add session/idle timeouts
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005, 2006 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 1.167 2006-06-11 12:46:18 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 // calculated from config->l2tp_mtu
79 uint16_t MRU = 0; // PPP MRU
80 uint16_t MSS = 0; // TCP MSS
81
82 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
83 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
84
85 static void *ip_hash[256]; // Mapping from IP address to session structures.
86 struct ipv6radix {
87 int sess;
88 struct ipv6radix *branch;
89 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
90
91 // Traffic counters.
92 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
93 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
94 uint32_t eth_tx = 0;
95
96 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
97 time_t time_now = 0; // Current time in seconds since epoch.
98 static char time_now_string[64] = {0}; // Current time as a string.
99 static int time_changed = 0; // time_now changed
100 char main_quit = 0; // True if we're in the process of exiting.
101 static char main_reload = 0; // Re-load pending
102 linked_list *loaded_plugins;
103 linked_list *plugins[MAX_PLUGIN_TYPES];
104
105 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
106 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
107
108 config_descriptt config_values[] = {
109 CONFIG("debug", debug, INT),
110 CONFIG("log_file", log_filename, STRING),
111 CONFIG("pid_file", pid_file, STRING),
112 CONFIG("random_device", random_device, STRING),
113 CONFIG("l2tp_secret", l2tp_secret, STRING),
114 CONFIG("l2tp_mtu", l2tp_mtu, INT),
115 CONFIG("ppp_restart_time", ppp_restart_time, INT),
116 CONFIG("ppp_max_configure", ppp_max_configure, INT),
117 CONFIG("ppp_max_failure", ppp_max_failure, INT),
118 CONFIG("primary_dns", default_dns1, IPv4),
119 CONFIG("secondary_dns", default_dns2, IPv4),
120 CONFIG("primary_radius", radiusserver[0], IPv4),
121 CONFIG("secondary_radius", radiusserver[1], IPv4),
122 CONFIG("primary_radius_port", radiusport[0], SHORT),
123 CONFIG("secondary_radius_port", radiusport[1], SHORT),
124 CONFIG("radius_accounting", radius_accounting, BOOL),
125 CONFIG("radius_interim", radius_interim, INT),
126 CONFIG("radius_secret", radiussecret, STRING),
127 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
128 CONFIG("radius_dae_port", radius_dae_port, SHORT),
129 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
130 CONFIG("guest_account", guest_user, STRING),
131 CONFIG("bind_address", bind_address, IPv4),
132 CONFIG("peer_address", peer_address, IPv4),
133 CONFIG("send_garp", send_garp, BOOL),
134 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
135 CONFIG("throttle_buckets", num_tbfs, INT),
136 CONFIG("accounting_dir", accounting_dir, STRING),
137 CONFIG("dump_speed", dump_speed, BOOL),
138 CONFIG("multi_read_count", multi_read_count, INT),
139 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
140 CONFIG("lock_pages", lock_pages, BOOL),
141 CONFIG("icmp_rate", icmp_rate, INT),
142 CONFIG("packet_limit", max_packets, INT),
143 CONFIG("cluster_address", cluster_address, IPv4),
144 CONFIG("cluster_interface", cluster_interface, STRING),
145 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
146 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
147 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
148 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
149 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
150 { NULL, 0, 0, 0 },
151 };
152
153 static char *plugin_functions[] = {
154 NULL,
155 "plugin_pre_auth",
156 "plugin_post_auth",
157 "plugin_packet_rx",
158 "plugin_packet_tx",
159 "plugin_timer",
160 "plugin_new_session",
161 "plugin_kill_session",
162 "plugin_control",
163 "plugin_radius_response",
164 "plugin_radius_reset",
165 "plugin_radius_account",
166 "plugin_become_master",
167 "plugin_new_session_master",
168 };
169
170 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
171
172 // Counters for shutdown sessions
173 static sessiont shut_acct[8192];
174 static sessionidt shut_acct_n = 0;
175
176 tunnelt *tunnel = NULL; // Array of tunnel structures.
177 bundlet *bundle = NULL; // Array of bundle structures.
178 fragmentationt *frag = NULL; // Array of fragmentation structures.
179 sessiont *session = NULL; // Array of session structures.
180 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
181 radiust *radius = NULL; // Array of radius structures.
182 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
183 ip_filtert *ip_filters = NULL; // Array of named filters.
184 static controlt *controlfree = 0;
185 struct Tstats *_statistics = NULL;
186 #ifdef RINGBUFFER
187 struct Tringbuffer *ringbuffer = NULL;
188 #endif
189
190 static void cache_ipmap(in_addr_t ip, int s);
191 static void uncache_ipmap(in_addr_t ip);
192 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
193 static void free_ip_address(sessionidt s);
194 static void dump_acct_info(int all);
195 static void sighup_handler(int sig);
196 static void shutdown_handler(int sig);
197 static void sigchild_handler(int sig);
198 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
199 static void update_config(void);
200 static void read_config_file(void);
201 static void initplugins(void);
202 static int add_plugin(char *plugin_name);
203 static int remove_plugin(char *plugin_name);
204 static void plugins_done(void);
205 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
206 static tunnelidt new_tunnel(void);
207 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
208 static void bundleclear(bundleidt b);
209
210 // on slaves, alow BGP to withdraw cleanly before exiting
211 #define QUIT_DELAY 5
212
213 // quit actions (master)
214 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
215 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
216
217 // return internal time (10ths since process startup), set f if given
218 // as a side-effect sets time_now, and time_changed
219 static clockt now(double *f)
220 {
221 struct timeval t;
222 gettimeofday(&t, 0);
223 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
224 if (t.tv_sec != time_now)
225 {
226 time_now = t.tv_sec;
227 time_changed++;
228 }
229 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
230 }
231
232 // work out a retry time based on try number
233 // This is a straight bounded exponential backoff.
234 // Maximum re-try time is 32 seconds. (2^5).
235 clockt backoff(uint8_t try)
236 {
237 if (try > 5) try = 5; // max backoff
238 return now(NULL) + 10 * (1 << try);
239 }
240
241
242 //
243 // Log a debug message. Typically called via the LOG macro
244 //
245 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
246 {
247 static char message[65536] = {0};
248 va_list ap;
249
250 #ifdef RINGBUFFER
251 if (ringbuffer)
252 {
253 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
254 ringbuffer->tail = 0;
255 if (ringbuffer->tail == ringbuffer->head)
256 if (++ringbuffer->head >= RINGBUFFER_SIZE)
257 ringbuffer->head = 0;
258
259 ringbuffer->buffer[ringbuffer->tail].level = level;
260 ringbuffer->buffer[ringbuffer->tail].session = s;
261 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
262 va_start(ap, format);
263 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
264 va_end(ap);
265 }
266 #endif
267
268 if (config->debug < level) return;
269
270 va_start(ap, format);
271 vsnprintf(message, sizeof(message), format, ap);
272
273 if (log_stream)
274 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
275 else if (syslog_log)
276 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
277
278 va_end(ap);
279 }
280
281 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
282 {
283 int i, j;
284 const uint8_t *d = data;
285
286 if (config->debug < level) return;
287
288 // No support for _log_hex to syslog
289 if (log_stream)
290 {
291 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
292 setvbuf(log_stream, NULL, _IOFBF, 16384);
293
294 for (i = 0; i < maxsize; )
295 {
296 fprintf(log_stream, "%4X: ", i);
297 for (j = i; j < maxsize && j < (i + 16); j++)
298 {
299 fprintf(log_stream, "%02X ", d[j]);
300 if (j == i + 7)
301 fputs(": ", log_stream);
302 }
303
304 for (; j < i + 16; j++)
305 {
306 fputs(" ", log_stream);
307 if (j == i + 7)
308 fputs(": ", log_stream);
309 }
310
311 fputs(" ", log_stream);
312 for (j = i; j < maxsize && j < (i + 16); j++)
313 {
314 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
315 fputc(d[j], log_stream);
316 else
317 fputc('.', log_stream);
318
319 if (j == i + 7)
320 fputs(" ", log_stream);
321 }
322
323 i = j;
324 fputs("\n", log_stream);
325 }
326
327 fflush(log_stream);
328 setbuf(log_stream, NULL);
329 }
330 }
331
332 // update a counter, accumulating 2^32 wraps
333 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
334 {
335 uint32_t new = *counter + delta;
336 if (new < *counter)
337 (*wrap)++;
338
339 *counter = new;
340 }
341
342 // initialise the random generator
343 static void initrandom(char *source)
344 {
345 static char path[sizeof(config->random_device)] = "*undefined*";
346
347 // reinitialise only if we are forced to do so or if the config has changed
348 if (source && !strncmp(path, source, sizeof(path)))
349 return;
350
351 // close previous source, if any
352 if (rand_fd >= 0)
353 close(rand_fd);
354
355 rand_fd = -1;
356
357 if (source)
358 {
359 // register changes
360 snprintf(path, sizeof(path), "%s", source);
361
362 if (*path == '/')
363 {
364 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
365 if (rand_fd < 0)
366 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
367 path, strerror(errno));
368 }
369 }
370 }
371
372 // fill buffer with random data
373 void random_data(uint8_t *buf, int len)
374 {
375 int n = 0;
376
377 CSTAT(random_data);
378 if (rand_fd >= 0)
379 {
380 n = read(rand_fd, buf, len);
381 if (n >= len) return;
382 if (n < 0)
383 {
384 if (errno != EAGAIN)
385 {
386 LOG(0, 0, 0, "Error reading from random source: %s\n",
387 strerror(errno));
388
389 // fall back to rand()
390 initrandom(NULL);
391 }
392
393 n = 0;
394 }
395 }
396
397 // append missing data
398 while (n < len)
399 // not using the low order bits from the prng stream
400 buf[n++] = (rand() >> 4) & 0xff;
401 }
402
403 // Add a route
404 //
405 // This adds it to the routing table, advertises it
406 // via BGP if enabled, and stuffs it into the
407 // 'sessionbyip' cache.
408 //
409 // 'ip' and 'mask' must be in _host_ order.
410 //
411 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
412 {
413 struct rtentry r;
414 int i;
415
416 if (!mask) mask = 0xffffffff;
417
418 ip &= mask; // Force the ip to be the first one in the route.
419
420 memset(&r, 0, sizeof(r));
421 r.rt_dev = config->tundevice;
422 r.rt_dst.sa_family = AF_INET;
423 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
424 r.rt_gateway.sa_family = AF_INET;
425 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
426 r.rt_genmask.sa_family = AF_INET;
427 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
428 r.rt_flags = (RTF_UP | RTF_STATIC);
429 if (gw)
430 r.rt_flags |= RTF_GATEWAY;
431 else if (mask == 0xffffffff)
432 r.rt_flags |= RTF_HOST;
433
434 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
435 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
436 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
437
438 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
439 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
440
441 #ifdef BGP
442 if (add)
443 bgp_add_route(htonl(ip), htonl(mask));
444 else
445 bgp_del_route(htonl(ip), htonl(mask));
446 #endif /* BGP */
447
448 // Add/Remove the IPs to the 'sessionbyip' cache.
449 // Note that we add the zero address in the case of
450 // a network route. Roll on CIDR.
451
452 // Note that 's == 0' implies this is the address pool.
453 // We still cache it here, because it will pre-fill
454 // the malloc'ed tree.
455
456 if (s)
457 {
458 if (!add) // Are we deleting a route?
459 s = 0; // Caching the session as '0' is the same as uncaching.
460
461 for (i = ip; (i&mask) == (ip&mask) ; ++i)
462 cache_ipmap(i, s);
463 }
464 }
465
466 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
467 {
468 struct in6_rtmsg rt;
469 char ipv6addr[INET6_ADDRSTRLEN];
470
471 if (ifr6fd < 0)
472 {
473 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
474 return;
475 }
476
477 memset(&rt, 0, sizeof(rt));
478
479 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
480 rt.rtmsg_dst_len = prefixlen;
481 rt.rtmsg_metric = 1;
482 rt.rtmsg_flags = RTF_UP;
483 rt.rtmsg_ifindex = tunidx;
484
485 LOG(1, 0, 0, "Route %s %s/%d\n",
486 add ? "add" : "del",
487 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
488 prefixlen);
489
490 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
491 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
492 strerror(errno));
493
494 // FIXME: need to add BGP routing (RFC2858)
495
496 if (s)
497 {
498 if (!add) // Are we deleting a route?
499 s = 0; // Caching the session as '0' is the same as uncaching.
500
501 cache_ipv6map(ip, prefixlen, s);
502 }
503
504 return;
505 }
506
507 // defined in linux/ipv6.h, but tricky to include from user-space
508 // TODO: move routing to use netlink rather than ioctl
509 struct in6_ifreq {
510 struct in6_addr ifr6_addr;
511 __u32 ifr6_prefixlen;
512 unsigned int ifr6_ifindex;
513 };
514
515 //
516 // Set up TUN interface
517 static void inittun(void)
518 {
519 struct ifreq ifr;
520 struct in6_ifreq ifr6;
521 struct sockaddr_in sin = {0};
522 memset(&ifr, 0, sizeof(ifr));
523 ifr.ifr_flags = IFF_TUN;
524
525 tunfd = open(TUNDEVICE, O_RDWR);
526 if (tunfd < 0)
527 { // fatal
528 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
529 exit(1);
530 }
531 {
532 int flags = fcntl(tunfd, F_GETFL, 0);
533 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
534 }
535 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
536 {
537 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
538 exit(1);
539 }
540 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
541 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
542 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
543
544 sin.sin_family = AF_INET;
545 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
546 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
547
548 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
549 {
550 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
551 exit(1);
552 }
553 /* Bump up the qlen to deal with bursts from the network */
554 ifr.ifr_qlen = 1000;
555 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
556 {
557 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
558 exit(1);
559 }
560 /* set MTU to modem MRU */
561 ifr.ifr_mtu = MRU;
562 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
563 {
564 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
565 exit(1);
566 }
567 ifr.ifr_flags = IFF_UP;
568 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
569 {
570 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
571 exit(1);
572 }
573 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
574 {
575 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
576 exit(1);
577 }
578 tunidx = ifr.ifr_ifindex;
579
580 // Only setup IPv6 on the tun device if we have a configured prefix
581 if (config->ipv6_prefix.s6_addr[0]) {
582 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
583
584 // Link local address is FE80::1
585 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
586 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
587 ifr6.ifr6_addr.s6_addr[1] = 0x80;
588 ifr6.ifr6_addr.s6_addr[15] = 1;
589 ifr6.ifr6_prefixlen = 64;
590 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
591 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
592 {
593 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
594 " %s\n", strerror(errno));
595 }
596
597 // Global address is prefix::1
598 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
599 ifr6.ifr6_addr = config->ipv6_prefix;
600 ifr6.ifr6_addr.s6_addr[15] = 1;
601 ifr6.ifr6_prefixlen = 64;
602 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
603 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
604 {
605 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
606 strerror(errno));
607 }
608 }
609 }
610
611 // set up UDP ports
612 static void initudp(void)
613 {
614 int on = 1;
615 struct sockaddr_in addr;
616
617 // Tunnel
618 memset(&addr, 0, sizeof(addr));
619 addr.sin_family = AF_INET;
620 addr.sin_port = htons(L2TPPORT);
621 addr.sin_addr.s_addr = config->bind_address;
622 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
623 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
624 {
625 int flags = fcntl(udpfd, F_GETFL, 0);
626 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
627 }
628 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Control
635 memset(&addr, 0, sizeof(addr));
636 addr.sin_family = AF_INET;
637 addr.sin_port = htons(NSCTL_PORT);
638 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
639 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
640 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
641 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
642 {
643 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
644 exit(1);
645 }
646
647 // Dynamic Authorization Extensions to RADIUS
648 memset(&addr, 0, sizeof(addr));
649 addr.sin_family = AF_INET;
650 addr.sin_port = htons(config->radius_dae_port);
651 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
652 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
653 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
654 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
655 {
656 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
657 exit(1);
658 }
659
660 // Intercept
661 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
662 }
663
664 //
665 // Find session by IP, < 1 for not found
666 //
667 // Confusingly enough, this 'ip' must be
668 // in _network_ order. This being the common
669 // case when looking it up from IP packet headers.
670 //
671 // We actually use this cache for two things.
672 // #1. For used IP addresses, this maps to the
673 // session ID that it's used by.
674 // #2. For un-used IP addresses, this maps to the
675 // index into the pool table that contains that
676 // IP address.
677 //
678
679 static int lookup_ipmap(in_addr_t ip)
680 {
681 uint8_t *a = (uint8_t *) &ip;
682 uint8_t **d = (uint8_t **) ip_hash;
683
684 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
685 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
686 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
687
688 return (int) (intptr_t) d[(size_t) *a];
689 }
690
691 static int lookup_ipv6map(struct in6_addr ip)
692 {
693 struct ipv6radix *curnode;
694 int i;
695 int s;
696 char ipv6addr[INET6_ADDRSTRLEN];
697
698 curnode = &ipv6_hash[ip.s6_addr[0]];
699 i = 1;
700 s = curnode->sess;
701
702 while (s == 0 && i < 15 && curnode->branch != NULL)
703 {
704 curnode = &curnode->branch[ip.s6_addr[i]];
705 s = curnode->sess;
706 i++;
707 }
708
709 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
710 inet_ntop(AF_INET6, &ip, ipv6addr,
711 INET6_ADDRSTRLEN),
712 s);
713
714 return s;
715 }
716
717 sessionidt sessionbyip(in_addr_t ip)
718 {
719 int s = lookup_ipmap(ip);
720 CSTAT(sessionbyip);
721
722 if (s > 0 && s < MAXSESSION && session[s].opened)
723 return (sessionidt) s;
724
725 return 0;
726 }
727
728 sessionidt sessionbyipv6(struct in6_addr ip)
729 {
730 int s;
731 CSTAT(sessionbyipv6);
732
733 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
734 (ip.s6_addr[0] == 0xFE &&
735 ip.s6_addr[1] == 0x80 &&
736 ip.s6_addr16[1] == 0 &&
737 ip.s6_addr16[2] == 0 &&
738 ip.s6_addr16[3] == 0)) {
739 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
740 } else {
741 s = lookup_ipv6map(ip);
742 }
743
744 if (s > 0 && s < MAXSESSION && session[s].opened)
745 return s;
746
747 return 0;
748 }
749
750 //
751 // Take an IP address in HOST byte order and
752 // add it to the sessionid by IP cache.
753 //
754 // (It's actually cached in network order)
755 //
756 static void cache_ipmap(in_addr_t ip, int s)
757 {
758 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
759 uint8_t *a = (uint8_t *) &nip;
760 uint8_t **d = (uint8_t **) ip_hash;
761 int i;
762
763 for (i = 0; i < 3; i++)
764 {
765 if (!d[(size_t) a[i]])
766 {
767 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
768 return;
769 }
770
771 d = (uint8_t **) d[(size_t) a[i]];
772 }
773
774 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
775
776 if (s > 0)
777 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
778
779 else if (s == 0)
780 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
781 // else a map to an ip pool index.
782 }
783
784 static void uncache_ipmap(in_addr_t ip)
785 {
786 cache_ipmap(ip, 0); // Assign it to the NULL session.
787 }
788
789 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
790 {
791 int i;
792 int bytes;
793 struct ipv6radix *curnode;
794 char ipv6addr[INET6_ADDRSTRLEN];
795
796 curnode = &ipv6_hash[ip.s6_addr[0]];
797
798 bytes = prefixlen >> 3;
799 i = 1;
800 while (i < bytes) {
801 if (curnode->branch == NULL)
802 {
803 if (!(curnode->branch = calloc(256,
804 sizeof (struct ipv6radix))))
805 return;
806 }
807 curnode = &curnode->branch[ip.s6_addr[i]];
808 i++;
809 }
810
811 curnode->sess = s;
812
813 if (s > 0)
814 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
815 inet_ntop(AF_INET6, &ip, ipv6addr,
816 INET6_ADDRSTRLEN),
817 prefixlen);
818 else if (s == 0)
819 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
820 inet_ntop(AF_INET6, &ip, ipv6addr,
821 INET6_ADDRSTRLEN),
822 prefixlen);
823 }
824
825 //
826 // CLI list to dump current ipcache.
827 //
828 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
829 {
830 char **d = (char **) ip_hash, **e, **f, **g;
831 int i, j, k, l;
832 int count = 0;
833
834 if (CLI_HELP_REQUESTED)
835 return CLI_HELP_NO_ARGS;
836
837 cli_print(cli, "%7s %s", "Sess#", "IP Address");
838
839 for (i = 0; i < 256; ++i)
840 {
841 if (!d[i])
842 continue;
843 e = (char **) d[i];
844 for (j = 0; j < 256; ++j)
845 {
846 if (!e[j])
847 continue;
848 f = (char **) e[j];
849 for (k = 0; k < 256; ++k)
850 {
851 if (!f[k])
852 continue;
853 g = (char **)f[k];
854 for (l = 0; l < 256; ++l)
855 {
856 if (!g[l])
857 continue;
858 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
859 ++count;
860 }
861 }
862 }
863 }
864 cli_print(cli, "%d entries in cache", count);
865 return CLI_OK;
866 }
867
868
869 // Find session by username, 0 for not found
870 // walled garden users aren't authenticated, so the username is
871 // reasonably useless. Ignore them to avoid incorrect actions
872 //
873 // This is VERY inefficent. Don't call it often. :)
874 //
875 sessionidt sessionbyuser(char *username)
876 {
877 int s;
878 CSTAT(sessionbyuser);
879
880 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
881 {
882 if (!session[s].opened)
883 continue;
884
885 if (session[s].walled_garden)
886 continue; // Skip walled garden users.
887
888 if (!strncmp(session[s].user, username, 128))
889 return s;
890
891 }
892 return 0; // Not found.
893 }
894
895 void send_garp(in_addr_t ip)
896 {
897 int s;
898 struct ifreq ifr;
899 uint8_t mac[6];
900
901 s = socket(PF_INET, SOCK_DGRAM, 0);
902 if (s < 0)
903 {
904 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
905 return;
906 }
907 memset(&ifr, 0, sizeof(ifr));
908 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
909 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
910 {
911 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
912 close(s);
913 return;
914 }
915 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
916 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
917 {
918 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
919 close(s);
920 return;
921 }
922 close(s);
923 sendarp(ifr.ifr_ifindex, mac, ip);
924 }
925
926 static sessiont *sessiontbysessionidt(sessionidt s)
927 {
928 if (!s || s >= MAXSESSION) return NULL;
929 return &session[s];
930 }
931
932 static sessionidt sessionidtbysessiont(sessiont *s)
933 {
934 sessionidt val = s-session;
935 if (s < session || val >= MAXSESSION) return 0;
936 return val;
937 }
938
939 // actually send a control message for a specific tunnel
940 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
941 {
942 struct sockaddr_in addr;
943
944 CSTAT(tunnelsend);
945
946 if (!t)
947 {
948 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
949 STAT(tunnel_tx_errors);
950 return;
951 }
952
953 if (!tunnel[t].ip)
954 {
955 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
956 STAT(tunnel_tx_errors);
957 return;
958 }
959
960 memset(&addr, 0, sizeof(addr));
961 addr.sin_family = AF_INET;
962 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
963 addr.sin_port = htons(tunnel[t].port);
964
965 // sequence expected, if sequence in message
966 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
967
968 // If this is a control message, deal with retries
969 if (*buf & 0x80)
970 {
971 tunnel[t].last = time_now; // control message sent
972 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
973 if (tunnel[t].try)
974 {
975 STAT(tunnel_retries);
976 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
977 }
978 }
979
980 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
981 {
982 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
983 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
984 STAT(tunnel_tx_errors);
985 return;
986 }
987
988 LOG_HEX(5, "Send Tunnel Data", buf, l);
989 STAT(tunnel_tx_packets);
990 INC_STAT(tunnel_tx_bytes, l);
991 }
992
993 //
994 // Tiny helper function to write data to
995 // the 'tun' device.
996 //
997 int tun_write(uint8_t * data, int size)
998 {
999 return write(tunfd, data, size);
1000 }
1001
1002 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1003 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1004 {
1005 int d = (tcp[12] >> 4) * 4;
1006 uint8_t *mss = 0;
1007 uint8_t *opts;
1008 uint8_t *data;
1009 uint16_t orig;
1010 uint32_t sum;
1011
1012 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1013 return;
1014
1015 if (tcp + d > buf + len) // short?
1016 return;
1017
1018 opts = tcp + 20;
1019 data = tcp + d;
1020
1021 while (opts < data)
1022 {
1023 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1024 {
1025 mss = opts + 2;
1026 if (mss + 2 > data) return; // short?
1027 break;
1028 }
1029
1030 if (*opts == 0) return; // end of options
1031 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1032 opts++;
1033 else
1034 opts += opts[1]; // skip over option
1035 }
1036
1037 if (!mss) return; // not found
1038 orig = ntohs(*(uint16_t *) mss);
1039
1040 if (orig <= MSS) return; // mss OK
1041
1042 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1043 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1044 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1045 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1046
1047 // set mss
1048 *(int16_t *) mss = htons(MSS);
1049
1050 // adjust checksum (see rfc1141)
1051 sum = orig + (~MSS & 0xffff);
1052 sum += ntohs(*(uint16_t *) (tcp + 16));
1053 sum = (sum & 0xffff) + (sum >> 16);
1054 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1055 }
1056
1057 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
1058 {
1059 uint16_t proto;
1060 if (extra) {
1061 // Skip the four extra bytes
1062 p += 4;
1063 l -= 4;
1064 }
1065
1066 // Process this frame
1067 if (*p & 1)
1068 {
1069 proto = *p++;
1070 l--;
1071 }
1072 else
1073 {
1074 proto = ntohs(*(uint16_t *) p);
1075 p += 2;
1076 l -= 2;
1077 }
1078
1079 if (proto == PPPIP)
1080 {
1081 if (session[s].die)
1082 {
1083 LOG(4, s, t, "MPPP: Session %u is closing. Don't process PPP packets\n", s);
1084 return; // closing session, PPP not processed
1085 }
1086
1087 session[s].last_packet = session[s].last_data = time_now;
1088 processipin(s, t, p, l);
1089 }
1090 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
1091 {
1092 if (session[s].die)
1093 {
1094 LOG(4, s, t, "MPPP: Session %u is closing. Don't process PPP packets\n", s);
1095 return; // closing session, PPP not processed
1096 }
1097
1098 session[s].last_packet = session[s].last_data = time_now;
1099 processipv6in(s, t, p, l);
1100 }
1101 else
1102 {
1103 LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
1104 }
1105 }
1106
1107 // process outgoing (to tunnel) IP
1108 //
1109 static void processipout(uint8_t *buf, int len)
1110 {
1111 sessionidt s;
1112 sessiont *sp;
1113 tunnelidt t;
1114 in_addr_t ip;
1115
1116 uint8_t *data = buf; // Keep a copy of the originals.
1117 int size = len;
1118
1119 uint8_t b1[MAXETHER + 20];
1120 uint8_t b2[MAXETHER + 20];
1121
1122 CSTAT(processipout);
1123
1124 if (len < MIN_IP_SIZE)
1125 {
1126 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1127 STAT(tun_rx_errors);
1128 return;
1129 }
1130 if (len >= MAXETHER)
1131 {
1132 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1133 STAT(tun_rx_errors);
1134 return;
1135 }
1136
1137 // Skip the tun header
1138 buf += 4;
1139 len -= 4;
1140
1141 // Got an IP header now
1142 if (*(uint8_t *)(buf) >> 4 != 4)
1143 {
1144 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1145 return;
1146 }
1147
1148 ip = *(uint32_t *)(buf + 16);
1149 if (!(s = sessionbyip(ip)))
1150 {
1151 // Is this a packet for a session that doesn't exist?
1152 static int rate = 0; // Number of ICMP packets we've sent this second.
1153 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1154
1155 if (last != time_now)
1156 {
1157 last = time_now;
1158 rate = 0;
1159 }
1160
1161 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1162 {
1163 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1164 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1165 config->bind_address ? config->bind_address : my_address, buf, len);
1166 }
1167 return;
1168 }
1169 t = session[s].tunnel;
1170 sp = &session[s];
1171 sp->last_data = time_now;
1172
1173 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1174 if (config->max_packets > 0)
1175 {
1176 if (sess_local[s].last_packet_out == TIME)
1177 {
1178 int max = config->max_packets;
1179
1180 // All packets for throttled sessions are handled by the
1181 // master, so further limit by using the throttle rate.
1182 // A bit of a kludge, since throttle rate is in kbps,
1183 // but should still be generous given our average DSL
1184 // packet size is 200 bytes: a limit of 28kbps equates
1185 // to around 180 packets per second.
1186 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1187 max = sp->throttle_out;
1188
1189 if (++sess_local[s].packets_out > max)
1190 {
1191 sess_local[s].packets_dropped++;
1192 return;
1193 }
1194 }
1195 else
1196 {
1197 if (sess_local[s].packets_dropped)
1198 {
1199 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1200 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1201 sess_local[s].packets_dropped, sess_local[s].packets_out,
1202 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1203 sp->user);
1204 }
1205
1206 sess_local[s].last_packet_out = TIME;
1207 sess_local[s].packets_out = 1;
1208 sess_local[s].packets_dropped = 0;
1209 }
1210 }
1211
1212 // run access-list if any
1213 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1214 return;
1215
1216 // adjust MSS on SYN and SYN,ACK packets with options
1217 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1218 {
1219 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1220 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1221 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1222 }
1223
1224 if (sp->tbf_out)
1225 {
1226 // Are we throttling this session?
1227 if (config->cluster_iam_master)
1228 tbf_queue_packet(sp->tbf_out, data, size);
1229 else
1230 master_throttle_packet(sp->tbf_out, data, size);
1231 return;
1232 }
1233
1234 if (sp->walled_garden && !config->cluster_iam_master)
1235 {
1236 // We are walled-gardening this
1237 master_garden_packet(s, data, size);
1238 return;
1239 }
1240
1241 // Add on L2TP header
1242 {
1243 bundleidt bid = 0;
1244 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1245 {
1246 bid = session[s].bundle;
1247 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1248 LOG(4, s, t, "MPPP: (1)Session number becomes: %u\n", s);
1249 if (len > 256)
1250 {
1251 // Partition the packet to 2 fragments
1252 uint32_t frag1len = len / 2;
1253 uint32_t frag2len = len - frag1len;
1254 uint8_t *p = makeppp(b1, sizeof(b1), buf, frag1len, s, t, PPPIP, 0, bid, MP_BEGIN);
1255 uint8_t *q;
1256
1257 if (!p) return;
1258 tunnelsend(b1, frag1len + (p-b1), t); // send it...
1259 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1260 LOG(4, s, t, "MPPP: (2)Session number becomes: %u\n", s);
1261 q = makeppp(b2, sizeof(b2), buf+frag1len, frag2len, s, t, PPPIP, 0, bid, MP_END);
1262 if (!q) return;
1263 tunnelsend(b2, frag2len + (q-b2), t); // send it...
1264 }
1265 else {
1266 // Send it as one frame
1267 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
1268 if (!p) return;
1269 tunnelsend(b1, len + (p-b1), t); // send it...
1270 }
1271 }
1272 else
1273 {
1274 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, 0, 0);
1275 if (!p) return;
1276 tunnelsend(b1, len + (p-b1), t); // send it...
1277 }
1278 }
1279
1280 // Snooping this session, send it to intercept box
1281 if (sp->snoop_ip && sp->snoop_port)
1282 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1283
1284 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1285 sp->cout_delta += len;
1286 sp->pout++;
1287 udp_tx += len;
1288
1289 sess_local[s].cout += len; // To send to master..
1290 sess_local[s].pout++;
1291 }
1292
1293 // process outgoing (to tunnel) IPv6
1294 //
1295 static void processipv6out(uint8_t * buf, int len)
1296 {
1297 sessionidt s;
1298 sessiont *sp;
1299 tunnelidt t;
1300 in_addr_t ip;
1301 struct in6_addr ip6;
1302
1303 uint8_t *data = buf; // Keep a copy of the originals.
1304 int size = len;
1305
1306 uint8_t b[MAXETHER + 20];
1307
1308 CSTAT(processipv6out);
1309
1310 if (len < MIN_IP_SIZE)
1311 {
1312 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1313 STAT(tunnel_tx_errors);
1314 return;
1315 }
1316 if (len >= MAXETHER)
1317 {
1318 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1319 STAT(tunnel_tx_errors);
1320 return;
1321 }
1322
1323 // Skip the tun header
1324 buf += 4;
1325 len -= 4;
1326
1327 // Got an IP header now
1328 if (*(uint8_t *)(buf) >> 4 != 6)
1329 {
1330 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1331 return;
1332 }
1333
1334 ip6 = *(struct in6_addr *)(buf+24);
1335 s = sessionbyipv6(ip6);
1336
1337 if (s == 0)
1338 {
1339 ip = *(uint32_t *)(buf + 32);
1340 s = sessionbyip(ip);
1341 }
1342
1343 if (s == 0)
1344 {
1345 // Is this a packet for a session that doesn't exist?
1346 static int rate = 0; // Number of ICMP packets we've sent this second.
1347 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1348
1349 if (last != time_now)
1350 {
1351 last = time_now;
1352 rate = 0;
1353 }
1354
1355 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1356 {
1357 // FIXME: Should send icmp6 host unreachable
1358 }
1359 return;
1360 }
1361 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1362 {
1363 bundleidt bid = session[s].bundle;
1364 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1365 LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %u\n", s);
1366 }
1367 t = session[s].tunnel;
1368 sp = &session[s];
1369 sp->last_data = time_now;
1370
1371 // FIXME: add DoS prevention/filters?
1372
1373 if (sp->tbf_out)
1374 {
1375 // Are we throttling this session?
1376 if (config->cluster_iam_master)
1377 tbf_queue_packet(sp->tbf_out, data, size);
1378 else
1379 master_throttle_packet(sp->tbf_out, data, size);
1380 return;
1381 }
1382 else if (sp->walled_garden && !config->cluster_iam_master)
1383 {
1384 // We are walled-gardening this
1385 master_garden_packet(s, data, size);
1386 return;
1387 }
1388
1389 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1390
1391 // Add on L2TP header
1392 {
1393 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
1394 if (!p) return;
1395 tunnelsend(b, len + (p-b), t); // send it...
1396 }
1397
1398 // Snooping this session, send it to intercept box
1399 if (sp->snoop_ip && sp->snoop_port)
1400 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1401
1402 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1403 sp->cout_delta += len;
1404 sp->pout++;
1405 udp_tx += len;
1406
1407 sess_local[s].cout += len; // To send to master..
1408 sess_local[s].pout++;
1409 }
1410
1411 //
1412 // Helper routine for the TBF filters.
1413 // Used to send queued data in to the user!
1414 //
1415 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1416 {
1417 sessiont *sp;
1418 tunnelidt t;
1419 in_addr_t ip;
1420
1421 uint8_t b[MAXETHER + 20];
1422
1423 if (len < 0 || len > MAXETHER)
1424 {
1425 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1426 return;
1427 }
1428
1429 // Skip the tun header
1430 buf += 4;
1431 len -= 4;
1432
1433 ip = *(in_addr_t *)(buf + 16);
1434
1435 if (!session[s].ip)
1436 return;
1437
1438 t = session[s].tunnel;
1439 sp = &session[s];
1440
1441 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1442
1443 // Add on L2TP header
1444 {
1445 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
1446 if (!p) return;
1447 tunnelsend(b, len + (p-b), t); // send it...
1448 }
1449
1450 // Snooping this session.
1451 if (sp->snoop_ip && sp->snoop_port)
1452 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1453
1454 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1455 sp->cout_delta += len;
1456 sp->pout++;
1457 udp_tx += len;
1458
1459 sess_local[s].cout += len; // To send to master..
1460 sess_local[s].pout++;
1461 }
1462
1463 // add an AVP (16 bit)
1464 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1465 {
1466 uint16_t l = (m ? 0x8008 : 0x0008);
1467 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1468 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1469 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1470 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1471 c->length += 8;
1472 }
1473
1474 // add an AVP (32 bit)
1475 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1476 {
1477 uint16_t l = (m ? 0x800A : 0x000A);
1478 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1479 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1480 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1481 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1482 c->length += 10;
1483 }
1484
1485 // add an AVP (string)
1486 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1487 {
1488 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1489 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1490 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1491 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1492 memcpy(c->buf + c->length + 6, val, strlen(val));
1493 c->length += 6 + strlen(val);
1494 }
1495
1496 // add a binary AVP
1497 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1498 {
1499 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1500 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1501 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1502 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1503 memcpy(c->buf + c->length + 6, val, len);
1504 c->length += 6 + len;
1505 }
1506
1507 // new control connection
1508 static controlt *controlnew(uint16_t mtype)
1509 {
1510 controlt *c;
1511 if (!controlfree)
1512 c = malloc(sizeof(controlt));
1513 else
1514 {
1515 c = controlfree;
1516 controlfree = c->next;
1517 }
1518 assert(c);
1519 c->next = 0;
1520 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1521 c->length = 12;
1522 control16(c, 0, mtype, 1);
1523 return c;
1524 }
1525
1526 // send zero block if nothing is waiting
1527 // (ZLB send).
1528 static void controlnull(tunnelidt t)
1529 {
1530 uint8_t buf[12];
1531 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1532 return;
1533
1534 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1535 *(uint16_t *) (buf + 2) = htons(12); // length
1536 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1537 *(uint16_t *) (buf + 6) = htons(0); // session
1538 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1539 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1540 tunnelsend(buf, 12, t);
1541 }
1542
1543 // add a control message to a tunnel, and send if within window
1544 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1545 {
1546 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1547 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1548 *(uint16_t *) (c->buf + 6) = htons(far); // session
1549 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1550 tunnel[t].ns++; // advance sequence
1551 // link in message in to queue
1552 if (tunnel[t].controlc)
1553 tunnel[t].controle->next = c;
1554 else
1555 tunnel[t].controls = c;
1556
1557 tunnel[t].controle = c;
1558 tunnel[t].controlc++;
1559
1560 // send now if space in window
1561 if (tunnel[t].controlc <= tunnel[t].window)
1562 {
1563 tunnel[t].try = 0; // first send
1564 tunnelsend(c->buf, c->length, t);
1565 }
1566 }
1567
1568 //
1569 // Throttle or Unthrottle a session
1570 //
1571 // Throttle the data from/to through a session to no more than
1572 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1573 // user).
1574 //
1575 // If either value is -1, the current value is retained for that
1576 // direction.
1577 //
1578 void throttle_session(sessionidt s, int rate_in, int rate_out)
1579 {
1580 if (!session[s].opened)
1581 return; // No-one home.
1582
1583 if (!*session[s].user)
1584 return; // User not logged in
1585
1586 if (rate_in >= 0)
1587 {
1588 int bytes = rate_in * 1024 / 8; // kbits to bytes
1589 if (session[s].tbf_in)
1590 free_tbf(session[s].tbf_in);
1591
1592 if (rate_in > 0)
1593 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1594 else
1595 session[s].tbf_in = 0;
1596
1597 session[s].throttle_in = rate_in;
1598 }
1599
1600 if (rate_out >= 0)
1601 {
1602 int bytes = rate_out * 1024 / 8;
1603 if (session[s].tbf_out)
1604 free_tbf(session[s].tbf_out);
1605
1606 if (rate_out > 0)
1607 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1608 else
1609 session[s].tbf_out = 0;
1610
1611 session[s].throttle_out = rate_out;
1612 }
1613 }
1614
1615 // add/remove filters from session (-1 = no change)
1616 void filter_session(sessionidt s, int filter_in, int filter_out)
1617 {
1618 if (!session[s].opened)
1619 return; // No-one home.
1620
1621 if (!*session[s].user)
1622 return; // User not logged in
1623
1624 // paranoia
1625 if (filter_in > MAXFILTER) filter_in = -1;
1626 if (filter_out > MAXFILTER) filter_out = -1;
1627 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1628 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1629
1630 if (filter_in >= 0)
1631 {
1632 if (session[s].filter_in)
1633 ip_filters[session[s].filter_in - 1].used--;
1634
1635 if (filter_in > 0)
1636 ip_filters[filter_in - 1].used++;
1637
1638 session[s].filter_in = filter_in;
1639 }
1640
1641 if (filter_out >= 0)
1642 {
1643 if (session[s].filter_out)
1644 ip_filters[session[s].filter_out - 1].used--;
1645
1646 if (filter_out > 0)
1647 ip_filters[filter_out - 1].used++;
1648
1649 session[s].filter_out = filter_out;
1650 }
1651 }
1652
1653 // start tidy shutdown of session
1654 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
1655 {
1656 int walled_garden = session[s].walled_garden;
1657
1658
1659 CSTAT(sessionshutdown);
1660
1661 if (!session[s].opened)
1662 {
1663 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1664 return; // not a live session
1665 }
1666
1667 if (!session[s].die)
1668 {
1669 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1670 LOG(2, s, session[s].tunnel, "Shutting down session %u: %s\n", s, reason);
1671 run_plugins(PLUGIN_KILL_SESSION, &data);
1672 }
1673
1674 if (session[s].ip && !walled_garden && !session[s].die)
1675 {
1676 // RADIUS Stop message
1677 uint16_t r = radiusnew(s);
1678 if (r)
1679 {
1680 // stop, if not already trying
1681 if (radius[r].state != RADIUSSTOP)
1682 {
1683 radius[r].term_cause = term_cause;
1684 radius[r].term_msg = reason;
1685 radiussend(r, RADIUSSTOP);
1686 }
1687 }
1688 else
1689 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1690
1691 // Save counters to dump to accounting file
1692 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1693 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1694 }
1695
1696 if (session[s].ip)
1697 { // IP allocated, clear and unroute
1698 int r;
1699 int routed = 0;
1700 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1701 {
1702 if ((session[s].ip & session[s].route[r].mask) ==
1703 (session[s].route[r].ip & session[s].route[r].mask))
1704 routed++;
1705
1706 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1707 session[s].route[r].ip = 0;
1708 }
1709
1710 if (session[s].ip_pool_index == -1) // static ip
1711 {
1712 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1713 session[s].ip = 0;
1714 }
1715 else
1716 free_ip_address(s);
1717
1718 // unroute IPv6, if setup
1719 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1720 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1721 }
1722
1723 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1724 throttle_session(s, 0, 0);
1725
1726 if (cdn_result)
1727 { // Send CDN
1728 controlt *c = controlnew(14); // sending CDN
1729 if (cdn_error)
1730 {
1731 uint8_t buf[4];
1732 *(uint16_t *) buf = htons(cdn_result);
1733 *(uint16_t *) (buf+2) = htons(cdn_error);
1734 controlb(c, 1, buf, 4, 1);
1735 }
1736 else
1737 control16(c, 1, cdn_result, 1);
1738
1739 control16(c, 14, s, 1); // assigned session (our end)
1740 controladd(c, session[s].far, session[s].tunnel); // send the message
1741 }
1742
1743 if (!session[s].die)
1744 session[s].die = TIME + 150; // Clean up in 15 seconds
1745
1746 // update filter refcounts
1747 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1748 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1749
1750 // clear PPP state
1751 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1752 sess_local[s].lcp.restart = 0;
1753 sess_local[s].ipcp.restart = 0;
1754 sess_local[s].ipv6cp.restart = 0;
1755 sess_local[s].ccp.restart = 0;
1756
1757 cluster_send_session(s);
1758 }
1759
1760 void sendipcp(sessionidt s, tunnelidt t)
1761 {
1762 uint8_t buf[MAXETHER];
1763 uint8_t *q;
1764
1765 CSTAT(sendipcp);
1766 LOG(3, s, t, "IPCP: send ConfigReq\n");
1767
1768 if (!session[s].unique_id)
1769 {
1770 if (!++last_id) ++last_id; // skip zero
1771 session[s].unique_id = last_id;
1772 }
1773
1774 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
1775 if (!q) return;
1776
1777 *q = ConfigReq;
1778 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1779 *(uint16_t *) (q + 2) = htons(10); // packet length
1780 q[4] = 3; // ip address option
1781 q[5] = 6; // option length
1782 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1783 config->bind_address ? config->bind_address :
1784 my_address; // send my IP
1785
1786 tunnelsend(buf, 10 + (q - buf), t); // send it
1787 restart_timer(s, ipcp);
1788 }
1789
1790 void sendipv6cp(sessionidt s, tunnelidt t)
1791 {
1792 uint8_t buf[MAXETHER];
1793 uint8_t *q;
1794
1795 CSTAT(sendipv6cp);
1796 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1797
1798 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
1799 if (!q) return;
1800
1801 *q = ConfigReq;
1802 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1803 // only send one type
1804 // of request
1805 *(uint16_t *) (q + 2) = htons(14);
1806 q[4] = 1; // interface identifier option
1807 q[5] = 10; // option length
1808 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1809 *(uint32_t *) (q + 10) = 0;
1810 q[13] = 1;
1811
1812 tunnelsend(buf, 14 + (q - buf), t); // send it
1813 restart_timer(s, ipv6cp);
1814 }
1815
1816 static void sessionclear(sessionidt s)
1817 {
1818 memset(&session[s], 0, sizeof(session[s]));
1819 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1820 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1821
1822 session[s].tunnel = T_FREE; // Mark it as free.
1823 session[s].next = sessionfree;
1824 sessionfree = s;
1825 }
1826
1827 // kill a session now
1828 void sessionkill(sessionidt s, char *reason)
1829 {
1830 bundleidt b;
1831
1832 CSTAT(sessionkill);
1833
1834 if (!session[s].opened) // not alive
1835 return;
1836
1837 if (session[s].next)
1838 {
1839 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%u)\n", session[s].next);
1840 return;
1841 }
1842
1843 session[s].die = TIME;
1844 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
1845 if (sess_local[s].radius)
1846 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1847
1848 LOG(2, s, session[s].tunnel, "Kill session %u (%s): %s\n", s, session[s].user, reason);
1849 if ((b = session[s].bundle))
1850 {
1851 // This session was part of a bundle
1852 bundle[b].num_of_links--;
1853 LOG(3, s, 0, "MPPP: Dropping member link: %u from bundle %u\n", s, b);
1854 if (bundle[b].num_of_links == 0)
1855 {
1856 bundleclear(b);
1857 LOG(3, s, 0, "MPPP: Kill bundle: %u (No remaing member links)\n", b);
1858 }
1859 else
1860 {
1861 // Adjust the members array to accomodate the new change
1862 uint8_t mem_num = 0;
1863 // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
1864 if (bundle[b].members[bundle[b].num_of_links] != s)
1865 {
1866 uint8_t ml;
1867 for (ml = 0; ml<bundle[b].num_of_links; ml++)
1868 {
1869 if (bundle[b].members[ml] == s)
1870 {
1871 mem_num = ml;
1872 break;
1873 }
1874 }
1875 bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
1876 LOG(3, s, 0, "MPPP: Adjusted member links array\n");
1877 }
1878 }
1879 cluster_send_bundle(b);
1880 }
1881 sessionclear(s);
1882 cluster_send_session(s);
1883 }
1884
1885 static void tunnelclear(tunnelidt t)
1886 {
1887 if (!t) return;
1888 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1889 tunnel[t].state = TUNNELFREE;
1890 }
1891
1892 static void bundleclear(bundleidt b)
1893 {
1894 if (!b) return;
1895 memset(&bundle[b], 0, sizeof(bundle[b]));
1896 bundle[b].state = BUNDLEFREE;
1897 }
1898
1899 // kill a tunnel now
1900 static void tunnelkill(tunnelidt t, char *reason)
1901 {
1902 sessionidt s;
1903 controlt *c;
1904
1905 CSTAT(tunnelkill);
1906
1907 tunnel[t].state = TUNNELDIE;
1908
1909 // free control messages
1910 while ((c = tunnel[t].controls))
1911 {
1912 controlt * n = c->next;
1913 tunnel[t].controls = n;
1914 tunnel[t].controlc--;
1915 c->next = controlfree;
1916 controlfree = c;
1917 }
1918 // kill sessions
1919 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1920 if (session[s].tunnel == t)
1921 sessionkill(s, reason);
1922
1923 // free tunnel
1924 tunnelclear(t);
1925 LOG(1, 0, t, "Kill tunnel %u: %s\n", t, reason);
1926 cli_tunnel_actions[t].action = 0;
1927 cluster_send_tunnel(t);
1928 }
1929
1930 // shut down a tunnel cleanly
1931 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1932 {
1933 sessionidt s;
1934
1935 CSTAT(tunnelshutdown);
1936
1937 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1938 {
1939 // never set up, can immediately kill
1940 tunnelkill(t, reason);
1941 return;
1942 }
1943 LOG(1, 0, t, "Shutting down tunnel %u (%s)\n", t, reason);
1944
1945 // close session
1946 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1947 if (session[s].tunnel == t)
1948 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
1949
1950 tunnel[t].state = TUNNELDIE;
1951 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1952 cluster_send_tunnel(t);
1953 // TBA - should we wait for sessions to stop?
1954 if (result)
1955 {
1956 controlt *c = controlnew(4); // sending StopCCN
1957 if (error)
1958 {
1959 uint8_t buf[64];
1960 int l = 4;
1961 *(uint16_t *) buf = htons(result);
1962 *(uint16_t *) (buf+2) = htons(error);
1963 if (msg)
1964 {
1965 int m = strlen(msg);
1966 if (m + 4 > sizeof(buf))
1967 m = sizeof(buf) - 4;
1968
1969 memcpy(buf+4, msg, m);
1970 l += m;
1971 }
1972
1973 controlb(c, 1, buf, l, 1);
1974 }
1975 else
1976 control16(c, 1, result, 1);
1977
1978 control16(c, 9, t, 1); // assigned tunnel (our end)
1979 controladd(c, 0, t); // send the message
1980 }
1981 }
1982
1983 // read and process packet on tunnel (UDP)
1984 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1985 {
1986 uint8_t *chapresponse = NULL;
1987 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1988 uint8_t *p = buf + 2;
1989
1990
1991 CSTAT(processudp);
1992
1993 udp_rx += len;
1994 udp_rx_pkt++;
1995 LOG_HEX(5, "UDP Data", buf, len);
1996 STAT(tunnel_rx_packets);
1997 INC_STAT(tunnel_rx_bytes, len);
1998 if (len < 6)
1999 {
2000 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
2001 STAT(tunnel_rx_errors);
2002 return;
2003 }
2004 if ((buf[1] & 0x0F) != 2)
2005 {
2006 LOG(1, 0, 0, "Bad L2TP ver %d\n", buf[1] & 0x0F);
2007 STAT(tunnel_rx_errors);
2008 return;
2009 }
2010 if (*buf & 0x40)
2011 { // length
2012 l = ntohs(*(uint16_t *) p);
2013 p += 2;
2014 }
2015 t = ntohs(*(uint16_t *) p);
2016 p += 2;
2017 s = ntohs(*(uint16_t *) p);
2018 p += 2;
2019 if (s >= MAXSESSION)
2020 {
2021 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
2022 STAT(tunnel_rx_errors);
2023 return;
2024 }
2025 if (t >= MAXTUNNEL)
2026 {
2027 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
2028 STAT(tunnel_rx_errors);
2029 return;
2030 }
2031 if (*buf & 0x08)
2032 { // ns/nr
2033 ns = ntohs(*(uint16_t *) p);
2034 p += 2;
2035 nr = ntohs(*(uint16_t *) p);
2036 p += 2;
2037 }
2038 if (*buf & 0x02)
2039 { // offset
2040 uint16_t o = ntohs(*(uint16_t *) p);
2041 p += o + 2;
2042 }
2043 if ((p - buf) > l)
2044 {
2045 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
2046 STAT(tunnel_rx_errors);
2047 return;
2048 }
2049 l -= (p - buf);
2050
2051 // used to time out old tunnels
2052 if (t && tunnel[t].state == TUNNELOPEN)
2053 tunnel[t].lastrec = time_now;
2054
2055 if (*buf & 0x80)
2056 { // control
2057 uint16_t message = 0xFFFF; // message type
2058 uint8_t fatal = 0;
2059 uint8_t mandatory = 0;
2060 uint16_t asession = 0; // assigned session
2061 uint32_t amagic = 0; // magic number
2062 uint8_t aflags = 0; // flags from last LCF
2063 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
2064 char called[MAXTEL] = ""; // called number
2065 char calling[MAXTEL] = ""; // calling number
2066
2067 if (!config->cluster_iam_master)
2068 {
2069 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2070 return;
2071 }
2072
2073 // control messages must have bits 0x80|0x40|0x08
2074 // (type, length and sequence) set, and bits 0x02|0x01
2075 // (offset and priority) clear
2076 if ((*buf & 0xCB) != 0xC8)
2077 {
2078 LOG(1, s, t, "Bad control header %02X\n", *buf);
2079 STAT(tunnel_rx_errors);
2080 return;
2081 }
2082
2083 // check for duplicate tunnel open message
2084 if (!t && ns == 0)
2085 {
2086 int i;
2087
2088 //
2089 // Is this a duplicate of the first packet? (SCCRQ)
2090 //
2091 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
2092 {
2093 if (tunnel[i].state != TUNNELOPENING ||
2094 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
2095 tunnel[i].port != ntohs(addr->sin_port) )
2096 continue;
2097 t = i;
2098 LOG(3, s, t, "Duplicate SCCRQ?\n");
2099 break;
2100 }
2101 }
2102
2103 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %u l-nr %u r-ns %u r-nr %u\n",
2104 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
2105
2106 // if no tunnel specified, assign one
2107 if (!t)
2108 {
2109 if (!(t = new_tunnel()))
2110 {
2111 LOG(1, 0, 0, "No more tunnels\n");
2112 STAT(tunnel_overflow);
2113 return;
2114 }
2115 tunnelclear(t);
2116 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
2117 tunnel[t].port = ntohs(addr->sin_port);
2118 tunnel[t].window = 4; // default window
2119 STAT(tunnel_created);
2120 LOG(1, 0, t, " New tunnel from %s:%u ID %u\n",
2121 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
2122 }
2123
2124 // If the 'ns' just received is not the 'nr' we're
2125 // expecting, just send an ack and drop it.
2126 //
2127 // if 'ns' is less, then we got a retransmitted packet.
2128 // if 'ns' is greater than missed a packet. Either way
2129 // we should ignore it.
2130 if (ns != tunnel[t].nr)
2131 {
2132 // is this the sequence we were expecting?
2133 STAT(tunnel_rx_errors);
2134 LOG(1, 0, t, " Out of sequence tunnel %u, (%u is not the expected %u)\n",
2135 t, ns, tunnel[t].nr);
2136
2137 if (l) // Is this not a ZLB?
2138 controlnull(t);
2139 return;
2140 }
2141
2142 // check sequence of this message
2143 {
2144 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2145 // some to clear maybe?
2146 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2147 {
2148 controlt *c = tunnel[t].controls;
2149 tunnel[t].controls = c->next;
2150 tunnel[t].controlc--;
2151 c->next = controlfree;
2152 controlfree = c;
2153 skip--;
2154 tunnel[t].try = 0; // we have progress
2155 }
2156
2157 // receiver advance (do here so quoted correctly in any sends below)
2158 if (l) tunnel[t].nr = (ns + 1);
2159 if (skip < 0) skip = 0;
2160 if (skip < tunnel[t].controlc)
2161 {
2162 // some control packets can now be sent that were previous stuck out of window
2163 int tosend = tunnel[t].window - skip;
2164 controlt *c = tunnel[t].controls;
2165 while (c && skip)
2166 {
2167 c = c->next;
2168 skip--;
2169 }
2170 while (c && tosend)
2171 {
2172 tunnel[t].try = 0; // first send
2173 tunnelsend(c->buf, c->length, t);
2174 c = c->next;
2175 tosend--;
2176 }
2177 }
2178 if (!tunnel[t].controlc)
2179 tunnel[t].retry = 0; // caught up
2180 }
2181 if (l)
2182 { // if not a null message
2183 int result = 0;
2184 int error = 0;
2185 char *msg = 0;
2186
2187 // default disconnect cause/message on receipt
2188 // of CDN (set to more specific value from
2189 // attribute 46 if present below).
2190 int disc_cause = TERM_NAS_REQUEST;
2191 char const *disc_reason = "Closed (Received CDN).";
2192
2193 // process AVPs
2194 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2195 {
2196 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2197 uint8_t *b = p;
2198 uint8_t flags = *p;
2199 uint16_t mtype;
2200
2201 if (n > l)
2202 {
2203 LOG(1, s, t, "Invalid length in AVP\n");
2204 STAT(tunnel_rx_errors);
2205 return;
2206 }
2207 p += n; // next
2208 l -= n;
2209 if (flags & 0x3C) // reserved bits, should be clear
2210 {
2211 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2212 fatal = flags;
2213 result = 2; // general error
2214 error = 3; // reserved field non-zero
2215 msg = 0;
2216 continue; // next
2217 }
2218 b += 2;
2219 if (*(uint16_t *) (b))
2220 {
2221 LOG(2, s, t, "Unknown AVP vendor %u\n", ntohs(*(uint16_t *) (b)));
2222 fatal = flags;
2223 result = 2; // general error
2224 error = 6; // generic vendor-specific error
2225 msg = "unsupported vendor-specific";
2226 continue; // next
2227 }
2228 b += 2;
2229 mtype = ntohs(*(uint16_t *) (b));
2230 b += 2;
2231 n -= 6;
2232
2233 if (flags & 0x40)
2234 {
2235 uint16_t orig_len;
2236
2237 // handle hidden AVPs
2238 if (!*config->l2tp_secret)
2239 {
2240 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2241 fatal = flags;
2242 result = 2; // general error
2243 error = 6; // generic vendor-specific error
2244 msg = "secret not specified";
2245 continue;
2246 }
2247 if (!session[s].random_vector_length)
2248 {
2249 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2250 fatal = flags;
2251 result = 2; // general error
2252 error = 6; // generic
2253 msg = "no random vector";
2254 continue;
2255 }
2256 if (n < 8)
2257 {
2258 LOG(2, s, t, "Short hidden AVP.\n");
2259 fatal = flags;
2260 result = 2; // general error
2261 error = 2; // length is wrong
2262 msg = 0;
2263 continue;
2264 }
2265
2266 // Unhide the AVP
2267 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2268
2269 orig_len = ntohs(*(uint16_t *) b);
2270 if (orig_len > n + 2)
2271 {
2272 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2273 orig_len, n);
2274
2275 fatal = flags;
2276 result = 2; // general error
2277 error = 2; // length is wrong
2278 msg = 0;
2279 continue;
2280 }
2281
2282 b += 2;
2283 n = orig_len;
2284 }
2285
2286 LOG(4, s, t, " AVP %u (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2287 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2288
2289 switch (mtype)
2290 {
2291 case 0: // message type
2292 message = ntohs(*(uint16_t *) b);
2293 mandatory = flags & 0x80;
2294 LOG(4, s, t, " Message type = %u (%s)\n", *b, l2tp_code(message));
2295 break;
2296 case 1: // result code
2297 {
2298 uint16_t rescode = ntohs(*(uint16_t *) b);
2299 const char* resdesc = "(unknown)";
2300 if (message == 4)
2301 { /* StopCCN */
2302 resdesc = l2tp_stopccn_result_code(rescode);
2303 }
2304 else if (message == 14)
2305 { /* CDN */
2306 resdesc = l2tp_cdn_result_code(rescode);
2307 }
2308
2309 LOG(4, s, t, " Result Code %u: %s\n", rescode, resdesc);
2310 if (n >= 4)
2311 {
2312 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2313 LOG(4, s, t, " Error Code %u: %s\n", errcode, l2tp_error_code(errcode));
2314 }
2315 if (n > 4)
2316 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2317
2318 break;
2319 }
2320 break;
2321 case 2: // protocol version
2322 {
2323 version = ntohs(*(uint16_t *) (b));
2324 LOG(4, s, t, " Protocol version = %u\n", version);
2325 if (version && version != 0x0100)
2326 { // allow 0.0 and 1.0
2327 LOG(1, s, t, " Bad protocol version %04X\n", version);
2328 fatal = flags;
2329 result = 5; // unspported protocol version
2330 error = 0x0100; // supported version
2331 msg = 0;
2332 continue; // next
2333 }
2334 }
2335 break;
2336 case 3: // framing capabilities
2337 break;
2338 case 4: // bearer capabilities
2339 break;
2340 case 5: // tie breaker
2341 // We never open tunnels, so we don't care about tie breakers
2342 continue;
2343 case 6: // firmware revision
2344 break;
2345 case 7: // host name
2346 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2347 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2348 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2349 // TBA - to send to RADIUS
2350 break;
2351 case 8: // vendor name
2352 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2353 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2354 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2355 break;
2356 case 9: // assigned tunnel
2357 tunnel[t].far = ntohs(*(uint16_t *) (b));
2358 LOG(4, s, t, " Remote tunnel id = %u\n", tunnel[t].far);
2359 break;
2360 case 10: // rx window
2361 tunnel[t].window = ntohs(*(uint16_t *) (b));
2362 if (!tunnel[t].window)
2363 tunnel[t].window = 1; // window of 0 is silly
2364 LOG(4, s, t, " rx window = %u\n", tunnel[t].window);
2365 break;
2366 case 11: // Challenge
2367 {
2368 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2369 build_chap_response(b, 2, n, &chapresponse);
2370 }
2371 break;
2372 case 13: // Response
2373 // Why did they send a response? We never challenge.
2374 LOG(2, s, t, " received unexpected challenge response\n");
2375 break;
2376
2377 case 14: // assigned session
2378 asession = session[s].far = ntohs(*(uint16_t *) (b));
2379 LOG(4, s, t, " assigned session = %u\n", asession);
2380 break;
2381 case 15: // call serial number
2382 LOG(4, s, t, " call serial number = %u\n", ntohl(*(uint32_t *)b));
2383 break;
2384 case 18: // bearer type
2385 LOG(4, s, t, " bearer type = %u\n", ntohl(*(uint32_t *)b));
2386 // TBA - for RADIUS
2387 break;
2388 case 19: // framing type
2389 LOG(4, s, t, " framing type = %u\n", ntohl(*(uint32_t *)b));
2390 // TBA
2391 break;
2392 case 21: // called number
2393 memset(called, 0, sizeof(called));
2394 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2395 LOG(4, s, t, " Called <%s>\n", called);
2396 break;
2397 case 22: // calling number
2398 memset(calling, 0, sizeof(calling));
2399 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2400 LOG(4, s, t, " Calling <%s>\n", calling);
2401 break;
2402 case 23: // subtype
2403 break;
2404 case 24: // tx connect speed
2405 if (n == 4)
2406 {
2407 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2408 }
2409 else
2410 {
2411 // AS5300s send connect speed as a string
2412 char tmp[30];
2413 memset(tmp, 0, sizeof(tmp));
2414 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2415 session[s].tx_connect_speed = atol(tmp);
2416 }
2417 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2418 break;
2419 case 38: // rx connect speed
2420 if (n == 4)
2421 {
2422 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2423 }
2424 else
2425 {
2426 // AS5300s send connect speed as a string
2427 char tmp[30];
2428 memset(tmp, 0, sizeof(tmp));
2429 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2430 session[s].rx_connect_speed = atol(tmp);
2431 }
2432 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2433 break;
2434 case 25: // Physical Channel ID
2435 {
2436 uint32_t tmp = ntohl(*(uint32_t *) b);
2437 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2438 break;
2439 }
2440 case 29: // Proxy Authentication Type
2441 {
2442 uint16_t atype = ntohs(*(uint16_t *)b);
2443 LOG(4, s, t, " Proxy Auth Type %u (%s)\n", atype, ppp_auth_type(atype));
2444 break;
2445 }
2446 case 30: // Proxy Authentication Name
2447 {
2448 char authname[64];
2449 memset(authname, 0, sizeof(authname));
2450 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2451 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2452 authname);
2453 break;
2454 }
2455 case 31: // Proxy Authentication Challenge
2456 {
2457 LOG(4, s, t, " Proxy Auth Challenge\n");
2458 break;
2459 }
2460 case 32: // Proxy Authentication ID
2461 {
2462 uint16_t authid = ntohs(*(uint16_t *)(b));
2463 LOG(4, s, t, " Proxy Auth ID (%u)\n", authid);
2464 break;
2465 }
2466 case 33: // Proxy Authentication Response
2467 LOG(4, s, t, " Proxy Auth Response\n");
2468 break;
2469 case 27: // last sent lcp
2470 { // find magic number
2471 uint8_t *p = b, *e = p + n;
2472 while (p + 1 < e && p[1] && p + p[1] <= e)
2473 {
2474 if (*p == 5 && p[1] == 6) // Magic-Number
2475 amagic = ntohl(*(uint32_t *) (p + 2));
2476 else if (*p == 7) // Protocol-Field-Compression
2477 aflags |= SESSION_PFC;
2478 else if (*p == 8) // Address-and-Control-Field-Compression
2479 aflags |= SESSION_ACFC;
2480 p += p[1];
2481 }
2482 }
2483 break;
2484 case 28: // last recv lcp confreq
2485 break;
2486 case 26: // Initial Received LCP CONFREQ
2487 break;
2488 case 39: // seq required - we control it as an LNS anyway...
2489 break;
2490 case 36: // Random Vector
2491 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2492 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2493 if (n > sizeof(session[s].random_vector))
2494 n = sizeof(session[s].random_vector);
2495 memcpy(session[s].random_vector, b, n);
2496 session[s].random_vector_length = n;
2497 break;
2498 case 46: // ppp disconnect cause
2499 if (n >= 5)
2500 {
2501 uint16_t code = ntohs(*(uint16_t *) b);
2502 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2503 uint8_t dir = *(b + 4);
2504
2505 LOG(4, s, t, " PPP disconnect cause "
2506 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2507 code, proto, dir, n - 5, b + 5);
2508
2509 switch (code)
2510 {
2511 case 1: // admin disconnect
2512 disc_cause = TERM_ADMIN_RESET;
2513 disc_reason = "Administrative disconnect";
2514 break;
2515 case 3: // lcp terminate
2516 if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
2517 disc_cause = TERM_USER_REQUEST;
2518 disc_reason = "Normal disconnection";
2519 break;
2520 case 4: // compulsory encryption unavailable
2521 if (dir != 1) break; // 1=refused by peer, 2=local
2522 disc_cause = TERM_USER_ERROR;
2523 disc_reason = "Compulsory encryption refused";
2524 break;
2525 case 5: // lcp: fsm timeout
2526 disc_cause = TERM_PORT_ERROR;
2527 disc_reason = "LCP: FSM timeout";
2528 break;
2529 case 6: // lcp: no recognisable lcp packets received
2530 disc_cause = TERM_PORT_ERROR;
2531 disc_reason = "LCP: no recognisable LCP packets";
2532 break;
2533 case 7: // lcp: magic-no error (possibly looped back)
2534 disc_cause = TERM_PORT_ERROR;
2535 disc_reason = "LCP: magic-no error (possible loop)";
2536 break;
2537 case 8: // lcp: echo request timeout
2538 disc_cause = TERM_PORT_ERROR;
2539 disc_reason = "LCP: echo request timeout";
2540 break;
2541 case 13: // auth: fsm timeout
2542 disc_cause = TERM_SERVICE_UNAVAILABLE;
2543 disc_reason = "Authentication: FSM timeout";
2544 break;
2545 case 15: // auth: unacceptable auth protocol
2546 disc_cause = TERM_SERVICE_UNAVAILABLE;
2547 disc_reason = "Unacceptable authentication protocol";
2548 break;
2549 case 16: // auth: authentication failed
2550 disc_cause = TERM_SERVICE_UNAVAILABLE;
2551 disc_reason = "Authentication failed";
2552 break;
2553 case 17: // ncp: fsm timeout
2554 disc_cause = TERM_SERVICE_UNAVAILABLE;
2555 disc_reason = "NCP: FSM timeout";
2556 break;
2557 case 18: // ncp: no ncps available
2558 disc_cause = TERM_SERVICE_UNAVAILABLE;
2559 disc_reason = "NCP: no NCPs available";
2560 break;
2561 case 19: // ncp: failure to converge on acceptable address
2562 disc_cause = TERM_SERVICE_UNAVAILABLE;
2563 disc_reason = (dir == 1)
2564 ? "NCP: too many Configure-Naks received from peer"
2565 : "NCP: too many Configure-Naks sent to peer";
2566 break;
2567 case 20: // ncp: user not permitted to use any address
2568 disc_cause = TERM_SERVICE_UNAVAILABLE;
2569 disc_reason = (dir == 1)
2570 ? "NCP: local link address not acceptable to peer"
2571 : "NCP: remote link address not acceptable";
2572 break;
2573 }
2574 }
2575 break;
2576 default:
2577 {
2578 static char e[] = "unknown AVP 0xXXXX";
2579 LOG(2, s, t, " Unknown AVP type %u\n", mtype);
2580 fatal = flags;
2581 result = 2; // general error
2582 error = 8; // unknown mandatory AVP
2583 sprintf((msg = e) + 14, "%04x", mtype);
2584 continue; // next
2585 }
2586 }
2587 }
2588 // process message
2589 if (fatal & 0x80)
2590 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2591 else
2592 switch (message)
2593 {
2594 case 1: // SCCRQ - Start Control Connection Request
2595 tunnel[t].state = TUNNELOPENING;
2596 if (main_quit != QUIT_SHUTDOWN)
2597 {
2598 controlt *c = controlnew(2); // sending SCCRP
2599 control16(c, 2, version, 1); // protocol version
2600 control32(c, 3, 3, 1); // framing
2601 controls(c, 7, hostname, 1); // host name
2602 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2603 control16(c, 9, t, 1); // assigned tunnel
2604 controladd(c, 0, t); // send the resply
2605 }
2606 else
2607 {
2608 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2609 }
2610 break;
2611 case 2: // SCCRP
2612 tunnel[t].state = TUNNELOPEN;
2613 break;
2614 case 3: // SCCN
2615 tunnel[t].state = TUNNELOPEN;
2616 controlnull(t); // ack
2617 break;
2618 case 4: // StopCCN
2619 controlnull(t); // ack
2620 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2621 break;
2622 case 6: // HELLO
2623 controlnull(t); // simply ACK
2624 break;
2625 case 7: // OCRQ
2626 // TBA
2627 break;
2628 case 8: // OCRO
2629 // TBA
2630 break;
2631 case 9: // OCCN
2632 // TBA
2633 break;
2634 case 10: // ICRQ
2635 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2636 {
2637 controlt *c = controlnew(11); // ICRP
2638
2639 s = sessionfree;
2640 sessionfree = session[s].next;
2641 memset(&session[s], 0, sizeof(session[s]));
2642
2643 if (s > config->cluster_highest_sessionid)
2644 config->cluster_highest_sessionid = s;
2645
2646 session[s].opened = time_now;
2647 session[s].tunnel = t;
2648 session[s].far = asession;
2649 session[s].last_packet = session[s].last_data = time_now;
2650 LOG(3, s, t, "New session (%u/%u)\n", tunnel[t].far, session[s].far);
2651 control16(c, 14, s, 1); // assigned session
2652 controladd(c, asession, t); // send the reply
2653
2654 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2655 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2656
2657 session[s].ppp.phase = Establish;
2658 session[s].ppp.lcp = Starting;
2659
2660 STAT(session_created);
2661 break;
2662 }
2663
2664 {
2665 controlt *c = controlnew(14); // CDN
2666 if (!sessionfree)
2667 {
2668 STAT(session_overflow);
2669 LOG(1, 0, t, "No free sessions\n");
2670 control16(c, 1, 4, 0); // temporary lack of resources
2671 }
2672 else
2673 control16(c, 1, 2, 7); // shutting down, try another
2674
2675 controladd(c, asession, t); // send the message
2676 }
2677 return;
2678 case 11: // ICRP
2679 // TBA
2680 break;
2681 case 12: // ICCN
2682 if (amagic == 0) amagic = time_now;
2683 session[s].magic = amagic; // set magic number
2684 session[s].flags = aflags; // set flags received
2685 session[s].mru = PPPoE_MRU; // default
2686 controlnull(t); // ack
2687
2688 // start LCP
2689 sess_local[s].lcp_authtype = config->radius_authprefer;
2690 sess_local[s].ppp_mru = MRU;
2691
2692 // Set multilink options before sending initial LCP packet
2693 sess_local[s].mp_mrru = 1614;
2694 sess_local[s].mp_epdis = config->bind_address ? config->bind_address : my_address;
2695
2696 sendlcp(s, t);
2697 change_state(s, lcp, RequestSent);
2698 break;
2699
2700 case 14: // CDN
2701 controlnull(t); // ack
2702 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
2703 break;
2704 case 0xFFFF:
2705 LOG(1, s, t, "Missing message type\n");
2706 break;
2707 default:
2708 STAT(tunnel_rx_errors);
2709 if (mandatory)
2710 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2711 else
2712 LOG(1, s, t, "Unknown message type %u\n", message);
2713 break;
2714 }
2715 if (chapresponse) free(chapresponse);
2716 cluster_send_tunnel(t);
2717 }
2718 else
2719 {
2720 LOG(4, s, t, " Got a ZLB ack\n");
2721 }
2722 }
2723 else
2724 { // data
2725 uint16_t proto;
2726
2727 LOG_HEX(5, "Receive Tunnel Data", p, l);
2728 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2729 { // HDLC address header, discard
2730 p += 2;
2731 l -= 2;
2732 }
2733 if (l < 2)
2734 {
2735 LOG(1, s, t, "Short ppp length %d\n", l);
2736 STAT(tunnel_rx_errors);
2737 return;
2738 }
2739 if (*p & 1)
2740 {
2741 proto = *p++;
2742 l--;
2743 }
2744 else
2745 {
2746 proto = ntohs(*(uint16_t *) p);
2747 p += 2;
2748 l -= 2;
2749 }
2750
2751 if (s && !session[s].opened) // Is something wrong??
2752 {
2753 if (!config->cluster_iam_master)
2754 {
2755 // Pass it off to the master to deal with..
2756 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2757 return;
2758 }
2759
2760
2761 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2762 STAT(tunnel_rx_errors);
2763 return;
2764 }
2765
2766 if (proto == PPPPAP)
2767 {
2768 session[s].last_packet = time_now;
2769 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2770 processpap(s, t, p, l);
2771 }
2772 else if (proto == PPPCHAP)
2773 {
2774 session[s].last_packet = time_now;
2775 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2776 processchap(s, t, p, l);
2777 }
2778 else if (proto == PPPLCP)
2779 {
2780 session[s].last_packet = time_now;
2781 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2782 processlcp(s, t, p, l);
2783 }
2784 else if (proto == PPPIPCP)
2785 {
2786 session[s].last_packet = time_now;
2787 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2788 processipcp(s, t, p, l);
2789 }
2790 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2791 {
2792 session[s].last_packet = time_now;
2793 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2794 processipv6cp(s, t, p, l);
2795 }
2796 else if (proto == PPPCCP)
2797 {
2798 session[s].last_packet = time_now;
2799 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2800 processccp(s, t, p, l);
2801 }
2802 else if (proto == PPPIP)
2803 {
2804 if (session[s].die)
2805 {
2806 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2807 return; // closing session, PPP not processed
2808 }
2809
2810 session[s].last_packet = session[s].last_data = time_now;
2811 if (session[s].walled_garden && !config->cluster_iam_master)
2812 {
2813 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2814 return;
2815 }
2816
2817 processipin(s, t, p, l);
2818 }
2819 else if (proto == PPPMP)
2820 {
2821 if (session[s].die)
2822 {
2823 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2824 return; // closing session, PPP not processed
2825 }
2826
2827 session[s].last_packet = session[s].last_data = time_now;
2828 if (session[s].walled_garden && !config->cluster_iam_master)
2829 {
2830 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2831 return;
2832 }
2833
2834 processmpin(s, t, p, l);
2835 }
2836 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2837 {
2838 if (session[s].die)
2839 {
2840 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2841 return; // closing session, PPP not processed
2842 }
2843
2844 session[s].last_packet = session[s].last_data = time_now;
2845 if (session[s].walled_garden && !config->cluster_iam_master)
2846 {
2847 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2848 return;
2849 }
2850
2851 processipv6in(s, t, p, l);
2852 }
2853 else if (session[s].ppp.lcp == Opened)
2854 {
2855 session[s].last_packet = time_now;
2856 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2857 protoreject(s, t, p, l, proto);
2858 }
2859 else
2860 {
2861 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2862 proto, ppp_state(session[s].ppp.lcp));
2863 }
2864 }
2865 }
2866
2867 // read and process packet on tun
2868 static void processtun(uint8_t * buf, int len)
2869 {
2870 LOG_HEX(5, "Receive TUN Data", buf, len);
2871 STAT(tun_rx_packets);
2872 INC_STAT(tun_rx_bytes, len);
2873
2874 CSTAT(processtun);
2875
2876 eth_rx_pkt++;
2877 eth_rx += len;
2878 if (len < 22)
2879 {
2880 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2881 STAT(tun_rx_errors);
2882 return;
2883 }
2884
2885 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2886 processipout(buf, len);
2887 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2888 && config->ipv6_prefix.s6_addr[0])
2889 processipv6out(buf, len);
2890
2891 // Else discard.
2892 }
2893
2894 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2895 // that we look at the whole of the tunnel, radius and session tables
2896 // every second
2897 static void regular_cleanups(double period)
2898 {
2899 // Next tunnel, radius and session to check for actions on.
2900 static tunnelidt t = 0;
2901 static int r = 0;
2902 static sessionidt s = 0;
2903
2904 int t_actions = 0;
2905 int r_actions = 0;
2906 int s_actions = 0;
2907
2908 int t_slice;
2909 int r_slice;
2910 int s_slice;
2911
2912 int i;
2913 int a;
2914
2915 // divide up tables into slices based on the last run
2916 t_slice = config->cluster_highest_tunnelid * period;
2917 r_slice = (MAXRADIUS - 1) * period;
2918 s_slice = config->cluster_highest_sessionid * period;
2919
2920 if (t_slice < 1)
2921 t_slice = 1;
2922 else if (t_slice > config->cluster_highest_tunnelid)
2923 t_slice = config->cluster_highest_tunnelid;
2924
2925 if (r_slice < 1)
2926 r_slice = 1;
2927 else if (r_slice > (MAXRADIUS - 1))
2928 r_slice = MAXRADIUS - 1;
2929
2930 if (s_slice < 1)
2931 s_slice = 1;
2932 else if (s_slice > config->cluster_highest_sessionid)
2933 s_slice = config->cluster_highest_sessionid;
2934
2935 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2936
2937 for (i = 0; i < t_slice; i++)
2938 {
2939 t++;
2940 if (t > config->cluster_highest_tunnelid)
2941 t = 1;
2942
2943 // check for expired tunnels
2944 if (tunnel[t].die && tunnel[t].die <= TIME)
2945 {
2946 STAT(tunnel_timeout);
2947 tunnelkill(t, "Expired");
2948 t_actions++;
2949 continue;
2950 }
2951 // check for message resend
2952 if (tunnel[t].retry && tunnel[t].controlc)
2953 {
2954 // resend pending messages as timeout on reply
2955 if (tunnel[t].retry <= TIME)
2956 {
2957 controlt *c = tunnel[t].controls;
2958 uint8_t w = tunnel[t].window;
2959 tunnel[t].try++; // another try
2960 if (tunnel[t].try > 5)
2961 tunnelkill(t, "Timeout on control message"); // game over
2962 else
2963 while (c && w--)
2964 {
2965 tunnelsend(c->buf, c->length, t);
2966 c = c->next;
2967 }
2968
2969 t_actions++;
2970 }
2971 }
2972 // Send hello
2973 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2974 {
2975 controlt *c = controlnew(6); // sending HELLO
2976 controladd(c, 0, t); // send the message
2977 LOG(3, 0, t, "Sending HELLO message\n");
2978 t_actions++;
2979 }
2980
2981 // Check for tunnel changes requested from the CLI
2982 if ((a = cli_tunnel_actions[t].action))
2983 {
2984 cli_tunnel_actions[t].action = 0;
2985 if (a & CLI_TUN_KILL)
2986 {
2987 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2988 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2989 t_actions++;
2990 }
2991 }
2992 }
2993
2994 for (i = 0; i < r_slice; i++)
2995 {
2996 r++;
2997 if (r >= MAXRADIUS)
2998 r = 1;
2999
3000 if (!radius[r].state)
3001 continue;
3002
3003 if (radius[r].retry <= TIME)
3004 {
3005 radiusretry(r);
3006 r_actions++;
3007 }
3008 }
3009
3010 for (i = 0; i < s_slice; i++)
3011 {
3012 s++;
3013 if (s > config->cluster_highest_sessionid)
3014 s = 1;
3015
3016 if (!session[s].opened) // Session isn't in use
3017 continue;
3018
3019 // check for expired sessions
3020 if (session[s].die)
3021 {
3022 if (session[s].die <= TIME)
3023 {
3024 sessionkill(s, "Expired");
3025 s_actions++;
3026 }
3027 continue;
3028 }
3029
3030 // check for timed out sessions
3031 if (session[s].timeout)
3032 {
3033 bundleidt bid = session[s].bundle;
3034 if (bid)
3035 {
3036 clockt curr_time = time_now;
3037 if (curr_time - bundle[bid].last_check >= 1)
3038 {
3039 bundle[bid].online_time += (curr_time-bundle[bid].last_check)*bundle[bid].num_of_links;
3040 bundle[bid].last_check = curr_time;
3041 if (bundle[bid].online_time >= session[s].timeout)
3042 {
3043 int ses;
3044 for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
3045 {
3046 sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3047 s_actions++;
3048 continue;
3049 }
3050 }
3051 }
3052 }
3053 else if (session[s].timeout <= time_now - session[s].opened)
3054 {
3055 sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3056 s_actions++;
3057 continue;
3058 }
3059 }
3060
3061 // PPP timeouts
3062 if (sess_local[s].lcp.restart <= time_now)
3063 {
3064 int next_state = session[s].ppp.lcp;
3065 switch (session[s].ppp.lcp)
3066 {
3067 case RequestSent:
3068 case AckReceived:
3069 next_state = RequestSent;
3070
3071 case AckSent:
3072 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
3073 {
3074 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
3075 sendlcp(s, session[s].tunnel);
3076 change_state(s, lcp, next_state);
3077 }
3078 else
3079 {
3080 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3081 STAT(session_timeout);
3082 }
3083
3084 s_actions++;
3085 }
3086
3087 if (session[s].die)
3088 continue;
3089 }
3090
3091 if (sess_local[s].ipcp.restart <= time_now)
3092 {
3093 int next_state = session[s].ppp.ipcp;
3094 switch (session[s].ppp.ipcp)
3095 {
3096 case RequestSent:
3097 case AckReceived:
3098 next_state = RequestSent;
3099
3100 case AckSent:
3101 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
3102 {
3103 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
3104 sendipcp(s, session[s].tunnel);
3105 change_state(s, ipcp, next_state);
3106 }
3107 else
3108 {
3109 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3110 STAT(session_timeout);
3111 }
3112
3113 s_actions++;
3114 }
3115
3116 if (session[s].die)
3117 continue;
3118 }
3119
3120 if (sess_local[s].ipv6cp.restart <= time_now)
3121 {
3122 int next_state = session[s].ppp.ipv6cp;
3123 switch (session[s].ppp.ipv6cp)
3124 {
3125 case RequestSent:
3126 case AckReceived:
3127 next_state = RequestSent;
3128
3129 case AckSent:
3130 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
3131 {
3132 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
3133 sendipv6cp(s, session[s].tunnel);
3134 change_state(s, ipv6cp, next_state);
3135 }
3136 else
3137 {
3138 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
3139 change_state(s, ipv6cp, Stopped);
3140 }
3141
3142 s_actions++;
3143 }
3144 }
3145
3146 if (sess_local[s].ccp.restart <= time_now)
3147 {
3148 int next_state = session[s].ppp.ccp;
3149 switch (session[s].ppp.ccp)
3150 {
3151 case RequestSent:
3152 case AckReceived:
3153 next_state = RequestSent;
3154
3155 case AckSent:
3156 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
3157 {
3158 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
3159 sendccp(s, session[s].tunnel);
3160 change_state(s, ccp, next_state);
3161 }
3162 else
3163 {
3164 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
3165 change_state(s, ccp, Stopped);
3166 }
3167
3168 s_actions++;
3169 }
3170 }
3171
3172 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
3173 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
3174 {
3175 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3176 STAT(session_timeout);
3177 s_actions++;
3178 continue;
3179 }
3180
3181 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
3182 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
3183 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
3184 {
3185 uint8_t b[MAXETHER];
3186
3187 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
3188 if (!q) continue;
3189
3190 *q = EchoReq;
3191 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3192 *(uint16_t *)(q + 2) = htons(8); // Length
3193 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3194
3195 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3196 (int)(time_now - session[s].last_packet));
3197 tunnelsend(b, 24, session[s].tunnel); // send it
3198 sess_local[s].last_echo = time_now;
3199 s_actions++;
3200 }
3201
3202 // Drop sessions who have reached session_timeout seconds
3203 if (session[s].session_timeout && (time_now - session[s].opened >= session[s].session_timeout))
3204 {
3205 sessionshutdown(s, "Session Timeout Reached", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3206 STAT(session_timeout);
3207 s_actions++;
3208 continue;
3209 }
3210
3211 // Drop sessions who have reached idle_timeout seconds
3212 if (session[s].last_data && session[s].idle_timeout && (time_now - session[s].last_data >= session[s].idle_timeout))
3213 {
3214 sessionshutdown(s, "Idle Timeout Reached", CDN_ADMIN_DISC, TERM_IDLE_TIMEOUT);
3215 STAT(session_timeout);
3216 s_actions++;
3217 continue;
3218 }
3219
3220 // Check for actions requested from the CLI
3221 if ((a = cli_session_actions[s].action))
3222 {
3223 int send = 0;
3224
3225 cli_session_actions[s].action = 0;
3226 if (a & CLI_SESS_KILL)
3227 {
3228 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3229 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3230 a = 0; // dead, no need to check for other actions
3231 s_actions++;
3232 }
3233
3234 if (a & CLI_SESS_NOSNOOP)
3235 {
3236 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3237 session[s].snoop_ip = 0;
3238 session[s].snoop_port = 0;
3239 s_actions++;
3240 send++;
3241 }
3242 else if (a & CLI_SESS_SNOOP)
3243 {
3244 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%u)\n",
3245 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3246 cli_session_actions[s].snoop_port);
3247
3248 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3249 session[s].snoop_port = cli_session_actions[s].snoop_port;
3250 s_actions++;
3251 send++;
3252 }
3253
3254 if (a & CLI_SESS_NOTHROTTLE)
3255 {
3256 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3257 throttle_session(s, 0, 0);
3258 s_actions++;
3259 send++;
3260 }
3261 else if (a & CLI_SESS_THROTTLE)
3262 {
3263 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3264 cli_session_actions[s].throttle_in,
3265 cli_session_actions[s].throttle_out);
3266
3267 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3268 s_actions++;
3269 send++;
3270 }
3271
3272 if (a & CLI_SESS_NOFILTER)
3273 {
3274 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3275 filter_session(s, 0, 0);
3276 s_actions++;
3277 send++;
3278 }
3279 else if (a & CLI_SESS_FILTER)
3280 {
3281 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3282 cli_session_actions[s].filter_in,
3283 cli_session_actions[s].filter_out);
3284
3285 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3286 s_actions++;
3287 send++;
3288 }
3289
3290 if (send)
3291 cluster_send_session(s);
3292 }
3293
3294 // RADIUS interim accounting
3295 if (config->radius_accounting && config->radius_interim > 0
3296 && session[s].ip && !session[s].walled_garden
3297 && !sess_local[s].radius // RADIUS already in progress
3298 && time_now - sess_local[s].last_interim >= config->radius_interim)
3299 {
3300 int rad = radiusnew(s);
3301 if (!rad)
3302 {
3303 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3304 STAT(radius_overflow);
3305 continue;
3306 }
3307
3308 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3309 session[s].user, session[s].unique_id);
3310
3311 radiussend(rad, RADIUSINTERIM);
3312 sess_local[s].last_interim = time_now;
3313 s_actions++;
3314 }
3315 }
3316
3317 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3318 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3319 }
3320
3321 //
3322 // Are we in the middle of a tunnel update, or radius
3323 // requests??
3324 //
3325 static int still_busy(void)
3326 {
3327 int i;
3328 static clockt last_talked = 0;
3329 static clockt start_busy_wait = 0;
3330
3331 if (!config->cluster_iam_master)
3332 {
3333 #ifdef BGP
3334 static time_t stopped_bgp = 0;
3335 if (bgp_configured)
3336 {
3337 if (!stopped_bgp)
3338 {
3339 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3340
3341 for (i = 0; i < BGP_NUM_PEERS; i++)
3342 if (bgp_peers[i].state == Established)
3343 bgp_stop(&bgp_peers[i]);
3344
3345 stopped_bgp = time_now;
3346
3347 // we don't want to become master
3348 cluster_send_ping(0);
3349
3350 return 1;
3351 }
3352
3353 if (time_now < (stopped_bgp + QUIT_DELAY))
3354 return 1;
3355 }
3356 #endif /* BGP */
3357
3358 return 0;
3359 }
3360
3361 if (main_quit == QUIT_SHUTDOWN)
3362 {
3363 static int dropped = 0;
3364 if (!dropped)
3365 {
3366 int i;
3367
3368 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3369 for (i = 1; i < MAXTUNNEL; i++)
3370 if (tunnel[i].ip || tunnel[i].state)
3371 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3372
3373 dropped = 1;
3374 }
3375 }
3376
3377 if (start_busy_wait == 0)
3378 start_busy_wait = TIME;
3379
3380 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3381 {
3382 if (!tunnel[i].controlc)
3383 continue;
3384
3385 if (last_talked != TIME)
3386 {
3387 LOG(2, 0, 0, "Tunnel %u still has un-acked control messages.\n", i);
3388 last_talked = TIME;
3389 }
3390 return 1;
3391 }
3392
3393 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3394 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3395 {
3396 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3397 return 0;
3398 }
3399
3400 for (i = 1; i < MAXRADIUS; i++)
3401 {
3402 if (radius[i].state == RADIUSNULL)
3403 continue;
3404 if (radius[i].state == RADIUSWAIT)
3405 continue;
3406
3407 if (last_talked != TIME)
3408 {
3409 LOG(2, 0, 0, "Radius session %u is still busy (sid %u)\n", i, radius[i].session);
3410 last_talked = TIME;
3411 }
3412 return 1;
3413 }
3414
3415 return 0;
3416 }
3417
3418 #ifdef HAVE_EPOLL
3419 # include <sys/epoll.h>
3420 #else
3421 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3422 # include "fake_epoll.h"
3423 #endif
3424
3425 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3426 #define BASE_FDS 6
3427
3428 // additional polled fds
3429 #ifdef BGP
3430 # define EXTRA_FDS BGP_NUM_PEERS
3431 #else
3432 # define EXTRA_FDS 0
3433 #endif
3434
3435 // main loop - gets packets on tun or udp and processes them
3436 static void mainloop(void)
3437 {
3438 int i;
3439 uint8_t buf[65536];
3440 clockt next_cluster_ping = 0; // send initial ping immediately
3441 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3442 int maxevent = sizeof(events)/sizeof(*events);
3443
3444 if ((epollfd = epoll_create(maxevent)) < 0)
3445 {
3446 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3447 exit(1);
3448 }
3449
3450 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3451 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3452
3453 /* setup our fds to poll for input */
3454 {
3455 static struct event_data d[BASE_FDS];
3456 struct epoll_event e;
3457
3458 e.events = EPOLLIN;
3459 i = 0;
3460
3461 if (clifd >= 0)
3462 {
3463 d[i].type = FD_TYPE_CLI;
3464 e.data.ptr = &d[i++];
3465 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3466 }
3467
3468 d[i].type = FD_TYPE_CLUSTER;
3469 e.data.ptr = &d[i++];
3470 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3471
3472 d[i].type = FD_TYPE_TUN;
3473 e.data.ptr = &d[i++];
3474 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3475
3476 d[i].type = FD_TYPE_UDP;
3477 e.data.ptr = &d[i++];
3478 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3479
3480 d[i].type = FD_TYPE_CONTROL;
3481 e.data.ptr = &d[i++];
3482 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3483
3484 d[i].type = FD_TYPE_DAE;
3485 e.data.ptr = &d[i++];
3486 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3487 }
3488
3489 #ifdef BGP
3490 signal(SIGPIPE, SIG_IGN);
3491 bgp_setup(config->as_number);
3492 if (config->bind_address)
3493 bgp_add_route(config->bind_address, 0xffffffff);
3494
3495 for (i = 0; i < BGP_NUM_PEERS; i++)
3496 {
3497 if (config->neighbour[i].name[0])
3498 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3499 config->neighbour[i].as, config->neighbour[i].keepalive,
3500 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3501 }
3502 #endif /* BGP */
3503
3504 while (!main_quit || still_busy())
3505 {
3506 int more = 0;
3507 int n;
3508
3509
3510 if (main_reload)
3511 {
3512 main_reload = 0;
3513 read_config_file();
3514 config->reload_config++;
3515 }
3516
3517 if (config->reload_config)
3518 {
3519 config->reload_config = 0;
3520 update_config();
3521 }
3522
3523 #ifdef BGP
3524 bgp_set_poll();
3525 #endif /* BGP */
3526
3527 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3528 STAT(select_called);
3529
3530 TIME = now(NULL);
3531 if (n < 0)
3532 {
3533 if (errno == EINTR ||
3534 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3535 continue;
3536
3537 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3538 break; // exit
3539 }
3540
3541 if (n)
3542 {
3543 struct sockaddr_in addr;
3544 struct in_addr local;
3545 socklen_t alen;
3546 int c, s;
3547 int udp_ready = 0;
3548 int tun_ready = 0;
3549 int cluster_ready = 0;
3550 int udp_pkts = 0;
3551 int tun_pkts = 0;
3552 int cluster_pkts = 0;
3553 #ifdef BGP
3554 uint32_t bgp_events[BGP_NUM_PEERS];
3555 memset(bgp_events, 0, sizeof(bgp_events));
3556 #endif /* BGP */
3557
3558 for (c = n, i = 0; i < c; i++)
3559 {
3560 struct event_data *d = events[i].data.ptr;
3561
3562 switch (d->type)
3563 {
3564 case FD_TYPE_CLI: // CLI connections
3565 {
3566 int cli;
3567
3568 alen = sizeof(addr);
3569 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3570 {
3571 cli_do(cli);
3572 close(cli);
3573 }
3574 else
3575 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3576
3577 n--;
3578 break;
3579 }
3580
3581 // these are handled below, with multiple interleaved reads
3582 case FD_TYPE_CLUSTER: cluster_ready++; break;
3583 case FD_TYPE_TUN: tun_ready++; break;
3584 case FD_TYPE_UDP: udp_ready++; break;
3585
3586 case FD_TYPE_CONTROL: // nsctl commands
3587 alen = sizeof(addr);
3588 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3589 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3590 n--;
3591 break;
3592
3593 case FD_TYPE_DAE: // DAE requests
3594 alen = sizeof(addr);
3595 s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3596 if (s > 0) processdae(buf, s, &addr, alen, &local);
3597 n--;
3598 break;
3599
3600 case FD_TYPE_RADIUS: // RADIUS response
3601 alen = sizeof(addr);
3602 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3603 if (s >= 0 && config->cluster_iam_master)
3604 {
3605 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3606 addr.sin_addr.s_addr == config->radiusserver[1])
3607 processrad(buf, s, d->index);
3608 else
3609 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3610 fmtaddr(addr.sin_addr.s_addr, 0));
3611 }
3612
3613 n--;
3614 break;
3615
3616 #ifdef BGP
3617 case FD_TYPE_BGP:
3618 bgp_events[d->index] = events[i].events;
3619 n--;
3620 break;
3621 #endif /* BGP */
3622
3623 default:
3624 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3625 }
3626 }
3627
3628 #ifdef BGP
3629 bgp_process(bgp_events);
3630 #endif /* BGP */
3631
3632 for (c = 0; n && c < config->multi_read_count; c++)
3633 {
3634 // L2TP
3635 if (udp_ready)
3636 {
3637 alen = sizeof(addr);
3638 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3639 {
3640 processudp(buf, s, &addr);
3641 udp_pkts++;
3642 }
3643 else
3644 {
3645 udp_ready = 0;
3646 n--;
3647 }
3648 }
3649
3650 // incoming IP
3651 if (tun_ready)
3652 {
3653 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3654 {
3655 processtun(buf, s);
3656 tun_pkts++;
3657 }
3658 else
3659 {
3660 tun_ready = 0;
3661 n--;
3662 }
3663 }
3664
3665 // cluster
3666 if (cluster_ready)
3667 {
3668 alen = sizeof(addr);
3669 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3670 {
3671 processcluster(buf, s, addr.sin_addr.s_addr);
3672 cluster_pkts++;
3673 }
3674 else
3675 {
3676 cluster_ready = 0;
3677 n--;
3678 }
3679 }
3680 }
3681
3682 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3683 STAT(multi_read_used);
3684
3685 if (c >= config->multi_read_count)
3686 {
3687 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3688 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3689
3690 STAT(multi_read_exceeded);
3691 more++;
3692 }
3693 }
3694
3695 if (time_changed)
3696 {
3697 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3698
3699 // Log current traffic stats
3700 snprintf(config->bandwidth, sizeof(config->bandwidth),
3701 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3702 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3703 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3704 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3705
3706 udp_tx = udp_rx = 0;
3707 udp_rx_pkt = eth_rx_pkt = 0;
3708 eth_tx = eth_rx = 0;
3709 time_changed = 0;
3710
3711 if (config->dump_speed)
3712 printf("%s\n", config->bandwidth);
3713
3714 // Update the internal time counter
3715 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3716
3717 {
3718 // Run timer hooks
3719 struct param_timer p = { time_now };
3720 run_plugins(PLUGIN_TIMER, &p);
3721 }
3722 }
3723
3724 // Runs on every machine (master and slaves).
3725 if (next_cluster_ping <= TIME)
3726 {
3727 // Check to see which of the cluster is still alive..
3728
3729 cluster_send_ping(basetime); // Only does anything if we're a slave
3730 cluster_check_master(); // ditto.
3731
3732 cluster_heartbeat(); // Only does anything if we're a master.
3733 cluster_check_slaves(); // ditto.
3734
3735 master_update_counts(); // If we're a slave, send our byte counters to our master.
3736
3737 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3738 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3739 else
3740 next_cluster_ping = TIME + config->cluster_hb_interval;
3741 }
3742
3743 if (!config->cluster_iam_master)
3744 continue;
3745
3746 // Run token bucket filtering queue..
3747 // Only run it every 1/10th of a second.
3748 {
3749 static clockt last_run = 0;
3750 if (last_run != TIME)
3751 {
3752 last_run = TIME;
3753 tbf_run_timer();
3754 }
3755 }
3756
3757 // Handle timeouts, retries etc.
3758 {
3759 static double last_clean = 0;
3760 double this_clean;
3761 double diff;
3762
3763 TIME = now(&this_clean);
3764 diff = this_clean - last_clean;
3765
3766 // Run during idle time (after we've handled
3767 // all incoming packets) or every 1/10th sec
3768 if (!more || diff > 0.1)
3769 {
3770 regular_cleanups(diff);
3771 last_clean = this_clean;
3772 }
3773 }
3774
3775 if (*config->accounting_dir)
3776 {
3777 static clockt next_acct = 0;
3778 static clockt next_shut_acct = 0;
3779
3780 if (next_acct <= TIME)
3781 {
3782 // Dump accounting data
3783 next_acct = TIME + ACCT_TIME;
3784 next_shut_acct = TIME + ACCT_SHUT_TIME;
3785 dump_acct_info(1);
3786 }
3787 else if (next_shut_acct <= TIME)
3788 {
3789 // Dump accounting data for shutdown sessions
3790 next_shut_acct = TIME + ACCT_SHUT_TIME;
3791 if (shut_acct_n)
3792 dump_acct_info(0);
3793 }
3794 }
3795 }
3796
3797 // Are we the master and shutting down??
3798 if (config->cluster_iam_master)
3799 cluster_heartbeat(); // Flush any queued changes..
3800
3801 // Ok. Notify everyone we're shutting down. If we're
3802 // the master, this will force an election.
3803 cluster_send_ping(0);
3804
3805 //
3806 // Important!!! We MUST not process any packets past this point!
3807 LOG(1, 0, 0, "Shutdown complete\n");
3808 }
3809
3810 static void stripdomain(char *host)
3811 {
3812 char *p;
3813
3814 if ((p = strchr(host, '.')))
3815 {
3816 char *domain = 0;
3817 char _domain[1024];
3818
3819 // strip off domain
3820 FILE *resolv = fopen("/etc/resolv.conf", "r");
3821 if (resolv)
3822 {
3823 char buf[1024];
3824 char *b;
3825
3826 while (fgets(buf, sizeof(buf), resolv))
3827 {
3828 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3829 continue;
3830
3831 if (!isspace(buf[6]))
3832 continue;
3833
3834 b = buf + 7;
3835 while (isspace(*b)) b++;
3836
3837 if (*b)
3838 {
3839 char *d = b;
3840 while (*b && !isspace(*b)) b++;
3841 *b = 0;
3842 if (buf[0] == 'd') // domain is canonical
3843 {
3844 domain = d;
3845 break;
3846 }
3847
3848 // first search line
3849 if (!domain)
3850 {
3851 // hold, may be subsequent domain line
3852 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3853 domain = _domain;
3854 }
3855 }
3856 }
3857
3858 fclose(resolv);
3859 }
3860
3861 if (domain)
3862 {
3863 int hl = strlen(host);
3864 int dl = strlen(domain);
3865 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3866 host[hl -dl - 1] = 0;
3867 }
3868 else
3869 {
3870 *p = 0; // everything after first dot
3871 }
3872 }
3873 }
3874
3875 // Init data structures
3876 static void initdata(int optdebug, char *optconfig)
3877 {
3878 int i;
3879
3880 if (!(config = shared_malloc(sizeof(configt))))
3881 {
3882 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3883 exit(1);
3884 }
3885
3886 memset(config, 0, sizeof(configt));
3887 time(&config->start_time);
3888 strncpy(config->config_file, optconfig, strlen(optconfig));
3889 config->debug = optdebug;
3890 config->num_tbfs = MAXTBFS;
3891 config->rl_rate = 28; // 28kbps
3892 config->cluster_mcast_ttl = 1;
3893 config->cluster_master_min_adv = 1;
3894 config->ppp_restart_time = 3;
3895 config->ppp_max_configure = 10;
3896 config->ppp_max_failure = 5;
3897 strcpy(config->random_device, RANDOMDEVICE);
3898
3899 log_stream = stderr;
3900
3901 #ifdef RINGBUFFER
3902 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3903 {
3904 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3905 exit(1);
3906 }
3907 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3908 #endif
3909
3910 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3911 {
3912 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3913 exit(1);
3914 }
3915 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3916 {
3917 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3918 exit(1);
3919 }
3920 if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
3921 {
3922 LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
3923 exit(1);
3924 }
3925 if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
3926 {
3927 LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
3928 exit(1);
3929 }
3930 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3931 {
3932 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3933 exit(1);
3934 }
3935
3936 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3937 {
3938 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3939 exit(1);
3940 }
3941
3942 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3943 {
3944 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3945 exit(1);
3946 }
3947
3948 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3949 {
3950 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3951 exit(1);
3952 }
3953
3954 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3955 {
3956 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3957 exit(1);
3958 }
3959 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3960
3961 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3962 {
3963 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3964 exit(1);
3965 }
3966 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3967
3968 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3969 {
3970 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3971 exit(1);
3972 }
3973 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3974
3975 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3976 memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
3977 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3978 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3979 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3980
3981 // Put all the sessions on the free list marked as undefined.
3982 for (i = 1; i < MAXSESSION; i++)
3983 {
3984 session[i].next = i + 1;
3985 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3986 }
3987 session[MAXSESSION - 1].next = 0;
3988 sessionfree = 1;
3989
3990 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3991 for (i = 1; i < MAXTUNNEL; i++)
3992 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3993
3994 for (i = 1; i < MAXBUNDLE; i++) {
3995 bundle[i].state = BUNDLEUNDEF;
3996 }
3997
3998 if (!*hostname)
3999 {
4000 // Grab my hostname unless it's been specified
4001 gethostname(hostname, sizeof(hostname));
4002 stripdomain(hostname);
4003 }
4004
4005 _statistics->start_time = _statistics->last_reset = time(NULL);
4006
4007 #ifdef BGP
4008 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
4009 {
4010 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
4011 exit(1);
4012 }
4013 #endif /* BGP */
4014 }
4015
4016 static int assign_ip_address(sessionidt s)
4017 {
4018 uint32_t i;
4019 int best = -1;
4020 time_t best_time = time_now;
4021 char *u = session[s].user;
4022 char reuse = 0;
4023
4024
4025 CSTAT(assign_ip_address);
4026
4027 for (i = 1; i < ip_pool_size; i++)
4028 {
4029 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
4030 continue;
4031
4032 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
4033 {
4034 best = i;
4035 reuse = 1;
4036 break;
4037 }
4038
4039 if (ip_address_pool[i].last < best_time)
4040 {
4041 best = i;
4042 if (!(best_time = ip_address_pool[i].last))
4043 break; // never used, grab this one
4044 }
4045 }
4046
4047 if (best < 0)
4048 {
4049 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
4050 return 0;
4051 }
4052
4053 session[s].ip = ip_address_pool[best].address;
4054 session[s].ip_pool_index = best;
4055 ip_address_pool[best].assigned = 1;
4056 ip_address_pool[best].last = time_now;
4057 ip_address_pool[best].session = s;
4058 if (session[s].walled_garden)
4059 /* Don't track addresses of users in walled garden (note: this
4060 means that their address isn't "sticky" even if they get
4061 un-gardened). */
4062 ip_address_pool[best].user[0] = 0;
4063 else
4064 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
4065
4066 STAT(ip_allocated);
4067 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
4068 reuse ? "Reusing" : "Allocating", best);
4069
4070 return 1;
4071 }
4072
4073 static void free_ip_address(sessionidt s)
4074 {
4075 int i = session[s].ip_pool_index;
4076
4077
4078 CSTAT(free_ip_address);
4079
4080 if (!session[s].ip)
4081 return; // what the?
4082
4083 if (i < 0) // Is this actually part of the ip pool?
4084 i = 0;
4085
4086 STAT(ip_freed);
4087 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
4088 session[s].ip = 0;
4089 ip_address_pool[i].assigned = 0;
4090 ip_address_pool[i].session = 0;
4091 ip_address_pool[i].last = time_now;
4092 }
4093
4094 //
4095 // Fsck the address pool against the session table.
4096 // Normally only called when we become a master.
4097 //
4098 // This isn't perfect: We aren't keep tracking of which
4099 // users used to have an IP address.
4100 //
4101 void rebuild_address_pool(void)
4102 {
4103 int i;
4104
4105 //
4106 // Zero the IP pool allocation, and build
4107 // a map from IP address to pool index.
4108 for (i = 1; i < MAXIPPOOL; ++i)
4109 {
4110 ip_address_pool[i].assigned = 0;
4111 ip_address_pool[i].session = 0;
4112 if (!ip_address_pool[i].address)
4113 continue;
4114
4115 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
4116 }
4117
4118 for (i = 0; i < MAXSESSION; ++i)
4119 {
4120 int ipid;
4121 if (!(session[i].opened && session[i].ip))
4122 continue;
4123
4124 ipid = - lookup_ipmap(htonl(session[i].ip));
4125
4126 if (session[i].ip_pool_index < 0)
4127 {
4128 // Not allocated out of the pool.
4129 if (ipid < 1) // Not found in the pool either? good.
4130 continue;
4131
4132 LOG(0, i, 0, "Session %u has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
4133 i, fmtaddr(session[i].ip, 0), ipid);
4134
4135 // Fall through and process it as part of the pool.
4136 }
4137
4138
4139 if (ipid > MAXIPPOOL || ipid < 0)
4140 {
4141 LOG(0, i, 0, "Session %u has a pool IP that's not found in the pool! (%d)\n", i, ipid);
4142 ipid = -1;
4143 session[i].ip_pool_index = ipid;
4144 continue;
4145 }
4146
4147 ip_address_pool[ipid].assigned = 1;
4148 ip_address_pool[ipid].session = i;
4149 ip_address_pool[ipid].last = time_now;
4150 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
4151 session[i].ip_pool_index = ipid;
4152 cache_ipmap(session[i].ip, i); // Fix the ip map.
4153 }
4154 }
4155
4156 //
4157 // Fix the address pool to match a changed session.
4158 // (usually when the master sends us an update).
4159 static void fix_address_pool(int sid)
4160 {
4161 int ipid;
4162
4163 ipid = session[sid].ip_pool_index;
4164
4165 if (ipid > ip_pool_size)
4166 return; // Ignore it. rebuild_address_pool will fix it up.
4167
4168 if (ip_address_pool[ipid].address != session[sid].ip)
4169 return; // Just ignore it. rebuild_address_pool will take care of it.
4170
4171 ip_address_pool[ipid].assigned = 1;
4172 ip_address_pool[ipid].session = sid;
4173 ip_address_pool[ipid].last = time_now;
4174 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
4175 }
4176
4177 //
4178 // Add a block of addresses to the IP pool to hand out.
4179 //
4180 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
4181 {
4182 int i;
4183 if (mask == 0)
4184 mask = 0xffffffff; // Host route only.
4185
4186 addr &= mask;
4187
4188 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
4189 return ;
4190
4191 for (i = addr ;(i & mask) == addr; ++i)
4192 {
4193 if ((i & 0xff) == 0 || (i&0xff) == 255)
4194 continue; // Skip 0 and broadcast addresses.
4195
4196 ip_address_pool[ip_pool_size].address = i;
4197 ip_address_pool[ip_pool_size].assigned = 0;
4198 ++ip_pool_size;
4199 if (ip_pool_size >= MAXIPPOOL)
4200 {
4201 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
4202 return;
4203 }
4204 }
4205 }
4206
4207 // Initialize the IP address pool
4208 static void initippool()
4209 {
4210 FILE *f;
4211 char *p;
4212 char buf[4096];
4213 memset(ip_address_pool, 0, sizeof(ip_address_pool));
4214
4215 if (!(f = fopen(IPPOOLFILE, "r")))
4216 {
4217 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
4218 exit(1);
4219 }
4220
4221 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4222 {
4223 char *pool = buf;
4224 buf[4095] = 0; // Force it to be zero terminated/
4225
4226 if (*buf == '#' || *buf == '\n')
4227 continue; // Skip comments / blank lines
4228 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4229 if ((p = (char *)strchr(buf, ':')))
4230 {
4231 in_addr_t src;
4232 *p = '\0';
4233 src = inet_addr(buf);
4234 if (src == INADDR_NONE)
4235 {
4236 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4237 exit(1);
4238 }
4239 // This entry is for a specific IP only
4240 if (src != config->bind_address)
4241 continue;
4242 *p = ':';
4243 pool = p+1;
4244 }
4245 if ((p = (char *)strchr(pool, '/')))
4246 {
4247 // It's a range
4248 int numbits = 0;
4249 in_addr_t start = 0, mask = 0;
4250
4251 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4252 *p++ = 0;
4253 if (!*p || !(numbits = atoi(p)))
4254 {
4255 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4256 continue;
4257 }
4258 start = ntohl(inet_addr(pool));
4259 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
4260
4261 // Add a static route for this pool
4262 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
4263 fmtaddr(htonl(start), 0), 32 + mask);
4264
4265 routeset(0, start, mask, 0, 1);
4266
4267 add_to_ip_pool(start, mask);
4268 }
4269 else
4270 {
4271 // It's a single ip address
4272 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4273 }
4274 }
4275 fclose(f);
4276 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4277 }
4278
4279 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4280 {
4281 struct sockaddr_in snoop_addr = {0};
4282 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4283 return;
4284
4285 snoop_addr.sin_family = AF_INET;
4286 snoop_addr.sin_addr.s_addr = destination;
4287 snoop_addr.sin_port = ntohs(port);
4288
4289 LOG(5, 0, 0, "Snooping %d byte packet to %s:%u\n", size,
4290 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4291 htons(snoop_addr.sin_port));
4292
4293 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4294 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4295
4296 STAT(packets_snooped);
4297 }
4298
4299 static int dump_session(FILE **f, sessiont *s)
4300 {
4301 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4302 return 1;
4303
4304 if (!*f)
4305 {
4306 char filename[1024];
4307 char timestr[64];
4308 time_t now = time(NULL);
4309
4310 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4311 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4312
4313 if (!(*f = fopen(filename, "w")))
4314 {
4315 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4316 return 0;
4317 }
4318
4319 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4320 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4321 "# host: %s\n"
4322 "# endpoint: %s\n"
4323 "# time: %ld\n"
4324 "# uptime: %ld\n"
4325 "# format: username ip qos uptxoctets downrxoctets\n",
4326 hostname,
4327 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4328 now,
4329 now - basetime);
4330 }
4331
4332 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4333 fprintf(*f, "%s %s %d %u %u\n",
4334 s->user, // username
4335 fmtaddr(htonl(s->ip), 0), // ip
4336 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4337 (uint32_t) s->cin_delta, // uptxoctets
4338 (uint32_t) s->cout_delta); // downrxoctets
4339
4340 s->cin_delta = s->cout_delta = 0;
4341
4342 return 1;
4343 }
4344
4345 static void dump_acct_info(int all)
4346 {
4347 int i;
4348 FILE *f = NULL;
4349
4350
4351 CSTAT(dump_acct_info);
4352
4353 if (shut_acct_n)
4354 {
4355 for (i = 0; i < shut_acct_n; i++)
4356 dump_session(&f, &shut_acct[i]);
4357
4358 shut_acct_n = 0;
4359 }
4360
4361 if (all)
4362 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4363 dump_session(&f, &session[i]);
4364
4365 if (f)
4366 fclose(f);
4367 }
4368
4369 // Main program
4370 int main(int argc, char *argv[])
4371 {
4372 int i;
4373 int optdebug = 0;
4374 char *optconfig = CONFIGFILE;
4375
4376 time(&basetime); // start clock
4377
4378 // scan args
4379 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4380 {
4381 switch (i)
4382 {
4383 case 'd':
4384 if (fork()) exit(0);
4385 setsid();
4386 freopen("/dev/null", "r", stdin);
4387 freopen("/dev/null", "w", stdout);
4388 freopen("/dev/null", "w", stderr);
4389 break;
4390 case 'v':
4391 optdebug++;
4392 break;
4393 case 'c':
4394 optconfig = optarg;
4395 break;
4396 case 'h':
4397 snprintf(hostname, sizeof(hostname), "%s", optarg);
4398 break;
4399 default:
4400 printf("Args are:\n"
4401 "\t-d\t\tDetach from terminal\n"
4402 "\t-c <file>\tConfig file\n"
4403 "\t-h <hostname>\tForce hostname\n"
4404 "\t-v\t\tDebug\n");
4405
4406 return (0);
4407 break;
4408 }
4409 }
4410
4411 // Start the timer routine off
4412 time(&time_now);
4413 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4414
4415 initplugins();
4416 initdata(optdebug, optconfig);
4417
4418 init_cli(hostname);
4419 read_config_file();
4420 update_config();
4421 init_tbf(config->num_tbfs);
4422
4423 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4424 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering\n");
4425 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4426 {
4427 struct rlimit rlim;
4428 rlim.rlim_cur = RLIM_INFINITY;
4429 rlim.rlim_max = RLIM_INFINITY;
4430 // Remove the maximum core size
4431 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4432 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4433
4434 // Make core dumps go to /tmp
4435 chdir("/tmp");
4436 }
4437
4438 if (config->scheduler_fifo)
4439 {
4440 int ret;
4441 struct sched_param params = {0};
4442 params.sched_priority = 1;
4443
4444 if (get_nprocs() < 2)
4445 {
4446 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4447 config->scheduler_fifo = 0;
4448 }
4449 else
4450 {
4451 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4452 {
4453 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4454 }
4455 else
4456 {
4457 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4458 config->scheduler_fifo = 0;
4459 }
4460 }
4461 }
4462
4463 /* Set up the cluster communications port. */
4464 if (cluster_init() < 0)
4465 exit(1);
4466
4467 inittun();
4468 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4469
4470 initudp();
4471 initrad();
4472 initippool();
4473
4474 // seed prng
4475 {
4476 unsigned seed = time_now ^ getpid();
4477 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4478 srand(seed);
4479 }
4480
4481 signal(SIGHUP, sighup_handler);
4482 signal(SIGCHLD, sigchild_handler);
4483 signal(SIGTERM, shutdown_handler);
4484 signal(SIGINT, shutdown_handler);
4485 signal(SIGQUIT, shutdown_handler);
4486
4487 // Prevent us from getting paged out
4488 if (config->lock_pages)
4489 {
4490 if (!mlockall(MCL_CURRENT))
4491 LOG(1, 0, 0, "Locking pages into memory\n");
4492 else
4493 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4494 }
4495
4496 mainloop();
4497
4498 /* remove plugins (so cleanup code gets run) */
4499 plugins_done();
4500
4501 // Remove the PID file if we wrote it
4502 if (config->wrote_pid && *config->pid_file == '/')
4503 unlink(config->pid_file);
4504
4505 /* kill CLI children */
4506 signal(SIGTERM, SIG_IGN);
4507 kill(0, SIGTERM);
4508 return 0;
4509 }
4510
4511 static void sighup_handler(int sig)
4512 {
4513 main_reload++;
4514 }
4515
4516 static void shutdown_handler(int sig)
4517 {
4518 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4519 }
4520
4521 static void sigchild_handler(int sig)
4522 {
4523 while (waitpid(-1, NULL, WNOHANG) > 0)
4524 ;
4525 }
4526
4527 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4528 {
4529 MD5_CTX ctx;
4530 *challenge_response = NULL;
4531
4532 if (!*config->l2tp_secret)
4533 {
4534 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4535 return;
4536 }
4537
4538 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4539
4540 *challenge_response = calloc(17, 1);
4541
4542 MD5_Init(&ctx);
4543 MD5_Update(&ctx, &id, 1);
4544 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4545 MD5_Update(&ctx, challenge, challenge_length);
4546 MD5_Final(*challenge_response, &ctx);
4547
4548 return;
4549 }
4550
4551 static int facility_value(char *name)
4552 {
4553 int i;
4554 for (i = 0; facilitynames[i].c_name; i++)
4555 {
4556 if (strcmp(facilitynames[i].c_name, name) == 0)
4557 return facilitynames[i].c_val;
4558 }
4559 return 0;
4560 }
4561
4562 static void update_config()
4563 {
4564 int i;
4565 char *p;
4566 static int timeout = 0;
4567 static int interval = 0;
4568
4569 // Update logging
4570 closelog();
4571 syslog_log = 0;
4572 if (log_stream)
4573 {
4574 if (log_stream != stderr)
4575 fclose(log_stream);
4576
4577 log_stream = NULL;
4578 }
4579
4580 if (*config->log_filename)
4581 {
4582 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4583 {
4584 char *p = config->log_filename + 7;
4585 if (*p)
4586 {
4587 openlog("l2tpns", LOG_PID, facility_value(p));
4588 syslog_log = 1;
4589 }
4590 }
4591 else if (strchr(config->log_filename, '/') == config->log_filename)
4592 {
4593 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4594 {
4595 fseek(log_stream, 0, SEEK_END);
4596 setbuf(log_stream, NULL);
4597 }
4598 else
4599 {
4600 log_stream = stderr;
4601 setbuf(log_stream, NULL);
4602 }
4603 }
4604 }
4605 else
4606 {
4607 log_stream = stderr;
4608 setbuf(log_stream, NULL);
4609 }
4610
4611 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4612 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4613
4614 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4615 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4616 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4617
4618 // reset MRU/MSS globals
4619 MRU = config->l2tp_mtu - L2TP_HDRS;
4620 if (MRU > PPPoE_MRU)
4621 MRU = PPPoE_MRU;
4622
4623 MSS = MRU - TCP_HDRS;
4624
4625 // Update radius
4626 config->numradiusservers = 0;
4627 for (i = 0; i < MAXRADSERVER; i++)
4628 if (config->radiusserver[i])
4629 {
4630 config->numradiusservers++;
4631 // Set radius port: if not set, take the port from the
4632 // first radius server. For the first radius server,
4633 // take the #defined default value from l2tpns.h
4634
4635 // test twice, In case someone works with
4636 // a secondary radius server without defining
4637 // a primary one, this will work even then.
4638 if (i > 0 && !config->radiusport[i])
4639 config->radiusport[i] = config->radiusport[i-1];
4640 if (!config->radiusport[i])
4641 config->radiusport[i] = RADPORT;
4642 }
4643
4644 if (!config->numradiusservers)
4645 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4646
4647 // parse radius_authtypes_s
4648 config->radius_authtypes = config->radius_authprefer = 0;
4649 p = config->radius_authtypes_s;
4650 while (p && *p)
4651 {
4652 char *s = strpbrk(p, " \t,");
4653 int type = 0;
4654
4655 if (s)
4656 {
4657 *s++ = 0;
4658 while (*s == ' ' || *s == '\t')
4659 s++;
4660
4661 if (!*s)
4662 s = 0;
4663 }
4664
4665 if (!strncasecmp("chap", p, strlen(p)))
4666 type = AUTHCHAP;
4667 else if (!strncasecmp("pap", p, strlen(p)))
4668 type = AUTHPAP;
4669 else
4670 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4671
4672 config->radius_authtypes |= type;
4673 if (!config->radius_authprefer)
4674 config->radius_authprefer = type;
4675
4676 p = s;
4677 }
4678
4679 if (!config->radius_authtypes)
4680 {
4681 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4682 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4683 }
4684
4685 // normalise radius_authtypes_s
4686 if (config->radius_authprefer == AUTHPAP)
4687 {
4688 strcpy(config->radius_authtypes_s, "pap");
4689 if (config->radius_authtypes & AUTHCHAP)
4690 strcat(config->radius_authtypes_s, ", chap");
4691 }
4692 else
4693 {
4694 strcpy(config->radius_authtypes_s, "chap");
4695 if (config->radius_authtypes & AUTHPAP)
4696 strcat(config->radius_authtypes_s, ", pap");
4697 }
4698
4699 if (!config->radius_dae_port)
4700 config->radius_dae_port = DAEPORT;
4701
4702 // re-initialise the random number source
4703 initrandom(config->random_device);
4704
4705 // Update plugins
4706 for (i = 0; i < MAXPLUGINS; i++)
4707 {
4708 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4709 continue;
4710
4711 if (*config->plugins[i])
4712 {
4713 // Plugin added
4714 add_plugin(config->plugins[i]);
4715 }
4716 else if (*config->old_plugins[i])
4717 {
4718 // Plugin removed
4719 remove_plugin(config->old_plugins[i]);
4720 }
4721 }
4722
4723 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4724 if (!config->multi_read_count) config->multi_read_count = 10;
4725 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4726 if (!*config->cluster_interface)
4727 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4728
4729 if (!config->cluster_hb_interval)
4730 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4731
4732 if (!config->cluster_hb_timeout)
4733 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4734
4735 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4736 {
4737 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4738 // late, ensure we're sufficiently larger than that
4739 int t = 4 * config->cluster_hb_interval + 11;
4740
4741 if (config->cluster_hb_timeout < t)
4742 {
4743 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4744 config->cluster_hb_timeout = t;
4745 }
4746
4747 // Push timing changes to the slaves immediately if we're the master
4748 if (config->cluster_iam_master)
4749 cluster_heartbeat();
4750
4751 interval = config->cluster_hb_interval;
4752 timeout = config->cluster_hb_timeout;
4753 }
4754
4755 // Write PID file
4756 if (*config->pid_file == '/' && !config->wrote_pid)
4757 {
4758 FILE *f;
4759 if ((f = fopen(config->pid_file, "w")))
4760 {
4761 fprintf(f, "%d\n", getpid());
4762 fclose(f);
4763 config->wrote_pid = 1;
4764 }
4765 else
4766 {
4767 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4768 }
4769 }
4770 }
4771
4772 static void read_config_file()
4773 {
4774 FILE *f;
4775
4776 if (!config->config_file) return;
4777 if (!(f = fopen(config->config_file, "r")))
4778 {
4779 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4780 return;
4781 }
4782
4783 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4784 cli_do_file(f);
4785 LOG(3, 0, 0, "Done reading config file\n");
4786 fclose(f);
4787 }
4788
4789 int sessionsetup(sessionidt s, tunnelidt t)
4790 {
4791 // A session now exists, set it up
4792 in_addr_t ip;
4793 char *user;
4794 sessionidt i;
4795 int r;
4796
4797 CSTAT(sessionsetup);
4798
4799 LOG(3, s, t, "Doing session setup for session\n");
4800
4801 if (!session[s].ip)
4802 {
4803 assign_ip_address(s);
4804 if (!session[s].ip)
4805 {
4806 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4807 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
4808 return 0;
4809 }
4810 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4811 fmtaddr(htonl(session[s].ip), 0));
4812 }
4813
4814
4815 // Make sure this is right
4816 session[s].tunnel = t;
4817
4818 // Join a bundle if the MRRU option is accepted
4819 if (session[s].mrru > 0 && !session[s].bundle)
4820 {
4821 LOG(3, s, t, "This session can be part of multilink bundle\n");
4822 if (join_bundle(s))
4823 cluster_send_bundle(session[s].bundle);
4824 }
4825
4826 // zap old sessions with same IP and/or username
4827 // Don't kill gardened sessions - doing so leads to a DoS
4828 // from someone who doesn't need to know the password
4829 {
4830 ip = session[s].ip;
4831 user = session[s].user;
4832 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4833 {
4834 if (i == s) continue;
4835 if (!session[s].opened) continue;
4836 if (ip == session[i].ip)
4837 {
4838 sessionkill(i, "Duplicate IP address");
4839 continue;
4840 }
4841
4842 if (config->allow_duplicate_users)
4843 continue;
4844
4845 if (session[s].walled_garden || session[i].walled_garden)
4846 continue;
4847
4848 // Allow duplicate sessions for guest account.
4849 if (*config->guest_user && !strcasecmp(user, config->guest_user))
4850 continue;
4851
4852 // Allow duplicate sessions for multilink ones of the same bundle.
4853 if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle)
4854 continue;
4855
4856 // Drop the new session in case of duplicate sessionss, not the old one.
4857 if (!strcasecmp(user, session[i].user))
4858 sessionkill(i, "Duplicate session for users");
4859 }
4860 }
4861
4862 {
4863 int routed = 0;
4864
4865 // Add the route for this session.
4866 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4867 {
4868 if ((session[s].ip & session[s].route[r].mask) ==
4869 (session[s].route[r].ip & session[s].route[r].mask))
4870 routed++;
4871
4872 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4873 }
4874
4875 // Static IPs need to be routed if not already
4876 // convered by a Framed-Route. Anything else is part
4877 // of the IP address pool and is already routed, it
4878 // just needs to be added to the IP cache.
4879 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4880 if (session[s].ip_pool_index == -1) // static ip
4881 {
4882 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4883 }
4884 else
4885 cache_ipmap(session[s].ip, s);
4886 }
4887
4888 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4889 lcp_open(s, t); // transition to Network phase and send initial IPCP
4890
4891 // Run the plugin's against this new session.
4892 {
4893 struct param_new_session data = { &tunnel[t], &session[s] };
4894 run_plugins(PLUGIN_NEW_SESSION, &data);
4895 }
4896
4897 // Allocate TBFs if throttled
4898 if (session[s].throttle_in || session[s].throttle_out)
4899 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4900
4901 session[s].last_packet = session[s].last_data = time_now;
4902
4903 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4904 fmtaddr(htonl(session[s].ip), 0),
4905 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4906
4907 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4908
4909 return 1; // RADIUS OK and IP allocated, done...
4910 }
4911
4912 //
4913 // This session just got dropped on us by the master or something.
4914 // Make sure our tables up up to date...
4915 //
4916 int load_session(sessionidt s, sessiont *new)
4917 {
4918 int i;
4919 int newip = 0;
4920
4921 // Sanity checks.
4922 if (new->ip_pool_index >= MAXIPPOOL ||
4923 new->tunnel >= MAXTUNNEL)
4924 {
4925 LOG(0, s, 0, "Strange session update received!\n");
4926 // FIXME! What to do here?
4927 return 0;
4928 }
4929
4930 //
4931 // Ok. All sanity checks passed. Now we're committed to
4932 // loading the new session.
4933 //
4934
4935 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4936
4937 // See if routes/ip cache need updating
4938 if (new->ip != session[s].ip)
4939 newip++;
4940
4941 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4942 if (new->route[i].ip != session[s].route[i].ip ||
4943 new->route[i].mask != session[s].route[i].mask)
4944 newip++;
4945
4946 // needs update
4947 if (newip)
4948 {
4949 int routed = 0;
4950
4951 // remove old routes...
4952 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4953 {
4954 if ((session[s].ip & session[s].route[i].mask) ==
4955 (session[s].route[i].ip & session[s].route[i].mask))
4956 routed++;
4957
4958 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4959 }
4960
4961 // ...ip
4962 if (session[s].ip)
4963 {
4964 if (session[s].ip_pool_index == -1) // static IP
4965 {
4966 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4967 }
4968 else // It's part of the IP pool, remove it manually.
4969 uncache_ipmap(session[s].ip);
4970 }
4971
4972 routed = 0;
4973
4974 // add new routes...
4975 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4976 {
4977 if ((new->ip & new->route[i].mask) ==
4978 (new->route[i].ip & new->route[i].mask))
4979 routed++;
4980
4981 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4982 }
4983
4984 // ...ip
4985 if (new->ip)
4986 {
4987 // If there's a new one, add it.
4988 if (new->ip_pool_index == -1)
4989 {
4990 if (!routed) routeset(s, new->ip, 0, 0, 1);
4991 }
4992 else
4993 cache_ipmap(new->ip, s);
4994 }
4995 }
4996
4997 // check v6 routing
4998 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4999 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
5000
5001 // check filters
5002 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
5003 {
5004 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %u\n", (int) new->filter_in);
5005 new->filter_in = 0;
5006 }
5007
5008 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
5009 {
5010 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %u\n", (int) new->filter_out);
5011 new->filter_out = 0;
5012 }
5013
5014 if (new->filter_in != session[s].filter_in)
5015 {
5016 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
5017 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
5018 }
5019
5020 if (new->filter_out != session[s].filter_out)
5021 {
5022 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
5023 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
5024 }
5025
5026 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
5027 // for walking the sessions to forward byte counts to the master.
5028 config->cluster_highest_sessionid = s;
5029
5030 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
5031
5032 // Do fixups into address pool.
5033 if (new->ip_pool_index != -1)
5034 fix_address_pool(s);
5035
5036 return 1;
5037 }
5038
5039 static void initplugins()
5040 {
5041 int i;
5042
5043 loaded_plugins = ll_init();
5044 // Initialize the plugins to nothing
5045 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
5046 plugins[i] = ll_init();
5047 }
5048
5049 static void *open_plugin(char *plugin_name, int load)
5050 {
5051 char path[256] = "";
5052
5053 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
5054 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
5055 return dlopen(path, RTLD_NOW);
5056 }
5057
5058 // plugin callback to get a config value
5059 static void *getconfig(char *key, enum config_typet type)
5060 {
5061 int i;
5062
5063 for (i = 0; config_values[i].key; i++)
5064 {
5065 if (!strcmp(config_values[i].key, key))
5066 {
5067 if (config_values[i].type == type)
5068 return ((void *) config) + config_values[i].offset;
5069
5070 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
5071 key, type, config_values[i].type);
5072
5073 return 0;
5074 }
5075 }
5076
5077 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
5078 return 0;
5079 }
5080
5081 static int add_plugin(char *plugin_name)
5082 {
5083 static struct pluginfuncs funcs = {
5084 _log,
5085 _log_hex,
5086 fmtaddr,
5087 sessionbyuser,
5088 sessiontbysessionidt,
5089 sessionidtbysessiont,
5090 radiusnew,
5091 radiussend,
5092 getconfig,
5093 sessionshutdown,
5094 sessionkill,
5095 throttle_session,
5096 cluster_send_session,
5097 };
5098
5099 void *p = open_plugin(plugin_name, 1);
5100 int (*initfunc)(struct pluginfuncs *);
5101 int i;
5102
5103 if (!p)
5104 {
5105 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
5106 return -1;
5107 }
5108
5109 if (ll_contains(loaded_plugins, p))
5110 {
5111 dlclose(p);
5112 return 0; // already loaded
5113 }
5114
5115 {
5116 int *v = dlsym(p, "plugin_api_version");
5117 if (!v || *v != PLUGIN_API_VERSION)
5118 {
5119 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
5120 dlclose(p);
5121 return -1;
5122 }
5123 }
5124
5125 if ((initfunc = dlsym(p, "plugin_init")))
5126 {
5127 if (!initfunc(&funcs))
5128 {
5129 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
5130 dlclose(p);
5131 return -1;
5132 }
5133 }
5134
5135 ll_push(loaded_plugins, p);
5136
5137 for (i = 0; i < max_plugin_functions; i++)
5138 {
5139 void *x;
5140 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5141 {
5142 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
5143 ll_push(plugins[i], x);
5144 }
5145 }
5146
5147 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
5148 return 1;
5149 }
5150
5151 static void run_plugin_done(void *plugin)
5152 {
5153 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
5154
5155 if (donefunc)
5156 donefunc();
5157 }
5158
5159 static int remove_plugin(char *plugin_name)
5160 {
5161 void *p = open_plugin(plugin_name, 0);
5162 int loaded = 0;
5163
5164 if (!p)
5165 return -1;
5166
5167 if (ll_contains(loaded_plugins, p))
5168 {
5169 int i;
5170 for (i = 0; i < max_plugin_functions; i++)
5171 {
5172 void *x;
5173 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5174 ll_delete(plugins[i], x);
5175 }
5176
5177 ll_delete(loaded_plugins, p);
5178 run_plugin_done(p);
5179 loaded = 1;
5180 }
5181
5182 dlclose(p);
5183 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
5184 return loaded;
5185 }
5186
5187 int run_plugins(int plugin_type, void *data)
5188 {
5189 int (*func)(void *data);
5190
5191 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
5192 return PLUGIN_RET_ERROR;
5193
5194 ll_reset(plugins[plugin_type]);
5195 while ((func = ll_next(plugins[plugin_type])))
5196 {
5197 int r = func(data);
5198
5199 if (r != PLUGIN_RET_OK)
5200 return r; // stop here
5201 }
5202
5203 return PLUGIN_RET_OK;
5204 }
5205
5206 static void plugins_done()
5207 {
5208 void *p;
5209
5210 ll_reset(loaded_plugins);
5211 while ((p = ll_next(loaded_plugins)))
5212 run_plugin_done(p);
5213 }
5214
5215 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
5216 {
5217 struct nsctl request;
5218 struct nsctl response;
5219 int type = unpack_control(&request, buf, len);
5220 int r;
5221 void *p;
5222
5223 if (log_stream && config->debug >= 4)
5224 {
5225 if (type < 0)
5226 {
5227 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
5228 fmtaddr(addr->sin_addr.s_addr, 0), type);
5229 }
5230 else
5231 {
5232 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5233 dump_control(&request, log_stream);
5234 }
5235 }
5236
5237 switch (type)
5238 {
5239 case NSCTL_REQ_LOAD:
5240 if (request.argc != 1)
5241 {
5242 response.type = NSCTL_RES_ERR;
5243 response.argc = 1;
5244 response.argv[0] = "name of plugin required";
5245 }
5246 else if ((r = add_plugin(request.argv[0])) < 1)
5247 {
5248 response.type = NSCTL_RES_ERR;
5249 response.argc = 1;
5250 response.argv[0] = !r
5251 ? "plugin already loaded"
5252 : "error loading plugin";
5253 }
5254 else
5255 {
5256 response.type = NSCTL_RES_OK;
5257 response.argc = 0;
5258 }
5259
5260 break;
5261
5262 case NSCTL_REQ_UNLOAD:
5263 if (request.argc != 1)
5264 {
5265 response.type = NSCTL_RES_ERR;
5266 response.argc = 1;
5267 response.argv[0] = "name of plugin required";
5268 }
5269 else if ((r = remove_plugin(request.argv[0])) < 1)
5270 {
5271 response.type = NSCTL_RES_ERR;
5272 response.argc = 1;
5273 response.argv[0] = !r
5274 ? "plugin not loaded"
5275 : "plugin not found";
5276 }
5277 else
5278 {
5279 response.type = NSCTL_RES_OK;
5280 response.argc = 0;
5281 }
5282
5283 break;
5284
5285 case NSCTL_REQ_HELP:
5286 response.type = NSCTL_RES_OK;
5287 response.argc = 0;
5288
5289 ll_reset(loaded_plugins);
5290 while ((p = ll_next(loaded_plugins)))
5291 {
5292 char **help = dlsym(p, "plugin_control_help");
5293 while (response.argc < 0xff && help && *help)
5294 response.argv[response.argc++] = *help++;
5295 }
5296
5297 break;
5298
5299 case NSCTL_REQ_CONTROL:
5300 {
5301 struct param_control param = {
5302 config->cluster_iam_master,
5303 request.argc,
5304 request.argv,
5305 0,
5306 NULL,
5307 };
5308
5309 int r = run_plugins(PLUGIN_CONTROL, &param);
5310
5311 if (r == PLUGIN_RET_ERROR)
5312 {
5313 response.type = NSCTL_RES_ERR;
5314 response.argc = 1;
5315 response.argv[0] = param.additional
5316 ? param.additional
5317 : "error returned by plugin";
5318 }
5319 else if (r == PLUGIN_RET_NOTMASTER)
5320 {
5321 static char msg[] = "must be run on master: 000.000.000.000";
5322
5323 response.type = NSCTL_RES_ERR;
5324 response.argc = 1;
5325 if (config->cluster_master_address)
5326 {
5327 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5328 response.argv[0] = msg;
5329 }
5330 else
5331 {
5332 response.argv[0] = "must be run on master: none elected";
5333 }
5334 }
5335 else if (!(param.response & NSCTL_RESPONSE))
5336 {
5337 response.type = NSCTL_RES_ERR;
5338 response.argc = 1;
5339 response.argv[0] = param.response
5340 ? "unrecognised response value from plugin"
5341 : "unhandled action";
5342 }
5343 else
5344 {
5345 response.type = param.response;
5346 response.argc = 0;
5347 if (param.additional)
5348 {
5349 response.argc = 1;
5350 response.argv[0] = param.additional;
5351 }
5352 }
5353 }
5354
5355 break;
5356
5357 default:
5358 response.type = NSCTL_RES_ERR;
5359 response.argc = 1;
5360 response.argv[0] = "error unpacking control packet";
5361 }
5362
5363 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5364 if (!buf)
5365 {
5366 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5367 return;
5368 }
5369
5370 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5371 if (r > 0)
5372 {
5373 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5374 if (log_stream && config->debug >= 4)
5375 {
5376 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5377 dump_control(&response, log_stream);
5378 }
5379 }
5380 else
5381 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5382 fmtaddr(addr->sin_addr.s_addr, 0), r);
5383
5384 free(buf);
5385 }
5386
5387 static tunnelidt new_tunnel()
5388 {
5389 tunnelidt i;
5390 for (i = 1; i < MAXTUNNEL; i++)
5391 {
5392 if (tunnel[i].state == TUNNELFREE)
5393 {
5394 LOG(4, 0, i, "Assigning tunnel ID %u\n", i);
5395 if (i > config->cluster_highest_tunnelid)
5396 config->cluster_highest_tunnelid = i;
5397 return i;
5398 }
5399 }
5400 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5401 return 0;
5402 }
5403
5404 //
5405 // We're becoming the master. Do any required setup..
5406 //
5407 // This is principally telling all the plugins that we're
5408 // now a master, and telling them about all the sessions
5409 // that are active too..
5410 //
5411 void become_master(void)
5412 {
5413 int s, i;
5414 static struct event_data d[RADIUS_FDS];
5415 struct epoll_event e;
5416
5417 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5418
5419 // running a bunch of iptables commands is slow and can cause
5420 // the master to drop tunnels on takeover--kludge around the
5421 // problem by forking for the moment (note: race)
5422 if (!fork_and_close())
5423 {
5424 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5425 {
5426 if (!session[s].opened) // Not an in-use session.
5427 continue;
5428
5429 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5430 }
5431 exit(0);
5432 }
5433
5434 // add radius fds
5435 e.events = EPOLLIN;
5436 for (i = 0; i < RADIUS_FDS; i++)
5437 {
5438 d[i].type = FD_TYPE_RADIUS;
5439 d[i].index = i;
5440 e.data.ptr = &d[i];
5441
5442 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5443 }
5444 }
5445
5446 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5447 {
5448 int s, i;
5449 int count = 0;
5450 int buckets[64];
5451
5452 if (CLI_HELP_REQUESTED)
5453 return CLI_HELP_NO_ARGS;
5454
5455 time(&time_now);
5456 for (i = 0; i < 64;++i) buckets[i] = 0;
5457
5458 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5459 {
5460 int idle;
5461 if (!session[s].opened)
5462 continue;
5463
5464 idle = time_now - session[s].last_data;
5465 idle /= 5 ; // In multiples of 5 seconds.
5466 if (idle < 0)
5467 idle = 0;
5468 if (idle > 63)
5469 idle = 63;
5470
5471 ++count;
5472 ++buckets[idle];
5473 }
5474
5475 for (i = 0; i < 63; ++i)
5476 {
5477 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5478 }
5479 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5480 cli_print(cli, "%d total sessions open.", count);
5481 return CLI_OK;
5482 }
5483
5484 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5485 {
5486 int s, i;
5487 int count = 0;
5488 int buckets[64];
5489
5490 if (CLI_HELP_REQUESTED)
5491 return CLI_HELP_NO_ARGS;
5492
5493 time(&time_now);
5494 for (i = 0; i < 64;++i) buckets[i] = 0;
5495
5496 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5497 {
5498 int open = 0, d;
5499 if (!session[s].opened)
5500 continue;
5501
5502 d = time_now - session[s].opened;
5503 if (d < 0)
5504 d = 0;
5505 while (d > 1 && open < 32)
5506 {
5507 ++open;
5508 d >>= 1; // half.
5509 }
5510 ++count;
5511 ++buckets[open];
5512 }
5513
5514 s = 1;
5515 for (i = 0; i < 30; ++i)
5516 {
5517 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5518 s <<= 1;
5519 }
5520 cli_print(cli, "%d total sessions open.", count);
5521 return CLI_OK;
5522 }
5523
5524 /* Unhide an avp.
5525 *
5526 * This unencodes the AVP using the L2TP secret and the previously
5527 * stored random vector. It overwrites the hidden data with the
5528 * unhidden AVP subformat.
5529 */
5530 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5531 {
5532 MD5_CTX ctx;
5533 uint8_t digest[16];
5534 uint8_t *last;
5535 size_t d = 0;
5536 uint16_t m = htons(type);
5537
5538 // Compute initial pad
5539 MD5_Init(&ctx);
5540 MD5_Update(&ctx, (unsigned char *) &m, 2);
5541 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5542 MD5_Update(&ctx, vector, vec_len);
5543 MD5_Final(digest, &ctx);
5544
5545 // pointer to last decoded 16 octets
5546 last = value;
5547
5548 while (len > 0)
5549 {
5550 // calculate a new pad based on the last decoded block
5551 if (d >= sizeof(digest))
5552 {
5553 MD5_Init(&ctx);
5554 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5555 MD5_Update(&ctx, last, sizeof(digest));
5556 MD5_Final(digest, &ctx);
5557
5558 d = 0;
5559 last = value;
5560 }
5561
5562 *value++ ^= digest[d++];
5563 len--;
5564 }
5565 }
5566
5567 int find_filter(char const *name, size_t len)
5568 {
5569 int free = -1;
5570 int i;
5571
5572 for (i = 0; i < MAXFILTER; i++)
5573 {
5574 if (!*ip_filters[i].name)
5575 {
5576 if (free < 0)
5577 free = i;
5578
5579 continue;
5580 }
5581
5582 if (strlen(ip_filters[i].name) != len)
5583 continue;
5584
5585 if (!strncmp(ip_filters[i].name, name, len))
5586 return i;
5587 }
5588
5589 return free;
5590 }
5591
5592 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5593 {
5594 switch (p->op)
5595 {
5596 case FILTER_PORT_OP_EQ: return port == p->port;
5597 case FILTER_PORT_OP_NEQ: return port != p->port;
5598 case FILTER_PORT_OP_GT: return port > p->port;
5599 case FILTER_PORT_OP_LT: return port < p->port;
5600 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5601 }
5602
5603 return 0;
5604 }
5605
5606 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5607 {
5608 switch (op)
5609 {
5610 case FILTER_FLAG_OP_ANY:
5611 return (flags & sflags) || (~flags & cflags);
5612
5613 case FILTER_FLAG_OP_ALL:
5614 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5615
5616 case FILTER_FLAG_OP_EST:
5617 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5618 }
5619
5620 return 0;
5621 }
5622
5623 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5624 {
5625 uint16_t frag_offset;
5626 uint8_t proto;
5627 in_addr_t src_ip;
5628 in_addr_t dst_ip;
5629 uint16_t src_port = 0;
5630 uint16_t dst_port = 0;
5631 uint8_t flags = 0;
5632 ip_filter_rulet *rule;
5633
5634 if (len < 20) // up to end of destination address
5635 return 0;
5636
5637 if ((*buf >> 4) != 4) // IPv4
5638 return 0;
5639
5640 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5641 proto = buf[9];
5642 src_ip = *(in_addr_t *) (buf + 12);
5643 dst_ip = *(in_addr_t *) (buf + 16);
5644
5645 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5646 {
5647 int l = (buf[0] & 0xf) * 4; // length of IP header
5648 if (len < l + 4) // ports
5649 return 0;
5650
5651 src_port = ntohs(*(uint16_t *) (buf + l));
5652 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5653 if (proto == IPPROTO_TCP)
5654 {
5655 if (len < l + 14) // flags
5656 return 0;
5657
5658 flags = buf[l + 13] & 0x3f;
5659 }
5660 }
5661
5662 for (rule = ip_filters[filter].rules; rule->action; rule++)
5663 {
5664 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5665 continue;
5666
5667 if (rule->src_wild != INADDR_BROADCAST &&
5668 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5669 continue;
5670
5671 if (rule->dst_wild != INADDR_BROADCAST &&
5672 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5673 continue;
5674
5675 if (frag_offset)
5676 {
5677 // layer 4 deny rules are skipped
5678 if (rule->action == FILTER_ACTION_DENY &&
5679 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5680 continue;
5681 }
5682 else
5683 {
5684 if (rule->frag)
5685 continue;
5686
5687 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5688 {
5689 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5690 continue;
5691
5692 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5693 continue;
5694
5695 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5696 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5697 continue;
5698 }
5699 }
5700
5701 // matched
5702 rule->counter++;
5703 return rule->action == FILTER_ACTION_PERMIT;
5704 }
5705
5706 // default deny
5707 return 0;
5708 }