341cf7475dd9ae442394fc1f37c45e2c92ab10c9
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.72 2004/12/16 23:40:31 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 static 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("cleanup_interval", cleanup_interval, INT),
116 CONFIG("multi_read_count", multi_read_count, INT),
117 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
118 CONFIG("lock_pages", lock_pages, BOOL),
119 CONFIG("icmp_rate", icmp_rate, 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 { NULL, 0, 0, 0 },
125 };
126
127 static char *plugin_functions[] = {
128 NULL,
129 "plugin_pre_auth",
130 "plugin_post_auth",
131 "plugin_packet_rx",
132 "plugin_packet_tx",
133 "plugin_timer",
134 "plugin_new_session",
135 "plugin_kill_session",
136 "plugin_control",
137 "plugin_radius_response",
138 "plugin_become_master",
139 "plugin_new_session_master",
140 };
141
142 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
143
144 // Counters for shutdown sessions
145 static sessiont shut_acct[8192];
146 static sessionidt shut_acct_n = 0;
147
148 tunnelt *tunnel = NULL; // Array of tunnel structures.
149 sessiont *session = NULL; // Array of session structures.
150 sessioncountt *sess_count = NULL; // Array of partial per-session traffic counters.
151 radiust *radius = NULL; // Array of radius structures.
152 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
153 ip_filtert *ip_filters = NULL; // Array of named filters.
154 static controlt *controlfree = 0;
155 struct Tstats *_statistics = NULL;
156 #ifdef RINGBUFFER
157 struct Tringbuffer *ringbuffer = NULL;
158 #endif
159
160 static void cache_ipmap(in_addr_t ip, int s);
161 static void uncache_ipmap(in_addr_t ip);
162 static void free_ip_address(sessionidt s);
163 static void dump_acct_info(int all);
164 static void sighup_handler(int sig);
165 static void sigalrm_handler(int sig);
166 static void sigterm_handler(int sig);
167 static void sigquit_handler(int sig);
168 static void sigchild_handler(int sig);
169 static void read_state(void);
170 static void dump_state(void);
171 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
172 static void update_config(void);
173 static void read_config_file(void);
174 static void initplugins(void);
175 static int add_plugin(char *plugin_name);
176 static int remove_plugin(char *plugin_name);
177 static void plugins_done(void);
178 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
179 static tunnelidt new_tunnel(void);
180 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
181
182 // return internal time (10ths since process startup)
183 static clockt now(void)
184 {
185 struct timeval t;
186 gettimeofday(&t, 0);
187 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
188 }
189
190 // work out a retry time based on try number
191 // This is a straight bounded exponential backoff.
192 // Maximum re-try time is 32 seconds. (2^5).
193 clockt backoff(uint8_t try)
194 {
195 if (try > 5) try = 5; // max backoff
196 return now() + 10 * (1 << try);
197 }
198
199
200 //
201 // Log a debug message. Typically called via the LOG macro
202 //
203 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
204 {
205 static char message[65536] = {0};
206 static char message2[65536] = {0};
207 va_list ap;
208
209 #ifdef RINGBUFFER
210 if (ringbuffer)
211 {
212 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
213 ringbuffer->tail = 0;
214 if (ringbuffer->tail == ringbuffer->head)
215 if (++ringbuffer->head >= RINGBUFFER_SIZE)
216 ringbuffer->head = 0;
217
218 ringbuffer->buffer[ringbuffer->tail].level = level;
219 ringbuffer->buffer[ringbuffer->tail].session = s;
220 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
221 va_start(ap, format);
222 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
223 va_end(ap);
224 }
225 #endif
226
227 if (config->debug < level) return;
228
229 va_start(ap, format);
230 if (log_stream)
231 {
232 vsnprintf(message2, 65535, format, ap);
233 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
234 fprintf(log_stream, "%s", message);
235 }
236 else if (syslog_log)
237 {
238 vsnprintf(message2, 65535, format, ap);
239 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
240 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
241 }
242 va_end(ap);
243 }
244
245 void _log_hex(int level, const char *title, const char *data, int maxsize)
246 {
247 int i, j;
248 const uint8_t *d = (const uint8_t *) data;
249
250 if (config->debug < level) return;
251
252 // No support for _log_hex to syslog
253 if (log_stream)
254 {
255 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
256 setvbuf(log_stream, NULL, _IOFBF, 16384);
257
258 for (i = 0; i < maxsize; )
259 {
260 fprintf(log_stream, "%4X: ", i);
261 for (j = i; j < maxsize && j < (i + 16); j++)
262 {
263 fprintf(log_stream, "%02X ", d[j]);
264 if (j == i + 7)
265 fputs(": ", log_stream);
266 }
267
268 for (; j < i + 16; j++)
269 {
270 fputs(" ", log_stream);
271 if (j == i + 7)
272 fputs(": ", log_stream);
273 }
274
275 fputs(" ", log_stream);
276 for (j = i; j < maxsize && j < (i + 16); j++)
277 {
278 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
279 fputc(d[j], log_stream);
280 else
281 fputc('.', log_stream);
282
283 if (j == i + 7)
284 fputs(" ", log_stream);
285 }
286
287 i = j;
288 fputs("\n", log_stream);
289 }
290
291 fflush(log_stream);
292 setbuf(log_stream, NULL);
293 }
294 }
295
296
297 // Add a route
298 //
299 // This adds it to the routing table, advertises it
300 // via BGP if enabled, and stuffs it into the
301 // 'sessionbyip' cache.
302 //
303 // 'ip' and 'mask' must be in _host_ order.
304 //
305 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
306 {
307 struct rtentry r;
308 int i;
309
310 if (!mask) mask = 0xffffffff;
311
312 ip &= mask; // Force the ip to be the first one in the route.
313
314 memset(&r, 0, sizeof(r));
315 r.rt_dev = config->tundevice;
316 r.rt_dst.sa_family = AF_INET;
317 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
318 r.rt_gateway.sa_family = AF_INET;
319 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
320 r.rt_genmask.sa_family = AF_INET;
321 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
322 r.rt_flags = (RTF_UP | RTF_STATIC);
323 if (gw)
324 r.rt_flags |= RTF_GATEWAY;
325 else if (mask == 0xffffffff)
326 r.rt_flags |= RTF_HOST;
327
328 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
329 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
330 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
331
332 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
333 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
334
335 #ifdef BGP
336 if (add)
337 bgp_add_route(htonl(ip), htonl(mask));
338 else
339 bgp_del_route(htonl(ip), htonl(mask));
340 #endif /* BGP */
341
342 // Add/Remove the IPs to the 'sessionbyip' cache.
343 // Note that we add the zero address in the case of
344 // a network route. Roll on CIDR.
345
346 // Note that 's == 0' implies this is the address pool.
347 // We still cache it here, because it will pre-fill
348 // the malloc'ed tree.
349
350 if (s)
351 {
352 if (!add) // Are we deleting a route?
353 s = 0; // Caching the session as '0' is the same as uncaching.
354
355 for (i = ip; (i&mask) == (ip&mask) ; ++i)
356 cache_ipmap(i, s);
357 }
358 }
359
360 //
361 // Set up TUN interface
362 static void inittun(void)
363 {
364 struct ifreq ifr;
365 struct sockaddr_in sin = {0};
366 memset(&ifr, 0, sizeof(ifr));
367 ifr.ifr_flags = IFF_TUN;
368
369 tunfd = open(TUNDEVICE, O_RDWR);
370 if (tunfd < 0)
371 { // fatal
372 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
373 exit(1);
374 }
375 {
376 int flags = fcntl(tunfd, F_GETFL, 0);
377 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
378 }
379 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
380 {
381 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
382 exit(1);
383 }
384 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
385 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
386 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
387
388 sin.sin_family = AF_INET;
389 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
390 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
391
392 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
393 {
394 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
395 exit(1);
396 }
397 /* Bump up the qlen to deal with bursts from the network */
398 ifr.ifr_qlen = 1000;
399 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
400 {
401 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
402 exit(1);
403 }
404 ifr.ifr_flags = IFF_UP;
405 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
406 {
407 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
408 exit(1);
409 }
410 }
411
412 // set up UDP port
413 static void initudp(void)
414 {
415 int on = 1;
416 struct sockaddr_in addr;
417
418 // Tunnel
419 memset(&addr, 0, sizeof(addr));
420 addr.sin_family = AF_INET;
421 addr.sin_port = htons(L2TPPORT);
422 addr.sin_addr.s_addr = config->bind_address;
423 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
424 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
425 {
426 int flags = fcntl(udpfd, F_GETFL, 0);
427 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
428 }
429 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
430 {
431 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
432 exit(1);
433 }
434 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
435
436 // Control
437 memset(&addr, 0, sizeof(addr));
438 addr.sin_family = AF_INET;
439 addr.sin_port = htons(NSCTL_PORT);
440 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
441 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
442 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
443 {
444 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
445 exit(1);
446 }
447 }
448
449 //
450 // Find session by IP, < 1 for not found
451 //
452 // Confusingly enough, this 'ip' must be
453 // in _network_ order. This being the common
454 // case when looking it up from IP packet headers.
455 //
456 // We actually use this cache for two things.
457 // #1. For used IP addresses, this maps to the
458 // session ID that it's used by.
459 // #2. For un-used IP addresses, this maps to the
460 // index into the pool table that contains that
461 // IP address.
462 //
463
464 static int lookup_ipmap(in_addr_t ip)
465 {
466 uint8_t *a = (uint8_t *) &ip;
467 uint8_t **d = (uint8_t **) ip_hash;
468
469 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
470 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
471 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
472
473 return (int) (intptr_t) d[(size_t) *a];
474 }
475
476 sessionidt sessionbyip(in_addr_t ip)
477 {
478 int s = lookup_ipmap(ip);
479 CSTAT(call_sessionbyip);
480
481 if (s > 0 && s < MAXSESSION && session[s].tunnel)
482 return (sessionidt) s;
483
484 return 0;
485 }
486
487 //
488 // Take an IP address in HOST byte order and
489 // add it to the sessionid by IP cache.
490 //
491 // (It's actually cached in network order)
492 //
493 static void cache_ipmap(in_addr_t ip, int s)
494 {
495 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
496 uint8_t *a = (uint8_t *) &nip;
497 uint8_t **d = (uint8_t **) ip_hash;
498 int i;
499
500 for (i = 0; i < 3; i++)
501 {
502 if (!d[(size_t) a[i]])
503 {
504 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
505 return;
506 }
507
508 d = (uint8_t **) d[(size_t) a[i]];
509 }
510
511 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
512
513 if (s > 0)
514 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
515
516 else if (s == 0)
517 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
518 // else a map to an ip pool index.
519 }
520
521 static void uncache_ipmap(in_addr_t ip)
522 {
523 cache_ipmap(ip, 0); // Assign it to the NULL session.
524 }
525
526 //
527 // CLI list to dump current ipcache.
528 //
529 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
530 {
531 char **d = (char **) ip_hash, **e, **f, **g;
532 int i, j, k, l;
533 int count = 0;
534
535 if (CLI_HELP_REQUESTED)
536 return CLI_HELP_NO_ARGS;
537
538 cli_print(cli, "%7s %s", "Sess#", "IP Address");
539
540 for (i = 0; i < 256; ++i)
541 {
542 if (!d[i])
543 continue;
544 e = (char **) d[i];
545 for (j = 0; j < 256; ++j)
546 {
547 if (!e[j])
548 continue;
549 f = (char **) e[j];
550 for (k = 0; k < 256; ++k)
551 {
552 if (!f[k])
553 continue;
554 g = (char **)f[k];
555 for (l = 0; l < 256; ++l)
556 {
557 if (!g[l])
558 continue;
559 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
560 ++count;
561 }
562 }
563 }
564 }
565 cli_print(cli, "%d entries in cache", count);
566 return CLI_OK;
567 }
568
569
570 // Find session by username, 0 for not found
571 // walled garden users aren't authenticated, so the username is
572 // reasonably useless. Ignore them to avoid incorrect actions
573 //
574 // This is VERY inefficent. Don't call it often. :)
575 //
576 sessionidt sessionbyuser(char *username)
577 {
578 int s;
579 CSTAT(call_sessionbyuser);
580
581 for (s = 1; s < MAXSESSION ; ++s)
582 {
583 if (session[s].walled_garden)
584 continue; // Skip walled garden users.
585
586 if (!strncmp(session[s].user, username, 128))
587 return s;
588
589 }
590 return 0; // Not found.
591 }
592
593 void send_garp(in_addr_t ip)
594 {
595 int s;
596 struct ifreq ifr;
597 uint8_t mac[6];
598
599 s = socket(PF_INET, SOCK_DGRAM, 0);
600 if (s < 0)
601 {
602 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
603 return;
604 }
605 memset(&ifr, 0, sizeof(ifr));
606 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
607 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
608 {
609 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
610 close(s);
611 return;
612 }
613 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
614 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
615 {
616 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
617 close(s);
618 return;
619 }
620 close(s);
621 sendarp(ifr.ifr_ifindex, mac, ip);
622 }
623
624 // Find session by username, 0 for not found
625 static sessiont *sessiontbysessionidt(sessionidt s)
626 {
627 if (!s || s > MAXSESSION) return NULL;
628 return &session[s];
629 }
630
631 static sessionidt sessionidtbysessiont(sessiont *s)
632 {
633 sessionidt val = s-session;
634 if (s < session || val > MAXSESSION) return 0;
635 return val;
636 }
637
638 // actually send a control message for a specific tunnel
639 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
640 {
641 struct sockaddr_in addr;
642
643 CSTAT(call_tunnelsend);
644
645 if (!t)
646 {
647 static int backtrace_count = 0;
648 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
649 STAT(tunnel_tx_errors);
650 log_backtrace(backtrace_count, 5)
651 return;
652 }
653
654 if (!tunnel[t].ip)
655 {
656 static int backtrace_count = 0;
657 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
658 log_backtrace(backtrace_count, 5)
659 STAT(tunnel_tx_errors);
660 return;
661 }
662
663 memset(&addr, 0, sizeof(addr));
664 addr.sin_family = AF_INET;
665 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
666 addr.sin_port = htons(tunnel[t].port);
667
668 // sequence expected, if sequence in message
669 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
670
671 // If this is a control message, deal with retries
672 if (*buf & 0x80)
673 {
674 tunnel[t].last = time_now; // control message sent
675 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
676 if (tunnel[t].try > 1)
677 {
678 STAT(tunnel_retries);
679 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
680 }
681 }
682
683 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
684 {
685 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
686 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
687 STAT(tunnel_tx_errors);
688 return;
689 }
690
691 LOG_HEX(5, "Send Tunnel Data", buf, l);
692 STAT(tunnel_tx_packets);
693 INC_STAT(tunnel_tx_bytes, l);
694 }
695
696 //
697 // Tiny helper function to write data to
698 // the 'tun' device.
699 //
700 int tun_write(uint8_t * data, int size)
701 {
702 return write(tunfd, data, size);
703 }
704
705 // process outgoing (to tunnel) IP
706 //
707 static void processipout(uint8_t * buf, int len)
708 {
709 sessionidt s;
710 sessiont *sp;
711 tunnelidt t;
712 in_addr_t ip;
713
714 char * data = buf; // Keep a copy of the originals.
715 int size = len;
716
717 uint8_t b[MAXETHER + 20];
718
719 CSTAT(call_processipout);
720
721 if (len < MIN_IP_SIZE)
722 {
723 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
724 STAT(tunnel_tx_errors);
725 return;
726 }
727 if (len >= MAXETHER)
728 {
729 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
730 STAT(tunnel_tx_errors);
731 return;
732 }
733
734 // Skip the tun header
735 buf += 4;
736 len -= 4;
737
738 // Got an IP header now
739 if (*(uint8_t *)(buf) >> 4 != 4)
740 {
741 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
742 return;
743 }
744
745 ip = *(uint32_t *)(buf + 16);
746 if (!(s = sessionbyip(ip)))
747 {
748 // Is this a packet for a session that doesn't exist?
749 static int rate = 0; // Number of ICMP packets we've sent this second.
750 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
751
752 if (last != time_now)
753 {
754 last = time_now;
755 rate = 0;
756 }
757
758 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
759 {
760 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
761 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
762 }
763 return;
764 }
765 t = session[s].tunnel;
766 sp = &session[s];
767
768 // run access-list if any
769 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
770 return;
771
772 if (sp->tbf_out)
773 {
774 // Are we throttling this session?
775 if (config->cluster_iam_master)
776 tbf_queue_packet(sp->tbf_out, data, size);
777 else
778 master_throttle_packet(sp->tbf_out, data, size);
779 return;
780 }
781 else if (sp->walled_garden && !config->cluster_iam_master)
782 {
783 // We are walled-gardening this
784 master_garden_packet(s, data, size);
785 return;
786 }
787
788 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
789
790 // Add on L2TP header
791 {
792 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
793 if (!p) return;
794 tunnelsend(b, len + (p-b), t); // send it...
795 }
796
797 // Snooping this session, send it to intercept box
798 if (sp->snoop_ip && sp->snoop_port)
799 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
800
801 sp->cout += len; // byte count
802 sp->total_cout += len; // byte count
803 sp->pout++;
804 udp_tx += len;
805 sess_count[s].cout += len; // To send to master..
806 }
807
808 //
809 // Helper routine for the TBF filters.
810 // Used to send queued data in to the user!
811 //
812 static void send_ipout(sessionidt s, uint8_t *buf, int len)
813 {
814 sessiont *sp;
815 tunnelidt t;
816 in_addr_t ip;
817
818 uint8_t b[MAXETHER + 20];
819
820 if (len < 0 || len > MAXETHER)
821 {
822 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
823 return;
824 }
825
826 // Skip the tun header
827 buf += 4;
828 len -= 4;
829
830 ip = *(in_addr_t *)(buf + 16);
831
832 if (!session[s].ip)
833 return;
834
835 t = session[s].tunnel;
836 sp = &session[s];
837
838 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
839
840 // Add on L2TP header
841 {
842 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
843 if (!p) return;
844 tunnelsend(b, len + (p-b), t); // send it...
845 }
846
847 // Snooping this session.
848 if (sp->snoop_ip && sp->snoop_port)
849 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
850
851 sp->cout += len; // byte count
852 sp->total_cout += len; // byte count
853 sp->pout++;
854 udp_tx += len;
855 sess_count[s].cout += len; // To send to master..
856 }
857
858 // add an AVP (16 bit)
859 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
860 {
861 uint16_t l = (m ? 0x8008 : 0x0008);
862 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
863 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
864 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
865 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
866 c->length += 8;
867 }
868
869 // add an AVP (32 bit)
870 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
871 {
872 uint16_t l = (m ? 0x800A : 0x000A);
873 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
874 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
875 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
876 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
877 c->length += 10;
878 }
879
880 // add an AVP (32 bit)
881 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
882 {
883 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
884 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
885 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
886 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
887 memcpy(c->buf + c->length + 6, val, strlen(val));
888 c->length += 6 + strlen(val);
889 }
890
891 // add a binary AVP
892 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
893 {
894 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
895 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
896 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
897 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
898 memcpy(c->buf + c->length + 6, val, len);
899 c->length += 6 + len;
900 }
901
902 // new control connection
903 static controlt *controlnew(uint16_t mtype)
904 {
905 controlt *c;
906 if (!controlfree)
907 c = malloc(sizeof(controlt));
908 else
909 {
910 c = controlfree;
911 controlfree = c->next;
912 }
913 assert(c);
914 c->next = 0;
915 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
916 c->length = 12;
917 control16(c, 0, mtype, 1);
918 return c;
919 }
920
921 // send zero block if nothing is waiting
922 // (ZLB send).
923 static void controlnull(tunnelidt t)
924 {
925 uint8_t buf[12];
926 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
927 return;
928
929 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
930 *(uint16_t *) (buf + 2) = htons(12); // length
931 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
932 *(uint16_t *) (buf + 6) = htons(0); // session
933 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
934 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
935 tunnelsend(buf, 12, t);
936 }
937
938 // add a control message to a tunnel, and send if within window
939 static void controladd(controlt * c, tunnelidt t, sessionidt s)
940 {
941 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
942 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
943 *(uint16_t *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
944 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
945 tunnel[t].ns++; // advance sequence
946 // link in message in to queue
947 if (tunnel[t].controlc)
948 tunnel[t].controle->next = c;
949 else
950 tunnel[t].controls = c;
951
952 tunnel[t].controle = c;
953 tunnel[t].controlc++;
954
955 // send now if space in window
956 if (tunnel[t].controlc <= tunnel[t].window)
957 {
958 tunnel[t].try = 0; // first send
959 tunnelsend(c->buf, c->length, t);
960 }
961 }
962
963 //
964 // Throttle or Unthrottle a session
965 //
966 // Throttle the data from/to through a session to no more than
967 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
968 // user).
969 //
970 // If either value is -1, the current value is retained for that
971 // direction.
972 //
973 void throttle_session(sessionidt s, int rate_in, int rate_out)
974 {
975 if (!session[s].tunnel)
976 return; // No-one home.
977
978 if (!*session[s].user)
979 return; // User not logged in
980
981 if (rate_in >= 0)
982 {
983 int bytes = rate_in * 1024 / 8; // kbits to bytes
984 if (session[s].tbf_in)
985 free_tbf(session[s].tbf_in);
986
987 if (rate_in > 0)
988 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
989 else
990 session[s].tbf_in = 0;
991
992 session[s].throttle_in = rate_in;
993 }
994
995 if (rate_out >= 0)
996 {
997 int bytes = rate_out * 1024 / 8;
998 if (session[s].tbf_out)
999 free_tbf(session[s].tbf_out);
1000
1001 if (rate_out > 0)
1002 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1003 else
1004 session[s].tbf_out = 0;
1005
1006 session[s].throttle_out = rate_out;
1007 }
1008 }
1009
1010 // add/remove filters from session (-1 = no change)
1011 void filter_session(sessionidt s, int filter_in, int filter_out)
1012 {
1013 if (!session[s].tunnel)
1014 return; // No-one home.
1015
1016 if (!*session[s].user)
1017 return; // User not logged in
1018
1019 // paranoia
1020 if (filter_in > MAXFILTER) filter_in = -1;
1021 if (filter_out > MAXFILTER) filter_out = -1;
1022 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1023 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1024
1025 if (filter_in >= 0)
1026 {
1027 if (session[s].filter_in)
1028 ip_filters[session[s].filter_in - 1].used--;
1029
1030 if (filter_in > 0)
1031 ip_filters[filter_in - 1].used++;
1032
1033 session[s].filter_in = filter_in;
1034 }
1035
1036 if (filter_out >= 0)
1037 {
1038 if (session[s].filter_out)
1039 ip_filters[session[s].filter_out - 1].used--;
1040
1041 if (filter_out > 0)
1042 ip_filters[filter_out - 1].used++;
1043
1044 session[s].filter_out = filter_out;
1045 }
1046 }
1047
1048 // start tidy shutdown of session
1049 void sessionshutdown(sessionidt s, char *reason)
1050 {
1051 int walled_garden = session[s].walled_garden;
1052
1053
1054 CSTAT(call_sessionshutdown);
1055
1056 if (!session[s].tunnel)
1057 {
1058 LOG(3, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1059 return; // not a live session
1060 }
1061
1062 if (!session[s].die)
1063 {
1064 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1065 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1066 run_plugins(PLUGIN_KILL_SESSION, &data);
1067 }
1068
1069 if (session[s].opened && !walled_garden && !session[s].die)
1070 {
1071 // RADIUS Stop message
1072 uint16_t r = session[s].radius;
1073 if (!r)
1074 {
1075 if (!(r = radiusnew(s)))
1076 {
1077 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1078 STAT(radius_overflow);
1079 }
1080 else
1081 {
1082 int n;
1083 for (n = 0; n < 15; n++)
1084 radius[r].auth[n] = rand();
1085 }
1086 }
1087
1088 if (r && radius[r].state != RADIUSSTOP)
1089 radiussend(r, RADIUSSTOP); // stop, if not already trying
1090
1091 // Save counters to dump to accounting file
1092 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1093 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1094 }
1095
1096 if (session[s].ip)
1097 { // IP allocated, clear and unroute
1098 int r;
1099 int routed = 0;
1100 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1101 {
1102 if ((session[s].ip & session[s].route[r].mask) ==
1103 (session[s].route[r].ip & session[s].route[r].mask))
1104 routed++;
1105
1106 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1107 session[s].route[r].ip = 0;
1108 }
1109
1110 if (session[s].ip_pool_index == -1) // static ip
1111 {
1112 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1113 session[s].ip = 0;
1114 }
1115 else
1116 free_ip_address(s);
1117 }
1118
1119 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1120 throttle_session(s, 0, 0);
1121
1122 { // Send CDN
1123 controlt *c = controlnew(14); // sending CDN
1124 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1125 control16(c, 14, s, 1); // assigned session (our end)
1126 controladd(c, session[s].tunnel, s); // send the message
1127 }
1128
1129 if (!session[s].die)
1130 session[s].die = now() + 150; // Clean up in 15 seconds
1131
1132 // update filter refcounts
1133 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1134 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1135
1136 cluster_send_session(s);
1137 }
1138
1139 void sendipcp(tunnelidt t, sessionidt s)
1140 {
1141 uint8_t buf[MAXCONTROL];
1142 uint16_t r = session[s].radius;
1143 uint8_t *q;
1144
1145 CSTAT(call_sendipcp);
1146
1147 if (!r)
1148 r = radiusnew(s);
1149
1150 if (radius[r].state != RADIUSIPCP)
1151 {
1152 radius[r].state = RADIUSIPCP;
1153 radius[r].try = 0;
1154 }
1155
1156 radius[r].retry = backoff(radius[r].try++);
1157 if (radius[r].try > 10)
1158 {
1159 radiusclear(r, s); // Clear radius session.
1160 sessionshutdown(s, "No reply on IPCP");
1161 return;
1162 }
1163
1164 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1165 if (!q) return;
1166
1167 *q = ConfigReq;
1168 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1169 *(uint16_t *) (q + 2) = htons(10);
1170 q[4] = 3;
1171 q[5] = 6;
1172 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1173 config->bind_address ? config->bind_address :
1174 my_address; // send my IP
1175
1176 tunnelsend(buf, 10 + (q - buf), t); // send it
1177 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1178 }
1179
1180 // kill a session now
1181 static void sessionkill(sessionidt s, char *reason)
1182 {
1183
1184 CSTAT(call_sessionkill);
1185
1186 session[s].die = now();
1187 sessionshutdown(s, reason); // close radius/routes, etc.
1188 if (session[s].radius)
1189 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1190
1191 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1192
1193 memset(&session[s], 0, sizeof(session[s]));
1194 session[s].tunnel = T_FREE; // Mark it as free.
1195 session[s].next = sessionfree;
1196 sessionfree = s;
1197 cli_session_actions[s].action = 0;
1198 cluster_send_session(s);
1199 }
1200
1201 static void tunnelclear(tunnelidt t)
1202 {
1203 if (!t) return;
1204 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1205 tunnel[t].state = TUNNELFREE;
1206 }
1207
1208 // kill a tunnel now
1209 static void tunnelkill(tunnelidt t, char *reason)
1210 {
1211 sessionidt s;
1212 controlt *c;
1213
1214 CSTAT(call_tunnelkill);
1215
1216 tunnel[t].state = TUNNELDIE;
1217
1218 // free control messages
1219 while ((c = tunnel[t].controls))
1220 {
1221 controlt * n = c->next;
1222 tunnel[t].controls = n;
1223 tunnel[t].controlc--;
1224 c->next = controlfree;
1225 controlfree = c;
1226 }
1227 // kill sessions
1228 for (s = 1; s < MAXSESSION; s++)
1229 if (session[s].tunnel == t)
1230 sessionkill(s, reason);
1231
1232 // free tunnel
1233 tunnelclear(t);
1234 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1235 cli_tunnel_actions[s].action = 0;
1236 cluster_send_tunnel(t);
1237 }
1238
1239 // shut down a tunnel cleanly
1240 static void tunnelshutdown(tunnelidt t, char *reason)
1241 {
1242 sessionidt s;
1243
1244 CSTAT(call_tunnelshutdown);
1245
1246 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1247 {
1248 // never set up, can immediately kill
1249 tunnelkill(t, reason);
1250 return;
1251 }
1252 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1253
1254 // close session
1255 for (s = 1; s < MAXSESSION; s++)
1256 if (session[s].tunnel == t)
1257 sessionshutdown(s, reason);
1258
1259 tunnel[t].state = TUNNELDIE;
1260 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1261 cluster_send_tunnel(t);
1262 // TBA - should we wait for sessions to stop?
1263 { // Send StopCCN
1264 controlt *c = controlnew(4); // sending StopCCN
1265 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message)
1266 control16(c, 9, t, 1); // assigned tunnel (our end)
1267 controladd(c, t, 0); // send the message
1268 }
1269 }
1270
1271 // read and process packet on tunnel (UDP)
1272 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1273 {
1274 char *chapresponse = NULL;
1275 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1276 uint8_t *p = buf + 2;
1277
1278
1279 CSTAT(call_processudp);
1280
1281 udp_rx += len;
1282 udp_rx_pkt++;
1283 LOG_HEX(5, "UDP Data", buf, len);
1284 STAT(tunnel_rx_packets);
1285 INC_STAT(tunnel_rx_bytes, len);
1286 if (len < 6)
1287 {
1288 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1289 STAT(tunnel_rx_errors);
1290 return;
1291 }
1292 if ((buf[1] & 0x0F) != 2)
1293 {
1294 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1295 STAT(tunnel_rx_errors);
1296 return;
1297 }
1298 if (*buf & 0x40)
1299 { // length
1300 l = ntohs(*(uint16_t *) p);
1301 p += 2;
1302 }
1303 t = ntohs(*(uint16_t *) p);
1304 p += 2;
1305 s = ntohs(*(uint16_t *) p);
1306 p += 2;
1307 if (s >= MAXSESSION)
1308 {
1309 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1310 STAT(tunnel_rx_errors);
1311 return;
1312 }
1313 if (t >= MAXTUNNEL)
1314 {
1315 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1316 STAT(tunnel_rx_errors);
1317 return;
1318 }
1319 if (*buf & 0x08)
1320 { // ns/nr
1321 ns = ntohs(*(uint16_t *) p);
1322 p += 2;
1323 nr = ntohs(*(uint16_t *) p);
1324 p += 2;
1325 }
1326 if (*buf & 0x02)
1327 { // offset
1328 uint16_t o = ntohs(*(uint16_t *) p);
1329 p += o + 2;
1330 }
1331 if ((p - buf) > l)
1332 {
1333 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1334 STAT(tunnel_rx_errors);
1335 return;
1336 }
1337 l -= (p - buf);
1338 if (*buf & 0x80)
1339 { // control
1340 uint16_t message = 0xFFFF; // message type
1341 uint8_t fatal = 0;
1342 uint8_t mandatorymessage = 0;
1343 uint8_t chap = 0; // if CHAP being used
1344 uint16_t asession = 0; // assigned session
1345 uint32_t amagic = 0; // magic number
1346 uint8_t aflags = 0; // flags from last LCF
1347 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1348 int requestchap = 0; // do we request PAP instead of original CHAP request?
1349 char called[MAXTEL] = ""; // called number
1350 char calling[MAXTEL] = ""; // calling number
1351
1352 if (!config->cluster_iam_master)
1353 {
1354 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1355 return;
1356 }
1357
1358 if ((*buf & 0xCA) != 0xC8)
1359 {
1360 LOG(1, s, t, "Bad control header %02X\n", *buf);
1361 STAT(tunnel_rx_errors);
1362 return;
1363 }
1364
1365 // check for duplicate tunnel open message
1366 if (!t && ns == 0)
1367 {
1368 int i;
1369
1370 //
1371 // Is this a duplicate of the first packet? (SCCRQ)
1372 //
1373 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1374 {
1375 if (tunnel[i].state != TUNNELOPENING ||
1376 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1377 tunnel[i].port != ntohs(addr->sin_port) )
1378 continue;
1379 t = i;
1380 LOG(3, s, t, "Duplicate SCCRQ?\n");
1381 break;
1382 }
1383 }
1384
1385 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1386 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1387
1388 // if no tunnel specified, assign one
1389 if (!t)
1390 {
1391 if (!(t = new_tunnel()))
1392 {
1393 LOG(1, 0, 0, "No more tunnels\n");
1394 STAT(tunnel_overflow);
1395 return;
1396 }
1397 tunnelclear(t);
1398 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1399 tunnel[t].port = ntohs(addr->sin_port);
1400 tunnel[t].window = 4; // default window
1401 STAT(tunnel_created);
1402 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1403 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1404 }
1405
1406 // If the 'ns' just received is not the 'nr' we're
1407 // expecting, just send an ack and drop it.
1408 //
1409 // if 'ns' is less, then we got a retransmitted packet.
1410 // if 'ns' is greater than missed a packet. Either way
1411 // we should ignore it.
1412 if (ns != tunnel[t].nr)
1413 {
1414 // is this the sequence we were expecting?
1415 STAT(tunnel_rx_errors);
1416 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1417 t, ns, tunnel[t].nr);
1418
1419 if (l) // Is this not a ZLB?
1420 controlnull(t);
1421 return;
1422 }
1423
1424 // This is used to time out old tunnels
1425 tunnel[t].lastrec = time_now;
1426
1427 // check sequence of this message
1428 {
1429 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1430 // some to clear maybe?
1431 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1432 {
1433 controlt *c = tunnel[t].controls;
1434 tunnel[t].controls = c->next;
1435 tunnel[t].controlc--;
1436 c->next = controlfree;
1437 controlfree = c;
1438 skip--;
1439 tunnel[t].try = 0; // we have progress
1440 }
1441
1442 // receiver advance (do here so quoted correctly in any sends below)
1443 if (l) tunnel[t].nr = (ns + 1);
1444 if (skip < 0) skip = 0;
1445 if (skip < tunnel[t].controlc)
1446 {
1447 // some control packets can now be sent that were previous stuck out of window
1448 int tosend = tunnel[t].window - skip;
1449 controlt *c = tunnel[t].controls;
1450 while (c && skip)
1451 {
1452 c = c->next;
1453 skip--;
1454 }
1455 while (c && tosend)
1456 {
1457 tunnel[t].try = 0; // first send
1458 tunnelsend(c->buf, c->length, t);
1459 c = c->next;
1460 tosend--;
1461 }
1462 }
1463 if (!tunnel[t].controlc)
1464 tunnel[t].retry = 0; // caught up
1465 }
1466 if (l)
1467 { // if not a null message
1468 // process AVPs
1469 while (l && !(fatal & 0x80))
1470 {
1471 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1472 uint8_t *b = p;
1473 uint8_t flags = *p;
1474 uint16_t mtype;
1475 p += n; // next
1476 if (l < n)
1477 {
1478 LOG(1, s, t, "Invalid length in AVP\n");
1479 STAT(tunnel_rx_errors);
1480 fatal = flags;
1481 return;
1482 }
1483 l -= n;
1484 if (flags & 0x40)
1485 {
1486 // handle hidden AVPs
1487 if (!*config->l2tpsecret)
1488 {
1489 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
1490 fatal = flags;
1491 continue;
1492 }
1493 if (!session[s].random_vector_length)
1494 {
1495 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
1496 fatal = flags;
1497 continue;
1498 }
1499 LOG(4, s, t, "Hidden AVP\n");
1500 // Unhide the AVP
1501 n = unhide_avp(b, t, s, n);
1502 if (n == 0)
1503 {
1504 fatal = flags;
1505 continue;
1506 }
1507 }
1508 if (*b & 0x3C)
1509 {
1510 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1511 fatal = flags;
1512 continue; // next
1513 }
1514 b += 2;
1515 if (*(uint16_t *) (b))
1516 {
1517 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1518 fatal = flags;
1519 continue; // next
1520 }
1521 b += 2;
1522 mtype = ntohs(*(uint16_t *) (b));
1523 b += 2;
1524 n -= 6;
1525
1526 LOG(4, s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1527 switch (mtype)
1528 {
1529 case 0: // message type
1530 message = ntohs(*(uint16_t *) b);
1531 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_types[message]);
1532 mandatorymessage = flags;
1533 break;
1534 case 1: // result code
1535 {
1536 uint16_t rescode = ntohs(*(uint16_t *) b);
1537 const char* resdesc = "(unknown)";
1538 if (message == 4)
1539 { /* StopCCN */
1540 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1541 resdesc = stopccn_result_codes[rescode];
1542 }
1543 else if (message == 14)
1544 { /* CDN */
1545 if (rescode <= MAX_CDN_RESULT_CODE)
1546 resdesc = cdn_result_codes[rescode];
1547 }
1548
1549 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
1550 if (n >= 4)
1551 {
1552 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
1553 const char* errdesc = "(unknown)";
1554 if (errcode <= MAX_ERROR_CODE)
1555 errdesc = error_codes[errcode];
1556 LOG(4, s, t, " Error Code %d: %s\n", errcode, errdesc);
1557 }
1558 if (n > 4)
1559 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
1560
1561 break;
1562 }
1563 break;
1564 case 2: // protocol version
1565 {
1566 version = ntohs(*(uint16_t *) (b));
1567 LOG(4, s, t, " Protocol version = %d\n", version);
1568 if (version && version != 0x0100)
1569 { // allow 0.0 and 1.0
1570 LOG(1, s, t, " Bad protocol version %04X\n", version);
1571 fatal = flags;
1572 continue; // next
1573 }
1574 }
1575 break;
1576 case 3: // framing capabilities
1577 // LOG(4, s, t, "Framing capabilities\n");
1578 break;
1579 case 4: // bearer capabilities
1580 // LOG(4, s, t, "Bearer capabilities\n");
1581 break;
1582 case 5: // tie breaker
1583 // We never open tunnels, so we don't care about tie breakers
1584 // LOG(4, s, t, "Tie breaker\n");
1585 continue;
1586 case 6: // firmware revision
1587 // LOG(4, s, t, "Firmware revision\n");
1588 break;
1589 case 7: // host name
1590 memset(tunnel[t].hostname, 0, 128);
1591 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1592 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1593 // TBA - to send to RADIUS
1594 break;
1595 case 8: // vendor name
1596 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1597 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1598 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1599 break;
1600 case 9: // assigned tunnel
1601 tunnel[t].far = ntohs(*(uint16_t *) (b));
1602 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1603 break;
1604 case 10: // rx window
1605 tunnel[t].window = ntohs(*(uint16_t *) (b));
1606 if (!tunnel[t].window)
1607 tunnel[t].window = 1; // window of 0 is silly
1608 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
1609 break;
1610 case 11: // Challenge
1611 {
1612 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
1613 build_chap_response(b, 2, n, &chapresponse);
1614 }
1615 break;
1616 case 13: // Response
1617 // Why did they send a response? We never challenge.
1618 LOG(2, s, t, " received unexpected challenge response\n");
1619 break;
1620
1621 case 14: // assigned session
1622 asession = session[s].far = ntohs(*(uint16_t *) (b));
1623 LOG(4, s, t, " assigned session = %d\n", asession);
1624 break;
1625 case 15: // call serial number
1626 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
1627 break;
1628 case 18: // bearer type
1629 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
1630 // TBA - for RADIUS
1631 break;
1632 case 19: // framing type
1633 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
1634 // TBA
1635 break;
1636 case 21: // called number
1637 memset(called, 0, MAXTEL);
1638 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1639 LOG(4, s, t, " Called <%s>\n", called);
1640 break;
1641 case 22: // calling number
1642 memset(calling, 0, MAXTEL);
1643 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1644 LOG(4, s, t, " Calling <%s>\n", calling);
1645 break;
1646 case 23: // subtype
1647 break;
1648 case 24: // tx connect speed
1649 if (n == 4)
1650 {
1651 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
1652 }
1653 else
1654 {
1655 // AS5300s send connect speed as a string
1656 char tmp[30] = {0};
1657 memcpy(tmp, b, (n >= 30) ? 30 : n);
1658 session[s].tx_connect_speed = atol(tmp);
1659 }
1660 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
1661 break;
1662 case 38: // rx connect speed
1663 if (n == 4)
1664 {
1665 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
1666 }
1667 else
1668 {
1669 // AS5300s send connect speed as a string
1670 char tmp[30] = {0};
1671 memcpy(tmp, b, (n >= 30) ? 30 : n);
1672 session[s].rx_connect_speed = atol(tmp);
1673 }
1674 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
1675 break;
1676 case 25: // Physical Channel ID
1677 {
1678 uint32_t tmp = ntohl(*(uint32_t *) b);
1679 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
1680 break;
1681 }
1682 case 29: // Proxy Authentication Type
1683 {
1684 uint16_t authtype = ntohs(*(uint16_t *)b);
1685 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", authtype, authtypes[authtype]);
1686 requestchap = (authtype == 2);
1687 break;
1688 }
1689 case 30: // Proxy Authentication Name
1690 {
1691 char authname[64] = {0};
1692 memcpy(authname, b, (n > 63) ? 63 : n);
1693 LOG(4, s, t, " Proxy Auth Name (%s)\n",
1694 authname);
1695 break;
1696 }
1697 case 31: // Proxy Authentication Challenge
1698 {
1699 memcpy(radius[session[s].radius].auth, b, 16);
1700 LOG(4, s, t, " Proxy Auth Challenge\n");
1701 break;
1702 }
1703 case 32: // Proxy Authentication ID
1704 {
1705 uint16_t authid = ntohs(*(uint16_t *)(b));
1706 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
1707 if (session[s].radius)
1708 radius[session[s].radius].id = authid;
1709 break;
1710 }
1711 case 33: // Proxy Authentication Response
1712 {
1713 char authresp[64] = {0};
1714 memcpy(authresp, b, (n > 63) ? 63 : n);
1715 LOG(4, s, t, " Proxy Auth Response\n");
1716 break;
1717 }
1718 case 27: // last send lcp
1719 { // find magic number
1720 uint8_t *p = b, *e = p + n;
1721 while (p + 1 < e && p[1] && p + p[1] <= e)
1722 {
1723 if (*p == 5 && p[1] == 6) // Magic-Number
1724 amagic = ntohl(*(uint32_t *) (p + 2));
1725 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
1726 chap = 1;
1727 else if (*p == 7) // Protocol-Field-Compression
1728 aflags |= SESSIONPFC;
1729 else if (*p == 8) // Address-and-Control-Field-Compression
1730 aflags |= SESSIONACFC;
1731 p += p[1];
1732 }
1733 }
1734 break;
1735 case 28: // last recv lcp confreq
1736 break;
1737 case 26: // Initial Received LCP CONFREQ
1738 break;
1739 case 39: // seq required - we control it as an LNS anyway...
1740 break;
1741 case 36: // Random Vector
1742 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
1743 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1744 memcpy(session[s].random_vector, b, n);
1745 session[s].random_vector_length = n;
1746 break;
1747 default:
1748 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
1749 fatal = flags;
1750 continue; // next
1751 }
1752 }
1753 // process message
1754 if (fatal & 0x80)
1755 tunnelshutdown(t, "Unknown Mandatory AVP");
1756 else
1757 switch (message)
1758 {
1759 case 1: // SCCRQ - Start Control Connection Request
1760 {
1761 controlt *c = controlnew(2); // sending SCCRP
1762 control16(c, 2, version, 1); // protocol version
1763 control32(c, 3, 3, 1); // framing
1764 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1765 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1766 control16(c, 9, t, 1); // assigned tunnel
1767 controladd(c, t, s); // send the resply
1768 }
1769 tunnel[t].state = TUNNELOPENING;
1770 break;
1771 case 2: // SCCRP
1772 tunnel[t].state = TUNNELOPEN;
1773 break;
1774 case 3: // SCCN
1775 tunnel[t].state = TUNNELOPEN;
1776 controlnull(t); // ack
1777 break;
1778 case 4: // StopCCN
1779 controlnull(t); // ack
1780 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1781 tunnelkill(t, "Stopped"); // Immediately force everything dead
1782 break;
1783 case 6: // HELLO
1784 controlnull(t); // simply ACK
1785 break;
1786 case 7: // OCRQ
1787 // TBA
1788 break;
1789 case 8: // OCRO
1790 // TBA
1791 break;
1792 case 9: // OCCN
1793 // TBA
1794 break;
1795 case 10: // ICRQ
1796 if (!sessionfree)
1797 {
1798 STAT(session_overflow);
1799 tunnelshutdown(t, "No free sessions");
1800 }
1801 else
1802 {
1803 uint16_t r;
1804 controlt *c;
1805
1806 s = sessionfree;
1807 sessionfree = session[s].next;
1808 memset(&session[s], 0, sizeof(session[s]));
1809
1810 if (s > config->cluster_highest_sessionid)
1811 config->cluster_highest_sessionid = s;
1812
1813 // make a RADIUS session
1814 if (!(r = radiusnew(s)))
1815 {
1816 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
1817 sessionkill(s, "no free RADIUS sesions");
1818 return;
1819 }
1820
1821 c = controlnew(11); // sending ICRP
1822 session[s].id = sessionid++;
1823 session[s].opened = time(NULL);
1824 session[s].tunnel = t;
1825 session[s].far = asession;
1826 session[s].last_packet = time_now;
1827 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1828 control16(c, 14, s, 1); // assigned session
1829 controladd(c, t, s); // send the reply
1830 {
1831 // Generate a random challenge
1832 int n;
1833 for (n = 0; n < 15; n++)
1834 radius[r].auth[n] = rand();
1835 }
1836 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1837 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1838 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1839 STAT(session_created);
1840 }
1841 break;
1842 case 11: // ICRP
1843 // TBA
1844 break;
1845 case 12: // ICCN
1846 if (amagic == 0) amagic = time_now;
1847 session[s].magic = amagic; // set magic number
1848 session[s].l2tp_flags = aflags; // set flags received
1849 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
1850 controlnull(t); // ack
1851 // In CHAP state, request PAP instead
1852 if (requestchap)
1853 initlcp(t, s);
1854 break;
1855 case 14: // CDN
1856 controlnull(t); // ack
1857 sessionshutdown(s, "Closed (Received CDN)");
1858 break;
1859 case 0xFFFF:
1860 LOG(1, s, t, "Missing message type\n");
1861 break;
1862 default:
1863 STAT(tunnel_rx_errors);
1864 if (mandatorymessage & 0x80)
1865 tunnelshutdown(t, "Unknown message");
1866 else
1867 LOG(1, s, t, "Unknown message type %d\n", message);
1868 break;
1869 }
1870 if (chapresponse) free(chapresponse);
1871 cluster_send_tunnel(t);
1872 }
1873 else
1874 {
1875 LOG(4, s, t, " Got a ZLB ack\n");
1876 }
1877 }
1878 else
1879 { // data
1880 uint16_t prot;
1881
1882 LOG_HEX(5, "Receive Tunnel Data", p, l);
1883 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1884 { // HDLC address header, discard
1885 p += 2;
1886 l -= 2;
1887 }
1888 if (l < 2)
1889 {
1890 LOG(1, s, t, "Short ppp length %d\n", l);
1891 STAT(tunnel_rx_errors);
1892 return;
1893 }
1894 if (*p & 1)
1895 {
1896 prot = *p++;
1897 l--;
1898 }
1899 else
1900 {
1901 prot = ntohs(*(uint16_t *) p);
1902 p += 2;
1903 l -= 2;
1904 }
1905
1906 if (s && !session[s].tunnel) // Is something wrong??
1907 {
1908 if (!config->cluster_iam_master)
1909 {
1910 // Pass it off to the master to deal with..
1911 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1912 return;
1913 }
1914
1915
1916 LOG(1, s, t, "UDP packet contains session %d but no session[%d].tunnel "
1917 "exists (LAC said tunnel = %d). Dropping packet.\n", s, s, t);
1918
1919 STAT(tunnel_rx_errors);
1920 return;
1921 }
1922
1923 if (prot == PPPPAP)
1924 {
1925 session[s].last_packet = time_now;
1926 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1927 processpap(t, s, p, l);
1928 }
1929 else if (prot == PPPCHAP)
1930 {
1931 session[s].last_packet = time_now;
1932 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1933 processchap(t, s, p, l);
1934 }
1935 else if (prot == PPPLCP)
1936 {
1937 session[s].last_packet = time_now;
1938 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1939 processlcp(t, s, p, l);
1940 }
1941 else if (prot == PPPIPCP)
1942 {
1943 session[s].last_packet = time_now;
1944 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1945 processipcp(t, s, p, l);
1946 }
1947 else if (prot == PPPCCP)
1948 {
1949 session[s].last_packet = time_now;
1950 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1951 processccp(t, s, p, l);
1952 }
1953 else if (prot == PPPIP)
1954 {
1955 if (session[s].die)
1956 {
1957 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
1958 return; // closing session, PPP not processed
1959 }
1960
1961 session[s].last_packet = time_now;
1962 if (session[s].walled_garden && !config->cluster_iam_master)
1963 {
1964 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1965 return;
1966 }
1967
1968 processipin(t, s, p, l);
1969 }
1970 else
1971 {
1972 STAT(tunnel_rx_errors);
1973 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
1974 }
1975 }
1976 }
1977
1978 // read and process packet on tun
1979 static void processtun(uint8_t * buf, int len)
1980 {
1981 LOG_HEX(5, "Receive TUN Data", buf, len);
1982 STAT(tun_rx_packets);
1983 INC_STAT(tun_rx_bytes, len);
1984
1985 CSTAT(call_processtun);
1986
1987 eth_rx_pkt++;
1988 eth_rx += len;
1989 if (len < 22)
1990 {
1991 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
1992 STAT(tun_rx_errors);
1993 return;
1994 }
1995
1996 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IP
1997 processipout(buf, len);
1998 // Else discard.
1999 }
2000
2001 //
2002 // Maximum number of actions to complete.
2003 // This is to avoid sending out too many packets
2004 // at once.
2005 #define MAX_ACTIONS 500
2006
2007 static int regular_cleanups(void)
2008 {
2009 static sessionidt s = 0; // Next session to check for actions on.
2010 tunnelidt t;
2011 int count=0,i;
2012 uint16_t r;
2013 static clockt next_acct = 0;
2014 static clockt next_shut_acct = 0;
2015 int a;
2016
2017 LOG(3, 0, 0, "Begin regular cleanup\n");
2018
2019 for (r = 1; r < MAXRADIUS; r++)
2020 {
2021 if (!radius[r].state)
2022 continue;
2023 if (radius[r].retry)
2024 {
2025 if (radius[r].retry <= TIME)
2026 radiusretry(r);
2027 } else
2028 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2029 }
2030 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
2031 {
2032 // check for expired tunnels
2033 if (tunnel[t].die && tunnel[t].die <= TIME)
2034 {
2035 STAT(tunnel_timeout);
2036 tunnelkill(t, "Expired");
2037 continue;
2038 }
2039 // check for message resend
2040 if (tunnel[t].retry && tunnel[t].controlc)
2041 {
2042 // resend pending messages as timeout on reply
2043 if (tunnel[t].retry <= TIME)
2044 {
2045 controlt *c = tunnel[t].controls;
2046 uint8_t w = tunnel[t].window;
2047 tunnel[t].try++; // another try
2048 if (tunnel[t].try > 5)
2049 tunnelkill(t, "Timeout on control message"); // game over
2050 else
2051 while (c && w--)
2052 {
2053 tunnelsend(c->buf, c->length, t);
2054 c = c->next;
2055 }
2056 }
2057 }
2058 // Send hello
2059 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2060 {
2061 controlt *c = controlnew(6); // sending HELLO
2062 controladd(c, t, 0); // send the message
2063 LOG(3, 0, t, "Sending HELLO message\n");
2064 }
2065
2066 // Check for tunnel changes requested from the CLI
2067 if ((a = cli_tunnel_actions[t].action))
2068 {
2069 cli_tunnel_actions[t].action = 0;
2070 if (a & CLI_TUN_KILL)
2071 {
2072 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2073 tunnelshutdown(t, "Requested by administrator");
2074 }
2075 }
2076
2077 }
2078
2079 count = 0;
2080 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2081 {
2082 s++;
2083 if (s > config->cluster_highest_sessionid)
2084 s = 1;
2085
2086 if (!session[s].tunnel) // Session isn't in use
2087 continue;
2088
2089 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2090 {
2091 // IPCP has not completed yet. Resend
2092 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2093 sendipcp(session[s].tunnel, s);
2094 }
2095
2096 // check for expired sessions
2097 if (session[s].die && session[s].die <= TIME)
2098 {
2099 sessionkill(s, "Expired");
2100 if (++count >= MAX_ACTIONS) break;
2101 continue;
2102 }
2103
2104 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2105 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2106 {
2107 sessionshutdown(s, "No response to LCP ECHO requests");
2108 STAT(session_timeout);
2109 if (++count >= MAX_ACTIONS) break;
2110 continue;
2111 }
2112
2113 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2114 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2115 {
2116 uint8_t b[MAXCONTROL] = {0};
2117
2118 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2119 if (!q) continue;
2120
2121 *q = EchoReq;
2122 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2123 *(uint16_t *)(q + 2) = htons(8); // Length
2124 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2125
2126 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2127 (int)(time_now - session[s].last_packet));
2128 tunnelsend(b, 24, session[s].tunnel); // send it
2129 if (++count >= MAX_ACTIONS) break;
2130 }
2131
2132 // Check for actions requested from the CLI
2133 if ((a = cli_session_actions[s].action))
2134 {
2135 int send = 0;
2136
2137 cli_session_actions[s].action = 0;
2138 if (a & CLI_SESS_KILL)
2139 {
2140 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2141 sessionshutdown(s, "Requested by administrator");
2142 a = 0; // dead, no need to check for other actions
2143 }
2144
2145 if (a & CLI_SESS_NOSNOOP)
2146 {
2147 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2148 session[s].snoop_ip = 0;
2149 session[s].snoop_port = 0;
2150 send++;
2151 }
2152 else if (a & CLI_SESS_SNOOP)
2153 {
2154 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2155 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2156 cli_session_actions[s].snoop_port);
2157
2158 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2159 session[s].snoop_port = cli_session_actions[s].snoop_port;
2160 send++;
2161 }
2162
2163 if (a & CLI_SESS_NOTHROTTLE)
2164 {
2165 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2166 throttle_session(s, 0, 0);
2167 send++;
2168 }
2169 else if (a & CLI_SESS_THROTTLE)
2170 {
2171 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2172 cli_session_actions[s].throttle_in,
2173 cli_session_actions[s].throttle_out);
2174
2175 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2176 send++;
2177 }
2178
2179 if (a & CLI_SESS_NOFILTER)
2180 {
2181 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2182 filter_session(s, 0, 0);
2183 send++;
2184 }
2185 else if (a & CLI_SESS_FILTER)
2186 {
2187 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2188 cli_session_actions[s].filter_in,
2189 cli_session_actions[s].filter_out);
2190
2191 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2192 send++;
2193 }
2194
2195 if (send)
2196 cluster_send_session(s);
2197
2198 if (++count >= MAX_ACTIONS) break;
2199 }
2200 }
2201
2202 if (*config->accounting_dir)
2203 {
2204 if (next_acct <= TIME)
2205 {
2206 // Dump accounting data
2207 next_acct = TIME + ACCT_TIME;
2208 next_shut_acct = TIME + ACCT_SHUT_TIME;
2209 dump_acct_info(1);
2210 }
2211 else if (next_shut_acct <= TIME)
2212 {
2213 // Dump accounting data for shutdown sessions
2214 next_shut_acct = TIME + ACCT_SHUT_TIME;
2215 if (shut_acct_n)
2216 dump_acct_info(0);
2217 }
2218 }
2219
2220 if (count >= MAX_ACTIONS)
2221 return 1; // Didn't finish!
2222
2223 LOG(3, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2224 return 0;
2225 }
2226
2227
2228 //
2229 // Are we in the middle of a tunnel update, or radius
2230 // requests??
2231 //
2232 static int still_busy(void)
2233 {
2234 int i;
2235 static clockt last_talked = 0;
2236 static clockt start_busy_wait = 0;
2237 if (start_busy_wait == 0)
2238 start_busy_wait = TIME;
2239
2240 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2241 {
2242 if (!tunnel[i].controlc)
2243 continue;
2244
2245 if (last_talked != TIME)
2246 {
2247 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2248 last_talked = TIME;
2249 }
2250 return 1;
2251 }
2252
2253 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2254 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2255 {
2256 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2257 return 0;
2258 }
2259
2260 for (i = 1; i < MAXRADIUS; i++)
2261 {
2262 if (radius[i].state == RADIUSNULL)
2263 continue;
2264 if (radius[i].state == RADIUSWAIT)
2265 continue;
2266
2267 if (last_talked != TIME)
2268 {
2269 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2270 last_talked = TIME;
2271 }
2272 return 1;
2273 }
2274
2275 return 0;
2276 }
2277
2278 static fd_set readset;
2279 static int readset_n = 0;
2280
2281 // main loop - gets packets on tun or udp and processes them
2282 static void mainloop(void)
2283 {
2284 int i;
2285 uint8_t buf[65536];
2286 struct timeval to;
2287 clockt next_cluster_ping = 0; // send initial ping immediately
2288 time_t next_clean = time_now + config->cleanup_interval;
2289
2290 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2291 udpfd, tunfd, cluster_sockfd, controlfd);
2292
2293 FD_ZERO(&readset);
2294 FD_SET(udpfd, &readset);
2295 FD_SET(tunfd, &readset);
2296 FD_SET(controlfd, &readset);
2297 FD_SET(clifd, &readset);
2298 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2299 readset_n = udpfd;
2300 if (tunfd > readset_n) readset_n = tunfd;
2301 if (controlfd > readset_n) readset_n = controlfd;
2302 if (clifd > readset_n) readset_n = clifd;
2303 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2304
2305 while (!main_quit || still_busy())
2306 {
2307 fd_set r;
2308 int n = readset_n;
2309 #ifdef BGP
2310 fd_set w;
2311 int bgp_set[BGP_NUM_PEERS];
2312 #endif /* BGP */
2313
2314 if (config->reload_config)
2315 {
2316 // Update the config state based on config settings
2317 update_config();
2318 }
2319
2320 memcpy(&r, &readset, sizeof(fd_set));
2321 to.tv_sec = 0;
2322 to.tv_usec = 100000; // 1/10th of a second.
2323
2324 #ifdef BGP
2325 FD_ZERO(&w);
2326 for (i = 0; i < BGP_NUM_PEERS; i++)
2327 {
2328 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2329 if (bgp_set[i] & 1)
2330 {
2331 FD_SET(bgp_peers[i].sock, &r);
2332 if (bgp_peers[i].sock > n)
2333 n = bgp_peers[i].sock;
2334 }
2335
2336 if (bgp_set[i] & 2)
2337 {
2338 FD_SET(bgp_peers[i].sock, &w);
2339 if (bgp_peers[i].sock > n)
2340 n = bgp_peers[i].sock;
2341 }
2342 }
2343
2344 n = select(n + 1, &r, &w, 0, &to);
2345 #else /* BGP */
2346 n = select(n + 1, &r, 0, 0, &to);
2347 #endif /* BGP */
2348
2349 STAT(select_called);
2350
2351 TIME = now();
2352 if (n < 0)
2353 {
2354 if (errno == EINTR ||
2355 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2356 continue;
2357
2358 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2359 main_quit++;
2360 break;
2361 }
2362 else if (n)
2363 {
2364 struct sockaddr_in addr;
2365 int alen, c, s;
2366 int udp_pkts = 0;
2367 int tun_pkts = 0;
2368 int cluster_pkts = 0;
2369
2370 INC_STAT(select_ready, n);
2371
2372 // nsctl commands
2373 if (FD_ISSET(controlfd, &r))
2374 {
2375 alen = sizeof(addr);
2376 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2377 STAT(select_processed);
2378 n--;
2379 }
2380
2381 // RADIUS responses
2382 if (config->cluster_iam_master)
2383 {
2384 for (i = 0; i < config->num_radfds; i++)
2385 {
2386 if (FD_ISSET(radfds[i], &r))
2387 {
2388 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2389 STAT(select_processed);
2390 n--;
2391 }
2392 }
2393 }
2394
2395 // CLI connections
2396 if (FD_ISSET(clifd, &r))
2397 {
2398 int cli;
2399
2400 alen = sizeof(addr);
2401 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
2402 {
2403 cli_do(cli);
2404 close(cli);
2405 }
2406 else
2407 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
2408
2409 STAT(select_processed);
2410 n--;
2411 }
2412
2413 #ifdef BGP
2414 for (i = 0; i < BGP_NUM_PEERS; i++)
2415 {
2416 int isr = bgp_set[i] ? !!FD_ISSET(bgp_peers[i].sock, &r) : 0;
2417 int isw = bgp_set[i] ? !!FD_ISSET(bgp_peers[i].sock, &w) : 0;
2418 bgp_process(&bgp_peers[i], isr, isw);
2419 if (isr || isw)
2420 {
2421 INC_STAT(select_processed, isr + isw);
2422 n -= (isr + isw);
2423 }
2424 }
2425 #endif /* BGP */
2426
2427 for (c = 0; n && c < config->multi_read_count; c++)
2428 {
2429 // L2TP
2430 if (FD_ISSET(udpfd, &r))
2431 {
2432 alen = sizeof(addr);
2433 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2434 {
2435 processudp(buf, s, &addr);
2436 STAT(select_processed);
2437 udp_pkts++;
2438 }
2439 else
2440 {
2441 FD_CLR(udpfd, &r);
2442 n--;
2443 }
2444 }
2445
2446 // incoming IP
2447 if (FD_ISSET(tunfd, &r))
2448 {
2449 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
2450 {
2451 processtun(buf, s);
2452 STAT(select_processed);
2453 tun_pkts++;
2454 }
2455 else
2456 {
2457 FD_CLR(tunfd, &r);
2458 n--;
2459 }
2460 }
2461
2462 // cluster
2463 if (FD_ISSET(cluster_sockfd, &r))
2464 {
2465 alen = sizeof(addr);
2466 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
2467 {
2468 processcluster(buf, s, addr.sin_addr.s_addr);
2469 STAT(select_processed);
2470 cluster_pkts++;
2471 }
2472 else
2473 {
2474 FD_CLR(cluster_sockfd, &r);
2475 n--;
2476 }
2477 }
2478 }
2479
2480 if (c >= config->multi_read_count)
2481 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
2482 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
2483 }
2484
2485 // Runs on every machine (master and slaves).
2486 if (cluster_sockfd && next_cluster_ping <= TIME)
2487 {
2488 // Check to see which of the cluster is still alive..
2489
2490 cluster_send_ping(basetime); // Only does anything if we're a slave
2491 cluster_check_master(); // ditto.
2492
2493 cluster_heartbeat(); // Only does anything if we're a master.
2494 cluster_check_slaves(); // ditto.
2495
2496 master_update_counts(); // If we're a slave, send our byte counters to our master.
2497
2498 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2499 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2500 else
2501 next_cluster_ping = TIME + config->cluster_hb_interval;
2502 }
2503
2504 // Run token bucket filtering queue..
2505 // Only run it every 1/10th of a second.
2506 // Runs on all machines both master and slave.
2507 {
2508 static clockt last_run = 0;
2509 if (last_run != TIME)
2510 {
2511 last_run = TIME;
2512 tbf_run_timer();
2513 }
2514 }
2515
2516 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2517 * something to read, else under load this will never actually run....
2518 *
2519 */
2520 if (config->cluster_iam_master && next_clean <= time_now)
2521 {
2522 if (regular_cleanups())
2523 {
2524 // Did it finish?
2525 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2526 }
2527 else
2528 {
2529 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2530 }
2531 }
2532 }
2533
2534 // Are we the master and shutting down??
2535 if (config->cluster_iam_master)
2536 cluster_heartbeat(); // Flush any queued changes..
2537
2538 // Ok. Notify everyone we're shutting down. If we're
2539 // the master, this will force an election.
2540 cluster_send_ping(0);
2541
2542 //
2543 // Important!!! We MUST not process any packets past this point!
2544 }
2545
2546 static void stripdomain(char *host)
2547 {
2548 char *p;
2549
2550 if ((p = strchr(host, '.')))
2551 {
2552 char *domain = 0;
2553 char _domain[1024];
2554
2555 // strip off domain
2556 FILE *resolv = fopen("/etc/resolv.conf", "r");
2557 if (resolv)
2558 {
2559 char buf[1024];
2560 char *b;
2561
2562 while (fgets(buf, sizeof(buf), resolv))
2563 {
2564 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
2565 continue;
2566
2567 if (!isspace(buf[6]))
2568 continue;
2569
2570 b = buf + 7;
2571 while (isspace(*b)) b++;
2572
2573 if (*b)
2574 {
2575 char *d = b;
2576 while (*b && !isspace(*b)) b++;
2577 *b = 0;
2578 if (buf[0] == 'd') // domain is canonical
2579 {
2580 domain = d;
2581 break;
2582 }
2583
2584 // first search line
2585 if (!domain)
2586 {
2587 // hold, may be subsequent domain line
2588 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
2589 domain = _domain;
2590 }
2591 }
2592 }
2593
2594 fclose(resolv);
2595 }
2596
2597 if (domain)
2598 {
2599 int hl = strlen(host);
2600 int dl = strlen(domain);
2601 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
2602 host[hl -dl - 1] = 0;
2603 }
2604 else
2605 {
2606 *p = 0; // everything after first dot
2607 }
2608 }
2609 }
2610
2611 // Init data structures
2612 static void initdata(int optdebug, char *optconfig)
2613 {
2614 int i;
2615
2616 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
2617 {
2618 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
2619 exit(1);
2620 }
2621 if (!(config = shared_malloc(sizeof(configt))))
2622 {
2623 LOG(0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
2624 exit(1);
2625 }
2626 memset(config, 0, sizeof(configt));
2627 time(&config->start_time);
2628 strncpy(config->config_file, optconfig, strlen(optconfig));
2629 config->debug = optdebug;
2630 config->num_tbfs = MAXTBFS;
2631 config->rl_rate = 28; // 28kbps
2632
2633 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
2634 {
2635 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
2636 exit(1);
2637 }
2638 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
2639 {
2640 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
2641 exit(1);
2642 }
2643
2644 if (!(sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)))
2645 {
2646 LOG(0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
2647 exit(1);
2648 }
2649
2650 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
2651 {
2652 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
2653 exit(1);
2654 }
2655
2656 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
2657 {
2658 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
2659 exit(1);
2660 }
2661
2662 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
2663 {
2664 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
2665 exit(1);
2666 }
2667 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
2668
2669 #ifdef RINGBUFFER
2670 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
2671 {
2672 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
2673 exit(1);
2674 }
2675 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2676 #endif
2677
2678 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
2679 {
2680 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
2681 exit(1);
2682 }
2683 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2684
2685 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
2686 {
2687 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
2688 exit(1);
2689 }
2690 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2691
2692 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2693 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2694 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2695 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2696
2697 // Put all the sessions on the free list marked as undefined.
2698 for (i = 1; i < MAXSESSION - 1; i++)
2699 {
2700 session[i].next = i + 1;
2701 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2702 }
2703 session[MAXSESSION - 1].next = 0;
2704 sessionfree = 1;
2705
2706 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2707 for (i = 1; i < MAXTUNNEL- 1; i++)
2708 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2709
2710 if (!*hostname)
2711 {
2712 // Grab my hostname unless it's been specified
2713 gethostname(hostname, sizeof(hostname));
2714 stripdomain(hostname);
2715 }
2716
2717 _statistics->start_time = _statistics->last_reset = time(NULL);
2718
2719 #ifdef BGP
2720 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
2721 {
2722 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
2723 exit(1);
2724 }
2725 #endif /* BGP */
2726 }
2727
2728 static int assign_ip_address(sessionidt s)
2729 {
2730 uint32_t i;
2731 int best = -1;
2732 time_t best_time = time_now;
2733 char *u = session[s].user;
2734 char reuse = 0;
2735
2736
2737 CSTAT(call_assign_ip_address);
2738
2739 for (i = 1; i < ip_pool_size; i++)
2740 {
2741 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2742 continue;
2743
2744 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2745 {
2746 best = i;
2747 reuse = 1;
2748 break;
2749 }
2750
2751 if (ip_address_pool[i].last < best_time)
2752 {
2753 best = i;
2754 if (!(best_time = ip_address_pool[i].last))
2755 break; // never used, grab this one
2756 }
2757 }
2758
2759 if (best < 0)
2760 {
2761 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2762 return 0;
2763 }
2764
2765 session[s].ip = ip_address_pool[best].address;
2766 session[s].ip_pool_index = best;
2767 ip_address_pool[best].assigned = 1;
2768 ip_address_pool[best].last = time_now;
2769 ip_address_pool[best].session = s;
2770 if (session[s].walled_garden)
2771 /* Don't track addresses of users in walled garden (note: this
2772 means that their address isn't "sticky" even if they get
2773 un-gardened). */
2774 ip_address_pool[best].user[0] = 0;
2775 else
2776 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2777
2778 STAT(ip_allocated);
2779 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
2780 reuse ? "Reusing" : "Allocating", best);
2781
2782 return 1;
2783 }
2784
2785 static void free_ip_address(sessionidt s)
2786 {
2787 int i = session[s].ip_pool_index;
2788
2789
2790 CSTAT(call_free_ip_address);
2791
2792 if (!session[s].ip)
2793 return; // what the?
2794
2795 if (i < 0) // Is this actually part of the ip pool?
2796 i = 0;
2797
2798 STAT(ip_freed);
2799 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2800 session[s].ip = 0;
2801 ip_address_pool[i].assigned = 0;
2802 ip_address_pool[i].session = 0;
2803 ip_address_pool[i].last = time_now;
2804 }
2805
2806 //
2807 // Fsck the address pool against the session table.
2808 // Normally only called when we become a master.
2809 //
2810 // This isn't perfect: We aren't keep tracking of which
2811 // users used to have an IP address.
2812 //
2813 void rebuild_address_pool(void)
2814 {
2815 int i;
2816
2817 //
2818 // Zero the IP pool allocation, and build
2819 // a map from IP address to pool index.
2820 for (i = 1; i < MAXIPPOOL; ++i)
2821 {
2822 ip_address_pool[i].assigned = 0;
2823 ip_address_pool[i].session = 0;
2824 if (!ip_address_pool[i].address)
2825 continue;
2826
2827 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2828 }
2829
2830 for (i = 0; i < MAXSESSION; ++i)
2831 {
2832 int ipid;
2833 if (!session[i].ip || !session[i].tunnel)
2834 continue;
2835 ipid = - lookup_ipmap(htonl(session[i].ip));
2836
2837 if (session[i].ip_pool_index < 0)
2838 {
2839 // Not allocated out of the pool.
2840 if (ipid < 1) // Not found in the pool either? good.
2841 continue;
2842
2843 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2844 i, fmtaddr(session[i].ip, 0), ipid);
2845
2846 // Fall through and process it as part of the pool.
2847 }
2848
2849
2850 if (ipid > MAXIPPOOL || ipid < 0)
2851 {
2852 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2853 ipid = -1;
2854 session[i].ip_pool_index = ipid;
2855 continue;
2856 }
2857
2858 ip_address_pool[ipid].assigned = 1;
2859 ip_address_pool[ipid].session = i;
2860 ip_address_pool[ipid].last = time_now;
2861 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2862 session[i].ip_pool_index = ipid;
2863 cache_ipmap(session[i].ip, i); // Fix the ip map.
2864 }
2865 }
2866
2867 //
2868 // Fix the address pool to match a changed session.
2869 // (usually when the master sends us an update).
2870 static void fix_address_pool(int sid)
2871 {
2872 int ipid;
2873
2874 ipid = session[sid].ip_pool_index;
2875
2876 if (ipid > ip_pool_size)
2877 return; // Ignore it. rebuild_address_pool will fix it up.
2878
2879 if (ip_address_pool[ipid].address != session[sid].ip)
2880 return; // Just ignore it. rebuild_address_pool will take care of it.
2881
2882 ip_address_pool[ipid].assigned = 1;
2883 ip_address_pool[ipid].session = sid;
2884 ip_address_pool[ipid].last = time_now;
2885 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2886 }
2887
2888 //
2889 // Add a block of addresses to the IP pool to hand out.
2890 //
2891 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
2892 {
2893 int i;
2894 if (mask == 0)
2895 mask = 0xffffffff; // Host route only.
2896
2897 addr &= mask;
2898
2899 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2900 return ;
2901
2902 for (i = addr ;(i & mask) == addr; ++i)
2903 {
2904 if ((i & 0xff) == 0 || (i&0xff) == 255)
2905 continue; // Skip 0 and broadcast addresses.
2906
2907 ip_address_pool[ip_pool_size].address = i;
2908 ip_address_pool[ip_pool_size].assigned = 0;
2909 ++ip_pool_size;
2910 if (ip_pool_size >= MAXIPPOOL)
2911 {
2912 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
2913 return;
2914 }
2915 }
2916 }
2917
2918 // Initialize the IP address pool
2919 static void initippool()
2920 {
2921 FILE *f;
2922 char *p;
2923 char buf[4096];
2924 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2925
2926 if (!(f = fopen(IPPOOLFILE, "r")))
2927 {
2928 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2929 exit(1);
2930 }
2931
2932 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2933 {
2934 char *pool = buf;
2935 buf[4095] = 0; // Force it to be zero terminated/
2936
2937 if (*buf == '#' || *buf == '\n')
2938 continue; // Skip comments / blank lines
2939 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2940 if ((p = (char *)strchr(buf, ':')))
2941 {
2942 in_addr_t src;
2943 *p = '\0';
2944 src = inet_addr(buf);
2945 if (src == INADDR_NONE)
2946 {
2947 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
2948 exit(1);
2949 }
2950 // This entry is for a specific IP only
2951 if (src != config->bind_address)
2952 continue;
2953 *p = ':';
2954 pool = p+1;
2955 }
2956 if ((p = (char *)strchr(pool, '/')))
2957 {
2958 // It's a range
2959 int numbits = 0;
2960 in_addr_t start = 0, mask = 0;
2961
2962 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
2963 *p++ = 0;
2964 if (!*p || !(numbits = atoi(p)))
2965 {
2966 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
2967 continue;
2968 }
2969 start = ntohl(inet_addr(pool));
2970 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
2971
2972 // Add a static route for this pool
2973 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
2974 fmtaddr(htonl(start), 0), 32 + mask);
2975
2976 routeset(0, start, mask, 0, 1);
2977
2978 add_to_ip_pool(start, mask);
2979 }
2980 else
2981 {
2982 // It's a single ip address
2983 add_to_ip_pool(inet_addr(pool), 0);
2984 }
2985 }
2986 fclose(f);
2987 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2988 }
2989
2990 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
2991 {
2992 struct sockaddr_in snoop_addr = {0};
2993 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2994 return;
2995
2996 snoop_addr.sin_family = AF_INET;
2997 snoop_addr.sin_addr.s_addr = destination;
2998 snoop_addr.sin_port = ntohs(port);
2999
3000 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3001 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3002 htons(snoop_addr.sin_port));
3003
3004 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3005 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3006
3007 STAT(packets_snooped);
3008 }
3009
3010 static int dump_session(FILE **f, sessiont *s)
3011 {
3012 if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
3013 return 1;
3014
3015 if (!*f)
3016 {
3017 char filename[1024];
3018 char timestr[64];
3019 time_t now = time(NULL);
3020
3021 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3022 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3023
3024 if (!(*f = fopen(filename, "w")))
3025 {
3026 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3027 return 0;
3028 }
3029
3030 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3031 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3032 "# host: %s\n"
3033 "# time: %ld\n"
3034 "# uptime: %ld\n"
3035 "# format: username ip qos uptxoctets downrxoctets\n",
3036 hostname,
3037 now,
3038 now - basetime);
3039 }
3040
3041 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3042 fprintf(*f, "%s %s %d %u %u\n",
3043 s->user, // username
3044 fmtaddr(htonl(s->ip), 0), // ip
3045 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3046 (uint32_t) s->cin, // uptxoctets
3047 (uint32_t) s->cout); // downrxoctets
3048
3049 s->pin = s->cin = 0;
3050 s->pout = s->cout = 0;
3051
3052 return 1;
3053 }
3054
3055 static void dump_acct_info(int all)
3056 {
3057 int i;
3058 FILE *f = NULL;
3059
3060
3061 CSTAT(call_dump_acct_info);
3062
3063 if (shut_acct_n)
3064 {
3065 for (i = 0; i < shut_acct_n; i++)
3066 dump_session(&f, &shut_acct[i]);
3067
3068 shut_acct_n = 0;
3069 }
3070
3071 if (all)
3072 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3073 dump_session(&f, &session[i]);
3074
3075 if (f)
3076 fclose(f);
3077 }
3078
3079 // Main program
3080 int main(int argc, char *argv[])
3081 {
3082 int i;
3083 int optdebug = 0;
3084 char *optconfig = CONFIGFILE;
3085
3086 time(&basetime); // start clock
3087
3088 // scan args
3089 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3090 {
3091 switch (i)
3092 {
3093 case 'd':
3094 if (fork()) exit(0);
3095 setsid();
3096 freopen("/dev/null", "r", stdin);
3097 freopen("/dev/null", "w", stdout);
3098 freopen("/dev/null", "w", stderr);
3099 break;
3100 case 'v':
3101 optdebug++;
3102 break;
3103 case 'c':
3104 optconfig = optarg;
3105 break;
3106 case 'h':
3107 snprintf(hostname, sizeof(hostname), "%s", optarg);
3108 break;
3109 default:
3110 printf("Args are:\n"
3111 "\t-d\t\tDetach from terminal\n"
3112 "\t-c <file>\tConfig file\n"
3113 "\t-h <hostname>\tForce hostname\n"
3114 "\t-v\t\tDebug\n");
3115
3116 return (0);
3117 break;
3118 }
3119 }
3120
3121 // Start the timer routine off
3122 time(&time_now);
3123 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3124 signal(SIGALRM, sigalrm_handler);
3125 siginterrupt(SIGALRM, 0);
3126
3127 initplugins();
3128 initdata(optdebug, optconfig);
3129
3130 init_cli(hostname);
3131 read_config_file();
3132 init_tbf(config->num_tbfs);
3133
3134 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3135 LOG(0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
3136 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3137 {
3138 struct rlimit rlim;
3139 rlim.rlim_cur = RLIM_INFINITY;
3140 rlim.rlim_max = RLIM_INFINITY;
3141 // Remove the maximum core size
3142 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3143 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3144
3145 // Make core dumps go to /tmp
3146 chdir("/tmp");
3147 }
3148
3149 if (config->scheduler_fifo)
3150 {
3151 int ret;
3152 struct sched_param params = {0};
3153 params.sched_priority = 1;
3154
3155 if (get_nprocs() < 2)
3156 {
3157 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3158 config->scheduler_fifo = 0;
3159 }
3160 else
3161 {
3162 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3163 {
3164 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3165 }
3166 else
3167 {
3168 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3169 config->scheduler_fifo = 0;
3170 }
3171 }
3172 }
3173
3174 /* Set up the cluster communications port. */
3175 if (cluster_init() < 0)
3176 exit(1);
3177
3178 #ifdef BGP
3179 signal(SIGPIPE, SIG_IGN);
3180 bgp_setup(config->as_number);
3181 bgp_add_route(config->bind_address, 0xffffffff);
3182 for (i = 0; i < BGP_NUM_PEERS; i++)
3183 {
3184 if (config->neighbour[i].name[0])
3185 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3186 config->neighbour[i].as, config->neighbour[i].keepalive,
3187 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3188 }
3189 #endif /* BGP */
3190
3191 inittun();
3192 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3193
3194 initudp();
3195 initrad();
3196 initippool();
3197
3198 read_state();
3199
3200 signal(SIGHUP, sighup_handler);
3201 signal(SIGTERM, sigterm_handler);
3202 signal(SIGINT, sigterm_handler);
3203 signal(SIGQUIT, sigquit_handler);
3204 signal(SIGCHLD, sigchild_handler);
3205
3206 // Prevent us from getting paged out
3207 if (config->lock_pages)
3208 {
3209 if (!mlockall(MCL_CURRENT))
3210 LOG(1, 0, 0, "Locking pages into memory\n");
3211 else
3212 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3213 }
3214
3215 alarm(1);
3216
3217 // Drop privileges here
3218 if (config->target_uid > 0 && geteuid() == 0)
3219 setuid(config->target_uid);
3220
3221 mainloop();
3222
3223 #ifdef BGP
3224 /* try to shut BGP down cleanly; with luck the sockets will be
3225 writable since we're out of the select */
3226 for (i = 0; i < BGP_NUM_PEERS; i++)
3227 if (bgp_peers[i].state == Established)
3228 bgp_stop(&bgp_peers[i]);
3229 #endif /* BGP */
3230
3231 /* remove plugins (so cleanup code gets run) */
3232 plugins_done();
3233
3234 // Remove the PID file if we wrote it
3235 if (config->wrote_pid && *config->pid_file == '/')
3236 unlink(config->pid_file);
3237
3238 /* kill CLI children */
3239 signal(SIGTERM, SIG_IGN);
3240 kill(0, SIGTERM);
3241 return 0;
3242 }
3243
3244 static void sighup_handler(int sig)
3245 {
3246 if (log_stream && log_stream != stderr)
3247 {
3248 fclose(log_stream);
3249 log_stream = NULL;
3250 }
3251
3252 read_config_file();
3253 }
3254
3255 static void sigalrm_handler(int sig)
3256 {
3257 // Log current traffic stats
3258
3259 snprintf(config->bandwidth, sizeof(config->bandwidth),
3260 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3261 (udp_rx / 1024.0 / 1024.0 * 8),
3262 (eth_tx / 1024.0 / 1024.0 * 8),
3263 (eth_rx / 1024.0 / 1024.0 * 8),
3264 (udp_tx / 1024.0 / 1024.0 * 8),
3265 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3266 udp_rx_pkt, eth_rx_pkt);
3267
3268 udp_tx = udp_rx = 0;
3269 udp_rx_pkt = eth_rx_pkt = 0;
3270 eth_tx = eth_rx = 0;
3271
3272 if (config->dump_speed)
3273 printf("%s\n", config->bandwidth);
3274
3275 // Update the internal time counter
3276 time(&time_now);
3277 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3278 alarm(1);
3279
3280 {
3281 // Run timer hooks
3282 struct param_timer p = { time_now };
3283 run_plugins(PLUGIN_TIMER, &p);
3284 }
3285
3286 }
3287
3288 static void sigterm_handler(int sig)
3289 {
3290 LOG(1, 0, 0, "Shutting down cleanly\n");
3291 if (config->save_state)
3292 dump_state();
3293
3294 main_quit++;
3295 }
3296
3297 static void sigquit_handler(int sig)
3298 {
3299 int i;
3300
3301 LOG(1, 0, 0, "Shutting down without saving sessions\n");
3302
3303 if (config->cluster_iam_master)
3304 {
3305 for (i = 1; i < MAXSESSION; i++)
3306 {
3307 if (session[i].opened)
3308 sessionkill(i, "L2TPNS Closing");
3309 }
3310 for (i = 1; i < MAXTUNNEL; i++)
3311 {
3312 if (tunnel[i].ip || tunnel[i].state)
3313 tunnelshutdown(i, "L2TPNS Closing");
3314 }
3315 }
3316
3317 main_quit++;
3318 }
3319
3320 static void sigchild_handler(int sig)
3321 {
3322 while (waitpid(-1, NULL, WNOHANG) > 0)
3323 ;
3324 }
3325
3326 static void read_state()
3327 {
3328 struct stat sb;
3329 int i;
3330 ippoolt itmp;
3331 FILE *f;
3332 char magic[sizeof(DUMP_MAGIC) - 1];
3333 uint32_t buf[2];
3334
3335 if (!config->save_state)
3336 {
3337 unlink(STATEFILE);
3338 return ;
3339 }
3340
3341 if (stat(STATEFILE, &sb) < 0)
3342 {
3343 unlink(STATEFILE);
3344 return ;
3345 }
3346
3347 if (sb.st_mtime < (time(NULL) - 60))
3348 {
3349 LOG(0, 0, 0, "State file is too old to read, ignoring\n");
3350 unlink(STATEFILE);
3351 return ;
3352 }
3353
3354 f = fopen(STATEFILE, "r");
3355 unlink(STATEFILE);
3356
3357 if (!f)
3358 {
3359 LOG(0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3360 exit(1);
3361 }
3362
3363 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3364 {
3365 LOG(0, 0, 0, "Bad state file magic\n");
3366 exit(1);
3367 }
3368
3369 LOG(1, 0, 0, "Reading state information\n");
3370 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3371 {
3372 LOG(0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3373 exit(1);
3374 }
3375
3376 if (buf[0] > ip_pool_size)
3377 {
3378 LOG(0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3379 exit(1);
3380 }
3381
3382 LOG(2, 0, 0, "Loading %u ip addresses\n", buf[0]);
3383 for (i = 0; i < buf[0]; i++)
3384 {
3385 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3386 {
3387 LOG(0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3388 exit(1);
3389 }
3390
3391 if (itmp.address != ip_address_pool[i].address)
3392 {
3393 LOG(0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3394 exit(1);
3395 }
3396
3397 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3398 }
3399
3400 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3401 {
3402 LOG(0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3403 exit(1);
3404 }
3405
3406 LOG(2, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3407 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3408 {
3409 LOG(0, 0, 0, "Error reading tunnel data from state file\n");
3410 exit(1);
3411 }
3412
3413 for (i = 0; i < MAXTUNNEL; i++)
3414 {
3415 tunnel[i].controlc = 0;
3416 tunnel[i].controls = NULL;
3417 tunnel[i].controle = NULL;
3418 if (*tunnel[i].hostname)
3419 LOG(3, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3420 }
3421
3422 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3423 {
3424 LOG(0, 0, 0, "Error/mismatch reading session header from state file\n");
3425 exit(1);
3426 }
3427
3428 LOG(2, 0, 0, "Loading %u sessions\n", MAXSESSION);
3429 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3430 {
3431 LOG(0, 0, 0, "Error reading session data from state file\n");
3432 exit(1);
3433 }
3434
3435 for (i = 0; i < MAXSESSION; i++)
3436 {
3437 session[i].tbf_in = 0;
3438 session[i].tbf_out = 0;
3439 if (session[i].opened)
3440 {
3441 LOG(2, i, 0, "Loaded active session for user %s\n", session[i].user);
3442 if (session[i].ip)
3443 sessionsetup(session[i].tunnel, i);
3444 }
3445 }
3446
3447 fclose(f);
3448 LOG(0, 0, 0, "Loaded saved state information\n");
3449 }
3450
3451 static void dump_state()
3452 {
3453 FILE *f;
3454 uint32_t buf[2];
3455
3456 if (!config->save_state)
3457 return;
3458
3459 do
3460 {
3461 if (!(f = fopen(STATEFILE, "w")))
3462 break;
3463
3464 LOG(1, 0, 0, "Dumping state information\n");
3465
3466 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
3467 break;
3468
3469 LOG(2, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3470 buf[0] = ip_pool_size;
3471 buf[1] = sizeof(ippoolt);
3472 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3473 break;
3474 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
3475 break;
3476
3477 LOG(2, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3478 buf[0] = MAXTUNNEL;
3479 buf[1] = sizeof(tunnelt);
3480 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3481 break;
3482 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3483 break;
3484
3485 LOG(2, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3486 buf[0] = MAXSESSION;
3487 buf[1] = sizeof(sessiont);
3488 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3489 break;
3490 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3491 break;
3492
3493 if (fclose(f) == 0)
3494 return ; // OK
3495 }
3496 while (0);
3497
3498 LOG(0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3499 unlink(STATEFILE);
3500 }
3501
3502 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
3503 {
3504 MD5_CTX ctx;
3505 *challenge_response = NULL;
3506
3507 if (!*config->l2tpsecret)
3508 {
3509 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3510 return;
3511 }
3512
3513 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
3514
3515 *challenge_response = (char *)calloc(17, 1);
3516
3517 MD5Init(&ctx);
3518 MD5Update(&ctx, &id, 1);
3519 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3520 MD5Update(&ctx, challenge, challenge_length);
3521 MD5Final(*challenge_response, &ctx);
3522
3523 return;
3524 }
3525
3526 static int facility_value(char *name)
3527 {
3528 int i;
3529 for (i = 0; facilitynames[i].c_name; i++)
3530 {
3531 if (strcmp(facilitynames[i].c_name, name) == 0)
3532 return facilitynames[i].c_val;
3533 }
3534 return 0;
3535 }
3536
3537 static void update_config()
3538 {
3539 int i;
3540 static int timeout = 0;
3541 static int interval = 0;
3542
3543 // Update logging
3544 closelog();
3545 syslog_log = 0;
3546 if (log_stream)
3547 {
3548 fclose(log_stream);
3549 log_stream = NULL;
3550 }
3551 if (*config->log_filename)
3552 {
3553 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3554 {
3555 char *p = config->log_filename + 7;
3556 if (*p)
3557 {
3558 openlog("l2tpns", LOG_PID, facility_value(p));
3559 syslog_log = 1;
3560 }
3561 }
3562 else if (strchr(config->log_filename, '/') == config->log_filename)
3563 {
3564 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3565 {
3566 fseek(log_stream, 0, SEEK_END);
3567 setbuf(log_stream, NULL);
3568 }
3569 else
3570 {
3571 log_stream = stderr;
3572 setbuf(log_stream, NULL);
3573 }
3574 }
3575 }
3576 else
3577 {
3578 log_stream = stderr;
3579 setbuf(log_stream, NULL);
3580 }
3581
3582
3583 // Update radius
3584 config->numradiusservers = 0;
3585 for (i = 0; i < MAXRADSERVER; i++)
3586 if (config->radiusserver[i])
3587 {
3588 config->numradiusservers++;
3589 // Set radius port: if not set, take the port from the
3590 // first radius server. For the first radius server,
3591 // take the #defined default value from l2tpns.h
3592
3593 // test twice, In case someone works with
3594 // a secondary radius server without defining
3595 // a primary one, this will work even then.
3596 if (i>0 && !config->radiusport[i])
3597 config->radiusport[i] = config->radiusport[i-1];
3598 if (!config->radiusport[i])
3599 config->radiusport[i] = RADPORT;
3600 }
3601
3602 if (!config->numradiusservers)
3603 LOG(0, 0, 0, "No RADIUS servers defined!\n");
3604
3605 config->num_radfds = 2 << RADIUS_SHIFT;
3606
3607 // Update plugins
3608 for (i = 0; i < MAXPLUGINS; i++)
3609 {
3610 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3611 continue;
3612
3613 if (*config->plugins[i])
3614 {
3615 // Plugin added
3616 add_plugin(config->plugins[i]);
3617 }
3618 else if (*config->old_plugins[i])
3619 {
3620 // Plugin removed
3621 remove_plugin(config->old_plugins[i]);
3622 }
3623 }
3624 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3625 if (!config->cleanup_interval) config->cleanup_interval = 10;
3626 if (!config->multi_read_count) config->multi_read_count = 10;
3627 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3628 if (!*config->cluster_interface)
3629 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3630
3631 if (!config->cluster_hb_interval)
3632 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3633
3634 if (!config->cluster_hb_timeout)
3635 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3636
3637 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3638 {
3639 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3640 // late, ensure we're sufficiently larger than that
3641 int t = 4 * config->cluster_hb_interval + 11;
3642
3643 if (config->cluster_hb_timeout < t)
3644 {
3645 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3646 config->cluster_hb_timeout = t;
3647 }
3648
3649 // Push timing changes to the slaves immediately if we're the master
3650 if (config->cluster_iam_master)
3651 cluster_heartbeat();
3652
3653 interval = config->cluster_hb_interval;
3654 timeout = config->cluster_hb_timeout;
3655 }
3656
3657 // Write PID file
3658 if (*config->pid_file == '/' && !config->wrote_pid)
3659 {
3660 FILE *f;
3661 if ((f = fopen(config->pid_file, "w")))
3662 {
3663 fprintf(f, "%d\n", getpid());
3664 fclose(f);
3665 config->wrote_pid = 1;
3666 }
3667 else
3668 {
3669 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3670 }
3671 }
3672
3673 config->reload_config = 0;
3674 }
3675
3676 static void read_config_file()
3677 {
3678 FILE *f;
3679
3680 if (!config->config_file) return;
3681 if (!(f = fopen(config->config_file, "r")))
3682 {
3683 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3684 return;
3685 }
3686
3687 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
3688 cli_do_file(f);
3689 LOG(3, 0, 0, "Done reading config file\n");
3690 fclose(f);
3691 update_config();
3692 }
3693
3694 int sessionsetup(tunnelidt t, sessionidt s)
3695 {
3696 // A session now exists, set it up
3697 in_addr_t ip;
3698 char *user;
3699 sessionidt i;
3700 int r;
3701
3702 CSTAT(call_sessionsetup);
3703
3704 LOG(3, s, t, "Doing session setup for session\n");
3705
3706 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3707 {
3708 assign_ip_address(s);
3709 if (!session[s].ip)
3710 {
3711 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3712 sessionshutdown(s, "No IP addresses available");
3713 return 0;
3714 }
3715 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
3716 fmtaddr(htonl(session[s].ip), 0));
3717 }
3718
3719
3720 // Make sure this is right
3721 session[s].tunnel = t;
3722
3723 // zap old sessions with same IP and/or username
3724 // Don't kill gardened sessions - doing so leads to a DoS
3725 // from someone who doesn't need to know the password
3726 {
3727 ip = session[s].ip;
3728 user = session[s].user;
3729 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3730 {
3731 if (i == s) continue;
3732 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3733 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3734 sessionkill(i, "Duplicate session for users");
3735 }
3736 }
3737
3738 {
3739 int routed = 0;
3740
3741 // Add the route for this session.
3742 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3743 {
3744 if ((session[s].ip & session[s].route[r].mask) ==
3745 (session[s].route[r].ip & session[s].route[r].mask))
3746 routed++;
3747
3748 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
3749 }
3750
3751 // Static IPs need to be routed if not already
3752 // convered by a Framed-Route. Anything else is part
3753 // of the IP address pool and is already routed, it
3754 // just needs to be added to the IP cache.
3755 if (session[s].ip_pool_index == -1) // static ip
3756 {
3757 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
3758 }
3759 else
3760 cache_ipmap(session[s].ip, s);
3761 }
3762
3763 if (!session[s].unique_id)
3764 {
3765 // did this session just finish radius?
3766 LOG(3, s, t, "Sending initial IPCP to client\n");
3767 sendipcp(t, s);
3768 session[s].unique_id = ++last_id;
3769 }
3770
3771 // Run the plugin's against this new session.
3772 {
3773 struct param_new_session data = { &tunnel[t], &session[s] };
3774 run_plugins(PLUGIN_NEW_SESSION, &data);
3775 }
3776
3777 // Allocate TBFs if throttled
3778 if (session[s].throttle_in || session[s].throttle_out)
3779 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
3780
3781 session[s].last_packet = time_now;
3782
3783 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
3784 fmtaddr(htonl(session[s].ip), 0),
3785 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
3786
3787 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3788
3789 return 1; // RADIUS OK and IP allocated, done...
3790 }
3791
3792 //
3793 // This session just got dropped on us by the master or something.
3794 // Make sure our tables up up to date...
3795 //
3796 int load_session(sessionidt s, sessiont *new)
3797 {
3798 int i;
3799 int newip = 0;
3800
3801 // Sanity checks.
3802 if (new->ip_pool_index >= MAXIPPOOL ||
3803 new->tunnel >= MAXTUNNEL)
3804 {
3805 LOG(0, s, 0, "Strange session update received!\n");
3806 // FIXME! What to do here?
3807 return 0;
3808 }
3809
3810 //
3811 // Ok. All sanity checks passed. Now we're committed to
3812 // loading the new session.
3813 //
3814
3815 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3816
3817 // See if routes/ip cache need updating
3818 if (new->ip != session[s].ip)
3819 newip++;
3820
3821 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3822 if (new->route[i].ip != session[s].route[i].ip ||
3823 new->route[i].mask != session[s].route[i].mask)
3824 newip++;
3825
3826 // needs update
3827 if (newip)
3828 {
3829 int routed = 0;
3830
3831 // remove old routes...
3832 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3833 {
3834 if ((session[s].ip & session[s].route[i].mask) ==
3835 (session[s].route[i].ip & session[s].route[i].mask))
3836 routed++;
3837
3838 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
3839 }
3840
3841 // ...ip
3842 if (session[s].ip)
3843 {
3844 if (session[s].ip_pool_index == -1) // static IP
3845 {
3846 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
3847 }
3848 else // It's part of the IP pool, remove it manually.
3849 uncache_ipmap(session[s].ip);
3850 }
3851
3852 routed = 0;
3853
3854 // add new routes...
3855 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
3856 {
3857 if ((new->ip & new->route[i].mask) ==
3858 (new->route[i].ip & new->route[i].mask))
3859 routed++;
3860
3861 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
3862 }
3863
3864 // ...ip
3865 if (new->ip)
3866 {
3867 // If there's a new one, add it.
3868 if (new->ip_pool_index == -1)
3869 {
3870 if (!routed) routeset(s, new->ip, 0, 0, 1);
3871 }
3872 else
3873 cache_ipmap(new->ip, s);
3874 }
3875 }
3876
3877 // check filters
3878 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
3879 {
3880 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
3881 new->filter_in = 0;
3882 }
3883
3884 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
3885 {
3886 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
3887 new->filter_out = 0;
3888 }
3889
3890 if (new->filter_in != session[s].filter_in)
3891 {
3892 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
3893 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
3894 }
3895
3896 if (new->filter_out != session[s].filter_out)
3897 {
3898 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
3899 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
3900 }
3901
3902 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3903 // for walking the sessions to forward byte counts to the master.
3904 config->cluster_highest_sessionid = s;
3905
3906 // TEMP: old session struct used a uint32_t to define the throttle
3907 // speed for both up/down, new uses a uint16_t for each. Deal with
3908 // sessions from an old master for migration.
3909 if (new->throttle_out == 0 && new->tbf_out)
3910 new->throttle_out = new->throttle_in;
3911
3912 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3913
3914 // Do fixups into address pool.
3915 if (new->ip_pool_index != -1)
3916 fix_address_pool(s);
3917
3918 return 1;
3919 }
3920
3921 static void initplugins()
3922 {
3923 int i;
3924
3925 loaded_plugins = ll_init();
3926 // Initialize the plugins to nothing
3927 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3928 plugins[i] = ll_init();
3929 }
3930
3931 static void *open_plugin(char *plugin_name, int load)
3932 {
3933 char path[256] = "";
3934
3935 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3936 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3937 return dlopen(path, RTLD_NOW);
3938 }
3939
3940 // plugin callback to get a config value
3941 static void *getconfig(char *key, enum config_typet type)
3942 {
3943 int i;
3944
3945 for (i = 0; config_values[i].key; i++)
3946 {
3947 if (!strcmp(config_values[i].key, key))
3948 {
3949 if (config_values[i].type == type)
3950 return ((void *) config) + config_values[i].offset;
3951
3952 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
3953 key, type, config_values[i].type);
3954
3955 return 0;
3956 }
3957 }
3958
3959 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
3960 return 0;
3961 }
3962
3963 static int add_plugin(char *plugin_name)
3964 {
3965 static struct pluginfuncs funcs = {
3966 _log,
3967 _log_hex,
3968 fmtaddr,
3969 sessionbyuser,
3970 sessiontbysessionidt,
3971 sessionidtbysessiont,
3972 radiusnew,
3973 radiussend,
3974 getconfig,
3975 sessionkill,
3976 throttle_session,
3977 cluster_send_session,
3978 };
3979
3980 void *p = open_plugin(plugin_name, 1);
3981 int (*initfunc)(struct pluginfuncs *);
3982 int i;
3983
3984 if (!p)
3985 {
3986 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
3987 return -1;
3988 }
3989
3990 if (ll_contains(loaded_plugins, p))
3991 {
3992 dlclose(p);
3993 return 0; // already loaded
3994 }
3995
3996 {
3997 int *v = dlsym(p, "plugin_api_version");
3998 if (!v || *v != PLUGIN_API_VERSION)
3999 {
4000 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4001 dlclose(p);
4002 return -1;
4003 }
4004 }
4005
4006 if ((initfunc = dlsym(p, "plugin_init")))
4007 {
4008 if (!initfunc(&funcs))
4009 {
4010 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4011 dlclose(p);
4012 return -1;
4013 }
4014 }
4015
4016 ll_push(loaded_plugins, p);
4017
4018 for (i = 0; i < max_plugin_functions; i++)
4019 {
4020 void *x;
4021 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4022 {
4023 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4024 ll_push(plugins[i], x);
4025 }
4026 }
4027
4028 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4029 return 1;
4030 }
4031
4032 static void run_plugin_done(void *plugin)
4033 {
4034 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4035
4036 if (donefunc)
4037 donefunc();
4038 }
4039
4040 static int remove_plugin(char *plugin_name)
4041 {
4042 void *p = open_plugin(plugin_name, 0);
4043 int loaded = 0;
4044
4045 if (!p)
4046 return -1;
4047
4048 if (ll_contains(loaded_plugins, p))
4049 {
4050 int i;
4051 for (i = 0; i < max_plugin_functions; i++)
4052 {
4053 void *x;
4054 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4055 ll_delete(plugins[i], x);
4056 }
4057
4058 ll_delete(loaded_plugins, p);
4059 run_plugin_done(p);
4060 loaded = 1;
4061 }
4062
4063 dlclose(p);
4064 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4065 return loaded;
4066 }
4067
4068 int run_plugins(int plugin_type, void *data)
4069 {
4070 int (*func)(void *data);
4071
4072 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4073 return PLUGIN_RET_ERROR;
4074
4075 ll_reset(plugins[plugin_type]);
4076 while ((func = ll_next(plugins[plugin_type])))
4077 {
4078 int r = func(data);
4079
4080 if (r != PLUGIN_RET_OK)
4081 return r; // stop here
4082 }
4083
4084 return PLUGIN_RET_OK;
4085 }
4086
4087 static void plugins_done()
4088 {
4089 void *p;
4090
4091 ll_reset(loaded_plugins);
4092 while ((p = ll_next(loaded_plugins)))
4093 run_plugin_done(p);
4094 }
4095
4096 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4097 {
4098 struct nsctl request;
4099 struct nsctl response;
4100 int type = unpack_control(&request, buf, len);
4101 int r;
4102 void *p;
4103
4104 if (log_stream && config->debug >= 4)
4105 {
4106 if (type < 0)
4107 {
4108 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4109 fmtaddr(addr->sin_addr.s_addr, 0), type);
4110 }
4111 else
4112 {
4113 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4114 dump_control(&request, log_stream);
4115 }
4116 }
4117
4118 switch (type)
4119 {
4120 case NSCTL_REQ_LOAD:
4121 if (request.argc != 1)
4122 {
4123 response.type = NSCTL_RES_ERR;
4124 response.argc = 1;
4125 response.argv[0] = "name of plugin required";
4126 }
4127 else if ((r = add_plugin(request.argv[0])) < 1)
4128 {
4129 response.type = NSCTL_RES_ERR;
4130 response.argc = 1;
4131 response.argv[0] = !r
4132 ? "plugin already loaded"
4133 : "error loading plugin";
4134 }
4135 else
4136 {
4137 response.type = NSCTL_RES_OK;
4138 response.argc = 0;
4139 }
4140
4141 break;
4142
4143 case NSCTL_REQ_UNLOAD:
4144 if (request.argc != 1)
4145 {
4146 response.type = NSCTL_RES_ERR;
4147 response.argc = 1;
4148 response.argv[0] = "name of plugin required";
4149 }
4150 else if ((r = remove_plugin(request.argv[0])) < 1)
4151 {
4152 response.type = NSCTL_RES_ERR;
4153 response.argc = 1;
4154 response.argv[0] = !r
4155 ? "plugin not loaded"
4156 : "plugin not found";
4157 }
4158 else
4159 {
4160 response.type = NSCTL_RES_OK;
4161 response.argc = 0;
4162 }
4163
4164 break;
4165
4166 case NSCTL_REQ_HELP:
4167 response.type = NSCTL_RES_OK;
4168 response.argc = 0;
4169
4170 ll_reset(loaded_plugins);
4171 while ((p = ll_next(loaded_plugins)))
4172 {
4173 char **help = dlsym(p, "plugin_control_help");
4174 while (response.argc < 0xff && help && *help)
4175 response.argv[response.argc++] = *help++;
4176 }
4177
4178 break;
4179
4180 case NSCTL_REQ_CONTROL:
4181 {
4182 struct param_control param = {
4183 config->cluster_iam_master,
4184 request.argc,
4185 request.argv,
4186 0,
4187 NULL,
4188 };
4189
4190 int r = run_plugins(PLUGIN_CONTROL, &param);
4191
4192 if (r == PLUGIN_RET_ERROR)
4193 {
4194 response.type = NSCTL_RES_ERR;
4195 response.argc = 1;
4196 response.argv[0] = param.additional
4197 ? param.additional
4198 : "error returned by plugin";
4199 }
4200 else if (r == PLUGIN_RET_NOTMASTER)
4201 {
4202 static char msg[] = "must be run on master: 000.000.000.000";
4203
4204 response.type = NSCTL_RES_ERR;
4205 response.argc = 1;
4206 if (config->cluster_master_address)
4207 {
4208 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4209 response.argv[0] = msg;
4210 }
4211 else
4212 {
4213 response.argv[0] = "must be run on master: none elected";
4214 }
4215 }
4216 else if (!(param.response & NSCTL_RESPONSE))
4217 {
4218 response.type = NSCTL_RES_ERR;
4219 response.argc = 1;
4220 response.argv[0] = param.response
4221 ? "unrecognised response value from plugin"
4222 : "unhandled action";
4223 }
4224 else
4225 {
4226 response.type = param.response;
4227 response.argc = 0;
4228 if (param.additional)
4229 {
4230 response.argc = 1;
4231 response.argv[0] = param.additional;
4232 }
4233 }
4234 }
4235
4236 break;
4237
4238 default:
4239 response.type = NSCTL_RES_ERR;
4240 response.argc = 1;
4241 response.argv[0] = "error unpacking control packet";
4242 }
4243
4244 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4245 if (!buf)
4246 {
4247 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4248 return;
4249 }
4250
4251 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4252 if (r > 0)
4253 {
4254 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4255 if (log_stream && config->debug >= 4)
4256 {
4257 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4258 dump_control(&response, log_stream);
4259 }
4260 }
4261 else
4262 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4263 fmtaddr(addr->sin_addr.s_addr, 0), r);
4264
4265 free(buf);
4266 }
4267
4268 static tunnelidt new_tunnel()
4269 {
4270 tunnelidt i;
4271 for (i = 1; i < MAXTUNNEL; i++)
4272 {
4273 if (tunnel[i].state == TUNNELFREE)
4274 {
4275 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4276 if (i > config->cluster_highest_tunnelid)
4277 config->cluster_highest_tunnelid = i;
4278 return i;
4279 }
4280 }
4281 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4282 return 0;
4283 }
4284
4285 //
4286 // We're becoming the master. Do any required setup..
4287 //
4288 // This is principally telling all the plugins that we're
4289 // now a master, and telling them about all the sessions
4290 // that are active too..
4291 //
4292 void become_master(void)
4293 {
4294 int s, i;
4295 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4296
4297 // running a bunch of iptables commands is slow and can cause
4298 // the master to drop tunnels on takeover--kludge around the
4299 // problem by forking for the moment (note: race)
4300 if (!fork_and_close())
4301 {
4302 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4303 {
4304 if (!session[s].tunnel) // Not an in-use session.
4305 continue;
4306
4307 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4308 }
4309 exit(0);
4310 }
4311
4312 // add radius fds
4313 for (i = 0; i < config->num_radfds; i++)
4314 {
4315 FD_SET(radfds[i], &readset);
4316 if (radfds[i] > readset_n)
4317 readset_n = radfds[i];
4318 }
4319 }
4320
4321 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4322 {
4323 int s, i;
4324 int count = 0;
4325 int buckets[64];
4326
4327 if (CLI_HELP_REQUESTED)
4328 return CLI_HELP_NO_ARGS;
4329
4330 time(&time_now);
4331 for (i = 0; i < 64;++i) buckets[i] = 0;
4332
4333 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4334 {
4335 int idle;
4336 if (!session[s].tunnel)
4337 continue;
4338
4339 idle = time_now - session[s].last_packet;
4340 idle /= 5 ; // In multiples of 5 seconds.
4341 if (idle < 0)
4342 idle = 0;
4343 if (idle > 63)
4344 idle = 63;
4345
4346 ++count;
4347 ++buckets[idle];
4348 }
4349
4350 for (i = 0; i < 63; ++i)
4351 {
4352 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4353 }
4354 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4355 cli_print(cli, "%d total sessions open.", count);
4356 return CLI_OK;
4357 }
4358
4359 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4360 {
4361 int s, i;
4362 int count = 0;
4363 int buckets[64];
4364
4365 if (CLI_HELP_REQUESTED)
4366 return CLI_HELP_NO_ARGS;
4367
4368 time(&time_now);
4369 for (i = 0; i < 64;++i) buckets[i] = 0;
4370
4371 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4372 {
4373 int open = 0, d;
4374 if (!session[s].tunnel)
4375 continue;
4376
4377 d = time_now - session[s].opened;
4378 if (d < 0)
4379 d = 0;
4380 while (d > 1 && open < 32)
4381 {
4382 ++open;
4383 d >>= 1; // half.
4384 }
4385 ++count;
4386 ++buckets[open];
4387 }
4388
4389 s = 1;
4390 for (i = 0; i < 30; ++i)
4391 {
4392 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4393 s <<= 1;
4394 }
4395 cli_print(cli, "%d total sessions open.", count);
4396 return CLI_OK;
4397 }
4398
4399 /* Unhide an avp.
4400 *
4401 * This unencodes the AVP using the L2TP CHAP secret and the
4402 * previously stored random vector. It replaces the hidden data with
4403 * the cleartext data and returns the length of the cleartext data
4404 * (including the AVP "header" of 6 bytes).
4405 *
4406 * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
4407 */
4408 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
4409 {
4410 MD5_CTX ctx;
4411 uint8_t *cursor;
4412 uint8_t digest[16];
4413 uint8_t working_vector[16];
4414 uint16_t hidden_length;
4415 uint8_t type[2];
4416 size_t done, todo;
4417 uint8_t *output;
4418
4419 // Find the AVP type.
4420 type[0] = *(avp + 4);
4421 type[1] = *(avp + 5);
4422
4423 // Line up with the hidden data
4424 cursor = output = avp + 6;
4425
4426 // Compute initial pad
4427 MD5Init(&ctx);
4428 MD5Update(&ctx, type, 2);
4429 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4430 MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
4431 MD5Final(digest, &ctx);
4432
4433 // Get hidden length
4434 hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
4435
4436 // Keep these for later use
4437 working_vector[0] = *cursor;
4438 working_vector[1] = *(cursor + 1);
4439 cursor += 2;
4440
4441 if (hidden_length > length - 8)
4442 {
4443 LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
4444 return 0;
4445 }
4446
4447 /* Decrypt remainder */
4448 done = 2;
4449 todo = hidden_length;
4450 while (todo)
4451 {
4452 working_vector[done] = *cursor;
4453 *output = digest[done] ^ *cursor;
4454 ++output;
4455 ++cursor;
4456 --todo;
4457 ++done;
4458 if (done == 16 && todo)
4459 {
4460 // Compute new digest
4461 done = 0;
4462 MD5Init(&ctx);
4463 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4464 MD5Update(&ctx, &working_vector, 16);
4465 MD5Final(digest, &ctx);
4466 }
4467 }
4468
4469 return hidden_length + 6;
4470 }
4471
4472 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
4473 {
4474 switch (p->op)
4475 {
4476 case FILTER_PORT_OP_EQ: return port == p->port;
4477 case FILTER_PORT_OP_NEQ: return port != p->port;
4478 case FILTER_PORT_OP_GT: return port > p->port;
4479 case FILTER_PORT_OP_LT: return port < p->port;
4480 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
4481 }
4482
4483 return 0;
4484 }
4485
4486 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
4487 {
4488 switch (op)
4489 {
4490 case FILTER_FLAG_OP_ANY:
4491 return (flags & sflags) || (~flags & cflags);
4492
4493 case FILTER_FLAG_OP_ALL:
4494 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
4495
4496 case FILTER_FLAG_OP_EST:
4497 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
4498 }
4499
4500 return 0;
4501 }
4502
4503 int ip_filter(uint8_t *buf, int len, uint8_t filter)
4504 {
4505 uint16_t frag_offset;
4506 uint8_t proto;
4507 in_addr_t src_ip;
4508 in_addr_t dst_ip;
4509 uint16_t src_port = 0;
4510 uint16_t dst_port = 0;
4511 uint8_t flags = 0;
4512 ip_filter_rulet *rule;
4513
4514 if (len < 20) // up to end of destination address
4515 return 0;
4516
4517 if ((*buf >> 4) != 4) // IPv4
4518 return 0;
4519
4520 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
4521 proto = buf[9];
4522 src_ip = *(in_addr_t *) (buf + 12);
4523 dst_ip = *(in_addr_t *) (buf + 16);
4524
4525 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
4526 {
4527 int l = (buf[0] & 0xf) * 4; // length of IP header
4528 if (len < l + 4) // ports
4529 return 0;
4530
4531 src_port = ntohs(*(uint16_t *) (buf + l));
4532 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
4533 if (proto == IPPROTO_TCP)
4534 {
4535 if (len < l + 14) // flags
4536 return 0;
4537
4538 flags = buf[l + 13] & 0x3f;
4539 }
4540 }
4541
4542 for (rule = ip_filters[filter].rules; rule->action; rule++)
4543 {
4544 if (rule->proto != IPPROTO_IP && proto != rule->proto)
4545 continue;
4546
4547 if (rule->src_wild != INADDR_BROADCAST &&
4548 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
4549 continue;
4550
4551 if (rule->dst_wild != INADDR_BROADCAST &&
4552 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
4553 continue;
4554
4555 if (frag_offset)
4556 {
4557 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
4558 continue;
4559 }
4560 else
4561 {
4562 if (rule->frag)
4563 continue;
4564
4565 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
4566 {
4567 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
4568 continue;
4569
4570 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
4571 continue;
4572
4573 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
4574 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
4575 continue;
4576 }
4577 }
4578
4579 // matched
4580 rule->counter++;
4581 return rule->action == FILTER_ACTION_PERMIT;
4582 }
4583
4584 // default deny
4585 return 0;
4586 }