
1539 uint8_t flags = *p;
1540 uint16_t mtype;
1541 p += n; // next
1542 if (l < n)
1543 {
1544 LOG(1, s, t, "Invalid length in AVP\n");
1545 STAT(tunnel_rx_errors);
1546 fatal = flags;
1547 return;
1548 }
1549 l -= n;
1550 if (flags & 0x40)
1551 {
1552 // handle hidden AVPs
1553 if (!*config->l2tpsecret)
1554 {
1555 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
1556 fatal = flags;
1557 continue;
1558 }
1559 if (!session[s].random_vector_length)
1560 {
1561 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
1562 fatal = flags;
1563 continue;
1564 }
1565 LOG(4, s, t, "Hidden AVP\n");
1566 // Unhide the AVP
1567 n = unhide_avp(b, t, s, n);
1568 if (n == 0)
1569 {
1570 fatal = flags;
1571 continue;
1572 }
1573 }
1574 if (*b & 0x3C)
1575 {
1576 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1577 fatal = flags;
1578 continue; // next
1579 }
1580 b += 2;
1581 if (*(uint16_t *) (b))
1582 {
1583 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1584 fatal = flags;
1585 continue; // next
1586 }
1587 b += 2;
1588 mtype = ntohs(*(uint16_t *) (b));
1589 b += 2;
1590 n -= 6;
1591
1592 LOG(4, s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1593 switch (mtype)
1594 {
1595 case 0: // message type
1596 message = ntohs(*(uint16_t *) b);
1597 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_types[message]);
1598 mandatorymessage = flags;
1599 break;
1600 case 1: // result code
1601 {
1602 uint16_t rescode = ntohs(*(uint16_t *) b);
1603 const char* resdesc = "(unknown)";
1604 if (message == 4)
1605 { /* StopCCN */
1606 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1607 resdesc = stopccn_result_codes[rescode];
1608 }
1609 else if (message == 14)
1610 { /* CDN */
1611 if (rescode <= MAX_CDN_RESULT_CODE)
1612 resdesc = cdn_result_codes[rescode];
1613 }
1614
1615 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
1616 if (n >= 4)
1617 {
1618 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
1619 const char* errdesc = "(unknown)";
1620 if (errcode <= MAX_ERROR_CODE)
1621 errdesc = error_codes[errcode];
1622 LOG(4, s, t, " Error Code %d: %s\n", errcode, errdesc);
1623 }
1624 if (n > 4)
1625 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
1626
1627 break;
1628 }
1629 break;
1630 case 2: // protocol version
1631 {
1632 version = ntohs(*(uint16_t *) (b));
1633 LOG(4, s, t, " Protocol version = %d\n", version);
1634 if (version && version != 0x0100)
1635 { // allow 0.0 and 1.0
1636 LOG(1, s, t, " Bad protocol version %04X\n", version);
1637 fatal = flags;
1638 continue; // next
1639 }
1640 }
1641 break;
1642 case 3: // framing capabilities
1643 // LOG(4, s, t, "Framing capabilities\n");
1644 break;
1645 case 4: // bearer capabilities
1646 // LOG(4, s, t, "Bearer capabilities\n");
1647 break;
1648 case 5: // tie breaker
1649 // We never open tunnels, so we don't care about tie breakers
1650 // LOG(4, s, t, "Tie breaker\n");
1651 continue;
1652 case 6: // firmware revision
1653 // LOG(4, s, t, "Firmware revision\n");
1654 break;
1655 case 7: // host name
1656 memset(tunnel[t].hostname, 0, 128);
1657 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1658 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1659 // TBA - to send to RADIUS
1660 break;
1661 case 8: // vendor name
1662 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1663 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1664 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1665 break;
1666 case 9: // assigned tunnel
1667 tunnel[t].far = ntohs(*(uint16_t *) (b));
1668 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1669 break;
1670 case 10: // rx window
1671 tunnel[t].window = ntohs(*(uint16_t *) (b));
1672 if (!tunnel[t].window)
1673 tunnel[t].window = 1; // window of 0 is silly
1674 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
1675 break;
1676 case 11: // Challenge
1677 {
1678 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
1679 build_chap_response(b, 2, n, &chapresponse);
1680 }
1681 break;
1682 case 13: // Response
1683 // Why did they send a response? We never challenge.
1684 LOG(2, s, t, " received unexpected challenge response\n");
1685 break;
1686
1687 case 14: // assigned session
1688 asession = session[s].far = ntohs(*(uint16_t *) (b));
1689 LOG(4, s, t, " assigned session = %d\n", asession);
1690 break;
1691 case 15: // call serial number
1692 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
1693 break;
1694 case 18: // bearer type
1695 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
1696 // TBA - for RADIUS
1697 break;
1698 case 19: // framing type
1699 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
1700 // TBA
1701 break;
1702 case 21: // called number
1703 memset(called, 0, MAXTEL);
1704 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1705 LOG(4, s, t, " Called <%s>\n", called);
1706 break;
1707 case 22: // calling number
1708 memset(calling, 0, MAXTEL);
1709 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1710 LOG(4, s, t, " Calling <%s>\n", calling);
1711 break;
1712 case 23: // subtype
1713 break;
1714 case 24: // tx connect speed
1715 if (n == 4)
1716 {
1717 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
1718 }
1719 else
1720 {
1721 // AS5300s send connect speed as a string
1722 char tmp[30] = {0};
1723 memcpy(tmp, b, (n >= 30) ? 30 : n);
1724 session[s].tx_connect_speed = atol(tmp);
1725 }
1726 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
1727 break;
1728 case 38: // rx connect speed
1729 if (n == 4)
1730 {
1731 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
1732 }
1733 else
1734 {
1735 // AS5300s send connect speed as a string
1736 char tmp[30] = {0};
1737 memcpy(tmp, b, (n >= 30) ? 30 : n);
1738 session[s].rx_connect_speed = atol(tmp);
1739 }
1740 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
1741 break;
1742 case 25: // Physical Channel ID
1743 {
1744 uint32_t tmp = ntohl(*(uint32_t *) b);
1745 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
1746 break;
1747 }
1748 case 29: // Proxy Authentication Type
1749 {
1750 uint16_t authtype = ntohs(*(uint16_t *)b);
1751 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", authtype, authtypes[authtype]);
1752 requestchap = (authtype == 2);
1753 break;
1754 }
1755 case 30: // Proxy Authentication Name
1756 {
1757 char authname[64] = {0};
1758 memcpy(authname, b, (n > 63) ? 63 : n);
1759 LOG(4, s, t, " Proxy Auth Name (%s)\n",
1760 authname);
1761 break;
1762 }
1763 case 31: // Proxy Authentication Challenge
1764 {
1765 memcpy(radius[session[s].radius].auth, b, 16);
1766 LOG(4, s, t, " Proxy Auth Challenge\n");
1767 break;
1768 }
1769 case 32: // Proxy Authentication ID
1770 {
1771 uint16_t authid = ntohs(*(uint16_t *)(b));
1772 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
1773 if (session[s].radius)
1774 radius[session[s].radius].id = authid;
1775 break;
1776 }
1777 case 33: // Proxy Authentication Response
1778 {
1779 char authresp[64] = {0};
1780 memcpy(authresp, b, (n > 63) ? 63 : n);
1781 LOG(4, s, t, " Proxy Auth Response\n");
1782 break;
1783 }
1784 case 27: // last send lcp
1785 { // find magic number
1786 uint8_t *p = b, *e = p + n;
1787 while (p + 1 < e && p[1] && p + p[1] <= e)
1788 {
1789 if (*p == 5 && p[1] == 6) // Magic-Number
1790 amagic = ntohl(*(uint32_t *) (p + 2));
1791 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
1792 chap = 1;
1793 else if (*p == 7) // Protocol-Field-Compression
1794 aflags |= SESSIONPFC;
1795 else if (*p == 8) // Address-and-Control-Field-Compression
1796 aflags |= SESSIONACFC;
1797 p += p[1];
1798 }
1799 }
1800 break;
1801 case 28: // last recv lcp confreq
1802 break;
1803 case 26: // Initial Received LCP CONFREQ
1804 break;
1805 case 39: // seq required - we control it as an LNS anyway...
1806 break;
1807 case 36: // Random Vector
1808 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
1809 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1810 memcpy(session[s].random_vector, b, n);
1811 session[s].random_vector_length = n;
1812 break;
1813 default:
1814 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
1815 fatal = flags;
1816 continue; // next
1817 }
1818 }
1819 // process message
1820 if (fatal & 0x80)
1821 tunnelshutdown(t, "Unknown Mandatory AVP");
1822 else
1823 switch (message)
1824 {
1825 case 1: // SCCRQ - Start Control Connection Request
1826 {
1827 controlt *c = controlnew(2); // sending SCCRP
1828 control16(c, 2, version, 1); // protocol version
1829 control32(c, 3, 3, 1); // framing
1830 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1831 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1832 control16(c, 9, t, 1); // assigned tunnel
1833 controladd(c, t, s); // send the resply
1834 }
1835 tunnel[t].state = TUNNELOPENING;
1836 break;
1837 case 2: // SCCRP
1838 tunnel[t].state = TUNNELOPEN;
1839 break;
1840 case 3: // SCCN
1841 tunnel[t].state = TUNNELOPEN;
1842 controlnull(t); // ack
1843 break;
1844 case 4: // StopCCN
1845 controlnull(t); // ack
1846 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1847 tunnelkill(t, "Stopped"); // Immediately force everything dead
1848 break;
1849 case 6: // HELLO
1850 controlnull(t); // simply ACK
1851 break;
1852 case 7: // OCRQ
1853 // TBA
1854 break;
1855 case 8: // OCRO
1856 // TBA
1857 break;
1858 case 9: // OCCN
1859 // TBA
1860 break;
1861 case 10: // ICRQ
1862 if (!sessionfree)
1863 {
1864 STAT(session_overflow);
1865 LOG(1, 0, t, "No free sessions\n");
1866 return;
1867 }
1868 else
1869 {
1870 uint16_t r;
1871 controlt *c;
1872
1873 s = sessionfree;
1874 sessionfree = session[s].next;
1875 memset(&session[s], 0, sizeof(session[s]));
1876
1877 if (s > config->cluster_highest_sessionid)
1878 config->cluster_highest_sessionid = s;
1879
1880 // make a RADIUS session
1881 if (!(r = radiusnew(s)))
1882 {
1883 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
1884 sessionclear(s);
1885 return;
1886 }
1887
1888 c = controlnew(11); // sending ICRP
1889 session[s].id = sessionid++;
1890 session[s].opened = time_now;
1891 session[s].tunnel = t;
1892 session[s].far = asession;
1893 session[s].last_packet = time_now;
1894 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1895 control16(c, 14, s, 1); // assigned session
1896 controladd(c, t, s); // send the reply
1897 {
1898 // Generate a random challenge
1899 int n;
1900 for (n = 0; n < 15; n++)
1901 radius[r].auth[n] = rand();
1902 }
1903 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1904 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1905 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1906 STAT(session_created);
1907 }
1908 break;
1909 case 11: // ICRP
1910 // TBA
1911 break;
1912 case 12: // ICCN
1913 if (amagic == 0) amagic = time_now;
1914 session[s].magic = amagic; // set magic number
1915 session[s].l2tp_flags = aflags; // set flags received
1916 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
1917 controlnull(t); // ack
1918 // In CHAP state, request PAP instead
1919 if (requestchap)
1920 initlcp(t, s);
1921 break;
1922 case 14: // CDN
1923 controlnull(t); // ack
1924 sessionshutdown(s, "Closed (Received CDN)");
1925 break;
1926 case 0xFFFF:
1927 LOG(1, s, t, "Missing message type\n");
1928 break;
1929 default:
1930 STAT(tunnel_rx_errors);
1931 if (mandatorymessage & 0x80)
1932 tunnelshutdown(t, "Unknown message");
1933 else
1934 LOG(1, s, t, "Unknown message type %d\n", message);
1935 break;
1936 }
1937 if (chapresponse) free(chapresponse);
1938 cluster_send_tunnel(t);
1939 }
1940 else
1941 {
1942 LOG(4, s, t, " Got a ZLB ack\n");
1943 }
1944 }
1945 else
1946 { // data
1947 uint16_t prot;
1948
1949 LOG_HEX(5, "Receive Tunnel Data", p, l);
1950 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1951 { // HDLC address header, discard
1952 p += 2;
1953 l -= 2;
1954 }
1955 if (l < 2)
1956 {
1957 LOG(1, s, t, "Short ppp length %d\n", l);
1958 STAT(tunnel_rx_errors);
1959 return;
1960 }
1961 if (*p & 1)
1962 {
1963 prot = *p++;
1964 l--;
1965 }
1966 else
1967 {
1968 prot = ntohs(*(uint16_t *) p);
1969 p += 2;
1970 l -= 2;
1971 }
1972
1973 if (s && !session[s].opened) // Is something wrong??
1974 {
1975 if (!config->cluster_iam_master)
1976 {
1977 // Pass it off to the master to deal with..
1978 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1979 return;
1980 }
1981
1982 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
1983 STAT(tunnel_rx_errors);
1984 return;
1985 }
1986
1987 if (prot == PPPPAP)
1988 {
1989 session[s].last_packet = time_now;
1990 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1991 processpap(t, s, p, l);
1992 }
1993 else if (prot == PPPCHAP)
1994 {
1995 session[s].last_packet = time_now;
1996 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1997 processchap(t, s, p, l);
1998 }
1999 else if (prot == PPPLCP)
2000 {
2001 session[s].last_packet = time_now;
2002 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2003 processlcp(t, s, p, l);
2004 }
2005 else if (prot == PPPIPCP)
2006 {
2007 session[s].last_packet = time_now;
2008 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2009 processipcp(t, s, p, l);
2010 }
2011 else if (prot == PPPCCP)
2012 {
2013 session[s].last_packet = time_now;
2014 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2015 processccp(t, s, p, l);
2016 }
2017 else if (prot == PPPIP)
2018 {
2019 if (session[s].die)
2020 {
2021 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2022 return; // closing session, PPP not processed
2023 }
2024
2025 session[s].last_packet = time_now;
2026 if (session[s].walled_garden && !config->cluster_iam_master)
2027 {
2028 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2029 return;
2030 }
2031
2032 processipin(t, s, p, l);
2033 }
2034 else
2035 {
2036 STAT(tunnel_rx_errors);
2037 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2038 }
2039 }
2040 }
2041
2042 // read and process packet on tun
2043 static void processtun(uint8_t * buf, int len)
2044 {
2045 LOG_HEX(5, "Receive TUN Data", buf, len);
2046 STAT(tun_rx_packets);
2047 INC_STAT(tun_rx_bytes, len);
2048
2049 CSTAT(call_processtun);
2050
2051 eth_rx_pkt++;
2052 eth_rx += len;
2053 if (len < 22)
2054 {
2055 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2056 STAT(tun_rx_errors);
2057 return;
2058 }
2059
2060 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IP
2061 processipout(buf, len);
2062 // Else discard.
2063 }
2064
2065 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2066 // that we look at the whole of the tunnel, radius and session tables
2067 // every second
2068 static void regular_cleanups(double period)
2069 {
2070 // Next tunnel, radius and session to check for actions on.
2071 static tunnelidt t = 0;
2072 static int r = 0;
2073 static sessionidt s = 0;
2074
2075 int t_actions = 0;
2076 int r_actions = 0;
2077 int s_actions = 0;
2078
2079 int t_slice;
2080 int r_slice;
2081 int s_slice;
2082
2083 int i;
2084 int a;
2085
2086 // divide up tables into slices based on the last run
2087 t_slice = config->cluster_highest_tunnelid * period;
2088 r_slice = (MAXRADIUS - 1) * period;
2089 s_slice = config->cluster_highest_sessionid * period;
2090
2091 if (t_slice < 1)
2092 t_slice = 1;
2093 else if (t_slice > config->cluster_highest_tunnelid)
2094 t_slice = config->cluster_highest_tunnelid;
2095
2096 if (r_slice < 1)
2097 r_slice = 1;
2098 else if (r_slice > (MAXRADIUS - 1))
2099 r_slice = MAXRADIUS - 1;
2100
2101 if (s_slice < 1)
2102 s_slice = 1;
2103 else if (s_slice > config->cluster_highest_sessionid)
2104 s_slice = config->cluster_highest_sessionid;
2105
2106 LOG(5, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2107
2108 for (i = 0; i < t_slice; i++)
2109 {
2110 t++;
2111 if (t > config->cluster_highest_tunnelid)
2112 t = 1;
2113
2114 // check for expired tunnels
2115 if (tunnel[t].die && tunnel[t].die <= TIME)
2116 {
2117 STAT(tunnel_timeout);
2118 tunnelkill(t, "Expired");
2119 t_actions++;
2120 continue;
2121 }
2122 // check for message resend
2123 if (tunnel[t].retry && tunnel[t].controlc)
2124 {
2125 // resend pending messages as timeout on reply
2126 if (tunnel[t].retry <= TIME)
2127 {
2128 controlt *c = tunnel[t].controls;
2129 uint8_t w = tunnel[t].window;
2130 tunnel[t].try++; // another try
2131 if (tunnel[t].try > 5)
2132 tunnelkill(t, "Timeout on control message"); // game over
2133 else
2134 while (c && w--)
2135 {
2136 tunnelsend(c->buf, c->length, t);
2137 c = c->next;
2138 }
2139
2140 t_actions++;
2141 }
2142 }
2143 // Send hello
2144 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2145 {
2146 controlt *c = controlnew(6); // sending HELLO
2147 controladd(c, t, 0); // send the message
2148 LOG(3, 0, t, "Sending HELLO message\n");
2149 t_actions++;
2150 }
2151
2152 // Check for tunnel changes requested from the CLI
2153 if ((a = cli_tunnel_actions[t].action))
2154 {
2155 cli_tunnel_actions[t].action = 0;
2156 if (a & CLI_TUN_KILL)
2157 {
2158 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2159 tunnelshutdown(t, "Requested by administrator");
2160 t_actions++;
2161 }
2162 }
2163 }
2164
2165 for (i = 0; i < r_slice; i++)
2166 {
2167 r++;
2168 if (r >= MAXRADIUS)
2169 r = 1;
2170
2171 if (!radius[r].state)
2172 continue;
2173
2174 if (radius[r].retry <= TIME)
2175 {
2176 radiusretry(r);
2177 r_actions++;
2178 }
2179 }
2180
2181 for (i = 0; i < s_slice; i++)
2182 {
2183 s++;
2184 if (s > config->cluster_highest_sessionid)
2185 s = 1;
2186
2187 if (!session[s].opened) // Session isn't in use
2188 continue;
2189
2190 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2191 {
2192 // IPCP has not completed yet. Resend
2193 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2194 sendipcp(session[s].tunnel, s);
2195 s_actions++;
2196 }
2197
2198 // check for expired sessions
2199 if (session[s].die && session[s].die <= TIME)
2200 {
2201 sessionkill(s, "Expired");
2202 s_actions++;
2203 continue;
2204 }
2205
2206 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2207 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2208 {
2209 sessionshutdown(s, "No response to LCP ECHO requests");
2210 STAT(session_timeout);
2211 s_actions++;
2212 continue;
2213 }
2214
2215 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2216 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2217 {
2218 uint8_t b[MAXCONTROL] = {0};
2219
2220 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2221 if (!q) continue;
2222
2223 *q = EchoReq;
2224 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2225 *(uint16_t *)(q + 2) = htons(8); // Length
2226 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2227
2228 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2229 (int)(time_now - session[s].last_packet));
2230 tunnelsend(b, 24, session[s].tunnel); // send it
2231 s_actions++;
2232 }
2233
2234 // Check for actions requested from the CLI
2235 if ((a = cli_session_actions[s].action))
2236 {
2237 int send = 0;
2238
2239 cli_session_actions[s].action = 0;
2240 if (a & CLI_SESS_KILL)
2241 {
2242 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2243 sessionshutdown(s, "Requested by administrator");
2244 a = 0; // dead, no need to check for other actions
2245 s_actions++;
2246 }
2247
2248 if (a & CLI_SESS_NOSNOOP)
2249 {
2250 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2251 session[s].snoop_ip = 0;
2252 session[s].snoop_port = 0;
2253 s_actions++;
2254 send++;
2255 }
2256 else if (a & CLI_SESS_SNOOP)
2257 {
2258 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2259 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2260 cli_session_actions[s].snoop_port);
2261
2262 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2263 session[s].snoop_port = cli_session_actions[s].snoop_port;
2264 s_actions++;
2265 send++;
2266 }
2267
2268 if (a & CLI_SESS_NOTHROTTLE)
2269 {
2270 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2271 throttle_session(s, 0, 0);
2272 s_actions++;
2273 send++;
2274 }
2275 else if (a & CLI_SESS_THROTTLE)
2276 {
2277 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2278 cli_session_actions[s].throttle_in,
2279 cli_session_actions[s].throttle_out);
2280
2281 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2282 s_actions++;
2283 send++;
2284 }
2285
2286 if (a & CLI_SESS_NOFILTER)
2287 {
2288 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2289 filter_session(s, 0, 0);
2290 s_actions++;
2291 send++;
2292 }
2293 else if (a & CLI_SESS_FILTER)
2294 {
2295 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2296 cli_session_actions[s].filter_in,
2297 cli_session_actions[s].filter_out);
2298
2299 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2300 s_actions++;
2301 send++;
2302 }
2303
2304 if (send)
2305 cluster_send_session(s);
2306 }
2307 }
2308
2309 LOG((t_actions || r_actions || s_actions) ? 3 : 4, 0, 0,
2310 "Regular cleanup: processed %d tunnels, %d radius and %d sessions\n",
2311 t_actions, r_actions, s_actions);
2312
2313 LOG(5, 0, 0, "End regular cleanup: checked %d tunnels, %d radius and %d sessions\n",
2314 t_slice, r_slice, s_slice);
2315 }
2316
2317 //
2318 // Are we in the middle of a tunnel update, or radius
2319 // requests??
2320 //
2321 static int still_busy(void)
2322 {
2323 int i;
2324 static time_t stopped_bgp = 0;
2325 static clockt last_talked = 0;
2326 static clockt start_busy_wait = 0;
2327
2328 if (!config->cluster_iam_master)
2329 {
2330 #ifdef BGP
2331 if (bgp_configured)
2332 {
2333 if (!stopped_bgp)
2334 {
2335 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2336
2337 for (i = 0; i < BGP_NUM_PEERS; i++)
2338 if (bgp_peers[i].state == Established)
2339 bgp_stop(&bgp_peers[i]);
2340
2341 stopped_bgp = time_now;
2342
2343 // we don't want to become master
2344 cluster_send_ping(0);
2345
2346 return 1;
2347 }
2348
2349 if (time_now < (stopped_bgp + QUIT_DELAY))
2350 return 1;
2351 }
2352 #endif /* BGP */
2353
2354 return 0;
2355 }
2356
2357 if (start_busy_wait == 0)
2358 start_busy_wait = TIME;
2359
2360 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2361 {
2362 if (!tunnel[i].controlc)
2363 continue;
2364
2365 if (last_talked != TIME)
2366 {
2367 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2368 last_talked = TIME;
2369 }
2370 return 1;
2371 }
2372
2373 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2374 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2375 {
2376 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2377 return 0;
2378 }
2379
2380 for (i = 1; i < MAXRADIUS; i++)
2381 {
2382 if (radius[i].state == RADIUSNULL)
2383 continue;
2384 if (radius[i].state == RADIUSWAIT)
2385 continue;
2386
2387 if (last_talked != TIME)
2388 {
2389 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2390 last_talked = TIME;
2391 }
2392 return 1;
2393 }
2394
2395 return 0;
2396 }
2397
2398 static fd_set readset;
2399 static int readset_n = 0;
2400
2401 // main loop - gets packets on tun or udp and processes them
2402 static void mainloop(void)
2403 {
2404 int i;
2405 uint8_t buf[65536];
2406 struct timeval to;
2407 clockt next_cluster_ping = 0; // send initial ping immediately
2408
2409 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2410 udpfd, tunfd, cluster_sockfd, controlfd);
2411
2412 FD_ZERO(&readset);
2413 FD_SET(udpfd, &readset);
2414 FD_SET(tunfd, &readset);
2415 FD_SET(controlfd, &readset);
2416 FD_SET(clifd, &readset);
2417 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2418 readset_n = udpfd;
2419 if (tunfd > readset_n) readset_n = tunfd;
2420 if (controlfd > readset_n) readset_n = controlfd;
2421 if (clifd > readset_n) readset_n = clifd;
2422 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2423
2424 while (!main_quit || still_busy())
2425 {
2426 fd_set r;
2427 int n = readset_n;
2428 #ifdef BGP
2429 fd_set w;
2430 int bgp_set[BGP_NUM_PEERS];
2431 #endif /* BGP */
2432 int more = 0;
2433
2434 if (config->reload_config)
2435 {
2436 // Update the config state based on config settings
2437 update_config();
2438 }
2439
2440 memcpy(&r, &readset, sizeof(fd_set));
2441 to.tv_sec = 0;
2442 to.tv_usec = 100000; // 1/10th of a second.
2443
2444 #ifdef BGP
2445 FD_ZERO(&w);
2446 for (i = 0; i < BGP_NUM_PEERS; i++)
2447 {
2448 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2449 if (bgp_set[i] & 1)
2450 {
2451 FD_SET(bgp_peers[i].sock, &r);
2452 if (bgp_peers[i].sock > n)
2453 n = bgp_peers[i].sock;
2454 }
2455
2456 if (bgp_set[i] & 2)
2457 {
2458 FD_SET(bgp_peers[i].sock, &w);
2459 if (bgp_peers[i].sock > n)
2460 n = bgp_peers[i].sock;
2461 }
2462 }
2463
2464 n = select(n + 1, &r, &w, 0, &to);
2465 #else /* BGP */
2466 n = select(n + 1, &r, 0, 0, &to);
2467 #endif /* BGP */
2468
2469 STAT(select_called);
2470
2471 TIME = now(NULL);
2472 if (n < 0)
2473 {
2474 if (errno == EINTR ||
2475 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2476 continue;
2477
2478 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2479 main_quit++;
2480 break;
2481 }
2482 else if (n)
2483 {
2484 struct sockaddr_in addr;
2485 int alen, c, s;
2486 int udp_pkts = 0;
2487 int tun_pkts = 0;
2488 int cluster_pkts = 0;
2489
2490 // nsctl commands
2491 if (FD_ISSET(controlfd, &r))
2492 {
2493 alen = sizeof(addr);
2494 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2495 n--;
2496 }
2497
2498 // RADIUS responses
2499 if (config->cluster_iam_master)
2500 {
2501 for (i = 0; i < config->num_radfds; i++)
2502 {
2503 if (FD_ISSET(radfds[i], &r))
2504 {
2505 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2506 n--;
2507 }
2508 }
2509 }
2510
2511 // CLI connections
2512 if (FD_ISSET(clifd, &r))
2513 {
2514 int cli;
2515
2516 alen = sizeof(addr);
2517 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
2518 {
2519 cli_do(cli);
2520 close(cli);
2521 }
2522 else
2523 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
2524
2525 n--;
2526 }
2527
2528 #ifdef BGP
2529 for (i = 0; i < BGP_NUM_PEERS; i++)
2530 {
2531 int isr = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0;
2532 int isw = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0;
2533 bgp_process(&bgp_peers[i], isr, isw);
2534 if (isr) n--;
2535 if (isw) n--;
2536 }
2537 #endif /* BGP */
2538
2539 for (c = 0; n && c < config->multi_read_count; c++)
2540 {
2541 // L2TP
2542 if (FD_ISSET(udpfd, &r))
2543 {
2544 alen = sizeof(addr);
2545 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2546 {
2547 processudp(buf, s, &addr);
2548 udp_pkts++;
2549 }
2550 else
2551 {
2552 FD_CLR(udpfd, &r);
2553 n--;
2554 }
2555 }
2556
2557 // incoming IP
2558 if (FD_ISSET(tunfd, &r))
2559 {
2560 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
2561 {
2562 processtun(buf, s);
2563 tun_pkts++;
2564 }
2565 else
2566 {
2567 FD_CLR(tunfd, &r);
2568 n--;
2569 }
2570 }
2571
2572 // cluster
2573 if (FD_ISSET(cluster_sockfd, &r))
2574 {
2575 alen = sizeof(addr);
2576 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
2577 {
2578 processcluster(buf, s, addr.sin_addr.s_addr);
2579 cluster_pkts++;
2580 }
2581 else
2582 {
2583 FD_CLR(cluster_sockfd, &r);
2584 n--;
2585 }
2586 }
2587 }
2588
2589 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
2590 STAT(multi_read_used);
2591
2592 if (c >= config->multi_read_count)
2593 {
2594 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
2595 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
2596
2597 STAT(multi_read_exceeded);
2598 more++;
2599 }
2600 }
2601
2602 // Runs on every machine (master and slaves).
2603 if (cluster_sockfd && next_cluster_ping <= TIME)
2604 {
2605 // Check to see which of the cluster is still alive..
2606
2607 cluster_send_ping(basetime); // Only does anything if we're a slave
2608 cluster_check_master(); // ditto.
2609
2610 cluster_heartbeat(); // Only does anything if we're a master.
2611 cluster_check_slaves(); // ditto.
2612
2613 master_update_counts(); // If we're a slave, send our byte counters to our master.
2614
2615 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2616 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2617 else
2618 next_cluster_ping = TIME + config->cluster_hb_interval;
2619 }
2620
2621 if (!config->cluster_iam_master)
2622 continue;
2623
2624 // Run token bucket filtering queue..
2625 // Only run it every 1/10th of a second.
2626 {
2627 static clockt last_run = 0;
2628 if (last_run != TIME)
2629 {
2630 last_run = TIME;
2631 tbf_run_timer();
2632 }
2633 }
2634
2635 // Handle timeouts, retries etc.
2636 {
2637 static double last_clean = 0;
2638 double this_clean;
2639 double diff;
2640
2641 TIME = now(&this_clean);
2642 diff = this_clean - last_clean;
2643
2644 // Run during idle time (after we've handled
2645 // all incoming packets) or every 1/10th sec
2646 if (!more || diff > 0.1)
2647 {
2648 regular_cleanups(diff);
2649 last_clean = this_clean;
2650 }
2651 }
2652
2653 if (*config->accounting_dir)
2654 {
2655 static clockt next_acct = 0;
2656 static clockt next_shut_acct = 0;
2657
2658 if (next_acct <= TIME)
2659 {
2660 // Dump accounting data
2661 next_acct = TIME + ACCT_TIME;
2662 next_shut_acct = TIME + ACCT_SHUT_TIME;
2663 dump_acct_info(1);
2664 }
2665 else if (next_shut_acct <= TIME)
2666 {
2667 // Dump accounting data for shutdown sessions
2668 next_shut_acct = TIME + ACCT_SHUT_TIME;
2669 if (shut_acct_n)
2670 dump_acct_info(0);
2671 }
2672 }
2673 }
2674
2675 // Are we the master and shutting down??
2676 if (config->cluster_iam_master)
2677 cluster_heartbeat(); // Flush any queued changes..
2678
2679 // Ok. Notify everyone we're shutting down. If we're
2680 // the master, this will force an election.
2681 cluster_send_ping(0);
2682
2683 //
2684 // Important!!! We MUST not process any packets past this point!
2685 LOG(1, 0, 0, "Clean shutdown complete\n");
2686 }
2687
2688 static void stripdomain(char *host)
2689 {
2690 char *p;
2691
2692 if ((p = strchr(host, '.')))
2693 {
2694 char *domain = 0;
2695 char _domain[1024];
2696
2697 // strip off domain
2698 FILE *resolv = fopen("/etc/resolv.conf", "r");
2699 if (resolv)
2700 {
2701 char buf[1024];
2702 char *b;
2703
2704 while (fgets(buf, sizeof(buf), resolv))
2705 {
2706 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
2707 continue;
2708
2709 if (!isspace(buf[6]))
2710 continue;
2711
2712 b = buf + 7;
2713 while (isspace(*b)) b++;
2714
2715 if (*b)
2716 {
2717 char *d = b;
2718 while (*b && !isspace(*b)) b++;
2719 *b = 0;
2720 if (buf[0] == 'd') // domain is canonical
2721 {
2722 domain = d;
2723 break;
2724 }
2725
2726 // first search line
2727 if (!domain)
2728 {
2729 // hold, may be subsequent domain line
2730 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
2731 domain = _domain;
2732 }
2733 }
2734 }
2735
2736 fclose(resolv);
2737 }
2738
2739 if (domain)
2740 {
2741 int hl = strlen(host);
2742 int dl = strlen(domain);
2743 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
2744 host[hl -dl - 1] = 0;
2745 }
2746 else
2747 {
2748 *p = 0; // everything after first dot
2749 }
2750 }
2751 }
2752
2753 // Init data structures
2754 static void initdata(int optdebug, char *optconfig)
2755 {
2756 int i;
2757
2758 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
2759 {
2760 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
2761 exit(1);
2762 }
2763 if (!(config = shared_malloc(sizeof(configt))))
2764 {
2765 LOG(0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
2766 exit(1);
2767 }
2768 memset(config, 0, sizeof(configt));
2769 time(&config->start_time);
2770 strncpy(config->config_file, optconfig, strlen(optconfig));
2771 config->debug = optdebug;
2772 config->num_tbfs = MAXTBFS;
2773 config->rl_rate = 28; // 28kbps
2774 config->cluster_master_min_adv = 1;
2775
2776 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
2777 {
2778 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
2779 exit(1);
2780 }
2781 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
2782 {
2783 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
2784 exit(1);
2785 }
2786
2787 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
2788 {
2789 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
2790 exit(1);
2791 }
2792
2793 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
2794 {
2795 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
2796 exit(1);
2797 }
2798
2799 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
2800 {
2801 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
2802 exit(1);
2803 }
2804
2805 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
2806 {
2807 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
2808 exit(1);
2809 }
2810 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
2811
2812 #ifdef RINGBUFFER
2813 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
2814 {
2815 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
2816 exit(1);
2817 }
2818 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2819 #endif
2820
2821 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
2822 {
2823 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
2824 exit(1);
2825 }
2826 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2827
2828 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
2829 {
2830 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
2831 exit(1);
2832 }
2833 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2834
2835 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2836 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2837 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2838 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2839
2840 // Put all the sessions on the free list marked as undefined.
2841 for (i = 1; i < MAXSESSION; i++)
2842 {
2843 session[i].next = i + 1;
2844 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2845 }
2846 session[MAXSESSION - 1].next = 0;
2847 sessionfree = 1;
2848
2849 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2850 for (i = 1; i < MAXTUNNEL; i++)
2851 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2852
2853 if (!*hostname)
2854 {
2855 // Grab my hostname unless it's been specified
2856 gethostname(hostname, sizeof(hostname));
2857 stripdomain(hostname);
2858 }
2859
2860 _statistics->start_time = _statistics->last_reset = time(NULL);
2861
2862 #ifdef BGP
2863 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
2864 {
2865 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
2866 exit(1);
2867 }
2868 #endif /* BGP */
2869 }
2870
2871 static int assign_ip_address(sessionidt s)
2872 {
2873 uint32_t i;
2874 int best = -1;
2875 time_t best_time = time_now;
2876 char *u = session[s].user;
2877 char reuse = 0;
2878
2879
2880 CSTAT(call_assign_ip_address);
2881
2882 for (i = 1; i < ip_pool_size; i++)
2883 {
2884 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2885 continue;
2886
2887 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2888 {
2889 best = i;
2890 reuse = 1;
2891 break;
2892 }
2893
2894 if (ip_address_pool[i].last < best_time)
2895 {
2896 best = i;
2897 if (!(best_time = ip_address_pool[i].last))
2898 break; // never used, grab this one
2899 }
2900 }
2901
2902 if (best < 0)
2903 {
2904 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2905 return 0;
2906 }
2907
2908 session[s].ip = ip_address_pool[best].address;
2909 session[s].ip_pool_index = best;
2910 ip_address_pool[best].assigned = 1;
2911 ip_address_pool[best].last = time_now;
2912 ip_address_pool[best].session = s;
2913 if (session[s].walled_garden)
2914 /* Don't track addresses of users in walled garden (note: this
2915 means that their address isn't "sticky" even if they get
2916 un-gardened). */
2917 ip_address_pool[best].user[0] = 0;
2918 else
2919 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2920
2921 STAT(ip_allocated);
2922 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
2923 reuse ? "Reusing" : "Allocating", best);
2924
2925 return 1;
2926 }
2927
2928 static void free_ip_address(sessionidt s)
2929 {
2930 int i = session[s].ip_pool_index;
2931
2932
2933 CSTAT(call_free_ip_address);
2934
2935 if (!session[s].ip)
2936 return; // what the?
2937
2938 if (i < 0) // Is this actually part of the ip pool?
2939 i = 0;
2940
2941 STAT(ip_freed);
2942 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2943 session[s].ip = 0;
2944 ip_address_pool[i].assigned = 0;
2945 ip_address_pool[i].session = 0;
2946 ip_address_pool[i].last = time_now;
2947 }
2948
2949 //
2950 // Fsck the address pool against the session table.
2951 // Normally only called when we become a master.
2952 //
2953 // This isn't perfect: We aren't keep tracking of which
2954 // users used to have an IP address.
2955 //
2956 void rebuild_address_pool(void)
2957 {
2958 int i;
2959
2960 //
2961 // Zero the IP pool allocation, and build
2962 // a map from IP address to pool index.
2963 for (i = 1; i < MAXIPPOOL; ++i)
2964 {
2965 ip_address_pool[i].assigned = 0;
2966 ip_address_pool[i].session = 0;
2967 if (!ip_address_pool[i].address)
2968 continue;
2969
2970 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2971 }
2972
2973 for (i = 0; i < MAXSESSION; ++i)
2974 {
2975 int ipid;
2976 if (!(session[i].opened && session[i].ip))
2977 continue;
2978 ipid = - lookup_ipmap(htonl(session[i].ip));
2979
2980 if (session[i].ip_pool_index < 0)
2981 {
2982 // Not allocated out of the pool.
2983 if (ipid < 1) // Not found in the pool either? good.
2984 continue;
2985
2986 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2987 i, fmtaddr(session[i].ip, 0), ipid);
2988
2989 // Fall through and process it as part of the pool.
2990 }
2991
2992
2993 if (ipid > MAXIPPOOL || ipid < 0)
2994 {
2995 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2996 ipid = -1;
2997 session[i].ip_pool_index = ipid;
2998 continue;
2999 }
3000
3001 ip_address_pool[ipid].assigned = 1;
3002 ip_address_pool[ipid].session = i;
3003 ip_address_pool[ipid].last = time_now;
3004 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3005 session[i].ip_pool_index = ipid;
3006 cache_ipmap(session[i].ip, i); // Fix the ip map.
3007 }
3008 }
3009
3010 //
3011 // Fix the address pool to match a changed session.
3012 // (usually when the master sends us an update).
3013 static void fix_address_pool(int sid)
3014 {
3015 int ipid;
3016
3017 ipid = session[sid].ip_pool_index;
3018
3019 if (ipid > ip_pool_size)
3020 return; // Ignore it. rebuild_address_pool will fix it up.
3021
3022 if (ip_address_pool[ipid].address != session[sid].ip)
3023 return; // Just ignore it. rebuild_address_pool will take care of it.
3024
3025 ip_address_pool[ipid].assigned = 1;
3026 ip_address_pool[ipid].session = sid;
3027 ip_address_pool[ipid].last = time_now;
3028 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3029 }
3030
3031 //
3032 // Add a block of addresses to the IP pool to hand out.
3033 //
3034 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3035 {
3036 int i;
3037 if (mask == 0)
3038 mask = 0xffffffff; // Host route only.
3039
3040 addr &= mask;
3041
3042 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3043 return ;
3044
3045 for (i = addr ;(i & mask) == addr; ++i)
3046 {
3047 if ((i & 0xff) == 0 || (i&0xff) == 255)
3048 continue; // Skip 0 and broadcast addresses.
3049
3050 ip_address_pool[ip_pool_size].address = i;
3051 ip_address_pool[ip_pool_size].assigned = 0;
3052 ++ip_pool_size;
3053 if (ip_pool_size >= MAXIPPOOL)
3054 {
3055 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3056 return;
3057 }
3058 }
3059 }
3060
3061 // Initialize the IP address pool
3062 static void initippool()
3063 {
3064 FILE *f;
3065 char *p;
3066 char buf[4096];
3067 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3068
3069 if (!(f = fopen(IPPOOLFILE, "r")))
3070 {
3071 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3072 exit(1);
3073 }
3074
3075 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3076 {
3077 char *pool = buf;
3078 buf[4095] = 0; // Force it to be zero terminated/
3079
3080 if (*buf == '#' || *buf == '\n')
3081 continue; // Skip comments / blank lines
3082 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3083 if ((p = (char *)strchr(buf, ':')))
3084 {
3085 in_addr_t src;
3086 *p = '\0';
3087 src = inet_addr(buf);
3088 if (src == INADDR_NONE)
3089 {
3090 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3091 exit(1);
3092 }
3093 // This entry is for a specific IP only
3094 if (src != config->bind_address)
3095 continue;
3096 *p = ':';
3097 pool = p+1;
3098 }
3099 if ((p = (char *)strchr(pool, '/')))
3100 {
3101 // It's a range
3102 int numbits = 0;
3103 in_addr_t start = 0, mask = 0;
3104
3105 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3106 *p++ = 0;
3107 if (!*p || !(numbits = atoi(p)))
3108 {
3109 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3110 continue;
3111 }
3112 start = ntohl(inet_addr(pool));
3113 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3114
3115 // Add a static route for this pool
3116 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3117 fmtaddr(htonl(start), 0), 32 + mask);
3118
3119 routeset(0, start, mask, 0, 1);
3120
3121 add_to_ip_pool(start, mask);
3122 }
3123 else
3124 {
3125 // It's a single ip address
3126 add_to_ip_pool(inet_addr(pool), 0);
3127 }
3128 }
3129 fclose(f);
3130 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3131 }
3132
3133 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3134 {
3135 struct sockaddr_in snoop_addr = {0};
3136 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3137 return;
3138
3139 snoop_addr.sin_family = AF_INET;
3140 snoop_addr.sin_addr.s_addr = destination;
3141 snoop_addr.sin_port = ntohs(port);
3142
3143 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3144 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3145 htons(snoop_addr.sin_port));
3146
3147 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3148 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3149
3150 STAT(packets_snooped);
3151 }
3152
3153 static int dump_session(FILE **f, sessiont *s)
3154 {
3155 if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
3156 return 1;
3157
3158 if (!*f)
3159 {
3160 char filename[1024];
3161 char timestr[64];
3162 time_t now = time(NULL);
3163
3164 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3165 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3166
3167 if (!(*f = fopen(filename, "w")))
3168 {
3169 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3170 return 0;
3171 }
3172
3173 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3174 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3175 "# host: %s\n"
3176 "# time: %ld\n"
3177 "# uptime: %ld\n"
3178 "# format: username ip qos uptxoctets downrxoctets\n",
3179 hostname,
3180 now,
3181 now - basetime);
3182 }
3183
3184 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3185 fprintf(*f, "%s %s %d %u %u\n",
3186 s->user, // username
3187 fmtaddr(htonl(s->ip), 0), // ip
3188 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3189 (uint32_t) s->cin, // uptxoctets
3190 (uint32_t) s->cout); // downrxoctets
3191
3192 s->pin = s->cin = 0;
3193 s->pout = s->cout = 0;
3194
3195 return 1;
3196 }
3197
3198 static void dump_acct_info(int all)
3199 {
3200 int i;
3201 FILE *f = NULL;
3202
3203
3204 CSTAT(call_dump_acct_info);
3205
3206 if (shut_acct_n)
3207 {
3208 for (i = 0; i < shut_acct_n; i++)
3209 dump_session(&f, &shut_acct[i]);
3210
3211 shut_acct_n = 0;
3212 }
3213
3214 if (all)
3215 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3216 dump_session(&f, &session[i]);
3217
3218 if (f)
3219 fclose(f);
3220 }
3221
3222 // Main program
3223 int main(int argc, char *argv[])
3224 {
3225 int i;
3226 int optdebug = 0;
3227 char *optconfig = CONFIGFILE;
3228
3229 time(&basetime); // start clock
3230
3231 // scan args
3232 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3233 {
3234 switch (i)
3235 {
3236 case 'd':
3237 if (fork()) exit(0);
3238 setsid();
3239 freopen("/dev/null", "r", stdin);
3240 freopen("/dev/null", "w", stdout);
3241 freopen("/dev/null", "w", stderr);
3242 break;
3243 case 'v':
3244 optdebug++;
3245 break;
3246 case 'c':
3247 optconfig = optarg;
3248 break;
3249 case 'h':
3250 snprintf(hostname, sizeof(hostname), "%s", optarg);
3251 break;
3252 default:
3253 printf("Args are:\n"
3254 "\t-d\t\tDetach from terminal\n"
3255 "\t-c <file>\tConfig file\n"
3256 "\t-h <hostname>\tForce hostname\n"
3257 "\t-v\t\tDebug\n");
3258
3259 return (0);
3260 break;
3261 }
3262 }
3263
3264 // Start the timer routine off
3265 time(&time_now);
3266 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3267 signal(SIGALRM, sigalrm_handler);
3268 siginterrupt(SIGALRM, 0);
3269
3270 initplugins();
3271 initdata(optdebug, optconfig);
3272
3273 init_cli(hostname);
3274 read_config_file();
3275 init_tbf(config->num_tbfs);
3276
3277 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3278 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3279 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3280 {
3281 struct rlimit rlim;
3282 rlim.rlim_cur = RLIM_INFINITY;
3283 rlim.rlim_max = RLIM_INFINITY;
3284 // Remove the maximum core size
3285 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3286 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3287
3288 // Make core dumps go to /tmp
3289 chdir("/tmp");
3290 }
3291
3292 if (config->scheduler_fifo)
3293 {
3294 int ret;
3295 struct sched_param params = {0};
3296 params.sched_priority = 1;
3297
3298 if (get_nprocs() < 2)
3299 {
3300 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3301 config->scheduler_fifo = 0;
3302 }
3303 else
3304 {
3305 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3306 {
3307 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3308 }
3309 else
3310 {
3311 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3312 config->scheduler_fifo = 0;
3313 }
3314 }
3315 }
3316
3317 /* Set up the cluster communications port. */
3318 if (cluster_init() < 0)
3319 exit(1);
3320
3321 #ifdef BGP
3322 signal(SIGPIPE, SIG_IGN);
3323 bgp_setup(config->as_number);
3324 bgp_add_route(config->bind_address, 0xffffffff);
3325 for (i = 0; i < BGP_NUM_PEERS; i++)
3326 {
3327 if (config->neighbour[i].name[0])
3328 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3329 config->neighbour[i].as, config->neighbour[i].keepalive,
3330 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3331 }
3332 #endif /* BGP */
3333
3334 inittun();
3335 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3336
3337 initudp();
3338 initrad();
3339 initippool();
3340
3341 read_state();
3342
3343 signal(SIGHUP, sighup_handler);
3344 signal(SIGTERM, sigterm_handler);
3345 signal(SIGINT, sigterm_handler);
3346 signal(SIGQUIT, sigquit_handler);
3347 signal(SIGCHLD, sigchild_handler);
3348
3349 // Prevent us from getting paged out
3350 if (config->lock_pages)
3351 {
3352 if (!mlockall(MCL_CURRENT))
3353 LOG(1, 0, 0, "Locking pages into memory\n");
3354 else
3355 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3356 }
3357
3358 alarm(1);
3359
3360 // Drop privileges here
3361 if (config->target_uid > 0 && geteuid() == 0)
3362 setuid(config->target_uid);
3363
3364 mainloop();
3365
3366 /* remove plugins (so cleanup code gets run) */
3367 plugins_done();
3368
3369 // Remove the PID file if we wrote it
3370 if (config->wrote_pid && *config->pid_file == '/')
3371 unlink(config->pid_file);
3372
3373 /* kill CLI children */
3374 signal(SIGTERM, SIG_IGN);
3375 kill(0, SIGTERM);
3376 return 0;
3377 }
3378
3379 static void sighup_handler(int sig)
3380 {
3381 if (log_stream && log_stream != stderr)
3382 {
3383 fclose(log_stream);
3384 log_stream = NULL;
3385 }
3386
3387 read_config_file();
3388 }
3389
3390 static void sigalrm_handler(int sig)
3391 {
3392 // Log current traffic stats
3393
3394 snprintf(config->bandwidth, sizeof(config->bandwidth),
3395 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3396 (udp_rx / 1024.0 / 1024.0 * 8),
3397 (eth_tx / 1024.0 / 1024.0 * 8),
3398 (eth_rx / 1024.0 / 1024.0 * 8),
3399 (udp_tx / 1024.0 / 1024.0 * 8),
3400 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3401 udp_rx_pkt, eth_rx_pkt);
3402
3403 udp_tx = udp_rx = 0;
3404 udp_rx_pkt = eth_rx_pkt = 0;
3405 eth_tx = eth_rx = 0;
3406
3407 if (config->dump_speed)
3408 printf("%s\n", config->bandwidth);
3409
3410 // Update the internal time counter
3411 time(&time_now);
3412 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3413 alarm(1);
3414
3415 {
3416 // Run timer hooks
3417 struct param_timer p = { time_now };
3418 run_plugins(PLUGIN_TIMER, &p);
3419 }
3420
3421 }
3422
3423 static void sigterm_handler(int sig)
3424 {
3425 LOG(1, 0, 0, "Shutting down cleanly\n");
3426 if (config->save_state)
3427 dump_state();
3428
3429 main_quit++;
3430 }
3431
3432 static void sigquit_handler(int sig)
3433 {
3434 int i;
3435
3436 LOG(1, 0, 0, "Shutting down without saving sessions\n");
3437
3438 if (config->cluster_iam_master)
3439 {
3440 for (i = 1; i < MAXSESSION; i++)
3441 {
3442 if (session[i].opened)
3443 sessionkill(i, "L2TPNS Closing");
3444 }
3445 for (i = 1; i < MAXTUNNEL; i++)
3446 {
3447 if (tunnel[i].ip || tunnel[i].state)
3448 tunnelshutdown(i, "L2TPNS Closing");
3449 }
3450 }
3451
3452 main_quit++;
3453 }
3454
3455 static void sigchild_handler(int sig)
3456 {
3457 while (waitpid(-1, NULL, WNOHANG) > 0)
3458 ;
3459 }
3460
3461 static void read_state()
3462 {
3463 struct stat sb;
3464 int i;
3465 ippoolt itmp;
3466 FILE *f;
3467 char magic[sizeof(DUMP_MAGIC) - 1];
3468 uint32_t buf[2];
3469
3470 if (!config->save_state)
3471 {
3472 unlink(STATEFILE);
3473 return ;
3474 }
3475
3476 if (stat(STATEFILE, &sb) < 0)
3477 {
3478 unlink(STATEFILE);
3479 return ;
3480 }
3481
3482 if (sb.st_mtime < (time(NULL) - 60))
3483 {
3484 LOG(0, 0, 0, "State file is too old to read, ignoring\n");
3485 unlink(STATEFILE);
3486 return ;
3487 }
3488
3489 f = fopen(STATEFILE, "r");
3490 unlink(STATEFILE);
3491
3492 if (!f)
3493 {
3494 LOG(0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3495 exit(1);
3496 }
3497
3498 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3499 {
3500 LOG(0, 0, 0, "Bad state file magic\n");
3501 exit(1);
3502 }
3503
3504 LOG(1, 0, 0, "Reading state information\n");
3505 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3506 {
3507 LOG(0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3508 exit(1);
3509 }
3510
3511 if (buf[0] > ip_pool_size)
3512 {
3513 LOG(0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3514 exit(1);
3515 }
3516
3517 LOG(2, 0, 0, "Loading %u ip addresses\n", buf[0]);
3518 for (i = 0; i < buf[0]; i++)
3519 {
3520 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3521 {
3522 LOG(0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3523 exit(1);
3524 }
3525
3526 if (itmp.address != ip_address_pool[i].address)
3527 {
3528 LOG(0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3529 exit(1);
3530 }
3531
3532 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3533 }
3534
3535 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3536 {
3537 LOG(0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3538 exit(1);
3539 }
3540
3541 LOG(2, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3542 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3543 {
3544 LOG(0, 0, 0, "Error reading tunnel data from state file\n");
3545 exit(1);
3546 }
3547
3548 for (i = 0; i < MAXTUNNEL; i++)
3549 {
3550 tunnel[i].controlc = 0;
3551 tunnel[i].controls = NULL;
3552 tunnel[i].controle = NULL;
3553 if (*tunnel[i].hostname)
3554 LOG(3, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3555 }
3556
3557 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3558 {
3559 LOG(0, 0, 0, "Error/mismatch reading session header from state file\n");
3560 exit(1);
3561 }
3562
3563 LOG(2, 0, 0, "Loading %u sessions\n", MAXSESSION);
3564 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3565 {
3566 LOG(0, 0, 0, "Error reading session data from state file\n");
3567 exit(1);
3568 }
3569
3570 for (i = 0; i < MAXSESSION; i++)
3571 {
3572 session[i].tbf_in = 0;
3573 session[i].tbf_out = 0;
3574 if (session[i].opened)
3575 {
3576 LOG(2, i, 0, "Loaded active session for user %s\n", session[i].user);
3577 if (session[i].ip)
3578 sessionsetup(session[i].tunnel, i);
3579 }
3580 }
3581
3582 fclose(f);
3583 LOG(0, 0, 0, "Loaded saved state information\n");
3584 }
3585
3586 static void dump_state()
3587 {
3588 FILE *f;
3589 uint32_t buf[2];
3590
3591 if (!config->save_state)
3592 return;
3593
3594 do
3595 {
3596 if (!(f = fopen(STATEFILE, "w")))
3597 break;
3598
3599 LOG(1, 0, 0, "Dumping state information\n");
3600
3601 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
3602 break;
3603
3604 LOG(2, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3605 buf[0] = ip_pool_size;
3606 buf[1] = sizeof(ippoolt);
3607 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3608 break;
3609 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
3610 break;
3611
3612 LOG(2, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3613 buf[0] = MAXTUNNEL;
3614 buf[1] = sizeof(tunnelt);
3615 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3616 break;
3617 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3618 break;
3619
3620 LOG(2, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3621 buf[0] = MAXSESSION;
3622 buf[1] = sizeof(sessiont);
3623 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3624 break;
3625 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3626 break;
3627
3628 if (fclose(f) == 0)
3629 return ; // OK
3630 }
3631 while (0);
3632
3633 LOG(0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3634 unlink(STATEFILE);
3635 }
3636
3637 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
3638 {
3639 MD5_CTX ctx;
3640 *challenge_response = NULL;
3641
3642 if (!*config->l2tpsecret)
3643 {
3644 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3645 return;
3646 }
3647
3648 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
3649
3650 *challenge_response = (char *)calloc(17, 1);
3651
3652 MD5Init(&ctx);
3653 MD5Update(&ctx, &id, 1);
3654 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3655 MD5Update(&ctx, challenge, challenge_length);
3656 MD5Final(*challenge_response, &ctx);
3657
3658 return;
3659 }
3660
3661 static int facility_value(char *name)
3662 {
3663 int i;
3664 for (i = 0; facilitynames[i].c_name; i++)
3665 {
3666 if (strcmp(facilitynames[i].c_name, name) == 0)
3667 return facilitynames[i].c_val;
3668 }
3669 return 0;
3670 }
3671
3672 static void update_config()
3673 {
3674 int i;
3675 static int timeout = 0;
3676 static int interval = 0;
3677
3678 // Update logging
3679 closelog();
3680 syslog_log = 0;
3681 if (log_stream)
3682 {
3683 fclose(log_stream);
3684 log_stream = NULL;
3685 }
3686 if (*config->log_filename)
3687 {
3688 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3689 {
3690 char *p = config->log_filename + 7;
3691 if (*p)
3692 {
3693 openlog("l2tpns", LOG_PID, facility_value(p));
3694 syslog_log = 1;
3695 }
3696 }
3697 else if (strchr(config->log_filename, '/') == config->log_filename)
3698 {
3699 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3700 {
3701 fseek(log_stream, 0, SEEK_END);
3702 setbuf(log_stream, NULL);
3703 }
3704 else
3705 {
3706 log_stream = stderr;
3707 setbuf(log_stream, NULL);
3708 }
3709 }
3710 }
3711 else
3712 {
3713 log_stream = stderr;
3714 setbuf(log_stream, NULL);
3715 }
3716
3717
3718 // Update radius
3719 config->numradiusservers = 0;
3720 for (i = 0; i < MAXRADSERVER; i++)
3721 if (config->radiusserver[i])
3722 {
3723 config->numradiusservers++;
3724 // Set radius port: if not set, take the port from the
3725 // first radius server. For the first radius server,
3726 // take the #defined default value from l2tpns.h
3727
3728 // test twice, In case someone works with
3729 // a secondary radius server without defining
3730 // a primary one, this will work even then.
3731 if (i>0 && !config->radiusport[i])
3732 config->radiusport[i] = config->radiusport[i-1];
3733 if (!config->radiusport[i])
3734 config->radiusport[i] = RADPORT;
3735 }
3736
3737 if (!config->numradiusservers)
3738 LOG(0, 0, 0, "No RADIUS servers defined!\n");
3739
3740 config->num_radfds = 1 << RADIUS_SHIFT;
3741
3742 // Update plugins
3743 for (i = 0; i < MAXPLUGINS; i++)
3744 {
3745 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3746 continue;
3747
3748 if (*config->plugins[i])
3749 {
3750 // Plugin added
3751 add_plugin(config->plugins[i]);
3752 }
3753 else if (*config->old_plugins[i])
3754 {
3755 // Plugin removed
3756 remove_plugin(config->old_plugins[i]);
3757 }
3758 }
3759 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3760 if (!config->multi_read_count) config->multi_read_count = 10;
3761 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3762 if (!*config->cluster_interface)
3763 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3764
3765 if (!config->cluster_hb_interval)
3766 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3767
3768 if (!config->cluster_hb_timeout)
3769 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3770
3771 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3772 {
3773 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3774 // late, ensure we're sufficiently larger than that
3775 int t = 4 * config->cluster_hb_interval + 11;
3776
3777 if (config->cluster_hb_timeout < t)
3778 {
3779 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3780 config->cluster_hb_timeout = t;
3781 }
3782
3783 // Push timing changes to the slaves immediately if we're the master
3784 if (config->cluster_iam_master)
3785 cluster_heartbeat();
3786
3787 interval = config->cluster_hb_interval;
3788 timeout = config->cluster_hb_timeout;
3789 }
3790
3791 // Write PID file
3792 if (*config->pid_file == '/' && !config->wrote_pid)
3793 {
3794 FILE *f;
3795 if ((f = fopen(config->pid_file, "w")))
3796 {
3797 fprintf(f, "%d\n", getpid());
3798 fclose(f);
3799 config->wrote_pid = 1;
3800 }
3801 else
3802 {
3803 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3804 }
3805 }
3806
3807 config->reload_config = 0;
3808 }
3809
3810 static void read_config_file()
3811 {
3812 FILE *f;
3813
3814 if (!config->config_file) return;
3815 if (!(f = fopen(config->config_file, "r")))
3816 {
3817 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3818 return;
3819 }
3820
3821 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
3822 cli_do_file(f);
3823 LOG(3, 0, 0, "Done reading config file\n");
3824 fclose(f);
3825 update_config();
3826 }
3827
3828 int sessionsetup(tunnelidt t, sessionidt s)
3829 {
3830 // A session now exists, set it up
3831 in_addr_t ip;
3832 char *user;
3833 sessionidt i;
3834 int r;
3835
3836 CSTAT(call_sessionsetup);
3837
3838 LOG(3, s, t, "Doing session setup for session\n");
3839
3840 if (!session[s].ip)
3841 {
3842 assign_ip_address(s);
3843 if (!session[s].ip)
3844 {
3845 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3846 sessionshutdown(s, "No IP addresses available");
3847 return 0;
3848 }
3849 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
3850 fmtaddr(htonl(session[s].ip), 0));
3851 }
3852
3853
3854 // Make sure this is right
3855 session[s].tunnel = t;
3856
3857 // zap old sessions with same IP and/or username
3858 // Don't kill gardened sessions - doing so leads to a DoS
3859 // from someone who doesn't need to know the password
3860 {
3861 ip = session[s].ip;
3862 user = session[s].user;
3863 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3864 {
3865 if (i == s) continue;
3866 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3867 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3868 sessionkill(i, "Duplicate session for users");
3869 }
3870 }
3871
3872 {
3873 int routed = 0;
3874
3875 // Add the route for this session.
3876 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3877 {
3878 if ((session[s].ip & session[s].route[r].mask) ==
3879 (session[s].route[r].ip & session[s].route[r].mask))
3880 routed++;
3881
3882 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
3883 }
3884
3885 // Static IPs need to be routed if not already
3886 // convered by a Framed-Route. Anything else is part
3887 // of the IP address pool and is already routed, it
3888 // just needs to be added to the IP cache.
3889 if (session[s].ip_pool_index == -1) // static ip
3890 {
3891 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
3892 }
3893 else
3894 cache_ipmap(session[s].ip, s);
3895 }
3896
3897 if (!session[s].unique_id)
3898 {
3899 // did this session just finish radius?
3900 LOG(3, s, t, "Sending initial IPCP to client\n");
3901 sendipcp(t, s);
3902 session[s].unique_id = ++last_id;
3903 }
3904
3905 // Run the plugin's against this new session.
3906 {
3907 struct param_new_session data = { &tunnel[t], &session[s] };
3908 run_plugins(PLUGIN_NEW_SESSION, &data);
3909 }
3910
3911 // Allocate TBFs if throttled
3912 if (session[s].throttle_in || session[s].throttle_out)
3913 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
3914
3915 session[s].last_packet = time_now;
3916
3917 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
3918 fmtaddr(htonl(session[s].ip), 0),
3919 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
3920
3921 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3922
3923 return 1; // RADIUS OK and IP allocated, done...
3924 }
3925
3926 //
3927 // This session just got dropped on us by the master or something.
3928 // Make sure our tables up up to date...
3929 //
3930 int load_session(sessionidt s, sessiont *new)
3931 {
3932 int i;
3933 int newip = 0;
3934
3935 // Sanity checks.
3936 if (new->ip_pool_index >= MAXIPPOOL ||
3937 new->tunnel >= MAXTUNNEL)
3938 {
3939 LOG(0, s, 0, "Strange session update received!\n");
3940 // FIXME! What to do here?
3941 return 0;
3942 }
3943
3944 //
3945 // Ok. All sanity checks passed. Now we're committed to
3946 // loading the new session.
3947 //
3948
3949 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3950
3951 // See if routes/ip cache need updating
3952 if (new->ip != session[s].ip)
3953 newip++;
3954
3955 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3956 if (new->route[i].ip != session[s].route[i].ip ||
3957 new->route[i].mask != session[s].route[i].mask)
3958 newip++;
3959
3960 // needs update
3961 if (newip)
3962 {
3963 int routed = 0;
3964
3965 // remove old routes...
3966 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3967 {
3968 if ((session[s].ip & session[s].route[i].mask) ==
3969 (session[s].route[i].ip & session[s].route[i].mask))
3970 routed++;
3971
3972 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
3973 }
3974
3975 // ...ip
3976 if (session[s].ip)
3977 {
3978 if (session[s].ip_pool_index == -1) // static IP
3979 {
3980 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
3981 }
3982 else // It's part of the IP pool, remove it manually.
3983 uncache_ipmap(session[s].ip);
3984 }
3985
3986 routed = 0;
3987
3988 // add new routes...
3989 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
3990 {
3991 if ((new->ip & new->route[i].mask) ==
3992 (new->route[i].ip & new->route[i].mask))
3993 routed++;
3994
3995 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
3996 }
3997
3998 // ...ip
3999 if (new->ip)
4000 {
4001 // If there's a new one, add it.
4002 if (new->ip_pool_index == -1)
4003 {
4004 if (!routed) routeset(s, new->ip, 0, 0, 1);
4005 }
4006 else
4007 cache_ipmap(new->ip, s);
4008 }
4009 }
4010
4011 // check filters
4012 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4013 {
4014 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4015 new->filter_in = 0;
4016 }
4017
4018 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4019 {
4020 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4021 new->filter_out = 0;
4022 }
4023
4024 if (new->filter_in != session[s].filter_in)
4025 {
4026 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4027 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4028 }
4029
4030 if (new->filter_out != session[s].filter_out)
4031 {
4032 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4033 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4034 }
4035
4036 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4037 // for walking the sessions to forward byte counts to the master.
4038 config->cluster_highest_sessionid = s;
4039
4040 // TEMP: old session struct used a uint32_t to define the throttle
4041 // speed for both up/down, new uses a uint16_t for each. Deal with
4042 // sessions from an old master for migration.
4043 if (new->throttle_out == 0 && new->tbf_out)
4044 new->throttle_out = new->throttle_in;
4045
4046 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4047
4048 // Do fixups into address pool.
4049 if (new->ip_pool_index != -1)
4050 fix_address_pool(s);
4051
4052 return 1;
4053 }
4054
4055 static void initplugins()
4056 {
4057 int i;
4058
4059 loaded_plugins = ll_init();
4060 // Initialize the plugins to nothing
4061 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4062 plugins[i] = ll_init();
4063 }
4064
4065 static void *open_plugin(char *plugin_name, int load)
4066 {
4067 char path[256] = "";
4068
4069 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4070 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4071 return dlopen(path, RTLD_NOW);
4072 }
4073
4074 // plugin callback to get a config value
4075 static void *getconfig(char *key, enum config_typet type)
4076 {
4077 int i;
4078
4079 for (i = 0; config_values[i].key; i++)
4080 {
4081 if (!strcmp(config_values[i].key, key))
4082 {
4083 if (config_values[i].type == type)
4084 return ((void *) config) + config_values[i].offset;
4085
4086 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4087 key, type, config_values[i].type);
4088
4089 return 0;
4090 }
4091 }
4092
4093 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4094 return 0;
4095 }
4096
4097 static int add_plugin(char *plugin_name)
4098 {
4099 static struct pluginfuncs funcs = {
4100 _log,
4101 _log_hex,
4102 fmtaddr,
4103 sessionbyuser,
4104 sessiontbysessionidt,
4105 sessionidtbysessiont,
4106 radiusnew,
4107 radiussend,
4108 getconfig,
4109 sessionkill,
4110 throttle_session,
4111 cluster_send_session,
4112 };
4113
4114 void *p = open_plugin(plugin_name, 1);
4115 int (*initfunc)(struct pluginfuncs *);
4116 int i;
4117
4118 if (!p)
4119 {
4120 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4121 return -1;
4122 }
4123
4124 if (ll_contains(loaded_plugins, p))
4125 {
4126 dlclose(p);
4127 return 0; // already loaded
4128 }
4129
4130 {
4131 int *v = dlsym(p, "plugin_api_version");
4132 if (!v || *v != PLUGIN_API_VERSION)
4133 {
4134 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4135 dlclose(p);
4136 return -1;
4137 }
4138 }
4139
4140 if ((initfunc = dlsym(p, "plugin_init")))
4141 {
4142 if (!initfunc(&funcs))
4143 {
4144 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4145 dlclose(p);
4146 return -1;
4147 }
4148 }
4149
4150 ll_push(loaded_plugins, p);
4151
4152 for (i = 0; i < max_plugin_functions; i++)
4153 {
4154 void *x;
4155 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4156 {
4157 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4158 ll_push(plugins[i], x);
4159 }
4160 }
4161
4162 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4163 return 1;
4164 }
4165
4166 static void run_plugin_done(void *plugin)
4167 {
4168 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4169
4170 if (donefunc)
4171 donefunc();
4172 }
4173
4174 static int remove_plugin(char *plugin_name)
4175 {
4176 void *p = open_plugin(plugin_name, 0);
4177 int loaded = 0;
4178
4179 if (!p)
4180 return -1;
4181
4182 if (ll_contains(loaded_plugins, p))
4183 {
4184 int i;
4185 for (i = 0; i < max_plugin_functions; i++)
4186 {
4187 void *x;
4188 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4189 ll_delete(plugins[i], x);
4190 }
4191
4192 ll_delete(loaded_plugins, p);
4193 run_plugin_done(p);
4194 loaded = 1;
4195 }
4196
4197 dlclose(p);
4198 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4199 return loaded;
4200 }
4201
4202 int run_plugins(int plugin_type, void *data)
4203 {
4204 int (*func)(void *data);
4205
4206 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4207 return PLUGIN_RET_ERROR;
4208
4209 ll_reset(plugins[plugin_type]);
4210 while ((func = ll_next(plugins[plugin_type])))
4211 {
4212 int r = func(data);
4213
4214 if (r != PLUGIN_RET_OK)
4215 return r; // stop here
4216 }
4217
4218 return PLUGIN_RET_OK;
4219 }
4220
4221 static void plugins_done()
4222 {
4223 void *p;
4224
4225 ll_reset(loaded_plugins);
4226 while ((p = ll_next(loaded_plugins)))
4227 run_plugin_done(p);
4228 }
4229
4230 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4231 {
4232 struct nsctl request;
4233 struct nsctl response;
4234 int type = unpack_control(&request, buf, len);
4235 int r;
4236 void *p;
4237
4238 if (log_stream && config->debug >= 4)
4239 {
4240 if (type < 0)
4241 {
4242 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4243 fmtaddr(addr->sin_addr.s_addr, 0), type);
4244 }
4245 else
4246 {
4247 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4248 dump_control(&request, log_stream);
4249 }
4250 }
4251
4252 switch (type)
4253 {
4254 case NSCTL_REQ_LOAD:
4255 if (request.argc != 1)
4256 {
4257 response.type = NSCTL_RES_ERR;
4258 response.argc = 1;
4259 response.argv[0] = "name of plugin required";
4260 }
4261 else if ((r = add_plugin(request.argv[0])) < 1)
4262 {
4263 response.type = NSCTL_RES_ERR;
4264 response.argc = 1;
4265 response.argv[0] = !r
4266 ? "plugin already loaded"
4267 : "error loading plugin";
4268 }
4269 else
4270 {
4271 response.type = NSCTL_RES_OK;
4272 response.argc = 0;
4273 }
4274
4275 break;
4276
4277 case NSCTL_REQ_UNLOAD:
4278 if (request.argc != 1)
4279 {
4280 response.type = NSCTL_RES_ERR;
4281 response.argc = 1;
4282 response.argv[0] = "name of plugin required";
4283 }
4284 else if ((r = remove_plugin(request.argv[0])) < 1)
4285 {
4286 response.type = NSCTL_RES_ERR;
4287 response.argc = 1;
4288 response.argv[0] = !r
4289 ? "plugin not loaded"
4290 : "plugin not found";
4291 }
4292 else
4293 {
4294 response.type = NSCTL_RES_OK;
4295 response.argc = 0;
4296 }
4297
4298 break;
4299
4300 case NSCTL_REQ_HELP:
4301 response.type = NSCTL_RES_OK;
4302 response.argc = 0;
4303
4304 ll_reset(loaded_plugins);
4305 while ((p = ll_next(loaded_plugins)))
4306 {
4307 char **help = dlsym(p, "plugin_control_help");
4308 while (response.argc < 0xff && help && *help)
4309 response.argv[response.argc++] = *help++;
4310 }
4311
4312 break;
4313
4314 case NSCTL_REQ_CONTROL:
4315 {
4316 struct param_control param = {
4317 config->cluster_iam_master,
4318 request.argc,
4319 request.argv,
4320 0,
4321 NULL,
4322 };
4323
4324 int r = run_plugins(PLUGIN_CONTROL, &param);
4325
4326 if (r == PLUGIN_RET_ERROR)
4327 {
4328 response.type = NSCTL_RES_ERR;
4329 response.argc = 1;
4330 response.argv[0] = param.additional
4331 ? param.additional
4332 : "error returned by plugin";
4333 }
4334 else if (r == PLUGIN_RET_NOTMASTER)
4335 {
4336 static char msg[] = "must be run on master: 000.000.000.000";
4337
4338 response.type = NSCTL_RES_ERR;
4339 response.argc = 1;
4340 if (config->cluster_master_address)
4341 {
4342 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4343 response.argv[0] = msg;
4344 }
4345 else
4346 {
4347 response.argv[0] = "must be run on master: none elected";
4348 }
4349 }
4350 else if (!(param.response & NSCTL_RESPONSE))
4351 {
4352 response.type = NSCTL_RES_ERR;
4353 response.argc = 1;
4354 response.argv[0] = param.response
4355 ? "unrecognised response value from plugin"
4356 : "unhandled action";
4357 }
4358 else
4359 {
4360 response.type = param.response;
4361 response.argc = 0;
4362 if (param.additional)
4363 {
4364 response.argc = 1;
4365 response.argv[0] = param.additional;
4366 }
4367 }
4368 }
4369
4370 break;
4371
4372 default:
4373 response.type = NSCTL_RES_ERR;
4374 response.argc = 1;
4375 response.argv[0] = "error unpacking control packet";
4376 }
4377
4378 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4379 if (!buf)
4380 {
4381 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4382 return;
4383 }
4384
4385 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4386 if (r > 0)
4387 {
4388 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4389 if (log_stream && config->debug >= 4)
4390 {
4391 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4392 dump_control(&response, log_stream);
4393 }
4394 }
4395 else
4396 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4397 fmtaddr(addr->sin_addr.s_addr, 0), r);
4398
4399 free(buf);
4400 }
4401
4402 static tunnelidt new_tunnel()
4403 {
4404 tunnelidt i;
4405 for (i = 1; i < MAXTUNNEL; i++)
4406 {
4407 if (tunnel[i].state == TUNNELFREE)
4408 {
4409 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4410 if (i > config->cluster_highest_tunnelid)
4411 config->cluster_highest_tunnelid = i;
4412 return i;
4413 }
4414 }
4415 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4416 return 0;
4417 }
4418
4419 //
4420 // We're becoming the master. Do any required setup..
4421 //
4422 // This is principally telling all the plugins that we're
4423 // now a master, and telling them about all the sessions
4424 // that are active too..
4425 //
4426 void become_master(void)
4427 {
4428 int s, i;
4429 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4430
4431 // running a bunch of iptables commands is slow and can cause
4432 // the master to drop tunnels on takeover--kludge around the
4433 // problem by forking for the moment (note: race)
4434 if (!fork_and_close())
4435 {
4436 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4437 {
4438 if (!session[s].opened) // Not an in-use session.
4439 continue;
4440
4441 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4442 }
4443 exit(0);
4444 }
4445
4446 // add radius fds
4447 for (i = 0; i < config->num_radfds; i++)
4448 {
4449 FD_SET(radfds[i], &readset);
4450 if (radfds[i] > readset_n)
4451 readset_n = radfds[i];
4452 }
4453 }
4454
4455 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4456 {
4457 int s, i;
4458 int count = 0;
4459 int buckets[64];
4460
4461 if (CLI_HELP_REQUESTED)
4462 return CLI_HELP_NO_ARGS;
4463
4464 time(&time_now);
4465 for (i = 0; i < 64;++i) buckets[i] = 0;
4466
4467 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4468 {
4469 int idle;
4470 if (!session[s].opened)
4471 continue;
4472
4473 idle = time_now - session[s].last_packet;
4474 idle /= 5 ; // In multiples of 5 seconds.
4475 if (idle < 0)
4476 idle = 0;
4477 if (idle > 63)
4478 idle = 63;
4479
4480 ++count;
4481 ++buckets[idle];
4482 }
4483
4484 for (i = 0; i < 63; ++i)
4485 {
4486 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4487 }
4488 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4489 cli_print(cli, "%d total sessions open.", count);
4490 return CLI_OK;
4491 }
4492
4493 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4494 {
4495 int s, i;
4496 int count = 0;
4497 int buckets[64];
4498
4499 if (CLI_HELP_REQUESTED)
4500 return CLI_HELP_NO_ARGS;
4501
4502 time(&time_now);
4503 for (i = 0; i < 64;++i) buckets[i] = 0;
4504
4505 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4506 {
4507 int open = 0, d;
4508 if (!session[s].opened)
4509 continue;
4510
4511 d = time_now - session[s].opened;
4512 if (d < 0)
4513 d = 0;
4514 while (d > 1 && open < 32)
4515 {
4516 ++open;
4517 d >>= 1; // half.
4518 }
4519 ++count;
4520 ++buckets[open];
4521 }
4522
4523 s = 1;
4524 for (i = 0; i < 30; ++i)
4525 {
4526 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4527 s <<= 1;
4528 }
4529 cli_print(cli, "%d total sessions open.", count);
4530 return CLI_OK;
4531 }
4532
4533 /* Unhide an avp.
4534 *
4535 * This unencodes the AVP using the L2TP CHAP secret and the
4536 * previously stored random vector. It replaces the hidden data with
4537 * the cleartext data and returns the length of the cleartext data
4538 * (including the AVP "header" of 6 bytes).
4539 *
4540 * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
4541 */
4542 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
4543 {
4544 MD5_CTX ctx;
4545 uint8_t *cursor;
4546 uint8_t digest[16];
4547 uint8_t working_vector[16];
4548 uint16_t hidden_length;
4549 uint8_t type[2];
4550 size_t done, todo;
4551 uint8_t *output;
4552
4553 // Find the AVP type.
4554 type[0] = *(avp + 4);
4555 type[1] = *(avp + 5);
4556
4557 // Line up with the hidden data
4558 cursor = output = avp + 6;
4559
4560 // Compute initial pad
4561 MD5Init(&ctx);
4562 MD5Update(&ctx, type, 2);
4563 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4564 MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
4565 MD5Final(digest, &ctx);
4566
4567 // Get hidden length
4568 hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
4569
4570 // Keep these for later use
4571 working_vector[0] = *cursor;
4572 working_vector[1] = *(cursor + 1);
4573 cursor += 2;
4574
4575 if (hidden_length > length - 8)
4576 {
4577 LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
4578 return 0;
4579 }
4580
4581 /* Decrypt remainder */
4582 done = 2;
4583 todo = hidden_length;
4584 while (todo)
4585 {
4586 working_vector[done] = *cursor;
4587 *output = digest[done] ^ *cursor;
4588 ++output;
4589 ++cursor;
4590 --todo;
4591 ++done;
4592 if (done == 16 && todo)
4593 {
4594 // Compute new digest
4595 done = 0;
4596 MD5Init(&ctx);
4597 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4598 MD5Update(&ctx, &working_vector, 16);
4599 MD5Final(digest, &ctx);
4600 }
4601 }
4602
4603 return hidden_length + 6;
4604 }
4605
4606 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
4607 {
4608 switch (p->op)
4609 {
4610 case FILTER_PORT_OP_EQ: return port == p->port;
4611 case FILTER_PORT_OP_NEQ: return port != p->port;
4612 case FILTER_PORT_OP_GT: return port > p->port;
4613 case FILTER_PORT_OP_LT: return port < p->port;
4614 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
4615 }
4616
4617 return 0;
4618 }
4619
4620 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
4621 {
4622 switch (op)
4623 {
4624 case FILTER_FLAG_OP_ANY:
4625 return (flags & sflags) || (~flags & cflags);
4626
4627 case FILTER_FLAG_OP_ALL:
4628 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
4629
4630 case FILTER_FLAG_OP_EST:
4631 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
4632 }
4633
4634 return 0;
4635 }
4636
4637 int ip_filter(uint8_t *buf, int len, uint8_t filter)
4638 {
4639 uint16_t frag_offset;
4640 uint8_t proto;
4641 in_addr_t src_ip;
4642 in_addr_t dst_ip;
4643 uint16_t src_port = 0;
4644 uint16_t dst_port = 0;
4645 uint8_t flags = 0;
4646 ip_filter_rulet *rule;
4647
4648 if (len < 20) // up to end of destination address
4649 return 0;
4650
4651 if ((*buf >> 4) != 4) // IPv4
4652 return 0;
4653
4654 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
4655 proto = buf[9];
4656 src_ip = *(in_addr_t *) (buf + 12);
4657 dst_ip = *(in_addr_t *) (buf + 16);
4658
4659 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
4660 {
4661 int l = (buf[0] & 0xf) * 4; // length of IP header
4662 if (len < l + 4) // ports
4663 return 0;
4664
4665 src_port = ntohs(*(uint16_t *) (buf + l));
4666 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
4667 if (proto == IPPROTO_TCP)
4668 {
4669 if (len < l + 14) // flags
4670 return 0;
4671
4672 flags = buf[l + 13] & 0x3f;
4673 }
4674 }
4675
4676 for (rule = ip_filters[filter].rules; rule->action; rule++)
4677 {
4678 if (rule->proto != IPPROTO_IP && proto != rule->proto)
4679 continue;
4680
4681 if (rule->src_wild != INADDR_BROADCAST &&
4682 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
4683 continue;
4684
4685 if (rule->dst_wild != INADDR_BROADCAST &&
4686 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
4687 continue;
4688
4689 if (frag_offset)
4690 {
4691 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
4692 continue;
4693 }
4694 else
4695 {
4696 if (rule->frag)
4697 continue;
4698
4699 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
4700 {
4701 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
4702 continue;
4703
4704 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
4705 continue;
4706
4707 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
4708 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
4709 continue;
4710 }
4711 }
4712
4713 // matched
4714 rule->counter++;
4715 return rule->action == FILTER_ACTION_PERMIT;
4716 }
4717
4718 // default deny
4719 return 0;
4720 }