b37395592c94d815749712f4ee877a5df2933e69
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.163 2006-04-27 09:53:49 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("setuid", target_uid, INT),
138 CONFIG("dump_speed", dump_speed, BOOL),
139 CONFIG("multi_read_count", multi_read_count, INT),
140 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
141 CONFIG("lock_pages", lock_pages, BOOL),
142 CONFIG("icmp_rate", icmp_rate, INT),
143 CONFIG("packet_limit", max_packets, INT),
144 CONFIG("cluster_address", cluster_address, IPv4),
145 CONFIG("cluster_interface", cluster_interface, STRING),
146 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
147 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
148 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
149 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
150 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
151 { NULL, 0, 0, 0 },
152 };
153
154 static char *plugin_functions[] = {
155 NULL,
156 "plugin_pre_auth",
157 "plugin_post_auth",
158 "plugin_packet_rx",
159 "plugin_packet_tx",
160 "plugin_timer",
161 "plugin_new_session",
162 "plugin_kill_session",
163 "plugin_control",
164 "plugin_radius_response",
165 "plugin_radius_reset",
166 "plugin_radius_account",
167 "plugin_become_master",
168 "plugin_new_session_master",
169 };
170
171 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
172
173 // Counters for shutdown sessions
174 static sessiont shut_acct[8192];
175 static sessionidt shut_acct_n = 0;
176
177 tunnelt *tunnel = NULL; // Array of tunnel structures.
178 bundlet *bundle = NULL; // Array of bundle structures.
179 fragmentationt *frag = NULL; // Array of fragmentation structures.
180 sessiont *session = NULL; // Array of session structures.
181 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
182 radiust *radius = NULL; // Array of radius structures.
183 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
184 ip_filtert *ip_filters = NULL; // Array of named filters.
185 static controlt *controlfree = 0;
186 struct Tstats *_statistics = NULL;
187 #ifdef RINGBUFFER
188 struct Tringbuffer *ringbuffer = NULL;
189 #endif
190
191 static void cache_ipmap(in_addr_t ip, int s);
192 static void uncache_ipmap(in_addr_t ip);
193 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
194 static void free_ip_address(sessionidt s);
195 static void dump_acct_info(int all);
196 static void sighup_handler(int sig);
197 static void shutdown_handler(int sig);
198 static void sigchild_handler(int sig);
199 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
200 static void update_config(void);
201 static void read_config_file(void);
202 static void initplugins(void);
203 static int add_plugin(char *plugin_name);
204 static int remove_plugin(char *plugin_name);
205 static void plugins_done(void);
206 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
207 static tunnelidt new_tunnel(void);
208 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
209 static void bundleclear(bundleidt b);
210
211 // on slaves, alow BGP to withdraw cleanly before exiting
212 #define QUIT_DELAY 5
213
214 // quit actions (master)
215 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
216 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
217
218 // return internal time (10ths since process startup), set f if given
219 // as a side-effect sets time_now, and time_changed
220 static clockt now(double *f)
221 {
222 struct timeval t;
223 gettimeofday(&t, 0);
224 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
225 if (t.tv_sec != time_now)
226 {
227 time_now = t.tv_sec;
228 time_changed++;
229 }
230 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
231 }
232
233 // work out a retry time based on try number
234 // This is a straight bounded exponential backoff.
235 // Maximum re-try time is 32 seconds. (2^5).
236 clockt backoff(uint8_t try)
237 {
238 if (try > 5) try = 5; // max backoff
239 return now(NULL) + 10 * (1 << try);
240 }
241
242
243 //
244 // Log a debug message. Typically called via the LOG macro
245 //
246 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
247 {
248 static char message[65536] = {0};
249 va_list ap;
250
251 #ifdef RINGBUFFER
252 if (ringbuffer)
253 {
254 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
255 ringbuffer->tail = 0;
256 if (ringbuffer->tail == ringbuffer->head)
257 if (++ringbuffer->head >= RINGBUFFER_SIZE)
258 ringbuffer->head = 0;
259
260 ringbuffer->buffer[ringbuffer->tail].level = level;
261 ringbuffer->buffer[ringbuffer->tail].session = s;
262 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
263 va_start(ap, format);
264 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
265 va_end(ap);
266 }
267 #endif
268
269 if (config->debug < level) return;
270
271 va_start(ap, format);
272 vsnprintf(message, sizeof(message), format, ap);
273
274 if (log_stream)
275 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
276 else if (syslog_log)
277 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
278
279 va_end(ap);
280 }
281
282 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
283 {
284 int i, j;
285 const uint8_t *d = data;
286
287 if (config->debug < level) return;
288
289 // No support for _log_hex to syslog
290 if (log_stream)
291 {
292 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
293 setvbuf(log_stream, NULL, _IOFBF, 16384);
294
295 for (i = 0; i < maxsize; )
296 {
297 fprintf(log_stream, "%4X: ", i);
298 for (j = i; j < maxsize && j < (i + 16); j++)
299 {
300 fprintf(log_stream, "%02X ", d[j]);
301 if (j == i + 7)
302 fputs(": ", log_stream);
303 }
304
305 for (; j < i + 16; j++)
306 {
307 fputs(" ", log_stream);
308 if (j == i + 7)
309 fputs(": ", log_stream);
310 }
311
312 fputs(" ", log_stream);
313 for (j = i; j < maxsize && j < (i + 16); j++)
314 {
315 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
316 fputc(d[j], log_stream);
317 else
318 fputc('.', log_stream);
319
320 if (j == i + 7)
321 fputs(" ", log_stream);
322 }
323
324 i = j;
325 fputs("\n", log_stream);
326 }
327
328 fflush(log_stream);
329 setbuf(log_stream, NULL);
330 }
331 }
332
333 // update a counter, accumulating 2^32 wraps
334 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
335 {
336 uint32_t new = *counter + delta;
337 if (new < *counter)
338 (*wrap)++;
339
340 *counter = new;
341 }
342
343 // initialise the random generator
344 static void initrandom(char *source)
345 {
346 static char path[sizeof(config->random_device)] = "*undefined*";
347
348 // reinitialise only if we are forced to do so or if the config has changed
349 if (source && !strncmp(path, source, sizeof(path)))
350 return;
351
352 // close previous source, if any
353 if (rand_fd >= 0)
354 close(rand_fd);
355
356 rand_fd = -1;
357
358 if (source)
359 {
360 // register changes
361 snprintf(path, sizeof(path), "%s", source);
362
363 if (*path == '/')
364 {
365 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
366 if (rand_fd < 0)
367 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
368 path, strerror(errno));
369 }
370 }
371 }
372
373 // fill buffer with random data
374 void random_data(uint8_t *buf, int len)
375 {
376 int n = 0;
377
378 CSTAT(random_data);
379 if (rand_fd >= 0)
380 {
381 n = read(rand_fd, buf, len);
382 if (n >= len) return;
383 if (n < 0)
384 {
385 if (errno != EAGAIN)
386 {
387 LOG(0, 0, 0, "Error reading from random source: %s\n",
388 strerror(errno));
389
390 // fall back to rand()
391 initrandom(NULL);
392 }
393
394 n = 0;
395 }
396 }
397
398 // append missing data
399 while (n < len)
400 // not using the low order bits from the prng stream
401 buf[n++] = (rand() >> 4) & 0xff;
402 }
403
404 // Add a route
405 //
406 // This adds it to the routing table, advertises it
407 // via BGP if enabled, and stuffs it into the
408 // 'sessionbyip' cache.
409 //
410 // 'ip' and 'mask' must be in _host_ order.
411 //
412 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
413 {
414 struct rtentry r;
415 int i;
416
417 if (!mask) mask = 0xffffffff;
418
419 ip &= mask; // Force the ip to be the first one in the route.
420
421 memset(&r, 0, sizeof(r));
422 r.rt_dev = config->tundevice;
423 r.rt_dst.sa_family = AF_INET;
424 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
425 r.rt_gateway.sa_family = AF_INET;
426 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
427 r.rt_genmask.sa_family = AF_INET;
428 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
429 r.rt_flags = (RTF_UP | RTF_STATIC);
430 if (gw)
431 r.rt_flags |= RTF_GATEWAY;
432 else if (mask == 0xffffffff)
433 r.rt_flags |= RTF_HOST;
434
435 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
436 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
437 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
438
439 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
440 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
441
442 #ifdef BGP
443 if (add)
444 bgp_add_route(htonl(ip), htonl(mask));
445 else
446 bgp_del_route(htonl(ip), htonl(mask));
447 #endif /* BGP */
448
449 // Add/Remove the IPs to the 'sessionbyip' cache.
450 // Note that we add the zero address in the case of
451 // a network route. Roll on CIDR.
452
453 // Note that 's == 0' implies this is the address pool.
454 // We still cache it here, because it will pre-fill
455 // the malloc'ed tree.
456
457 if (s)
458 {
459 if (!add) // Are we deleting a route?
460 s = 0; // Caching the session as '0' is the same as uncaching.
461
462 for (i = ip; (i&mask) == (ip&mask) ; ++i)
463 cache_ipmap(i, s);
464 }
465 }
466
467 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
468 {
469 struct in6_rtmsg rt;
470 char ipv6addr[INET6_ADDRSTRLEN];
471
472 if (ifr6fd < 0)
473 {
474 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
475 return;
476 }
477
478 memset(&rt, 0, sizeof(rt));
479
480 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
481 rt.rtmsg_dst_len = prefixlen;
482 rt.rtmsg_metric = 1;
483 rt.rtmsg_flags = RTF_UP;
484 rt.rtmsg_ifindex = tunidx;
485
486 LOG(1, 0, 0, "Route %s %s/%d\n",
487 add ? "add" : "del",
488 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
489 prefixlen);
490
491 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
492 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
493 strerror(errno));
494
495 // FIXME: need to add BGP routing (RFC2858)
496
497 if (s)
498 {
499 if (!add) // Are we deleting a route?
500 s = 0; // Caching the session as '0' is the same as uncaching.
501
502 cache_ipv6map(ip, prefixlen, s);
503 }
504
505 return;
506 }
507
508 // defined in linux/ipv6.h, but tricky to include from user-space
509 // TODO: move routing to use netlink rather than ioctl
510 struct in6_ifreq {
511 struct in6_addr ifr6_addr;
512 __u32 ifr6_prefixlen;
513 unsigned int ifr6_ifindex;
514 };
515
516 //
517 // Set up TUN interface
518 static void inittun(void)
519 {
520 struct ifreq ifr;
521 struct in6_ifreq ifr6;
522 struct sockaddr_in sin = {0};
523 memset(&ifr, 0, sizeof(ifr));
524 ifr.ifr_flags = IFF_TUN;
525
526 tunfd = open(TUNDEVICE, O_RDWR);
527 if (tunfd < 0)
528 { // fatal
529 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
530 exit(1);
531 }
532 {
533 int flags = fcntl(tunfd, F_GETFL, 0);
534 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
535 }
536 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
537 {
538 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
539 exit(1);
540 }
541 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
542 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
543 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
544
545 sin.sin_family = AF_INET;
546 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
547 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
548
549 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
550 {
551 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
552 exit(1);
553 }
554 /* Bump up the qlen to deal with bursts from the network */
555 ifr.ifr_qlen = 1000;
556 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
557 {
558 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
559 exit(1);
560 }
561 /* set MTU to modem MRU */
562 ifr.ifr_mtu = MRU;
563 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
564 {
565 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
566 exit(1);
567 }
568 ifr.ifr_flags = IFF_UP;
569 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
570 {
571 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
572 exit(1);
573 }
574 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
575 {
576 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
577 exit(1);
578 }
579 tunidx = ifr.ifr_ifindex;
580
581 // Only setup IPv6 on the tun device if we have a configured prefix
582 if (config->ipv6_prefix.s6_addr[0]) {
583 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
584
585 // Link local address is FE80::1
586 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
587 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
588 ifr6.ifr6_addr.s6_addr[1] = 0x80;
589 ifr6.ifr6_addr.s6_addr[15] = 1;
590 ifr6.ifr6_prefixlen = 64;
591 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
592 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
593 {
594 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
595 " %s\n", strerror(errno));
596 }
597
598 // Global address is prefix::1
599 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
600 ifr6.ifr6_addr = config->ipv6_prefix;
601 ifr6.ifr6_addr.s6_addr[15] = 1;
602 ifr6.ifr6_prefixlen = 64;
603 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
604 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
605 {
606 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
607 strerror(errno));
608 }
609 }
610 }
611
612 // set up UDP ports
613 static void initudp(void)
614 {
615 int on = 1;
616 struct sockaddr_in addr;
617
618 // Tunnel
619 memset(&addr, 0, sizeof(addr));
620 addr.sin_family = AF_INET;
621 addr.sin_port = htons(L2TPPORT);
622 addr.sin_addr.s_addr = config->bind_address;
623 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
624 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
625 {
626 int flags = fcntl(udpfd, F_GETFL, 0);
627 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
628 }
629 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
630 {
631 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
632 exit(1);
633 }
634
635 // Control
636 memset(&addr, 0, sizeof(addr));
637 addr.sin_family = AF_INET;
638 addr.sin_port = htons(NSCTL_PORT);
639 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
640 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
641 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
642 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
643 {
644 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
645 exit(1);
646 }
647
648 // Dynamic Authorization Extensions to RADIUS
649 memset(&addr, 0, sizeof(addr));
650 addr.sin_family = AF_INET;
651 addr.sin_port = htons(config->radius_dae_port);
652 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
653 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
654 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
655 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
656 {
657 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
658 exit(1);
659 }
660
661 // Intercept
662 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
663 }
664
665 //
666 // Find session by IP, < 1 for not found
667 //
668 // Confusingly enough, this 'ip' must be
669 // in _network_ order. This being the common
670 // case when looking it up from IP packet headers.
671 //
672 // We actually use this cache for two things.
673 // #1. For used IP addresses, this maps to the
674 // session ID that it's used by.
675 // #2. For un-used IP addresses, this maps to the
676 // index into the pool table that contains that
677 // IP address.
678 //
679
680 static int lookup_ipmap(in_addr_t ip)
681 {
682 uint8_t *a = (uint8_t *) &ip;
683 uint8_t **d = (uint8_t **) ip_hash;
684
685 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
686 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
687 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
688
689 return (int) (intptr_t) d[(size_t) *a];
690 }
691
692 static int lookup_ipv6map(struct in6_addr ip)
693 {
694 struct ipv6radix *curnode;
695 int i;
696 int s;
697 char ipv6addr[INET6_ADDRSTRLEN];
698
699 curnode = &ipv6_hash[ip.s6_addr[0]];
700 i = 1;
701 s = curnode->sess;
702
703 while (s == 0 && i < 15 && curnode->branch != NULL)
704 {
705 curnode = &curnode->branch[ip.s6_addr[i]];
706 s = curnode->sess;
707 i++;
708 }
709
710 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
711 inet_ntop(AF_INET6, &ip, ipv6addr,
712 INET6_ADDRSTRLEN),
713 s);
714
715 return s;
716 }
717
718 sessionidt sessionbyip(in_addr_t ip)
719 {
720 int s = lookup_ipmap(ip);
721 CSTAT(sessionbyip);
722
723 if (s > 0 && s < MAXSESSION && session[s].opened)
724 return (sessionidt) s;
725
726 return 0;
727 }
728
729 sessionidt sessionbyipv6(struct in6_addr ip)
730 {
731 int s;
732 CSTAT(sessionbyipv6);
733
734 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
735 (ip.s6_addr[0] == 0xFE &&
736 ip.s6_addr[1] == 0x80 &&
737 ip.s6_addr16[1] == 0 &&
738 ip.s6_addr16[2] == 0 &&
739 ip.s6_addr16[3] == 0)) {
740 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
741 } else {
742 s = lookup_ipv6map(ip);
743 }
744
745 if (s > 0 && s < MAXSESSION && session[s].opened)
746 return s;
747
748 return 0;
749 }
750
751 //
752 // Take an IP address in HOST byte order and
753 // add it to the sessionid by IP cache.
754 //
755 // (It's actually cached in network order)
756 //
757 static void cache_ipmap(in_addr_t ip, int s)
758 {
759 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
760 uint8_t *a = (uint8_t *) &nip;
761 uint8_t **d = (uint8_t **) ip_hash;
762 int i;
763
764 for (i = 0; i < 3; i++)
765 {
766 if (!d[(size_t) a[i]])
767 {
768 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
769 return;
770 }
771
772 d = (uint8_t **) d[(size_t) a[i]];
773 }
774
775 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
776
777 if (s > 0)
778 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
779
780 else if (s == 0)
781 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
782 // else a map to an ip pool index.
783 }
784
785 static void uncache_ipmap(in_addr_t ip)
786 {
787 cache_ipmap(ip, 0); // Assign it to the NULL session.
788 }
789
790 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
791 {
792 int i;
793 int bytes;
794 struct ipv6radix *curnode;
795 char ipv6addr[INET6_ADDRSTRLEN];
796
797 curnode = &ipv6_hash[ip.s6_addr[0]];
798
799 bytes = prefixlen >> 3;
800 i = 1;
801 while (i < bytes) {
802 if (curnode->branch == NULL)
803 {
804 if (!(curnode->branch = calloc(256,
805 sizeof (struct ipv6radix))))
806 return;
807 }
808 curnode = &curnode->branch[ip.s6_addr[i]];
809 i++;
810 }
811
812 curnode->sess = s;
813
814 if (s > 0)
815 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
816 inet_ntop(AF_INET6, &ip, ipv6addr,
817 INET6_ADDRSTRLEN),
818 prefixlen);
819 else if (s == 0)
820 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
821 inet_ntop(AF_INET6, &ip, ipv6addr,
822 INET6_ADDRSTRLEN),
823 prefixlen);
824 }
825
826 //
827 // CLI list to dump current ipcache.
828 //
829 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
830 {
831 char **d = (char **) ip_hash, **e, **f, **g;
832 int i, j, k, l;
833 int count = 0;
834
835 if (CLI_HELP_REQUESTED)
836 return CLI_HELP_NO_ARGS;
837
838 cli_print(cli, "%7s %s", "Sess#", "IP Address");
839
840 for (i = 0; i < 256; ++i)
841 {
842 if (!d[i])
843 continue;
844 e = (char **) d[i];
845 for (j = 0; j < 256; ++j)
846 {
847 if (!e[j])
848 continue;
849 f = (char **) e[j];
850 for (k = 0; k < 256; ++k)
851 {
852 if (!f[k])
853 continue;
854 g = (char **)f[k];
855 for (l = 0; l < 256; ++l)
856 {
857 if (!g[l])
858 continue;
859 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
860 ++count;
861 }
862 }
863 }
864 }
865 cli_print(cli, "%d entries in cache", count);
866 return CLI_OK;
867 }
868
869
870 // Find session by username, 0 for not found
871 // walled garden users aren't authenticated, so the username is
872 // reasonably useless. Ignore them to avoid incorrect actions
873 //
874 // This is VERY inefficent. Don't call it often. :)
875 //
876 sessionidt sessionbyuser(char *username)
877 {
878 int s;
879 CSTAT(sessionbyuser);
880
881 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
882 {
883 if (!session[s].opened)
884 continue;
885
886 if (session[s].walled_garden)
887 continue; // Skip walled garden users.
888
889 if (!strncmp(session[s].user, username, 128))
890 return s;
891
892 }
893 return 0; // Not found.
894 }
895
896 void send_garp(in_addr_t ip)
897 {
898 int s;
899 struct ifreq ifr;
900 uint8_t mac[6];
901
902 s = socket(PF_INET, SOCK_DGRAM, 0);
903 if (s < 0)
904 {
905 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
906 return;
907 }
908 memset(&ifr, 0, sizeof(ifr));
909 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
910 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
911 {
912 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
913 close(s);
914 return;
915 }
916 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
917 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
918 {
919 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
920 close(s);
921 return;
922 }
923 close(s);
924 sendarp(ifr.ifr_ifindex, mac, ip);
925 }
926
927 static sessiont *sessiontbysessionidt(sessionidt s)
928 {
929 if (!s || s >= MAXSESSION) return NULL;
930 return &session[s];
931 }
932
933 static sessionidt sessionidtbysessiont(sessiont *s)
934 {
935 sessionidt val = s-session;
936 if (s < session || val >= MAXSESSION) return 0;
937 return val;
938 }
939
940 // actually send a control message for a specific tunnel
941 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
942 {
943 struct sockaddr_in addr;
944
945 CSTAT(tunnelsend);
946
947 if (!t)
948 {
949 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
950 STAT(tunnel_tx_errors);
951 return;
952 }
953
954 if (!tunnel[t].ip)
955 {
956 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
957 STAT(tunnel_tx_errors);
958 return;
959 }
960
961 memset(&addr, 0, sizeof(addr));
962 addr.sin_family = AF_INET;
963 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
964 addr.sin_port = htons(tunnel[t].port);
965
966 // sequence expected, if sequence in message
967 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
968
969 // If this is a control message, deal with retries
970 if (*buf & 0x80)
971 {
972 tunnel[t].last = time_now; // control message sent
973 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
974 if (tunnel[t].try)
975 {
976 STAT(tunnel_retries);
977 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
978 }
979 }
980
981 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
982 {
983 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
984 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
985 STAT(tunnel_tx_errors);
986 return;
987 }
988
989 LOG_HEX(5, "Send Tunnel Data", buf, l);
990 STAT(tunnel_tx_packets);
991 INC_STAT(tunnel_tx_bytes, l);
992 }
993
994 //
995 // Tiny helper function to write data to
996 // the 'tun' device.
997 //
998 int tun_write(uint8_t * data, int size)
999 {
1000 return write(tunfd, data, size);
1001 }
1002
1003 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1004 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1005 {
1006 int d = (tcp[12] >> 4) * 4;
1007 uint8_t *mss = 0;
1008 uint8_t *opts;
1009 uint8_t *data;
1010 uint16_t orig;
1011 uint32_t sum;
1012
1013 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1014 return;
1015
1016 if (tcp + d > buf + len) // short?
1017 return;
1018
1019 opts = tcp + 20;
1020 data = tcp + d;
1021
1022 while (opts < data)
1023 {
1024 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1025 {
1026 mss = opts + 2;
1027 if (mss + 2 > data) return; // short?
1028 break;
1029 }
1030
1031 if (*opts == 0) return; // end of options
1032 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1033 opts++;
1034 else
1035 opts += opts[1]; // skip over option
1036 }
1037
1038 if (!mss) return; // not found
1039 orig = ntohs(*(uint16_t *) mss);
1040
1041 if (orig <= MSS) return; // mss OK
1042
1043 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1044 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1045 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1046 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1047
1048 // set mss
1049 *(int16_t *) mss = htons(MSS);
1050
1051 // adjust checksum (see rfc1141)
1052 sum = orig + (~MSS & 0xffff);
1053 sum += ntohs(*(uint16_t *) (tcp + 16));
1054 sum = (sum & 0xffff) + (sum >> 16);
1055 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1056 }
1057
1058 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
1059 {
1060 uint16_t proto;
1061 if (extra) {
1062 // Skip the four extra bytes
1063 p += 4;
1064 l -= 4;
1065 }
1066
1067 // Process this frame
1068 if (*p & 1)
1069 {
1070 proto = *p++;
1071 l--;
1072 }
1073 else
1074 {
1075 proto = ntohs(*(uint16_t *) p);
1076 p += 2;
1077 l -= 2;
1078 }
1079 if (proto == PPPIP)
1080 {
1081 if (session[s].die)
1082 {
1083 LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s);
1084 return; // closing session, PPP not processed
1085 }
1086 session[s].last_packet = time_now;
1087 processipin(s, t, p, l);
1088 }
1089 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
1090 {
1091 if (session[s].die)
1092 {
1093 LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s);
1094 return; // closing session, PPP not processed
1095 }
1096
1097 session[s].last_packet = time_now;
1098 processipv6in(s, t, p, l);
1099 }
1100 else
1101 {
1102 LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
1103 }
1104 }
1105
1106 // process outgoing (to tunnel) IP
1107 //
1108 static void processipout(uint8_t *buf, int len)
1109 {
1110 sessionidt s;
1111 sessiont *sp;
1112 tunnelidt t;
1113 in_addr_t ip;
1114
1115 uint8_t *data = buf; // Keep a copy of the originals.
1116 int size = len;
1117
1118 uint8_t b1[MAXETHER + 20];
1119 uint8_t b2[MAXETHER + 20];
1120
1121 CSTAT(processipout);
1122
1123 if (len < MIN_IP_SIZE)
1124 {
1125 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1126 STAT(tun_rx_errors);
1127 return;
1128 }
1129 if (len >= MAXETHER)
1130 {
1131 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1132 STAT(tun_rx_errors);
1133 return;
1134 }
1135
1136 // Skip the tun header
1137 buf += 4;
1138 len -= 4;
1139
1140 // Got an IP header now
1141 if (*(uint8_t *)(buf) >> 4 != 4)
1142 {
1143 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1144 return;
1145 }
1146
1147 ip = *(uint32_t *)(buf + 16);
1148 if (!(s = sessionbyip(ip)))
1149 {
1150 // Is this a packet for a session that doesn't exist?
1151 static int rate = 0; // Number of ICMP packets we've sent this second.
1152 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1153
1154 if (last != time_now)
1155 {
1156 last = time_now;
1157 rate = 0;
1158 }
1159
1160 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1161 {
1162 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1163 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1164 config->bind_address ? config->bind_address : my_address, buf, len);
1165 }
1166 return;
1167 }
1168 t = session[s].tunnel;
1169 sp = &session[s];
1170
1171 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1172 if (config->max_packets > 0)
1173 {
1174 if (sess_local[s].last_packet_out == TIME)
1175 {
1176 int max = config->max_packets;
1177
1178 // All packets for throttled sessions are handled by the
1179 // master, so further limit by using the throttle rate.
1180 // A bit of a kludge, since throttle rate is in kbps,
1181 // but should still be generous given our average DSL
1182 // packet size is 200 bytes: a limit of 28kbps equates
1183 // to around 180 packets per second.
1184 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1185 max = sp->throttle_out;
1186
1187 if (++sess_local[s].packets_out > max)
1188 {
1189 sess_local[s].packets_dropped++;
1190 return;
1191 }
1192 }
1193 else
1194 {
1195 if (sess_local[s].packets_dropped)
1196 {
1197 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1198 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1199 sess_local[s].packets_dropped, sess_local[s].packets_out,
1200 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1201 sp->user);
1202 }
1203
1204 sess_local[s].last_packet_out = TIME;
1205 sess_local[s].packets_out = 1;
1206 sess_local[s].packets_dropped = 0;
1207 }
1208 }
1209
1210 // run access-list if any
1211 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1212 return;
1213
1214 // adjust MSS on SYN and SYN,ACK packets with options
1215 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1216 {
1217 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1218 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1219 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1220 }
1221
1222 if (sp->tbf_out)
1223 {
1224 // Are we throttling this session?
1225 if (config->cluster_iam_master)
1226 tbf_queue_packet(sp->tbf_out, data, size);
1227 else
1228 master_throttle_packet(sp->tbf_out, data, size);
1229 return;
1230 }
1231
1232 if (sp->walled_garden && !config->cluster_iam_master)
1233 {
1234 // We are walled-gardening this
1235 master_garden_packet(s, data, size);
1236 return;
1237 }
1238
1239 // Add on L2TP header
1240 {
1241 bundleidt bid = 0;
1242 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1243 {
1244 bid = session[s].bundle;
1245 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1246 LOG(4, s, t, "MPPP: (1)Session number becomes: %d\n", s);
1247 if (len > 256)
1248 {
1249 // Partition the packet to 2 fragments
1250 uint32_t frag1len = len / 2;
1251 uint32_t frag2len = len - frag1len;
1252 uint8_t *p = makeppp(b1, sizeof(b1), buf, frag1len, s, t, PPPIP, 0, bid, MP_BEGIN);
1253 uint8_t *q;
1254
1255 if (!p) return;
1256 tunnelsend(b1, frag1len + (p-b1), t); // send it...
1257 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1258 LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s);
1259 q = makeppp(b2, sizeof(b2), buf+frag1len, frag2len, s, t, PPPIP, 0, bid, MP_END);
1260 if (!q) return;
1261 tunnelsend(b2, frag2len + (q-b2), t); // send it...
1262 }
1263 else {
1264 // Send it as one frame
1265 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
1266 if (!p) return;
1267 tunnelsend(b1, len + (p-b1), t); // send it...
1268 }
1269 }
1270 else
1271 {
1272 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, 0, 0);
1273 if (!p) return;
1274 tunnelsend(b1, len + (p-b1), t); // send it...
1275 }
1276 }
1277
1278 // Snooping this session, send it to intercept box
1279 if (sp->snoop_ip && sp->snoop_port)
1280 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1281
1282 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1283 sp->cout_delta += len;
1284 sp->pout++;
1285 udp_tx += len;
1286
1287 sess_local[s].cout += len; // To send to master..
1288 sess_local[s].pout++;
1289 }
1290
1291 // process outgoing (to tunnel) IPv6
1292 //
1293 static void processipv6out(uint8_t * buf, int len)
1294 {
1295 sessionidt s;
1296 sessiont *sp;
1297 tunnelidt t;
1298 in_addr_t ip;
1299 struct in6_addr ip6;
1300
1301 uint8_t *data = buf; // Keep a copy of the originals.
1302 int size = len;
1303
1304 uint8_t b[MAXETHER + 20];
1305
1306 CSTAT(processipv6out);
1307
1308 if (len < MIN_IP_SIZE)
1309 {
1310 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1311 STAT(tunnel_tx_errors);
1312 return;
1313 }
1314 if (len >= MAXETHER)
1315 {
1316 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1317 STAT(tunnel_tx_errors);
1318 return;
1319 }
1320
1321 // Skip the tun header
1322 buf += 4;
1323 len -= 4;
1324
1325 // Got an IP header now
1326 if (*(uint8_t *)(buf) >> 4 != 6)
1327 {
1328 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1329 return;
1330 }
1331
1332 ip6 = *(struct in6_addr *)(buf+24);
1333 s = sessionbyipv6(ip6);
1334
1335 if (s == 0)
1336 {
1337 ip = *(uint32_t *)(buf + 32);
1338 s = sessionbyip(ip);
1339 }
1340
1341 if (s == 0)
1342 {
1343 // Is this a packet for a session that doesn't exist?
1344 static int rate = 0; // Number of ICMP packets we've sent this second.
1345 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1346
1347 if (last != time_now)
1348 {
1349 last = time_now;
1350 rate = 0;
1351 }
1352
1353 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1354 {
1355 // FIXME: Should send icmp6 host unreachable
1356 }
1357 return;
1358 }
1359 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1360 {
1361 bundleidt bid = session[s].bundle;
1362 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1363 LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %d\n", s);
1364 }
1365 t = session[s].tunnel;
1366 sp = &session[s];
1367
1368 // FIXME: add DoS prevention/filters?
1369
1370 if (sp->tbf_out)
1371 {
1372 // Are we throttling this session?
1373 if (config->cluster_iam_master)
1374 tbf_queue_packet(sp->tbf_out, data, size);
1375 else
1376 master_throttle_packet(sp->tbf_out, data, size);
1377 return;
1378 }
1379 else if (sp->walled_garden && !config->cluster_iam_master)
1380 {
1381 // We are walled-gardening this
1382 master_garden_packet(s, data, size);
1383 return;
1384 }
1385
1386 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1387
1388 // Add on L2TP header
1389 {
1390 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
1391 if (!p) return;
1392 tunnelsend(b, len + (p-b), t); // send it...
1393 }
1394
1395 // Snooping this session, send it to intercept box
1396 if (sp->snoop_ip && sp->snoop_port)
1397 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1398
1399 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1400 sp->cout_delta += len;
1401 sp->pout++;
1402 udp_tx += len;
1403
1404 sess_local[s].cout += len; // To send to master..
1405 sess_local[s].pout++;
1406 }
1407
1408 //
1409 // Helper routine for the TBF filters.
1410 // Used to send queued data in to the user!
1411 //
1412 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1413 {
1414 sessiont *sp;
1415 tunnelidt t;
1416 in_addr_t ip;
1417
1418 uint8_t b[MAXETHER + 20];
1419
1420 if (len < 0 || len > MAXETHER)
1421 {
1422 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1423 return;
1424 }
1425
1426 // Skip the tun header
1427 buf += 4;
1428 len -= 4;
1429
1430 ip = *(in_addr_t *)(buf + 16);
1431
1432 if (!session[s].ip)
1433 return;
1434
1435 t = session[s].tunnel;
1436 sp = &session[s];
1437
1438 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1439
1440 // Add on L2TP header
1441 {
1442 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
1443 if (!p) return;
1444 tunnelsend(b, len + (p-b), t); // send it...
1445 }
1446
1447 // Snooping this session.
1448 if (sp->snoop_ip && sp->snoop_port)
1449 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1450
1451 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1452 sp->cout_delta += len;
1453 sp->pout++;
1454 udp_tx += len;
1455
1456 sess_local[s].cout += len; // To send to master..
1457 sess_local[s].pout++;
1458 }
1459
1460 // add an AVP (16 bit)
1461 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1462 {
1463 uint16_t l = (m ? 0x8008 : 0x0008);
1464 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1465 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1466 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1467 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1468 c->length += 8;
1469 }
1470
1471 // add an AVP (32 bit)
1472 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1473 {
1474 uint16_t l = (m ? 0x800A : 0x000A);
1475 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1476 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1477 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1478 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1479 c->length += 10;
1480 }
1481
1482 // add an AVP (string)
1483 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1484 {
1485 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1486 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1487 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1488 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1489 memcpy(c->buf + c->length + 6, val, strlen(val));
1490 c->length += 6 + strlen(val);
1491 }
1492
1493 // add a binary AVP
1494 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1495 {
1496 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1497 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1498 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1499 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1500 memcpy(c->buf + c->length + 6, val, len);
1501 c->length += 6 + len;
1502 }
1503
1504 // new control connection
1505 static controlt *controlnew(uint16_t mtype)
1506 {
1507 controlt *c;
1508 if (!controlfree)
1509 c = malloc(sizeof(controlt));
1510 else
1511 {
1512 c = controlfree;
1513 controlfree = c->next;
1514 }
1515 assert(c);
1516 c->next = 0;
1517 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1518 c->length = 12;
1519 control16(c, 0, mtype, 1);
1520 return c;
1521 }
1522
1523 // send zero block if nothing is waiting
1524 // (ZLB send).
1525 static void controlnull(tunnelidt t)
1526 {
1527 uint8_t buf[12];
1528 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1529 return;
1530
1531 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1532 *(uint16_t *) (buf + 2) = htons(12); // length
1533 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1534 *(uint16_t *) (buf + 6) = htons(0); // session
1535 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1536 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1537 tunnelsend(buf, 12, t);
1538 }
1539
1540 // add a control message to a tunnel, and send if within window
1541 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1542 {
1543 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1544 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1545 *(uint16_t *) (c->buf + 6) = htons(far); // session
1546 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1547 tunnel[t].ns++; // advance sequence
1548 // link in message in to queue
1549 if (tunnel[t].controlc)
1550 tunnel[t].controle->next = c;
1551 else
1552 tunnel[t].controls = c;
1553
1554 tunnel[t].controle = c;
1555 tunnel[t].controlc++;
1556
1557 // send now if space in window
1558 if (tunnel[t].controlc <= tunnel[t].window)
1559 {
1560 tunnel[t].try = 0; // first send
1561 tunnelsend(c->buf, c->length, t);
1562 }
1563 }
1564
1565 //
1566 // Throttle or Unthrottle a session
1567 //
1568 // Throttle the data from/to through a session to no more than
1569 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1570 // user).
1571 //
1572 // If either value is -1, the current value is retained for that
1573 // direction.
1574 //
1575 void throttle_session(sessionidt s, int rate_in, int rate_out)
1576 {
1577 if (!session[s].opened)
1578 return; // No-one home.
1579
1580 if (!*session[s].user)
1581 return; // User not logged in
1582
1583 if (rate_in >= 0)
1584 {
1585 int bytes = rate_in * 1024 / 8; // kbits to bytes
1586 if (session[s].tbf_in)
1587 free_tbf(session[s].tbf_in);
1588
1589 if (rate_in > 0)
1590 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1591 else
1592 session[s].tbf_in = 0;
1593
1594 session[s].throttle_in = rate_in;
1595 }
1596
1597 if (rate_out >= 0)
1598 {
1599 int bytes = rate_out * 1024 / 8;
1600 if (session[s].tbf_out)
1601 free_tbf(session[s].tbf_out);
1602
1603 if (rate_out > 0)
1604 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1605 else
1606 session[s].tbf_out = 0;
1607
1608 session[s].throttle_out = rate_out;
1609 }
1610 }
1611
1612 // add/remove filters from session (-1 = no change)
1613 void filter_session(sessionidt s, int filter_in, int filter_out)
1614 {
1615 if (!session[s].opened)
1616 return; // No-one home.
1617
1618 if (!*session[s].user)
1619 return; // User not logged in
1620
1621 // paranoia
1622 if (filter_in > MAXFILTER) filter_in = -1;
1623 if (filter_out > MAXFILTER) filter_out = -1;
1624 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1625 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1626
1627 if (filter_in >= 0)
1628 {
1629 if (session[s].filter_in)
1630 ip_filters[session[s].filter_in - 1].used--;
1631
1632 if (filter_in > 0)
1633 ip_filters[filter_in - 1].used++;
1634
1635 session[s].filter_in = filter_in;
1636 }
1637
1638 if (filter_out >= 0)
1639 {
1640 if (session[s].filter_out)
1641 ip_filters[session[s].filter_out - 1].used--;
1642
1643 if (filter_out > 0)
1644 ip_filters[filter_out - 1].used++;
1645
1646 session[s].filter_out = filter_out;
1647 }
1648 }
1649
1650 // start tidy shutdown of session
1651 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
1652 {
1653 int walled_garden = session[s].walled_garden;
1654
1655
1656 CSTAT(sessionshutdown);
1657
1658 if (!session[s].opened)
1659 {
1660 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1661 return; // not a live session
1662 }
1663
1664 if (!session[s].die)
1665 {
1666 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1667 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1668 run_plugins(PLUGIN_KILL_SESSION, &data);
1669 }
1670
1671 if (session[s].ip && !walled_garden && !session[s].die)
1672 {
1673 // RADIUS Stop message
1674 uint16_t r = radiusnew(s);
1675 if (r)
1676 {
1677 // stop, if not already trying
1678 if (radius[r].state != RADIUSSTOP)
1679 {
1680 radius[r].term_cause = term_cause;
1681 radius[r].term_msg = reason;
1682 radiussend(r, RADIUSSTOP);
1683 }
1684 }
1685 else
1686 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1687
1688 // Save counters to dump to accounting file
1689 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1690 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1691 }
1692
1693 if (session[s].ip)
1694 { // IP allocated, clear and unroute
1695 int r;
1696 int routed = 0;
1697 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1698 {
1699 if ((session[s].ip & session[s].route[r].mask) ==
1700 (session[s].route[r].ip & session[s].route[r].mask))
1701 routed++;
1702
1703 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1704 session[s].route[r].ip = 0;
1705 }
1706
1707 if (session[s].ip_pool_index == -1) // static ip
1708 {
1709 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1710 session[s].ip = 0;
1711 }
1712 else
1713 free_ip_address(s);
1714
1715 // unroute IPv6, if setup
1716 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1717 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1718 }
1719
1720 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1721 throttle_session(s, 0, 0);
1722
1723 if (cdn_result)
1724 { // Send CDN
1725 controlt *c = controlnew(14); // sending CDN
1726 if (cdn_error)
1727 {
1728 uint8_t buf[4];
1729 *(uint16_t *) buf = htons(cdn_result);
1730 *(uint16_t *) (buf+2) = htons(cdn_error);
1731 controlb(c, 1, buf, 4, 1);
1732 }
1733 else
1734 control16(c, 1, cdn_result, 1);
1735
1736 control16(c, 14, s, 1); // assigned session (our end)
1737 controladd(c, session[s].far, session[s].tunnel); // send the message
1738 }
1739
1740 if (!session[s].die)
1741 session[s].die = TIME + 150; // Clean up in 15 seconds
1742
1743 // update filter refcounts
1744 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1745 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1746
1747 // clear PPP state
1748 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1749 sess_local[s].lcp.restart = 0;
1750 sess_local[s].ipcp.restart = 0;
1751 sess_local[s].ipv6cp.restart = 0;
1752 sess_local[s].ccp.restart = 0;
1753
1754 cluster_send_session(s);
1755 }
1756
1757 void sendipcp(sessionidt s, tunnelidt t)
1758 {
1759 uint8_t buf[MAXETHER];
1760 uint8_t *q;
1761
1762 CSTAT(sendipcp);
1763 LOG(3, s, t, "IPCP: send ConfigReq\n");
1764
1765 if (!session[s].unique_id)
1766 {
1767 if (!++last_id) ++last_id; // skip zero
1768 session[s].unique_id = last_id;
1769 }
1770
1771 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
1772 if (!q) return;
1773
1774 *q = ConfigReq;
1775 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1776 *(uint16_t *) (q + 2) = htons(10); // packet length
1777 q[4] = 3; // ip address option
1778 q[5] = 6; // option length
1779 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1780 config->bind_address ? config->bind_address :
1781 my_address; // send my IP
1782
1783 tunnelsend(buf, 10 + (q - buf), t); // send it
1784 restart_timer(s, ipcp);
1785 }
1786
1787 void sendipv6cp(sessionidt s, tunnelidt t)
1788 {
1789 uint8_t buf[MAXETHER];
1790 uint8_t *q;
1791
1792 CSTAT(sendipv6cp);
1793 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1794
1795 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
1796 if (!q) return;
1797
1798 *q = ConfigReq;
1799 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1800 // only send one type
1801 // of request
1802 *(uint16_t *) (q + 2) = htons(14);
1803 q[4] = 1; // interface identifier option
1804 q[5] = 10; // option length
1805 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1806 *(uint32_t *) (q + 10) = 0;
1807 q[13] = 1;
1808
1809 tunnelsend(buf, 14 + (q - buf), t); // send it
1810 restart_timer(s, ipv6cp);
1811 }
1812
1813 static void sessionclear(sessionidt s)
1814 {
1815 memset(&session[s], 0, sizeof(session[s]));
1816 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1817 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1818
1819 session[s].tunnel = T_FREE; // Mark it as free.
1820 session[s].next = sessionfree;
1821 sessionfree = s;
1822 }
1823
1824 // kill a session now
1825 void sessionkill(sessionidt s, char *reason)
1826 {
1827 bundleidt b;
1828
1829 CSTAT(sessionkill);
1830
1831 if (!session[s].opened) // not alive
1832 return;
1833
1834 if (session[s].next)
1835 {
1836 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1837 return;
1838 }
1839
1840 session[s].die = TIME;
1841 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
1842 if (sess_local[s].radius)
1843 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1844
1845 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1846 if ((b = session[s].bundle))
1847 {
1848 // This session was part of a bundle
1849 bundle[b].num_of_links--;
1850 LOG(3, s, 0, "MPPP: Dropping member link: %d from bundle %d\n",s,b);
1851 if (bundle[b].num_of_links == 0)
1852 {
1853 bundleclear(b);
1854 LOG(3, s, 0, "MPPP: Kill bundle: %d (No remaing member links)\n",b);
1855 }
1856 else
1857 {
1858 // Adjust the members array to accomodate the new change
1859 uint8_t mem_num = 0;
1860 // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
1861 if (bundle[b].members[bundle[b].num_of_links] != s)
1862 {
1863 uint8_t ml;
1864 for (ml = 0; ml<bundle[b].num_of_links; ml++)
1865 {
1866 if (bundle[b].members[ml] == s)
1867 {
1868 mem_num = ml;
1869 break;
1870 }
1871 }
1872 bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
1873 LOG(3, s, 0, "MPPP: Adjusted member links array\n");
1874 }
1875 }
1876 cluster_send_bundle(b);
1877 }
1878 sessionclear(s);
1879 cluster_send_session(s);
1880 }
1881
1882 static void tunnelclear(tunnelidt t)
1883 {
1884 if (!t) return;
1885 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1886 tunnel[t].state = TUNNELFREE;
1887 }
1888
1889 static void bundleclear(bundleidt b)
1890 {
1891 if (!b) return;
1892 memset(&bundle[b], 0, sizeof(bundle[b]));
1893 bundle[b].state = BUNDLEFREE;
1894 }
1895
1896 // kill a tunnel now
1897 static void tunnelkill(tunnelidt t, char *reason)
1898 {
1899 sessionidt s;
1900 controlt *c;
1901
1902 CSTAT(tunnelkill);
1903
1904 tunnel[t].state = TUNNELDIE;
1905
1906 // free control messages
1907 while ((c = tunnel[t].controls))
1908 {
1909 controlt * n = c->next;
1910 tunnel[t].controls = n;
1911 tunnel[t].controlc--;
1912 c->next = controlfree;
1913 controlfree = c;
1914 }
1915 // kill sessions
1916 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1917 if (session[s].tunnel == t)
1918 sessionkill(s, reason);
1919
1920 // free tunnel
1921 tunnelclear(t);
1922 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1923 cli_tunnel_actions[t].action = 0;
1924 cluster_send_tunnel(t);
1925 }
1926
1927 // shut down a tunnel cleanly
1928 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1929 {
1930 sessionidt s;
1931
1932 CSTAT(tunnelshutdown);
1933
1934 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1935 {
1936 // never set up, can immediately kill
1937 tunnelkill(t, reason);
1938 return;
1939 }
1940 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1941
1942 // close session
1943 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1944 if (session[s].tunnel == t)
1945 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
1946
1947 tunnel[t].state = TUNNELDIE;
1948 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1949 cluster_send_tunnel(t);
1950 // TBA - should we wait for sessions to stop?
1951 if (result)
1952 {
1953 controlt *c = controlnew(4); // sending StopCCN
1954 if (error)
1955 {
1956 uint8_t buf[64];
1957 int l = 4;
1958 *(uint16_t *) buf = htons(result);
1959 *(uint16_t *) (buf+2) = htons(error);
1960 if (msg)
1961 {
1962 int m = strlen(msg);
1963 if (m + 4 > sizeof(buf))
1964 m = sizeof(buf) - 4;
1965
1966 memcpy(buf+4, msg, m);
1967 l += m;
1968 }
1969
1970 controlb(c, 1, buf, l, 1);
1971 }
1972 else
1973 control16(c, 1, result, 1);
1974
1975 control16(c, 9, t, 1); // assigned tunnel (our end)
1976 controladd(c, 0, t); // send the message
1977 }
1978 }
1979
1980 // read and process packet on tunnel (UDP)
1981 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1982 {
1983 uint8_t *chapresponse = NULL;
1984 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1985 uint8_t *p = buf + 2;
1986
1987
1988 CSTAT(processudp);
1989
1990 udp_rx += len;
1991 udp_rx_pkt++;
1992 LOG_HEX(5, "UDP Data", buf, len);
1993 STAT(tunnel_rx_packets);
1994 INC_STAT(tunnel_rx_bytes, len);
1995 if (len < 6)
1996 {
1997 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1998 STAT(tunnel_rx_errors);
1999 return;
2000 }
2001 if ((buf[1] & 0x0F) != 2)
2002 {
2003 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
2004 STAT(tunnel_rx_errors);
2005 return;
2006 }
2007 if (*buf & 0x40)
2008 { // length
2009 l = ntohs(*(uint16_t *) p);
2010 p += 2;
2011 }
2012 t = ntohs(*(uint16_t *) p);
2013 p += 2;
2014 s = ntohs(*(uint16_t *) p);
2015 p += 2;
2016 if (s >= MAXSESSION)
2017 {
2018 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
2019 STAT(tunnel_rx_errors);
2020 return;
2021 }
2022 if (t >= MAXTUNNEL)
2023 {
2024 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
2025 STAT(tunnel_rx_errors);
2026 return;
2027 }
2028 if (*buf & 0x08)
2029 { // ns/nr
2030 ns = ntohs(*(uint16_t *) p);
2031 p += 2;
2032 nr = ntohs(*(uint16_t *) p);
2033 p += 2;
2034 }
2035 if (*buf & 0x02)
2036 { // offset
2037 uint16_t o = ntohs(*(uint16_t *) p);
2038 p += o + 2;
2039 }
2040 if ((p - buf) > l)
2041 {
2042 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
2043 STAT(tunnel_rx_errors);
2044 return;
2045 }
2046 l -= (p - buf);
2047
2048 // used to time out old tunnels
2049 if (t && tunnel[t].state == TUNNELOPEN)
2050 tunnel[t].lastrec = time_now;
2051
2052 if (*buf & 0x80)
2053 { // control
2054 uint16_t message = 0xFFFF; // message type
2055 uint8_t fatal = 0;
2056 uint8_t mandatory = 0;
2057 uint16_t asession = 0; // assigned session
2058 uint32_t amagic = 0; // magic number
2059 uint8_t aflags = 0; // flags from last LCF
2060 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
2061 char called[MAXTEL] = ""; // called number
2062 char calling[MAXTEL] = ""; // calling number
2063
2064 if (!config->cluster_iam_master)
2065 {
2066 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2067 return;
2068 }
2069
2070 // control messages must have bits 0x80|0x40|0x08
2071 // (type, length and sequence) set, and bits 0x02|0x01
2072 // (offset and priority) clear
2073 if ((*buf & 0xCB) != 0xC8)
2074 {
2075 LOG(1, s, t, "Bad control header %02X\n", *buf);
2076 STAT(tunnel_rx_errors);
2077 return;
2078 }
2079
2080 // check for duplicate tunnel open message
2081 if (!t && ns == 0)
2082 {
2083 int i;
2084
2085 //
2086 // Is this a duplicate of the first packet? (SCCRQ)
2087 //
2088 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
2089 {
2090 if (tunnel[i].state != TUNNELOPENING ||
2091 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
2092 tunnel[i].port != ntohs(addr->sin_port) )
2093 continue;
2094 t = i;
2095 LOG(3, s, t, "Duplicate SCCRQ?\n");
2096 break;
2097 }
2098 }
2099
2100 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
2101 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
2102
2103 // if no tunnel specified, assign one
2104 if (!t)
2105 {
2106 if (!(t = new_tunnel()))
2107 {
2108 LOG(1, 0, 0, "No more tunnels\n");
2109 STAT(tunnel_overflow);
2110 return;
2111 }
2112 tunnelclear(t);
2113 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
2114 tunnel[t].port = ntohs(addr->sin_port);
2115 tunnel[t].window = 4; // default window
2116 STAT(tunnel_created);
2117 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
2118 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
2119 }
2120
2121 // If the 'ns' just received is not the 'nr' we're
2122 // expecting, just send an ack and drop it.
2123 //
2124 // if 'ns' is less, then we got a retransmitted packet.
2125 // if 'ns' is greater than missed a packet. Either way
2126 // we should ignore it.
2127 if (ns != tunnel[t].nr)
2128 {
2129 // is this the sequence we were expecting?
2130 STAT(tunnel_rx_errors);
2131 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
2132 t, ns, tunnel[t].nr);
2133
2134 if (l) // Is this not a ZLB?
2135 controlnull(t);
2136 return;
2137 }
2138
2139 // check sequence of this message
2140 {
2141 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2142 // some to clear maybe?
2143 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2144 {
2145 controlt *c = tunnel[t].controls;
2146 tunnel[t].controls = c->next;
2147 tunnel[t].controlc--;
2148 c->next = controlfree;
2149 controlfree = c;
2150 skip--;
2151 tunnel[t].try = 0; // we have progress
2152 }
2153
2154 // receiver advance (do here so quoted correctly in any sends below)
2155 if (l) tunnel[t].nr = (ns + 1);
2156 if (skip < 0) skip = 0;
2157 if (skip < tunnel[t].controlc)
2158 {
2159 // some control packets can now be sent that were previous stuck out of window
2160 int tosend = tunnel[t].window - skip;
2161 controlt *c = tunnel[t].controls;
2162 while (c && skip)
2163 {
2164 c = c->next;
2165 skip--;
2166 }
2167 while (c && tosend)
2168 {
2169 tunnel[t].try = 0; // first send
2170 tunnelsend(c->buf, c->length, t);
2171 c = c->next;
2172 tosend--;
2173 }
2174 }
2175 if (!tunnel[t].controlc)
2176 tunnel[t].retry = 0; // caught up
2177 }
2178 if (l)
2179 { // if not a null message
2180 int result = 0;
2181 int error = 0;
2182 char *msg = 0;
2183
2184 // default disconnect cause/message on receipt
2185 // of CDN (set to more specific value from
2186 // attribute 46 if present below).
2187 int disc_cause = TERM_NAS_REQUEST;
2188 char const *disc_reason = "Closed (Received CDN).";
2189
2190 // process AVPs
2191 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2192 {
2193 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2194 uint8_t *b = p;
2195 uint8_t flags = *p;
2196 uint16_t mtype;
2197
2198 if (n > l)
2199 {
2200 LOG(1, s, t, "Invalid length in AVP\n");
2201 STAT(tunnel_rx_errors);
2202 return;
2203 }
2204 p += n; // next
2205 l -= n;
2206 if (flags & 0x3C) // reserved bits, should be clear
2207 {
2208 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2209 fatal = flags;
2210 result = 2; // general error
2211 error = 3; // reserved field non-zero
2212 msg = 0;
2213 continue; // next
2214 }
2215 b += 2;
2216 if (*(uint16_t *) (b))
2217 {
2218 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2219 fatal = flags;
2220 result = 2; // general error
2221 error = 6; // generic vendor-specific error
2222 msg = "unsupported vendor-specific";
2223 continue; // next
2224 }
2225 b += 2;
2226 mtype = ntohs(*(uint16_t *) (b));
2227 b += 2;
2228 n -= 6;
2229
2230 if (flags & 0x40)
2231 {
2232 uint16_t orig_len;
2233
2234 // handle hidden AVPs
2235 if (!*config->l2tp_secret)
2236 {
2237 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2238 fatal = flags;
2239 result = 2; // general error
2240 error = 6; // generic vendor-specific error
2241 msg = "secret not specified";
2242 continue;
2243 }
2244 if (!session[s].random_vector_length)
2245 {
2246 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2247 fatal = flags;
2248 result = 2; // general error
2249 error = 6; // generic
2250 msg = "no random vector";
2251 continue;
2252 }
2253 if (n < 8)
2254 {
2255 LOG(2, s, t, "Short hidden AVP.\n");
2256 fatal = flags;
2257 result = 2; // general error
2258 error = 2; // length is wrong
2259 msg = 0;
2260 continue;
2261 }
2262
2263 // Unhide the AVP
2264 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2265
2266 orig_len = ntohs(*(uint16_t *) b);
2267 if (orig_len > n + 2)
2268 {
2269 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2270 orig_len, n);
2271
2272 fatal = flags;
2273 result = 2; // general error
2274 error = 2; // length is wrong
2275 msg = 0;
2276 continue;
2277 }
2278
2279 b += 2;
2280 n = orig_len;
2281 }
2282
2283 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2284 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2285
2286 switch (mtype)
2287 {
2288 case 0: // message type
2289 message = ntohs(*(uint16_t *) b);
2290 mandatory = flags & 0x80;
2291 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2292 break;
2293 case 1: // result code
2294 {
2295 uint16_t rescode = ntohs(*(uint16_t *) b);
2296 const char* resdesc = "(unknown)";
2297 if (message == 4)
2298 { /* StopCCN */
2299 resdesc = l2tp_stopccn_result_code(rescode);
2300 }
2301 else if (message == 14)
2302 { /* CDN */
2303 resdesc = l2tp_cdn_result_code(rescode);
2304 }
2305
2306 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2307 if (n >= 4)
2308 {
2309 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2310 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2311 }
2312 if (n > 4)
2313 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2314
2315 break;
2316 }
2317 break;
2318 case 2: // protocol version
2319 {
2320 version = ntohs(*(uint16_t *) (b));
2321 LOG(4, s, t, " Protocol version = %d\n", version);
2322 if (version && version != 0x0100)
2323 { // allow 0.0 and 1.0
2324 LOG(1, s, t, " Bad protocol version %04X\n", version);
2325 fatal = flags;
2326 result = 5; // unspported protocol version
2327 error = 0x0100; // supported version
2328 msg = 0;
2329 continue; // next
2330 }
2331 }
2332 break;
2333 case 3: // framing capabilities
2334 break;
2335 case 4: // bearer capabilities
2336 break;
2337 case 5: // tie breaker
2338 // We never open tunnels, so we don't care about tie breakers
2339 continue;
2340 case 6: // firmware revision
2341 break;
2342 case 7: // host name
2343 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2344 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2345 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2346 // TBA - to send to RADIUS
2347 break;
2348 case 8: // vendor name
2349 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2350 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2351 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2352 break;
2353 case 9: // assigned tunnel
2354 tunnel[t].far = ntohs(*(uint16_t *) (b));
2355 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2356 break;
2357 case 10: // rx window
2358 tunnel[t].window = ntohs(*(uint16_t *) (b));
2359 if (!tunnel[t].window)
2360 tunnel[t].window = 1; // window of 0 is silly
2361 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2362 break;
2363 case 11: // Challenge
2364 {
2365 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2366 build_chap_response(b, 2, n, &chapresponse);
2367 }
2368 break;
2369 case 13: // Response
2370 // Why did they send a response? We never challenge.
2371 LOG(2, s, t, " received unexpected challenge response\n");
2372 break;
2373
2374 case 14: // assigned session
2375 asession = session[s].far = ntohs(*(uint16_t *) (b));
2376 LOG(4, s, t, " assigned session = %d\n", asession);
2377 break;
2378 case 15: // call serial number
2379 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2380 break;
2381 case 18: // bearer type
2382 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2383 // TBA - for RADIUS
2384 break;
2385 case 19: // framing type
2386 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2387 // TBA
2388 break;
2389 case 21: // called number
2390 memset(called, 0, sizeof(called));
2391 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2392 LOG(4, s, t, " Called <%s>\n", called);
2393 break;
2394 case 22: // calling number
2395 memset(calling, 0, sizeof(calling));
2396 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2397 LOG(4, s, t, " Calling <%s>\n", calling);
2398 break;
2399 case 23: // subtype
2400 break;
2401 case 24: // tx connect speed
2402 if (n == 4)
2403 {
2404 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2405 }
2406 else
2407 {
2408 // AS5300s send connect speed as a string
2409 char tmp[30];
2410 memset(tmp, 0, sizeof(tmp));
2411 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2412 session[s].tx_connect_speed = atol(tmp);
2413 }
2414 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2415 break;
2416 case 38: // rx connect speed
2417 if (n == 4)
2418 {
2419 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2420 }
2421 else
2422 {
2423 // AS5300s send connect speed as a string
2424 char tmp[30];
2425 memset(tmp, 0, sizeof(tmp));
2426 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2427 session[s].rx_connect_speed = atol(tmp);
2428 }
2429 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2430 break;
2431 case 25: // Physical Channel ID
2432 {
2433 uint32_t tmp = ntohl(*(uint32_t *) b);
2434 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2435 break;
2436 }
2437 case 29: // Proxy Authentication Type
2438 {
2439 uint16_t atype = ntohs(*(uint16_t *)b);
2440 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2441 break;
2442 }
2443 case 30: // Proxy Authentication Name
2444 {
2445 char authname[64];
2446 memset(authname, 0, sizeof(authname));
2447 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2448 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2449 authname);
2450 break;
2451 }
2452 case 31: // Proxy Authentication Challenge
2453 {
2454 LOG(4, s, t, " Proxy Auth Challenge\n");
2455 break;
2456 }
2457 case 32: // Proxy Authentication ID
2458 {
2459 uint16_t authid = ntohs(*(uint16_t *)(b));
2460 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2461 break;
2462 }
2463 case 33: // Proxy Authentication Response
2464 LOG(4, s, t, " Proxy Auth Response\n");
2465 break;
2466 case 27: // last sent lcp
2467 { // find magic number
2468 uint8_t *p = b, *e = p + n;
2469 while (p + 1 < e && p[1] && p + p[1] <= e)
2470 {
2471 if (*p == 5 && p[1] == 6) // Magic-Number
2472 amagic = ntohl(*(uint32_t *) (p + 2));
2473 else if (*p == 7) // Protocol-Field-Compression
2474 aflags |= SESSION_PFC;
2475 else if (*p == 8) // Address-and-Control-Field-Compression
2476 aflags |= SESSION_ACFC;
2477 p += p[1];
2478 }
2479 }
2480 break;
2481 case 28: // last recv lcp confreq
2482 break;
2483 case 26: // Initial Received LCP CONFREQ
2484 break;
2485 case 39: // seq required - we control it as an LNS anyway...
2486 break;
2487 case 36: // Random Vector
2488 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2489 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2490 if (n > sizeof(session[s].random_vector))
2491 n = sizeof(session[s].random_vector);
2492 memcpy(session[s].random_vector, b, n);
2493 session[s].random_vector_length = n;
2494 break;
2495 case 46: // ppp disconnect cause
2496 if (n >= 5)
2497 {
2498 uint16_t code = ntohs(*(uint16_t *) b);
2499 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2500 uint8_t dir = *(b + 4);
2501
2502 LOG(4, s, t, " PPP disconnect cause "
2503 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2504 code, proto, dir, n - 5, b + 5);
2505
2506 switch (code)
2507 {
2508 case 1: // admin disconnect
2509 disc_cause = TERM_ADMIN_RESET;
2510 disc_reason = "Administrative disconnect";
2511 break;
2512 case 3: // lcp terminate
2513 if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
2514 disc_cause = TERM_USER_REQUEST;
2515 disc_reason = "Normal disconnection";
2516 break;
2517 case 4: // compulsory encryption unavailable
2518 if (dir != 1) break; // 1=refused by peer, 2=local
2519 disc_cause = TERM_USER_ERROR;
2520 disc_reason = "Compulsory encryption refused";
2521 break;
2522 case 5: // lcp: fsm timeout
2523 disc_cause = TERM_PORT_ERROR;
2524 disc_reason = "LCP: FSM timeout";
2525 break;
2526 case 6: // lcp: no recognisable lcp packets received
2527 disc_cause = TERM_PORT_ERROR;
2528 disc_reason = "LCP: no recognisable LCP packets";
2529 break;
2530 case 7: // lcp: magic-no error (possibly looped back)
2531 disc_cause = TERM_PORT_ERROR;
2532 disc_reason = "LCP: magic-no error (possible loop)";
2533 break;
2534 case 8: // lcp: echo request timeout
2535 disc_cause = TERM_PORT_ERROR;
2536 disc_reason = "LCP: echo request timeout";
2537 break;
2538 case 13: // auth: fsm timeout
2539 disc_cause = TERM_SERVICE_UNAVAILABLE;
2540 disc_reason = "Authentication: FSM timeout";
2541 break;
2542 case 15: // auth: unacceptable auth protocol
2543 disc_cause = TERM_SERVICE_UNAVAILABLE;
2544 disc_reason = "Unacceptable authentication protocol";
2545 break;
2546 case 16: // auth: authentication failed
2547 disc_cause = TERM_SERVICE_UNAVAILABLE;
2548 disc_reason = "Authentication failed";
2549 break;
2550 case 17: // ncp: fsm timeout
2551 disc_cause = TERM_SERVICE_UNAVAILABLE;
2552 disc_reason = "NCP: FSM timeout";
2553 break;
2554 case 18: // ncp: no ncps available
2555 disc_cause = TERM_SERVICE_UNAVAILABLE;
2556 disc_reason = "NCP: no NCPs available";
2557 break;
2558 case 19: // ncp: failure to converge on acceptable address
2559 disc_cause = TERM_SERVICE_UNAVAILABLE;
2560 disc_reason = (dir == 1)
2561 ? "NCP: too many Configure-Naks received from peer"
2562 : "NCP: too many Configure-Naks sent to peer";
2563 break;
2564 case 20: // ncp: user not permitted to use any address
2565 disc_cause = TERM_SERVICE_UNAVAILABLE;
2566 disc_reason = (dir == 1)
2567 ? "NCP: local link address not acceptable to peer"
2568 : "NCP: remote link address not acceptable";
2569 break;
2570 }
2571 }
2572 break;
2573 default:
2574 {
2575 static char e[] = "unknown AVP 0xXXXX";
2576 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2577 fatal = flags;
2578 result = 2; // general error
2579 error = 8; // unknown mandatory AVP
2580 sprintf((msg = e) + 14, "%04x", mtype);
2581 continue; // next
2582 }
2583 }
2584 }
2585 // process message
2586 if (fatal & 0x80)
2587 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2588 else
2589 switch (message)
2590 {
2591 case 1: // SCCRQ - Start Control Connection Request
2592 tunnel[t].state = TUNNELOPENING;
2593 if (main_quit != QUIT_SHUTDOWN)
2594 {
2595 controlt *c = controlnew(2); // sending SCCRP
2596 control16(c, 2, version, 1); // protocol version
2597 control32(c, 3, 3, 1); // framing
2598 controls(c, 7, hostname, 1); // host name
2599 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2600 control16(c, 9, t, 1); // assigned tunnel
2601 controladd(c, 0, t); // send the resply
2602 }
2603 else
2604 {
2605 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2606 }
2607 break;
2608 case 2: // SCCRP
2609 tunnel[t].state = TUNNELOPEN;
2610 break;
2611 case 3: // SCCN
2612 tunnel[t].state = TUNNELOPEN;
2613 controlnull(t); // ack
2614 break;
2615 case 4: // StopCCN
2616 controlnull(t); // ack
2617 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2618 break;
2619 case 6: // HELLO
2620 controlnull(t); // simply ACK
2621 break;
2622 case 7: // OCRQ
2623 // TBA
2624 break;
2625 case 8: // OCRO
2626 // TBA
2627 break;
2628 case 9: // OCCN
2629 // TBA
2630 break;
2631 case 10: // ICRQ
2632 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2633 {
2634 controlt *c = controlnew(11); // ICRP
2635
2636 s = sessionfree;
2637 sessionfree = session[s].next;
2638 memset(&session[s], 0, sizeof(session[s]));
2639
2640 if (s > config->cluster_highest_sessionid)
2641 config->cluster_highest_sessionid = s;
2642
2643 session[s].opened = time_now;
2644 session[s].tunnel = t;
2645 session[s].far = asession;
2646 session[s].last_packet = time_now;
2647 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2648 control16(c, 14, s, 1); // assigned session
2649 controladd(c, asession, t); // send the reply
2650
2651 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2652 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2653
2654 session[s].ppp.phase = Establish;
2655 session[s].ppp.lcp = Starting;
2656
2657 STAT(session_created);
2658 break;
2659 }
2660
2661 {
2662 controlt *c = controlnew(14); // CDN
2663 if (!sessionfree)
2664 {
2665 STAT(session_overflow);
2666 LOG(1, 0, t, "No free sessions\n");
2667 control16(c, 1, 4, 0); // temporary lack of resources
2668 }
2669 else
2670 control16(c, 1, 2, 7); // shutting down, try another
2671
2672 controladd(c, asession, t); // send the message
2673 }
2674 return;
2675 case 11: // ICRP
2676 // TBA
2677 break;
2678 case 12: // ICCN
2679 if (amagic == 0) amagic = time_now;
2680 session[s].magic = amagic; // set magic number
2681 session[s].flags = aflags; // set flags received
2682 session[s].mru = PPPoE_MRU; // default
2683 controlnull(t); // ack
2684
2685 // start LCP
2686 sess_local[s].lcp_authtype = config->radius_authprefer;
2687 sess_local[s].ppp_mru = MRU;
2688
2689 // Set multilink options before sending initial LCP packet
2690 sess_local[s].mp_mrru = 1614;
2691 sess_local[s].mp_epdis = config->bind_address ? config->bind_address : my_address;
2692
2693 sendlcp(s, t);
2694 change_state(s, lcp, RequestSent);
2695 break;
2696
2697 case 14: // CDN
2698 controlnull(t); // ack
2699 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
2700 break;
2701 case 0xFFFF:
2702 LOG(1, s, t, "Missing message type\n");
2703 break;
2704 default:
2705 STAT(tunnel_rx_errors);
2706 if (mandatory)
2707 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2708 else
2709 LOG(1, s, t, "Unknown message type %d\n", message);
2710 break;
2711 }
2712 if (chapresponse) free(chapresponse);
2713 cluster_send_tunnel(t);
2714 }
2715 else
2716 {
2717 LOG(4, s, t, " Got a ZLB ack\n");
2718 }
2719 }
2720 else
2721 { // data
2722 uint16_t proto;
2723
2724 LOG_HEX(5, "Receive Tunnel Data", p, l);
2725 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2726 { // HDLC address header, discard
2727 p += 2;
2728 l -= 2;
2729 }
2730 if (l < 2)
2731 {
2732 LOG(1, s, t, "Short ppp length %d\n", l);
2733 STAT(tunnel_rx_errors);
2734 return;
2735 }
2736 if (*p & 1)
2737 {
2738 proto = *p++;
2739 l--;
2740 }
2741 else
2742 {
2743 proto = ntohs(*(uint16_t *) p);
2744 p += 2;
2745 l -= 2;
2746 }
2747
2748 if (s && !session[s].opened) // Is something wrong??
2749 {
2750 if (!config->cluster_iam_master)
2751 {
2752 // Pass it off to the master to deal with..
2753 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2754 return;
2755 }
2756
2757
2758 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2759 STAT(tunnel_rx_errors);
2760 return;
2761 }
2762
2763 if (proto == PPPPAP)
2764 {
2765 session[s].last_packet = time_now;
2766 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2767 processpap(s, t, p, l);
2768 }
2769 else if (proto == PPPCHAP)
2770 {
2771 session[s].last_packet = time_now;
2772 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2773 processchap(s, t, p, l);
2774 }
2775 else if (proto == PPPLCP)
2776 {
2777 session[s].last_packet = time_now;
2778 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2779 processlcp(s, t, p, l);
2780 }
2781 else if (proto == PPPIPCP)
2782 {
2783 session[s].last_packet = time_now;
2784 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2785 processipcp(s, t, p, l);
2786 }
2787 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2788 {
2789 session[s].last_packet = time_now;
2790 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2791 processipv6cp(s, t, p, l);
2792 }
2793 else if (proto == PPPCCP)
2794 {
2795 session[s].last_packet = time_now;
2796 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2797 processccp(s, t, p, l);
2798 }
2799 else if (proto == PPPIP)
2800 {
2801 if (session[s].die)
2802 {
2803 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2804 return; // closing session, PPP not processed
2805 }
2806
2807 session[s].last_packet = time_now;
2808 if (session[s].walled_garden && !config->cluster_iam_master)
2809 {
2810 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2811 return;
2812 }
2813
2814 processipin(s, t, p, l);
2815 }
2816 else if (proto == PPPMP)
2817 {
2818 if (session[s].die)
2819 {
2820 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2821 return; // closing session, PPP not processed
2822 }
2823
2824 session[s].last_packet = time_now;
2825 if (session[s].walled_garden && !config->cluster_iam_master)
2826 {
2827 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2828 return;
2829 }
2830
2831 processmpin(s, t, p, l);
2832 }
2833 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2834 {
2835 if (session[s].die)
2836 {
2837 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2838 return; // closing session, PPP not processed
2839 }
2840
2841 session[s].last_packet = time_now;
2842 if (session[s].walled_garden && !config->cluster_iam_master)
2843 {
2844 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2845 return;
2846 }
2847
2848 processipv6in(s, t, p, l);
2849 }
2850 else if (session[s].ppp.lcp == Opened)
2851 {
2852 session[s].last_packet = time_now;
2853 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2854 protoreject(s, t, p, l, proto);
2855 }
2856 else
2857 {
2858 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2859 proto, ppp_state(session[s].ppp.lcp));
2860 }
2861 }
2862 }
2863
2864 // read and process packet on tun
2865 static void processtun(uint8_t * buf, int len)
2866 {
2867 LOG_HEX(5, "Receive TUN Data", buf, len);
2868 STAT(tun_rx_packets);
2869 INC_STAT(tun_rx_bytes, len);
2870
2871 CSTAT(processtun);
2872
2873 eth_rx_pkt++;
2874 eth_rx += len;
2875 if (len < 22)
2876 {
2877 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2878 STAT(tun_rx_errors);
2879 return;
2880 }
2881
2882 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2883 processipout(buf, len);
2884 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2885 && config->ipv6_prefix.s6_addr[0])
2886 processipv6out(buf, len);
2887
2888 // Else discard.
2889 }
2890
2891 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2892 // that we look at the whole of the tunnel, radius and session tables
2893 // every second
2894 static void regular_cleanups(double period)
2895 {
2896 // Next tunnel, radius and session to check for actions on.
2897 static tunnelidt t = 0;
2898 static int r = 0;
2899 static sessionidt s = 0;
2900
2901 int t_actions = 0;
2902 int r_actions = 0;
2903 int s_actions = 0;
2904
2905 int t_slice;
2906 int r_slice;
2907 int s_slice;
2908
2909 int i;
2910 int a;
2911
2912 // divide up tables into slices based on the last run
2913 t_slice = config->cluster_highest_tunnelid * period;
2914 r_slice = (MAXRADIUS - 1) * period;
2915 s_slice = config->cluster_highest_sessionid * period;
2916
2917 if (t_slice < 1)
2918 t_slice = 1;
2919 else if (t_slice > config->cluster_highest_tunnelid)
2920 t_slice = config->cluster_highest_tunnelid;
2921
2922 if (r_slice < 1)
2923 r_slice = 1;
2924 else if (r_slice > (MAXRADIUS - 1))
2925 r_slice = MAXRADIUS - 1;
2926
2927 if (s_slice < 1)
2928 s_slice = 1;
2929 else if (s_slice > config->cluster_highest_sessionid)
2930 s_slice = config->cluster_highest_sessionid;
2931
2932 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2933
2934 for (i = 0; i < t_slice; i++)
2935 {
2936 t++;
2937 if (t > config->cluster_highest_tunnelid)
2938 t = 1;
2939
2940 // check for expired tunnels
2941 if (tunnel[t].die && tunnel[t].die <= TIME)
2942 {
2943 STAT(tunnel_timeout);
2944 tunnelkill(t, "Expired");
2945 t_actions++;
2946 continue;
2947 }
2948 // check for message resend
2949 if (tunnel[t].retry && tunnel[t].controlc)
2950 {
2951 // resend pending messages as timeout on reply
2952 if (tunnel[t].retry <= TIME)
2953 {
2954 controlt *c = tunnel[t].controls;
2955 uint8_t w = tunnel[t].window;
2956 tunnel[t].try++; // another try
2957 if (tunnel[t].try > 5)
2958 tunnelkill(t, "Timeout on control message"); // game over
2959 else
2960 while (c && w--)
2961 {
2962 tunnelsend(c->buf, c->length, t);
2963 c = c->next;
2964 }
2965
2966 t_actions++;
2967 }
2968 }
2969 // Send hello
2970 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2971 {
2972 controlt *c = controlnew(6); // sending HELLO
2973 controladd(c, 0, t); // send the message
2974 LOG(3, 0, t, "Sending HELLO message\n");
2975 t_actions++;
2976 }
2977
2978 // Check for tunnel changes requested from the CLI
2979 if ((a = cli_tunnel_actions[t].action))
2980 {
2981 cli_tunnel_actions[t].action = 0;
2982 if (a & CLI_TUN_KILL)
2983 {
2984 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2985 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2986 t_actions++;
2987 }
2988 }
2989 }
2990
2991 for (i = 0; i < r_slice; i++)
2992 {
2993 r++;
2994 if (r >= MAXRADIUS)
2995 r = 1;
2996
2997 if (!radius[r].state)
2998 continue;
2999
3000 if (radius[r].retry <= TIME)
3001 {
3002 radiusretry(r);
3003 r_actions++;
3004 }
3005 }
3006
3007 for (i = 0; i < s_slice; i++)
3008 {
3009 s++;
3010 if (s > config->cluster_highest_sessionid)
3011 s = 1;
3012
3013 if (!session[s].opened) // Session isn't in use
3014 continue;
3015
3016 // check for expired sessions
3017 if (session[s].die)
3018 {
3019 if (session[s].die <= TIME)
3020 {
3021 sessionkill(s, "Expired");
3022 s_actions++;
3023 }
3024 continue;
3025 }
3026
3027 // check for timed out sessions
3028 if (session[s].timeout)
3029 {
3030 bundleidt bid = session[s].bundle;
3031 if (bid)
3032 {
3033 clockt curr_time = time_now;
3034 if (curr_time - bundle[bid].last_check >= 1)
3035 {
3036 bundle[bid].online_time += (curr_time-bundle[bid].last_check)*bundle[bid].num_of_links;
3037 bundle[bid].last_check = curr_time;
3038 if (bundle[bid].online_time >= session[s].timeout)
3039 {
3040 int ses;
3041 for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
3042 {
3043 sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3044 s_actions++;
3045 continue;
3046 }
3047 }
3048 }
3049 }
3050 else if (session[s].timeout <= time_now - session[s].opened)
3051 {
3052 sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3053 s_actions++;
3054 continue;
3055 }
3056 }
3057
3058 // PPP timeouts
3059 if (sess_local[s].lcp.restart <= time_now)
3060 {
3061 int next_state = session[s].ppp.lcp;
3062 switch (session[s].ppp.lcp)
3063 {
3064 case RequestSent:
3065 case AckReceived:
3066 next_state = RequestSent;
3067
3068 case AckSent:
3069 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
3070 {
3071 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
3072 sendlcp(s, session[s].tunnel);
3073 change_state(s, lcp, next_state);
3074 }
3075 else
3076 {
3077 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3078 STAT(session_timeout);
3079 }
3080
3081 s_actions++;
3082 }
3083
3084 if (session[s].die)
3085 continue;
3086 }
3087
3088 if (sess_local[s].ipcp.restart <= time_now)
3089 {
3090 int next_state = session[s].ppp.ipcp;
3091 switch (session[s].ppp.ipcp)
3092 {
3093 case RequestSent:
3094 case AckReceived:
3095 next_state = RequestSent;
3096
3097 case AckSent:
3098 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
3099 {
3100 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
3101 sendipcp(s, session[s].tunnel);
3102 change_state(s, ipcp, next_state);
3103 }
3104 else
3105 {
3106 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3107 STAT(session_timeout);
3108 }
3109
3110 s_actions++;
3111 }
3112
3113 if (session[s].die)
3114 continue;
3115 }
3116
3117 if (sess_local[s].ipv6cp.restart <= time_now)
3118 {
3119 int next_state = session[s].ppp.ipv6cp;
3120 switch (session[s].ppp.ipv6cp)
3121 {
3122 case RequestSent:
3123 case AckReceived:
3124 next_state = RequestSent;
3125
3126 case AckSent:
3127 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
3128 {
3129 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
3130 sendipv6cp(s, session[s].tunnel);
3131 change_state(s, ipv6cp, next_state);
3132 }
3133 else
3134 {
3135 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
3136 change_state(s, ipv6cp, Stopped);
3137 }
3138
3139 s_actions++;
3140 }
3141 }
3142
3143 if (sess_local[s].ccp.restart <= time_now)
3144 {
3145 int next_state = session[s].ppp.ccp;
3146 switch (session[s].ppp.ccp)
3147 {
3148 case RequestSent:
3149 case AckReceived:
3150 next_state = RequestSent;
3151
3152 case AckSent:
3153 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
3154 {
3155 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
3156 sendccp(s, session[s].tunnel);
3157 change_state(s, ccp, next_state);
3158 }
3159 else
3160 {
3161 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
3162 change_state(s, ccp, Stopped);
3163 }
3164
3165 s_actions++;
3166 }
3167 }
3168
3169 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
3170 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
3171 {
3172 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3173 STAT(session_timeout);
3174 s_actions++;
3175 continue;
3176 }
3177
3178 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
3179 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
3180 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
3181 {
3182 uint8_t b[MAXETHER];
3183
3184 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
3185 if (!q) continue;
3186
3187 *q = EchoReq;
3188 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3189 *(uint16_t *)(q + 2) = htons(8); // Length
3190 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3191
3192 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3193 (int)(time_now - session[s].last_packet));
3194 tunnelsend(b, 24, session[s].tunnel); // send it
3195 sess_local[s].last_echo = time_now;
3196 s_actions++;
3197 }
3198
3199 // Check for actions requested from the CLI
3200 if ((a = cli_session_actions[s].action))
3201 {
3202 int send = 0;
3203
3204 cli_session_actions[s].action = 0;
3205 if (a & CLI_SESS_KILL)
3206 {
3207 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3208 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3209 a = 0; // dead, no need to check for other actions
3210 s_actions++;
3211 }
3212
3213 if (a & CLI_SESS_NOSNOOP)
3214 {
3215 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3216 session[s].snoop_ip = 0;
3217 session[s].snoop_port = 0;
3218 s_actions++;
3219 send++;
3220 }
3221 else if (a & CLI_SESS_SNOOP)
3222 {
3223 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
3224 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3225 cli_session_actions[s].snoop_port);
3226
3227 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3228 session[s].snoop_port = cli_session_actions[s].snoop_port;
3229 s_actions++;
3230 send++;
3231 }
3232
3233 if (a & CLI_SESS_NOTHROTTLE)
3234 {
3235 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3236 throttle_session(s, 0, 0);
3237 s_actions++;
3238 send++;
3239 }
3240 else if (a & CLI_SESS_THROTTLE)
3241 {
3242 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3243 cli_session_actions[s].throttle_in,
3244 cli_session_actions[s].throttle_out);
3245
3246 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3247 s_actions++;
3248 send++;
3249 }
3250
3251 if (a & CLI_SESS_NOFILTER)
3252 {
3253 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3254 filter_session(s, 0, 0);
3255 s_actions++;
3256 send++;
3257 }
3258 else if (a & CLI_SESS_FILTER)
3259 {
3260 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3261 cli_session_actions[s].filter_in,
3262 cli_session_actions[s].filter_out);
3263
3264 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3265 s_actions++;
3266 send++;
3267 }
3268
3269 if (send)
3270 cluster_send_session(s);
3271 }
3272
3273 // RADIUS interim accounting
3274 if (config->radius_accounting && config->radius_interim > 0
3275 && session[s].ip && !session[s].walled_garden
3276 && !sess_local[s].radius // RADIUS already in progress
3277 && time_now - sess_local[s].last_interim >= config->radius_interim)
3278 {
3279 int rad = radiusnew(s);
3280 if (!rad)
3281 {
3282 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3283 STAT(radius_overflow);
3284 continue;
3285 }
3286
3287 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3288 session[s].user, session[s].unique_id);
3289
3290 radiussend(rad, RADIUSINTERIM);
3291 sess_local[s].last_interim = time_now;
3292 s_actions++;
3293 }
3294 }
3295
3296 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3297 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3298 }
3299
3300 //
3301 // Are we in the middle of a tunnel update, or radius
3302 // requests??
3303 //
3304 static int still_busy(void)
3305 {
3306 int i;
3307 static clockt last_talked = 0;
3308 static clockt start_busy_wait = 0;
3309
3310 if (!config->cluster_iam_master)
3311 {
3312 #ifdef BGP
3313 static time_t stopped_bgp = 0;
3314 if (bgp_configured)
3315 {
3316 if (!stopped_bgp)
3317 {
3318 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3319
3320 for (i = 0; i < BGP_NUM_PEERS; i++)
3321 if (bgp_peers[i].state == Established)
3322 bgp_stop(&bgp_peers[i]);
3323
3324 stopped_bgp = time_now;
3325
3326 // we don't want to become master
3327 cluster_send_ping(0);
3328
3329 return 1;
3330 }
3331
3332 if (time_now < (stopped_bgp + QUIT_DELAY))
3333 return 1;
3334 }
3335 #endif /* BGP */
3336
3337 return 0;
3338 }
3339
3340 if (main_quit == QUIT_SHUTDOWN)
3341 {
3342 static int dropped = 0;
3343 if (!dropped)
3344 {
3345 int i;
3346
3347 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3348 for (i = 1; i < MAXTUNNEL; i++)
3349 if (tunnel[i].ip || tunnel[i].state)
3350 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3351
3352 dropped = 1;
3353 }
3354 }
3355
3356 if (start_busy_wait == 0)
3357 start_busy_wait = TIME;
3358
3359 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3360 {
3361 if (!tunnel[i].controlc)
3362 continue;
3363
3364 if (last_talked != TIME)
3365 {
3366 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3367 last_talked = TIME;
3368 }
3369 return 1;
3370 }
3371
3372 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3373 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3374 {
3375 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3376 return 0;
3377 }
3378
3379 for (i = 1; i < MAXRADIUS; i++)
3380 {
3381 if (radius[i].state == RADIUSNULL)
3382 continue;
3383 if (radius[i].state == RADIUSWAIT)
3384 continue;
3385
3386 if (last_talked != TIME)
3387 {
3388 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3389 last_talked = TIME;
3390 }
3391 return 1;
3392 }
3393
3394 return 0;
3395 }
3396
3397 #ifdef HAVE_EPOLL
3398 # include <sys/epoll.h>
3399 #else
3400 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3401 # include "fake_epoll.h"
3402 #endif
3403
3404 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3405 #define BASE_FDS 6
3406
3407 // additional polled fds
3408 #ifdef BGP
3409 # define EXTRA_FDS BGP_NUM_PEERS
3410 #else
3411 # define EXTRA_FDS 0
3412 #endif
3413
3414 // main loop - gets packets on tun or udp and processes them
3415 static void mainloop(void)
3416 {
3417 int i;
3418 uint8_t buf[65536];
3419 clockt next_cluster_ping = 0; // send initial ping immediately
3420 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3421 int maxevent = sizeof(events)/sizeof(*events);
3422
3423 if ((epollfd = epoll_create(maxevent)) < 0)
3424 {
3425 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3426 exit(1);
3427 }
3428
3429 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3430 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3431
3432 /* setup our fds to poll for input */
3433 {
3434 static struct event_data d[BASE_FDS];
3435 struct epoll_event e;
3436
3437 e.events = EPOLLIN;
3438 i = 0;
3439
3440 if (clifd >= 0)
3441 {
3442 d[i].type = FD_TYPE_CLI;
3443 e.data.ptr = &d[i++];
3444 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3445 }
3446
3447 d[i].type = FD_TYPE_CLUSTER;
3448 e.data.ptr = &d[i++];
3449 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3450
3451 d[i].type = FD_TYPE_TUN;
3452 e.data.ptr = &d[i++];
3453 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3454
3455 d[i].type = FD_TYPE_UDP;
3456 e.data.ptr = &d[i++];
3457 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3458
3459 d[i].type = FD_TYPE_CONTROL;
3460 e.data.ptr = &d[i++];
3461 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3462
3463 d[i].type = FD_TYPE_DAE;
3464 e.data.ptr = &d[i++];
3465 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3466 }
3467
3468 #ifdef BGP
3469 signal(SIGPIPE, SIG_IGN);
3470 bgp_setup(config->as_number);
3471 if (config->bind_address)
3472 bgp_add_route(config->bind_address, 0xffffffff);
3473
3474 for (i = 0; i < BGP_NUM_PEERS; i++)
3475 {
3476 if (config->neighbour[i].name[0])
3477 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3478 config->neighbour[i].as, config->neighbour[i].keepalive,
3479 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3480 }
3481 #endif /* BGP */
3482
3483 while (!main_quit || still_busy())
3484 {
3485 int more = 0;
3486 int n;
3487
3488
3489 if (main_reload)
3490 {
3491 main_reload = 0;
3492 read_config_file();
3493 config->reload_config++;
3494 }
3495
3496 if (config->reload_config)
3497 {
3498 config->reload_config = 0;
3499 update_config();
3500 }
3501
3502 #ifdef BGP
3503 bgp_set_poll();
3504 #endif /* BGP */
3505
3506 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3507 STAT(select_called);
3508
3509 TIME = now(NULL);
3510 if (n < 0)
3511 {
3512 if (errno == EINTR ||
3513 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3514 continue;
3515
3516 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3517 break; // exit
3518 }
3519
3520 if (n)
3521 {
3522 struct sockaddr_in addr;
3523 struct in_addr local;
3524 socklen_t alen;
3525 int c, s;
3526 int udp_ready = 0;
3527 int tun_ready = 0;
3528 int cluster_ready = 0;
3529 int udp_pkts = 0;
3530 int tun_pkts = 0;
3531 int cluster_pkts = 0;
3532 #ifdef BGP
3533 uint32_t bgp_events[BGP_NUM_PEERS];
3534 memset(bgp_events, 0, sizeof(bgp_events));
3535 #endif /* BGP */
3536
3537 for (c = n, i = 0; i < c; i++)
3538 {
3539 struct event_data *d = events[i].data.ptr;
3540
3541 switch (d->type)
3542 {
3543 case FD_TYPE_CLI: // CLI connections
3544 {
3545 int cli;
3546
3547 alen = sizeof(addr);
3548 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3549 {
3550 cli_do(cli);
3551 close(cli);
3552 }
3553 else
3554 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3555
3556 n--;
3557 break;
3558 }
3559
3560 // these are handled below, with multiple interleaved reads
3561 case FD_TYPE_CLUSTER: cluster_ready++; break;
3562 case FD_TYPE_TUN: tun_ready++; break;
3563 case FD_TYPE_UDP: udp_ready++; break;
3564
3565 case FD_TYPE_CONTROL: // nsctl commands
3566 alen = sizeof(addr);
3567 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3568 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3569 n--;
3570 break;
3571
3572 case FD_TYPE_DAE: // DAE requests
3573 alen = sizeof(addr);
3574 s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3575 if (s > 0) processdae(buf, s, &addr, alen, &local);
3576 n--;
3577 break;
3578
3579 case FD_TYPE_RADIUS: // RADIUS response
3580 alen = sizeof(addr);
3581 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3582 if (s >= 0 && config->cluster_iam_master)
3583 {
3584 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3585 addr.sin_addr.s_addr == config->radiusserver[1])
3586 processrad(buf, s, d->index);
3587 else
3588 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3589 fmtaddr(addr.sin_addr.s_addr, 0));
3590 }
3591
3592 n--;
3593 break;
3594
3595 #ifdef BGP
3596 case FD_TYPE_BGP:
3597 bgp_events[d->index] = events[i].events;
3598 n--;
3599 break;
3600 #endif /* BGP */
3601
3602 default:
3603 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3604 }
3605 }
3606
3607 #ifdef BGP
3608 bgp_process(bgp_events);
3609 #endif /* BGP */
3610
3611 for (c = 0; n && c < config->multi_read_count; c++)
3612 {
3613 // L2TP
3614 if (udp_ready)
3615 {
3616 alen = sizeof(addr);
3617 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3618 {
3619 processudp(buf, s, &addr);
3620 udp_pkts++;
3621 }
3622 else
3623 {
3624 udp_ready = 0;
3625 n--;
3626 }
3627 }
3628
3629 // incoming IP
3630 if (tun_ready)
3631 {
3632 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3633 {
3634 processtun(buf, s);
3635 tun_pkts++;
3636 }
3637 else
3638 {
3639 tun_ready = 0;
3640 n--;
3641 }
3642 }
3643
3644 // cluster
3645 if (cluster_ready)
3646 {
3647 alen = sizeof(addr);
3648 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3649 {
3650 processcluster(buf, s, addr.sin_addr.s_addr);
3651 cluster_pkts++;
3652 }
3653 else
3654 {
3655 cluster_ready = 0;
3656 n--;
3657 }
3658 }
3659 }
3660
3661 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3662 STAT(multi_read_used);
3663
3664 if (c >= config->multi_read_count)
3665 {
3666 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3667 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3668
3669 STAT(multi_read_exceeded);
3670 more++;
3671 }
3672 }
3673
3674 if (time_changed)
3675 {
3676 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3677
3678 // Log current traffic stats
3679 snprintf(config->bandwidth, sizeof(config->bandwidth),
3680 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3681 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3682 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3683 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3684
3685 udp_tx = udp_rx = 0;
3686 udp_rx_pkt = eth_rx_pkt = 0;
3687 eth_tx = eth_rx = 0;
3688 time_changed = 0;
3689
3690 if (config->dump_speed)
3691 printf("%s\n", config->bandwidth);
3692
3693 // Update the internal time counter
3694 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3695
3696 {
3697 // Run timer hooks
3698 struct param_timer p = { time_now };
3699 run_plugins(PLUGIN_TIMER, &p);
3700 }
3701 }
3702
3703 // Runs on every machine (master and slaves).
3704 if (next_cluster_ping <= TIME)
3705 {
3706 // Check to see which of the cluster is still alive..
3707
3708 cluster_send_ping(basetime); // Only does anything if we're a slave
3709 cluster_check_master(); // ditto.
3710
3711 cluster_heartbeat(); // Only does anything if we're a master.
3712 cluster_check_slaves(); // ditto.
3713
3714 master_update_counts(); // If we're a slave, send our byte counters to our master.
3715
3716 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3717 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3718 else
3719 next_cluster_ping = TIME + config->cluster_hb_interval;
3720 }
3721
3722 if (!config->cluster_iam_master)
3723 continue;
3724
3725 // Run token bucket filtering queue..
3726 // Only run it every 1/10th of a second.
3727 {
3728 static clockt last_run = 0;
3729 if (last_run != TIME)
3730 {
3731 last_run = TIME;
3732 tbf_run_timer();
3733 }
3734 }
3735
3736 // Handle timeouts, retries etc.
3737 {
3738 static double last_clean = 0;
3739 double this_clean;
3740 double diff;
3741
3742 TIME = now(&this_clean);
3743 diff = this_clean - last_clean;
3744
3745 // Run during idle time (after we've handled
3746 // all incoming packets) or every 1/10th sec
3747 if (!more || diff > 0.1)
3748 {
3749 regular_cleanups(diff);
3750 last_clean = this_clean;
3751 }
3752 }
3753
3754 if (*config->accounting_dir)
3755 {
3756 static clockt next_acct = 0;
3757 static clockt next_shut_acct = 0;
3758
3759 if (next_acct <= TIME)
3760 {
3761 // Dump accounting data
3762 next_acct = TIME + ACCT_TIME;
3763 next_shut_acct = TIME + ACCT_SHUT_TIME;
3764 dump_acct_info(1);
3765 }
3766 else if (next_shut_acct <= TIME)
3767 {
3768 // Dump accounting data for shutdown sessions
3769 next_shut_acct = TIME + ACCT_SHUT_TIME;
3770 if (shut_acct_n)
3771 dump_acct_info(0);
3772 }
3773 }
3774 }
3775
3776 // Are we the master and shutting down??
3777 if (config->cluster_iam_master)
3778 cluster_heartbeat(); // Flush any queued changes..
3779
3780 // Ok. Notify everyone we're shutting down. If we're
3781 // the master, this will force an election.
3782 cluster_send_ping(0);
3783
3784 //
3785 // Important!!! We MUST not process any packets past this point!
3786 LOG(1, 0, 0, "Shutdown complete\n");
3787 }
3788
3789 static void stripdomain(char *host)
3790 {
3791 char *p;
3792
3793 if ((p = strchr(host, '.')))
3794 {
3795 char *domain = 0;
3796 char _domain[1024];
3797
3798 // strip off domain
3799 FILE *resolv = fopen("/etc/resolv.conf", "r");
3800 if (resolv)
3801 {
3802 char buf[1024];
3803 char *b;
3804
3805 while (fgets(buf, sizeof(buf), resolv))
3806 {
3807 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3808 continue;
3809
3810 if (!isspace(buf[6]))
3811 continue;
3812
3813 b = buf + 7;
3814 while (isspace(*b)) b++;
3815
3816 if (*b)
3817 {
3818 char *d = b;
3819 while (*b && !isspace(*b)) b++;
3820 *b = 0;
3821 if (buf[0] == 'd') // domain is canonical
3822 {
3823 domain = d;
3824 break;
3825 }
3826
3827 // first search line
3828 if (!domain)
3829 {
3830 // hold, may be subsequent domain line
3831 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3832 domain = _domain;
3833 }
3834 }
3835 }
3836
3837 fclose(resolv);
3838 }
3839
3840 if (domain)
3841 {
3842 int hl = strlen(host);
3843 int dl = strlen(domain);
3844 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3845 host[hl -dl - 1] = 0;
3846 }
3847 else
3848 {
3849 *p = 0; // everything after first dot
3850 }
3851 }
3852 }
3853
3854 // Init data structures
3855 static void initdata(int optdebug, char *optconfig)
3856 {
3857 int i;
3858
3859 if (!(config = shared_malloc(sizeof(configt))))
3860 {
3861 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3862 exit(1);
3863 }
3864
3865 memset(config, 0, sizeof(configt));
3866 time(&config->start_time);
3867 strncpy(config->config_file, optconfig, strlen(optconfig));
3868 config->debug = optdebug;
3869 config->num_tbfs = MAXTBFS;
3870 config->rl_rate = 28; // 28kbps
3871 config->cluster_mcast_ttl = 1;
3872 config->cluster_master_min_adv = 1;
3873 config->ppp_restart_time = 3;
3874 config->ppp_max_configure = 10;
3875 config->ppp_max_failure = 5;
3876 strcpy(config->random_device, RANDOMDEVICE);
3877
3878 log_stream = stderr;
3879
3880 #ifdef RINGBUFFER
3881 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3882 {
3883 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3884 exit(1);
3885 }
3886 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3887 #endif
3888
3889 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3890 {
3891 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3892 exit(1);
3893 }
3894 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3895 {
3896 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3897 exit(1);
3898 }
3899 if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
3900 {
3901 LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
3902 exit(1);
3903 }
3904 if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
3905 {
3906 LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
3907 exit(1);
3908 }
3909 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3910 {
3911 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3912 exit(1);
3913 }
3914
3915 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3916 {
3917 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3918 exit(1);
3919 }
3920
3921 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3922 {
3923 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3924 exit(1);
3925 }
3926
3927 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3928 {
3929 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3930 exit(1);
3931 }
3932
3933 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3934 {
3935 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3936 exit(1);
3937 }
3938 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3939
3940 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3941 {
3942 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3943 exit(1);
3944 }
3945 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3946
3947 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3948 {
3949 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3950 exit(1);
3951 }
3952 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3953
3954 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3955 memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
3956 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3957 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3958 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3959
3960 // Put all the sessions on the free list marked as undefined.
3961 for (i = 1; i < MAXSESSION; i++)
3962 {
3963 session[i].next = i + 1;
3964 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3965 }
3966 session[MAXSESSION - 1].next = 0;
3967 sessionfree = 1;
3968
3969 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3970 for (i = 1; i < MAXTUNNEL; i++)
3971 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3972
3973 for (i = 1; i < MAXBUNDLE; i++) {
3974 bundle[i].state = BUNDLEUNDEF;
3975 }
3976
3977 if (!*hostname)
3978 {
3979 // Grab my hostname unless it's been specified
3980 gethostname(hostname, sizeof(hostname));
3981 stripdomain(hostname);
3982 }
3983
3984 _statistics->start_time = _statistics->last_reset = time(NULL);
3985
3986 #ifdef BGP
3987 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3988 {
3989 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3990 exit(1);
3991 }
3992 #endif /* BGP */
3993 }
3994
3995 static int assign_ip_address(sessionidt s)
3996 {
3997 uint32_t i;
3998 int best = -1;
3999 time_t best_time = time_now;
4000 char *u = session[s].user;
4001 char reuse = 0;
4002
4003
4004 CSTAT(assign_ip_address);
4005
4006 for (i = 1; i < ip_pool_size; i++)
4007 {
4008 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
4009 continue;
4010
4011 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
4012 {
4013 best = i;
4014 reuse = 1;
4015 break;
4016 }
4017
4018 if (ip_address_pool[i].last < best_time)
4019 {
4020 best = i;
4021 if (!(best_time = ip_address_pool[i].last))
4022 break; // never used, grab this one
4023 }
4024 }
4025
4026 if (best < 0)
4027 {
4028 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
4029 return 0;
4030 }
4031
4032 session[s].ip = ip_address_pool[best].address;
4033 session[s].ip_pool_index = best;
4034 ip_address_pool[best].assigned = 1;
4035 ip_address_pool[best].last = time_now;
4036 ip_address_pool[best].session = s;
4037 if (session[s].walled_garden)
4038 /* Don't track addresses of users in walled garden (note: this
4039 means that their address isn't "sticky" even if they get
4040 un-gardened). */
4041 ip_address_pool[best].user[0] = 0;
4042 else
4043 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
4044
4045 STAT(ip_allocated);
4046 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
4047 reuse ? "Reusing" : "Allocating", best);
4048
4049 return 1;
4050 }
4051
4052 static void free_ip_address(sessionidt s)
4053 {
4054 int i = session[s].ip_pool_index;
4055
4056
4057 CSTAT(free_ip_address);
4058
4059 if (!session[s].ip)
4060 return; // what the?
4061
4062 if (i < 0) // Is this actually part of the ip pool?
4063 i = 0;
4064
4065 STAT(ip_freed);
4066 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
4067 session[s].ip = 0;
4068 ip_address_pool[i].assigned = 0;
4069 ip_address_pool[i].session = 0;
4070 ip_address_pool[i].last = time_now;
4071 }
4072
4073 //
4074 // Fsck the address pool against the session table.
4075 // Normally only called when we become a master.
4076 //
4077 // This isn't perfect: We aren't keep tracking of which
4078 // users used to have an IP address.
4079 //
4080 void rebuild_address_pool(void)
4081 {
4082 int i;
4083
4084 //
4085 // Zero the IP pool allocation, and build
4086 // a map from IP address to pool index.
4087 for (i = 1; i < MAXIPPOOL; ++i)
4088 {
4089 ip_address_pool[i].assigned = 0;
4090 ip_address_pool[i].session = 0;
4091 if (!ip_address_pool[i].address)
4092 continue;
4093
4094 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
4095 }
4096
4097 for (i = 0; i < MAXSESSION; ++i)
4098 {
4099 int ipid;
4100 if (!(session[i].opened && session[i].ip))
4101 continue;
4102
4103 ipid = - lookup_ipmap(htonl(session[i].ip));
4104
4105 if (session[i].ip_pool_index < 0)
4106 {
4107 // Not allocated out of the pool.
4108 if (ipid < 1) // Not found in the pool either? good.
4109 continue;
4110
4111 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
4112 i, fmtaddr(session[i].ip, 0), ipid);
4113
4114 // Fall through and process it as part of the pool.
4115 }
4116
4117
4118 if (ipid > MAXIPPOOL || ipid < 0)
4119 {
4120 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
4121 ipid = -1;
4122 session[i].ip_pool_index = ipid;
4123 continue;
4124 }
4125
4126 ip_address_pool[ipid].assigned = 1;
4127 ip_address_pool[ipid].session = i;
4128 ip_address_pool[ipid].last = time_now;
4129 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
4130 session[i].ip_pool_index = ipid;
4131 cache_ipmap(session[i].ip, i); // Fix the ip map.
4132 }
4133 }
4134
4135 //
4136 // Fix the address pool to match a changed session.
4137 // (usually when the master sends us an update).
4138 static void fix_address_pool(int sid)
4139 {
4140 int ipid;
4141
4142 ipid = session[sid].ip_pool_index;
4143
4144 if (ipid > ip_pool_size)
4145 return; // Ignore it. rebuild_address_pool will fix it up.
4146
4147 if (ip_address_pool[ipid].address != session[sid].ip)
4148 return; // Just ignore it. rebuild_address_pool will take care of it.
4149
4150 ip_address_pool[ipid].assigned = 1;
4151 ip_address_pool[ipid].session = sid;
4152 ip_address_pool[ipid].last = time_now;
4153 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
4154 }
4155
4156 //
4157 // Add a block of addresses to the IP pool to hand out.
4158 //
4159 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
4160 {
4161 int i;
4162 if (mask == 0)
4163 mask = 0xffffffff; // Host route only.
4164
4165 addr &= mask;
4166
4167 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
4168 return ;
4169
4170 for (i = addr ;(i & mask) == addr; ++i)
4171 {
4172 if ((i & 0xff) == 0 || (i&0xff) == 255)
4173 continue; // Skip 0 and broadcast addresses.
4174
4175 ip_address_pool[ip_pool_size].address = i;
4176 ip_address_pool[ip_pool_size].assigned = 0;
4177 ++ip_pool_size;
4178 if (ip_pool_size >= MAXIPPOOL)
4179 {
4180 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
4181 return;
4182 }
4183 }
4184 }
4185
4186 // Initialize the IP address pool
4187 static void initippool()
4188 {
4189 FILE *f;
4190 char *p;
4191 char buf[4096];
4192 memset(ip_address_pool, 0, sizeof(ip_address_pool));
4193
4194 if (!(f = fopen(IPPOOLFILE, "r")))
4195 {
4196 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
4197 exit(1);
4198 }
4199
4200 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4201 {
4202 char *pool = buf;
4203 buf[4095] = 0; // Force it to be zero terminated/
4204
4205 if (*buf == '#' || *buf == '\n')
4206 continue; // Skip comments / blank lines
4207 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4208 if ((p = (char *)strchr(buf, ':')))
4209 {
4210 in_addr_t src;
4211 *p = '\0';
4212 src = inet_addr(buf);
4213 if (src == INADDR_NONE)
4214 {
4215 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4216 exit(1);
4217 }
4218 // This entry is for a specific IP only
4219 if (src != config->bind_address)
4220 continue;
4221 *p = ':';
4222 pool = p+1;
4223 }
4224 if ((p = (char *)strchr(pool, '/')))
4225 {
4226 // It's a range
4227 int numbits = 0;
4228 in_addr_t start = 0, mask = 0;
4229
4230 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4231 *p++ = 0;
4232 if (!*p || !(numbits = atoi(p)))
4233 {
4234 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4235 continue;
4236 }
4237 start = ntohl(inet_addr(pool));
4238 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
4239
4240 // Add a static route for this pool
4241 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
4242 fmtaddr(htonl(start), 0), 32 + mask);
4243
4244 routeset(0, start, mask, 0, 1);
4245
4246 add_to_ip_pool(start, mask);
4247 }
4248 else
4249 {
4250 // It's a single ip address
4251 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4252 }
4253 }
4254 fclose(f);
4255 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4256 }
4257
4258 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4259 {
4260 struct sockaddr_in snoop_addr = {0};
4261 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4262 return;
4263
4264 snoop_addr.sin_family = AF_INET;
4265 snoop_addr.sin_addr.s_addr = destination;
4266 snoop_addr.sin_port = ntohs(port);
4267
4268 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
4269 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4270 htons(snoop_addr.sin_port));
4271
4272 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4273 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4274
4275 STAT(packets_snooped);
4276 }
4277
4278 static int dump_session(FILE **f, sessiont *s)
4279 {
4280 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4281 return 1;
4282
4283 if (!*f)
4284 {
4285 char filename[1024];
4286 char timestr[64];
4287 time_t now = time(NULL);
4288
4289 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4290 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4291
4292 if (!(*f = fopen(filename, "w")))
4293 {
4294 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4295 return 0;
4296 }
4297
4298 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4299 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4300 "# host: %s\n"
4301 "# endpoint: %s\n"
4302 "# time: %ld\n"
4303 "# uptime: %ld\n"
4304 "# format: username ip qos uptxoctets downrxoctets\n",
4305 hostname,
4306 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4307 now,
4308 now - basetime);
4309 }
4310
4311 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4312 fprintf(*f, "%s %s %d %u %u\n",
4313 s->user, // username
4314 fmtaddr(htonl(s->ip), 0), // ip
4315 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4316 (uint32_t) s->cin_delta, // uptxoctets
4317 (uint32_t) s->cout_delta); // downrxoctets
4318
4319 s->cin_delta = s->cout_delta = 0;
4320
4321 return 1;
4322 }
4323
4324 static void dump_acct_info(int all)
4325 {
4326 int i;
4327 FILE *f = NULL;
4328
4329
4330 CSTAT(dump_acct_info);
4331
4332 if (shut_acct_n)
4333 {
4334 for (i = 0; i < shut_acct_n; i++)
4335 dump_session(&f, &shut_acct[i]);
4336
4337 shut_acct_n = 0;
4338 }
4339
4340 if (all)
4341 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4342 dump_session(&f, &session[i]);
4343
4344 if (f)
4345 fclose(f);
4346 }
4347
4348 // Main program
4349 int main(int argc, char *argv[])
4350 {
4351 int i;
4352 int optdebug = 0;
4353 char *optconfig = CONFIGFILE;
4354
4355 time(&basetime); // start clock
4356
4357 // scan args
4358 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4359 {
4360 switch (i)
4361 {
4362 case 'd':
4363 if (fork()) exit(0);
4364 setsid();
4365 freopen("/dev/null", "r", stdin);
4366 freopen("/dev/null", "w", stdout);
4367 freopen("/dev/null", "w", stderr);
4368 break;
4369 case 'v':
4370 optdebug++;
4371 break;
4372 case 'c':
4373 optconfig = optarg;
4374 break;
4375 case 'h':
4376 snprintf(hostname, sizeof(hostname), "%s", optarg);
4377 break;
4378 default:
4379 printf("Args are:\n"
4380 "\t-d\t\tDetach from terminal\n"
4381 "\t-c <file>\tConfig file\n"
4382 "\t-h <hostname>\tForce hostname\n"
4383 "\t-v\t\tDebug\n");
4384
4385 return (0);
4386 break;
4387 }
4388 }
4389
4390 // Start the timer routine off
4391 time(&time_now);
4392 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4393
4394 initplugins();
4395 initdata(optdebug, optconfig);
4396
4397 init_cli(hostname);
4398 read_config_file();
4399 update_config();
4400 init_tbf(config->num_tbfs);
4401
4402 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4403 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4404 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4405 {
4406 struct rlimit rlim;
4407 rlim.rlim_cur = RLIM_INFINITY;
4408 rlim.rlim_max = RLIM_INFINITY;
4409 // Remove the maximum core size
4410 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4411 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4412
4413 // Make core dumps go to /tmp
4414 chdir("/tmp");
4415 }
4416
4417 if (config->scheduler_fifo)
4418 {
4419 int ret;
4420 struct sched_param params = {0};
4421 params.sched_priority = 1;
4422
4423 if (get_nprocs() < 2)
4424 {
4425 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4426 config->scheduler_fifo = 0;
4427 }
4428 else
4429 {
4430 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4431 {
4432 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4433 }
4434 else
4435 {
4436 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4437 config->scheduler_fifo = 0;
4438 }
4439 }
4440 }
4441
4442 /* Set up the cluster communications port. */
4443 if (cluster_init() < 0)
4444 exit(1);
4445
4446 inittun();
4447 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4448
4449 initudp();
4450 initrad();
4451 initippool();
4452
4453 // seed prng
4454 {
4455 unsigned seed = time_now ^ getpid();
4456 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4457 srand(seed);
4458 }
4459
4460 signal(SIGHUP, sighup_handler);
4461 signal(SIGCHLD, sigchild_handler);
4462 signal(SIGTERM, shutdown_handler);
4463 signal(SIGINT, shutdown_handler);
4464 signal(SIGQUIT, shutdown_handler);
4465
4466 // Prevent us from getting paged out
4467 if (config->lock_pages)
4468 {
4469 if (!mlockall(MCL_CURRENT))
4470 LOG(1, 0, 0, "Locking pages into memory\n");
4471 else
4472 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4473 }
4474
4475 // Drop privileges here
4476 if (config->target_uid > 0 && geteuid() == 0)
4477 setuid(config->target_uid);
4478
4479 mainloop();
4480
4481 /* remove plugins (so cleanup code gets run) */
4482 plugins_done();
4483
4484 // Remove the PID file if we wrote it
4485 if (config->wrote_pid && *config->pid_file == '/')
4486 unlink(config->pid_file);
4487
4488 /* kill CLI children */
4489 signal(SIGTERM, SIG_IGN);
4490 kill(0, SIGTERM);
4491 return 0;
4492 }
4493
4494 static void sighup_handler(int sig)
4495 {
4496 main_reload++;
4497 }
4498
4499 static void shutdown_handler(int sig)
4500 {
4501 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4502 }
4503
4504 static void sigchild_handler(int sig)
4505 {
4506 while (waitpid(-1, NULL, WNOHANG) > 0)
4507 ;
4508 }
4509
4510 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4511 {
4512 MD5_CTX ctx;
4513 *challenge_response = NULL;
4514
4515 if (!*config->l2tp_secret)
4516 {
4517 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4518 return;
4519 }
4520
4521 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4522
4523 *challenge_response = calloc(17, 1);
4524
4525 MD5_Init(&ctx);
4526 MD5_Update(&ctx, &id, 1);
4527 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4528 MD5_Update(&ctx, challenge, challenge_length);
4529 MD5_Final(*challenge_response, &ctx);
4530
4531 return;
4532 }
4533
4534 static int facility_value(char *name)
4535 {
4536 int i;
4537 for (i = 0; facilitynames[i].c_name; i++)
4538 {
4539 if (strcmp(facilitynames[i].c_name, name) == 0)
4540 return facilitynames[i].c_val;
4541 }
4542 return 0;
4543 }
4544
4545 static void update_config()
4546 {
4547 int i;
4548 char *p;
4549 static int timeout = 0;
4550 static int interval = 0;
4551
4552 // Update logging
4553 closelog();
4554 syslog_log = 0;
4555 if (log_stream)
4556 {
4557 if (log_stream != stderr)
4558 fclose(log_stream);
4559
4560 log_stream = NULL;
4561 }
4562
4563 if (*config->log_filename)
4564 {
4565 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4566 {
4567 char *p = config->log_filename + 7;
4568 if (*p)
4569 {
4570 openlog("l2tpns", LOG_PID, facility_value(p));
4571 syslog_log = 1;
4572 }
4573 }
4574 else if (strchr(config->log_filename, '/') == config->log_filename)
4575 {
4576 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4577 {
4578 fseek(log_stream, 0, SEEK_END);
4579 setbuf(log_stream, NULL);
4580 }
4581 else
4582 {
4583 log_stream = stderr;
4584 setbuf(log_stream, NULL);
4585 }
4586 }
4587 }
4588 else
4589 {
4590 log_stream = stderr;
4591 setbuf(log_stream, NULL);
4592 }
4593
4594 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4595 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4596
4597 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4598 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4599 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4600
4601 // reset MRU/MSS globals
4602 MRU = config->l2tp_mtu - L2TP_HDRS;
4603 if (MRU > PPPoE_MRU)
4604 MRU = PPPoE_MRU;
4605
4606 MSS = MRU - TCP_HDRS;
4607
4608 // Update radius
4609 config->numradiusservers = 0;
4610 for (i = 0; i < MAXRADSERVER; i++)
4611 if (config->radiusserver[i])
4612 {
4613 config->numradiusservers++;
4614 // Set radius port: if not set, take the port from the
4615 // first radius server. For the first radius server,
4616 // take the #defined default value from l2tpns.h
4617
4618 // test twice, In case someone works with
4619 // a secondary radius server without defining
4620 // a primary one, this will work even then.
4621 if (i > 0 && !config->radiusport[i])
4622 config->radiusport[i] = config->radiusport[i-1];
4623 if (!config->radiusport[i])
4624 config->radiusport[i] = RADPORT;
4625 }
4626
4627 if (!config->numradiusservers)
4628 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4629
4630 // parse radius_authtypes_s
4631 config->radius_authtypes = config->radius_authprefer = 0;
4632 p = config->radius_authtypes_s;
4633 while (p && *p)
4634 {
4635 char *s = strpbrk(p, " \t,");
4636 int type = 0;
4637
4638 if (s)
4639 {
4640 *s++ = 0;
4641 while (*s == ' ' || *s == '\t')
4642 s++;
4643
4644 if (!*s)
4645 s = 0;
4646 }
4647
4648 if (!strncasecmp("chap", p, strlen(p)))
4649 type = AUTHCHAP;
4650 else if (!strncasecmp("pap", p, strlen(p)))
4651 type = AUTHPAP;
4652 else
4653 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4654
4655 config->radius_authtypes |= type;
4656 if (!config->radius_authprefer)
4657 config->radius_authprefer = type;
4658
4659 p = s;
4660 }
4661
4662 if (!config->radius_authtypes)
4663 {
4664 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4665 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4666 }
4667
4668 // normalise radius_authtypes_s
4669 if (config->radius_authprefer == AUTHPAP)
4670 {
4671 strcpy(config->radius_authtypes_s, "pap");
4672 if (config->radius_authtypes & AUTHCHAP)
4673 strcat(config->radius_authtypes_s, ", chap");
4674 }
4675 else
4676 {
4677 strcpy(config->radius_authtypes_s, "chap");
4678 if (config->radius_authtypes & AUTHPAP)
4679 strcat(config->radius_authtypes_s, ", pap");
4680 }
4681
4682 if (!config->radius_dae_port)
4683 config->radius_dae_port = DAEPORT;
4684
4685 // re-initialise the random number source
4686 initrandom(config->random_device);
4687
4688 // Update plugins
4689 for (i = 0; i < MAXPLUGINS; i++)
4690 {
4691 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4692 continue;
4693
4694 if (*config->plugins[i])
4695 {
4696 // Plugin added
4697 add_plugin(config->plugins[i]);
4698 }
4699 else if (*config->old_plugins[i])
4700 {
4701 // Plugin removed
4702 remove_plugin(config->old_plugins[i]);
4703 }
4704 }
4705
4706 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4707 if (!config->multi_read_count) config->multi_read_count = 10;
4708 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4709 if (!*config->cluster_interface)
4710 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4711
4712 if (!config->cluster_hb_interval)
4713 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4714
4715 if (!config->cluster_hb_timeout)
4716 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4717
4718 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4719 {
4720 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4721 // late, ensure we're sufficiently larger than that
4722 int t = 4 * config->cluster_hb_interval + 11;
4723
4724 if (config->cluster_hb_timeout < t)
4725 {
4726 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4727 config->cluster_hb_timeout = t;
4728 }
4729
4730 // Push timing changes to the slaves immediately if we're the master
4731 if (config->cluster_iam_master)
4732 cluster_heartbeat();
4733
4734 interval = config->cluster_hb_interval;
4735 timeout = config->cluster_hb_timeout;
4736 }
4737
4738 // Write PID file
4739 if (*config->pid_file == '/' && !config->wrote_pid)
4740 {
4741 FILE *f;
4742 if ((f = fopen(config->pid_file, "w")))
4743 {
4744 fprintf(f, "%d\n", getpid());
4745 fclose(f);
4746 config->wrote_pid = 1;
4747 }
4748 else
4749 {
4750 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4751 }
4752 }
4753 }
4754
4755 static void read_config_file()
4756 {
4757 FILE *f;
4758
4759 if (!config->config_file) return;
4760 if (!(f = fopen(config->config_file, "r")))
4761 {
4762 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4763 return;
4764 }
4765
4766 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4767 cli_do_file(f);
4768 LOG(3, 0, 0, "Done reading config file\n");
4769 fclose(f);
4770 }
4771
4772 int sessionsetup(sessionidt s, tunnelidt t)
4773 {
4774 // A session now exists, set it up
4775 in_addr_t ip;
4776 char *user;
4777 sessionidt i;
4778 int r;
4779
4780 CSTAT(sessionsetup);
4781
4782 LOG(3, s, t, "Doing session setup for session\n");
4783
4784 if (!session[s].ip)
4785 {
4786 assign_ip_address(s);
4787 if (!session[s].ip)
4788 {
4789 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4790 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
4791 return 0;
4792 }
4793 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4794 fmtaddr(htonl(session[s].ip), 0));
4795 }
4796
4797
4798 // Make sure this is right
4799 session[s].tunnel = t;
4800
4801 // Join a bundle if the MRRU option is accepted
4802 if (session[s].mrru > 0 && !session[s].bundle)
4803 {
4804 LOG(3, s, t, "This session can be part of multilink bundle\n");
4805 if (join_bundle(s))
4806 cluster_send_bundle(session[s].bundle);
4807 }
4808
4809 // zap old sessions with same IP and/or username
4810 // Don't kill gardened sessions - doing so leads to a DoS
4811 // from someone who doesn't need to know the password
4812 {
4813 ip = session[s].ip;
4814 user = session[s].user;
4815 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4816 {
4817 if (i == s) continue;
4818 if (!session[s].opened) continue;
4819 if (ip == session[i].ip)
4820 {
4821 sessionkill(i, "Duplicate IP address");
4822 continue;
4823 }
4824
4825 if (config->allow_duplicate_users)
4826 continue;
4827
4828 if (session[s].walled_garden || session[i].walled_garden)
4829 continue;
4830
4831 // Allow duplicate sessions for guest account.
4832 if (*config->guest_user && !strcasecmp(user, config->guest_user))
4833 continue;
4834
4835 // Allow duplicate sessions for multilink ones of the same bundle.
4836 if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle)
4837 continue;
4838
4839 // Drop the new session in case of duplicate sessionss, not the old one.
4840 if (!strcasecmp(user, session[i].user))
4841 sessionkill(i, "Duplicate session for users");
4842 }
4843 }
4844
4845 {
4846 int routed = 0;
4847
4848 // Add the route for this session.
4849 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4850 {
4851 if ((session[s].ip & session[s].route[r].mask) ==
4852 (session[s].route[r].ip & session[s].route[r].mask))
4853 routed++;
4854
4855 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4856 }
4857
4858 // Static IPs need to be routed if not already
4859 // convered by a Framed-Route. Anything else is part
4860 // of the IP address pool and is already routed, it
4861 // just needs to be added to the IP cache.
4862 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4863 if (session[s].ip_pool_index == -1) // static ip
4864 {
4865 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4866 }
4867 else
4868 cache_ipmap(session[s].ip, s);
4869 }
4870
4871 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4872 lcp_open(s, t); // transition to Network phase and send initial IPCP
4873
4874 // Run the plugin's against this new session.
4875 {
4876 struct param_new_session data = { &tunnel[t], &session[s] };
4877 run_plugins(PLUGIN_NEW_SESSION, &data);
4878 }
4879
4880 // Allocate TBFs if throttled
4881 if (session[s].throttle_in || session[s].throttle_out)
4882 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4883
4884 session[s].last_packet = time_now;
4885
4886 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4887 fmtaddr(htonl(session[s].ip), 0),
4888 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4889
4890 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4891
4892 return 1; // RADIUS OK and IP allocated, done...
4893 }
4894
4895 //
4896 // This session just got dropped on us by the master or something.
4897 // Make sure our tables up up to date...
4898 //
4899 int load_session(sessionidt s, sessiont *new)
4900 {
4901 int i;
4902 int newip = 0;
4903
4904 // Sanity checks.
4905 if (new->ip_pool_index >= MAXIPPOOL ||
4906 new->tunnel >= MAXTUNNEL)
4907 {
4908 LOG(0, s, 0, "Strange session update received!\n");
4909 // FIXME! What to do here?
4910 return 0;
4911 }
4912
4913 //
4914 // Ok. All sanity checks passed. Now we're committed to
4915 // loading the new session.
4916 //
4917
4918 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4919
4920 // See if routes/ip cache need updating
4921 if (new->ip != session[s].ip)
4922 newip++;
4923
4924 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4925 if (new->route[i].ip != session[s].route[i].ip ||
4926 new->route[i].mask != session[s].route[i].mask)
4927 newip++;
4928
4929 // needs update
4930 if (newip)
4931 {
4932 int routed = 0;
4933
4934 // remove old routes...
4935 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4936 {
4937 if ((session[s].ip & session[s].route[i].mask) ==
4938 (session[s].route[i].ip & session[s].route[i].mask))
4939 routed++;
4940
4941 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4942 }
4943
4944 // ...ip
4945 if (session[s].ip)
4946 {
4947 if (session[s].ip_pool_index == -1) // static IP
4948 {
4949 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4950 }
4951 else // It's part of the IP pool, remove it manually.
4952 uncache_ipmap(session[s].ip);
4953 }
4954
4955 routed = 0;
4956
4957 // add new routes...
4958 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4959 {
4960 if ((new->ip & new->route[i].mask) ==
4961 (new->route[i].ip & new->route[i].mask))
4962 routed++;
4963
4964 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4965 }
4966
4967 // ...ip
4968 if (new->ip)
4969 {
4970 // If there's a new one, add it.
4971 if (new->ip_pool_index == -1)
4972 {
4973 if (!routed) routeset(s, new->ip, 0, 0, 1);
4974 }
4975 else
4976 cache_ipmap(new->ip, s);
4977 }
4978 }
4979
4980 // check v6 routing
4981 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4982 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4983
4984 // check filters
4985 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4986 {
4987 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4988 new->filter_in = 0;
4989 }
4990
4991 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4992 {
4993 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4994 new->filter_out = 0;
4995 }
4996
4997 if (new->filter_in != session[s].filter_in)
4998 {
4999 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
5000 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
5001 }
5002
5003 if (new->filter_out != session[s].filter_out)
5004 {
5005 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
5006 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
5007 }
5008
5009 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
5010 // for walking the sessions to forward byte counts to the master.
5011 config->cluster_highest_sessionid = s;
5012
5013 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
5014
5015 // Do fixups into address pool.
5016 if (new->ip_pool_index != -1)
5017 fix_address_pool(s);
5018
5019 return 1;
5020 }
5021
5022 static void initplugins()
5023 {
5024 int i;
5025
5026 loaded_plugins = ll_init();
5027 // Initialize the plugins to nothing
5028 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
5029 plugins[i] = ll_init();
5030 }
5031
5032 static void *open_plugin(char *plugin_name, int load)
5033 {
5034 char path[256] = "";
5035
5036 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
5037 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
5038 return dlopen(path, RTLD_NOW);
5039 }
5040
5041 // plugin callback to get a config value
5042 static void *getconfig(char *key, enum config_typet type)
5043 {
5044 int i;
5045
5046 for (i = 0; config_values[i].key; i++)
5047 {
5048 if (!strcmp(config_values[i].key, key))
5049 {
5050 if (config_values[i].type == type)
5051 return ((void *) config) + config_values[i].offset;
5052
5053 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
5054 key, type, config_values[i].type);
5055
5056 return 0;
5057 }
5058 }
5059
5060 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
5061 return 0;
5062 }
5063
5064 static int add_plugin(char *plugin_name)
5065 {
5066 static struct pluginfuncs funcs = {
5067 _log,
5068 _log_hex,
5069 fmtaddr,
5070 sessionbyuser,
5071 sessiontbysessionidt,
5072 sessionidtbysessiont,
5073 radiusnew,
5074 radiussend,
5075 getconfig,
5076 sessionshutdown,
5077 sessionkill,
5078 throttle_session,
5079 cluster_send_session,
5080 };
5081
5082 void *p = open_plugin(plugin_name, 1);
5083 int (*initfunc)(struct pluginfuncs *);
5084 int i;
5085
5086 if (!p)
5087 {
5088 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
5089 return -1;
5090 }
5091
5092 if (ll_contains(loaded_plugins, p))
5093 {
5094 dlclose(p);
5095 return 0; // already loaded
5096 }
5097
5098 {
5099 int *v = dlsym(p, "plugin_api_version");
5100 if (!v || *v != PLUGIN_API_VERSION)
5101 {
5102 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
5103 dlclose(p);
5104 return -1;
5105 }
5106 }
5107
5108 if ((initfunc = dlsym(p, "plugin_init")))
5109 {
5110 if (!initfunc(&funcs))
5111 {
5112 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
5113 dlclose(p);
5114 return -1;
5115 }
5116 }
5117
5118 ll_push(loaded_plugins, p);
5119
5120 for (i = 0; i < max_plugin_functions; i++)
5121 {
5122 void *x;
5123 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5124 {
5125 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
5126 ll_push(plugins[i], x);
5127 }
5128 }
5129
5130 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
5131 return 1;
5132 }
5133
5134 static void run_plugin_done(void *plugin)
5135 {
5136 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
5137
5138 if (donefunc)
5139 donefunc();
5140 }
5141
5142 static int remove_plugin(char *plugin_name)
5143 {
5144 void *p = open_plugin(plugin_name, 0);
5145 int loaded = 0;
5146
5147 if (!p)
5148 return -1;
5149
5150 if (ll_contains(loaded_plugins, p))
5151 {
5152 int i;
5153 for (i = 0; i < max_plugin_functions; i++)
5154 {
5155 void *x;
5156 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5157 ll_delete(plugins[i], x);
5158 }
5159
5160 ll_delete(loaded_plugins, p);
5161 run_plugin_done(p);
5162 loaded = 1;
5163 }
5164
5165 dlclose(p);
5166 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
5167 return loaded;
5168 }
5169
5170 int run_plugins(int plugin_type, void *data)
5171 {
5172 int (*func)(void *data);
5173
5174 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
5175 return PLUGIN_RET_ERROR;
5176
5177 ll_reset(plugins[plugin_type]);
5178 while ((func = ll_next(plugins[plugin_type])))
5179 {
5180 int r = func(data);
5181
5182 if (r != PLUGIN_RET_OK)
5183 return r; // stop here
5184 }
5185
5186 return PLUGIN_RET_OK;
5187 }
5188
5189 static void plugins_done()
5190 {
5191 void *p;
5192
5193 ll_reset(loaded_plugins);
5194 while ((p = ll_next(loaded_plugins)))
5195 run_plugin_done(p);
5196 }
5197
5198 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
5199 {
5200 struct nsctl request;
5201 struct nsctl response;
5202 int type = unpack_control(&request, buf, len);
5203 int r;
5204 void *p;
5205
5206 if (log_stream && config->debug >= 4)
5207 {
5208 if (type < 0)
5209 {
5210 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
5211 fmtaddr(addr->sin_addr.s_addr, 0), type);
5212 }
5213 else
5214 {
5215 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5216 dump_control(&request, log_stream);
5217 }
5218 }
5219
5220 switch (type)
5221 {
5222 case NSCTL_REQ_LOAD:
5223 if (request.argc != 1)
5224 {
5225 response.type = NSCTL_RES_ERR;
5226 response.argc = 1;
5227 response.argv[0] = "name of plugin required";
5228 }
5229 else if ((r = add_plugin(request.argv[0])) < 1)
5230 {
5231 response.type = NSCTL_RES_ERR;
5232 response.argc = 1;
5233 response.argv[0] = !r
5234 ? "plugin already loaded"
5235 : "error loading plugin";
5236 }
5237 else
5238 {
5239 response.type = NSCTL_RES_OK;
5240 response.argc = 0;
5241 }
5242
5243 break;
5244
5245 case NSCTL_REQ_UNLOAD:
5246 if (request.argc != 1)
5247 {
5248 response.type = NSCTL_RES_ERR;
5249 response.argc = 1;
5250 response.argv[0] = "name of plugin required";
5251 }
5252 else if ((r = remove_plugin(request.argv[0])) < 1)
5253 {
5254 response.type = NSCTL_RES_ERR;
5255 response.argc = 1;
5256 response.argv[0] = !r
5257 ? "plugin not loaded"
5258 : "plugin not found";
5259 }
5260 else
5261 {
5262 response.type = NSCTL_RES_OK;
5263 response.argc = 0;
5264 }
5265
5266 break;
5267
5268 case NSCTL_REQ_HELP:
5269 response.type = NSCTL_RES_OK;
5270 response.argc = 0;
5271
5272 ll_reset(loaded_plugins);
5273 while ((p = ll_next(loaded_plugins)))
5274 {
5275 char **help = dlsym(p, "plugin_control_help");
5276 while (response.argc < 0xff && help && *help)
5277 response.argv[response.argc++] = *help++;
5278 }
5279
5280 break;
5281
5282 case NSCTL_REQ_CONTROL:
5283 {
5284 struct param_control param = {
5285 config->cluster_iam_master,
5286 request.argc,
5287 request.argv,
5288 0,
5289 NULL,
5290 };
5291
5292 int r = run_plugins(PLUGIN_CONTROL, &param);
5293
5294 if (r == PLUGIN_RET_ERROR)
5295 {
5296 response.type = NSCTL_RES_ERR;
5297 response.argc = 1;
5298 response.argv[0] = param.additional
5299 ? param.additional
5300 : "error returned by plugin";
5301 }
5302 else if (r == PLUGIN_RET_NOTMASTER)
5303 {
5304 static char msg[] = "must be run on master: 000.000.000.000";
5305
5306 response.type = NSCTL_RES_ERR;
5307 response.argc = 1;
5308 if (config->cluster_master_address)
5309 {
5310 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5311 response.argv[0] = msg;
5312 }
5313 else
5314 {
5315 response.argv[0] = "must be run on master: none elected";
5316 }
5317 }
5318 else if (!(param.response & NSCTL_RESPONSE))
5319 {
5320 response.type = NSCTL_RES_ERR;
5321 response.argc = 1;
5322 response.argv[0] = param.response
5323 ? "unrecognised response value from plugin"
5324 : "unhandled action";
5325 }
5326 else
5327 {
5328 response.type = param.response;
5329 response.argc = 0;
5330 if (param.additional)
5331 {
5332 response.argc = 1;
5333 response.argv[0] = param.additional;
5334 }
5335 }
5336 }
5337
5338 break;
5339
5340 default:
5341 response.type = NSCTL_RES_ERR;
5342 response.argc = 1;
5343 response.argv[0] = "error unpacking control packet";
5344 }
5345
5346 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5347 if (!buf)
5348 {
5349 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5350 return;
5351 }
5352
5353 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5354 if (r > 0)
5355 {
5356 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5357 if (log_stream && config->debug >= 4)
5358 {
5359 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5360 dump_control(&response, log_stream);
5361 }
5362 }
5363 else
5364 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5365 fmtaddr(addr->sin_addr.s_addr, 0), r);
5366
5367 free(buf);
5368 }
5369
5370 static tunnelidt new_tunnel()
5371 {
5372 tunnelidt i;
5373 for (i = 1; i < MAXTUNNEL; i++)
5374 {
5375 if (tunnel[i].state == TUNNELFREE)
5376 {
5377 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5378 if (i > config->cluster_highest_tunnelid)
5379 config->cluster_highest_tunnelid = i;
5380 return i;
5381 }
5382 }
5383 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5384 return 0;
5385 }
5386
5387 //
5388 // We're becoming the master. Do any required setup..
5389 //
5390 // This is principally telling all the plugins that we're
5391 // now a master, and telling them about all the sessions
5392 // that are active too..
5393 //
5394 void become_master(void)
5395 {
5396 int s, i;
5397 static struct event_data d[RADIUS_FDS];
5398 struct epoll_event e;
5399
5400 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5401
5402 // running a bunch of iptables commands is slow and can cause
5403 // the master to drop tunnels on takeover--kludge around the
5404 // problem by forking for the moment (note: race)
5405 if (!fork_and_close())
5406 {
5407 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5408 {
5409 if (!session[s].opened) // Not an in-use session.
5410 continue;
5411
5412 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5413 }
5414 exit(0);
5415 }
5416
5417 // add radius fds
5418 e.events = EPOLLIN;
5419 for (i = 0; i < RADIUS_FDS; i++)
5420 {
5421 d[i].type = FD_TYPE_RADIUS;
5422 d[i].index = i;
5423 e.data.ptr = &d[i];
5424
5425 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5426 }
5427 }
5428
5429 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5430 {
5431 int s, i;
5432 int count = 0;
5433 int buckets[64];
5434
5435 if (CLI_HELP_REQUESTED)
5436 return CLI_HELP_NO_ARGS;
5437
5438 time(&time_now);
5439 for (i = 0; i < 64;++i) buckets[i] = 0;
5440
5441 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5442 {
5443 int idle;
5444 if (!session[s].opened)
5445 continue;
5446
5447 idle = time_now - session[s].last_packet;
5448 idle /= 5 ; // In multiples of 5 seconds.
5449 if (idle < 0)
5450 idle = 0;
5451 if (idle > 63)
5452 idle = 63;
5453
5454 ++count;
5455 ++buckets[idle];
5456 }
5457
5458 for (i = 0; i < 63; ++i)
5459 {
5460 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5461 }
5462 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5463 cli_print(cli, "%d total sessions open.", count);
5464 return CLI_OK;
5465 }
5466
5467 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5468 {
5469 int s, i;
5470 int count = 0;
5471 int buckets[64];
5472
5473 if (CLI_HELP_REQUESTED)
5474 return CLI_HELP_NO_ARGS;
5475
5476 time(&time_now);
5477 for (i = 0; i < 64;++i) buckets[i] = 0;
5478
5479 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5480 {
5481 int open = 0, d;
5482 if (!session[s].opened)
5483 continue;
5484
5485 d = time_now - session[s].opened;
5486 if (d < 0)
5487 d = 0;
5488 while (d > 1 && open < 32)
5489 {
5490 ++open;
5491 d >>= 1; // half.
5492 }
5493 ++count;
5494 ++buckets[open];
5495 }
5496
5497 s = 1;
5498 for (i = 0; i < 30; ++i)
5499 {
5500 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5501 s <<= 1;
5502 }
5503 cli_print(cli, "%d total sessions open.", count);
5504 return CLI_OK;
5505 }
5506
5507 /* Unhide an avp.
5508 *
5509 * This unencodes the AVP using the L2TP secret and the previously
5510 * stored random vector. It overwrites the hidden data with the
5511 * unhidden AVP subformat.
5512 */
5513 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5514 {
5515 MD5_CTX ctx;
5516 uint8_t digest[16];
5517 uint8_t *last;
5518 size_t d = 0;
5519 uint16_t m = htons(type);
5520
5521 // Compute initial pad
5522 MD5_Init(&ctx);
5523 MD5_Update(&ctx, (unsigned char *) &m, 2);
5524 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5525 MD5_Update(&ctx, vector, vec_len);
5526 MD5_Final(digest, &ctx);
5527
5528 // pointer to last decoded 16 octets
5529 last = value;
5530
5531 while (len > 0)
5532 {
5533 // calculate a new pad based on the last decoded block
5534 if (d >= sizeof(digest))
5535 {
5536 MD5_Init(&ctx);
5537 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5538 MD5_Update(&ctx, last, sizeof(digest));
5539 MD5_Final(digest, &ctx);
5540
5541 d = 0;
5542 last = value;
5543 }
5544
5545 *value++ ^= digest[d++];
5546 len--;
5547 }
5548 }
5549
5550 int find_filter(char const *name, size_t len)
5551 {
5552 int free = -1;
5553 int i;
5554
5555 for (i = 0; i < MAXFILTER; i++)
5556 {
5557 if (!*ip_filters[i].name)
5558 {
5559 if (free < 0)
5560 free = i;
5561
5562 continue;
5563 }
5564
5565 if (strlen(ip_filters[i].name) != len)
5566 continue;
5567
5568 if (!strncmp(ip_filters[i].name, name, len))
5569 return i;
5570 }
5571
5572 return free;
5573 }
5574
5575 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5576 {
5577 switch (p->op)
5578 {
5579 case FILTER_PORT_OP_EQ: return port == p->port;
5580 case FILTER_PORT_OP_NEQ: return port != p->port;
5581 case FILTER_PORT_OP_GT: return port > p->port;
5582 case FILTER_PORT_OP_LT: return port < p->port;
5583 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5584 }
5585
5586 return 0;
5587 }
5588
5589 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5590 {
5591 switch (op)
5592 {
5593 case FILTER_FLAG_OP_ANY:
5594 return (flags & sflags) || (~flags & cflags);
5595
5596 case FILTER_FLAG_OP_ALL:
5597 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5598
5599 case FILTER_FLAG_OP_EST:
5600 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5601 }
5602
5603 return 0;
5604 }
5605
5606 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5607 {
5608 uint16_t frag_offset;
5609 uint8_t proto;
5610 in_addr_t src_ip;
5611 in_addr_t dst_ip;
5612 uint16_t src_port = 0;
5613 uint16_t dst_port = 0;
5614 uint8_t flags = 0;
5615 ip_filter_rulet *rule;
5616
5617 if (len < 20) // up to end of destination address
5618 return 0;
5619
5620 if ((*buf >> 4) != 4) // IPv4
5621 return 0;
5622
5623 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5624 proto = buf[9];
5625 src_ip = *(in_addr_t *) (buf + 12);
5626 dst_ip = *(in_addr_t *) (buf + 16);
5627
5628 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5629 {
5630 int l = (buf[0] & 0xf) * 4; // length of IP header
5631 if (len < l + 4) // ports
5632 return 0;
5633
5634 src_port = ntohs(*(uint16_t *) (buf + l));
5635 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5636 if (proto == IPPROTO_TCP)
5637 {
5638 if (len < l + 14) // flags
5639 return 0;
5640
5641 flags = buf[l + 13] & 0x3f;
5642 }
5643 }
5644
5645 for (rule = ip_filters[filter].rules; rule->action; rule++)
5646 {
5647 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5648 continue;
5649
5650 if (rule->src_wild != INADDR_BROADCAST &&
5651 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5652 continue;
5653
5654 if (rule->dst_wild != INADDR_BROADCAST &&
5655 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5656 continue;
5657
5658 if (frag_offset)
5659 {
5660 // layer 4 deny rules are skipped
5661 if (rule->action == FILTER_ACTION_DENY &&
5662 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5663 continue;
5664 }
5665 else
5666 {
5667 if (rule->frag)
5668 continue;
5669
5670 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5671 {
5672 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5673 continue;
5674
5675 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5676 continue;
5677
5678 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5679 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5680 continue;
5681 }
5682 }
5683
5684 // matched
5685 rule->counter++;
5686 return rule->action == FILTER_ACTION_PERMIT;
5687 }
5688
5689 // default deny
5690 return 0;
5691 }