missing newline on log message
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.73.2.7 2005/05/06 06:35:18 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("packet_limit", max_packets, INT),
121 CONFIG("cluster_address", cluster_address, IP),
122 CONFIG("cluster_interface", cluster_interface, STRING),
123 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
124 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
125 { NULL, 0, 0, 0 },
126 };
127
128 static char *plugin_functions[] = {
129 NULL,
130 "plugin_pre_auth",
131 "plugin_post_auth",
132 "plugin_packet_rx",
133 "plugin_packet_tx",
134 "plugin_timer",
135 "plugin_new_session",
136 "plugin_kill_session",
137 "plugin_control",
138 "plugin_radius_response",
139 "plugin_become_master",
140 "plugin_new_session_master",
141 };
142
143 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
144
145 // Counters for shutdown sessions
146 static sessiont shut_acct[8192];
147 static sessionidt shut_acct_n = 0;
148
149 tunnelt *tunnel = NULL; // Array of tunnel structures.
150 sessiont *session = NULL; // Array of session structures.
151 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
152 radiust *radius = NULL; // Array of radius structures.
153 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
154 ip_filtert *ip_filters = NULL; // Array of named filters.
155 static controlt *controlfree = 0;
156 struct Tstats *_statistics = NULL;
157 #ifdef RINGBUFFER
158 struct Tringbuffer *ringbuffer = NULL;
159 #endif
160
161 static void cache_ipmap(in_addr_t ip, int s);
162 static void uncache_ipmap(in_addr_t ip);
163 static void free_ip_address(sessionidt s);
164 static void dump_acct_info(int all);
165 static void sighup_handler(int sig);
166 static void sigalrm_handler(int sig);
167 static void sigterm_handler(int sig);
168 static void sigquit_handler(int sig);
169 static void sigchild_handler(int sig);
170 static void read_state(void);
171 static void dump_state(void);
172 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
173 static void update_config(void);
174 static void read_config_file(void);
175 static void initplugins(void);
176 static int add_plugin(char *plugin_name);
177 static int remove_plugin(char *plugin_name);
178 static void plugins_done(void);
179 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
180 static tunnelidt new_tunnel(void);
181 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
182
183 // return internal time (10ths since process startup)
184 static clockt now(void)
185 {
186 struct timeval t;
187 gettimeofday(&t, 0);
188 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
189 }
190
191 // work out a retry time based on try number
192 // This is a straight bounded exponential backoff.
193 // Maximum re-try time is 32 seconds. (2^5).
194 clockt backoff(uint8_t try)
195 {
196 if (try > 5) try = 5; // max backoff
197 return now() + 10 * (1 << try);
198 }
199
200
201 //
202 // Log a debug message. Typically called via the LOG macro
203 //
204 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
205 {
206 static char message[65536] = {0};
207 static char message2[65536] = {0};
208 va_list ap;
209
210 #ifdef RINGBUFFER
211 if (ringbuffer)
212 {
213 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
214 ringbuffer->tail = 0;
215 if (ringbuffer->tail == ringbuffer->head)
216 if (++ringbuffer->head >= RINGBUFFER_SIZE)
217 ringbuffer->head = 0;
218
219 ringbuffer->buffer[ringbuffer->tail].level = level;
220 ringbuffer->buffer[ringbuffer->tail].session = s;
221 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
222 va_start(ap, format);
223 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
224 va_end(ap);
225 }
226 #endif
227
228 if (config->debug < level) return;
229
230 va_start(ap, format);
231 if (log_stream)
232 {
233 vsnprintf(message2, 65535, format, ap);
234 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
235 fprintf(log_stream, "%s", message);
236 }
237 else if (syslog_log)
238 {
239 vsnprintf(message2, 65535, format, ap);
240 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
241 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
242 }
243 va_end(ap);
244 }
245
246 void _log_hex(int level, const char *title, const char *data, int maxsize)
247 {
248 int i, j;
249 const uint8_t *d = (const uint8_t *) data;
250
251 if (config->debug < level) return;
252
253 // No support for _log_hex to syslog
254 if (log_stream)
255 {
256 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
257 setvbuf(log_stream, NULL, _IOFBF, 16384);
258
259 for (i = 0; i < maxsize; )
260 {
261 fprintf(log_stream, "%4X: ", i);
262 for (j = i; j < maxsize && j < (i + 16); j++)
263 {
264 fprintf(log_stream, "%02X ", d[j]);
265 if (j == i + 7)
266 fputs(": ", log_stream);
267 }
268
269 for (; j < i + 16; j++)
270 {
271 fputs(" ", log_stream);
272 if (j == i + 7)
273 fputs(": ", log_stream);
274 }
275
276 fputs(" ", log_stream);
277 for (j = i; j < maxsize && j < (i + 16); j++)
278 {
279 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
280 fputc(d[j], log_stream);
281 else
282 fputc('.', log_stream);
283
284 if (j == i + 7)
285 fputs(" ", log_stream);
286 }
287
288 i = j;
289 fputs("\n", log_stream);
290 }
291
292 fflush(log_stream);
293 setbuf(log_stream, NULL);
294 }
295 }
296
297
298 // Add a route
299 //
300 // This adds it to the routing table, advertises it
301 // via BGP if enabled, and stuffs it into the
302 // 'sessionbyip' cache.
303 //
304 // 'ip' and 'mask' must be in _host_ order.
305 //
306 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
307 {
308 struct rtentry r;
309 int i;
310
311 if (!mask) mask = 0xffffffff;
312
313 ip &= mask; // Force the ip to be the first one in the route.
314
315 memset(&r, 0, sizeof(r));
316 r.rt_dev = config->tundevice;
317 r.rt_dst.sa_family = AF_INET;
318 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
319 r.rt_gateway.sa_family = AF_INET;
320 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
321 r.rt_genmask.sa_family = AF_INET;
322 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
323 r.rt_flags = (RTF_UP | RTF_STATIC);
324 if (gw)
325 r.rt_flags |= RTF_GATEWAY;
326 else if (mask == 0xffffffff)
327 r.rt_flags |= RTF_HOST;
328
329 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
330 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
331 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
332
333 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
334 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
335
336 #ifdef BGP
337 if (add)
338 bgp_add_route(htonl(ip), htonl(mask));
339 else
340 bgp_del_route(htonl(ip), htonl(mask));
341 #endif /* BGP */
342
343 // Add/Remove the IPs to the 'sessionbyip' cache.
344 // Note that we add the zero address in the case of
345 // a network route. Roll on CIDR.
346
347 // Note that 's == 0' implies this is the address pool.
348 // We still cache it here, because it will pre-fill
349 // the malloc'ed tree.
350
351 if (s)
352 {
353 if (!add) // Are we deleting a route?
354 s = 0; // Caching the session as '0' is the same as uncaching.
355
356 for (i = ip; (i&mask) == (ip&mask) ; ++i)
357 cache_ipmap(i, s);
358 }
359 }
360
361 //
362 // Set up TUN interface
363 static void inittun(void)
364 {
365 struct ifreq ifr;
366 struct sockaddr_in sin = {0};
367 memset(&ifr, 0, sizeof(ifr));
368 ifr.ifr_flags = IFF_TUN;
369
370 tunfd = open(TUNDEVICE, O_RDWR);
371 if (tunfd < 0)
372 { // fatal
373 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
374 exit(1);
375 }
376 {
377 int flags = fcntl(tunfd, F_GETFL, 0);
378 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
379 }
380 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
381 {
382 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
383 exit(1);
384 }
385 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
386 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
387 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
388
389 sin.sin_family = AF_INET;
390 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
391 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
392
393 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
394 {
395 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
396 exit(1);
397 }
398 /* Bump up the qlen to deal with bursts from the network */
399 ifr.ifr_qlen = 1000;
400 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
401 {
402 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
403 exit(1);
404 }
405 ifr.ifr_flags = IFF_UP;
406 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
407 {
408 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
409 exit(1);
410 }
411 }
412
413 // set up UDP port
414 static void initudp(void)
415 {
416 int on = 1;
417 struct sockaddr_in addr;
418
419 // Tunnel
420 memset(&addr, 0, sizeof(addr));
421 addr.sin_family = AF_INET;
422 addr.sin_port = htons(L2TPPORT);
423 addr.sin_addr.s_addr = config->bind_address;
424 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
425 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
426 {
427 int flags = fcntl(udpfd, F_GETFL, 0);
428 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
429 }
430 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
431 {
432 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
433 exit(1);
434 }
435 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
436
437 // Control
438 memset(&addr, 0, sizeof(addr));
439 addr.sin_family = AF_INET;
440 addr.sin_port = htons(NSCTL_PORT);
441 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
442 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
443 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
444 {
445 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
446 exit(1);
447 }
448 }
449
450 //
451 // Find session by IP, < 1 for not found
452 //
453 // Confusingly enough, this 'ip' must be
454 // in _network_ order. This being the common
455 // case when looking it up from IP packet headers.
456 //
457 // We actually use this cache for two things.
458 // #1. For used IP addresses, this maps to the
459 // session ID that it's used by.
460 // #2. For un-used IP addresses, this maps to the
461 // index into the pool table that contains that
462 // IP address.
463 //
464
465 static int lookup_ipmap(in_addr_t ip)
466 {
467 uint8_t *a = (uint8_t *) &ip;
468 uint8_t **d = (uint8_t **) ip_hash;
469
470 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
471 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
472 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
473
474 return (int) (intptr_t) d[(size_t) *a];
475 }
476
477 sessionidt sessionbyip(in_addr_t ip)
478 {
479 int s = lookup_ipmap(ip);
480 CSTAT(call_sessionbyip);
481
482 if (s > 0 && s < MAXSESSION && session[s].opened)
483 return (sessionidt) s;
484
485 return 0;
486 }
487
488 //
489 // Take an IP address in HOST byte order and
490 // add it to the sessionid by IP cache.
491 //
492 // (It's actually cached in network order)
493 //
494 static void cache_ipmap(in_addr_t ip, int s)
495 {
496 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
497 uint8_t *a = (uint8_t *) &nip;
498 uint8_t **d = (uint8_t **) ip_hash;
499 int i;
500
501 for (i = 0; i < 3; i++)
502 {
503 if (!d[(size_t) a[i]])
504 {
505 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
506 return;
507 }
508
509 d = (uint8_t **) d[(size_t) a[i]];
510 }
511
512 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
513
514 if (s > 0)
515 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
516
517 else if (s == 0)
518 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
519 // else a map to an ip pool index.
520 }
521
522 static void uncache_ipmap(in_addr_t ip)
523 {
524 cache_ipmap(ip, 0); // Assign it to the NULL session.
525 }
526
527 //
528 // CLI list to dump current ipcache.
529 //
530 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
531 {
532 char **d = (char **) ip_hash, **e, **f, **g;
533 int i, j, k, l;
534 int count = 0;
535
536 if (CLI_HELP_REQUESTED)
537 return CLI_HELP_NO_ARGS;
538
539 cli_print(cli, "%7s %s", "Sess#", "IP Address");
540
541 for (i = 0; i < 256; ++i)
542 {
543 if (!d[i])
544 continue;
545 e = (char **) d[i];
546 for (j = 0; j < 256; ++j)
547 {
548 if (!e[j])
549 continue;
550 f = (char **) e[j];
551 for (k = 0; k < 256; ++k)
552 {
553 if (!f[k])
554 continue;
555 g = (char **)f[k];
556 for (l = 0; l < 256; ++l)
557 {
558 if (!g[l])
559 continue;
560 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
561 ++count;
562 }
563 }
564 }
565 }
566 cli_print(cli, "%d entries in cache", count);
567 return CLI_OK;
568 }
569
570
571 // Find session by username, 0 for not found
572 // walled garden users aren't authenticated, so the username is
573 // reasonably useless. Ignore them to avoid incorrect actions
574 //
575 // This is VERY inefficent. Don't call it often. :)
576 //
577 sessionidt sessionbyuser(char *username)
578 {
579 int s;
580 CSTAT(call_sessionbyuser);
581
582 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
583 {
584 if (!session[s].opened)
585 continue;
586
587 if (session[s].walled_garden)
588 continue; // Skip walled garden users.
589
590 if (!strncmp(session[s].user, username, 128))
591 return s;
592
593 }
594 return 0; // Not found.
595 }
596
597 void send_garp(in_addr_t ip)
598 {
599 int s;
600 struct ifreq ifr;
601 uint8_t mac[6];
602
603 s = socket(PF_INET, SOCK_DGRAM, 0);
604 if (s < 0)
605 {
606 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
607 return;
608 }
609 memset(&ifr, 0, sizeof(ifr));
610 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
611 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
612 {
613 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
614 close(s);
615 return;
616 }
617 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
618 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
619 {
620 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
621 close(s);
622 return;
623 }
624 close(s);
625 sendarp(ifr.ifr_ifindex, mac, ip);
626 }
627
628 static sessiont *sessiontbysessionidt(sessionidt s)
629 {
630 if (!s || s >= MAXSESSION) return NULL;
631 return &session[s];
632 }
633
634 static sessionidt sessionidtbysessiont(sessiont *s)
635 {
636 sessionidt val = s-session;
637 if (s < session || val >= MAXSESSION) return 0;
638 return val;
639 }
640
641 // actually send a control message for a specific tunnel
642 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
643 {
644 struct sockaddr_in addr;
645
646 CSTAT(call_tunnelsend);
647
648 if (!t)
649 {
650 static int backtrace_count = 0;
651 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
652 STAT(tunnel_tx_errors);
653 log_backtrace(backtrace_count, 5)
654 return;
655 }
656
657 if (!tunnel[t].ip)
658 {
659 static int backtrace_count = 0;
660 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
661 log_backtrace(backtrace_count, 5)
662 STAT(tunnel_tx_errors);
663 return;
664 }
665
666 memset(&addr, 0, sizeof(addr));
667 addr.sin_family = AF_INET;
668 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
669 addr.sin_port = htons(tunnel[t].port);
670
671 // sequence expected, if sequence in message
672 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
673
674 // If this is a control message, deal with retries
675 if (*buf & 0x80)
676 {
677 tunnel[t].last = time_now; // control message sent
678 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
679 if (tunnel[t].try > 1)
680 {
681 STAT(tunnel_retries);
682 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
683 }
684 }
685
686 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
687 {
688 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
689 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
690 STAT(tunnel_tx_errors);
691 return;
692 }
693
694 LOG_HEX(5, "Send Tunnel Data", buf, l);
695 STAT(tunnel_tx_packets);
696 INC_STAT(tunnel_tx_bytes, l);
697 }
698
699 //
700 // Tiny helper function to write data to
701 // the 'tun' device.
702 //
703 int tun_write(uint8_t * data, int size)
704 {
705 return write(tunfd, data, size);
706 }
707
708 // process outgoing (to tunnel) IP
709 //
710 static void processipout(uint8_t * buf, int len)
711 {
712 sessionidt s;
713 sessiont *sp;
714 tunnelidt t;
715 in_addr_t ip;
716
717 char *data = buf; // Keep a copy of the originals.
718 int size = len;
719
720 uint8_t b[MAXETHER + 20];
721
722 CSTAT(call_processipout);
723
724 if (len < MIN_IP_SIZE)
725 {
726 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
727 STAT(tun_rx_errors);
728 return;
729 }
730 if (len >= MAXETHER)
731 {
732 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
733 STAT(tun_rx_errors);
734 return;
735 }
736
737 // Skip the tun header
738 buf += 4;
739 len -= 4;
740
741 // Got an IP header now
742 if (*(uint8_t *)(buf) >> 4 != 4)
743 {
744 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
745 return;
746 }
747
748 ip = *(uint32_t *)(buf + 16);
749 if (!(s = sessionbyip(ip)))
750 {
751 // Is this a packet for a session that doesn't exist?
752 static int rate = 0; // Number of ICMP packets we've sent this second.
753 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
754
755 if (last != time_now)
756 {
757 last = time_now;
758 rate = 0;
759 }
760
761 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
762 {
763 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
764 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
765 }
766 return;
767 }
768 t = session[s].tunnel;
769 sp = &session[s];
770
771 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
772 if (config->max_packets > 0)
773 {
774 if (sess_local[s].last_packet_out == TIME)
775 {
776 int max = config->max_packets;
777
778 // All packets for throttled sessions are handled by the
779 // master, so further limit by using the throttle rate.
780 // A bit of a kludge, since throttle rate is in kbps,
781 // but should still be generous given our average DSL
782 // packet size is 200 bytes: a limit of 28kbps equates
783 // to around 180 packets per second.
784 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
785 max = sp->throttle_out;
786
787 if (++sess_local[s].packets_out > max)
788 {
789 sess_local[s].packets_dropped++;
790 return;
791 }
792 }
793 else
794 {
795 if (sess_local[s].packets_dropped)
796 {
797 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
798 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
799 sess_local[s].packets_dropped, sess_local[s].packets_out,
800 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
801 sp->user);
802 }
803
804 sess_local[s].last_packet_out = TIME;
805 sess_local[s].packets_out = 1;
806 sess_local[s].packets_dropped = 0;
807 }
808 }
809
810 // run access-list if any
811 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
812 return;
813
814 if (sp->tbf_out)
815 {
816 // Are we throttling this session?
817 if (config->cluster_iam_master)
818 tbf_queue_packet(sp->tbf_out, data, size);
819 else
820 master_throttle_packet(sp->tbf_out, data, size);
821 return;
822 }
823 else if (sp->walled_garden && !config->cluster_iam_master)
824 {
825 // We are walled-gardening this
826 master_garden_packet(s, data, size);
827 return;
828 }
829
830 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
831
832 // Add on L2TP header
833 {
834 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
835 if (!p) return;
836 tunnelsend(b, len + (p-b), t); // send it...
837 }
838
839 // Snooping this session, send it to intercept box
840 if (sp->snoop_ip && sp->snoop_port)
841 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
842
843 sp->cout += len; // byte count
844 sp->total_cout += len; // byte count
845 sp->pout++;
846 udp_tx += len;
847 sess_local[s].cout += len; // To send to master..
848 }
849
850 //
851 // Helper routine for the TBF filters.
852 // Used to send queued data in to the user!
853 //
854 static void send_ipout(sessionidt s, uint8_t *buf, int len)
855 {
856 sessiont *sp;
857 tunnelidt t;
858 in_addr_t ip;
859
860 uint8_t b[MAXETHER + 20];
861
862 if (len < 0 || len > MAXETHER)
863 {
864 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
865 return;
866 }
867
868 // Skip the tun header
869 buf += 4;
870 len -= 4;
871
872 ip = *(in_addr_t *)(buf + 16);
873
874 if (!session[s].ip)
875 return;
876
877 t = session[s].tunnel;
878 sp = &session[s];
879
880 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
881
882 // Add on L2TP header
883 {
884 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
885 if (!p) return;
886 tunnelsend(b, len + (p-b), t); // send it...
887 }
888
889 // Snooping this session.
890 if (sp->snoop_ip && sp->snoop_port)
891 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
892
893 sp->cout += len; // byte count
894 sp->total_cout += len; // byte count
895 sp->pout++;
896 udp_tx += len;
897 sess_local[s].cout += len; // To send to master..
898 }
899
900 // add an AVP (16 bit)
901 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
902 {
903 uint16_t l = (m ? 0x8008 : 0x0008);
904 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
905 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
906 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
907 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
908 c->length += 8;
909 }
910
911 // add an AVP (32 bit)
912 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
913 {
914 uint16_t l = (m ? 0x800A : 0x000A);
915 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
916 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
917 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
918 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
919 c->length += 10;
920 }
921
922 // add an AVP (32 bit)
923 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
924 {
925 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
926 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
927 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
928 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
929 memcpy(c->buf + c->length + 6, val, strlen(val));
930 c->length += 6 + strlen(val);
931 }
932
933 // add a binary AVP
934 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
935 {
936 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
937 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
938 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
939 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
940 memcpy(c->buf + c->length + 6, val, len);
941 c->length += 6 + len;
942 }
943
944 // new control connection
945 static controlt *controlnew(uint16_t mtype)
946 {
947 controlt *c;
948 if (!controlfree)
949 c = malloc(sizeof(controlt));
950 else
951 {
952 c = controlfree;
953 controlfree = c->next;
954 }
955 assert(c);
956 c->next = 0;
957 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
958 c->length = 12;
959 control16(c, 0, mtype, 1);
960 return c;
961 }
962
963 // send zero block if nothing is waiting
964 // (ZLB send).
965 static void controlnull(tunnelidt t)
966 {
967 uint8_t buf[12];
968 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
969 return;
970
971 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
972 *(uint16_t *) (buf + 2) = htons(12); // length
973 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
974 *(uint16_t *) (buf + 6) = htons(0); // session
975 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
976 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
977 tunnelsend(buf, 12, t);
978 }
979
980 // add a control message to a tunnel, and send if within window
981 static void controladd(controlt * c, tunnelidt t, sessionidt s)
982 {
983 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
984 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
985 *(uint16_t *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
986 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
987 tunnel[t].ns++; // advance sequence
988 // link in message in to queue
989 if (tunnel[t].controlc)
990 tunnel[t].controle->next = c;
991 else
992 tunnel[t].controls = c;
993
994 tunnel[t].controle = c;
995 tunnel[t].controlc++;
996
997 // send now if space in window
998 if (tunnel[t].controlc <= tunnel[t].window)
999 {
1000 tunnel[t].try = 0; // first send
1001 tunnelsend(c->buf, c->length, t);
1002 }
1003 }
1004
1005 //
1006 // Throttle or Unthrottle a session
1007 //
1008 // Throttle the data from/to through a session to no more than
1009 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1010 // user).
1011 //
1012 // If either value is -1, the current value is retained for that
1013 // direction.
1014 //
1015 void throttle_session(sessionidt s, int rate_in, int rate_out)
1016 {
1017 if (!session[s].opened)
1018 return; // No-one home.
1019
1020 if (!*session[s].user)
1021 return; // User not logged in
1022
1023 if (rate_in >= 0)
1024 {
1025 int bytes = rate_in * 1024 / 8; // kbits to bytes
1026 if (session[s].tbf_in)
1027 free_tbf(session[s].tbf_in);
1028
1029 if (rate_in > 0)
1030 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1031 else
1032 session[s].tbf_in = 0;
1033
1034 session[s].throttle_in = rate_in;
1035 }
1036
1037 if (rate_out >= 0)
1038 {
1039 int bytes = rate_out * 1024 / 8;
1040 if (session[s].tbf_out)
1041 free_tbf(session[s].tbf_out);
1042
1043 if (rate_out > 0)
1044 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1045 else
1046 session[s].tbf_out = 0;
1047
1048 session[s].throttle_out = rate_out;
1049 }
1050 }
1051
1052 // add/remove filters from session (-1 = no change)
1053 void filter_session(sessionidt s, int filter_in, int filter_out)
1054 {
1055 if (!session[s].opened)
1056 return; // No-one home.
1057
1058 if (!*session[s].user)
1059 return; // User not logged in
1060
1061 // paranoia
1062 if (filter_in > MAXFILTER) filter_in = -1;
1063 if (filter_out > MAXFILTER) filter_out = -1;
1064 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1065 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1066
1067 if (filter_in >= 0)
1068 {
1069 if (session[s].filter_in)
1070 ip_filters[session[s].filter_in - 1].used--;
1071
1072 if (filter_in > 0)
1073 ip_filters[filter_in - 1].used++;
1074
1075 session[s].filter_in = filter_in;
1076 }
1077
1078 if (filter_out >= 0)
1079 {
1080 if (session[s].filter_out)
1081 ip_filters[session[s].filter_out - 1].used--;
1082
1083 if (filter_out > 0)
1084 ip_filters[filter_out - 1].used++;
1085
1086 session[s].filter_out = filter_out;
1087 }
1088 }
1089
1090 // start tidy shutdown of session
1091 void sessionshutdown(sessionidt s, char *reason)
1092 {
1093 int walled_garden = session[s].walled_garden;
1094
1095
1096 CSTAT(call_sessionshutdown);
1097
1098 if (!session[s].opened)
1099 {
1100 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1101 return; // not a live session
1102 }
1103
1104 if (!session[s].die)
1105 {
1106 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1107 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1108 run_plugins(PLUGIN_KILL_SESSION, &data);
1109 }
1110
1111 if (session[s].ip && !walled_garden && !session[s].die)
1112 {
1113 // RADIUS Stop message
1114 uint16_t r = session[s].radius;
1115 if (!r)
1116 {
1117 if (!(r = radiusnew(s)))
1118 {
1119 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1120 STAT(radius_overflow);
1121 }
1122 else
1123 {
1124 int n;
1125 for (n = 0; n < 15; n++)
1126 radius[r].auth[n] = rand();
1127 }
1128 }
1129
1130 if (r && radius[r].state != RADIUSSTOP)
1131 radiussend(r, RADIUSSTOP); // stop, if not already trying
1132
1133 // Save counters to dump to accounting file
1134 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1135 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1136 }
1137
1138 if (session[s].ip)
1139 { // IP allocated, clear and unroute
1140 int r;
1141 int routed = 0;
1142 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1143 {
1144 if ((session[s].ip & session[s].route[r].mask) ==
1145 (session[s].route[r].ip & session[s].route[r].mask))
1146 routed++;
1147
1148 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1149 session[s].route[r].ip = 0;
1150 }
1151
1152 if (session[s].ip_pool_index == -1) // static ip
1153 {
1154 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1155 session[s].ip = 0;
1156 }
1157 else
1158 free_ip_address(s);
1159 }
1160
1161 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1162 throttle_session(s, 0, 0);
1163
1164 { // Send CDN
1165 controlt *c = controlnew(14); // sending CDN
1166 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1167 control16(c, 14, s, 1); // assigned session (our end)
1168 controladd(c, session[s].tunnel, s); // send the message
1169 }
1170
1171 if (!session[s].die)
1172 session[s].die = TIME + 150; // Clean up in 15 seconds
1173
1174 // update filter refcounts
1175 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1176 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1177
1178 cluster_send_session(s);
1179 }
1180
1181 void sendipcp(tunnelidt t, sessionidt s)
1182 {
1183 uint8_t buf[MAXCONTROL];
1184 uint16_t r = session[s].radius;
1185 uint8_t *q;
1186
1187 CSTAT(call_sendipcp);
1188
1189 if (!r)
1190 r = radiusnew(s);
1191
1192 if (radius[r].state != RADIUSIPCP)
1193 {
1194 radius[r].state = RADIUSIPCP;
1195 radius[r].try = 0;
1196 }
1197
1198 radius[r].retry = backoff(radius[r].try++);
1199 if (radius[r].try > 10)
1200 {
1201 radiusclear(r, s); // Clear radius session.
1202 sessionshutdown(s, "No reply on IPCP");
1203 return;
1204 }
1205
1206 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1207 if (!q) return;
1208
1209 *q = ConfigReq;
1210 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1211 *(uint16_t *) (q + 2) = htons(10);
1212 q[4] = 3;
1213 q[5] = 6;
1214 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1215 config->bind_address ? config->bind_address :
1216 my_address; // send my IP
1217
1218 tunnelsend(buf, 10 + (q - buf), t); // send it
1219 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1220 }
1221
1222 // kill a session now
1223 void sessionkill(sessionidt s, char *reason)
1224 {
1225
1226 CSTAT(call_sessionkill);
1227
1228 if (!session[s].opened) // not alive
1229 return;
1230
1231 if (session[s].next)
1232 {
1233 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1234 return;
1235 }
1236
1237 session[s].die = TIME;
1238 sessionshutdown(s, reason); // close radius/routes, etc.
1239 if (session[s].radius)
1240 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1241
1242 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1243
1244 memset(&session[s], 0, sizeof(session[s]));
1245 session[s].tunnel = T_FREE; // Mark it as free.
1246 session[s].next = sessionfree;
1247 sessionfree = s;
1248 cli_session_actions[s].action = 0;
1249 cluster_send_session(s);
1250 }
1251
1252 static void tunnelclear(tunnelidt t)
1253 {
1254 if (!t) return;
1255 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1256 tunnel[t].state = TUNNELFREE;
1257 }
1258
1259 // kill a tunnel now
1260 static void tunnelkill(tunnelidt t, char *reason)
1261 {
1262 sessionidt s;
1263 controlt *c;
1264
1265 CSTAT(call_tunnelkill);
1266
1267 tunnel[t].state = TUNNELDIE;
1268
1269 // free control messages
1270 while ((c = tunnel[t].controls))
1271 {
1272 controlt * n = c->next;
1273 tunnel[t].controls = n;
1274 tunnel[t].controlc--;
1275 c->next = controlfree;
1276 controlfree = c;
1277 }
1278 // kill sessions
1279 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1280 if (session[s].tunnel == t)
1281 sessionkill(s, reason);
1282
1283 // free tunnel
1284 tunnelclear(t);
1285 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1286 cli_tunnel_actions[s].action = 0;
1287 cluster_send_tunnel(t);
1288 }
1289
1290 // shut down a tunnel cleanly
1291 static void tunnelshutdown(tunnelidt t, char *reason)
1292 {
1293 sessionidt s;
1294
1295 CSTAT(call_tunnelshutdown);
1296
1297 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1298 {
1299 // never set up, can immediately kill
1300 tunnelkill(t, reason);
1301 return;
1302 }
1303 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1304
1305 // close session
1306 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1307 if (session[s].tunnel == t)
1308 sessionshutdown(s, reason);
1309
1310 tunnel[t].state = TUNNELDIE;
1311 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1312 cluster_send_tunnel(t);
1313 // TBA - should we wait for sessions to stop?
1314 { // Send StopCCN
1315 controlt *c = controlnew(4); // sending StopCCN
1316 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message)
1317 control16(c, 9, t, 1); // assigned tunnel (our end)
1318 controladd(c, t, 0); // send the message
1319 }
1320 }
1321
1322 // read and process packet on tunnel (UDP)
1323 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1324 {
1325 char *chapresponse = NULL;
1326 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1327 uint8_t *p = buf + 2;
1328
1329
1330 CSTAT(call_processudp);
1331
1332 udp_rx += len;
1333 udp_rx_pkt++;
1334 LOG_HEX(5, "UDP Data", buf, len);
1335 STAT(tunnel_rx_packets);
1336 INC_STAT(tunnel_rx_bytes, len);
1337 if (len < 6)
1338 {
1339 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1340 STAT(tunnel_rx_errors);
1341 return;
1342 }
1343 if ((buf[1] & 0x0F) != 2)
1344 {
1345 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1346 STAT(tunnel_rx_errors);
1347 return;
1348 }
1349 if (*buf & 0x40)
1350 { // length
1351 l = ntohs(*(uint16_t *) p);
1352 p += 2;
1353 }
1354 t = ntohs(*(uint16_t *) p);
1355 p += 2;
1356 s = ntohs(*(uint16_t *) p);
1357 p += 2;
1358 if (s >= MAXSESSION)
1359 {
1360 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1361 STAT(tunnel_rx_errors);
1362 return;
1363 }
1364 if (t >= MAXTUNNEL)
1365 {
1366 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1367 STAT(tunnel_rx_errors);
1368 return;
1369 }
1370 if (*buf & 0x08)
1371 { // ns/nr
1372 ns = ntohs(*(uint16_t *) p);
1373 p += 2;
1374 nr = ntohs(*(uint16_t *) p);
1375 p += 2;
1376 }
1377 if (*buf & 0x02)
1378 { // offset
1379 uint16_t o = ntohs(*(uint16_t *) p);
1380 p += o + 2;
1381 }
1382 if ((p - buf) > l)
1383 {
1384 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1385 STAT(tunnel_rx_errors);
1386 return;
1387 }
1388 l -= (p - buf);
1389 if (*buf & 0x80)
1390 { // control
1391 uint16_t message = 0xFFFF; // message type
1392 uint8_t fatal = 0;
1393 uint8_t mandatorymessage = 0;
1394 uint8_t chap = 0; // if CHAP being used
1395 uint16_t asession = 0; // assigned session
1396 uint32_t amagic = 0; // magic number
1397 uint8_t aflags = 0; // flags from last LCF
1398 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1399 int requestchap = 0; // do we request PAP instead of original CHAP request?
1400 char called[MAXTEL] = ""; // called number
1401 char calling[MAXTEL] = ""; // calling number
1402
1403 if (!config->cluster_iam_master)
1404 {
1405 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1406 return;
1407 }
1408
1409 if ((*buf & 0xCA) != 0xC8)
1410 {
1411 LOG(1, s, t, "Bad control header %02X\n", *buf);
1412 STAT(tunnel_rx_errors);
1413 return;
1414 }
1415
1416 // check for duplicate tunnel open message
1417 if (!t && ns == 0)
1418 {
1419 int i;
1420
1421 //
1422 // Is this a duplicate of the first packet? (SCCRQ)
1423 //
1424 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1425 {
1426 if (tunnel[i].state != TUNNELOPENING ||
1427 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1428 tunnel[i].port != ntohs(addr->sin_port) )
1429 continue;
1430 t = i;
1431 LOG(3, s, t, "Duplicate SCCRQ?\n");
1432 break;
1433 }
1434 }
1435
1436 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1437 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1438
1439 // if no tunnel specified, assign one
1440 if (!t)
1441 {
1442 if (!(t = new_tunnel()))
1443 {
1444 LOG(1, 0, 0, "No more tunnels\n");
1445 STAT(tunnel_overflow);
1446 return;
1447 }
1448 tunnelclear(t);
1449 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1450 tunnel[t].port = ntohs(addr->sin_port);
1451 tunnel[t].window = 4; // default window
1452 STAT(tunnel_created);
1453 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1454 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1455 }
1456
1457 // If the 'ns' just received is not the 'nr' we're
1458 // expecting, just send an ack and drop it.
1459 //
1460 // if 'ns' is less, then we got a retransmitted packet.
1461 // if 'ns' is greater than missed a packet. Either way
1462 // we should ignore it.
1463 if (ns != tunnel[t].nr)
1464 {
1465 // is this the sequence we were expecting?
1466 STAT(tunnel_rx_errors);
1467 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1468 t, ns, tunnel[t].nr);
1469
1470 if (l) // Is this not a ZLB?
1471 controlnull(t);
1472 return;
1473 }
1474
1475 // This is used to time out old tunnels
1476 tunnel[t].lastrec = time_now;
1477
1478 // check sequence of this message
1479 {
1480 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1481 // some to clear maybe?
1482 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1483 {
1484 controlt *c = tunnel[t].controls;
1485 tunnel[t].controls = c->next;
1486 tunnel[t].controlc--;
1487 c->next = controlfree;
1488 controlfree = c;
1489 skip--;
1490 tunnel[t].try = 0; // we have progress
1491 }
1492
1493 // receiver advance (do here so quoted correctly in any sends below)
1494 if (l) tunnel[t].nr = (ns + 1);
1495 if (skip < 0) skip = 0;
1496 if (skip < tunnel[t].controlc)
1497 {
1498 // some control packets can now be sent that were previous stuck out of window
1499 int tosend = tunnel[t].window - skip;
1500 controlt *c = tunnel[t].controls;
1501 while (c && skip)
1502 {
1503 c = c->next;
1504 skip--;
1505 }
1506 while (c && tosend)
1507 {
1508 tunnel[t].try = 0; // first send
1509 tunnelsend(c->buf, c->length, t);
1510 c = c->next;
1511 tosend--;
1512 }
1513 }
1514 if (!tunnel[t].controlc)
1515 tunnel[t].retry = 0; // caught up
1516 }
1517 if (l)
1518 { // if not a null message
1519 // process AVPs
1520 while (l && !(fatal & 0x80))
1521 {
1522 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1523 uint8_t *b = p;
1524 uint8_t flags = *p;
1525 uint16_t mtype;
1526 p += n; // next
1527 if (l < n)
1528 {
1529 LOG(1, s, t, "Invalid length in AVP\n");
1530 STAT(tunnel_rx_errors);
1531 fatal = flags;
1532 return;
1533 }
1534 l -= n;
1535 if (flags & 0x40)
1536 {
1537 // handle hidden AVPs
1538 if (!*config->l2tpsecret)
1539 {
1540 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
1541 fatal = flags;
1542 continue;
1543 }
1544 if (!session[s].random_vector_length)
1545 {
1546 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
1547 fatal = flags;
1548 continue;
1549 }
1550 LOG(4, s, t, "Hidden AVP\n");
1551 // Unhide the AVP
1552 n = unhide_avp(b, t, s, n);
1553 if (n == 0)
1554 {
1555 fatal = flags;
1556 continue;
1557 }
1558 }
1559 if (*b & 0x3C)
1560 {
1561 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1562 fatal = flags;
1563 continue; // next
1564 }
1565 b += 2;
1566 if (*(uint16_t *) (b))
1567 {
1568 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1569 fatal = flags;
1570 continue; // next
1571 }
1572 b += 2;
1573 mtype = ntohs(*(uint16_t *) (b));
1574 b += 2;
1575 n -= 6;
1576
1577 LOG(4, s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1578 switch (mtype)
1579 {
1580 case 0: // message type
1581 message = ntohs(*(uint16_t *) b);
1582 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_types[message]);
1583 mandatorymessage = flags;
1584 break;
1585 case 1: // result code
1586 {
1587 uint16_t rescode = ntohs(*(uint16_t *) b);
1588 const char* resdesc = "(unknown)";
1589 if (message == 4)
1590 { /* StopCCN */
1591 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1592 resdesc = stopccn_result_codes[rescode];
1593 }
1594 else if (message == 14)
1595 { /* CDN */
1596 if (rescode <= MAX_CDN_RESULT_CODE)
1597 resdesc = cdn_result_codes[rescode];
1598 }
1599
1600 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
1601 if (n >= 4)
1602 {
1603 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
1604 const char* errdesc = "(unknown)";
1605 if (errcode <= MAX_ERROR_CODE)
1606 errdesc = error_codes[errcode];
1607 LOG(4, s, t, " Error Code %d: %s\n", errcode, errdesc);
1608 }
1609 if (n > 4)
1610 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
1611
1612 break;
1613 }
1614 break;
1615 case 2: // protocol version
1616 {
1617 version = ntohs(*(uint16_t *) (b));
1618 LOG(4, s, t, " Protocol version = %d\n", version);
1619 if (version && version != 0x0100)
1620 { // allow 0.0 and 1.0
1621 LOG(1, s, t, " Bad protocol version %04X\n", version);
1622 fatal = flags;
1623 continue; // next
1624 }
1625 }
1626 break;
1627 case 3: // framing capabilities
1628 // LOG(4, s, t, "Framing capabilities\n");
1629 break;
1630 case 4: // bearer capabilities
1631 // LOG(4, s, t, "Bearer capabilities\n");
1632 break;
1633 case 5: // tie breaker
1634 // We never open tunnels, so we don't care about tie breakers
1635 // LOG(4, s, t, "Tie breaker\n");
1636 continue;
1637 case 6: // firmware revision
1638 // LOG(4, s, t, "Firmware revision\n");
1639 break;
1640 case 7: // host name
1641 memset(tunnel[t].hostname, 0, 128);
1642 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1643 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1644 // TBA - to send to RADIUS
1645 break;
1646 case 8: // vendor name
1647 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1648 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1649 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1650 break;
1651 case 9: // assigned tunnel
1652 tunnel[t].far = ntohs(*(uint16_t *) (b));
1653 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1654 break;
1655 case 10: // rx window
1656 tunnel[t].window = ntohs(*(uint16_t *) (b));
1657 if (!tunnel[t].window)
1658 tunnel[t].window = 1; // window of 0 is silly
1659 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
1660 break;
1661 case 11: // Challenge
1662 {
1663 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
1664 build_chap_response(b, 2, n, &chapresponse);
1665 }
1666 break;
1667 case 13: // Response
1668 // Why did they send a response? We never challenge.
1669 LOG(2, s, t, " received unexpected challenge response\n");
1670 break;
1671
1672 case 14: // assigned session
1673 asession = session[s].far = ntohs(*(uint16_t *) (b));
1674 LOG(4, s, t, " assigned session = %d\n", asession);
1675 break;
1676 case 15: // call serial number
1677 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
1678 break;
1679 case 18: // bearer type
1680 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
1681 // TBA - for RADIUS
1682 break;
1683 case 19: // framing type
1684 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
1685 // TBA
1686 break;
1687 case 21: // called number
1688 memset(called, 0, MAXTEL);
1689 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1690 LOG(4, s, t, " Called <%s>\n", called);
1691 break;
1692 case 22: // calling number
1693 memset(calling, 0, MAXTEL);
1694 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1695 LOG(4, s, t, " Calling <%s>\n", calling);
1696 break;
1697 case 23: // subtype
1698 break;
1699 case 24: // tx connect speed
1700 if (n == 4)
1701 {
1702 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
1703 }
1704 else
1705 {
1706 // AS5300s send connect speed as a string
1707 char tmp[30] = {0};
1708 memcpy(tmp, b, (n >= 30) ? 30 : n);
1709 session[s].tx_connect_speed = atol(tmp);
1710 }
1711 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
1712 break;
1713 case 38: // rx connect speed
1714 if (n == 4)
1715 {
1716 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
1717 }
1718 else
1719 {
1720 // AS5300s send connect speed as a string
1721 char tmp[30] = {0};
1722 memcpy(tmp, b, (n >= 30) ? 30 : n);
1723 session[s].rx_connect_speed = atol(tmp);
1724 }
1725 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
1726 break;
1727 case 25: // Physical Channel ID
1728 {
1729 uint32_t tmp = ntohl(*(uint32_t *) b);
1730 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
1731 break;
1732 }
1733 case 29: // Proxy Authentication Type
1734 {
1735 uint16_t authtype = ntohs(*(uint16_t *)b);
1736 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", authtype, authtypes[authtype]);
1737 requestchap = (authtype == 2);
1738 break;
1739 }
1740 case 30: // Proxy Authentication Name
1741 {
1742 char authname[64] = {0};
1743 memcpy(authname, b, (n > 63) ? 63 : n);
1744 LOG(4, s, t, " Proxy Auth Name (%s)\n",
1745 authname);
1746 break;
1747 }
1748 case 31: // Proxy Authentication Challenge
1749 {
1750 memcpy(radius[session[s].radius].auth, b, 16);
1751 LOG(4, s, t, " Proxy Auth Challenge\n");
1752 break;
1753 }
1754 case 32: // Proxy Authentication ID
1755 {
1756 uint16_t authid = ntohs(*(uint16_t *)(b));
1757 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
1758 if (session[s].radius)
1759 radius[session[s].radius].id = authid;
1760 break;
1761 }
1762 case 33: // Proxy Authentication Response
1763 {
1764 char authresp[64] = {0};
1765 memcpy(authresp, b, (n > 63) ? 63 : n);
1766 LOG(4, s, t, " Proxy Auth Response\n");
1767 break;
1768 }
1769 case 27: // last send lcp
1770 { // find magic number
1771 uint8_t *p = b, *e = p + n;
1772 while (p + 1 < e && p[1] && p + p[1] <= e)
1773 {
1774 if (*p == 5 && p[1] == 6) // Magic-Number
1775 amagic = ntohl(*(uint32_t *) (p + 2));
1776 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
1777 chap = 1;
1778 else if (*p == 7) // Protocol-Field-Compression
1779 aflags |= SESSIONPFC;
1780 else if (*p == 8) // Address-and-Control-Field-Compression
1781 aflags |= SESSIONACFC;
1782 p += p[1];
1783 }
1784 }
1785 break;
1786 case 28: // last recv lcp confreq
1787 break;
1788 case 26: // Initial Received LCP CONFREQ
1789 break;
1790 case 39: // seq required - we control it as an LNS anyway...
1791 break;
1792 case 36: // Random Vector
1793 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
1794 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1795 memcpy(session[s].random_vector, b, n);
1796 session[s].random_vector_length = n;
1797 break;
1798 default:
1799 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
1800 fatal = flags;
1801 continue; // next
1802 }
1803 }
1804 // process message
1805 if (fatal & 0x80)
1806 tunnelshutdown(t, "Unknown Mandatory AVP");
1807 else
1808 switch (message)
1809 {
1810 case 1: // SCCRQ - Start Control Connection Request
1811 {
1812 controlt *c = controlnew(2); // sending SCCRP
1813 control16(c, 2, version, 1); // protocol version
1814 control32(c, 3, 3, 1); // framing
1815 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1816 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1817 control16(c, 9, t, 1); // assigned tunnel
1818 controladd(c, t, s); // send the resply
1819 }
1820 tunnel[t].state = TUNNELOPENING;
1821 break;
1822 case 2: // SCCRP
1823 tunnel[t].state = TUNNELOPEN;
1824 break;
1825 case 3: // SCCN
1826 tunnel[t].state = TUNNELOPEN;
1827 controlnull(t); // ack
1828 break;
1829 case 4: // StopCCN
1830 controlnull(t); // ack
1831 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1832 tunnelkill(t, "Stopped"); // Immediately force everything dead
1833 break;
1834 case 6: // HELLO
1835 controlnull(t); // simply ACK
1836 break;
1837 case 7: // OCRQ
1838 // TBA
1839 break;
1840 case 8: // OCRO
1841 // TBA
1842 break;
1843 case 9: // OCCN
1844 // TBA
1845 break;
1846 case 10: // ICRQ
1847 if (!sessionfree)
1848 {
1849 STAT(session_overflow);
1850 LOG(1, 0, t, "No free sessions\n");
1851 return;
1852 }
1853 else
1854 {
1855 uint16_t r;
1856 controlt *c;
1857
1858 s = sessionfree;
1859 sessionfree = session[s].next;
1860 memset(&session[s], 0, sizeof(session[s]));
1861
1862 if (s > config->cluster_highest_sessionid)
1863 config->cluster_highest_sessionid = s;
1864
1865 // make a RADIUS session
1866 if (!(r = radiusnew(s)))
1867 {
1868 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
1869 sessionkill(s, "no free RADIUS sesions");
1870 return;
1871 }
1872
1873 c = controlnew(11); // sending ICRP
1874 session[s].id = sessionid++;
1875 session[s].opened = time_now;
1876 session[s].tunnel = t;
1877 session[s].far = asession;
1878 session[s].last_packet = time_now;
1879 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1880 control16(c, 14, s, 1); // assigned session
1881 controladd(c, t, s); // send the reply
1882 {
1883 // Generate a random challenge
1884 int n;
1885 for (n = 0; n < 15; n++)
1886 radius[r].auth[n] = rand();
1887 }
1888 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1889 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1890 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1891 STAT(session_created);
1892 }
1893 break;
1894 case 11: // ICRP
1895 // TBA
1896 break;
1897 case 12: // ICCN
1898 if (amagic == 0) amagic = time_now;
1899 session[s].magic = amagic; // set magic number
1900 session[s].l2tp_flags = aflags; // set flags received
1901 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
1902 controlnull(t); // ack
1903 // In CHAP state, request PAP instead
1904 if (requestchap)
1905 initlcp(t, s);
1906 break;
1907 case 14: // CDN
1908 controlnull(t); // ack
1909 sessionshutdown(s, "Closed (Received CDN)");
1910 break;
1911 case 0xFFFF:
1912 LOG(1, s, t, "Missing message type\n");
1913 break;
1914 default:
1915 STAT(tunnel_rx_errors);
1916 if (mandatorymessage & 0x80)
1917 tunnelshutdown(t, "Unknown message");
1918 else
1919 LOG(1, s, t, "Unknown message type %d\n", message);
1920 break;
1921 }
1922 if (chapresponse) free(chapresponse);
1923 cluster_send_tunnel(t);
1924 }
1925 else
1926 {
1927 LOG(4, s, t, " Got a ZLB ack\n");
1928 }
1929 }
1930 else
1931 { // data
1932 uint16_t prot;
1933
1934 LOG_HEX(5, "Receive Tunnel Data", p, l);
1935 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1936 { // HDLC address header, discard
1937 p += 2;
1938 l -= 2;
1939 }
1940 if (l < 2)
1941 {
1942 LOG(1, s, t, "Short ppp length %d\n", l);
1943 STAT(tunnel_rx_errors);
1944 return;
1945 }
1946 if (*p & 1)
1947 {
1948 prot = *p++;
1949 l--;
1950 }
1951 else
1952 {
1953 prot = ntohs(*(uint16_t *) p);
1954 p += 2;
1955 l -= 2;
1956 }
1957
1958 if (s && !session[s].opened) // Is something wrong??
1959 {
1960 if (!config->cluster_iam_master)
1961 {
1962 // Pass it off to the master to deal with..
1963 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1964 return;
1965 }
1966
1967 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
1968 STAT(tunnel_rx_errors);
1969 return;
1970 }
1971
1972 if (prot == PPPPAP)
1973 {
1974 session[s].last_packet = time_now;
1975 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1976 processpap(t, s, p, l);
1977 }
1978 else if (prot == PPPCHAP)
1979 {
1980 session[s].last_packet = time_now;
1981 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1982 processchap(t, s, p, l);
1983 }
1984 else if (prot == PPPLCP)
1985 {
1986 session[s].last_packet = time_now;
1987 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1988 processlcp(t, s, p, l);
1989 }
1990 else if (prot == PPPIPCP)
1991 {
1992 session[s].last_packet = time_now;
1993 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1994 processipcp(t, s, p, l);
1995 }
1996 else if (prot == PPPCCP)
1997 {
1998 session[s].last_packet = time_now;
1999 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2000 processccp(t, s, p, l);
2001 }
2002 else if (prot == PPPIP)
2003 {
2004 if (session[s].die)
2005 {
2006 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2007 return; // closing session, PPP not processed
2008 }
2009
2010 session[s].last_packet = time_now;
2011 if (session[s].walled_garden && !config->cluster_iam_master)
2012 {
2013 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2014 return;
2015 }
2016
2017 processipin(t, s, p, l);
2018 }
2019 else
2020 {
2021 STAT(tunnel_rx_errors);
2022 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2023 }
2024 }
2025 }
2026
2027 // read and process packet on tun
2028 static void processtun(uint8_t * buf, int len)
2029 {
2030 LOG_HEX(5, "Receive TUN Data", buf, len);
2031 STAT(tun_rx_packets);
2032 INC_STAT(tun_rx_bytes, len);
2033
2034 CSTAT(call_processtun);
2035
2036 eth_rx_pkt++;
2037 eth_rx += len;
2038 if (len < 22)
2039 {
2040 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2041 STAT(tun_rx_errors);
2042 return;
2043 }
2044
2045 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IP
2046 processipout(buf, len);
2047 // Else discard.
2048 }
2049
2050 //
2051 // Maximum number of actions to complete.
2052 // This is to avoid sending out too many packets
2053 // at once.
2054 #define MAX_ACTIONS 500
2055
2056 static int regular_cleanups(void)
2057 {
2058 static sessionidt s = 0; // Next session to check for actions on.
2059 tunnelidt t;
2060 int count=0,i;
2061 uint16_t r;
2062 static clockt next_acct = 0;
2063 static clockt next_shut_acct = 0;
2064 int a;
2065
2066 LOG(3, 0, 0, "Begin regular cleanup\n");
2067
2068 for (r = 1; r < MAXRADIUS; r++)
2069 {
2070 if (!radius[r].state)
2071 continue;
2072 if (radius[r].retry)
2073 {
2074 if (radius[r].retry <= TIME)
2075 radiusretry(r);
2076 } else
2077 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2078 }
2079 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
2080 {
2081 // check for expired tunnels
2082 if (tunnel[t].die && tunnel[t].die <= TIME)
2083 {
2084 STAT(tunnel_timeout);
2085 tunnelkill(t, "Expired");
2086 continue;
2087 }
2088 // check for message resend
2089 if (tunnel[t].retry && tunnel[t].controlc)
2090 {
2091 // resend pending messages as timeout on reply
2092 if (tunnel[t].retry <= TIME)
2093 {
2094 controlt *c = tunnel[t].controls;
2095 uint8_t w = tunnel[t].window;
2096 tunnel[t].try++; // another try
2097 if (tunnel[t].try > 5)
2098 tunnelkill(t, "Timeout on control message"); // game over
2099 else
2100 while (c && w--)
2101 {
2102 tunnelsend(c->buf, c->length, t);
2103 c = c->next;
2104 }
2105 }
2106 }
2107 // Send hello
2108 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2109 {
2110 controlt *c = controlnew(6); // sending HELLO
2111 controladd(c, t, 0); // send the message
2112 LOG(3, 0, t, "Sending HELLO message\n");
2113 }
2114
2115 // Check for tunnel changes requested from the CLI
2116 if ((a = cli_tunnel_actions[t].action))
2117 {
2118 cli_tunnel_actions[t].action = 0;
2119 if (a & CLI_TUN_KILL)
2120 {
2121 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2122 tunnelshutdown(t, "Requested by administrator");
2123 }
2124 }
2125
2126 }
2127
2128 count = 0;
2129 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2130 {
2131 s++;
2132 if (s > config->cluster_highest_sessionid)
2133 s = 1;
2134
2135 if (!session[s].opened) // Session isn't in use
2136 continue;
2137
2138 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2139 {
2140 // IPCP has not completed yet. Resend
2141 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2142 sendipcp(session[s].tunnel, s);
2143 }
2144
2145 // check for expired sessions
2146 if (session[s].die && session[s].die <= TIME)
2147 {
2148 sessionkill(s, "Expired");
2149 if (++count >= MAX_ACTIONS) break;
2150 continue;
2151 }
2152
2153 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2154 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2155 {
2156 sessionshutdown(s, "No response to LCP ECHO requests");
2157 STAT(session_timeout);
2158 if (++count >= MAX_ACTIONS) break;
2159 continue;
2160 }
2161
2162 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2163 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2164 {
2165 uint8_t b[MAXCONTROL] = {0};
2166
2167 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2168 if (!q) continue;
2169
2170 *q = EchoReq;
2171 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2172 *(uint16_t *)(q + 2) = htons(8); // Length
2173 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2174
2175 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2176 (int)(time_now - session[s].last_packet));
2177 tunnelsend(b, 24, session[s].tunnel); // send it
2178 if (++count >= MAX_ACTIONS) break;
2179 }
2180
2181 // Check for actions requested from the CLI
2182 if ((a = cli_session_actions[s].action))
2183 {
2184 int send = 0;
2185
2186 cli_session_actions[s].action = 0;
2187 if (a & CLI_SESS_KILL)
2188 {
2189 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2190 sessionshutdown(s, "Requested by administrator");
2191 a = 0; // dead, no need to check for other actions
2192 }
2193
2194 if (a & CLI_SESS_NOSNOOP)
2195 {
2196 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2197 session[s].snoop_ip = 0;
2198 session[s].snoop_port = 0;
2199 send++;
2200 }
2201 else if (a & CLI_SESS_SNOOP)
2202 {
2203 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2204 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2205 cli_session_actions[s].snoop_port);
2206
2207 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2208 session[s].snoop_port = cli_session_actions[s].snoop_port;
2209 send++;
2210 }
2211
2212 if (a & CLI_SESS_NOTHROTTLE)
2213 {
2214 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2215 throttle_session(s, 0, 0);
2216 send++;
2217 }
2218 else if (a & CLI_SESS_THROTTLE)
2219 {
2220 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2221 cli_session_actions[s].throttle_in,
2222 cli_session_actions[s].throttle_out);
2223
2224 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2225 send++;
2226 }
2227
2228 if (a & CLI_SESS_NOFILTER)
2229 {
2230 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2231 filter_session(s, 0, 0);
2232 send++;
2233 }
2234 else if (a & CLI_SESS_FILTER)
2235 {
2236 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2237 cli_session_actions[s].filter_in,
2238 cli_session_actions[s].filter_out);
2239
2240 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2241 send++;
2242 }
2243
2244 if (send)
2245 cluster_send_session(s);
2246
2247 if (++count >= MAX_ACTIONS) break;
2248 }
2249 }
2250
2251 if (*config->accounting_dir)
2252 {
2253 if (next_acct <= TIME)
2254 {
2255 // Dump accounting data
2256 next_acct = TIME + ACCT_TIME;
2257 next_shut_acct = TIME + ACCT_SHUT_TIME;
2258 dump_acct_info(1);
2259 }
2260 else if (next_shut_acct <= TIME)
2261 {
2262 // Dump accounting data for shutdown sessions
2263 next_shut_acct = TIME + ACCT_SHUT_TIME;
2264 if (shut_acct_n)
2265 dump_acct_info(0);
2266 }
2267 }
2268
2269 if (count >= MAX_ACTIONS)
2270 return 1; // Didn't finish!
2271
2272 LOG(3, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2273 return 0;
2274 }
2275
2276
2277 //
2278 // Are we in the middle of a tunnel update, or radius
2279 // requests??
2280 //
2281 static int still_busy(void)
2282 {
2283 int i;
2284 static clockt last_talked = 0;
2285 static clockt start_busy_wait = 0;
2286 if (start_busy_wait == 0)
2287 start_busy_wait = TIME;
2288
2289 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2290 {
2291 if (!tunnel[i].controlc)
2292 continue;
2293
2294 if (last_talked != TIME)
2295 {
2296 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2297 last_talked = TIME;
2298 }
2299 return 1;
2300 }
2301
2302 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2303 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2304 {
2305 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2306 return 0;
2307 }
2308
2309 for (i = 1; i < MAXRADIUS; i++)
2310 {
2311 if (radius[i].state == RADIUSNULL)
2312 continue;
2313 if (radius[i].state == RADIUSWAIT)
2314 continue;
2315
2316 if (last_talked != TIME)
2317 {
2318 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2319 last_talked = TIME;
2320 }
2321 return 1;
2322 }
2323
2324 return 0;
2325 }
2326
2327 static fd_set readset;
2328 static int readset_n = 0;
2329
2330 // main loop - gets packets on tun or udp and processes them
2331 static void mainloop(void)
2332 {
2333 int i;
2334 uint8_t buf[65536];
2335 struct timeval to;
2336 clockt next_cluster_ping = 0; // send initial ping immediately
2337 time_t next_clean = time_now + config->cleanup_interval;
2338
2339 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2340 udpfd, tunfd, cluster_sockfd, controlfd);
2341
2342 FD_ZERO(&readset);
2343 FD_SET(udpfd, &readset);
2344 FD_SET(tunfd, &readset);
2345 FD_SET(controlfd, &readset);
2346 FD_SET(clifd, &readset);
2347 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2348 readset_n = udpfd;
2349 if (tunfd > readset_n) readset_n = tunfd;
2350 if (controlfd > readset_n) readset_n = controlfd;
2351 if (clifd > readset_n) readset_n = clifd;
2352 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2353
2354 while (!main_quit || still_busy())
2355 {
2356 fd_set r;
2357 int n = readset_n;
2358 #ifdef BGP
2359 fd_set w;
2360 int bgp_set[BGP_NUM_PEERS];
2361 #endif /* BGP */
2362
2363 if (config->reload_config)
2364 {
2365 // Update the config state based on config settings
2366 update_config();
2367 }
2368
2369 memcpy(&r, &readset, sizeof(fd_set));
2370 to.tv_sec = 0;
2371 to.tv_usec = 100000; // 1/10th of a second.
2372
2373 #ifdef BGP
2374 FD_ZERO(&w);
2375 for (i = 0; i < BGP_NUM_PEERS; i++)
2376 {
2377 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2378 if (bgp_set[i] & 1)
2379 {
2380 FD_SET(bgp_peers[i].sock, &r);
2381 if (bgp_peers[i].sock > n)
2382 n = bgp_peers[i].sock;
2383 }
2384
2385 if (bgp_set[i] & 2)
2386 {
2387 FD_SET(bgp_peers[i].sock, &w);
2388 if (bgp_peers[i].sock > n)
2389 n = bgp_peers[i].sock;
2390 }
2391 }
2392
2393 n = select(n + 1, &r, &w, 0, &to);
2394 #else /* BGP */
2395 n = select(n + 1, &r, 0, 0, &to);
2396 #endif /* BGP */
2397
2398 STAT(select_called);
2399
2400 TIME = now();
2401 if (n < 0)
2402 {
2403 if (errno == EINTR ||
2404 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2405 continue;
2406
2407 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2408 main_quit++;
2409 break;
2410 }
2411 else if (n)
2412 {
2413 struct sockaddr_in addr;
2414 int alen, c, s;
2415 int udp_pkts = 0;
2416 int tun_pkts = 0;
2417 int cluster_pkts = 0;
2418
2419 // nsctl commands
2420 if (FD_ISSET(controlfd, &r))
2421 {
2422 alen = sizeof(addr);
2423 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2424 n--;
2425 }
2426
2427 // RADIUS responses
2428 if (config->cluster_iam_master)
2429 {
2430 for (i = 0; i < config->num_radfds; i++)
2431 {
2432 if (FD_ISSET(radfds[i], &r))
2433 {
2434 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2435 n--;
2436 }
2437 }
2438 }
2439
2440 // CLI connections
2441 if (FD_ISSET(clifd, &r))
2442 {
2443 int cli;
2444
2445 alen = sizeof(addr);
2446 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
2447 {
2448 cli_do(cli);
2449 close(cli);
2450 }
2451 else
2452 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
2453
2454 n--;
2455 }
2456
2457 #ifdef BGP
2458 for (i = 0; i < BGP_NUM_PEERS; i++)
2459 {
2460 int isr = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0;
2461 int isw = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0;
2462 bgp_process(&bgp_peers[i], isr, isw);
2463 if (isr) n--;
2464 if (isw) n--;
2465 }
2466 #endif /* BGP */
2467
2468 for (c = 0; n && c < config->multi_read_count; c++)
2469 {
2470 // L2TP
2471 if (FD_ISSET(udpfd, &r))
2472 {
2473 alen = sizeof(addr);
2474 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2475 {
2476 processudp(buf, s, &addr);
2477 udp_pkts++;
2478 }
2479 else
2480 {
2481 FD_CLR(udpfd, &r);
2482 n--;
2483 }
2484 }
2485
2486 // incoming IP
2487 if (FD_ISSET(tunfd, &r))
2488 {
2489 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
2490 {
2491 processtun(buf, s);
2492 tun_pkts++;
2493 }
2494 else
2495 {
2496 FD_CLR(tunfd, &r);
2497 n--;
2498 }
2499 }
2500
2501 // cluster
2502 if (FD_ISSET(cluster_sockfd, &r))
2503 {
2504 alen = sizeof(addr);
2505 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
2506 {
2507 processcluster(buf, s, addr.sin_addr.s_addr);
2508 cluster_pkts++;
2509 }
2510 else
2511 {
2512 FD_CLR(cluster_sockfd, &r);
2513 n--;
2514 }
2515 }
2516 }
2517
2518 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
2519 STAT(multi_read_used);
2520
2521 if (c >= config->multi_read_count)
2522 {
2523 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
2524 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
2525
2526 STAT(multi_read_exceeded);
2527 }
2528 }
2529
2530 // Runs on every machine (master and slaves).
2531 if (cluster_sockfd && next_cluster_ping <= TIME)
2532 {
2533 // Check to see which of the cluster is still alive..
2534
2535 cluster_send_ping(basetime); // Only does anything if we're a slave
2536 cluster_check_master(); // ditto.
2537
2538 cluster_heartbeat(); // Only does anything if we're a master.
2539 cluster_check_slaves(); // ditto.
2540
2541 master_update_counts(); // If we're a slave, send our byte counters to our master.
2542
2543 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2544 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2545 else
2546 next_cluster_ping = TIME + config->cluster_hb_interval;
2547 }
2548
2549 // Run token bucket filtering queue..
2550 // Only run it every 1/10th of a second.
2551 // Runs on all machines both master and slave.
2552 {
2553 static clockt last_run = 0;
2554 if (last_run != TIME)
2555 {
2556 last_run = TIME;
2557 tbf_run_timer();
2558 }
2559 }
2560
2561 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2562 * something to read, else under load this will never actually run....
2563 *
2564 */
2565 if (config->cluster_iam_master && next_clean <= time_now)
2566 {
2567 if (regular_cleanups())
2568 {
2569 // Did it finish?
2570 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2571 }
2572 else
2573 {
2574 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2575 }
2576 }
2577 }
2578
2579 // Are we the master and shutting down??
2580 if (config->cluster_iam_master)
2581 cluster_heartbeat(); // Flush any queued changes..
2582
2583 // Ok. Notify everyone we're shutting down. If we're
2584 // the master, this will force an election.
2585 cluster_send_ping(0);
2586
2587 //
2588 // Important!!! We MUST not process any packets past this point!
2589 }
2590
2591 static void stripdomain(char *host)
2592 {
2593 char *p;
2594
2595 if ((p = strchr(host, '.')))
2596 {
2597 char *domain = 0;
2598 char _domain[1024];
2599
2600 // strip off domain
2601 FILE *resolv = fopen("/etc/resolv.conf", "r");
2602 if (resolv)
2603 {
2604 char buf[1024];
2605 char *b;
2606
2607 while (fgets(buf, sizeof(buf), resolv))
2608 {
2609 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
2610 continue;
2611
2612 if (!isspace(buf[6]))
2613 continue;
2614
2615 b = buf + 7;
2616 while (isspace(*b)) b++;
2617
2618 if (*b)
2619 {
2620 char *d = b;
2621 while (*b && !isspace(*b)) b++;
2622 *b = 0;
2623 if (buf[0] == 'd') // domain is canonical
2624 {
2625 domain = d;
2626 break;
2627 }
2628
2629 // first search line
2630 if (!domain)
2631 {
2632 // hold, may be subsequent domain line
2633 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
2634 domain = _domain;
2635 }
2636 }
2637 }
2638
2639 fclose(resolv);
2640 }
2641
2642 if (domain)
2643 {
2644 int hl = strlen(host);
2645 int dl = strlen(domain);
2646 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
2647 host[hl -dl - 1] = 0;
2648 }
2649 else
2650 {
2651 *p = 0; // everything after first dot
2652 }
2653 }
2654 }
2655
2656 // Init data structures
2657 static void initdata(int optdebug, char *optconfig)
2658 {
2659 int i;
2660
2661 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
2662 {
2663 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
2664 exit(1);
2665 }
2666 if (!(config = shared_malloc(sizeof(configt))))
2667 {
2668 LOG(0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
2669 exit(1);
2670 }
2671 memset(config, 0, sizeof(configt));
2672 time(&config->start_time);
2673 strncpy(config->config_file, optconfig, strlen(optconfig));
2674 config->debug = optdebug;
2675 config->num_tbfs = MAXTBFS;
2676 config->rl_rate = 28; // 28kbps
2677
2678 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
2679 {
2680 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
2681 exit(1);
2682 }
2683 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
2684 {
2685 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
2686 exit(1);
2687 }
2688
2689 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
2690 {
2691 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
2692 exit(1);
2693 }
2694
2695 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
2696 {
2697 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
2698 exit(1);
2699 }
2700
2701 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
2702 {
2703 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
2704 exit(1);
2705 }
2706
2707 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
2708 {
2709 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
2710 exit(1);
2711 }
2712 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
2713
2714 #ifdef RINGBUFFER
2715 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
2716 {
2717 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
2718 exit(1);
2719 }
2720 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2721 #endif
2722
2723 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
2724 {
2725 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
2726 exit(1);
2727 }
2728 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2729
2730 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
2731 {
2732 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
2733 exit(1);
2734 }
2735 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2736
2737 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2738 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2739 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2740 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2741
2742 // Put all the sessions on the free list marked as undefined.
2743 for (i = 1; i < MAXSESSION; i++)
2744 {
2745 session[i].next = i + 1;
2746 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2747 }
2748 session[MAXSESSION - 1].next = 0;
2749 sessionfree = 1;
2750
2751 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2752 for (i = 1; i < MAXTUNNEL; i++)
2753 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2754
2755 if (!*hostname)
2756 {
2757 // Grab my hostname unless it's been specified
2758 gethostname(hostname, sizeof(hostname));
2759 stripdomain(hostname);
2760 }
2761
2762 _statistics->start_time = _statistics->last_reset = time(NULL);
2763
2764 #ifdef BGP
2765 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
2766 {
2767 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
2768 exit(1);
2769 }
2770 #endif /* BGP */
2771 }
2772
2773 static int assign_ip_address(sessionidt s)
2774 {
2775 uint32_t i;
2776 int best = -1;
2777 time_t best_time = time_now;
2778 char *u = session[s].user;
2779 char reuse = 0;
2780
2781
2782 CSTAT(call_assign_ip_address);
2783
2784 for (i = 1; i < ip_pool_size; i++)
2785 {
2786 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2787 continue;
2788
2789 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2790 {
2791 best = i;
2792 reuse = 1;
2793 break;
2794 }
2795
2796 if (ip_address_pool[i].last < best_time)
2797 {
2798 best = i;
2799 if (!(best_time = ip_address_pool[i].last))
2800 break; // never used, grab this one
2801 }
2802 }
2803
2804 if (best < 0)
2805 {
2806 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2807 return 0;
2808 }
2809
2810 session[s].ip = ip_address_pool[best].address;
2811 session[s].ip_pool_index = best;
2812 ip_address_pool[best].assigned = 1;
2813 ip_address_pool[best].last = time_now;
2814 ip_address_pool[best].session = s;
2815 if (session[s].walled_garden)
2816 /* Don't track addresses of users in walled garden (note: this
2817 means that their address isn't "sticky" even if they get
2818 un-gardened). */
2819 ip_address_pool[best].user[0] = 0;
2820 else
2821 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2822
2823 STAT(ip_allocated);
2824 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
2825 reuse ? "Reusing" : "Allocating", best);
2826
2827 return 1;
2828 }
2829
2830 static void free_ip_address(sessionidt s)
2831 {
2832 int i = session[s].ip_pool_index;
2833
2834
2835 CSTAT(call_free_ip_address);
2836
2837 if (!session[s].ip)
2838 return; // what the?
2839
2840 if (i < 0) // Is this actually part of the ip pool?
2841 i = 0;
2842
2843 STAT(ip_freed);
2844 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2845 session[s].ip = 0;
2846 ip_address_pool[i].assigned = 0;
2847 ip_address_pool[i].session = 0;
2848 ip_address_pool[i].last = time_now;
2849 }
2850
2851 //
2852 // Fsck the address pool against the session table.
2853 // Normally only called when we become a master.
2854 //
2855 // This isn't perfect: We aren't keep tracking of which
2856 // users used to have an IP address.
2857 //
2858 void rebuild_address_pool(void)
2859 {
2860 int i;
2861
2862 //
2863 // Zero the IP pool allocation, and build
2864 // a map from IP address to pool index.
2865 for (i = 1; i < MAXIPPOOL; ++i)
2866 {
2867 ip_address_pool[i].assigned = 0;
2868 ip_address_pool[i].session = 0;
2869 if (!ip_address_pool[i].address)
2870 continue;
2871
2872 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2873 }
2874
2875 for (i = 0; i < MAXSESSION; ++i)
2876 {
2877 int ipid;
2878 if (!(session[i].opened && session[i].ip))
2879 continue;
2880 ipid = - lookup_ipmap(htonl(session[i].ip));
2881
2882 if (session[i].ip_pool_index < 0)
2883 {
2884 // Not allocated out of the pool.
2885 if (ipid < 1) // Not found in the pool either? good.
2886 continue;
2887
2888 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2889 i, fmtaddr(session[i].ip, 0), ipid);
2890
2891 // Fall through and process it as part of the pool.
2892 }
2893
2894
2895 if (ipid > MAXIPPOOL || ipid < 0)
2896 {
2897 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2898 ipid = -1;
2899 session[i].ip_pool_index = ipid;
2900 continue;
2901 }
2902
2903 ip_address_pool[ipid].assigned = 1;
2904 ip_address_pool[ipid].session = i;
2905 ip_address_pool[ipid].last = time_now;
2906 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2907 session[i].ip_pool_index = ipid;
2908 cache_ipmap(session[i].ip, i); // Fix the ip map.
2909 }
2910 }
2911
2912 //
2913 // Fix the address pool to match a changed session.
2914 // (usually when the master sends us an update).
2915 static void fix_address_pool(int sid)
2916 {
2917 int ipid;
2918
2919 ipid = session[sid].ip_pool_index;
2920
2921 if (ipid > ip_pool_size)
2922 return; // Ignore it. rebuild_address_pool will fix it up.
2923
2924 if (ip_address_pool[ipid].address != session[sid].ip)
2925 return; // Just ignore it. rebuild_address_pool will take care of it.
2926
2927 ip_address_pool[ipid].assigned = 1;
2928 ip_address_pool[ipid].session = sid;
2929 ip_address_pool[ipid].last = time_now;
2930 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2931 }
2932
2933 //
2934 // Add a block of addresses to the IP pool to hand out.
2935 //
2936 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
2937 {
2938 int i;
2939 if (mask == 0)
2940 mask = 0xffffffff; // Host route only.
2941
2942 addr &= mask;
2943
2944 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2945 return ;
2946
2947 for (i = addr ;(i & mask) == addr; ++i)
2948 {
2949 if ((i & 0xff) == 0 || (i&0xff) == 255)
2950 continue; // Skip 0 and broadcast addresses.
2951
2952 ip_address_pool[ip_pool_size].address = i;
2953 ip_address_pool[ip_pool_size].assigned = 0;
2954 ++ip_pool_size;
2955 if (ip_pool_size >= MAXIPPOOL)
2956 {
2957 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
2958 return;
2959 }
2960 }
2961 }
2962
2963 // Initialize the IP address pool
2964 static void initippool()
2965 {
2966 FILE *f;
2967 char *p;
2968 char buf[4096];
2969 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2970
2971 if (!(f = fopen(IPPOOLFILE, "r")))
2972 {
2973 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2974 exit(1);
2975 }
2976
2977 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2978 {
2979 char *pool = buf;
2980 buf[4095] = 0; // Force it to be zero terminated/
2981
2982 if (*buf == '#' || *buf == '\n')
2983 continue; // Skip comments / blank lines
2984 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2985 if ((p = (char *)strchr(buf, ':')))
2986 {
2987 in_addr_t src;
2988 *p = '\0';
2989 src = inet_addr(buf);
2990 if (src == INADDR_NONE)
2991 {
2992 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
2993 exit(1);
2994 }
2995 // This entry is for a specific IP only
2996 if (src != config->bind_address)
2997 continue;
2998 *p = ':';
2999 pool = p+1;
3000 }
3001 if ((p = (char *)strchr(pool, '/')))
3002 {
3003 // It's a range
3004 int numbits = 0;
3005 in_addr_t start = 0, mask = 0;
3006
3007 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3008 *p++ = 0;
3009 if (!*p || !(numbits = atoi(p)))
3010 {
3011 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3012 continue;
3013 }
3014 start = ntohl(inet_addr(pool));
3015 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3016
3017 // Add a static route for this pool
3018 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3019 fmtaddr(htonl(start), 0), 32 + mask);
3020
3021 routeset(0, start, mask, 0, 1);
3022
3023 add_to_ip_pool(start, mask);
3024 }
3025 else
3026 {
3027 // It's a single ip address
3028 add_to_ip_pool(inet_addr(pool), 0);
3029 }
3030 }
3031 fclose(f);
3032 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3033 }
3034
3035 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3036 {
3037 struct sockaddr_in snoop_addr = {0};
3038 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3039 return;
3040
3041 snoop_addr.sin_family = AF_INET;
3042 snoop_addr.sin_addr.s_addr = destination;
3043 snoop_addr.sin_port = ntohs(port);
3044
3045 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3046 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3047 htons(snoop_addr.sin_port));
3048
3049 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3050 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3051
3052 STAT(packets_snooped);
3053 }
3054
3055 static int dump_session(FILE **f, sessiont *s)
3056 {
3057 if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
3058 return 1;
3059
3060 if (!*f)
3061 {
3062 char filename[1024];
3063 char timestr[64];
3064 time_t now = time(NULL);
3065
3066 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3067 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3068
3069 if (!(*f = fopen(filename, "w")))
3070 {
3071 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3072 return 0;
3073 }
3074
3075 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3076 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3077 "# host: %s\n"
3078 "# time: %ld\n"
3079 "# uptime: %ld\n"
3080 "# format: username ip qos uptxoctets downrxoctets\n",
3081 hostname,
3082 now,
3083 now - basetime);
3084 }
3085
3086 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3087 fprintf(*f, "%s %s %d %u %u\n",
3088 s->user, // username
3089 fmtaddr(htonl(s->ip), 0), // ip
3090 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3091 (uint32_t) s->cin, // uptxoctets
3092 (uint32_t) s->cout); // downrxoctets
3093
3094 s->pin = s->cin = 0;
3095 s->pout = s->cout = 0;
3096
3097 return 1;
3098 }
3099
3100 static void dump_acct_info(int all)
3101 {
3102 int i;
3103 FILE *f = NULL;
3104
3105
3106 CSTAT(call_dump_acct_info);
3107
3108 if (shut_acct_n)
3109 {
3110 for (i = 0; i < shut_acct_n; i++)
3111 dump_session(&f, &shut_acct[i]);
3112
3113 shut_acct_n = 0;
3114 }
3115
3116 if (all)
3117 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3118 dump_session(&f, &session[i]);
3119
3120 if (f)
3121 fclose(f);
3122 }
3123
3124 // Main program
3125 int main(int argc, char *argv[])
3126 {
3127 int i;
3128 int optdebug = 0;
3129 char *optconfig = CONFIGFILE;
3130
3131 time(&basetime); // start clock
3132
3133 // scan args
3134 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3135 {
3136 switch (i)
3137 {
3138 case 'd':
3139 if (fork()) exit(0);
3140 setsid();
3141 freopen("/dev/null", "r", stdin);
3142 freopen("/dev/null", "w", stdout);
3143 freopen("/dev/null", "w", stderr);
3144 break;
3145 case 'v':
3146 optdebug++;
3147 break;
3148 case 'c':
3149 optconfig = optarg;
3150 break;
3151 case 'h':
3152 snprintf(hostname, sizeof(hostname), "%s", optarg);
3153 break;
3154 default:
3155 printf("Args are:\n"
3156 "\t-d\t\tDetach from terminal\n"
3157 "\t-c <file>\tConfig file\n"
3158 "\t-h <hostname>\tForce hostname\n"
3159 "\t-v\t\tDebug\n");
3160
3161 return (0);
3162 break;
3163 }
3164 }
3165
3166 // Start the timer routine off
3167 time(&time_now);
3168 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3169 signal(SIGALRM, sigalrm_handler);
3170 siginterrupt(SIGALRM, 0);
3171
3172 initplugins();
3173 initdata(optdebug, optconfig);
3174
3175 init_cli(hostname);
3176 read_config_file();
3177 init_tbf(config->num_tbfs);
3178
3179 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3180 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3181 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3182 {
3183 struct rlimit rlim;
3184 rlim.rlim_cur = RLIM_INFINITY;
3185 rlim.rlim_max = RLIM_INFINITY;
3186 // Remove the maximum core size
3187 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3188 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3189
3190 // Make core dumps go to /tmp
3191 chdir("/tmp");
3192 }
3193
3194 if (config->scheduler_fifo)
3195 {
3196 int ret;
3197 struct sched_param params = {0};
3198 params.sched_priority = 1;
3199
3200 if (get_nprocs() < 2)
3201 {
3202 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3203 config->scheduler_fifo = 0;
3204 }
3205 else
3206 {
3207 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3208 {
3209 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3210 }
3211 else
3212 {
3213 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3214 config->scheduler_fifo = 0;
3215 }
3216 }
3217 }
3218
3219 /* Set up the cluster communications port. */
3220 if (cluster_init() < 0)
3221 exit(1);
3222
3223 #ifdef BGP
3224 signal(SIGPIPE, SIG_IGN);
3225 bgp_setup(config->as_number);
3226 bgp_add_route(config->bind_address, 0xffffffff);
3227 for (i = 0; i < BGP_NUM_PEERS; i++)
3228 {
3229 if (config->neighbour[i].name[0])
3230 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3231 config->neighbour[i].as, config->neighbour[i].keepalive,
3232 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3233 }
3234 #endif /* BGP */
3235
3236 inittun();
3237 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3238
3239 initudp();
3240 initrad();
3241 initippool();
3242
3243 read_state();
3244
3245 signal(SIGHUP, sighup_handler);
3246 signal(SIGTERM, sigterm_handler);
3247 signal(SIGINT, sigterm_handler);
3248 signal(SIGQUIT, sigquit_handler);
3249 signal(SIGCHLD, sigchild_handler);
3250
3251 // Prevent us from getting paged out
3252 if (config->lock_pages)
3253 {
3254 if (!mlockall(MCL_CURRENT))
3255 LOG(1, 0, 0, "Locking pages into memory\n");
3256 else
3257 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3258 }
3259
3260 alarm(1);
3261
3262 // Drop privileges here
3263 if (config->target_uid > 0 && geteuid() == 0)
3264 setuid(config->target_uid);
3265
3266 mainloop();
3267
3268 #ifdef BGP
3269 /* try to shut BGP down cleanly; with luck the sockets will be
3270 writable since we're out of the select */
3271 for (i = 0; i < BGP_NUM_PEERS; i++)
3272 if (bgp_peers[i].state == Established)
3273 bgp_stop(&bgp_peers[i]);
3274 #endif /* BGP */
3275
3276 /* remove plugins (so cleanup code gets run) */
3277 plugins_done();
3278
3279 // Remove the PID file if we wrote it
3280 if (config->wrote_pid && *config->pid_file == '/')
3281 unlink(config->pid_file);
3282
3283 /* kill CLI children */
3284 signal(SIGTERM, SIG_IGN);
3285 kill(0, SIGTERM);
3286 return 0;
3287 }
3288
3289 static void sighup_handler(int sig)
3290 {
3291 if (log_stream && log_stream != stderr)
3292 {
3293 fclose(log_stream);
3294 log_stream = NULL;
3295 }
3296
3297 read_config_file();
3298 }
3299
3300 static void sigalrm_handler(int sig)
3301 {
3302 // Log current traffic stats
3303
3304 snprintf(config->bandwidth, sizeof(config->bandwidth),
3305 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3306 (udp_rx / 1024.0 / 1024.0 * 8),
3307 (eth_tx / 1024.0 / 1024.0 * 8),
3308 (eth_rx / 1024.0 / 1024.0 * 8),
3309 (udp_tx / 1024.0 / 1024.0 * 8),
3310 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3311 udp_rx_pkt, eth_rx_pkt);
3312
3313 udp_tx = udp_rx = 0;
3314 udp_rx_pkt = eth_rx_pkt = 0;
3315 eth_tx = eth_rx = 0;
3316
3317 if (config->dump_speed)
3318 printf("%s\n", config->bandwidth);
3319
3320 // Update the internal time counter
3321 time(&time_now);
3322 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3323 alarm(1);
3324
3325 {
3326 // Run timer hooks
3327 struct param_timer p = { time_now };
3328 run_plugins(PLUGIN_TIMER, &p);
3329 }
3330
3331 }
3332
3333 static void sigterm_handler(int sig)
3334 {
3335 LOG(1, 0, 0, "Shutting down cleanly\n");
3336 if (config->save_state)
3337 dump_state();
3338
3339 main_quit++;
3340 }
3341
3342 static void sigquit_handler(int sig)
3343 {
3344 int i;
3345
3346 LOG(1, 0, 0, "Shutting down without saving sessions\n");
3347
3348 if (config->cluster_iam_master)
3349 {
3350 for (i = 1; i < MAXSESSION; i++)
3351 {
3352 if (session[i].opened)
3353 sessionkill(i, "L2TPNS Closing");
3354 }
3355 for (i = 1; i < MAXTUNNEL; i++)
3356 {
3357 if (tunnel[i].ip || tunnel[i].state)
3358 tunnelshutdown(i, "L2TPNS Closing");
3359 }
3360 }
3361
3362 main_quit++;
3363 }
3364
3365 static void sigchild_handler(int sig)
3366 {
3367 while (waitpid(-1, NULL, WNOHANG) > 0)
3368 ;
3369 }
3370
3371 static void read_state()
3372 {
3373 struct stat sb;
3374 int i;
3375 ippoolt itmp;
3376 FILE *f;
3377 char magic[sizeof(DUMP_MAGIC) - 1];
3378 uint32_t buf[2];
3379
3380 if (!config->save_state)
3381 {
3382 unlink(STATEFILE);
3383 return ;
3384 }
3385
3386 if (stat(STATEFILE, &sb) < 0)
3387 {
3388 unlink(STATEFILE);
3389 return ;
3390 }
3391
3392 if (sb.st_mtime < (time(NULL) - 60))
3393 {
3394 LOG(0, 0, 0, "State file is too old to read, ignoring\n");
3395 unlink(STATEFILE);
3396 return ;
3397 }
3398
3399 f = fopen(STATEFILE, "r");
3400 unlink(STATEFILE);
3401
3402 if (!f)
3403 {
3404 LOG(0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3405 exit(1);
3406 }
3407
3408 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3409 {
3410 LOG(0, 0, 0, "Bad state file magic\n");
3411 exit(1);
3412 }
3413
3414 LOG(1, 0, 0, "Reading state information\n");
3415 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3416 {
3417 LOG(0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3418 exit(1);
3419 }
3420
3421 if (buf[0] > ip_pool_size)
3422 {
3423 LOG(0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3424 exit(1);
3425 }
3426
3427 LOG(2, 0, 0, "Loading %u ip addresses\n", buf[0]);
3428 for (i = 0; i < buf[0]; i++)
3429 {
3430 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3431 {
3432 LOG(0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3433 exit(1);
3434 }
3435
3436 if (itmp.address != ip_address_pool[i].address)
3437 {
3438 LOG(0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3439 exit(1);
3440 }
3441
3442 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3443 }
3444
3445 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3446 {
3447 LOG(0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3448 exit(1);
3449 }
3450
3451 LOG(2, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3452 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3453 {
3454 LOG(0, 0, 0, "Error reading tunnel data from state file\n");
3455 exit(1);
3456 }
3457
3458 for (i = 0; i < MAXTUNNEL; i++)
3459 {
3460 tunnel[i].controlc = 0;
3461 tunnel[i].controls = NULL;
3462 tunnel[i].controle = NULL;
3463 if (*tunnel[i].hostname)
3464 LOG(3, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3465 }
3466
3467 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3468 {
3469 LOG(0, 0, 0, "Error/mismatch reading session header from state file\n");
3470 exit(1);
3471 }
3472
3473 LOG(2, 0, 0, "Loading %u sessions\n", MAXSESSION);
3474 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3475 {
3476 LOG(0, 0, 0, "Error reading session data from state file\n");
3477 exit(1);
3478 }
3479
3480 for (i = 0; i < MAXSESSION; i++)
3481 {
3482 session[i].tbf_in = 0;
3483 session[i].tbf_out = 0;
3484 if (session[i].opened)
3485 {
3486 LOG(2, i, 0, "Loaded active session for user %s\n", session[i].user);
3487 if (session[i].ip)
3488 sessionsetup(session[i].tunnel, i);
3489 }
3490 }
3491
3492 fclose(f);
3493 LOG(0, 0, 0, "Loaded saved state information\n");
3494 }
3495
3496 static void dump_state()
3497 {
3498 FILE *f;
3499 uint32_t buf[2];
3500
3501 if (!config->save_state)
3502 return;
3503
3504 do
3505 {
3506 if (!(f = fopen(STATEFILE, "w")))
3507 break;
3508
3509 LOG(1, 0, 0, "Dumping state information\n");
3510
3511 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
3512 break;
3513
3514 LOG(2, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3515 buf[0] = ip_pool_size;
3516 buf[1] = sizeof(ippoolt);
3517 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3518 break;
3519 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
3520 break;
3521
3522 LOG(2, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3523 buf[0] = MAXTUNNEL;
3524 buf[1] = sizeof(tunnelt);
3525 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3526 break;
3527 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3528 break;
3529
3530 LOG(2, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3531 buf[0] = MAXSESSION;
3532 buf[1] = sizeof(sessiont);
3533 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3534 break;
3535 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3536 break;
3537
3538 if (fclose(f) == 0)
3539 return ; // OK
3540 }
3541 while (0);
3542
3543 LOG(0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3544 unlink(STATEFILE);
3545 }
3546
3547 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
3548 {
3549 MD5_CTX ctx;
3550 *challenge_response = NULL;
3551
3552 if (!*config->l2tpsecret)
3553 {
3554 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3555 return;
3556 }
3557
3558 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
3559
3560 *challenge_response = (char *)calloc(17, 1);
3561
3562 MD5Init(&ctx);
3563 MD5Update(&ctx, &id, 1);
3564 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3565 MD5Update(&ctx, challenge, challenge_length);
3566 MD5Final(*challenge_response, &ctx);
3567
3568 return;
3569 }
3570
3571 static int facility_value(char *name)
3572 {
3573 int i;
3574 for (i = 0; facilitynames[i].c_name; i++)
3575 {
3576 if (strcmp(facilitynames[i].c_name, name) == 0)
3577 return facilitynames[i].c_val;
3578 }
3579 return 0;
3580 }
3581
3582 static void update_config()
3583 {
3584 int i;
3585 static int timeout = 0;
3586 static int interval = 0;
3587
3588 // Update logging
3589 closelog();
3590 syslog_log = 0;
3591 if (log_stream)
3592 {
3593 fclose(log_stream);
3594 log_stream = NULL;
3595 }
3596 if (*config->log_filename)
3597 {
3598 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3599 {
3600 char *p = config->log_filename + 7;
3601 if (*p)
3602 {
3603 openlog("l2tpns", LOG_PID, facility_value(p));
3604 syslog_log = 1;
3605 }
3606 }
3607 else if (strchr(config->log_filename, '/') == config->log_filename)
3608 {
3609 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3610 {
3611 fseek(log_stream, 0, SEEK_END);
3612 setbuf(log_stream, NULL);
3613 }
3614 else
3615 {
3616 log_stream = stderr;
3617 setbuf(log_stream, NULL);
3618 }
3619 }
3620 }
3621 else
3622 {
3623 log_stream = stderr;
3624 setbuf(log_stream, NULL);
3625 }
3626
3627
3628 // Update radius
3629 config->numradiusservers = 0;
3630 for (i = 0; i < MAXRADSERVER; i++)
3631 if (config->radiusserver[i])
3632 {
3633 config->numradiusservers++;
3634 // Set radius port: if not set, take the port from the
3635 // first radius server. For the first radius server,
3636 // take the #defined default value from l2tpns.h
3637
3638 // test twice, In case someone works with
3639 // a secondary radius server without defining
3640 // a primary one, this will work even then.
3641 if (i>0 && !config->radiusport[i])
3642 config->radiusport[i] = config->radiusport[i-1];
3643 if (!config->radiusport[i])
3644 config->radiusport[i] = RADPORT;
3645 }
3646
3647 if (!config->numradiusservers)
3648 LOG(0, 0, 0, "No RADIUS servers defined!\n");
3649
3650 config->num_radfds = 2 << RADIUS_SHIFT;
3651
3652 // Update plugins
3653 for (i = 0; i < MAXPLUGINS; i++)
3654 {
3655 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3656 continue;
3657
3658 if (*config->plugins[i])
3659 {
3660 // Plugin added
3661 add_plugin(config->plugins[i]);
3662 }
3663 else if (*config->old_plugins[i])
3664 {
3665 // Plugin removed
3666 remove_plugin(config->old_plugins[i]);
3667 }
3668 }
3669 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3670 if (!config->cleanup_interval) config->cleanup_interval = 10;
3671 if (!config->multi_read_count) config->multi_read_count = 10;
3672 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3673 if (!*config->cluster_interface)
3674 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3675
3676 if (!config->cluster_hb_interval)
3677 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3678
3679 if (!config->cluster_hb_timeout)
3680 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3681
3682 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3683 {
3684 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3685 // late, ensure we're sufficiently larger than that
3686 int t = 4 * config->cluster_hb_interval + 11;
3687
3688 if (config->cluster_hb_timeout < t)
3689 {
3690 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3691 config->cluster_hb_timeout = t;
3692 }
3693
3694 // Push timing changes to the slaves immediately if we're the master
3695 if (config->cluster_iam_master)
3696 cluster_heartbeat();
3697
3698 interval = config->cluster_hb_interval;
3699 timeout = config->cluster_hb_timeout;
3700 }
3701
3702 // Write PID file
3703 if (*config->pid_file == '/' && !config->wrote_pid)
3704 {
3705 FILE *f;
3706 if ((f = fopen(config->pid_file, "w")))
3707 {
3708 fprintf(f, "%d\n", getpid());
3709 fclose(f);
3710 config->wrote_pid = 1;
3711 }
3712 else
3713 {
3714 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3715 }
3716 }
3717
3718 config->reload_config = 0;
3719 }
3720
3721 static void read_config_file()
3722 {
3723 FILE *f;
3724
3725 if (!config->config_file) return;
3726 if (!(f = fopen(config->config_file, "r")))
3727 {
3728 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3729 return;
3730 }
3731
3732 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
3733 cli_do_file(f);
3734 LOG(3, 0, 0, "Done reading config file\n");
3735 fclose(f);
3736 update_config();
3737 }
3738
3739 int sessionsetup(tunnelidt t, sessionidt s)
3740 {
3741 // A session now exists, set it up
3742 in_addr_t ip;
3743 char *user;
3744 sessionidt i;
3745 int r;
3746
3747 CSTAT(call_sessionsetup);
3748
3749 LOG(3, s, t, "Doing session setup for session\n");
3750
3751 if (!session[s].ip)
3752 {
3753 assign_ip_address(s);
3754 if (!session[s].ip)
3755 {
3756 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3757 sessionshutdown(s, "No IP addresses available");
3758 return 0;
3759 }
3760 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
3761 fmtaddr(htonl(session[s].ip), 0));
3762 }
3763
3764
3765 // Make sure this is right
3766 session[s].tunnel = t;
3767
3768 // zap old sessions with same IP and/or username
3769 // Don't kill gardened sessions - doing so leads to a DoS
3770 // from someone who doesn't need to know the password
3771 {
3772 ip = session[s].ip;
3773 user = session[s].user;
3774 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3775 {
3776 if (i == s) continue;
3777 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3778 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3779 sessionkill(i, "Duplicate session for users");
3780 }
3781 }
3782
3783 {
3784 int routed = 0;
3785
3786 // Add the route for this session.
3787 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3788 {
3789 if ((session[s].ip & session[s].route[r].mask) ==
3790 (session[s].route[r].ip & session[s].route[r].mask))
3791 routed++;
3792
3793 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
3794 }
3795
3796 // Static IPs need to be routed if not already
3797 // convered by a Framed-Route. Anything else is part
3798 // of the IP address pool and is already routed, it
3799 // just needs to be added to the IP cache.
3800 if (session[s].ip_pool_index == -1) // static ip
3801 {
3802 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
3803 }
3804 else
3805 cache_ipmap(session[s].ip, s);
3806 }
3807
3808 if (!session[s].unique_id)
3809 {
3810 // did this session just finish radius?
3811 LOG(3, s, t, "Sending initial IPCP to client\n");
3812 sendipcp(t, s);
3813 session[s].unique_id = ++last_id;
3814 }
3815
3816 // Run the plugin's against this new session.
3817 {
3818 struct param_new_session data = { &tunnel[t], &session[s] };
3819 run_plugins(PLUGIN_NEW_SESSION, &data);
3820 }
3821
3822 // Allocate TBFs if throttled
3823 if (session[s].throttle_in || session[s].throttle_out)
3824 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
3825
3826 session[s].last_packet = time_now;
3827
3828 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
3829 fmtaddr(htonl(session[s].ip), 0),
3830 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
3831
3832 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3833
3834 return 1; // RADIUS OK and IP allocated, done...
3835 }
3836
3837 //
3838 // This session just got dropped on us by the master or something.
3839 // Make sure our tables up up to date...
3840 //
3841 int load_session(sessionidt s, sessiont *new)
3842 {
3843 int i;
3844 int newip = 0;
3845
3846 // Sanity checks.
3847 if (new->ip_pool_index >= MAXIPPOOL ||
3848 new->tunnel >= MAXTUNNEL)
3849 {
3850 LOG(0, s, 0, "Strange session update received!\n");
3851 // FIXME! What to do here?
3852 return 0;
3853 }
3854
3855 //
3856 // Ok. All sanity checks passed. Now we're committed to
3857 // loading the new session.
3858 //
3859
3860 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3861
3862 // See if routes/ip cache need updating
3863 if (new->ip != session[s].ip)
3864 newip++;
3865
3866 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3867 if (new->route[i].ip != session[s].route[i].ip ||
3868 new->route[i].mask != session[s].route[i].mask)
3869 newip++;
3870
3871 // needs update
3872 if (newip)
3873 {
3874 int routed = 0;
3875
3876 // remove old routes...
3877 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3878 {
3879 if ((session[s].ip & session[s].route[i].mask) ==
3880 (session[s].route[i].ip & session[s].route[i].mask))
3881 routed++;
3882
3883 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
3884 }
3885
3886 // ...ip
3887 if (session[s].ip)
3888 {
3889 if (session[s].ip_pool_index == -1) // static IP
3890 {
3891 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
3892 }
3893 else // It's part of the IP pool, remove it manually.
3894 uncache_ipmap(session[s].ip);
3895 }
3896
3897 routed = 0;
3898
3899 // add new routes...
3900 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
3901 {
3902 if ((new->ip & new->route[i].mask) ==
3903 (new->route[i].ip & new->route[i].mask))
3904 routed++;
3905
3906 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
3907 }
3908
3909 // ...ip
3910 if (new->ip)
3911 {
3912 // If there's a new one, add it.
3913 if (new->ip_pool_index == -1)
3914 {
3915 if (!routed) routeset(s, new->ip, 0, 0, 1);
3916 }
3917 else
3918 cache_ipmap(new->ip, s);
3919 }
3920 }
3921
3922 // check filters
3923 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
3924 {
3925 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
3926 new->filter_in = 0;
3927 }
3928
3929 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
3930 {
3931 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
3932 new->filter_out = 0;
3933 }
3934
3935 if (new->filter_in != session[s].filter_in)
3936 {
3937 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
3938 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
3939 }
3940
3941 if (new->filter_out != session[s].filter_out)
3942 {
3943 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
3944 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
3945 }
3946
3947 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3948 // for walking the sessions to forward byte counts to the master.
3949 config->cluster_highest_sessionid = s;
3950
3951 // TEMP: old session struct used a uint32_t to define the throttle
3952 // speed for both up/down, new uses a uint16_t for each. Deal with
3953 // sessions from an old master for migration.
3954 if (new->throttle_out == 0 && new->tbf_out)
3955 new->throttle_out = new->throttle_in;
3956
3957 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3958
3959 // Do fixups into address pool.
3960 if (new->ip_pool_index != -1)
3961 fix_address_pool(s);
3962
3963 return 1;
3964 }
3965
3966 static void initplugins()
3967 {
3968 int i;
3969
3970 loaded_plugins = ll_init();
3971 // Initialize the plugins to nothing
3972 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3973 plugins[i] = ll_init();
3974 }
3975
3976 static void *open_plugin(char *plugin_name, int load)
3977 {
3978 char path[256] = "";
3979
3980 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3981 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3982 return dlopen(path, RTLD_NOW);
3983 }
3984
3985 // plugin callback to get a config value
3986 static void *getconfig(char *key, enum config_typet type)
3987 {
3988 int i;
3989
3990 for (i = 0; config_values[i].key; i++)
3991 {
3992 if (!strcmp(config_values[i].key, key))
3993 {
3994 if (config_values[i].type == type)
3995 return ((void *) config) + config_values[i].offset;
3996
3997 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
3998 key, type, config_values[i].type);
3999
4000 return 0;
4001 }
4002 }
4003
4004 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4005 return 0;
4006 }
4007
4008 static int add_plugin(char *plugin_name)
4009 {
4010 static struct pluginfuncs funcs = {
4011 _log,
4012 _log_hex,
4013 fmtaddr,
4014 sessionbyuser,
4015 sessiontbysessionidt,
4016 sessionidtbysessiont,
4017 radiusnew,
4018 radiussend,
4019 getconfig,
4020 sessionkill,
4021 throttle_session,
4022 cluster_send_session,
4023 };
4024
4025 void *p = open_plugin(plugin_name, 1);
4026 int (*initfunc)(struct pluginfuncs *);
4027 int i;
4028
4029 if (!p)
4030 {
4031 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4032 return -1;
4033 }
4034
4035 if (ll_contains(loaded_plugins, p))
4036 {
4037 dlclose(p);
4038 return 0; // already loaded
4039 }
4040
4041 {
4042 int *v = dlsym(p, "plugin_api_version");
4043 if (!v || *v != PLUGIN_API_VERSION)
4044 {
4045 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4046 dlclose(p);
4047 return -1;
4048 }
4049 }
4050
4051 if ((initfunc = dlsym(p, "plugin_init")))
4052 {
4053 if (!initfunc(&funcs))
4054 {
4055 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4056 dlclose(p);
4057 return -1;
4058 }
4059 }
4060
4061 ll_push(loaded_plugins, p);
4062
4063 for (i = 0; i < max_plugin_functions; i++)
4064 {
4065 void *x;
4066 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4067 {
4068 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4069 ll_push(plugins[i], x);
4070 }
4071 }
4072
4073 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4074 return 1;
4075 }
4076
4077 static void run_plugin_done(void *plugin)
4078 {
4079 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4080
4081 if (donefunc)
4082 donefunc();
4083 }
4084
4085 static int remove_plugin(char *plugin_name)
4086 {
4087 void *p = open_plugin(plugin_name, 0);
4088 int loaded = 0;
4089
4090 if (!p)
4091 return -1;
4092
4093 if (ll_contains(loaded_plugins, p))
4094 {
4095 int i;
4096 for (i = 0; i < max_plugin_functions; i++)
4097 {
4098 void *x;
4099 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4100 ll_delete(plugins[i], x);
4101 }
4102
4103 ll_delete(loaded_plugins, p);
4104 run_plugin_done(p);
4105 loaded = 1;
4106 }
4107
4108 dlclose(p);
4109 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4110 return loaded;
4111 }
4112
4113 int run_plugins(int plugin_type, void *data)
4114 {
4115 int (*func)(void *data);
4116
4117 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4118 return PLUGIN_RET_ERROR;
4119
4120 ll_reset(plugins[plugin_type]);
4121 while ((func = ll_next(plugins[plugin_type])))
4122 {
4123 int r = func(data);
4124
4125 if (r != PLUGIN_RET_OK)
4126 return r; // stop here
4127 }
4128
4129 return PLUGIN_RET_OK;
4130 }
4131
4132 static void plugins_done()
4133 {
4134 void *p;
4135
4136 ll_reset(loaded_plugins);
4137 while ((p = ll_next(loaded_plugins)))
4138 run_plugin_done(p);
4139 }
4140
4141 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4142 {
4143 struct nsctl request;
4144 struct nsctl response;
4145 int type = unpack_control(&request, buf, len);
4146 int r;
4147 void *p;
4148
4149 if (log_stream && config->debug >= 4)
4150 {
4151 if (type < 0)
4152 {
4153 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4154 fmtaddr(addr->sin_addr.s_addr, 0), type);
4155 }
4156 else
4157 {
4158 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4159 dump_control(&request, log_stream);
4160 }
4161 }
4162
4163 switch (type)
4164 {
4165 case NSCTL_REQ_LOAD:
4166 if (request.argc != 1)
4167 {
4168 response.type = NSCTL_RES_ERR;
4169 response.argc = 1;
4170 response.argv[0] = "name of plugin required";
4171 }
4172 else if ((r = add_plugin(request.argv[0])) < 1)
4173 {
4174 response.type = NSCTL_RES_ERR;
4175 response.argc = 1;
4176 response.argv[0] = !r
4177 ? "plugin already loaded"
4178 : "error loading plugin";
4179 }
4180 else
4181 {
4182 response.type = NSCTL_RES_OK;
4183 response.argc = 0;
4184 }
4185
4186 break;
4187
4188 case NSCTL_REQ_UNLOAD:
4189 if (request.argc != 1)
4190 {
4191 response.type = NSCTL_RES_ERR;
4192 response.argc = 1;
4193 response.argv[0] = "name of plugin required";
4194 }
4195 else if ((r = remove_plugin(request.argv[0])) < 1)
4196 {
4197 response.type = NSCTL_RES_ERR;
4198 response.argc = 1;
4199 response.argv[0] = !r
4200 ? "plugin not loaded"
4201 : "plugin not found";
4202 }
4203 else
4204 {
4205 response.type = NSCTL_RES_OK;
4206 response.argc = 0;
4207 }
4208
4209 break;
4210
4211 case NSCTL_REQ_HELP:
4212 response.type = NSCTL_RES_OK;
4213 response.argc = 0;
4214
4215 ll_reset(loaded_plugins);
4216 while ((p = ll_next(loaded_plugins)))
4217 {
4218 char **help = dlsym(p, "plugin_control_help");
4219 while (response.argc < 0xff && help && *help)
4220 response.argv[response.argc++] = *help++;
4221 }
4222
4223 break;
4224
4225 case NSCTL_REQ_CONTROL:
4226 {
4227 struct param_control param = {
4228 config->cluster_iam_master,
4229 request.argc,
4230 request.argv,
4231 0,
4232 NULL,
4233 };
4234
4235 int r = run_plugins(PLUGIN_CONTROL, &param);
4236
4237 if (r == PLUGIN_RET_ERROR)
4238 {
4239 response.type = NSCTL_RES_ERR;
4240 response.argc = 1;
4241 response.argv[0] = param.additional
4242 ? param.additional
4243 : "error returned by plugin";
4244 }
4245 else if (r == PLUGIN_RET_NOTMASTER)
4246 {
4247 static char msg[] = "must be run on master: 000.000.000.000";
4248
4249 response.type = NSCTL_RES_ERR;
4250 response.argc = 1;
4251 if (config->cluster_master_address)
4252 {
4253 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4254 response.argv[0] = msg;
4255 }
4256 else
4257 {
4258 response.argv[0] = "must be run on master: none elected";
4259 }
4260 }
4261 else if (!(param.response & NSCTL_RESPONSE))
4262 {
4263 response.type = NSCTL_RES_ERR;
4264 response.argc = 1;
4265 response.argv[0] = param.response
4266 ? "unrecognised response value from plugin"
4267 : "unhandled action";
4268 }
4269 else
4270 {
4271 response.type = param.response;
4272 response.argc = 0;
4273 if (param.additional)
4274 {
4275 response.argc = 1;
4276 response.argv[0] = param.additional;
4277 }
4278 }
4279 }
4280
4281 break;
4282
4283 default:
4284 response.type = NSCTL_RES_ERR;
4285 response.argc = 1;
4286 response.argv[0] = "error unpacking control packet";
4287 }
4288
4289 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4290 if (!buf)
4291 {
4292 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4293 return;
4294 }
4295
4296 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4297 if (r > 0)
4298 {
4299 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4300 if (log_stream && config->debug >= 4)
4301 {
4302 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4303 dump_control(&response, log_stream);
4304 }
4305 }
4306 else
4307 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4308 fmtaddr(addr->sin_addr.s_addr, 0), r);
4309
4310 free(buf);
4311 }
4312
4313 static tunnelidt new_tunnel()
4314 {
4315 tunnelidt i;
4316 for (i = 1; i < MAXTUNNEL; i++)
4317 {
4318 if (tunnel[i].state == TUNNELFREE)
4319 {
4320 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4321 if (i > config->cluster_highest_tunnelid)
4322 config->cluster_highest_tunnelid = i;
4323 return i;
4324 }
4325 }
4326 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4327 return 0;
4328 }
4329
4330 //
4331 // We're becoming the master. Do any required setup..
4332 //
4333 // This is principally telling all the plugins that we're
4334 // now a master, and telling them about all the sessions
4335 // that are active too..
4336 //
4337 void become_master(void)
4338 {
4339 int s, i;
4340 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4341
4342 // running a bunch of iptables commands is slow and can cause
4343 // the master to drop tunnels on takeover--kludge around the
4344 // problem by forking for the moment (note: race)
4345 if (!fork_and_close())
4346 {
4347 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4348 {
4349 if (!session[s].opened) // Not an in-use session.
4350 continue;
4351
4352 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4353 }
4354 exit(0);
4355 }
4356
4357 // add radius fds
4358 for (i = 0; i < config->num_radfds; i++)
4359 {
4360 FD_SET(radfds[i], &readset);
4361 if (radfds[i] > readset_n)
4362 readset_n = radfds[i];
4363 }
4364 }
4365
4366 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4367 {
4368 int s, i;
4369 int count = 0;
4370 int buckets[64];
4371
4372 if (CLI_HELP_REQUESTED)
4373 return CLI_HELP_NO_ARGS;
4374
4375 time(&time_now);
4376 for (i = 0; i < 64;++i) buckets[i] = 0;
4377
4378 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4379 {
4380 int idle;
4381 if (!session[s].opened)
4382 continue;
4383
4384 idle = time_now - session[s].last_packet;
4385 idle /= 5 ; // In multiples of 5 seconds.
4386 if (idle < 0)
4387 idle = 0;
4388 if (idle > 63)
4389 idle = 63;
4390
4391 ++count;
4392 ++buckets[idle];
4393 }
4394
4395 for (i = 0; i < 63; ++i)
4396 {
4397 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4398 }
4399 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4400 cli_print(cli, "%d total sessions open.", count);
4401 return CLI_OK;
4402 }
4403
4404 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4405 {
4406 int s, i;
4407 int count = 0;
4408 int buckets[64];
4409
4410 if (CLI_HELP_REQUESTED)
4411 return CLI_HELP_NO_ARGS;
4412
4413 time(&time_now);
4414 for (i = 0; i < 64;++i) buckets[i] = 0;
4415
4416 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4417 {
4418 int open = 0, d;
4419 if (!session[s].opened)
4420 continue;
4421
4422 d = time_now - session[s].opened;
4423 if (d < 0)
4424 d = 0;
4425 while (d > 1 && open < 32)
4426 {
4427 ++open;
4428 d >>= 1; // half.
4429 }
4430 ++count;
4431 ++buckets[open];
4432 }
4433
4434 s = 1;
4435 for (i = 0; i < 30; ++i)
4436 {
4437 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4438 s <<= 1;
4439 }
4440 cli_print(cli, "%d total sessions open.", count);
4441 return CLI_OK;
4442 }
4443
4444 /* Unhide an avp.
4445 *
4446 * This unencodes the AVP using the L2TP CHAP secret and the
4447 * previously stored random vector. It replaces the hidden data with
4448 * the cleartext data and returns the length of the cleartext data
4449 * (including the AVP "header" of 6 bytes).
4450 *
4451 * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
4452 */
4453 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
4454 {
4455 MD5_CTX ctx;
4456 uint8_t *cursor;
4457 uint8_t digest[16];
4458 uint8_t working_vector[16];
4459 uint16_t hidden_length;
4460 uint8_t type[2];
4461 size_t done, todo;
4462 uint8_t *output;
4463
4464 // Find the AVP type.
4465 type[0] = *(avp + 4);
4466 type[1] = *(avp + 5);
4467
4468 // Line up with the hidden data
4469 cursor = output = avp + 6;
4470
4471 // Compute initial pad
4472 MD5Init(&ctx);
4473 MD5Update(&ctx, type, 2);
4474 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4475 MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
4476 MD5Final(digest, &ctx);
4477
4478 // Get hidden length
4479 hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
4480
4481 // Keep these for later use
4482 working_vector[0] = *cursor;
4483 working_vector[1] = *(cursor + 1);
4484 cursor += 2;
4485
4486 if (hidden_length > length - 8)
4487 {
4488 LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
4489 return 0;
4490 }
4491
4492 /* Decrypt remainder */
4493 done = 2;
4494 todo = hidden_length;
4495 while (todo)
4496 {
4497 working_vector[done] = *cursor;
4498 *output = digest[done] ^ *cursor;
4499 ++output;
4500 ++cursor;
4501 --todo;
4502 ++done;
4503 if (done == 16 && todo)
4504 {
4505 // Compute new digest
4506 done = 0;
4507 MD5Init(&ctx);
4508 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4509 MD5Update(&ctx, &working_vector, 16);
4510 MD5Final(digest, &ctx);
4511 }
4512 }
4513
4514 return hidden_length + 6;
4515 }
4516
4517 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
4518 {
4519 switch (p->op)
4520 {
4521 case FILTER_PORT_OP_EQ: return port == p->port;
4522 case FILTER_PORT_OP_NEQ: return port != p->port;
4523 case FILTER_PORT_OP_GT: return port > p->port;
4524 case FILTER_PORT_OP_LT: return port < p->port;
4525 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
4526 }
4527
4528 return 0;
4529 }
4530
4531 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
4532 {
4533 switch (op)
4534 {
4535 case FILTER_FLAG_OP_ANY:
4536 return (flags & sflags) || (~flags & cflags);
4537
4538 case FILTER_FLAG_OP_ALL:
4539 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
4540
4541 case FILTER_FLAG_OP_EST:
4542 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
4543 }
4544
4545 return 0;
4546 }
4547
4548 int ip_filter(uint8_t *buf, int len, uint8_t filter)
4549 {
4550 uint16_t frag_offset;
4551 uint8_t proto;
4552 in_addr_t src_ip;
4553 in_addr_t dst_ip;
4554 uint16_t src_port = 0;
4555 uint16_t dst_port = 0;
4556 uint8_t flags = 0;
4557 ip_filter_rulet *rule;
4558
4559 if (len < 20) // up to end of destination address
4560 return 0;
4561
4562 if ((*buf >> 4) != 4) // IPv4
4563 return 0;
4564
4565 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
4566 proto = buf[9];
4567 src_ip = *(in_addr_t *) (buf + 12);
4568 dst_ip = *(in_addr_t *) (buf + 16);
4569
4570 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
4571 {
4572 int l = (buf[0] & 0xf) * 4; // length of IP header
4573 if (len < l + 4) // ports
4574 return 0;
4575
4576 src_port = ntohs(*(uint16_t *) (buf + l));
4577 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
4578 if (proto == IPPROTO_TCP)
4579 {
4580 if (len < l + 14) // flags
4581 return 0;
4582
4583 flags = buf[l + 13] & 0x3f;
4584 }
4585 }
4586
4587 for (rule = ip_filters[filter].rules; rule->action; rule++)
4588 {
4589 if (rule->proto != IPPROTO_IP && proto != rule->proto)
4590 continue;
4591
4592 if (rule->src_wild != INADDR_BROADCAST &&
4593 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
4594 continue;
4595
4596 if (rule->dst_wild != INADDR_BROADCAST &&
4597 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
4598 continue;
4599
4600 if (frag_offset)
4601 {
4602 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
4603 continue;
4604 }
4605 else
4606 {
4607 if (rule->frag)
4608 continue;
4609
4610 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
4611 {
4612 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
4613 continue;
4614
4615 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
4616 continue;
4617
4618 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
4619 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
4620 continue;
4621 }
4622 }
4623
4624 // matched
4625 rule->counter++;
4626 return rule->action == FILTER_ACTION_PERMIT;
4627 }
4628
4629 // default deny
4630 return 0;
4631 }