54b4667c098c8886f5b898e609fa768eded54849
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.57 2004/11/27 05:19:53 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 u32 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 u32 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 u32 udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
80 static u32 eth_rx = 0, eth_rx_pkt = 0;
81 u32 eth_tx = 0;
82
83 static u32 ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
84 time_t time_now = 0; // Current time in seconds since epoch.
85 static char time_now_string[64] = {0}; // Current time as a string.
86 static char main_quit = 0; // True if we're in the process of exiting.
87 linked_list *loaded_plugins;
88 linked_list *plugins[MAX_PLUGIN_TYPES];
89
90 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
91 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
92
93 config_descriptt config_values[] = {
94 CONFIG("debug", debug, INT),
95 CONFIG("log_file", log_filename, STRING),
96 CONFIG("pid_file", pid_file, STRING),
97 CONFIG("l2tp_secret", l2tpsecret, STRING),
98 CONFIG("primary_dns", default_dns1, IP),
99 CONFIG("secondary_dns", default_dns2, IP),
100 CONFIG("save_state", save_state, BOOL),
101 CONFIG("primary_radius", radiusserver[0], IP),
102 CONFIG("secondary_radius", radiusserver[1], IP),
103 CONFIG("primary_radius_port", radiusport[0], SHORT),
104 CONFIG("secondary_radius_port", radiusport[1], SHORT),
105 CONFIG("radius_accounting", radius_accounting, BOOL),
106 CONFIG("radius_secret", radiussecret, STRING),
107 CONFIG("bind_address", bind_address, IP),
108 CONFIG("peer_address", peer_address, IP),
109 CONFIG("send_garp", send_garp, BOOL),
110 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
111 CONFIG("throttle_buckets", num_tbfs, INT),
112 CONFIG("accounting_dir", accounting_dir, STRING),
113 CONFIG("setuid", target_uid, INT),
114 CONFIG("dump_speed", dump_speed, BOOL),
115 CONFIG("cleanup_interval", cleanup_interval, INT),
116 CONFIG("multi_read_count", multi_read_count, INT),
117 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
118 CONFIG("lock_pages", lock_pages, BOOL),
119 CONFIG("icmp_rate", icmp_rate, INT),
120 CONFIG("cluster_address", cluster_address, IP),
121 CONFIG("cluster_interface", cluster_interface, STRING),
122 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
123 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
124 { NULL, 0, 0, 0 },
125 };
126
127 static char *plugin_functions[] = {
128 NULL,
129 "plugin_pre_auth",
130 "plugin_post_auth",
131 "plugin_packet_rx",
132 "plugin_packet_tx",
133 "plugin_timer",
134 "plugin_new_session",
135 "plugin_kill_session",
136 "plugin_control",
137 "plugin_radius_response",
138 "plugin_become_master",
139 "plugin_new_session_master",
140 };
141
142 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
143
144 tunnelt *tunnel = NULL; // Array of tunnel structures.
145 sessiont *session = NULL; // Array of session structures.
146 sessioncountt *sess_count = NULL; // Array of partial per-session traffic counters.
147 radiust *radius = NULL; // Array of radius structures.
148 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
149 ip_filtert *ip_filters = NULL; // Array of named filters.
150 static controlt *controlfree = 0;
151 struct Tstats *_statistics = NULL;
152 #ifdef RINGBUFFER
153 struct Tringbuffer *ringbuffer = NULL;
154 #endif
155
156 static void cache_ipmap(ipt ip, int s);
157 static void uncache_ipmap(ipt ip);
158 static void free_ip_address(sessionidt s);
159 static void dump_acct_info(void);
160 static void sighup_handler(int sig);
161 static void sigalrm_handler(int sig);
162 static void sigterm_handler(int sig);
163 static void sigquit_handler(int sig);
164 static void sigchild_handler(int sig);
165 static void read_state(void);
166 static void dump_state(void);
167 static void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response);
168 static void update_config(void);
169 static void read_config_file(void);
170 static void initplugins(void);
171 static int add_plugin(char *plugin_name);
172 static int remove_plugin(char *plugin_name);
173 static void plugins_done(void);
174 static void processcontrol(u8 * buf, int len, struct sockaddr_in *addr, int alen);
175 static tunnelidt new_tunnel(void);
176 static int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length);
177
178 // return internal time (10ths since process startup)
179 static clockt now(void)
180 {
181 struct timeval t;
182 gettimeofday(&t, 0);
183 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
184 }
185
186 // work out a retry time based on try number
187 // This is a straight bounded exponential backoff.
188 // Maximum re-try time is 32 seconds. (2^5).
189 clockt backoff(u8 try)
190 {
191 if (try > 5) try = 5; // max backoff
192 return now() + 10 * (1 << try);
193 }
194
195
196 //
197 // Log a debug message. Typically called vias LOG macro
198 //
199 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...)
200 {
201 static char message[65536] = {0};
202 static char message2[65536] = {0};
203 va_list ap;
204
205 #ifdef RINGBUFFER
206 if (ringbuffer)
207 {
208 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
209 ringbuffer->tail = 0;
210 if (ringbuffer->tail == ringbuffer->head)
211 if (++ringbuffer->head >= RINGBUFFER_SIZE)
212 ringbuffer->head = 0;
213
214 ringbuffer->buffer[ringbuffer->tail].level = level;
215 ringbuffer->buffer[ringbuffer->tail].address = address;
216 ringbuffer->buffer[ringbuffer->tail].session = s;
217 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
218 va_start(ap, format);
219 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
220 va_end(ap);
221 }
222 #endif
223
224 if (config->debug < level) return;
225
226 va_start(ap, format);
227 if (log_stream)
228 {
229 vsnprintf(message2, 65535, format, ap);
230 snprintf(message, 65535, "%s %02d/%02d %s", time_now_string, t, s, message2);
231 fprintf(log_stream, "%s", message);
232 }
233 else if (syslog_log)
234 {
235 vsnprintf(message2, 65535, format, ap);
236 snprintf(message, 65535, "%02d/%02d %s", t, s, message2);
237 syslog(level + 2, message); // We don't need LOG_EMERG or LOG_ALERT
238 }
239 va_end(ap);
240 }
241
242 void _log_hex(int level, const char *title, const char *data, int maxsize)
243 {
244 int i, j;
245 const u8 *d = (const u8 *)data;
246
247 if (config->debug < level) return;
248
249 // No support for _log_hex to syslog
250 if (log_stream)
251 {
252 _log(level, 0, 0, 0, "%s (%d bytes):\n", title, maxsize);
253 setvbuf(log_stream, NULL, _IOFBF, 16384);
254
255 for (i = 0; i < maxsize; )
256 {
257 fprintf(log_stream, "%4X: ", i);
258 for (j = i; j < maxsize && j < (i + 16); j++)
259 {
260 fprintf(log_stream, "%02X ", d[j]);
261 if (j == i + 7)
262 fputs(": ", log_stream);
263 }
264
265 for (; j < i + 16; j++)
266 {
267 fputs(" ", log_stream);
268 if (j == i + 7)
269 fputs(": ", log_stream);
270 }
271
272 fputs(" ", log_stream);
273 for (j = i; j < maxsize && j < (i + 16); j++)
274 {
275 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
276 fputc(d[j], log_stream);
277 else
278 fputc('.', log_stream);
279
280 if (j == i + 7)
281 fputs(" ", log_stream);
282 }
283
284 i = j;
285 fputs("\n", log_stream);
286 }
287
288 fflush(log_stream);
289 setbuf(log_stream, NULL);
290 }
291 }
292
293
294 // Add a route
295 //
296 // This adds it to the routing table, advertises it
297 // via BGP if enabled, and stuffs it into the
298 // 'sessionbyip' cache.
299 //
300 // 'ip' and 'mask' must be in _host_ order.
301 //
302 static void routeset(sessionidt s, ipt ip, ipt mask, ipt gw, u8 add)
303 {
304 struct rtentry r;
305 int i;
306
307 if (!mask) mask = 0xffffffff;
308
309 ip &= mask; // Force the ip to be the first one in the route.
310
311 memset(&r, 0, sizeof(r));
312 r.rt_dev = config->tundevice;
313 r.rt_dst.sa_family = AF_INET;
314 *(u32 *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
315 r.rt_gateway.sa_family = AF_INET;
316 *(u32 *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
317 r.rt_genmask.sa_family = AF_INET;
318 *(u32 *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
319 r.rt_flags = (RTF_UP | RTF_STATIC);
320 if (gw)
321 r.rt_flags |= RTF_GATEWAY;
322 else if (mask == 0xffffffff)
323 r.rt_flags |= RTF_HOST;
324
325 LOG(1, ip, 0, 0, "Route %s %u.%u.%u.%u/%u.%u.%u.%u %u.%u.%u.%u\n",
326 add ? "add" : "del",
327 ip >> 24, ip >> 16 & 0xff, ip >> 8 & 0xff, ip & 0xff,
328 mask >> 24, mask >> 16 & 0xff, mask >> 8 & 0xff, mask & 0xff,
329 gw >> 24, gw >> 16 & 0xff, gw >> 8 & 0xff, gw & 0xff);
330
331 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
332 LOG(0, 0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
333
334 #ifdef BGP
335 if (add)
336 bgp_add_route(htonl(ip), htonl(mask));
337 else
338 bgp_del_route(htonl(ip), htonl(mask));
339 #endif /* BGP */
340
341 // Add/Remove the IPs to the 'sessionbyip' cache.
342 // Note that we add the zero address in the case of
343 // a network route. Roll on CIDR.
344
345 // Note that 's == 0' implies this is the address pool.
346 // We still cache it here, because it will pre-fill
347 // the malloc'ed tree.
348
349 if (s)
350 {
351 if (!add) // Are we deleting a route?
352 s = 0; // Caching the session as '0' is the same as uncaching.
353
354 for (i = ip; (i&mask) == (ip&mask) ; ++i)
355 cache_ipmap(i, s);
356 }
357 }
358
359 //
360 // Set up TUN interface
361 static void inittun(void)
362 {
363 struct ifreq ifr;
364 struct sockaddr_in sin = {0};
365 memset(&ifr, 0, sizeof(ifr));
366 ifr.ifr_flags = IFF_TUN;
367
368 tunfd = open(TUNDEVICE, O_RDWR);
369 if (tunfd < 0)
370 { // fatal
371 LOG(0, 0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
372 exit(1);
373 }
374 {
375 int flags = fcntl(tunfd, F_GETFL, 0);
376 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
377 }
378 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
379 {
380 LOG(0, 0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
381 exit(1);
382 }
383 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
384 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
385 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
386
387 sin.sin_family = AF_INET;
388 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
389 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
390
391 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
392 {
393 LOG(0, 0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
394 exit(1);
395 }
396 /* Bump up the qlen to deal with bursts from the network */
397 ifr.ifr_qlen = 1000;
398 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
399 {
400 LOG(0, 0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
401 exit(1);
402 }
403 ifr.ifr_flags = IFF_UP;
404 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
405 {
406 LOG(0, 0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
407 exit(1);
408 }
409 }
410
411 // set up UDP port
412 static void initudp(void)
413 {
414 int on = 1;
415 struct sockaddr_in addr;
416
417 // Tunnel
418 memset(&addr, 0, sizeof(addr));
419 addr.sin_family = AF_INET;
420 addr.sin_port = htons(L2TPPORT);
421 addr.sin_addr.s_addr = config->bind_address;
422 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
423 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
424 {
425 int flags = fcntl(udpfd, F_GETFL, 0);
426 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
427 }
428 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
429 {
430 LOG(0, 0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
431 exit(1);
432 }
433 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
434
435 // Control
436 memset(&addr, 0, sizeof(addr));
437 addr.sin_family = AF_INET;
438 addr.sin_port = htons(NSCTL_PORT);
439 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
440 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
441 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
442 {
443 LOG(0, 0, 0, 0, "Error in control bind: %s\n", strerror(errno));
444 exit(1);
445 }
446 }
447
448 //
449 // Find session by IP, < 1 for not found
450 //
451 // Confusingly enough, this 'ip' must be
452 // in _network_ order. This being the common
453 // case when looking it up from IP packet headers.
454 //
455 // We actually use this cache for two things.
456 // #1. For used IP addresses, this maps to the
457 // session ID that it's used by.
458 // #2. For un-used IP addresses, this maps to the
459 // index into the pool table that contains that
460 // IP address.
461 //
462
463 static int lookup_ipmap(ipt ip)
464 {
465 u8 *a = (u8 *)&ip;
466 char **d = (char **) ip_hash;
467 int s;
468
469 if (!(d = (char **) d[(size_t) *a++])) return 0;
470 if (!(d = (char **) d[(size_t) *a++])) return 0;
471 if (!(d = (char **) d[(size_t) *a++])) return 0;
472
473 s = (ipt) d[(size_t) *a];
474 return s;
475 }
476
477 sessionidt sessionbyip(ipt ip)
478 {
479 int s = lookup_ipmap(ip);
480 CSTAT(call_sessionbyip);
481
482 if (s > 0 && s < MAXSESSION && session[s].tunnel)
483 return s;
484 return 0;
485 }
486
487 //
488 // Take an IP address in HOST byte order and
489 // add it to the sessionid by IP cache.
490 //
491 // (It's actually cached in network order)
492 //
493 static void cache_ipmap(ipt ip, int s)
494 {
495 ipt nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char*)(&ip))[0]
496 u8 *a = (u8 *) &nip;
497 char **d = (char **) ip_hash;
498 int i;
499
500 for (i = 0; i < 3; i++)
501 {
502 if (!d[(size_t) a[i]])
503 {
504 if (!(d[(size_t) a[i]] = calloc(256, sizeof (void *))))
505 return;
506 }
507
508 d = (char **) d[(size_t) a[i]];
509 }
510
511 d[(size_t) a[3]] = (char *)((int)s);
512
513 if (s > 0)
514 LOG(4, ip, s, session[s].tunnel, "Caching ip address %s\n", inet_toa(nip));
515 else if (s == 0)
516 LOG(4, ip, 0, 0, "Un-caching ip address %s\n", inet_toa(nip));
517 // else a map to an ip pool index.
518 }
519
520 static void uncache_ipmap(ipt ip)
521 {
522 cache_ipmap(ip, 0); // Assign it to the NULL session.
523 }
524
525 //
526 // CLI list to dump current ipcache.
527 //
528 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
529 {
530 char **d = (char **) ip_hash, **e, **f, **g;
531 int i, j, k, l;
532 int count = 0;
533
534 if (CLI_HELP_REQUESTED)
535 return CLI_HELP_NO_ARGS;
536
537 cli_print(cli, "%7s %s", "Sess#", "IP Address");
538
539 for (i = 0; i < 256; ++i)
540 {
541 if (!d[i])
542 continue;
543 e = (char**) d[i];
544 for (j = 0; j < 256; ++j)
545 {
546 if (!e[j])
547 continue;
548 f = (char**) e[j];
549 for (k = 0; k < 256; ++k)
550 {
551 if (!f[k])
552 continue;
553 g = (char**)f[k];
554 for (l = 0; l < 256; ++l)
555 {
556 if (!g[l])
557 continue;
558 cli_print(cli, "%7d %d.%d.%d.%d", (int) g[l], i, j, k, l);
559 ++count;
560 }
561 }
562 }
563 }
564 cli_print(cli, "%d entries in cache", count);
565 return CLI_OK;
566 }
567
568
569 // Find session by username, 0 for not found
570 // walled garden users aren't authenticated, so the username is
571 // reasonably useless. Ignore them to avoid incorrect actions
572 //
573 // This is VERY inefficent. Don't call it often. :)
574 //
575 sessionidt sessionbyuser(char *username)
576 {
577 int s;
578 CSTAT(call_sessionbyuser);
579
580 for (s = 1; s < MAXSESSION ; ++s)
581 {
582 if (session[s].walled_garden)
583 continue; // Skip walled garden users.
584
585 if (!strncmp(session[s].user, username, 128))
586 return s;
587
588 }
589 return 0; // Not found.
590 }
591
592 void send_garp(ipt ip)
593 {
594 int s;
595 struct ifreq ifr;
596 u8 mac[6];
597
598 s = socket(PF_INET, SOCK_DGRAM, 0);
599 if (s < 0)
600 {
601 LOG(0, 0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
602 return;
603 }
604 memset(&ifr, 0, sizeof(ifr));
605 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
606 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
607 {
608 LOG(0, 0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
609 close(s);
610 return;
611 }
612 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
613 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
614 {
615 LOG(0, 0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
616 close(s);
617 return;
618 }
619 close(s);
620 sendarp(ifr.ifr_ifindex, mac, ip);
621 }
622
623 // Find session by username, 0 for not found
624 static sessiont *sessiontbysessionidt(sessionidt s)
625 {
626 if (!s || s > MAXSESSION) return NULL;
627 return &session[s];
628 }
629
630 static sessionidt sessionidtbysessiont(sessiont *s)
631 {
632 sessionidt val = s-session;
633 if (s < session || val > MAXSESSION) return 0;
634 return val;
635 }
636
637 // actually send a control message for a specific tunnel
638 void tunnelsend(u8 * buf, u16 l, tunnelidt t)
639 {
640 struct sockaddr_in addr;
641
642 CSTAT(call_tunnelsend);
643
644 if (!t)
645 {
646 static int backtrace_count = 0;
647 LOG(0, 0, 0, t, "tunnelsend called with 0 as tunnel id\n");
648 STAT(tunnel_tx_errors);
649 log_backtrace(backtrace_count, 5)
650 return;
651 }
652
653 if (!tunnel[t].ip)
654 {
655 static int backtrace_count = 0;
656 LOG(1, 0, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
657 log_backtrace(backtrace_count, 5)
658 STAT(tunnel_tx_errors);
659 return;
660 }
661
662 memset(&addr, 0, sizeof(addr));
663 addr.sin_family = AF_INET;
664 *(u32 *) & addr.sin_addr = htonl(tunnel[t].ip);
665 addr.sin_port = htons(tunnel[t].port);
666
667 // sequence expected, if sequence in message
668 if (*buf & 0x08) *(u16 *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
669
670 // If this is a control message, deal with retries
671 if (*buf & 0x80)
672 {
673 tunnel[t].last = time_now; // control message sent
674 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
675 if (tunnel[t].try > 1)
676 {
677 STAT(tunnel_retries);
678 LOG(3, tunnel[t].ip, 0, t, "Control message resend try %d\n", tunnel[t].try);
679 }
680 }
681
682 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
683 {
684 LOG(0, tunnel[t].ip, ntohs((*(u16 *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
685 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
686 STAT(tunnel_tx_errors);
687 return;
688 }
689
690 LOG_HEX(5, "Send Tunnel Data", buf, l);
691 STAT(tunnel_tx_packets);
692 INC_STAT(tunnel_tx_bytes, l);
693 }
694
695 //
696 // Tiny helper function to write data to
697 // the 'tun' device.
698 //
699 int tun_write(u8 * data, int size)
700 {
701 return write(tunfd, data, size);
702 }
703
704 // process outgoing (to tunnel) IP
705 //
706 static void processipout(u8 * buf, int len)
707 {
708 sessionidt s;
709 sessiont *sp;
710 tunnelidt t;
711 ipt ip;
712
713 char * data = buf; // Keep a copy of the originals.
714 int size = len;
715
716 u8 b[MAXETHER + 20];
717
718 CSTAT(call_processipout);
719
720 if (len < MIN_IP_SIZE)
721 {
722 LOG(1, 0, 0, 0, "Short IP, %d bytes\n", len);
723 STAT(tunnel_tx_errors);
724 return;
725 }
726 if (len >= MAXETHER)
727 {
728 LOG(1, 0, 0, 0, "Oversize IP packet %d bytes\n", len);
729 STAT(tunnel_tx_errors);
730 return;
731 }
732
733 // Skip the tun header
734 buf += 4;
735 len -= 4;
736
737 // Got an IP header now
738 if (*(u8 *)(buf) >> 4 != 4)
739 {
740 LOG(1, 0, 0, 0, "IP: Don't understand anything except IPv4\n");
741 return;
742 }
743
744 ip = *(u32 *)(buf + 16);
745 if (!(s = sessionbyip(ip)))
746 {
747 // Is this a packet for a session that doesn't exist?
748 static int rate = 0; // Number of ICMP packets we've sent this second.
749 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
750
751 if (last != time_now)
752 {
753 last = time_now;
754 rate = 0;
755 }
756
757 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
758 {
759 LOG(4, 0, 0, 0, "IP: Sending ICMP host unreachable to %s\n", inet_toa(*(u32 *)(buf + 12)));
760 host_unreachable(*(u32 *)(buf + 12), *(u16 *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
761 }
762 return;
763 }
764 t = session[s].tunnel;
765 sp = &session[s];
766
767 if (sp->tbf_out)
768 {
769 // Are we throttling this session?
770 if (config->cluster_iam_master)
771 tbf_queue_packet(sp->tbf_out, data, size);
772 else
773 master_throttle_packet(sp->tbf_out, data, size);
774 return;
775 }
776 else if (sp->walled_garden && !config->cluster_iam_master)
777 {
778 // We are walled-gardening this
779 master_garden_packet(s, data, size);
780 return;
781 }
782
783 LOG(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
784
785 // Add on L2TP header
786 {
787 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
788 if (!p) return;
789 tunnelsend(b, len + (p-b), t); // send it...
790 }
791
792 // Snooping this session, send it to intercept box
793 if (sp->snoop_ip && sp->snoop_port)
794 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
795
796 sp->cout += len; // byte count
797 sp->total_cout += len; // byte count
798 sp->pout++;
799 udp_tx += len;
800 sess_count[s].cout += len; // To send to master..
801 }
802
803 //
804 // Helper routine for the TBF filters.
805 // Used to send queued data in to the user!
806 //
807 static void send_ipout(sessionidt s, u8 *buf, int len)
808 {
809 sessiont *sp;
810 tunnelidt t;
811 ipt ip;
812
813 u8 b[MAXETHER + 20];
814
815 if (len < 0 || len > MAXETHER)
816 {
817 LOG(1,0,0,0, "Odd size IP packet: %d bytes\n", len);
818 return;
819 }
820
821 // Skip the tun header
822 buf += 4;
823 len -= 4;
824
825 ip = *(u32 *)(buf + 16);
826
827 if (!session[s].ip)
828 return;
829
830 t = session[s].tunnel;
831 sp = &session[s];
832
833 LOG(5, session[s].ip, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
834
835 // Add on L2TP header
836 {
837 u8 *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
838 if (!p) return;
839 tunnelsend(b, len + (p-b), t); // send it...
840 }
841
842 // Snooping this session.
843 if (sp->snoop_ip && sp->snoop_port)
844 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
845
846 sp->cout += len; // byte count
847 sp->total_cout += len; // byte count
848 sp->pout++;
849 udp_tx += len;
850 sess_count[s].cout += len; // To send to master..
851 }
852
853 // add an AVP (16 bit)
854 static void control16(controlt * c, u16 avp, u16 val, u8 m)
855 {
856 u16 l = (m ? 0x8008 : 0x0008);
857 *(u16 *) (c->buf + c->length + 0) = htons(l);
858 *(u16 *) (c->buf + c->length + 2) = htons(0);
859 *(u16 *) (c->buf + c->length + 4) = htons(avp);
860 *(u16 *) (c->buf + c->length + 6) = htons(val);
861 c->length += 8;
862 }
863
864 // add an AVP (32 bit)
865 static void control32(controlt * c, u16 avp, u32 val, u8 m)
866 {
867 u16 l = (m ? 0x800A : 0x000A);
868 *(u16 *) (c->buf + c->length + 0) = htons(l);
869 *(u16 *) (c->buf + c->length + 2) = htons(0);
870 *(u16 *) (c->buf + c->length + 4) = htons(avp);
871 *(u32 *) (c->buf + c->length + 6) = htonl(val);
872 c->length += 10;
873 }
874
875 // add an AVP (32 bit)
876 static void controls(controlt * c, u16 avp, char *val, u8 m)
877 {
878 u16 l = ((m ? 0x8000 : 0) + strlen(val) + 6);
879 *(u16 *) (c->buf + c->length + 0) = htons(l);
880 *(u16 *) (c->buf + c->length + 2) = htons(0);
881 *(u16 *) (c->buf + c->length + 4) = htons(avp);
882 memcpy(c->buf + c->length + 6, val, strlen(val));
883 c->length += 6 + strlen(val);
884 }
885
886 // add a binary AVP
887 static void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m)
888 {
889 u16 l = ((m ? 0x8000 : 0) + len + 6);
890 *(u16 *) (c->buf + c->length + 0) = htons(l);
891 *(u16 *) (c->buf + c->length + 2) = htons(0);
892 *(u16 *) (c->buf + c->length + 4) = htons(avp);
893 memcpy(c->buf + c->length + 6, val, len);
894 c->length += 6 + len;
895 }
896
897 // new control connection
898 static controlt *controlnew(u16 mtype)
899 {
900 controlt *c;
901 if (!controlfree)
902 c = malloc(sizeof(controlt));
903 else
904 {
905 c = controlfree;
906 controlfree = c->next;
907 }
908 assert(c);
909 c->next = 0;
910 *(u16 *) (c->buf + 0) = htons(0xC802); // flags/ver
911 c->length = 12;
912 control16(c, 0, mtype, 1);
913 return c;
914 }
915
916 // send zero block if nothing is waiting
917 // (ZLB send).
918 static void controlnull(tunnelidt t)
919 {
920 u8 buf[12];
921 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
922 return;
923
924 *(u16 *) (buf + 0) = htons(0xC802); // flags/ver
925 *(u16 *) (buf + 2) = htons(12); // length
926 *(u16 *) (buf + 4) = htons(tunnel[t].far); // tunnel
927 *(u16 *) (buf + 6) = htons(0); // session
928 *(u16 *) (buf + 8) = htons(tunnel[t].ns); // sequence
929 *(u16 *) (buf + 10) = htons(tunnel[t].nr); // sequence
930 tunnelsend(buf, 12, t);
931 }
932
933 // add a control message to a tunnel, and send if within window
934 static void controladd(controlt * c, tunnelidt t, sessionidt s)
935 {
936 *(u16 *) (c->buf + 2) = htons(c->length); // length
937 *(u16 *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
938 *(u16 *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
939 *(u16 *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
940 tunnel[t].ns++; // advance sequence
941 // link in message in to queue
942 if (tunnel[t].controlc)
943 tunnel[t].controle->next = c;
944 else
945 tunnel[t].controls = c;
946
947 tunnel[t].controle = c;
948 tunnel[t].controlc++;
949
950 // send now if space in window
951 if (tunnel[t].controlc <= tunnel[t].window)
952 {
953 tunnel[t].try = 0; // first send
954 tunnelsend(c->buf, c->length, t);
955 }
956 }
957
958 //
959 // Throttle or Unthrottle a session
960 //
961 // Throttle the data from/to through a session to no more than
962 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
963 // user).
964 //
965 // If either value is -1, the current value is retained for that
966 // direction.
967 //
968 void throttle_session(sessionidt s, int rate_in, int rate_out)
969 {
970 if (!session[s].tunnel)
971 return; // No-one home.
972
973 if (!*session[s].user)
974 return; // User not logged in
975
976 if (rate_in >= 0)
977 {
978 int bytes = rate_in * 1024 / 8; // kbits to bytes
979 if (session[s].tbf_in)
980 free_tbf(session[s].tbf_in);
981
982 if (rate_in > 0)
983 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
984 else
985 session[s].tbf_in = 0;
986
987 session[s].throttle_in = rate_in;
988 }
989
990 if (rate_out >= 0)
991 {
992 int bytes = rate_out * 1024 / 8;
993 if (session[s].tbf_out)
994 free_tbf(session[s].tbf_out);
995
996 if (rate_out > 0)
997 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
998 else
999 session[s].tbf_out = 0;
1000
1001 session[s].throttle_out = rate_out;
1002 }
1003 }
1004
1005 // start tidy shutdown of session
1006 void sessionshutdown(sessionidt s, char *reason)
1007 {
1008 int walled_garden = session[s].walled_garden;
1009
1010
1011 CSTAT(call_sessionshutdown);
1012
1013 if (!session[s].tunnel)
1014 {
1015 LOG(3, session[s].ip, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1016 return; // not a live session
1017 }
1018
1019 if (!session[s].die)
1020 {
1021 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1022 LOG(2, 0, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1023 run_plugins(PLUGIN_KILL_SESSION, &data);
1024 }
1025
1026 // RADIUS Stop message
1027 if (session[s].opened && !walled_garden && !session[s].die)
1028 {
1029 u16 r = session[s].radius;
1030 if (!r)
1031 {
1032 if (!(r = radiusnew(s)))
1033 {
1034 LOG(1, 0, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1035 STAT(radius_overflow);
1036 }
1037 else
1038 {
1039 int n;
1040 for (n = 0; n < 15; n++)
1041 radius[r].auth[n] = rand();
1042 }
1043 }
1044 if (r && radius[r].state != RADIUSSTOP)
1045 radiussend(r, RADIUSSTOP); // stop, if not already trying
1046 }
1047
1048 if (session[s].ip)
1049 { // IP allocated, clear and unroute
1050 int r;
1051 int routed = 0;
1052 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1053 {
1054 if ((session[s].ip & session[s].route[r].mask) ==
1055 (session[s].route[r].ip & session[s].route[r].mask))
1056 routed++;
1057
1058 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1059 session[s].route[r].ip = 0;
1060 }
1061
1062 if (session[s].ip_pool_index == -1) // static ip
1063 {
1064 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1065 session[s].ip = 0;
1066 }
1067 else
1068 free_ip_address(s);
1069 }
1070
1071 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1072 throttle_session(s, 0, 0);
1073
1074 { // Send CDN
1075 controlt *c = controlnew(14); // sending CDN
1076 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1077 control16(c, 14, s, 1); // assigned session (our end)
1078 controladd(c, session[s].tunnel, s); // send the message
1079 }
1080
1081 if (!session[s].die)
1082 session[s].die = now() + 150; // Clean up in 15 seconds
1083
1084 cluster_send_session(s);
1085 }
1086
1087 void sendipcp(tunnelidt t, sessionidt s)
1088 {
1089 u8 buf[MAXCONTROL];
1090 u16 r = session[s].radius;
1091 u8 *q;
1092
1093 CSTAT(call_sendipcp);
1094
1095 if (!r)
1096 r = radiusnew(s);
1097
1098 if (radius[r].state != RADIUSIPCP)
1099 {
1100 radius[r].state = RADIUSIPCP;
1101 radius[r].try = 0;
1102 }
1103
1104 radius[r].retry = backoff(radius[r].try++);
1105 if (radius[r].try > 10)
1106 {
1107 radiusclear(r, s); // Clear radius session.
1108 sessionshutdown(s, "No reply on IPCP");
1109 return;
1110 }
1111
1112 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1113 if (!q) return;
1114
1115 *q = ConfigReq;
1116 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1117 *(u16 *) (q + 2) = htons(10);
1118 q[4] = 3;
1119 q[5] = 6;
1120 *(u32 *) (q + 6) = config->peer_address ? config->peer_address :
1121 config->bind_address ? config->bind_address :
1122 my_address; // send my IP
1123
1124 tunnelsend(buf, 10 + (q - buf), t); // send it
1125 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1126 }
1127
1128 // kill a session now
1129 static void sessionkill(sessionidt s, char *reason)
1130 {
1131
1132 CSTAT(call_sessionkill);
1133
1134 session[s].die = now();
1135 sessionshutdown(s, reason); // close radius/routes, etc.
1136 if (session[s].radius)
1137 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1138
1139 LOG(2, 0, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1140
1141 memset(&session[s], 0, sizeof(session[s]));
1142 session[s].tunnel = T_FREE; // Mark it as free.
1143 session[s].next = sessionfree;
1144 sessionfree = s;
1145 cli_session_actions[s].action = 0;
1146 cluster_send_session(s);
1147 }
1148
1149 static void tunnelclear(tunnelidt t)
1150 {
1151 if (!t) return;
1152 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1153 tunnel[t].state = TUNNELFREE;
1154 }
1155
1156 // kill a tunnel now
1157 static void tunnelkill(tunnelidt t, char *reason)
1158 {
1159 sessionidt s;
1160 controlt *c;
1161
1162 CSTAT(call_tunnelkill);
1163
1164 tunnel[t].state = TUNNELDIE;
1165
1166 // free control messages
1167 while ((c = tunnel[t].controls))
1168 {
1169 controlt * n = c->next;
1170 tunnel[t].controls = n;
1171 tunnel[t].controlc--;
1172 c->next = controlfree;
1173 controlfree = c;
1174 }
1175 // kill sessions
1176 for (s = 1; s < MAXSESSION; s++)
1177 if (session[s].tunnel == t)
1178 sessionkill(s, reason);
1179
1180 // free tunnel
1181 tunnelclear(t);
1182 LOG(1, 0, 0, t, "Kill tunnel %d: %s\n", t, reason);
1183 cli_tunnel_actions[s].action = 0;
1184 cluster_send_tunnel(t);
1185 }
1186
1187 // shut down a tunnel cleanly
1188 static void tunnelshutdown(tunnelidt t, char *reason)
1189 {
1190 sessionidt s;
1191
1192 CSTAT(call_tunnelshutdown);
1193
1194 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1195 {
1196 // never set up, can immediately kill
1197 tunnelkill(t, reason);
1198 return;
1199 }
1200 LOG(1, 0, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1201
1202 // close session
1203 for (s = 1; s < MAXSESSION; s++)
1204 if (session[s].tunnel == t)
1205 sessionshutdown(s, reason);
1206
1207 tunnel[t].state = TUNNELDIE;
1208 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1209 cluster_send_tunnel(t);
1210 // TBA - should we wait for sessions to stop?
1211 { // Send StopCCN
1212 controlt *c = controlnew(4); // sending StopCCN
1213 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message
1214 control16(c, 9, t, 1); // assigned tunnel (our end)
1215 controladd(c, t, 0); // send the message
1216 }
1217 }
1218
1219 // read and process packet on tunnel (UDP)
1220 void processudp(u8 * buf, int len, struct sockaddr_in *addr)
1221 {
1222 char *chapresponse = NULL;
1223 u16 l = len, t = 0, s = 0, ns = 0, nr = 0;
1224 u8 *p = buf + 2;
1225
1226
1227 CSTAT(call_processudp);
1228
1229 udp_rx += len;
1230 udp_rx_pkt++;
1231 LOG_HEX(5, "UDP Data", buf, len);
1232 STAT(tunnel_rx_packets);
1233 INC_STAT(tunnel_rx_bytes, len);
1234 if (len < 6)
1235 {
1236 LOG(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Short UDP, %d bytes\n", len);
1237 STAT(tunnel_rx_errors);
1238 return;
1239 }
1240 if ((buf[1] & 0x0F) != 2)
1241 {
1242 LOG(1, ntohl(addr->sin_addr.s_addr), 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1243 STAT(tunnel_rx_errors);
1244 return;
1245 }
1246 if (*buf & 0x40)
1247 { // length
1248 l = ntohs(*(u16 *) p);
1249 p += 2;
1250 }
1251 t = ntohs(*(u16 *) p);
1252 p += 2;
1253 s = ntohs(*(u16 *) p);
1254 p += 2;
1255 if (s >= MAXSESSION)
1256 {
1257 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid session ID\n");
1258 STAT(tunnel_rx_errors);
1259 return;
1260 }
1261 if (t >= MAXTUNNEL)
1262 {
1263 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Received UDP packet with invalid tunnel ID\n");
1264 STAT(tunnel_rx_errors);
1265 return;
1266 }
1267 if (*buf & 0x08)
1268 { // ns/nr
1269 ns = ntohs(*(u16 *) p);
1270 p += 2;
1271 nr = ntohs(*(u16 *) p);
1272 p += 2;
1273 }
1274 if (*buf & 0x02)
1275 { // offset
1276 u16 o = ntohs(*(u16 *) p);
1277 p += o + 2;
1278 }
1279 if ((p - buf) > l)
1280 {
1281 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad length %d>%d\n", (p - buf), l);
1282 STAT(tunnel_rx_errors);
1283 return;
1284 }
1285 l -= (p - buf);
1286 if (*buf & 0x80)
1287 { // control
1288 u16 message = 0xFFFF; // message type
1289 u8 fatal = 0;
1290 u8 mandatorymessage = 0;
1291 u8 chap = 0; // if CHAP being used
1292 u16 asession = 0; // assigned session
1293 u32 amagic = 0; // magic number
1294 u8 aflags = 0; // flags from last LCF
1295 u16 version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1296 int requestchap = 0; // do we request PAP instead of original CHAP request?
1297 char called[MAXTEL] = ""; // called number
1298 char calling[MAXTEL] = ""; // calling number
1299
1300 if (!config->cluster_iam_master)
1301 {
1302 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1303 return;
1304 }
1305
1306 if ((*buf & 0xCA) != 0xC8)
1307 {
1308 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Bad control header %02X\n", *buf);
1309 STAT(tunnel_rx_errors);
1310 return;
1311 }
1312
1313 // check for duplicate tunnel open message
1314 if (!t && ns == 0)
1315 {
1316 int i;
1317
1318 //
1319 // Is this a duplicate of the first packet? (SCCRQ)
1320 //
1321 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1322 {
1323 if (tunnel[i].state != TUNNELOPENING ||
1324 tunnel[i].ip != ntohl(*(ipt *) & addr->sin_addr) ||
1325 tunnel[i].port != ntohs(addr->sin_port) )
1326 continue;
1327 t = i;
1328 LOG(3, ntohl(addr->sin_addr.s_addr), s, t, "Duplicate SCCRQ?\n");
1329 break;
1330 }
1331 }
1332
1333 LOG(3, ntohl(addr->sin_addr.s_addr), s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1334 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1335
1336 // if no tunnel specified, assign one
1337 if (!t)
1338 {
1339 if (!(t = new_tunnel()))
1340 {
1341 LOG(1, ntohl(addr->sin_addr.s_addr), 0, 0, "No more tunnels\n");
1342 STAT(tunnel_overflow);
1343 return;
1344 }
1345 tunnelclear(t);
1346 tunnel[t].ip = ntohl(*(ipt *) & addr->sin_addr);
1347 tunnel[t].port = ntohs(addr->sin_port);
1348 tunnel[t].window = 4; // default window
1349 STAT(tunnel_created);
1350 LOG(1, ntohl(addr->sin_addr.s_addr), 0, t, " New tunnel from %u.%u.%u.%u/%u ID %d\n",
1351 tunnel[t].ip >> 24, tunnel[t].ip >> 16 & 255,
1352 tunnel[t].ip >> 8 & 255, tunnel[t].ip & 255, tunnel[t].port, t);
1353 }
1354
1355 // If the 'ns' just received is not the 'nr' we're
1356 // expecting, just send an ack and drop it.
1357 //
1358 // if 'ns' is less, then we got a retransmitted packet.
1359 // if 'ns' is greater than missed a packet. Either way
1360 // we should ignore it.
1361 if (ns != tunnel[t].nr)
1362 {
1363 // is this the sequence we were expecting?
1364 STAT(tunnel_rx_errors);
1365 LOG(1, ntohl(addr->sin_addr.s_addr), 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1366 t, ns, tunnel[t].nr);
1367
1368 if (l) // Is this not a ZLB?
1369 controlnull(t);
1370 return;
1371 }
1372
1373 // This is used to time out old tunnels
1374 tunnel[t].lastrec = time_now;
1375
1376 // check sequence of this message
1377 {
1378 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1379 // some to clear maybe?
1380 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1381 {
1382 controlt *c = tunnel[t].controls;
1383 tunnel[t].controls = c->next;
1384 tunnel[t].controlc--;
1385 c->next = controlfree;
1386 controlfree = c;
1387 skip--;
1388 tunnel[t].try = 0; // we have progress
1389 }
1390
1391 // receiver advance (do here so quoted correctly in any sends below)
1392 if (l) tunnel[t].nr = (ns + 1);
1393 if (skip < 0) skip = 0;
1394 if (skip < tunnel[t].controlc)
1395 {
1396 // some control packets can now be sent that were previous stuck out of window
1397 int tosend = tunnel[t].window - skip;
1398 controlt *c = tunnel[t].controls;
1399 while (c && skip)
1400 {
1401 c = c->next;
1402 skip--;
1403 }
1404 while (c && tosend)
1405 {
1406 tunnel[t].try = 0; // first send
1407 tunnelsend(c->buf, c->length, t);
1408 c = c->next;
1409 tosend--;
1410 }
1411 }
1412 if (!tunnel[t].controlc)
1413 tunnel[t].retry = 0; // caught up
1414 }
1415 if (l)
1416 { // if not a null message
1417 // process AVPs
1418 while (l && !(fatal & 0x80))
1419 {
1420 u16 n = (ntohs(*(u16 *) p) & 0x3FF);
1421 u8 *b = p;
1422 u8 flags = *p;
1423 u16 mtype;
1424 p += n; // next
1425 if (l < n)
1426 {
1427 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Invalid length in AVP\n");
1428 STAT(tunnel_rx_errors);
1429 fatal = flags;
1430 return;
1431 }
1432 l -= n;
1433 if (flags & 0x40)
1434 {
1435 // handle hidden AVPs
1436 if (!*config->l2tpsecret)
1437 {
1438 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no L2TP secret.\n");
1439 fatal = flags;
1440 continue;
1441 }
1442 if (!session[s].random_vector_length)
1443 {
1444 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP requested, but no random vector.\n");
1445 fatal = flags;
1446 continue;
1447 }
1448 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
1449 // Unhide the AVP
1450 n = unhide_avp(b, t, s, n);
1451 if (n == 0)
1452 {
1453 fatal = flags;
1454 continue;
1455 }
1456 }
1457 if (*b & 0x3C)
1458 {
1459 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Unrecognised AVP flags %02X\n", *b);
1460 fatal = flags;
1461 continue; // next
1462 }
1463 b += 2;
1464 if (*(u16 *) (b))
1465 {
1466 LOG(2, ntohl(addr->sin_addr.s_addr), s, t, "Unknown AVP vendor %d\n", ntohs(*(u16 *) (b)));
1467 fatal = flags;
1468 continue; // next
1469 }
1470 b += 2;
1471 mtype = ntohs(*(u16 *) (b));
1472 b += 2;
1473 n -= 6;
1474
1475 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " AVP %d (%s) len %d\n", mtype, avpnames[mtype], n);
1476 switch (mtype)
1477 {
1478 case 0: // message type
1479 message = ntohs(*(u16 *) b);
1480 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Message type = %d (%s)\n", *b,
1481 l2tp_message_types[message]);
1482 mandatorymessage = flags;
1483 break;
1484 case 1: // result code
1485 {
1486 u16 rescode = ntohs(*(u16 *)(b));
1487 const char* resdesc = "(unknown)";
1488 if (message == 4)
1489 { /* StopCCN */
1490 if (rescode <= MAX_STOPCCN_RESULT_CODE)
1491 resdesc = stopccn_result_codes[rescode];
1492 }
1493 else if (message == 14)
1494 { /* CDN */
1495 if (rescode <= MAX_CDN_RESULT_CODE)
1496 resdesc = cdn_result_codes[rescode];
1497 }
1498
1499 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Result Code %d: %s\n",
1500 rescode, resdesc);
1501 if (n >= 4)
1502 {
1503 u16 errcode = ntohs(*(u16 *)(b + 2));
1504 const char* errdesc = "(unknown)";
1505 if (errcode <= MAX_ERROR_CODE)
1506 errdesc = error_codes[errcode];
1507 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Error Code %d: %s\n",
1508 errcode, errdesc);
1509 }
1510 if (n > 4)
1511 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Error String: %.*s\n",
1512 n-4, b+4);
1513
1514 break;
1515 }
1516 break;
1517 case 2: // protocol version
1518 {
1519 version = ntohs(*(u16 *) (b));
1520 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Protocol version = %d\n", version);
1521 if (version && version != 0x0100)
1522 { // allow 0.0 and 1.0
1523 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, " Bad protocol version %04X\n",
1524 version);
1525 fatal = flags;
1526 continue; // next
1527 }
1528 }
1529 break;
1530 case 3: // framing capabilities
1531 // LOG(4, ntohl(addr->sin_addr.s_addr), s, t, "Framing capabilities\n");
1532 break;
1533 case 4: // bearer capabilities
1534 // LOG(4, ntohl(addr->sin_addr.s_addr), s, t, "Bearer capabilities\n");
1535 break;
1536 case 5: // tie breaker
1537 // We never open tunnels, so we don't care about tie breakers
1538 // LOG(4, ntohl(addr->sin_addr.s_addr), s, t, "Tie breaker\n");
1539 continue;
1540 case 6: // firmware revision
1541 // LOG(4, ntohl(addr->sin_addr.s_addr), s, t, "Firmware revision\n");
1542 break;
1543 case 7: // host name
1544 memset(tunnel[t].hostname, 0, 128);
1545 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1546 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1547 // TBA - to send to RADIUS
1548 break;
1549 case 8: // vendor name
1550 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
1551 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
1552 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
1553 break;
1554 case 9: // assigned tunnel
1555 tunnel[t].far = ntohs(*(u16 *) (b));
1556 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Remote tunnel id = %d\n", tunnel[t].far);
1557 break;
1558 case 10: // rx window
1559 tunnel[t].window = ntohs(*(u16 *) (b));
1560 if (!tunnel[t].window)
1561 tunnel[t].window = 1; // window of 0 is silly
1562 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " rx window = %d\n", tunnel[t].window);
1563 break;
1564 case 11: // Challenge
1565 {
1566 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " LAC requested CHAP authentication for tunnel\n");
1567 build_chap_response(b, 2, n, &chapresponse);
1568 }
1569 break;
1570 case 13: // Response
1571 // Why did they send a response? We never challenge.
1572 LOG(2, ntohl(addr->sin_addr.s_addr), s, t, " received unexpected challenge response\n");
1573 break;
1574
1575 case 14: // assigned session
1576 asession = session[s].far = ntohs(*(u16 *) (b));
1577 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
1578 break;
1579 case 15: // call serial number
1580 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " call serial number = %d\n", ntohl(*(u32 *)b));
1581 break;
1582 case 18: // bearer type
1583 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " bearer type = %d\n", ntohl(*(u32 *)b));
1584 // TBA - for RADIUS
1585 break;
1586 case 19: // framing type
1587 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " framing type = %d\n", ntohl(*(u32 *)b));
1588 // TBA
1589 break;
1590 case 21: // called number
1591 memset(called, 0, MAXTEL);
1592 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1593 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Called <%s>\n", called);
1594 break;
1595 case 22: // calling number
1596 memset(calling, 0, MAXTEL);
1597 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
1598 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Calling <%s>\n", calling);
1599 break;
1600 case 23: // subtype
1601 break;
1602 case 24: // tx connect speed
1603 if (n == 4)
1604 {
1605 session[s].tx_connect_speed = ntohl(*(u32 *)b);
1606 }
1607 else
1608 {
1609 // AS5300s send connect speed as a string
1610 char tmp[30] = {0};
1611 memcpy(tmp, b, (n >= 30) ? 30 : n);
1612 session[s].tx_connect_speed = atol(tmp);
1613 }
1614 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " TX connect speed <%u>\n",
1615 session[s].tx_connect_speed);
1616 break;
1617 case 38: // rx connect speed
1618 if (n == 4)
1619 {
1620 session[s].rx_connect_speed = ntohl(*(u32 *)b);
1621 }
1622 else
1623 {
1624 // AS5300s send connect speed as a string
1625 char tmp[30] = {0};
1626 memcpy(tmp, b, (n >= 30) ? 30 : n);
1627 session[s].rx_connect_speed = atol(tmp);
1628 }
1629 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " RX connect speed <%u>\n",
1630 session[s].rx_connect_speed);
1631 break;
1632 case 25: // Physical Channel ID
1633 {
1634 u32 tmp = ntohl(*(u32 *)b);
1635 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Physical Channel ID <%X>\n", tmp);
1636 break;
1637 }
1638 case 29: // Proxy Authentication Type
1639 {
1640 u16 authtype = ntohs(*(u16 *)b);
1641 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Type %d (%s)\n",
1642 authtype, authtypes[authtype]);
1643 requestchap = (authtype == 2);
1644 break;
1645 }
1646 case 30: // Proxy Authentication Name
1647 {
1648 char authname[64] = {0};
1649 memcpy(authname, b, (n > 63) ? 63 : n);
1650 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Name (%s)\n",
1651 authname);
1652 break;
1653 }
1654 case 31: // Proxy Authentication Challenge
1655 {
1656 memcpy(radius[session[s].radius].auth, b, 16);
1657 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Challenge\n");
1658 break;
1659 }
1660 case 32: // Proxy Authentication ID
1661 {
1662 u16 authid = ntohs(*(u16 *)(b));
1663 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth ID (%d)\n",
1664 authid);
1665 if (session[s].radius)
1666 radius[session[s].radius].id = authid;
1667 break;
1668 }
1669 case 33: // Proxy Authentication Response
1670 {
1671 char authresp[64] = {0};
1672 memcpy(authresp, b, (n > 63) ? 63 : n);
1673 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Proxy Auth Response\n");
1674 break;
1675 }
1676 case 27: // last send lcp
1677 { // find magic number
1678 u8 *p = b, *e = p + n;
1679 while (p + 1 < e && p[1] && p + p[1] <= e)
1680 {
1681 if (*p == 5 && p[1] == 6) // Magic-Number
1682 amagic = ntohl(*(u32 *) (p + 2));
1683 else if (*p == 3 && p[1] == 5 && *(u16 *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
1684 chap = 1;
1685 else if (*p == 7) // Protocol-Field-Compression
1686 aflags |= SESSIONPFC;
1687 else if (*p == 8) // Address-and-Control-Field-Compression
1688 aflags |= SESSIONACFC;
1689 p += p[1];
1690 }
1691 }
1692 break;
1693 case 28: // last recv lcp confreq
1694 break;
1695 case 26: // Initial Received LCP CONFREQ
1696 break;
1697 case 39: // seq required - we control it as an LNS anyway...
1698 break;
1699 case 36: // Random Vector
1700 LOG(4, ntohl(addr->sin_addr.s_addr), s, t, " Random Vector received. Enabled AVP Hiding.\n");
1701 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
1702 memcpy(session[s].random_vector, b, n);
1703 session[s].random_vector_length = n;
1704 break;
1705 default:
1706 LOG(2, ntohl(addr->sin_addr.s_addr), s, t, " Unknown AVP type %d\n", mtype);
1707 fatal = flags;
1708 continue; // next
1709 }
1710 }
1711 // process message
1712 if (fatal & 0x80)
1713 tunnelshutdown(t, "Unknown Mandatory AVP");
1714 else
1715 switch (message)
1716 {
1717 case 1: // SCCRQ - Start Control Connection Request
1718 {
1719 controlt *c = controlnew(2); // sending SCCRP
1720 control16(c, 2, version, 1); // protocol version
1721 control32(c, 3, 3, 1); // framing
1722 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
1723 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
1724 control16(c, 9, t, 1); // assigned tunnel
1725 controladd(c, t, s); // send the resply
1726 }
1727 tunnel[t].state = TUNNELOPENING;
1728 break;
1729 case 2: // SCCRP
1730 tunnel[t].state = TUNNELOPEN;
1731 break;
1732 case 3: // SCCN
1733 tunnel[t].state = TUNNELOPEN;
1734 controlnull(t); // ack
1735 break;
1736 case 4: // StopCCN
1737 controlnull(t); // ack
1738 tunnelshutdown(t, "Stopped"); // Shut down cleanly
1739 tunnelkill(t, "Stopped"); // Immediately force everything dead
1740 break;
1741 case 6: // HELLO
1742 controlnull(t); // simply ACK
1743 break;
1744 case 7: // OCRQ
1745 // TBA
1746 break;
1747 case 8: // OCRO
1748 // TBA
1749 break;
1750 case 9: // OCCN
1751 // TBA
1752 break;
1753 case 10: // ICRQ
1754 if (!sessionfree)
1755 {
1756 STAT(session_overflow);
1757 tunnelshutdown(t, "No free sessions");
1758 }
1759 else
1760 {
1761 u16 r;
1762 controlt *c;
1763
1764 s = sessionfree;
1765 sessionfree = session[s].next;
1766 memset(&session[s], 0, sizeof(session[s]));
1767
1768 if (s > config->cluster_highest_sessionid)
1769 config->cluster_highest_sessionid = s;
1770
1771 // make a RADIUS session
1772 if (!(r = radiusnew(s)))
1773 {
1774 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "No free RADIUS sessions for ICRQ\n");
1775 sessionkill(s, "no free RADIUS sesions");
1776 return;
1777 }
1778
1779 c = controlnew(11); // sending ICRP
1780 session[s].id = sessionid++;
1781 session[s].opened = time(NULL);
1782 session[s].tunnel = t;
1783 session[s].far = asession;
1784 session[s].last_packet = time_now;
1785 LOG(3, ntohl(addr->sin_addr.s_addr), s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
1786 control16(c, 14, s, 1); // assigned session
1787 controladd(c, t, s); // send the reply
1788 {
1789 // Generate a random challenge
1790 int n;
1791 for (n = 0; n < 15; n++)
1792 radius[r].auth[n] = rand();
1793 }
1794 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
1795 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
1796 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
1797 STAT(session_created);
1798 }
1799 break;
1800 case 11: // ICRP
1801 // TBA
1802 break;
1803 case 12: // ICCN
1804 if (amagic == 0) amagic = time_now;
1805 session[s].magic = amagic; // set magic number
1806 session[s].l2tp_flags = aflags; // set flags received
1807 LOG(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
1808 controlnull(t); // ack
1809 // In CHAP state, request PAP instead
1810 if (requestchap)
1811 initlcp(t, s);
1812 break;
1813 case 14: // CDN
1814 controlnull(t); // ack
1815 sessionshutdown(s, "Closed (Received CDN)");
1816 break;
1817 case 0xFFFF:
1818 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Missing message type\n");
1819 break;
1820 default:
1821 STAT(tunnel_rx_errors);
1822 if (mandatorymessage & 0x80)
1823 tunnelshutdown(t, "Unknown message");
1824 else
1825 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown message type %d\n", message);
1826 break;
1827 }
1828 if (chapresponse) free(chapresponse);
1829 cluster_send_tunnel(t);
1830 }
1831 else
1832 {
1833 LOG(4, 0, s, t, " Got a ZLB ack\n");
1834 }
1835 }
1836 else
1837 { // data
1838 u16 prot;
1839
1840 LOG_HEX(5, "Receive Tunnel Data", p, l);
1841 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
1842 { // HDLC address header, discard
1843 p += 2;
1844 l -= 2;
1845 }
1846 if (l < 2)
1847 {
1848 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Short ppp length %d\n", l);
1849 STAT(tunnel_rx_errors);
1850 return;
1851 }
1852 if (*p & 1)
1853 {
1854 prot = *p++;
1855 l--;
1856 }
1857 else
1858 {
1859 prot = ntohs(*(u16 *) p);
1860 p += 2;
1861 l -= 2;
1862 }
1863
1864 if (s && !session[s].tunnel) // Is something wrong??
1865 {
1866 if (!config->cluster_iam_master)
1867 {
1868 // Pass it off to the master to deal with..
1869 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1870 return;
1871 }
1872
1873
1874 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "UDP packet contains session %d "
1875 "but no session[%d].tunnel exists (LAC said"
1876 " tunnel = %d). Dropping packet.\n", s, s, t);
1877 STAT(tunnel_rx_errors);
1878 return;
1879 }
1880
1881 if (session[s].die)
1882 {
1883 LOG(3, ntohl(addr->sin_addr.s_addr), s, t, "Session %d is closing. Don't process PPP packets\n", s);
1884 // I'm pretty sure this isn't right -- mo.
1885 // return; // closing session, PPP not processed
1886 }
1887 if (prot == PPPPAP)
1888 {
1889 session[s].last_packet = time_now;
1890 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1891 processpap(t, s, p, l);
1892 }
1893 else if (prot == PPPCHAP)
1894 {
1895 session[s].last_packet = time_now;
1896 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1897 processchap(t, s, p, l);
1898 }
1899 else if (prot == PPPLCP)
1900 {
1901 session[s].last_packet = time_now;
1902 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1903 processlcp(t, s, p, l);
1904 }
1905 else if (prot == PPPIPCP)
1906 {
1907 session[s].last_packet = time_now;
1908 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1909 processipcp(t, s, p, l);
1910 }
1911 else if (prot == PPPCCP)
1912 {
1913 session[s].last_packet = time_now;
1914 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
1915 processccp(t, s, p, l);
1916 }
1917 else if (prot == PPPIP)
1918 {
1919 session[s].last_packet = time_now;
1920 if (session[s].walled_garden && !config->cluster_iam_master)
1921 {
1922 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1923 return;
1924 }
1925 processipin(t, s, p, l);
1926 }
1927 else
1928 {
1929 STAT(tunnel_rx_errors);
1930 LOG(1, ntohl(addr->sin_addr.s_addr), s, t, "Unknown PPP protocol %04X\n", prot);
1931 }
1932 }
1933 }
1934
1935 // read and process packet on tun
1936 static void processtun(u8 * buf, int len)
1937 {
1938 LOG_HEX(5, "Receive TUN Data", buf, len);
1939 STAT(tun_rx_packets);
1940 INC_STAT(tun_rx_bytes, len);
1941
1942 CSTAT(call_processtun);
1943
1944 eth_rx_pkt++;
1945 eth_rx += len;
1946 if (len < 22)
1947 {
1948 LOG(1, 0, 0, 0, "Short tun packet %d bytes\n", len);
1949 STAT(tun_rx_errors);
1950 return;
1951 }
1952
1953 if (*(u16 *) (buf + 2) == htons(PKTIP)) // IP
1954 processipout(buf, len);
1955 // Else discard.
1956 }
1957
1958 //
1959 // Maximum number of actions to complete.
1960 // This is to avoid sending out too many packets
1961 // at once.
1962 #define MAX_ACTIONS 500
1963
1964 static int regular_cleanups(void)
1965 {
1966 static sessionidt s = 0; // Next session to check for actions on.
1967 tunnelidt t;
1968 int count=0,i;
1969 u16 r;
1970 static clockt next_acct = 0;
1971 int a;
1972
1973 LOG(3, 0, 0, 0, "Begin regular cleanup\n");
1974
1975 for (r = 1; r < MAXRADIUS; r++)
1976 {
1977 if (!radius[r].state)
1978 continue;
1979 if (radius[r].retry)
1980 {
1981 if (radius[r].retry <= TIME)
1982 radiusretry(r);
1983 } else
1984 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
1985 }
1986 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
1987 {
1988 // check for expired tunnels
1989 if (tunnel[t].die && tunnel[t].die <= TIME)
1990 {
1991 STAT(tunnel_timeout);
1992 tunnelkill(t, "Expired");
1993 continue;
1994 }
1995 // check for message resend
1996 if (tunnel[t].retry && tunnel[t].controlc)
1997 {
1998 // resend pending messages as timeout on reply
1999 if (tunnel[t].retry <= TIME)
2000 {
2001 controlt *c = tunnel[t].controls;
2002 u8 w = tunnel[t].window;
2003 tunnel[t].try++; // another try
2004 if (tunnel[t].try > 5)
2005 tunnelkill(t, "Timeout on control message"); // game over
2006 else
2007 while (c && w--)
2008 {
2009 tunnelsend(c->buf, c->length, t);
2010 c = c->next;
2011 }
2012 }
2013 }
2014 // Send hello
2015 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2016 {
2017 controlt *c = controlnew(6); // sending HELLO
2018 controladd(c, t, 0); // send the message
2019 LOG(3, tunnel[t].ip, 0, t, "Sending HELLO message\n");
2020 }
2021
2022 // Check for tunnel changes requested from the CLI
2023 if ((a = cli_tunnel_actions[t].action))
2024 {
2025 cli_tunnel_actions[t].action = 0;
2026 if (a & CLI_TUN_KILL)
2027 {
2028 LOG(2, tunnel[t].ip, 0, t, "Dropping tunnel by CLI\n");
2029 tunnelshutdown(t, "Requested by administrator");
2030 }
2031 }
2032
2033 }
2034
2035 count = 0;
2036 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2037 {
2038 s++;
2039 if (s > config->cluster_highest_sessionid)
2040 s = 1;
2041
2042 if (!session[s].tunnel) // Session isn't in use
2043 continue;
2044
2045 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2046 {
2047 // IPCP has not completed yet. Resend
2048 LOG(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2049 sendipcp(session[s].tunnel, s);
2050 }
2051
2052 // check for expired sessions
2053 if (session[s].die && session[s].die <= TIME)
2054 {
2055 sessionkill(s, "Expired");
2056 if (++count >= MAX_ACTIONS) break;
2057 continue;
2058 }
2059
2060 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2061 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2062 {
2063 sessionkill(s, "No response to LCP ECHO requests");
2064 STAT(session_timeout);
2065 if (++count >= MAX_ACTIONS) break;
2066 continue;
2067 }
2068
2069 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2070 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2071 {
2072 u8 b[MAXCONTROL] = {0};
2073
2074 u8 *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2075 if (!q) continue;
2076
2077 *q = EchoReq;
2078 *(u8 *)(q + 1) = (time_now % 255); // ID
2079 *(u16 *)(q + 2) = htons(8); // Length
2080 *(u32 *)(q + 4) = 0; // Magic Number (not supported)
2081
2082 LOG(4, session[s].ip, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2083 (int)(time_now - session[s].last_packet));
2084 tunnelsend(b, 24, session[s].tunnel); // send it
2085 if (++count >= MAX_ACTIONS) break;
2086 }
2087
2088 // Check for actions requested from the CLI
2089 if ((a = cli_session_actions[s].action))
2090 {
2091 int send = 0;
2092
2093 cli_session_actions[s].action = 0;
2094 if (a & CLI_SESS_KILL)
2095 {
2096 LOG(2, 0, s, session[s].tunnel, "Dropping session by CLI\n");
2097 sessionshutdown(s, "Requested by administrator");
2098 a = 0; // dead, no need to check for other actions
2099 }
2100
2101 if (a & CLI_SESS_NOSNOOP)
2102 {
2103 LOG(2, 0, s, session[s].tunnel, "Unsnooping session by CLI\n");
2104 session[s].snoop_ip = 0;
2105 session[s].snoop_port = 0;
2106 send++;
2107 }
2108 else if (a & CLI_SESS_SNOOP)
2109 {
2110 LOG(2, 0, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2111 inet_toa(cli_session_actions[s].snoop_ip), cli_session_actions[s].snoop_port);
2112
2113 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2114 session[s].snoop_port = cli_session_actions[s].snoop_port;
2115 send++;
2116 }
2117
2118 if (a & CLI_SESS_NOTHROTTLE)
2119 {
2120 LOG(2, 0, s, session[s].tunnel, "Un-throttling session by CLI\n");
2121 throttle_session(s, 0, 0);
2122 send++;
2123 }
2124 else if (a & CLI_SESS_THROTTLE)
2125 {
2126 LOG(2, 0, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2127 cli_session_actions[s].throttle_in,
2128 cli_session_actions[s].throttle_out);
2129
2130 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2131 send++;
2132 }
2133
2134 if (send)
2135 cluster_send_session(s);
2136
2137 if (++count >= MAX_ACTIONS) break;
2138 }
2139 }
2140
2141 if (*config->accounting_dir && next_acct <= TIME)
2142 {
2143 // Dump accounting data
2144 next_acct = TIME + ACCT_TIME;
2145 dump_acct_info();
2146 }
2147
2148 if (count >= MAX_ACTIONS)
2149 return 1; // Didn't finish!
2150
2151 LOG(3, 0, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2152 return 0;
2153 }
2154
2155
2156 //
2157 // Are we in the middle of a tunnel update, or radius
2158 // requests??
2159 //
2160 static int still_busy(void)
2161 {
2162 int i;
2163 static clockt last_talked = 0;
2164 static clockt start_busy_wait = 0;
2165 if (start_busy_wait == 0)
2166 start_busy_wait = TIME;
2167
2168 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2169 {
2170 if (!tunnel[i].controlc)
2171 continue;
2172
2173 if (last_talked != TIME)
2174 {
2175 LOG(2,0,0,0, "Tunnel %d still has un-acked control messages.\n", i);
2176 last_talked = TIME;
2177 }
2178 return 1;
2179 }
2180
2181 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2182 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2183 {
2184 LOG(1, 0, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2185 return 0;
2186 }
2187
2188 for (i = 1; i < MAXRADIUS; i++)
2189 {
2190 if (radius[i].state == RADIUSNULL)
2191 continue;
2192 if (radius[i].state == RADIUSWAIT)
2193 continue;
2194
2195 if (last_talked != TIME)
2196 {
2197 LOG(2,0,0,0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2198 last_talked = TIME;
2199 }
2200 return 1;
2201 }
2202
2203 return 0;
2204 }
2205
2206 static fd_set readset;
2207 static int readset_n = 0;
2208
2209 // main loop - gets packets on tun or udp and processes them
2210 static void mainloop(void)
2211 {
2212 int i;
2213 u8 buf[65536];
2214 struct timeval to;
2215 clockt next_cluster_ping = 0; // send initial ping immediately
2216 time_t next_clean = time_now + config->cleanup_interval;
2217
2218 LOG(4, 0, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2219 udpfd, tunfd, cluster_sockfd, controlfd);
2220
2221 FD_ZERO(&readset);
2222 FD_SET(udpfd, &readset);
2223 FD_SET(tunfd, &readset);
2224 FD_SET(controlfd, &readset);
2225 FD_SET(clifd, &readset);
2226 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2227 readset_n = udpfd;
2228 if (tunfd > readset_n) readset_n = tunfd;
2229 if (controlfd > readset_n) readset_n = controlfd;
2230 if (clifd > readset_n) readset_n = clifd;
2231 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2232
2233 while (!main_quit || still_busy())
2234 {
2235 fd_set r;
2236 int n = readset_n;
2237 #ifdef BGP
2238 fd_set w;
2239 int bgp_set[BGP_NUM_PEERS];
2240 #endif /* BGP */
2241
2242 if (config->reload_config)
2243 {
2244 // Update the config state based on config settings
2245 update_config();
2246 }
2247
2248 memcpy(&r, &readset, sizeof(fd_set));
2249 to.tv_sec = 0;
2250 to.tv_usec = 100000; // 1/10th of a second.
2251
2252 #ifdef BGP
2253 FD_ZERO(&w);
2254 for (i = 0; i < BGP_NUM_PEERS; i++)
2255 {
2256 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2257 if (bgp_set[i] & 1)
2258 {
2259 FD_SET(bgp_peers[i].sock, &r);
2260 if (bgp_peers[i].sock > n)
2261 n = bgp_peers[i].sock;
2262 }
2263
2264 if (bgp_set[i] & 2)
2265 {
2266 FD_SET(bgp_peers[i].sock, &w);
2267 if (bgp_peers[i].sock > n)
2268 n = bgp_peers[i].sock;
2269 }
2270 }
2271
2272 n = select(n + 1, &r, &w, 0, &to);
2273 #else /* BGP */
2274 n = select(n + 1, &r, 0, 0, &to);
2275 #endif /* BGP */
2276
2277 TIME = now();
2278 if (n < 0)
2279 {
2280 if (errno == EINTR ||
2281 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2282 continue;
2283
2284 LOG(0, 0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2285 main_quit++;
2286 break;
2287 }
2288 else if (n)
2289 {
2290 struct sockaddr_in addr;
2291 int alen = sizeof(addr);
2292 if (FD_ISSET(udpfd, &r))
2293 {
2294 int c, n;
2295 for (c = 0; c < config->multi_read_count; c++)
2296 {
2297 if ((n = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2298 processudp(buf, n, &addr);
2299 else
2300 break;
2301 }
2302 }
2303 if (FD_ISSET(tunfd, &r))
2304 {
2305 int c, n;
2306 for (c = 0; c < config->multi_read_count; c++)
2307 {
2308 if ((n = read(tunfd, buf, sizeof(buf))) > 0)
2309 processtun(buf, n);
2310 else
2311 break;
2312 }
2313 }
2314
2315 if (config->cluster_iam_master)
2316 for (i = 0; i < config->num_radfds; i++)
2317 if (FD_ISSET(radfds[i], &r))
2318 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2319
2320 if (FD_ISSET(cluster_sockfd, &r))
2321 {
2322 int size;
2323 size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
2324 processcluster(buf, size, addr.sin_addr.s_addr);
2325 }
2326
2327 if (FD_ISSET(controlfd, &r))
2328 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2329
2330 if (FD_ISSET(clifd, &r))
2331 {
2332 struct sockaddr_in addr;
2333 int sockfd;
2334 int len = sizeof(addr);
2335
2336 if ((sockfd = accept(clifd, (struct sockaddr *)&addr, &len)) <= 0)
2337 {
2338 LOG(0, 0, 0, 0, "accept error: %s\n", strerror(errno));
2339 continue;
2340 }
2341 else
2342 {
2343 cli_do(sockfd);
2344 close(sockfd);
2345 }
2346 }
2347 }
2348
2349 // Runs on every machine (master and slaves).
2350 if (cluster_sockfd && next_cluster_ping <= TIME)
2351 {
2352 // Check to see which of the cluster is still alive..
2353
2354 cluster_send_ping(basetime); // Only does anything if we're a slave
2355 cluster_check_master(); // ditto.
2356
2357 cluster_heartbeat(); // Only does anything if we're a master.
2358 cluster_check_slaves(); // ditto.
2359
2360 master_update_counts(); // If we're a slave, send our byte counters to our master.
2361
2362 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2363 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2364 else
2365 next_cluster_ping = TIME + config->cluster_hb_interval;
2366 }
2367
2368 // Run token bucket filtering queue..
2369 // Only run it every 1/10th of a second.
2370 // Runs on all machines both master and slave.
2371 {
2372 static clockt last_run = 0;
2373 if (last_run != TIME)
2374 {
2375 last_run = TIME;
2376 tbf_run_timer();
2377 }
2378 }
2379
2380 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2381 * something to read, else under load this will never actually run....
2382 *
2383 */
2384 if (config->cluster_iam_master && next_clean <= time_now)
2385 {
2386 if (regular_cleanups())
2387 {
2388 // Did it finish?
2389 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2390 }
2391 else
2392 {
2393 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2394 }
2395 }
2396
2397 #ifdef BGP
2398 for (i = 0; i < BGP_NUM_PEERS; i++)
2399 {
2400 bgp_process(&bgp_peers[i],
2401 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0,
2402 bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0);
2403 }
2404 #endif /* BGP */
2405 }
2406
2407 // Are we the master and shutting down??
2408 if (config->cluster_iam_master)
2409 cluster_heartbeat(); // Flush any queued changes..
2410
2411 // Ok. Notify everyone we're shutting down. If we're
2412 // the master, this will force an election.
2413 cluster_send_ping(0);
2414
2415 //
2416 // Important!!! We MUST not process any packets past this point!
2417 }
2418
2419 static void stripdomain(char *host)
2420 {
2421 char *p;
2422
2423 if ((p = strchr(host, '.')))
2424 {
2425 char *domain = 0;
2426 char _domain[1024];
2427
2428 // strip off domain
2429 FILE *resolv = fopen("/etc/resolv.conf", "r");
2430 if (resolv)
2431 {
2432 char buf[1024];
2433 char *b;
2434
2435 while (fgets(buf, sizeof(buf), resolv))
2436 {
2437 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
2438 continue;
2439
2440 if (!isspace(buf[6]))
2441 continue;
2442
2443 b = buf + 7;
2444 while (isspace(*b)) b++;
2445
2446 if (*b)
2447 {
2448 char *d = b;
2449 while (*b && !isspace(*b)) b++;
2450 *b = 0;
2451 if (buf[0] == 'd') // domain is canonical
2452 {
2453 domain = d;
2454 break;
2455 }
2456
2457 // first search line
2458 if (!domain)
2459 {
2460 // hold, may be subsequent domain line
2461 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
2462 domain = _domain;
2463 }
2464 }
2465 }
2466
2467 fclose(resolv);
2468 }
2469
2470 if (domain)
2471 {
2472 int hl = strlen(host);
2473 int dl = strlen(domain);
2474 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
2475 host[hl -dl - 1] = 0;
2476 }
2477 else
2478 {
2479 *p = 0; // everything after first dot
2480 }
2481 }
2482 }
2483
2484 // Init data structures
2485 static void initdata(int optdebug, char *optconfig)
2486 {
2487 int i;
2488
2489 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
2490 {
2491 LOG(0, 0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
2492 exit(1);
2493 }
2494 if (!(config = shared_malloc(sizeof(configt))))
2495 {
2496 LOG(0, 0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
2497 exit(1);
2498 }
2499 memset(config, 0, sizeof(configt));
2500 time(&config->start_time);
2501 strncpy(config->config_file, optconfig, strlen(optconfig));
2502 config->debug = optdebug;
2503 config->num_tbfs = MAXTBFS;
2504 config->rl_rate = 28; // 28kbps
2505
2506 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
2507 {
2508 LOG(0, 0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
2509 exit(1);
2510 }
2511 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
2512 {
2513 LOG(0, 0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
2514 exit(1);
2515 }
2516
2517 if (!(sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)))
2518 {
2519 LOG(0, 0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
2520 exit(1);
2521 }
2522
2523 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
2524 {
2525 LOG(0, 0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
2526 exit(1);
2527 }
2528
2529 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
2530 {
2531 LOG(0, 0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
2532 exit(1);
2533 }
2534
2535 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
2536 {
2537 LOG(0, 0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
2538 exit(1);
2539 }
2540 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
2541
2542 #ifdef RINGBUFFER
2543 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
2544 {
2545 LOG(0, 0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
2546 exit(1);
2547 }
2548 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
2549 #endif
2550
2551 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
2552 {
2553 LOG(0, 0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
2554 exit(1);
2555 }
2556 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
2557
2558 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
2559 {
2560 LOG(0, 0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
2561 exit(1);
2562 }
2563 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
2564
2565 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
2566 memset(session, 0, sizeof(sessiont) * MAXSESSION);
2567 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
2568 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
2569
2570 // Put all the sessions on the free list marked as undefined.
2571 for (i = 1; i < MAXSESSION - 1; i++)
2572 {
2573 session[i].next = i + 1;
2574 session[i].tunnel = T_UNDEF; // mark it as not filled in.
2575 }
2576 session[MAXSESSION - 1].next = 0;
2577 sessionfree = 1;
2578
2579 // Mark all the tunnels as undefined (waiting to be filled in by a download).
2580 for (i = 1; i < MAXTUNNEL- 1; i++)
2581 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
2582
2583 if (!*hostname)
2584 {
2585 // Grab my hostname unless it's been specified
2586 gethostname(hostname, sizeof(hostname));
2587 stripdomain(hostname);
2588 }
2589
2590 _statistics->start_time = _statistics->last_reset = time(NULL);
2591
2592 #ifdef BGP
2593 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
2594 {
2595 LOG(0, 0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
2596 exit(1);
2597 }
2598 #endif /* BGP */
2599 }
2600
2601 static int assign_ip_address(sessionidt s)
2602 {
2603 u32 i;
2604 int best = -1;
2605 time_t best_time = time_now;
2606 char *u = session[s].user;
2607 char reuse = 0;
2608
2609
2610 CSTAT(call_assign_ip_address);
2611
2612 for (i = 1; i < ip_pool_size; i++)
2613 {
2614 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
2615 continue;
2616
2617 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
2618 {
2619 best = i;
2620 reuse = 1;
2621 break;
2622 }
2623
2624 if (ip_address_pool[i].last < best_time)
2625 {
2626 best = i;
2627 if (!(best_time = ip_address_pool[i].last))
2628 break; // never used, grab this one
2629 }
2630 }
2631
2632 if (best < 0)
2633 {
2634 LOG(0, 0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
2635 return 0;
2636 }
2637
2638 session[s].ip = ip_address_pool[best].address;
2639 session[s].ip_pool_index = best;
2640 ip_address_pool[best].assigned = 1;
2641 ip_address_pool[best].last = time_now;
2642 ip_address_pool[best].session = s;
2643 if (session[s].walled_garden)
2644 /* Don't track addresses of users in walled garden (note: this
2645 means that their address isn't "sticky" even if they get
2646 un-gardened). */
2647 ip_address_pool[best].user[0] = 0;
2648 else
2649 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
2650
2651 STAT(ip_allocated);
2652 LOG(4, ip_address_pool[best].address, s, session[s].tunnel,
2653 "assign_ip_address(): %s ip address %d from pool\n", reuse ? "Reusing" : "Allocating", best);
2654
2655 return 1;
2656 }
2657
2658 static void free_ip_address(sessionidt s)
2659 {
2660 int i = session[s].ip_pool_index;
2661
2662
2663 CSTAT(call_free_ip_address);
2664
2665 if (!session[s].ip)
2666 return; // what the?
2667
2668 if (i < 0) // Is this actually part of the ip pool?
2669 i = 0;
2670
2671 STAT(ip_freed);
2672 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
2673 session[s].ip = 0;
2674 ip_address_pool[i].assigned = 0;
2675 ip_address_pool[i].session = 0;
2676 ip_address_pool[i].last = time_now;
2677 }
2678
2679 //
2680 // Fsck the address pool against the session table.
2681 // Normally only called when we become a master.
2682 //
2683 // This isn't perfect: We aren't keep tracking of which
2684 // users used to have an IP address.
2685 //
2686 void rebuild_address_pool(void)
2687 {
2688 int i;
2689
2690 //
2691 // Zero the IP pool allocation, and build
2692 // a map from IP address to pool index.
2693 for (i = 1; i < MAXIPPOOL; ++i)
2694 {
2695 ip_address_pool[i].assigned = 0;
2696 ip_address_pool[i].session = 0;
2697 if (!ip_address_pool[i].address)
2698 continue;
2699
2700 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
2701 }
2702
2703 for (i = 0; i < MAXSESSION; ++i)
2704 {
2705 int ipid;
2706 if (!session[i].ip || !session[i].tunnel)
2707 continue;
2708 ipid = - lookup_ipmap(htonl(session[i].ip));
2709
2710 if (session[i].ip_pool_index < 0)
2711 {
2712 // Not allocated out of the pool.
2713 if (ipid < 1) // Not found in the pool either? good.
2714 continue;
2715
2716 LOG(0, 0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
2717 i, inet_toa(session[i].ip), ipid);
2718
2719 // Fall through and process it as part of the pool.
2720 }
2721
2722
2723 if (ipid > MAXIPPOOL || ipid < 0)
2724 {
2725 LOG(0, 0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
2726 ipid = -1;
2727 session[i].ip_pool_index = ipid;
2728 continue;
2729 }
2730
2731 ip_address_pool[ipid].assigned = 1;
2732 ip_address_pool[ipid].session = i;
2733 ip_address_pool[ipid].last = time_now;
2734 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
2735 session[i].ip_pool_index = ipid;
2736 cache_ipmap(session[i].ip, i); // Fix the ip map.
2737 }
2738 }
2739
2740 //
2741 // Fix the address pool to match a changed session.
2742 // (usually when the master sends us an update).
2743 static void fix_address_pool(int sid)
2744 {
2745 int ipid;
2746
2747 ipid = session[sid].ip_pool_index;
2748
2749 if (ipid > ip_pool_size)
2750 return; // Ignore it. rebuild_address_pool will fix it up.
2751
2752 if (ip_address_pool[ipid].address != session[sid].ip)
2753 return; // Just ignore it. rebuild_address_pool will take care of it.
2754
2755 ip_address_pool[ipid].assigned = 1;
2756 ip_address_pool[ipid].session = sid;
2757 ip_address_pool[ipid].last = time_now;
2758 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
2759 }
2760
2761 //
2762 // Add a block of addresses to the IP pool to hand out.
2763 //
2764 static void add_to_ip_pool(u32 addr, u32 mask)
2765 {
2766 int i;
2767 if (mask == 0)
2768 mask = 0xffffffff; // Host route only.
2769
2770 addr &= mask;
2771
2772 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
2773 return ;
2774
2775 for (i = addr ;(i & mask) == addr; ++i)
2776 {
2777 if ((i & 0xff) == 0 || (i&0xff) == 255)
2778 continue; // Skip 0 and broadcast addresses.
2779
2780 ip_address_pool[ip_pool_size].address = i;
2781 ip_address_pool[ip_pool_size].assigned = 0;
2782 ++ip_pool_size;
2783 if (ip_pool_size >= MAXIPPOOL)
2784 {
2785 LOG(0,0,0,0, "Overflowed IP pool adding %s\n", inet_toa(htonl(addr)) );
2786 return;
2787 }
2788 }
2789 }
2790
2791 // Initialize the IP address pool
2792 static void initippool()
2793 {
2794 FILE *f;
2795 char *p;
2796 char buf[4096];
2797 memset(ip_address_pool, 0, sizeof(ip_address_pool));
2798
2799 if (!(f = fopen(IPPOOLFILE, "r")))
2800 {
2801 LOG(0, 0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
2802 exit(1);
2803 }
2804
2805 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
2806 {
2807 char *pool = buf;
2808 buf[4095] = 0; // Force it to be zero terminated/
2809
2810 if (*buf == '#' || *buf == '\n')
2811 continue; // Skip comments / blank lines
2812 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
2813 if ((p = (char *)strchr(buf, ':')))
2814 {
2815 ipt src;
2816 *p = '\0';
2817 src = inet_addr(buf);
2818 if (src == INADDR_NONE)
2819 {
2820 LOG(0, 0, 0, 0, "Invalid address pool IP %s\n", buf);
2821 exit(1);
2822 }
2823 // This entry is for a specific IP only
2824 if (src != config->bind_address)
2825 continue;
2826 *p = ':';
2827 pool = p+1;
2828 }
2829 if ((p = (char *)strchr(pool, '/')))
2830 {
2831 // It's a range
2832 int numbits = 0;
2833 u32 start = 0, mask = 0;
2834
2835 LOG(2, 0, 0, 0, "Adding IP address range %s\n", buf);
2836 *p++ = 0;
2837 if (!*p || !(numbits = atoi(p)))
2838 {
2839 LOG(0, 0, 0, 0, "Invalid pool range %s\n", buf);
2840 continue;
2841 }
2842 start = ntohl(inet_addr(pool));
2843 mask = (u32)(pow(2, numbits) - 1) << (32 - numbits);
2844
2845 // Add a static route for this pool
2846 LOG(5, 0, 0, 0, "Adding route for address pool %s/%u\n", inet_toa(htonl(start)), 32 + mask);
2847 routeset(0, start, mask, 0, 1);
2848
2849 add_to_ip_pool(start, mask);
2850 }
2851 else
2852 {
2853 // It's a single ip address
2854 add_to_ip_pool(inet_addr(pool), 0);
2855 }
2856 }
2857 fclose(f);
2858 LOG(1, 0, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
2859 }
2860
2861 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port)
2862 {
2863 struct sockaddr_in snoop_addr = {0};
2864 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
2865 return;
2866
2867 snoop_addr.sin_family = AF_INET;
2868 snoop_addr.sin_addr.s_addr = destination;
2869 snoop_addr.sin_port = ntohs(port);
2870
2871 LOG(5, 0, 0, 0, "Snooping packet at %p (%d bytes) to %s:%d\n",
2872 packet, size, inet_toa(snoop_addr.sin_addr.s_addr), htons(snoop_addr.sin_port));
2873 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
2874 LOG(0, 0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
2875 STAT(packets_snooped);
2876 }
2877
2878 static void dump_acct_info()
2879 {
2880 char filename[1024];
2881 char timestr[64];
2882 time_t t = time(NULL);
2883 int i;
2884 FILE *f = NULL;
2885
2886
2887 CSTAT(call_dump_acct_info);
2888
2889 strftime(timestr, 64, "%Y%m%d%H%M%S", localtime(&t));
2890 snprintf(filename, 1024, "%s/%s", config->accounting_dir, timestr);
2891
2892 for (i = 0; i < MAXSESSION; i++)
2893 {
2894 if (!session[i].opened || !session[i].ip || !(session[i].cin || session[i].cout) || !*session[i].user || session[i].walled_garden)
2895 continue;
2896 if (!f)
2897 {
2898 time_t now = time(NULL);
2899 if (!(f = fopen(filename, "w")))
2900 {
2901 LOG(0, 0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
2902 return ;
2903 }
2904 LOG(3, 0, 0, 0, "Dumping accounting information to %s\n", filename);
2905 fprintf(f, "# dslwatch.pl dump file V1.01\n"
2906 "# host: %s\n"
2907 "# time: %ld\n"
2908 "# uptime: %ld\n"
2909 "# format: username ip qos uptxoctets downrxoctets\n",
2910 hostname,
2911 now,
2912 now - basetime);
2913 }
2914
2915 LOG(4, 0, 0, 0, "Dumping accounting information for %s\n", session[i].user);
2916 fprintf(f, "%s %s %d %u %u\n",
2917 session[i].user, // username
2918 inet_toa(htonl(session[i].ip)), // ip
2919 (session[i].throttle_in || session[i].throttle_out) ? 2 : 1, // qos
2920 (u32)session[i].cin, // uptxoctets
2921 (u32)session[i].cout); // downrxoctets
2922
2923 session[i].pin = session[i].cin = 0;
2924 session[i].pout = session[i].cout = 0;
2925 }
2926
2927 if (f)
2928 fclose(f);
2929 }
2930
2931 // Main program
2932 int main(int argc, char *argv[])
2933 {
2934 int i;
2935 int optdebug = 0;
2936 char *optconfig = CONFIGFILE;
2937
2938 time(&basetime); // start clock
2939
2940 // scan args
2941 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
2942 {
2943 switch (i)
2944 {
2945 case 'd':
2946 if (fork()) exit(0);
2947 setsid();
2948 freopen("/dev/null", "r", stdin);
2949 freopen("/dev/null", "w", stdout);
2950 freopen("/dev/null", "w", stderr);
2951 break;
2952 case 'v':
2953 optdebug++;
2954 break;
2955 case 'c':
2956 optconfig = optarg;
2957 break;
2958 case 'h':
2959 snprintf(hostname, sizeof(hostname), "%s", optarg);
2960 break;
2961 default:
2962 printf("Args are:\n"
2963 "\t-d\t\tDetach from terminal\n"
2964 "\t-c <file>\tConfig file\n"
2965 "\t-h <hostname>\tForce hostname\n"
2966 "\t-v\t\tDebug\n");
2967
2968 return (0);
2969 break;
2970 }
2971 }
2972
2973 // Start the timer routine off
2974 time(&time_now);
2975 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
2976 signal(SIGALRM, sigalrm_handler);
2977 siginterrupt(SIGALRM, 0);
2978
2979 initplugins();
2980 initdata(optdebug, optconfig);
2981
2982 init_cli(hostname);
2983 read_config_file();
2984 init_tbf(config->num_tbfs);
2985
2986 LOG(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
2987 LOG(0, 0, 0, 0, "Copyright (c) 2003, 2004 Optus Internet Engineering\n");
2988 LOG(0, 0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
2989 {
2990 struct rlimit rlim;
2991 rlim.rlim_cur = RLIM_INFINITY;
2992 rlim.rlim_max = RLIM_INFINITY;
2993 // Remove the maximum core size
2994 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
2995 LOG(0, 0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
2996 // Make core dumps go to /tmp
2997 chdir("/tmp");
2998 }
2999
3000 if (config->scheduler_fifo)
3001 {
3002 int ret;
3003 struct sched_param params = {0};
3004 params.sched_priority = 1;
3005
3006 if (get_nprocs() < 2)
3007 {
3008 LOG(0, 0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3009 config->scheduler_fifo = 0;
3010 }
3011 else
3012 {
3013 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3014 {
3015 LOG(1, 0, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3016 }
3017 else
3018 {
3019 LOG(0, 0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3020 config->scheduler_fifo = 0;
3021 }
3022 }
3023 }
3024
3025 /* Set up the cluster communications port. */
3026 if (cluster_init() < 0)
3027 exit(1);
3028
3029 #ifdef BGP
3030 signal(SIGPIPE, SIG_IGN);
3031 bgp_setup(config->as_number);
3032 bgp_add_route(config->bind_address, 0xffffffff);
3033 for (i = 0; i < BGP_NUM_PEERS; i++)
3034 {
3035 if (config->neighbour[i].name[0])
3036 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3037 config->neighbour[i].as, config->neighbour[i].keepalive,
3038 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3039 }
3040 #endif /* BGP */
3041
3042 inittun();
3043 LOG(1, 0, 0, 0, "Set up on interface %s\n", config->tundevice);
3044
3045 initudp();
3046 initrad();
3047 initippool();
3048
3049 read_state();
3050
3051 signal(SIGHUP, sighup_handler);
3052 signal(SIGTERM, sigterm_handler);
3053 signal(SIGINT, sigterm_handler);
3054 signal(SIGQUIT, sigquit_handler);
3055 signal(SIGCHLD, sigchild_handler);
3056
3057 // Prevent us from getting paged out
3058 if (config->lock_pages)
3059 {
3060 if (!mlockall(MCL_CURRENT))
3061 LOG(1, 0, 0, 0, "Locking pages into memory\n");
3062 else
3063 LOG(0, 0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3064 }
3065
3066 alarm(1);
3067
3068 // Drop privileges here
3069 if (config->target_uid > 0 && geteuid() == 0)
3070 setuid(config->target_uid);
3071
3072 mainloop();
3073
3074 #ifdef BGP
3075 /* try to shut BGP down cleanly; with luck the sockets will be
3076 writable since we're out of the select */
3077 for (i = 0; i < BGP_NUM_PEERS; i++)
3078 if (bgp_peers[i].state == Established)
3079 bgp_stop(&bgp_peers[i]);
3080 #endif /* BGP */
3081
3082 /* remove plugins (so cleanup code gets run) */
3083 plugins_done();
3084
3085 // Remove the PID file if we wrote it
3086 if (config->wrote_pid && *config->pid_file == '/')
3087 unlink(config->pid_file);
3088
3089 /* kill CLI children */
3090 signal(SIGTERM, SIG_IGN);
3091 kill(0, SIGTERM);
3092 return 0;
3093 }
3094
3095 static void sighup_handler(int sig)
3096 {
3097 if (log_stream && log_stream != stderr)
3098 {
3099 fclose(log_stream);
3100 log_stream = NULL;
3101 }
3102
3103 read_config_file();
3104 }
3105
3106 static void sigalrm_handler(int sig)
3107 {
3108 // Log current traffic stats
3109
3110 snprintf(config->bandwidth, sizeof(config->bandwidth),
3111 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3112 (udp_rx / 1024.0 / 1024.0 * 8),
3113 (eth_tx / 1024.0 / 1024.0 * 8),
3114 (eth_rx / 1024.0 / 1024.0 * 8),
3115 (udp_tx / 1024.0 / 1024.0 * 8),
3116 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3117 udp_rx_pkt, eth_rx_pkt);
3118
3119 udp_tx = udp_rx = 0;
3120 udp_rx_pkt = eth_rx_pkt = 0;
3121 eth_tx = eth_rx = 0;
3122
3123 if (config->dump_speed)
3124 printf("%s\n", config->bandwidth);
3125
3126 // Update the internal time counter
3127 time(&time_now);
3128 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3129 alarm(1);
3130
3131 {
3132 // Run timer hooks
3133 struct param_timer p = { time_now };
3134 run_plugins(PLUGIN_TIMER, &p);
3135 }
3136
3137 }
3138
3139 static void sigterm_handler(int sig)
3140 {
3141 LOG(1, 0, 0, 0, "Shutting down cleanly\n");
3142 if (config->save_state)
3143 dump_state();
3144
3145 main_quit++;
3146 }
3147
3148 static void sigquit_handler(int sig)
3149 {
3150 int i;
3151
3152 LOG(1, 0, 0, 0, "Shutting down without saving sessions\n");
3153 for (i = 1; i < MAXSESSION; i++)
3154 {
3155 if (session[i].opened)
3156 sessionkill(i, "L2TPNS Closing");
3157 }
3158 for (i = 1; i < MAXTUNNEL; i++)
3159 {
3160 if (tunnel[i].ip || tunnel[i].state)
3161 tunnelshutdown(i, "L2TPNS Closing");
3162 }
3163
3164 main_quit++;
3165 }
3166
3167 static void sigchild_handler(int sig)
3168 {
3169 while (waitpid(-1, NULL, WNOHANG) > 0)
3170 ;
3171 }
3172
3173 static void read_state()
3174 {
3175 struct stat sb;
3176 int i;
3177 ippoolt itmp;
3178 FILE *f;
3179 char magic[sizeof(DUMP_MAGIC) - 1];
3180 u32 buf[2];
3181
3182 if (!config->save_state)
3183 {
3184 unlink(STATEFILE);
3185 return ;
3186 }
3187
3188 if (stat(STATEFILE, &sb) < 0)
3189 {
3190 unlink(STATEFILE);
3191 return ;
3192 }
3193
3194 if (sb.st_mtime < (time(NULL) - 60))
3195 {
3196 LOG(0, 0, 0, 0, "State file is too old to read, ignoring\n");
3197 unlink(STATEFILE);
3198 return ;
3199 }
3200
3201 f = fopen(STATEFILE, "r");
3202 unlink(STATEFILE);
3203
3204 if (!f)
3205 {
3206 LOG(0, 0, 0, 0, "Can't read state file: %s\n", strerror(errno));
3207 exit(1);
3208 }
3209
3210 if (fread(magic, sizeof(magic), 1, f) != 1 || strncmp(magic, DUMP_MAGIC, sizeof(magic)))
3211 {
3212 LOG(0, 0, 0, 0, "Bad state file magic\n");
3213 exit(1);
3214 }
3215
3216 LOG(1, 0, 0, 0, "Reading state information\n");
3217 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] > MAXIPPOOL || buf[1] != sizeof(ippoolt))
3218 {
3219 LOG(0, 0, 0, 0, "Error/mismatch reading ip pool header from state file\n");
3220 exit(1);
3221 }
3222
3223 if (buf[0] > ip_pool_size)
3224 {
3225 LOG(0, 0, 0, 0, "ip pool has shrunk! state = %d, current = %d\n", buf[0], ip_pool_size);
3226 exit(1);
3227 }
3228
3229 LOG(2, 0, 0, 0, "Loading %u ip addresses\n", buf[0]);
3230 for (i = 0; i < buf[0]; i++)
3231 {
3232 if (fread(&itmp, sizeof(itmp), 1, f) != 1)
3233 {
3234 LOG(0, 0, 0, 0, "Error reading ip %d from state file: %s\n", i, strerror(errno));
3235 exit(1);
3236 }
3237
3238 if (itmp.address != ip_address_pool[i].address)
3239 {
3240 LOG(0, 0, 0, 0, "Mismatched ip %d from state file: pool may only be extended\n", i);
3241 exit(1);
3242 }
3243
3244 memcpy(&ip_address_pool[i], &itmp, sizeof(itmp));
3245 }
3246
3247 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXTUNNEL || buf[1] != sizeof(tunnelt))
3248 {
3249 LOG(0, 0, 0, 0, "Error/mismatch reading tunnel header from state file\n");
3250 exit(1);
3251 }
3252
3253 LOG(2, 0, 0, 0, "Loading %u tunnels\n", MAXTUNNEL);
3254 if (fread(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3255 {
3256 LOG(0, 0, 0, 0, "Error reading tunnel data from state file\n");
3257 exit(1);
3258 }
3259
3260 for (i = 0; i < MAXTUNNEL; i++)
3261 {
3262 tunnel[i].controlc = 0;
3263 tunnel[i].controls = NULL;
3264 tunnel[i].controle = NULL;
3265 if (*tunnel[i].hostname)
3266 LOG(3, 0, 0, 0, "Created tunnel for %s\n", tunnel[i].hostname);
3267 }
3268
3269 if (fread(buf, sizeof(buf), 1, f) != 1 || buf[0] != MAXSESSION || buf[1] != sizeof(sessiont))
3270 {
3271 LOG(0, 0, 0, 0, "Error/mismatch reading session header from state file\n");
3272 exit(1);
3273 }
3274
3275 LOG(2, 0, 0, 0, "Loading %u sessions\n", MAXSESSION);
3276 if (fread(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3277 {
3278 LOG(0, 0, 0, 0, "Error reading session data from state file\n");
3279 exit(1);
3280 }
3281
3282 for (i = 0; i < MAXSESSION; i++)
3283 {
3284 session[i].tbf_in = 0;
3285 session[i].tbf_out = 0;
3286 if (session[i].opened)
3287 {
3288 LOG(2, 0, i, 0, "Loaded active session for user %s\n", session[i].user);
3289 if (session[i].ip)
3290 sessionsetup(session[i].tunnel, i);
3291 }
3292 }
3293
3294 fclose(f);
3295 LOG(0, 0, 0, 0, "Loaded saved state information\n");
3296 }
3297
3298 static void dump_state()
3299 {
3300 FILE *f;
3301 u32 buf[2];
3302
3303 if (!config->save_state)
3304 return;
3305
3306 do
3307 {
3308 if (!(f = fopen(STATEFILE, "w")))
3309 break;
3310
3311 LOG(1, 0, 0, 0, "Dumping state information\n");
3312
3313 if (fwrite(DUMP_MAGIC, sizeof(DUMP_MAGIC) - 1, 1, f) != 1)
3314 break;
3315
3316 LOG(2, 0, 0, 0, "Dumping %u ip addresses\n", ip_pool_size);
3317 buf[0] = ip_pool_size;
3318 buf[1] = sizeof(ippoolt);
3319 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3320 break;
3321 if (fwrite(ip_address_pool, sizeof(ippoolt), ip_pool_size, f) != ip_pool_size)
3322 break;
3323
3324 LOG(2, 0, 0, 0, "Dumping %u tunnels\n", MAXTUNNEL);
3325 buf[0] = MAXTUNNEL;
3326 buf[1] = sizeof(tunnelt);
3327 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3328 break;
3329 if (fwrite(tunnel, sizeof(tunnelt), MAXTUNNEL, f) != MAXTUNNEL)
3330 break;
3331
3332 LOG(2, 0, 0, 0, "Dumping %u sessions\n", MAXSESSION);
3333 buf[0] = MAXSESSION;
3334 buf[1] = sizeof(sessiont);
3335 if (fwrite(buf, sizeof(buf), 1, f) != 1)
3336 break;
3337 if (fwrite(session, sizeof(sessiont), MAXSESSION, f) != MAXSESSION)
3338 break;
3339
3340 if (fclose(f) == 0)
3341 return ; // OK
3342 }
3343 while (0);
3344
3345 LOG(0, 0, 0, 0, "Can't write state information: %s\n", strerror(errno));
3346 unlink(STATEFILE);
3347 }
3348
3349 static void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response)
3350 {
3351 MD5_CTX ctx;
3352 *challenge_response = NULL;
3353
3354 if (!*config->l2tpsecret)
3355 {
3356 LOG(0, 0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3357 return;
3358 }
3359
3360 LOG(4, 0, 0, 0, " Building challenge response for CHAP request\n");
3361
3362 *challenge_response = (char *)calloc(17, 1);
3363
3364 MD5Init(&ctx);
3365 MD5Update(&ctx, &id, 1);
3366 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3367 MD5Update(&ctx, challenge, challenge_length);
3368 MD5Final(*challenge_response, &ctx);
3369
3370 return;
3371 }
3372
3373 static int facility_value(char *name)
3374 {
3375 int i;
3376 for (i = 0; facilitynames[i].c_name; i++)
3377 {
3378 if (strcmp(facilitynames[i].c_name, name) == 0)
3379 return facilitynames[i].c_val;
3380 }
3381 return 0;
3382 }
3383
3384 static void update_config()
3385 {
3386 int i;
3387 static int timeout = 0;
3388 static int interval = 0;
3389
3390 // Update logging
3391 closelog();
3392 syslog_log = 0;
3393 if (log_stream)
3394 {
3395 fclose(log_stream);
3396 log_stream = NULL;
3397 }
3398 if (*config->log_filename)
3399 {
3400 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3401 {
3402 char *p = config->log_filename + 7;
3403 if (*p)
3404 {
3405 openlog("l2tpns", LOG_PID, facility_value(p));
3406 syslog_log = 1;
3407 }
3408 }
3409 else if (strchr(config->log_filename, '/') == config->log_filename)
3410 {
3411 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3412 {
3413 fseek(log_stream, 0, SEEK_END);
3414 setbuf(log_stream, NULL);
3415 }
3416 else
3417 {
3418 log_stream = stderr;
3419 setbuf(log_stream, NULL);
3420 }
3421 }
3422 }
3423 else
3424 {
3425 log_stream = stderr;
3426 setbuf(log_stream, NULL);
3427 }
3428
3429
3430 // Update radius
3431 config->numradiusservers = 0;
3432 for (i = 0; i < MAXRADSERVER; i++)
3433 if (config->radiusserver[i])
3434 {
3435 config->numradiusservers++;
3436 // Set radius port: if not set, take the port from the
3437 // first radius server. For the first radius server,
3438 // take the #defined default value from l2tpns.h
3439
3440 // test twice, In case someone works with
3441 // a secondary radius server without defining
3442 // a primary one, this will work even then.
3443 if (i>0 && !config->radiusport[i])
3444 config->radiusport[i] = config->radiusport[i-1];
3445 if (!config->radiusport[i])
3446 config->radiusport[i] = RADPORT;
3447 }
3448
3449 if (!config->numradiusservers)
3450 {
3451 LOG(0, 0, 0, 0, "No RADIUS servers defined!\n");
3452 }
3453
3454 config->num_radfds = 2 << RADIUS_SHIFT;
3455
3456 // Update plugins
3457 for (i = 0; i < MAXPLUGINS; i++)
3458 {
3459 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3460 continue;
3461
3462 if (*config->plugins[i])
3463 {
3464 // Plugin added
3465 add_plugin(config->plugins[i]);
3466 }
3467 else if (*config->old_plugins[i])
3468 {
3469 // Plugin removed
3470 remove_plugin(config->old_plugins[i]);
3471 }
3472 }
3473 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3474 if (!config->cleanup_interval) config->cleanup_interval = 10;
3475 if (!config->multi_read_count) config->multi_read_count = 10;
3476 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3477 if (!*config->cluster_interface)
3478 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3479
3480 if (!config->cluster_hb_interval)
3481 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3482
3483 if (!config->cluster_hb_timeout)
3484 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3485
3486 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3487 {
3488 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3489 // late, ensure we're sufficiently larger than that
3490 int t = 4 * config->cluster_hb_interval + 11;
3491
3492 if (config->cluster_hb_timeout < t)
3493 {
3494 LOG(0,0,0,0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3495 config->cluster_hb_timeout = t;
3496 }
3497
3498 // Push timing changes to the slaves immediately if we're the master
3499 if (config->cluster_iam_master)
3500 cluster_heartbeat();
3501
3502 interval = config->cluster_hb_interval;
3503 timeout = config->cluster_hb_timeout;
3504 }
3505
3506 // Write PID file
3507 if (*config->pid_file == '/' && !config->wrote_pid)
3508 {
3509 FILE *f;
3510 if ((f = fopen(config->pid_file, "w")))
3511 {
3512 fprintf(f, "%d\n", getpid());
3513 fclose(f);
3514 config->wrote_pid = 1;
3515 }
3516 else
3517 {
3518 LOG(0, 0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3519 }
3520 }
3521
3522 config->reload_config = 0;
3523 }
3524
3525 static void read_config_file()
3526 {
3527 FILE *f;
3528
3529 if (!config->config_file) return;
3530 if (!(f = fopen(config->config_file, "r")))
3531 {
3532 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3533 return;
3534 }
3535
3536 LOG(3, 0, 0, 0, "Reading config file %s\n", config->config_file);
3537 cli_do_file(f);
3538 LOG(3, 0, 0, 0, "Done reading config file\n");
3539 fclose(f);
3540 update_config();
3541 }
3542
3543 int sessionsetup(tunnelidt t, sessionidt s)
3544 {
3545 // A session now exists, set it up
3546 ipt ip;
3547 char *user;
3548 sessionidt i;
3549 int r;
3550
3551 CSTAT(call_sessionsetup);
3552
3553 LOG(3, session[s].ip, s, t, "Doing session setup for session\n");
3554
3555 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
3556 {
3557 assign_ip_address(s);
3558 if (!session[s].ip)
3559 {
3560 LOG(0, 0, s, t, " No IP allocated. The IP address pool is FULL!\n");
3561 sessionshutdown(s, "No IP addresses available");
3562 return 0;
3563 }
3564 LOG(3, 0, s, t, " No IP allocated. Assigned %s from pool\n",
3565 inet_toa(htonl(session[s].ip)));
3566 }
3567
3568
3569 // Make sure this is right
3570 session[s].tunnel = t;
3571
3572 // zap old sessions with same IP and/or username
3573 // Don't kill gardened sessions - doing so leads to a DoS
3574 // from someone who doesn't need to know the password
3575 {
3576 ip = session[s].ip;
3577 user = session[s].user;
3578 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3579 {
3580 if (i == s) continue;
3581 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
3582 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
3583 sessionkill(i, "Duplicate session for users");
3584 }
3585 }
3586
3587 {
3588 int routed = 0;
3589
3590 // Add the route for this session.
3591 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
3592 {
3593 if ((session[s].ip & session[s].route[r].mask) ==
3594 (session[s].route[r].ip & session[s].route[r].mask))
3595 routed++;
3596
3597 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
3598 }
3599
3600 // Static IPs need to be routed if not already
3601 // convered by a Framed-Route. Anything else is part
3602 // of the IP address pool and is already routed, it
3603 // just needs to be added to the IP cache.
3604 if (session[s].ip_pool_index == -1) // static ip
3605 {
3606 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
3607 }
3608 else
3609 cache_ipmap(session[s].ip, s);
3610 }
3611
3612 if (!session[s].unique_id)
3613 {
3614 // did this session just finish radius?
3615 LOG(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
3616 sendipcp(t, s);
3617 session[s].unique_id = ++last_id;
3618 }
3619
3620 // Run the plugin's against this new session.
3621 {
3622 struct param_new_session data = { &tunnel[t], &session[s] };
3623 run_plugins(PLUGIN_NEW_SESSION, &data);
3624 }
3625
3626 // Allocate TBFs if throttled
3627 if (session[s].throttle_in || session[s].throttle_out)
3628 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
3629
3630 session[s].last_packet = time_now;
3631
3632 {
3633 char *sessionip, *tunnelip;
3634 sessionip = strdup(inet_toa(htonl(session[s].ip)));
3635 tunnelip = strdup(inet_toa(htonl(tunnel[t].ip)));
3636 LOG(2, session[s].ip, s, t, "Login by %s at %s from %s (%s)\n",
3637 session[s].user, sessionip, tunnelip, tunnel[t].hostname);
3638 if (sessionip) free(sessionip);
3639 if (tunnelip) free(tunnelip);
3640 }
3641
3642 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
3643
3644 return 1; // RADIUS OK and IP allocated, done...
3645 }
3646
3647 //
3648 // This session just got dropped on us by the master or something.
3649 // Make sure our tables up up to date...
3650 //
3651 int load_session(sessionidt s, sessiont *new)
3652 {
3653 int i;
3654 int newip = 0;
3655
3656 // Sanity checks.
3657 if (new->ip_pool_index >= MAXIPPOOL ||
3658 new->tunnel >= MAXTUNNEL)
3659 {
3660 LOG(0,0,s,0, "Strange session update received!\n");
3661 // FIXME! What to do here?
3662 return 0;
3663 }
3664
3665 //
3666 // Ok. All sanity checks passed. Now we're committed to
3667 // loading the new session.
3668 //
3669
3670 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
3671
3672 // See if routes/ip cache need updating
3673 if (new->ip != session[s].ip)
3674 newip++;
3675
3676 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
3677 if (new->route[i].ip != session[s].route[i].ip ||
3678 new->route[i].mask != session[s].route[i].mask)
3679 newip++;
3680
3681 // needs update
3682 if (newip)
3683 {
3684 int routed = 0;
3685
3686 // remove old routes...
3687 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
3688 {
3689 if ((session[s].ip & session[s].route[i].mask) ==
3690 (session[s].route[i].ip & session[s].route[i].mask))
3691 routed++;
3692
3693 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
3694 }
3695
3696 // ...ip
3697 if (session[s].ip)
3698 {
3699 if (session[s].ip_pool_index == -1) // static IP
3700 {
3701 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
3702 }
3703 else // It's part of the IP pool, remove it manually.
3704 uncache_ipmap(session[s].ip);
3705 }
3706
3707 routed = 0;
3708
3709 // add new routes...
3710 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
3711 {
3712 if ((new->ip & new->route[i].mask) ==
3713 (new->route[i].ip & new->route[i].mask))
3714 routed++;
3715
3716 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
3717 }
3718
3719 // ...ip
3720 if (new->ip)
3721 {
3722 // If there's a new one, add it.
3723 if (new->ip_pool_index == -1)
3724 {
3725 if (!routed) routeset(s, new->ip, 0, 0, 1);
3726 }
3727 else
3728 cache_ipmap(new->ip, s);
3729 }
3730 }
3731
3732 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
3733 // for walking the sessions to forward byte counts to the master.
3734 config->cluster_highest_sessionid = s;
3735
3736 // TEMP: old session struct used a u32 to define the throttle
3737 // speed for both up/down, new uses a u16 for each. Deal with
3738 // sessions from an old master for migration.
3739 if (new->throttle_out == 0 && new->tbf_out)
3740 new->throttle_out = new->throttle_in;
3741
3742 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
3743
3744 // Do fixups into address pool.
3745 if (new->ip_pool_index != -1)
3746 fix_address_pool(s);
3747
3748 return 1;
3749 }
3750
3751 static void initplugins()
3752 {
3753 int i;
3754
3755 loaded_plugins = ll_init();
3756 // Initialize the plugins to nothing
3757 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
3758 plugins[i] = ll_init();
3759 }
3760
3761 static void *open_plugin(char *plugin_name, int load)
3762 {
3763 char path[256] = "";
3764
3765 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
3766 LOG(2, 0, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
3767 return dlopen(path, RTLD_NOW);
3768 }
3769
3770 // plugin callback to get a config value
3771 static void *getconfig(char *key, enum config_typet type)
3772 {
3773 int i;
3774
3775 for (i = 0; config_values[i].key; i++)
3776 {
3777 if (!strcmp(config_values[i].key, key))
3778 {
3779 if (config_values[i].type == type)
3780 return ((void *) config) + config_values[i].offset;
3781
3782 LOG(1, 0, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
3783 key, type, config_values[i].type);
3784
3785 return 0;
3786 }
3787 }
3788
3789 LOG(1, 0, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
3790 return 0;
3791 }
3792
3793 static int add_plugin(char *plugin_name)
3794 {
3795 static struct pluginfuncs funcs = {
3796 _log,
3797 _log_hex,
3798 inet_toa,
3799 sessionbyuser,
3800 sessiontbysessionidt,
3801 sessionidtbysessiont,
3802 radiusnew,
3803 radiussend,
3804 getconfig,
3805 sessionkill,
3806 throttle_session,
3807 cluster_send_session,
3808 };
3809
3810 void *p = open_plugin(plugin_name, 1);
3811 int (*initfunc)(struct pluginfuncs *);
3812 int i;
3813
3814 if (!p)
3815 {
3816 LOG(1, 0, 0, 0, " Plugin load failed: %s\n", dlerror());
3817 return -1;
3818 }
3819
3820 if (ll_contains(loaded_plugins, p))
3821 {
3822 dlclose(p);
3823 return 0; // already loaded
3824 }
3825
3826 {
3827 int *v = dlsym(p, "plugin_api_version");
3828 if (!v || *v != PLUGIN_API_VERSION)
3829 {
3830 LOG(1, 0, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
3831 dlclose(p);
3832 return -1;
3833 }
3834 }
3835
3836 if ((initfunc = dlsym(p, "plugin_init")))
3837 {
3838 if (!initfunc(&funcs))
3839 {
3840 LOG(1, 0, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
3841 dlclose(p);
3842 return -1;
3843 }
3844 }
3845
3846 ll_push(loaded_plugins, p);
3847
3848 for (i = 0; i < max_plugin_functions; i++)
3849 {
3850 void *x;
3851 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3852 {
3853 LOG(3, 0, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
3854 ll_push(plugins[i], x);
3855 }
3856 }
3857
3858 LOG(2, 0, 0, 0, " Loaded plugin %s\n", plugin_name);
3859 return 1;
3860 }
3861
3862 static void run_plugin_done(void *plugin)
3863 {
3864 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
3865
3866 if (donefunc)
3867 donefunc();
3868 }
3869
3870 static int remove_plugin(char *plugin_name)
3871 {
3872 void *p = open_plugin(plugin_name, 0);
3873 int loaded = 0;
3874
3875 if (!p)
3876 return -1;
3877
3878 if (ll_contains(loaded_plugins, p))
3879 {
3880 int i;
3881 for (i = 0; i < max_plugin_functions; i++)
3882 {
3883 void *x;
3884 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
3885 ll_delete(plugins[i], x);
3886 }
3887
3888 ll_delete(loaded_plugins, p);
3889 run_plugin_done(p);
3890 loaded = 1;
3891 }
3892
3893 dlclose(p);
3894 LOG(2, 0, 0, 0, "Removed plugin %s\n", plugin_name);
3895 return loaded;
3896 }
3897
3898 int run_plugins(int plugin_type, void *data)
3899 {
3900 int (*func)(void *data);
3901
3902 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
3903 return PLUGIN_RET_ERROR;
3904
3905 ll_reset(plugins[plugin_type]);
3906 while ((func = ll_next(plugins[plugin_type])))
3907 {
3908 int r = func(data);
3909
3910 if (r != PLUGIN_RET_OK)
3911 return r; // stop here
3912 }
3913
3914 return PLUGIN_RET_OK;
3915 }
3916
3917 static void plugins_done()
3918 {
3919 void *p;
3920
3921 ll_reset(loaded_plugins);
3922 while ((p = ll_next(loaded_plugins)))
3923 run_plugin_done(p);
3924 }
3925
3926 static void processcontrol(u8 * buf, int len, struct sockaddr_in *addr, int alen)
3927 {
3928 struct nsctl request;
3929 struct nsctl response;
3930 int type = unpack_control(&request, buf, len);
3931 int r;
3932 void *p;
3933
3934 if (log_stream && config->debug >= 4)
3935 {
3936 if (type < 0)
3937 {
3938 LOG(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Bogus control message (%d)\n", type);
3939 }
3940 else
3941 {
3942 LOG(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Received ");
3943 dump_control(&request, log_stream);
3944 }
3945 }
3946
3947 switch (type)
3948 {
3949 case NSCTL_REQ_LOAD:
3950 if (request.argc != 1)
3951 {
3952 response.type = NSCTL_RES_ERR;
3953 response.argc = 1;
3954 response.argv[0] = "name of plugin required";
3955 }
3956 else if ((r = add_plugin(request.argv[0])) < 1)
3957 {
3958 response.type = NSCTL_RES_ERR;
3959 response.argc = 1;
3960 response.argv[0] = !r
3961 ? "plugin already loaded"
3962 : "error loading plugin";
3963 }
3964 else
3965 {
3966 response.type = NSCTL_RES_OK;
3967 response.argc = 0;
3968 }
3969
3970 break;
3971
3972 case NSCTL_REQ_UNLOAD:
3973 if (request.argc != 1)
3974 {
3975 response.type = NSCTL_RES_ERR;
3976 response.argc = 1;
3977 response.argv[0] = "name of plugin required";
3978 }
3979 else if ((r = remove_plugin(request.argv[0])) < 1)
3980 {
3981 response.type = NSCTL_RES_ERR;
3982 response.argc = 1;
3983 response.argv[0] = !r
3984 ? "plugin not loaded"
3985 : "plugin not found";
3986 }
3987 else
3988 {
3989 response.type = NSCTL_RES_OK;
3990 response.argc = 0;
3991 }
3992
3993 break;
3994
3995 case NSCTL_REQ_HELP:
3996 response.type = NSCTL_RES_OK;
3997 response.argc = 0;
3998
3999 ll_reset(loaded_plugins);
4000 while ((p = ll_next(loaded_plugins)))
4001 {
4002 char **help = dlsym(p, "plugin_control_help");
4003 while (response.argc < 0xff && help && *help)
4004 response.argv[response.argc++] = *help++;
4005 }
4006
4007 break;
4008
4009 case NSCTL_REQ_CONTROL:
4010 {
4011 struct param_control param = {
4012 config->cluster_iam_master,
4013 request.argc,
4014 request.argv,
4015 0,
4016 NULL,
4017 };
4018
4019 int r = run_plugins(PLUGIN_CONTROL, &param);
4020
4021 if (r == PLUGIN_RET_ERROR)
4022 {
4023 response.type = NSCTL_RES_ERR;
4024 response.argc = 1;
4025 response.argv[0] = param.additional
4026 ? param.additional
4027 : "error returned by plugin";
4028 }
4029 else if (r == PLUGIN_RET_NOTMASTER)
4030 {
4031 static char msg[] = "must be run on master: 000.000.000.000";
4032
4033 response.type = NSCTL_RES_ERR;
4034 response.argc = 1;
4035 if (config->cluster_master_address)
4036 {
4037 strcpy(msg + 23, inet_toa(config->cluster_master_address));
4038 response.argv[0] = msg;
4039 }
4040 else
4041 {
4042 response.argv[0] = "must be run on master: none elected";
4043 }
4044 }
4045 else if (!(param.response & NSCTL_RESPONSE))
4046 {
4047 response.type = NSCTL_RES_ERR;
4048 response.argc = 1;
4049 response.argv[0] = param.response
4050 ? "unrecognised response value from plugin"
4051 : "unhandled action";
4052 }
4053 else
4054 {
4055 response.type = param.response;
4056 response.argc = 0;
4057 if (param.additional)
4058 {
4059 response.argc = 1;
4060 response.argv[0] = param.additional;
4061 }
4062 }
4063 }
4064
4065 break;
4066
4067 default:
4068 response.type = NSCTL_RES_ERR;
4069 response.argc = 1;
4070 response.argv[0] = "error unpacking control packet";
4071 }
4072
4073 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4074 if (!buf)
4075 {
4076 LOG(2, ntohl(addr->sin_addr.s_addr), 0, 0, "Failed to allocate nsctl response\n");
4077 return;
4078 }
4079
4080 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4081 if (r > 0)
4082 {
4083 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4084 if (log_stream && config->debug >= 4)
4085 {
4086 LOG(4, ntohl(addr->sin_addr.s_addr), 0, 0, "Sent ");
4087 dump_control(&response, log_stream);
4088 }
4089 }
4090 else
4091 LOG(2, ntohl(addr->sin_addr.s_addr), 0, 0, "Failed to pack nsctl response (%d)\n", r);
4092
4093 free(buf);
4094 }
4095
4096 static tunnelidt new_tunnel()
4097 {
4098 tunnelidt i;
4099 for (i = 1; i < MAXTUNNEL; i++)
4100 {
4101 if (tunnel[i].state == TUNNELFREE)
4102 {
4103 LOG(4, 0, 0, i, "Assigning tunnel ID %d\n", i);
4104 if (i > config->cluster_highest_tunnelid)
4105 config->cluster_highest_tunnelid = i;
4106 return i;
4107 }
4108 }
4109 LOG(0, 0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4110 return 0;
4111 }
4112
4113 //
4114 // We're becoming the master. Do any required setup..
4115 //
4116 // This is principally telling all the plugins that we're
4117 // now a master, and telling them about all the sessions
4118 // that are active too..
4119 //
4120 void become_master(void)
4121 {
4122 int s, i;
4123 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4124
4125 // running a bunch of iptables commands is slow and can cause
4126 // the master to drop tunnels on takeover--kludge around the
4127 // problem by forking for the moment (note: race)
4128 if (!fork_and_close())
4129 {
4130 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4131 {
4132 if (!session[s].tunnel) // Not an in-use session.
4133 continue;
4134
4135 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4136 }
4137 exit(0);
4138 }
4139
4140 // add radius fds
4141 for (i = 0; i < config->num_radfds; i++)
4142 {
4143 FD_SET(radfds[i], &readset);
4144 if (radfds[i] > readset_n)
4145 readset_n = radfds[i];
4146 }
4147 }
4148
4149 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4150 {
4151 int s, i;
4152 int count = 0;
4153 int buckets[64];
4154
4155 if (CLI_HELP_REQUESTED)
4156 return CLI_HELP_NO_ARGS;
4157
4158 time(&time_now);
4159 for (i = 0; i < 64;++i) buckets[i] = 0;
4160
4161 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4162 {
4163 int idle;
4164 if (!session[s].tunnel)
4165 continue;
4166
4167 idle = time_now - session[s].last_packet;
4168 idle /= 5 ; // In multiples of 5 seconds.
4169 if (idle < 0)
4170 idle = 0;
4171 if (idle > 63)
4172 idle = 63;
4173
4174 ++count;
4175 ++buckets[idle];
4176 }
4177
4178 for (i = 0; i < 63; ++i)
4179 {
4180 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4181 }
4182 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4183 cli_print(cli, "%d total sessions open.", count);
4184 return CLI_OK;
4185 }
4186
4187 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4188 {
4189 int s, i;
4190 int count = 0;
4191 int buckets[64];
4192
4193 if (CLI_HELP_REQUESTED)
4194 return CLI_HELP_NO_ARGS;
4195
4196 time(&time_now);
4197 for (i = 0; i < 64;++i) buckets[i] = 0;
4198
4199 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4200 {
4201 int open = 0, d;
4202 if (!session[s].tunnel)
4203 continue;
4204
4205 d = time_now - session[s].opened;
4206 if (d < 0)
4207 d = 0;
4208 while (d > 1 && open < 32)
4209 {
4210 ++open;
4211 d >>= 1; // half.
4212 }
4213 ++count;
4214 ++buckets[open];
4215 }
4216
4217 s = 1;
4218 for (i = 0; i < 30; ++i)
4219 {
4220 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4221 s <<= 1;
4222 }
4223 cli_print(cli, "%d total sessions open.", count);
4224 return CLI_OK;
4225 }
4226
4227 /* Unhide an avp.
4228 *
4229 * This unencodes the AVP using the L2TP CHAP secret and the
4230 * previously stored random vector. It replaces the hidden data with
4231 * the cleartext data and returns the length of the cleartext data
4232 * (including the AVP "header" of 6 bytes).
4233 *
4234 * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
4235 */
4236 static int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length)
4237 {
4238 MD5_CTX ctx;
4239 u8 *cursor;
4240 u8 digest[16];
4241 u8 working_vector[16];
4242 uint16_t hidden_length;
4243 u8 type[2];
4244 size_t done, todo;
4245 u8 *output;
4246
4247 // Find the AVP type.
4248 type[0] = *(avp + 4);
4249 type[1] = *(avp + 5);
4250
4251 // Line up with the hidden data
4252 cursor = output = avp + 6;
4253
4254 // Compute initial pad
4255 MD5Init(&ctx);
4256 MD5Update(&ctx, type, 2);
4257 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4258 MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
4259 MD5Final(digest, &ctx);
4260
4261 // Get hidden length
4262 hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
4263
4264 // Keep these for later use
4265 working_vector[0] = *cursor;
4266 working_vector[1] = *(cursor + 1);
4267 cursor += 2;
4268
4269 if (hidden_length > length - 8)
4270 {
4271 LOG(1, 0, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
4272 return 0;
4273 }
4274
4275 /* Decrypt remainder */
4276 done = 2;
4277 todo = hidden_length;
4278 while (todo)
4279 {
4280 working_vector[done] = *cursor;
4281 *output = digest[done] ^ *cursor;
4282 ++output;
4283 ++cursor;
4284 --todo;
4285 ++done;
4286 if (done == 16 && todo)
4287 {
4288 // Compute new digest
4289 done = 0;
4290 MD5Init(&ctx);
4291 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4292 MD5Update(&ctx, &working_vector, 16);
4293 MD5Final(digest, &ctx);
4294 }
4295 }
4296
4297 return hidden_length + 6;
4298 }
4299